Proceedings Volume 10010

Advanced Topics in Optoelectronics, Microelectronics, and Nanotechnologies VIII

Marian Vladescu, Cornel T. Panait, Razvan Tamas, et al.
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Proceedings Volume 10010

Advanced Topics in Optoelectronics, Microelectronics, and Nanotechnologies VIII

Marian Vladescu, Cornel T. Panait, Razvan Tamas, et al.
Purchase the printed version of this volume at proceedings.com or access the digital version at SPIE Digital Library.

Volume Details

Date Published: 23 December 2016
Contents: 11 Sessions, 128 Papers, 0 Presentations
Conference: Advanced Topics in Optoelectronics, Microelectronics, and Nanotechnologies 2016 2016
Volume Number: 10010

Table of Contents

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Table of Contents

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  • Front Matter: Volume 10010
  • Plenary Session
  • Advanced Materials and New Technologies
  • Diffractive, Micro-Optics, and Optical Signal Processing
  • Sensors, Microsystems, and Instruments
  • Microphotonics and Micronanotechnologies
  • Modeling, Design, and Simulation
  • Optics-Inspired Approaches for Non-Optical Applications: Systems, Devices, and Signal Processing
  • Plasma Methods and Diagnostics Used for Surface Treatments
  • Medical Optoelectronics
  • Additional Paper
Front Matter: Volume 10010
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Front Matter: Volume 10010
This PDF file contains the front matter associated with SPIE Proceedings Volume 10010, including the Title Page, Copyright information, Table of Contents, Introduction, and Conference Committee listing.
Plenary Session
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Interferometric correlator for acoustic radiation and underlying structural vibration
Adela Apostol, James Kilpatrick, Vladimir Markov, et al.
In this paper we discuss the background and principles of an optical non-contact sensor fusion concept, the Interferometric Correlator for Acoustic Radiation and Underlying Structural Vibration (ICARUSV) and give practical example of its capabilities, focusing on its ability to simultaneously capture, visualize and quantitatively characterize full-field non-stationary structural dynamics and unsteady radiated sound fields or transient flow fields around the structure of interest. The ICARUSV’s multi-sensor design is based on a parallel architecture and therefore the data capture is fast and inherently support a wide variety of spatio-temporal or spatio-spectral analysis methods which characterize the structural or acoustic/flow field dynamics as it occurs in real time, including short-lived transient events. No other technology available today offers this level of multi-parameter multi-dimensional data1.
Plasma and particles
Petr Špatenka, Tat'ana Vacková, Vojtĕch Nováček, et al.
Plasma has been proved as a standard industrial method for surface treatment of solid bulk materials. Recently plasma has also been used in connection with production, treatment and functionalization of powder and granulate materials. Functionalization was originally developed for hydrophylization of hydrophobic surfaces of particles made from various materials.

An industrial scale device with a capacity of several hundreds of tons per year based on plasma treatment will be presented. As examples of the applications are given plasma treated polyethylene powder dispersed in the water; and very good adhesion of polymer powders to metals or glass, which is promising for development of new generation of thermoplastic composites.
Electromagnetic and acoustic bimodality for the detection and localization of electrical arc faults
C. Vasile, C. Ioana, A. Digulescu, et al.
Electrical arc faults pose an important problem to electrical installations worldwide, be it production facilities or distribution systems. In this context, it is easy to assess the economic repercussions of such a fault, when power supply is cut off downstream of its location, while also realizing that an early detection of the on-site smaller scale faults would be of great benefit. This articles serves as a review of the current state-of-the-art work that has been carried out on the subject of detection and localization of electrical arc faults, by exploiting the bimodality of this phenomenon, which generates simultaneously electromagnetic and acoustic waves, propagating in a free space path. En experimental setup has been defined, to demonstrate principles stated in previous works by the authors, and signal processing methods have been used in order to determine the DTOA (difference-of-time-of-arrival) of the acoustic signals, which allows localization of the transient fault. In the end there is a discussion regarding the results and further works, which aims to validate this approach in more real-life applications.
The use of 2D Hilbert transform for phase retrieval of speckle fields
The use of a “window” 2D Hilbert transform for reconstruction of the phase distribution of remote objects is proposed. It is shown that the advantage of this approach consists in the invariance of a phase map to a change of the position of the kernel of transformation and in a possibility to reconstruct the structure-forming elements of the skeleton of an optical field, including singular points and saddle points. We demonstrate the possibility to reconstruct the equi-phase lines within a narrow confidence interval, and introduce a new algorithm for solving the phase problem for random 2D intensity distributions.
On-wafer high temperature characterization system
L. Teodorescu, F. Drăghici, I. Rusu, et al.
In this work a on-wafer high temperature characterization system for wide bandgap semiconductor devices and circuits has been designed, implemented and tested. The proposed system can perform the wafer temperature adjustment in a large domain, from the room temperature up to 3000C with a resolution better than ±0.50C. In order to obtain both low-noise measurements and low EMI, the heating element of the wafer chuck is supplied in two ways: one is from a DC linear power supply connected to the mains electricity, another one is from a second DC unit powered by batteries. An original temperature control algorithm, different from classical PID, is used to modify the power applied to the chuck.
Study regarding the spline interpolation accuracy of the experimentally acquired data
Emil M. Oanta, Alin Danisor, Razvan Tamas
Experimental data processing is an issue that must be solved in almost all the domains of science. In engineering we usually have a large amount of data and we try to extract the useful signal which is relevant for the phenomenon under investigation. The criteria used to consider some points more relevant then some others may take into consideration various conditions which may be either phenomenon dependent, or general. The paper presents some of the ideas and tests regarding the identification of the best set of criteria used to filter the initial set of points in order to extract a subset which best fits the approximated function. If the function has regions where it is either constant, or it has a slow variation, fewer discretization points may be used. This means to create a simpler solution to process the experimental data, keeping the accuracy in some fair good limits.
Enhanced automated platform for 2D characterization of RFID communications
The characterization of the quality of communication between an RFID reader and a transponder at all expected positions of the latter on the reader antenna is of primal importance for the evaluation of performance of an RFID system. Continuing the line of instruments developed for this purpose by the authors, the present work proposes an enhanced version of a previously introduced automated platform for 2D evaluation. By featuring higher performance in terms of mechanical speed, the new version allows to obtain 2D maps of communication with a higher resolution that would have been prohibitive in terms of test duration with the previous version. The list of measurement procedures that can be executed with the platform is now enlarged with additional ones, such as the determination of the variation of the magnetic coupling between transponder and antenna across the antenna surface and the utilization of transponder simulators for evaluation of the quality of communication.
Advanced Materials and New Technologies
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Synthesis and photophysics of conjugated azomethine polyrotaxanes
The photophysical properties of two polyazomethine polyrotaxanes (4•αCD and 4•TMS-αCD) composed of pyrene and triazole encapsulated into native and permodified α-cyclodextrin (αCD and TMS-αCD) cavities have been investigated and compared with those of the non-rotaxane 4 counterparts. Rotaxane formation results in improvements of the solubility in organic solvents, as well as better film forming ability combined with a high transparency. The polyrotaxane 4•TMS-αCD was soluble in toluene/DMF1/1 v/v mixture and displayed useful levels of thermal stability. The fluorescence spectroscopy of 4•αCD and 4•TMS-αCD shows an obvious blue shift both in excitation and emission spectra with respect to those of non-rotaxane counterparts. 4•TMS-αCD displays a continuous absorption spectrum, whereas the reference 4 does not show any absorption maximum, neither for its emission maximum, presumably because of its very low solubility in DMF. The improved fluorescence efficiency (ΦPL) of both polyrotaxanes is attributed to the hydrophobic micro-environment within αCD and TMS-αCD cavities. The surfaces of non-rotaxane 4 counterparts showed globular formations with an agglomeration tendency, while the encapsulated 4•αCD and 4•TMS-αCD rotaxane compounds exhibited smoother surfaces, comprised by smaller grains uniformly distributed on the surface of the solid films. The presence of the αCD and TMS-αCD in 4·αCD and 4•TMS-αCD polyrotaxanes affects the LUMO energy levels to a greater extent than its HOMO energy with respect to reference 4. The wetting properties of spin-coated film of 4•TMS-αCD in water (polar) and diiodomethane (apolar), indicates that TMS-αCD makes its surface more hydrophobic. The dispersive and polar components are lower than that of the reference compounds. The doping of the rotaxane structures with iodine (I2) indicated smaller improvements of electrical conductivity (σ) values, which presents a tradeoff with their better solubility, process ability, surface characteristics and ΦPL.
Metal nanoparticles (other than gold or silver) prepared using plant extracts for medical applications
Roxana-Diana Pasca, Szabolcs Santa, Levente Zsolt Racz, et al.
There are many modalities to prepare metal nanoparticles, but the reducing of the metal ions with plant extracts is one of the most promising because it is considerate less toxic for the environment, suitable for the use of those nanoparticles in vivo and not very expensive. Various metal ions have been already studied such as: cobalt, copper, iron, platinum, palladium, zinc, indium, manganese and mercury and the number of plant extracts used is continuously increasing. The prepared systems were characterized afterwards with a great number of methods of investigation: both spectroscopic (especially UV-Vis spectroscopy) and microscopic (in principal, electron microscopy-TEM) methods. The applications of the metal nanoparticles obtained are diverse and not completely known, but the medical applications of such nanoparticles occupy a central place, due to their nontoxic components, but some diverse industrial applications do not have to be forgotten.
Ion-beam synthesis of zinc-based nanoparticles in SiO2
Karolina Czarnacka, Maksim A. Makhavikou, Fadei F. Komarov
In this paper production process of Zn nanocrystals in SiO2 by using an implantation of high dose zinc ions with energy of 130 keV and annealing process in 700°C were described. Using electron microscopy was established that annealing causes extension of admixtures distribution on depth and zinc nanoparticles size increasing from approx. 1 - 6 nm to 12 - 18 nm.

For prepared material AC conductivity measurements were made in temperatures range from liquid nitride temperature (LNT) to 373 K and at frequencies range from 50 Hz to 5 MHz. Strong frequency dependence on conductivity proves that in this nanocomposite Zn-SiO2 conduction takes place by electron hopping exchange (tunneling) between metallic phase nanoparticles.

It was established that three activation energies of conductivity occurs in temperatures range of LNT – 373 K – in low temperatures ΔE1≈0.001 eV, in medium temperatures ΔE2≈0.025 eV and in higher temperatures area ΔE3≈0.096 eV. This is due to the presence of at least two types of nanoparticles. First there are zinc nanoparticles with zinc oxide coating, second there are nanoparticles without the coating. The highest activation energy occurs during electrons tunneling between nanoparticles with zinc oxide coating. Intermediate activation energy corresponds to tunneling from nanoparticle with coating to nanoparticle without coating or conversely. The lowest activation energy corresponds to electrons hopping between nanoparticles without coatings.
AC electric properties of nanocomposite (FeCoZr)0.818(CaF2)0.182 annealed in the tubular furnace
In this paper the influence of 15-minutes annealing in temperature range 398 K – 723 K with step 25 K on the frequency dependence on conductivity of nanocomposite (FeCoZr)x(CaF2)(100-x) was exanimate. Nanocomposite with metallic phase content x = 81.8 at.% was produced by ion-beam sputtering in mixed argon and oxygen atmosphere. Measurement were made in frequency range 50 Hz – 5 MHz and temperatures from 15 K to 375 K.

It was found that to annealing temperature 523 K in measurement temperatures a less than room temperature a weak dependence of dielectric type of conductivity occurs in materials – the conductivity increases with temperature increase. At temperatures above room temperature a phase transition dielectric-metal is observed and a conductivity decreases with temperature increase. Growth stage of conductivity was observed in the frequency range above 105 Hz. The relaxation time for this stage is of the order 10-6 s. Annealing in the temperature above 523 K led to the appearance of additional low temperature stage of conductivity, for which the relaxation time is of the order of 10-4 s. The appearance of the low-frequency stage of conductivity increase is associated with oxidation of surface of nanoparticles of metallic phase during annealing, the growing barrier of potential and relaxation time. Further increase of annealing temperature above 673 K causes a further increase of the width of the barrier, and activation energy becomes so much that relaxation times for low-frequency stage grown above 10-2 s. Therefore, low-frequency stage is moves further into the area of low frequency and it becomes unnoticeable because it go beyond the lower range (50 Hz) of used meter.
Features of the formation of structure and properties of transition metals boridonitrides composite films
Alexander A. Goncharov, Andrey N. Yunda, Tomasz N. Kołtunowicz
Researches of formation features of nanostructured film condensates deposited by reactive magnetron (HF and DC) sputtering of transition metals diborides targets was analyzed. Amorphous-crystalline composite film (MeB2 + BN), consisting of grains of nanocrystalline phase MeB2 and amorphous graphite-like phase BN filling intergranular space, is formed at reactive sputtering in (Ar + N2) mixture. Investigations of composition and physico-mechanical properties of transition metals boridenitrides composite films were carried out. The amount of phase МеВ2 decreases, and phase BN enlarges with an increase in percentage content of nitrogen in a mixture, that leads to hardness and elastic modulus reduction respectively and to elasticity increase of boridonitrides thin films compared with diborides films. It is shown that viscoelasticity of Me–B–N thin films is caused by the presence of amorphous boron nitride phase.
Structural analysis of multilayer metal nitride films CrN/MoN using electron backscatter diffraction (EBSD)
Bogdan Postolnyi, Oleksandr Bondar, Marek Opielak, et al.
The electron backscatter diffraction (EBSD) analysis method was used for studying structure and properties of multilayer nitride CrN/MoN coatings fabricated by cathode arc physical vapour deposition (Arc-PVD). Samples were deposited on steel substrate with different single layer thickness from tens nanometers to 1 micron and with total thickness of coatings up to 8-13 μm. Colour grains mapping, grain size distribution profiles, pole figures and texture analyses were the main research instruments. Studying of obtained coatings was performed on specially prepared polished cross-section samples. The dependence between single layer thickness and grain size of materials, which is also changing through depth profile of the coating, was observed. In addition, it was possible to study phase composition, prevailing crystals orientation, dominant texture and grains growth. Studying of grains size, as well as other indicated parameters, is a very important task because it gives an information about grains interfaces volume, which causes changes in mechanical properties of material. Obtained results were cross-checked by X-ray diffraction analysis (XRD) where it was possible.
Structural features of the multilayer nitride coatings formation
Yaroslav O. Kravchenko, Alexander A. Goncharov, Andrey N. Yunda, et al.
The features of structure and properties formation of multicomponent (high-entropy) and multilayer transition metals nitride coatings of deposited by reactive magnetron (HF and DC) sputtering of targets in Ar + N2 mixture atmosphere was analyzed. It is shown that the formation of texture and columnar structure of films occurs due to changes the deposition conditions. Moreover, transition metals nitride films (TiN, HfN, et al.) have textured growth plane (111) and nanohardness values about 36 GPa at close to stoichiometric compositions. X-ray analysis of nitride multilayer coatings shows that the multilayers have a cubic structure with a preferential orientation (111) or (200) depending on the period of modulation Λ. It is shown that one of the methods of its preparation is the use of elements (Zr,Y). Correlations between structure and physico-mechanical properties of the coatings, as well as the effect of multilayers deposition conditions and modulation period on the hardness value were exhibited. Conducted researches show that the use of multi-component and multi-layered nitride coating allows to obtain super hard nitride coating (> 40 GPa,) with high elastic recovery (We up to 83%) and high resistance to plastic deformation (H3/E*2 up to 0.75).
Synthesis and characterization of novel main chain bisazobenzene polyphosphonates
Tăchiţă Vlad-Bubulac, Diana Serbezeanu, Ionela-Daniela Carja
Preparation and experimental studies on the phase transition and morphology of novel phosphorus-containing copolymers, having bisazobenzene units and variable molar ratio of aliphatic segments in the main chain, were performed. The chemical structure of the novel compounds has been confirmed by Fourier transform infrared and 1H-NMR spectroscopy. The thermal stability was investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) while the mesomorphic behavior was closely observed with polarized light microscope (PLM) and by X-ray diffraction measurements, structure-properties relationships being established and discussed.
New complexes of silver (I) with N-hydroxy-succinimide
Doina Sibiescu, Carmen Mîţă, Mihaela Vizitiu, et al.
Over the last period of time silver was considerably studied due to its lower resistivity. In the field of materials science, silver was used in applications such as: microelectronics components of high – temperature superconductiviting materials, bactericidal coatings and others domains. This study presents the process of obtaining and characterization the new complexes of silver (I) with Nhydroxy- succinimide. In the process of obtaining the new complex compounds in aqous solution, first we have to look at conductometry and UV-Vis absorbtion spectroscopy in order to determine the molar ratio silver : N-hydroxysuccinimide and the stability constants. The obtained solid coordination compounds were characterized by elemental analysis, IR spectroscopy and also was investigated of their thermostability. The X-ray powder diffraction reflects that the complexes compounds of silver (I) with N-hydroxysuccinimide are amorphous. In our further studies we want to determine if the new synthetized compounds will present the same or improuved properties as in the above mentioned silver characteristics.
Low energy switching driver for printed electrochromic displays
Ciprian Ionescu, Robert Alexandru Dobre
This paper continues our investigations in relatively new developed printed electrochromic displays (ECDs). There are some advantages of ECDs that recommend them for specific low end and short time disposable display applications, for instance the ECD devices present low power consumption (they are non-emissive, reflective, i.e. passive) and have a good viewing angle, looking like ink on paper. It is to note that these displays are still in research, and partly present on the market. There are a lot of papers regarding the chemistry and electro-chemistry of the device, but very few about concrete schematics for driving these displays. Due to their low penetration in applications, and due to lack of standardization, there are not yet realized custom drivers in form of integrated circuits. The driving of these circuits is not at all so simple. These are very sensitive devices in what it concerns exceeding the drive pulse duration and voltage level. In order to take full advantage of the low power consumption of this device, a good driver circuitry needs to be realized also in the “low power” class. We propose in this paper an original driving circuit, that has very low consumption and that can be even supplied by a supercapacitor or by a printed battery. The whole structure can be further integrated as a system on foil.
Comparative shear tests of some low temperature lead-free solder pastes
Mihai Branzei, Ioan Plotog, Gaudentiu Varzaru, et al.
The range of electronic components and as a consequence, all parts of automotive electronic equipment operating temperatures in a vehicle is given by the location of that equipment, so the maximum temperature can vary between 358K and 478K1. The solder joints could be defined as passive parts of the interconnection structure of automotive electronic equipment, at a different level, from boards of electronic modules to systems. The manufacturing costs reduction necessity and the RoHS EU Directive3, 7 consequences generate the trend to create new Low-Temperature Lead-Free (LTLF) solder pastes family9. In the paper, the mechanical strength of solder joints and samples having the same transversal section as resistor 1206 case type made using the same LTLF alloys into Vapour Phase Soldering (VPS) process characterized by different cooling rates (slow and rapid) and two types of test PCBs pads finish, were benchmarked at room temperature. The presented work extends the theoretical studies and experiments upon heat transfer in VPSP in order to optimize the technology for soldering process (SP) of automotive electronic modules and could be extended for home and modern agriculture appliances industry. The shear forces (SF) values of the LTLF alloy samples having the same transversal section as resistor 1206 case type will be considered as references values of a database useful in the new solder alloy creation processes and their qualification for automotive electronics domain.
Diffractive, Micro-Optics, and Optical Signal Processing
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Cooperative entangled effects between the cavity mode components of Raman process
The cooperative excitation and absorption of light into three cavity modes (pump, Stokes and anti-Stokes), stimulated by excited radiators, is studied as bound entangled states of the photon subsystem. The three modes collective Roman emission and its connection with entangled state is defined introducing the cooperative description between photons of cavity modes. In the case, when the scattering rates in the Stokes and anti-Stokes modes coincide, the SU(2) and SU(1,1) symmetries are applied for a simple description of these cooperative processes. The possibilities to realize this effect in the free space is proposed, replacing the cavity modes with dipole active excited atoms in tow-quantum interaction with dipole-forbidden transitions of D atom. The statistical properties and detection method are proposed using the information entropy and atomic correlation functions.
Methods and means of Fourier-Stokes polarimetry and the spatial frequency filtering of phase anisotropy manifestations
O. Yu. Novakovskaya, A. G. Ushenko, A. V. Dubolazov, et al.
The theoretical background of azimuthally stable method of Jones-matrix mapping of histological sections of biopsy of myocardium tissue on the basis of spatial frequency selection of the mechanisms of linear and circular birefringence is presented. The diagnostic application of a new correlation parameter – complex degree of mutual anisotropy – is analytically substantiated. The method of measuring coordinate distributions of complex degree of mutual anisotropy with further spatial filtration of their high- and low-frequency components is developed. The interconnections of such distributions with parameters of linear and circular birefringence of myocardium tissue histological sections are found. The comparative results of measuring the coordinate distributions of complex degree of mutual anisotropy formed by fibrillar networks of myosin fibrils of myocardium tissue of different necrotic states – dead due to coronary heart disease and acute coronary insufficiency are shown. The values and ranges of change of the statistical (moments of the 1st – 4th order) parameters of complex degree of mutual anisotropy coordinate distributions are studied. The objective criteria of differentiation of cause of death are determined.
Methods and means of Stokes-polarimetry microscopy of optically anisotropic biological layers
The results of optical modeling of biological tissues polycrystalline multilayer networks have been presented. Algorithms of reconstruction of parameter distributions were determined that describe the linear and circular birefringence. For the separation of the manifestations of these mechanisms we propose a method of space-frequency filtering. Criteria for differentiation of benign and malignant tissues of the women reproductive sphere were found.
Methods and means of Fourier-Stokes polarimetry and the spatial-frequency filtering of phase anisotropy manifestations in endometriosis diagnostics
This research presents investigation results of diagnostic efficiency of a new azimuthally stable Mueller-matrix method of laser autofluorescence coordinate distributions analysis of dried polycrystalline films of uterine cavity peritoneal fluid. A new model of generalized optical anisotropy of biological tissues protein networks is proposed in order to define the processes of laser autofluorescence. The influence of complex mechanisms of both phase anisotropy (linear birefringence and optical activity) and linear (circular) dichroism is taken into account. The interconnections between the azimuthally stable Mueller-matrix elements characterizing laser autofluorescence and different mechanisms of optical anisotropy are determined. The statistic analysis of coordinate distributions of such Mueller-matrix rotation invariants is proposed. Thereupon the quantitative criteria (statistic moments of the 1st to the 4th order) of differentiation of dried polycrystalline films of peritoneal fluid – group 1 (healthy donors) and group 2 (uterus endometriosis patients) are estimated.
Influence of the coordination number Z on the micro-Raman spectra of ternary chalcogenide glasses
M. S. Iovu, O. V. Iaseniuc, D. Dinescu, et al.
Chalcogenide glasses are attractive materials due to its application in photonics and optoelectronics. Chalcogenide glasses GexAsxSe1-2x (average coordination number Z=2.15÷2.90) and (As4S3Se3)1-xSnx (average coordination number Z=2.4÷2.56), which contain elements of IV group of the Periodic Table, such as Ge and Sn are important for a wide range of technical applications, such as infrared optical elements, acousto-optic and alloptical switching devices, holographic recording media, diffractive optics, photonic crystals, etc. [1, 2]. Raman spectroscopy is an efficient method for obtaining information on the local structure of the disordered material, especially when the composition is varied. In this paper are reported the Micro-Raman spectra of GexAsxSe1-2x and (As4S3Se3)1-xSnx bulk glasses and amorphous thin films. The Micro-Raman spectra of bulk glasses and thermally deposited amorphous (As4S3Se3)1-xSnx thin films consist of two broad bands located at around ν=236 cm-1 and ν=345 cm-1, which corresponds to the symmetric stretching vibration modes of AsSe3/2 and AsS3/2 pyramids, respectively. Tin impurities didn’t change the shape of Micro-Raman spectra, but shift the both bands to low frequency region. The Micro-Raman spectra of bulk glasses and thermally deposited amorphous (GexAsxSe1-2x thin films consist of one main vibration band located at around ν=246 cm-1 for lower concentration of Ge and As, and is attributed to (AsSe1/2)3 pyramidal units. With increasing of Ge and As concentrations this band shifts to lower frequency region up to ν=236 cm-1 for x=0.30. The vibration band situated around ν=205 cm-1 is attributed to Ge(Se1/2)4 tetrahedral units and increase in the intensity with increasing of Ge and As concentrations. Some shoulders in high frequency regions at ν=365-390 cm-1 and ν=500-530 cm-1, caused by the presence of As-Se bands and Se-Se chains also was observed.
Absorption and emission spectra of Ga1.7Ge25As8.3S65 glasses doped with rare-earth ions
E. V. Lupan, O. V. Iaseniuc, V. I. Ciornea, et al.
Excellent optical properties of chalcogenide glasses make them interesting for optoelectronic devices in the visible (VIS) and, especially, in the near- and mid-infrared (NIR and MIR) spectral regions. The rare-earth (RE3+) doped Ga17Ge25As8.3S65 glasses were prepared in evacuated (~10−5 Pa) silica-glass ampoules which were heated up to 1000 °C at 2–4°C min-1, and then the melt was quenched. The absorption and photoluminescence spectra in the visible and near IR regions for GA1.7Ge25As8.3S65 doped with rare-earth RE+) ions (Sm3+, Nd3+, Pr3+, Dy3+ and co-doped with Ho3++Dy3+) are investigated. The energy transfer of the absorbed light in the broad band Urbach region of the host glass to the RE3+ ions is suggested for increasing the emission efficiency. The investigated Ga17Ge25As8.3S65 glasses doped with RE3+ ions are promising materials for optical amplifiers operating at 1300 and 1500 nm telecommunication windows.
Energy transfer of non-equidistant radiators via the nonlinear excitation mechanism inside of an optical cavity
The energy transferring between three q-bits system flying simultaneously through an optical cavity, is discussed. It is observed the migration of energy from one excited radiator with dipole forbidden transitions relatively to another two- radiators with half excitation energy of first atom. Photon entangled state between distinct atoms and their transfer is studied. These atoms in our interpretations are named, D - dipole forbidden atom, S1 and S2 - two dipole active atoms with summer energy ћɷ1 + ћɷ2 = ћɷn, ɷ1 observe the periodical transfer of energy from D- atom to ensemble of two S- atoms. This effect may be used for quantum gates processing in which the energy transfer depends on the input information. The quantum discord and entanglement for this system of q-bits was explored.
Real-time digital holographic interferometry set-up for phase gradient study in dynamic phase objects using spatial modulator
A fully digital experimental set-up for real-time digital acquisition and digital optical reconstruction of holographic sequences is presented: a He-Ne laser, a CCD camera and a Phase Only Spatial Light Modulator (SLM) area are part of the set-up. CCD registering and SLM projector are working simultaneously. Using a custom made software of our own, real-time Digital Holographic Interferometry (DHI) “fringe motion pictures” can be performed by subtracting consecutive frames from a reference one and instantly displaying the differences on the SLM illuminated with a playback wave. Phase variations of the objects can be visualized in real-time by observing the interference fringe pattern evolution.
Sensors, Microsystems, and Instruments
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Optical measurements for excitation of CdTe quantum dots
Marian Vladescu, Valentin Feies, Paul Schiopu, et al.
The paper presents the experimental results obtained using a laboratory setup installation for fluorescence excitation of CdTe QDs used as biomarkers for clinical diagnostics. Quantum Dots (QDs) made of Cadmium Telluride (CdTe), are highly fluorescent and they are used as robust biomarkers. Generally, QDs are referred to as the zero-dimensional colloidal crystals that possess strong size dependence and multi-colored luminescence properties. Along with its intrinsic features, such as sharp and symmetric emission, photo-stability and high quantum yields, QDs play a vital role in various applications, namely the identification of the chemical moieties, clinical diagnostics, optoelectronics, bio-imaging and bio-sensing1.
Smart communication with LabView
Cătălin J. Iov, Bogdan Diaconu, Mihaela Hnatiuc
The population alarm systems do not represent a new concept. Since hundreds of years ago the man used either smoke signals generated from certain upper locations, visible from long distance, getting through acoustic systems placed on high buildings, until now when mass-media channels extended the possibilities by the television and radio. However, either one of those mentioned above requested the individual to be located at the alarming moment in the area of action of the alarm. Otherwise, the message has no efficiency. This limitation is currently solved by additional communication channels such as the internet and the mobile networks. Messages are now able to be sent to the mobile screen, and the user can reply to messages either by using the short message service (SMS) or by emailing to someone, to a server, to a center. From the general pattern of alarming the population on certain events, the medical applications represent a very important field. Messages are sent from the patient to a central medical center and back to the patient. This paper focuses on the value that virtual tools developed with LabVIEW brings to us.
Design of multi-band microstrip polygonal contour filter for microwaves
Bogdan Gavriloaia, Radu Vizireanu, Octavian Fratu, et al.
The rapid growth of wireless communications requires a new generation of multifunction devices operating simultaneously under multiple communication standards, in several bands, small, robust and low cost. Microstrip technology can provide these features. An original topological structure is presented in this paper. It integrates several microstrip lines and lumped components in an asymmetric network, and has three ports. A lot of resonance frequencies occur as a result of combination between normal and degenerate propagation modes. Dual-band and three-bands can be selected, depending on the ports used. The originality of this work is to investigate a pentagonal pattern microstrip and introduces two types of perturbations given by two capacitors and a microstrip line section between the corners of the pentagon. The electric field patterns and insertion loss are calculated and provide the possibility of implementing microstrip and larger flexibility for choosing different frequency bands for wireless applications.
Development of tools and techniques for monitoring underwater artifacts
The different assessments provide information on the best methods to approach an artifact. The presence and extent of potential threats to archaeology must also be determined. In this paper we present an underwater robot, built in the laboratory, able to identify the artifact and to get it to the surface. It is an underwater remotely operated vehicle (ROV) which can be controlled remotely from the shore, a boat or a control station and communication is possible through an Ethernet cable with a maximum length of 100 m. The robot is equipped with an IP camera which sends real time images that can be accessed anywhere from within the network. The camera also has a microSD card to store the video. The methods developed for data communication between the robot and the user is present. A communication protocol between the client and server is developed to control the ROV.
Universal system for the automation of test setups
This paper presents the concept of a universal control system for automation of small test setups. The main purpose is to control the environment in which the electronic component is being tested. The system has two device types: a master device and multiple slave devices. In this control system the devices are able to communicate with each other and are able to monitor and control specific tasks or actions required in the test flow. The system can be configured using a computer application based on text input.
New approach for processing data provided by an INS/GPS system onboard a vehicle
Ana Dumitrascu, Ionut Serbanescu, Razvan D. Tamas, et al.
Due to the technology development, navigation systems are widely used in ground vehicle applications such as position prediction, safety of life, etc. It is known that a hybrid navigation system consisting of a GPS and inertial navigation system (INS) can provide a more accurate position prediction.

By applying a Method of Moments (MoM) approach on the acquired data with INS/GPS we can extract both the coordinate and important information concerning safety of life. This kind of system will be cost effective and can also be used as a black box on boats, cars, submersible ships and even on small aircrafts.
3D THz hyperspectrum applied in security check-in
We developed a measuring technology using a TDS-THz system to construct hyperspectral images of some objects, including hazardous materials. “T-rays” (the THz spectral domain of the light) have a growing importance in security and imagistic domain. Due to their property of penetrating through dielectric objects, and using non-ionizing radiations, the THz systems have become a standard for “hot-places” (airports, train stations etc.). The hyperspectral images are 3D images having 2D spatial dimension and one spectral dimension. In this way, we obtain simultaneously information about the form of the object and its molecular composition. For discriminating between substances, we must first build a database of spectra for hazardous and dangerous substances. We experiment our system on some items (among them a firecracker, a cigarette and a metal collar) and we tried to discriminate between them using the database of spectra.
Persistent scatterers detection on synthetic aperture radar images acquired by Sentinel-1 satellite
Cosmin Dănişor, Anca Popescu, Mihai Datcu
Persistent Scatterers Interferometry (PS-InSAR) has become a popular method in remote sensing because of its capability to measure terrain deformations with very high accuracy. It relies on multiple Synthetic Aperture Radar (SAR) acquisitions, to monitor points with stable proprieties over time, called Persistent Scatterers (PS)[1]. These points are unaffected by temporal decorrelation, therefore by analyzing their interferometric phase variation we can estimate the scene’s deformation rates within a given time interval. In this work, we apply two incoherent detection algorithms to identify Persistent Scatterers candidates in the city of Focșani, Romania. The first method studies the variation of targets’ intensities along the SAR acquisitions and the second method analyzes the spectral proprieties of the scatterers. The algorithms were implemented on a dataset containing 11 complex images of the region covering Buzău, Brăila and Focșani cities. Images were acquired by Sentinel-1 satellite in a time span of 5 months, from October 2014 to February 2015. The processing chain follows the requirements imposed by the new C-band SAR images delivered by the Sentinel-1 satellite (launched in April 2014) imaging in Interferometric Wide (IW) mode. Considering the particularities of the TOPS (Terrain Observation with Progressive Scans in Azimuth) imaging mode[2], special requirements had to be considered for pre-processing steps. The PS detection algorithms were implemented in Gamma RS program, a software which contains various function packages dedicated to SAR images focalization, analysis and processing.
Terahertz spectroscopic investigations of hazardous substances
M. Bojan, V. Damian, C. Fleaca, et al.
In this paper we report spectral measurements of some relatively common substances but from the hazardous category (possibly to be used like explosives or their manipulation is dangerous) in view to create a database with spectra of such substances. THz transmission spectra of some pure materials and mixed ones are also introduced. The measurements were performed using a Time-Domain system that work in the range of 0.2-4.5 THz. We develop our algorithm to obtain maximum information from the measurement and to minimize the errors.
Assessment of illumination conditions in a single-pixel imaging configuration
Single-pixel imaging based on multiplexing is a promising technique, especially in applications where 2D detectors or raster scanning imaging are not readily applicable. With this method, Hadamard masks are projected on a spatial light modulator to encode an incident scene and a signal is recorded at the photodiode detector for each of these masks. Ultimately, the image is reconstructed on the computer by applying the inverse transform matrix. Thus, various algorithms were optimized and several spatial light modulators already characterized for such a task. This work analyses the imaging quality of such a single-pixel arrangement, when various illumination conditions are used. More precisely, the main comparison is made between coherent and incoherent ("white light") illumination and between two multiplexing methods, namely Hadamard and Scanning. The quality of the images is assessed by calculating their SNR, using two relations. The results show better images are obtained with "white light" illumination for the first method and coherent one for the second.
Sensors system design for discrimination between humans and animals
The applicability areas for sensor networks vary from industrial automation, environmental observation to medical domain [1]. As the quality of life has improved, the life expectancy also increased during the last years, fact that leads to an aging of the population. It is well known that elderly people need special treatment and resources due to their decreasing capacity of self-caring. It is, thus, desirable to increase the length of independent living for this category without depriving them from the known life environment and personal habits. Another possible application is the one of child care and monitoring in closed precincts. This paper illustrates the implementation steps of a sensor network used for discriminating between the presence of a human being and of an animal that may be useful in case of medical emergency situations. The design takes into account the main challenges that may occur such as achievement of not accurate results due to the fact that children are moving much more than an adult. The basic structure is designed using Arduino platform, sensors for distance measurements, for height determination as well as DHT22 temperature sensor and sensors for motion detection and takes into account cases of walking and standing subjects. Several configurations have been tested in order to improve the relative error for discrimination between children and pet entering a room.
Cyber physical systems based on cloud computing and internet of things for energy efficiency
George Suciu, Cristina Butca, Victor Suciu, et al.
Cyber Physical Systems (CPS) and energy efficiency play a major role in the context of industry expansion. Management practices for improving efficiency in the field of energy consumption became a priority of many major industries who are inefficient in terms of exploitation costs. The effort of adopting energy management means in an organization is quite challenging due to the lack of resources and expertise. One major problem consists in the lack of knowledge for energy management and practices. This paper aims to present authors’ concept in creating a Cyber Physical Energy System (CPES) that will change organizations’ way of consuming energy, by making them aware of their use. The presented concept will consider the security of the whole system and the easy integration with the existing electric network infrastructure.
Optical investigation of electromagnetic fuel atomizers
Cornel Suciu, Marius Beniuga
The devices that ensure atomization of fluids (injectors and atomizers) are largely employed in contemporary technology. Injectors play a very important part in the functioning of various systems based on combustion of liquid fuels, such as internal combustion engines and turbines, jet engines, furnaces etc. During operation, these devices are subjected to important pressures and need to work within very strict parameters. It is therefore important to have very precise active surfaces.

The present work aimed to investigate such devices after certain degrees of usage in order to verify the evolution of surface micro-characteristics and their influence upon operating parameters. In order to achieve the abovementioned purpose, an optical evaluation of the surface was conducted using laser profilometry. Surface measurements were conducted on several injectors, after various degrees of usage, by aid of a laser profilometer equipped with a confocal sensor that has a vertical working range of 13mm and a resolution of 1μm1. After the surface micro-topography was measured, 3D and 2D representations, as well as individual profiles of the active surfaces, were analyzed and the significant parameters were determined. Surface wear and presence of combustion residues was analyzed in terms of its influence upon operating conditions.
Investigations upon the effects of an auxiliary brake system on the working parameters of diesel engines
Cornel Suciu, Ioan Mihai
Classical systems have the main disadvantage of being unable to ensure that high load diesel engine vehicles are slowed in good conditions, for the entire range of combinations of inclinations and lengths of sloped public roads. On such roads, where brakes are used repeatedly and for long periods, friction components that enter classical braking systems will overheat and lead to failure.

The present paper aims to investigate, the efficiency of a braking system based on compression release, called a Jake Brake. In such a system, the exhaust valve is actuated at a certain predetermined angle of the crankshaft.

The presented research was conducted on an experimental rig based on a four-stroke mono-cylinder diesel engine model Lombardini 6 LD400. Pressure and temperature evolutions were monitored before and during the use of the Jake Brake system. As the generated phonic pollution is the main disadvantage of such systems, noise generated in the vicinity of the engine was monitored as well. The monitored parameters were then plotted in diagrams that allowed evaluating the performances of the system.
Preparation of the cast glass-coated amorphous magnetic microwires
S. A. Baranov, O. V. Yaltychenko, E. Yu. Kanarovskii, et al.
In the present work, the cast glass-coated amorphous microwires manufactured by the Ulitovsky-Taylor method are studied. Interest in the cast glass-coated amorphous microwires has greatly increased in the last few years mainly due to their technological applications, in particular, as the sensor elements in the various devices. Technological aspects of the Ulitovsky-Taylor method for the preparation of the glass-coated microwires with the different radius are analyzed. It is essential that the microwires are manufactured using a rapid solidification technique. The geometrical characteristics of a microwire depend on the physical properties of a metal and of glass, the diameter of the initial glass tube, and the parameters of the heating inductor. The given method provides the microwire geometric parameters of within the wide ranges. Respectively, a metallic core diameter in these microwires can range from 0.5 to 70 μm, and their glass-coating thickness can be varied from 1 to 50 μm. Moreover, the length of the derivable samples can reach up to 104 m. The obtained microwires exhibit the magnetic properties, which are high dependent on the metallic core composition, and similarly as it was done here for the residual stresses, they can be expressed through the microwire geometric parameters.
Research and investigation of a communication chain on optical fiber with a Fabry-Perot power diode for the automotive industry
Irina Bristena Bacis, Alexandru Vasile, Ciprian Ionescu, et al.
The purpose of this paper is to analyze different power devices - emitters of optical flow, from the point of view of optical coupling, emitted optical powers, optical fiber losses and receiver. The research and characterization of the transmission through a power optical system is done using a computer system specialized for the automotive industry. This system/platform can deliver current pulses that are controlled by a computer through a software (it is possible to set different parameters such as pulse repetition frequency, duty cycle, and current intensity).

For the experiments a power Fabry Perot 1035 laser diode operating in pulse with μφ 1055 nm, Ith = 40 mA, and Iop =750 mA was used with a single-mode SFM 128 optical fiber and an EM type optical coupler connected through alignment. Two types of measurements were conducted to demonstrate the usefulness of the experimental structure. In the first case the amplitude of the voltage pulses was measured at the output of an optical detector with receiving diode in a built-in amplifier with a 50 kΩ load resistance. In the second stage measurements were conducted to determine the optical power injected in the optical fiber and received at the reception cell of a power meter. Another parameter of optical coupling that can be measured using the experimental structure is irradiation. This parameter is very important to determine the optimum cutting angle of the fiber for continuity welding.
Study on determining the photometric parameters for a white LED using a light meter
The paper presents the experiments performed in order to determine the most suitable measuring mode which could be used to notably increase the accuracy of the photometric parameters determination for a white LED using a light meter with multiple measurement modes for various classic light sources like tungsten (incandescent), fluorescent, mercury and sodium based. Light meters are used for measuring the illuminance, which is a photometric parameter and its determination is based on the properties of human sight sense. Knowing how the sensitivity of the eye varies with the wavelength, the spectral response of the sensor and the spectral composition of the radiation emitted by a certain light source, a correction curve can be applied over the sensed values and obtain an accurate measurement. Nowadays many light meters can contain multiple calibration curves for typical light sources, but not for LEDs, especially for white ones. Since multiple measurements can be done using each correction curve, the authors conducted experiments to determine how to combine the aforementioned results to obtain a good estimate for the illuminance of white LEDs.
Temperature measurements of high power LEDs
Niculina Badalan (Draghici), Paul Svasta, Andrei Drumea
Measurement of a LED junction temperature is very important in designing a LED lighting system. Depending on the junction temperature we will be able to determine the type of cooling system and the size of the lighting system. There are several indirect methods for junction temperature measurement. The method used in this paper is based on the thermal resistance model. The aim of this study is to identify the best device that would allow measuring the solder point temperature and the temperature on the lens of power LEDs. For this purpose four devices for measuring temperature on a high-power LED are presented and compared according to the acquired measurements: an infrared thermal camera from FLIR Systems, a multimeter with K type thermocouple (Velleman DVM4200), an infrared-spot based noncontact thermometer (Raynger ST) and a measurement system based on a digital temperature sensor (DS1821 type) connected to a PC. The measurements were conducted on an 18W COB (chip-on-board) LED. The measurement points are the supply terminals and the lens of the LED.
Data mining methods for parameters forecasting of a small solar plant
Maria Muntean, Adrian Tulbure, Corina Rotar
This paper investigates the relation between the intensity of solar radiation correlated with ambient temperature and energy production, at local scale and area, using a forecasting algorithm. In the first step, using the experimental collected data, the authors have developed a suitable model to study the analyzed phenomena. The model can be applied for forecasts in the energy sector, very useful especially because UAT (territorial administrative unit) of Alba Iulia has a 275kW functional photovoltaic park.
The influence of vibrations on time reference signals generated using quartz crystals
Andrei Drumea, Alina Marcu, Ioan Plotog
32.768 kHz low frequency crystals are found in a large part of today’s embedded systems that use microcontrollers especially in battery supplied applications which need low power consumption1]. Their main role is to offer a stable time reference. There are situations in which time measurement is needed when the system works in a mechanically unstable environment (cars, industrial equipment). The paper presents the studies done on the behavior of 32.768 kHz quartz crystals that are part of embedded systems which operate in a vibrating environment, in terms of period and long-time jitter of the generated time reference signal. The investigations of this effect were done using a test bench especially designed for this purpose which can measure the presented parameters determined by controlled mechanical stimulus (waveform, amplitude and frequency of the vibrations).
A new mechatronic set-up and technique for investigation of firearms
Ioan Lesenciuc, Cornel Suciu
Since ancient times, mankind has manifested interest in the development and improvement of weapons, either for military or hunting purposes. Today, in competition with these legal practices, the number of those who commit crimes by non-compliance with the regime of weapons and ammunition has increased exponentially. This is why the technology and methods employed in the area of judicial ballistics, requires constant research and continuous learning. The present paper advances a new experimental set-up and its corresponding methodology, meant to measure the force deployed by the firing pin. The new experimental set-up and procedure consists of a mechatronic structure, based on a piezoelectric force transducer, which allows to measure, in-situ, the force produced by the firing pin when it is deployed. The obtained information can further be used to establish a correspondence between this force and the imprint left on the firing cap. This correspondence furthers the possibility of elaborating a model that would permit ballistic experts to correctly identify a smoothbore weapon.
Analysis of power supply circuits for electroluminescent panels
Andrei Drumea, Robert Alexandru Dobre
The electroluminescent panel is a light emitting device that requires for normal operations alternative voltages with peak to peak amplitudes in 100V… 300V range and frequencies in 100Hz … 2 kHz range. Its advantages, when compared with standard light sources like incandescent lamps, gas-discharge lamps or light emitting diodes (LEDs), are lower power consumption, flexible substrate and uniform light without observable luminous points. One disadvantage of electroluminescent panels is the complex power supply required to drive them, but the continuous improvement in passive and active integrated devices for switched mode power supplies will eventually solve this issue. The present paper studies different topologies for these power supplies and the effect of the electric parameters like the amplitude, frequency, waveform of the supplying voltage on the light emission and on power consumption for electroluminescent panels with different size and colors.
Embedded systems for controlling LED matrix displays
Cristina Marghescu, Andrei Drumea
LED matrix displays are a common presence in everyday life – they can be found in trains, buses, tramways, office information tables or outdoor media. The structure of the display unit is similar for all these devices, a matrix of light emitting diodes coupled between row and column lines, but there are many options for the display controller that switches these lines. Present paper analyzes different types of embedded systems that can control the LED matrix, based on single board computers, on microcontrollers with different peripheral devices or with programmable logic devices like field programmable gate arrays with implemented soft processor cores. Scalability, easiness of implementation and costs are analyzed for all proposed solutions.
Maintenance-free super-capacitor-based WSN power supply
Super-capacitors are highly reliable devices, outlasting any existing battery in operating conditions, cycle number and ruggedness. They are perfect candidates for energy storage in remote wireless sensor network nodes. Other applications [1] use a combination of rechargeable battery as the main storage device and a low capacity EDLC as energy buffer. This paper describes the design and the results from a module consisting of a single large capacitor, a MPPC charger and a boost converter. Unlike other devices, this prototype uses one storage device (a single EDLC), it does not involve software components [2] and it can operate from a single solar cell.
Studying the thermal regime of power LEDs by using the embedded protection diode
The paper presents the experimental results obtained by using the embedded protection diode for monitoring the operating temperature of the power LEDs. The experiments have been done in both heating and cooling conditions, in order to prove the accuracy of the proposed method. Monitoring the thermal regime of power LEDs by using the embedded protection diode proved to be a viable solution.
Piezoelectric devices for generating low power
This paper reviews concepts and applications in low-power electronics and energy harvesting technologies. Various piezoelectric materials and devices for small power generators useful in renewable electricity are presented. The vibrating piezoelectric device differs from the typical electrical power source in that it has capacitive rather than inductive source impedance, and may be driven by mechanical vibrations of varying amplitude. In general, vibration energy could be converted into electrical energy using one of three techniques: electrostatic charge, magnetic fields and piezoelectric. A low power piezoelectric generator, having a PZT element was realised in order to supply small electronic elements, such as optoelectronic small devices, LEDs, electronic watches, small sensors, interferometry with lasers or Micro-electro-mechanical System (MEMS) array with multi-cantilevers.
Microphotonics and Micronanotechnologies
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Microelectronics and nanotechnology, and the fractal-like structure of information, knowledge, and science
The article is centralizing and is concentrating the information from a considerable amount of papers related to the field of microelectronics and nanotechnology and also provides an approach to science and to the future evolution of science, based on the theory of the fractals.

The new science of microelectronics and nanotechnology is one of the best examples of how the science of future will look like, namely at the confluence of increasingly more other sciences, where increasingly more sciences are to be added in the structure of the new science and the role of the multidisciplinary and interdisciplinary is becoming more and more important.

Although not giving explicit details (e.g. specific formulas) the theory of fractals is used in the paper to explain the way of generation of new science for the specific case of microelectronics and nanotechnology, but is also used in the paper to outline a different way to approach new science and eventually to approach new sciences to come.

There are mainly two motivations for the present article, namely: on the one hand, the position of the microelectronics and nanotechnologies in the fractal-like structure of science, and, on the other hand, that much of the communication, information, knowledge and science transfer, dissemination and advancement in sciences are taking place using the new technologies related to microelectronics and nanotechnologies.
Photoconductivity of amorphous GexAsxSe1-2x and (As4S3Se3)1-xSnx thin films
O. V. Iaseniuc, M. S. Iovu
Arsenic selenide glasses are well known as high photosensitive materials with a wide range of application in optoelectronics and information storage systems. Besides, it was found that the impurities influence the electrical and photoelectrical characteristics of the amorphous material, due to the changes in the density of localized states. Introduction of the elements of IV group of periodic table in selenide and sulphide glasses, such as Sn and Ge, conduct to the appearance of tetrahedral structural units in the base glass, which change the coordination number. These particularities lead on non-monotonous dependence of physical properties on the glass composition. Besides that, recently it was established, that in the disordered network of glassy system GexAsxSe1-2x exists three distinct phases, floppy, intermediate and stressed rigid, and the dependence of physical properties of the average coordination number Z. In the present paper the experimental results on steady-state photoconductivity of amorphous GexAsxSe1-2x and (As4S3Se3)1-xSnx thin films are presented and discusses. It was shown, that the spectral distribution of the stationary photoconductivity for both glass systems depends on the composition and polarity on the illuminated electrode. The experimental results are discussed in terms of multiple trapping model for amorphous materials, with exponential distribution of localized states in the band gap.
Technology and optical characterization of luminophore coordination compounds Eu(o-MBA)3Phen and NC PEPC/Eu(o-MBA)3Phen
Olga Bordian, Victor Verlan, Ion Culeac, et al.
Were obtained a new nanocomposite (NC) based on poly N-epoxy prolyl carbazol (PEPC) and the coordination compound luminophore Eu(o-MBA)3Phen, where o-MBA is o- methylbenzoic acid and Phen – phenanthroline. Nanocrystals of Eu(o-MBA)3Phen with the dimensions ~ 50 nm were uniformly incorporated into the PEPC polymer matrix with various concentrations. The absorption spectra of coordination compounds and thin layers of NC PEPC/Eu(o-MBA)3Phen revealed 1 intensive absorption bands at 2.02 eV. Photoluminescence (PL) spectra showed an intense red luminescence at 578 – 699 nm, which is assigned to the transitions 4D07Fi (i= 0,1,2 3 4) in the 4f-shell of the Eu3+ ion.
Influence of spray nozzle shape upon atomization process
Marius Beniuga, Ioan Mihai
The atomization process is affected by a number of operating parameters (pressure, viscosity, temperature, etc.) [1-6] and the adopted constructive solution. In this article are compared parameters of atomized liquid jet with two nozzles that have different lifespan, one being new and the other one out. The last statement shows that the second nozzle was monitored as time of operation on the one hand and on the other hand, two dimensional nozzles have been analyzed using laser profilometry. To compare the experimental parameters was carried an experimental stand to change the period and pulse width in injecting liquid through two nozzles. Atomized liquid jets were photographed and filmed quickly. Images obtained were analyzed using a Matlab code that allowed to determine a number of parameters that characterize an atomized jet. Knowing the conditions and operating parameters of atomized jet, will establish a new wastewater nozzle block of parameter values that can be implemented in controller that provides dosing of the liquid injected. Experimental measurements to observe the myriad forms of atomized droplets to a wide range of operating conditions, realized using the electronic control module.
Experimental investigation of micro heat pipe with extra fluid
Ioan Mihai, Siviu Sprinceana
The thermal micro pipes which were aimed to the cooling of the electrical systems, were realized until the present day in different constructive ways. If the first thermal pipes had had at the base the thermo-siphon system [1], afterwards it had been developed the thermal micro pipes [2], thanks to their increased capacity of heat dissipation of the surfaces covered by big densities of the thermal flow. The article, presents in the first part, the physical characteristics of the elements which embody a thermal micro pipe and which generates an excess of liquid. For this it has been realized an experimental setup. Measurements were taken by aid of a laser profilometer of the coverage material in two cases. The first one considered the material without being soaked in the liquid, and for the second one, the measurements were taken when the material was supersaturated with liquid. Since the setup allows for temperature monitoring, determinations were effectuated in the vaporization, adiabatic and condensation areas. The temperature field was determined along a thermal micro pipe in the case of extra fluid. The experimental determinations allowed verifying if the method proposed by Mihai and Olariu [3], for cooling of the electronic components, through a semi active method with the share of extra fluid in the vaporization area of the thermal micro pipe, works. It was studied how the temperature modifies in the vaporization and condensation areas and by the contrast of the theoretical results obtained through the evaluation with the experimental ones.
Studies concerning the effect of large droplets creation during fuel atomization
Marius Beniuga, Ioan Mihai
This paper presents how to form and evolve atomized fuel droplets obtained experimentally for a high wear injector if the injection pressure is below nominal. The emergence and development of large droplet atomization phenomenon in spark-ignition engines are considered an undesirable phenomenon. The presence of large droplets of the atomized fuel leads to the deposition of substances on the surface of the injector nozzle of the spray in the areas of the intake valve and its seat aspects of oxides which give rise to these areas. In addition, there is the possibility of harm in larger quantities than the normal atomization, in which case the operation of the engine and becomes defective. For proper engine operating at the same time ensuring economy, injection equipment must provide a fuel pressure to the maximum prescribed.

The article studied how faulty air mixture formation petrol deviations from uniformity is a due injectors waste can generate large drops of fuel. To conduct this study was conducted an experimental stand [1] which allows modification of the duration of injection and its cyclicality. To highlight the injector nozzle wear scans were performed by laser profilometry. Highlighting the large droplets of fuel was performed using rapid shootings.
Convection's enhancement in thermal micro pipes using extra fluid and shape memory material
Ioan Mihai, Siviu Sprinceana
Up to now, there have been developed various applications of thermal micro pipes[1-3], such as refrigerating systems, high heat flux electronics cooling, and biological devices etc., based on vacuum vaporization followed by a convective phenomenon that allows vapor transfer from the vaporization area to the condensation one. This article presents studies carried out on the enhancement of the convective phenomenon taking place in flat thermal micro pipes. The proposed method[4] is aimed at the cooling of power electronics components, such as microprocessors. The conducted research focused on the use of shape memory materials that allow, by a semi-active method, to bring extra fluid in the vaporization area of the thermal micro pipe. The conducted investigations analyzed the variation of the liquid layer thickness in the trapezoidal micro channels and the thermal flow change over time. The modification of liquid flow was studied in correlation with the capacity of the polysynthetic material to retain the most extra fluid in its pores. The enhancement of the convective heat transfer phenomenon in flat thermal micro pipes was investigated in correspondence to the increase of liquid quantity in the vaporization zone. The charts obtained by aid of Mathcad[5] allowed to represent the evolution during a period of time (or with the pipe’s length) of the liquid film thickness, the flow and the thermal flow, as a function of the liquid supply variation due to the shape memory materials and the modification of the working temperature.
Heat transfer at the sintered layer-polysynthetic material interface inside heat micro pipes
Siviu Sprinceana, Ioan Mihai
If micro heat pipe heat transfers, the inside working fluid goes through a biphasic state. The flow of the liquid and the vapor thereof by the capillary beds of frittered copper and the layer of capillary polysynthetic material and migration of vapors liquid from the end, takes the heat flow towards the end where a transfer of heat may occur only if there is a difference in temperature between the end of a flat micro heat pipe that gives the acquirer heat and heat flux. The porosity of the material is total pore of the total material volume. In the analysis of heat and mass transfer through porous media, both convective and conductive transfer forms can not be separated, because of the surfaces in contact between the two capillar layers. It had been studied the dependence of the rate of flow of liquid through the frittered porous media, and Reynolds polysynthetic. It tracks changes in the Reynolds number based on the interior capillary porosity. They traced in Mathcad [1] the graphs for changing the Reynolds number of capillary pressure by capillary porosity.
Heat transfer within a flat micro heat pipe with extra liquid
Silviu Sprinceana, Ioan Mihai
In the real functioning of flat micro heat pipe (FMHP), there can appear cases when the temperature from the vaporization zone can exceed a critical value caused by a sudden increase of the thermal flow. The heat transfer which is completed conductively through the copper wall of a FMHP vaporizer causes the vaporization of the work fluid. On the condenser, the condensation of the fluid vapors and the transfer of the condenser to the vaporizer can no longer be achieved. The solution proposed for enhancing heat transfer in the event of blockage phenomenon FMHP, it is the injection of a certain amount of working fluid in the vaporization zone. By this process the working fluid injected into the evaporator passes suddenly in the vapor, producing a cooling zone. The new product additional mass of vapor will leave the vaporization zone and will condense in condensation zone, thereby supplementing the amount of condensation. Thus resumes normal operating cycle of FMHP. For the experimental measurements made for the transfer of heat through the FMHP working fluid demineralized water, they were made two micro-capillary tubes of sintered copper layer. The first was filled with 1ml of demineralized water was dropped under vacuum until the internal pressure has reached a level of 1∙104Pa. The second FMHP was filled with the same amount of working fluid was used and the same capillary inner layer over which was laid a polysynthetic material that will accrue an additional amount of fluid. In this case, the internal pressure was reduced to 1∙104Pa.
Optical registration of transformer oil absorption processes in electrical pressboard nano-capillaries
The paper presents designed and built measurement system for measuring electrical pressboard oil absorption speed. During measurements the test bench allows for automatic record of oil level, time, temperature, humidity and atmospheric pressure. Measurements of Nytro Taurus oil, produced by Nynas company, absorption by pressboard, produced by Weidman company, were made.

It has been observed, that the absorption of oil takes place in three stages, duration of which are respectively τ1≈0,66 h, τ2≈109 h and τ3≈524 h. It was established that the time required to complete the oil absorption process takes more than 46 days. This means that at least as much time should take oil impregnation process of pressboard samples made for electrical measurements.
Impedance of (CoFeZr)0,559(PbZrTiO3)0,441 nanocomposite annealed in a tubular furnace
The objective of the present research has been to determine the influence of annealing in tubular furnace on capacity of (CoFeZr)0,559(PbZrTiO3)0,441 nanocomposite produced by ion beam sputtering using combined argon and oxygen beam. The phase angle of the nanocomposite directly after preparing demonstrates negative values, which indicates the capacitive type of electrical conductivity of the material. The rapid increase of conductivity when frequency increases indicates hopping conductance in the material. The additional polarization of the nanocomposite occurs with its extinction in the area of high frequencies. The electrons relaxation time has been defined as of ca τ = 1,25×10-4 s. Annealing of nanocomposite sample x = 55.9 at.% at temperature Ta = 548 K causes phase angle obtains positive values in high frequency area, which indicates the change of conduction type from capacitive to inductive. The voltage resonance phenomenon occurs in the material. Annealing in temperature of Ta = 648 K causes changes of the nanomaterials capacity. The additional oxidization of CoFeZr metallic phase nanograins which provides to the potential barrier formation around potential wells (CoFeZr nanoparticles).
The influence of strong electric fields on the DC conductivity of the composite cellulose, insulating oil, and water nanoparticles
The paper presents investigated the dependencies of DC conductivity electrical pressboard impregnated insolating oil of moisture content and electric field strength. The studies were conducted for measuring temperature in the range of 20 °C to 80 °C and the electric field intensity in the range of 10 kV/m to 1000 kV/m. With approximate waveforms in double logarithmic coordinates conductivity depending on the intensity of the electric field exponential function determined coefficients of determination R2. The value of this ratio is close to unity, which provides high accuracy measurements of conductivity and the exact stability and temperature measurements. It was found that changes in the electric field intensity will decrease the activation energy of conductivity of about 0.01 eV, thus increasing the DC conductivity of about 1.5 times.
Technological studies for plasmonic metasurfaces
Roxana Tomescu, Cristian Kusko, Adrian Dinescu, et al.
This work will present the technological processes necessary to experimentally obtain plasmonic metasurfaces for developing flat optical components or diffractive optical elements (DOE) which have reflexion functionalities. This class of metasurfaces offers the possibility to manipulate the beam shape using an array of metallic nanoscale elements patterned on a substrate.

The main feature of these structures is that one can manipulate the phase behavior by modifying some of the geometrical parameters of the nano-antennas in order to achieve the required phase shift values for the desired applications. The first important step in experimentally obtaining a plasmonic metasurface structures is the electron beam lithography (EBL) followed by the lift-off method. Due to the small sizes of the gold nano-antennas and tight periodicity of the array a number of impediments can emerge in experimentally obtaining such geometries which can be overcome by the parameter optimization of the employed technologies.
Mechanical action of the transverse spin flows in evanescent fields
Mechanical action caused by the optical forces connected with the canonical momentum density associated with the local wavevector or Belifante’s spin angular momentum, the helicity dependent and the helicity independent forces determined by spin momenta of different nature open attractive prospects to use optical structures for manipulating with minute quantities of matter that is of importance in nanophysics, nanooptics and nanotechnologies, precision chemistry and pharmacology and in numerous other areas. The main finding of our study consists in direct experimental demonstration of physical reality and mechanical action of recently discovered extraordinary transverse component of the spin angular momentum arising (in our case) in an evanescent light wave due to the total internal reflection of linearly polarized probing beam with azimuth 450 at the interface ‘birefringent plate–air’, which is oriented perpendicularly to the wave vector of an evanescent wave.
Nanomaterials and preservation mechanisms of architecture monuments
Rodica-Mariana Ion, Adrian Radu, Sofia Teodorescu, et al.
Knowledge of the chemical composition of the building materials of the monuments may help us to preserve and protect them from the pollution of our cities. The aim of this work is to characterize the materials of the walls from ancient buildings, the decay products that could be appear due to the action of pollution and a new method based on nanomaterials (hydroxyapatite -HAp) for a conservative preservation of the treated walls. Some analytical techniques have been used, as follow: X-ray fluorescence energy dispersive (EDXRF) (for the relative abundance of major, minor and trace elements), FTIR and Raman spectroscopy (for stratigraphic study of cross-sections of multi-layered materials found in wall paintings), Optical microscopy (OM), (for morphology of the wall samples). The nanomaterial suspension HAp applied on the sample surface by spraying, decreased the capillary water uptake, do not modify significantly the color of the samples and induced a reduced mass loss for the treated samples.
Doppler effect in opposite propagating modes of cavity
It is proposed a new approach in the estimation of quantum fluctuations of the electromagnetic field and Doppler effect using a model formed from two quantum modes of the cavity which propagate in opposite direction. The Doppler effect plays a significant role in the model in which an atom flies through the nodes and anti-nodes of the standing wave. It is shown that if the vacuum Rabi frequency achieves the value of Doppler shift kv, where k is the wave vector and v represents the atomic velocity, then the collective interactive and non-interactive modes of the resonator become connected. The interaction process looks like in the case of two coupled cavities in one of which is placed an atom. The comparison between the proposed approach and existing time dependent coupling model is given. In our model, it is obtained the non-zero value of quantum fluctuations in the nodes of the standing wave during the time in which atom flies through the cavity.
Analysis of curved shape micro-mirrors for on-chip communication
New ways of employing optics at the micro and nanometer scale are of interest. This study analyses the most common two micro-mirror shapes (i.e., spherical and parabolic) that can be used for on-chip communication - in conjunction with fiber optics/waveguides. The classical conic sections that can be used for micro-mirrors are described and a technological approach to design and manufacture such devices is presented. Finally an optimization of the parabolic micro-mirror is achieved. Other micro-mirror shapes (e.g., elliptical and hyperbolic) can be approached and compared using the same procedure. The large area of applications of such micro-mirrors includes intra- or inter-chips communications, as well as free-space optics used for various optical systems: micro-optics, optical amplifiers, lasers, and wavelength converters.
Modeling, Design, and Simulation
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Processing in (linear) systems with stochastic input
The paper is providing a different approach to real-world systems, such as micro and macro systems of our real life, where the man has little or no influence on the system, either not knowing the rules of the respective system or not knowing the input of the system, being thus mainly only spectator of the system’s output. In such a system, the input of the system and the laws ruling the system could be only “guessed”, based on intuition or previous knowledge of the analyzer of the respective system. But, as we will see in the paper, it exists also another, more theoretical and hence scientific way to approach the matter of the real-world systems, and this approach is mostly based on the theory related to Schrödinger’s equation and the wave function associated with it and quantum mechanics as well. The main results of the paper are regarding the utilization of the Schrödinger’s equation and related theory but also of the Quantum mechanics, in modeling real-life and real-world systems.
Computer fluid dynamics (CFD) study of a micro annular gear pump
Liviu-Constantin Stan, Ioan Călimănescu
Micro technology makes it possible to design products simply, efficiently and sustainably and at the same time, opens up the creation of new functionalities. The field of application of the micro annular gear pumps lies in analytical instrumentation, mechanical and plant engineering, chemical and pharmaceutical process engineering as well as in new markets like fuel cells or biotechnology, organic electronics or aerospace. The purpose of this paper is to investigate by using the powerful ANSYS 16 CFX module the hydrodynamic behavior of an 8/9 teeth annular gear pump. The solving of solids evolving inside fluids was very cumbersome until the advent of the Ansys immersed solid technology. By deploying this technology for very special topics like the CFD analysis of Micro annular gear pumps, credible and reliable results may be pulled leading thus the way for more in depth studies like geometrical a functional optimization of the existing devices. This paper is a valuable guide for the professionals working in the design field of micro pumps handing them a new and powerful design tool.
Computer fluid dynamics (CFD) study of a plate heat exchanger working with nanofluids
Liviu-Constantin Stan, Ioan Călimănescu
The industry fosters many types of heat exchangers such double pipe or plate heat exchangers (HX), but lately the plate HX are gaining the high ground in many applications. Such a plate HX is made out of serial plate modules packed together allowing the warm and cold fluids to pass through and exchange the heat. The paper is demonstrating the functioning of a medium sized plate HX functioning with 10% Al2O3 and water nanofluids flowing in both cold and warm sides of the HX. The influence of the nanofluid properties will be investigated as impact upon the outlet temperature of the fluid leaving the HX. Using the RSM methodology. The main conclusion of this study is that there is a balance between the nanofluids increased conductivity and their increased viscosity. The nanofluids are working well for those applications where the flow is not impeded by narrow fluid passages where the bigger influence of the viscosity is actually worsening the heat transfer conditions instead of increasing it, since the influence of viscosity in that kind of applications is three time bigger. A nanofluid conductivity threshold was also detected over which the nanofluids say with 15$ or 20% alumina content is useless for the overall heat transfer conditions.
3D simulation for solitons used in optical fibers
F. Vasile, C. M. Tebeica, P. Schiopu, et al.
In this paper is described 3D simulation for solitions used in optical fibers. In the scientific works is started from nonlinear propagation equation and the solitons represents its solutions. This paper presents the simulation of the fundamental soliton in 3D together with simulation of the second order soliton in 3D. These simulations help in the study of the optical fibers for long distances and in the interactions between the solitons. This study helps the understanding of the nonlinear propagation equation and for nonlinear waves. These 3D simulations are obtained using MATLAB programming language, and we can observe fundamental difference between the soliton and the second order/higher order soliton and in their evolution.
On the performance of variable forgetting factor recursive least-squares algorithms
Camelia Elisei-Iliescu, Constantin Paleologu, Răzvan Tamaş
The recursive least-squares (RLS) is a very popular adaptive algorithm, which is widely used in many system identification problems. The parameter that crucially influences the performance of the RLS algorithm is the forgetting factor. The value of this parameter leads to a compromise between tracking, misadjustment, and stability. In this paper, we present some insights on the performance of variable forgetting factor RLS (VFF-RLS) algorithms, in the context of system identification. Besides the classical RLS algorithm, we mainly focus on two recently proposed VFF-RLS algorithms. The novelty of the experimental setup is that we use real-world signals provided by Romanian Air Traffic Services Administration, i.e., voice and noise signals corresponding to real communication channels. In this context, the Air Traffic Control (ATC) communication represents a challenging task, usually involving non-stationary environments and stability issues.
Considerations about optimization of the flow into a blending tank
Mariana Panaitescu, Fanel-Viorel Panaitescu, Iulia-Alina Anton
In this paper is studying multi-phase fluid flow simulation in a blending tank, which involve air and water. It aims to use a model of the turbulence of the fluid, addicted to set different options for each fluid turbulence. It used for simulation the equations and tools from program ANSYS 13.0. The system is composed of a tank, a pipe of air injection, four baffles, a rotor, and a vertical shaft passing through the vessel. Data entry: the rotation frequency of the rotor on axis Ox (89 rotations/min(rpm)), the speed of the air which is injected into the container (5 m/s ), diameter pipe at entry (0.0248 m).The study assumptions are: a) the temperature of the water and the air remain constant (25 °C) and that the air is incompressible, with a density equal to that at 25 0 C and 1 Pa; b) the bubbles have 3 mm diameter. The mixture requires two domains: a domain for rotor and stationary tank area. Both areas contain water as a continuous phase and air as the dispersion phase. The fields will shape buoyancy, turbulence and the forces of the fluid. In the paper are presented the details of flow analysis for: dispersed fluid in the impeller region of mixing device and of continuous fluid in the same region, with corresponding parameters, after this for tank and the boundary conditions for each studied assumptions. Flow simulation in blending tank help to optimize the shape of tank and reducing the hydraulic losses due to fouling the solid borders.
Simulation of nonlinear electron dynamics in tetramer metal-carbon nanoclusters
O. V. Yaltychenko, E. Yu. Kanarovskii, S. A. Baranov, et al.
In this paper the simulation of nonlinear electron dynamics in the metal-carbon tetramer nanocluster was carried out using the modified approach in a framework of jellium model. The model Hamiltonian includes the terms accounting the action of external electric field and the interaction between the tunneling electron with the vibrational modes of carbon shell. As a result, the system of differential equations for the amplitudes of the electron localization probability at the MCN centers was obtained and then at the various sets of model parameters it was solved numerically. The different regimes in the electron localization dynamics were revealed and the control role of the electric field was shown.
Experimental researches of marine wave parameters in the Black Sea Basin
Fanel-Viorel Panaitescu, Mariana Panaitescu, Iulia-Alina Anton
In this paper are presented the process of measuring parameters of marine waves with performed devices which permit to obtain the values of the speed and current division marine wave amplitude and direction of the wave at each measurement, the number of measurements, date, hour, minute and second of measurement. This monitoring, which comprises the period of one year including, reveals an amplitude an annual average of the wave of hmed=1.53 m, obtained by taking maximum envelope appeared in a measurement range of 120 seconds. The value is unexpectedly high, taking into account of the fact that on the coastline it was found of: hmed =0.467 m at Constanta Station and hmed =0.23 m at Mangalia Station. These results reveal that there is a energy potential that exceeds expectations, much larger in the area of off shore, that is to say, in more than 12 Mm off shore, in front of the coastal zone. These measurements were applied with two devices-one device for measuring hidrostatic amplitude test and other device, ADV(Advanced Doppler velocymmeter).
The analysis of MAI in large scale MIMO-CDMA system
Recently, technological development imposed a rapid growth in the use of data carried by cellular services, which also implies the necessity of higher data rates and lower latency. To meet the users’ demands, it was brought into discussion a series of new data processing techniques. In this paper, we approached the MIMO technology that uses multiple antennas at the receiver and transmitter ends. To study the performances obtained by this technology, we proposed a MIMO-CDMA system, where image transmission has been used instead of random data transmission to take benefit of a larger range of quality indicators. In the simulations we increased the number of antennas, we observed how the performances of the system are modified and, based on that, we were able to make a comparison between a conventional MIMO and a Large Scale MIMO system, in terms of BER and MSSIM index, which is a metric that compares the quality of the image before transmission with the received one.
Noise analysis in power distribution systems
This paper proposes an analysis, especially in time domain, of the electrical noise existent on the power distribution lines. This study is important for the use of powerlines as a channel of information transmissions. This information may refer to analog signals and as well to digital signals. The main problem addressed in this paper consists in the characterization of the background noise and to establish his statistical proprieties. It is very important to know if the noise induced in the transmission channel is a stationary one, or even an ergodic one. The main parameters like the mean value, the mean square value were determined in this paper. The approximation of the probability density function of each statistical parameter was studied. The pulses induced in the transmission channel by the transient phenomena of the power electrical systems were considered deterministic signals and their contributions were not included in this study.
High performance genetic algorithm for VLSI circuit partitioning
Partitioning is one of the biggest challenges in computer-aided design for VLSI circuits (very large-scale integrated circuits). This work address the min-cut balanced circuit partitioning problem– dividing the graph that models the circuit into almost equal sized k sub-graphs while minimizing the number of edges cut i.e. minimizing the number of edges connecting the sub-graphs. The problem may be formulated as a combinatorial optimization problem. Experimental studies in the literature have shown the problem to be NP-hard and thus it is important to design an efficient heuristic algorithm to solve it. The approach proposed in this study is a parallel implementation of a genetic algorithm, namely an island model. The information exchange between the evolving subpopulations is modeled using a fuzzy controller, which determines an optimal balance between exploration and exploitation of the solution space. The results of simulations show that the proposed algorithm outperforms the standard sequential genetic algorithm both in terms of solution quality and convergence speed. As a direction for future study, this research can be further extended to incorporate local search operators which should include problem-specific knowledge. In addition, the adaptive configuration of mutation and crossover rates is another guidance for future research.
Time-frequency analysis of transient signals in power distribution systems
In this paper we propose an analysis of the possibilities of spikes detection which appears on the power lines of electrical distribution. The importance of this problem consists in the possibility of surveillance at distance the regimes of power electrical motors. This regime was studied in an industrial network which supplies the power pumps necessary to assures a city water consumption. We consider the industrial electrical networks as a linear, time invariant and causal system which has a certain response to the electrical spikes, assimilates with Dirac impulses. For that reason the output signal represents the impulse response of the system. The main problem is to detect this signal and to establish the moments of its presence. To detect and extract the useful signal linear methods like fourier transform or Short Time Fourier Analysis are not very relevant. A more efficient method to detect the spikes presence consists in using quadratic detectors in timefrequency domain, like detectors based on Wigner-Ville transform or detectors based on Ambiguity Function. In this paper we tried to present the advantages of these last detectors.
Supercharging an internal combustion engine by aid of a dual-rotor bi-flux axial compressor
Internal combustion engines can be supercharged in order to enhance their performances [1-3]. Engine power is proportional to the quantity of fresh fluid introduced into the cylinder. At present, the general tendency is to try to obtain actual specific powers as high as possible, for as small as possible cylinder capacity, without increasing the generated pollution hazards. The present paper investigates the impact of replacing a centrifugal turbo-compressor with an axial double-rotor bi-flux one [4]. The proposed method allows that for the same number of cylinders, an increase in discharged airflow, accompanied by a decrease in fuel consumption. Using a program developed under the MathCad environment, the present work was aimed at studying the way temperature modifies at the end of isentropic compression under supercharging conditions. Taking into account a variation between extreme limits of the ambient temperature, its influence upon the evolution of thermal load coefficient was analyzed considering the air pressure at the compressor cooling system outlet. This analysis was completed by an exergetical study of the heat evacuated through cylinder walls in supercharged engine conditions. The conducted investigation allows verification of whether significant differences can be observed between an axial, dual-rotor, bi-flux compressor and centrifugal compressors.
Influence of the cooling degree upon performances of internal combustion engine
Up to present, air cooling systems still raise several unsolved problems due to conditions imposed by the environment in terms of temperature and pollution levels. The present paper investigates the impact of the engine cooling degree upon its performances, as important specific power is desired for as low as possible fuel consumption. A technical solution advanced by the authors[1], consists of constructing a bi-flux compressor, which can enhance the engine’s performances. The bi-flux axial compressor accomplishes two major functions, that is it cools down the engine and it also turbocharges it. The present paper investigates the temperature changes corresponding to the fresh load, during the use of a bi-flux axial compressor. This compressor is economically simple, compact, and offers an optimal response at low rotational speeds of the engine, when two compression steps are used. The influence of the relative coefficient of air temperature drop upon working agent temperature at the intercooler exit is also investigated in the present work. The variation of the thermal load coefficient by report to the working agent temperature is also investigated during engine cooling. The variation of the average combustion temperature is analyzed in correlation to the thermal load coefficient and the temperatures of the working fluid at its exit from the cooling system. An exergetic analysis was conducted upon the influence of the cooling degree on the motor fluid and the gases resulted from the combustion process.
Quality engineering tools focused on high power LED driver design using boost power stages in switch mode
This paper is a part of our research dedicated to high power LED lamps designing. The boost-up selected technology wants to meet driver producers’ tendency in the frame of efficiency and disturbances constrains. In our work we used modeling and simulation tools for implementing scenarios of the driver work when some controlling functions are executed (output voltage/ current versus input voltage and fixed switching frequency, input and output electric power transfer versus switching frequency, transient inductor voltage analysis, and transient out capacitor analysis). Some electrical and thermal stress conditions are also analyzed. Based on these aspects, a high reliable power LED driver has been designed.
Modeling of the thermal comfort in vehicles using COMSOL multiphysics
Camelia Gavrila, Andreea Vartires
The environmental quality in vehicles is a very important aspect of building design and evaluation of the influence of the thermal comfort inside the car for ensuring a safe trip. The aim of this paper is to modeling and simulating the thermal comfort inside the vehicles, using COMSOL Multiphysics program, for different ventilation grilles. The objective will be the implementing innovative air diffusion grilles in a prototype vehicle. The idea behind this goal is to introduce air diffusers with a special geometry allowing improving mixing between the hot or the cold conditioned air introduced in the cockpit and the ambient.
Bistability properties of magnetic micro-nanowires
S. A. Baranov, O. V. Yaltychenko, E. Yu. Kanarovskii
A mathematical model that describes the process of the reversal magnetization of an amorphous microwire with the help of a large Barkhausen jump is proposed. The model has been estimated with regard to the optimization of the signal-tonoise ratio. Using nonlinear model, we studied the physical factors that cause the fluctuations of the start field. Based on the results of numerical experiments, the new data on the behavior of the start field under different conditions of a switching in a bistable ferromagnetic, including the conditions of high-frequency swapping, have been obtained and compared to the existing data. The results obtained do not contradict the existing physical concepts concerning a domain wall motion and are more general and realistic in a comparison with the previous model.
Mathematical modeling and simulation of a thermal system
Mirela Toropoc, Camelia Gavrila, Rodica Frunzulica, et al.
The aim of the present paper is the conception of a mathematical model and simulation of a system formed by a heatexchanger for domestic hot water preparation, a storage tank for hot water and a radiator, starting from the mathematical equations describing this system and developed using Scilab-Xcos program. The model helps to determine the evolution in time for the hot water temperature, for the return temperature in the primary circuit of the heat exchanger, for the supply temperature in the secondary circuit, the thermal power for heating and for hot water preparation to the consumer respectively. In heating systems, heat-exchangers have an important role and their performances influence the energy efficiency of the systems. In the meantime, it is very important to follow the behavior of such systems in dynamic regimes. Scilab-Xcos program can be utilized to follow the important parameters of the systems in different functioning scenarios.
Investigation of electromagnetic couplings between planar open-loop triangular-shaped resonators in microstrip and in multilayer technologies
The paper presents a study of the electromagnetic couplings between planar open-loop triangular-shaped resonators. Based on the proposed single-mode resonator, various couplings schemes are considered: between a single microstrip resonator and its 50Ω feeding line, between two identical triangular-shaped resonators designed in microstrip technology, and between pairs of synchronously-tuned resonators located on different metallization layers, in a multilayer configuration. In this last case, properly located slots, cut out in the common ground plane, ensure and control the coupling between resonators. The results shown in the paper can be used in the design of different miniature planar band-pass filters, including filters with cross-coupled resonators, in microstrip and in multilayer technologies.
Management system to a photovoltaic panel based on the measurement of short-circuit currents
This article is devoted to fundamental issues arising from operation in terms of increased energy efficiency for photovoltaic panel (PV). By measuring the current from functioning cage determine the current value prescribed amount corresponding to maximum power point results obtained by requiring proof of pregnancy with this method are the maximum energy possible, thus justifying the usefulness of this process very simple and inexpensive to implement in practice. The proposed adjustment method is much simpler and more economical than conventional methods that rely on measuring power cut.
PLM in the context of the maritime virtual education
This paper presents new approaches regarding the use of Product Lifecycle Management concept to achieve knowledge integration of the academic disciplines in the maritime education context. The philosophy of the educational system is now changing faster worldwide and it is in a continuous developing process. There is a demand to develop modern educational facilities for CAD/CAE/CAM training of the future maritime engineers, which offers collaborative environments between the academic disciplines and the teachers. It is well known that the students must understand the importance of the connectivity between the academic disciplines and the computer aided methods to interface them. Thus, besides the basic knowledge and competences acquired from the CAD courses, students learn how to increase the design productivity, to create a parametric design, the original instruments of automatic design, 3D printing methods, how to interface the CAD/CAE/CAM applications. As an example, the Strength of Materials discipline briefly presents alternate computer aided methods to compute the geometrical characteristics of the cross sections using the CAD geometry, creation the free body diagrams and presentation the deflected shapes of various educational models, including the rotational effect when the forces are not applied in the shear center, using the results of the FEM applications. During the computer aided engineering academic disciplines, after the students design and analyze a virtual 3D model they can convert it into a physical object using 3D printing method. Constanta Maritime University offers a full understanding of the concept of Product Lifecycle Management, collaborative creation, management and dissemination.
Storing wind energy into electrical accumulators
M. Dordescu, D. I. Petrescu, G. M. Erdodi
Shall be determined, in this work, the energy stored in the accumulators electrical, AE, at a wind system operating at wind speeds time-varying. mechanical energy caught in the turbine from the wind, (TV), is transformed into electrical energy by the generator synchronous with the permanent magnets, GSMP. The Generator synchronous with the permanent magnets saws, via a rectifier, energy in a battery AE, finished in a choice of two: variant 1-unregulated rectifier and variant of the 2-controlled rectifier and task adapted. Through simulation determine the differences between the two versions
Environments for online maritime simulators with cloud computing capabilities
This paper presents the cloud computing environments, network principles and methods for graphical development in realistic naval simulation, naval robotics and virtual interactions. The aim of this approach is to achieve a good simulation quality in large networked environments using open source solutions designed for educational purposes. Realistic rendering of maritime environments requires near real-time frameworks with enhanced computing capabilities during distance interactions. E-Navigation concepts coupled with the last achievements in virtual and augmented reality will enhance the overall experience leading to new developments and innovations. We have to deal with a multiprocessing situation using advanced technologies and distributed applications using remote ship scenario and automation of ship operations.
Avoiding the parametric roll
Nicoleta Acomi, Cristian Ancuţa, Cristian Andrei, et al.
Ships are mainly built to sail and transport cargo at sea. Environmental conditions and state of the sea are communicated to vessels through periodic weather forecasts. Despite officers being aware of the sea state, their sea time experience is a decisive factor when the vessel encounters severe environmental conditions. Another important factor is the loading condition of the vessel, which triggers different behaviour in similar marine environmental conditions. This paper aims to analyse the behaviour of a port container vessel in severe environmental conditions and to estimate the potential conditions of parametric roll resonance. Octopus software simulation is employed to simulate vessel motions under certain conditions of the sea, with possibility to analyse the behaviour of ships and the impact of high waves on ships due to specific wave encounter situations. The study should be regarded as a supporting tool during the decision making process.
Destructive effects induced by the electron beam in scanning electron microscopy
M. C. Popescu, B. I. Bita, M. A. Banu, et al.
The Scanning Electron Microscopy has been validated by its impressive imaging and reliable measuring as an essential characterization tool for a variety of applications and research fields. This paper is a comprehensive study dedicated to the undesirable influence of the accelerated electron beam associated with the dielectric materials, sensitive structures or inappropriate sample manipulation. Depending on the scanning conditions, the electron beam may deteriorate the investigated sample due to the extended focusing or excessive high voltage and probe current applied on vulnerable configurations. Our aim is to elaborate an instructive material for improved SEM visualization capabilities by overcoming the specific limitations of the technique. Particular examination and measuring methods are depicted along with essential preparation and manipulation procedures in order to protect the integrity of the sample. Various examples are mentioned and practical solutions are described in respect to the general use of the electron microscope.
Original data preprocessor for Femap/Nastran
Emil M. Oanta, Cornel Panait, Alexandra Raicu
Automatic data processing and visualization in the finite elements analysis of the structural problems is a long run concern in mechanical engineering. The paper presents the ‘common database’ concept according to which the same information may be accessed from an analytical model, as well as from a numerical one. In this way, input data expressed as comma-separated-value (CSV) files are loaded into the Femap/Nastran environment using original API codes, being automatically generated: the geometry of the model, the loads and the constraints. The original API computer codes are general, being possible to generate the input data of any model. In the next stages, the user may create the discretization of the model, set the boundary conditions and perform a given analysis. If additional accuracy is needed, the analyst may delete the previous discretizations and using the same information automatically loaded, other discretizations and analyses may be done. Moreover, if new more accurate information regarding the loads or constraints is acquired, they may be modelled and then implemented in the data generating program which creates the ‘common database’. This means that new more accurate models may be easily generated. Other facility consists of the opportunity to control the CSV input files, several loading scenarios being possible to be generated in Femap/Nastran. In this way, using original intelligent API instruments the analyst is focused to accurately model the phenomena and on creative aspects, the repetitive and time-consuming activities being performed by the original computer-based instruments. Using this data processing technique we apply to the best Asimov’s principle ‘minimum change required / maximum desired response’.
Original analytic solution of a half-bridge modelled as a statically indeterminate system
Emil M. Oanta, Cornel Panait, Alexandra Raicu, et al.
The paper presents an original computer based analytical model of a half-bridge belonging to a circular settling tank. The primary unknown is computed using the force method, the coefficients of the canonical equation being calculated using either the discretization of the bending moment diagram in trapezoids, or using the relations specific to the polygons. A second algorithm based on the method of initial parameters is also presented. Analyzing the new solution we came to the conclusion that most of the computer code developed for other model may be reused. The results are useful to evaluate the behavior of the structure and to compare with the results of the finite element models.
Original analytical model of the hydrodynamic loads applied on the half-bridge of a circular settling tank
Emil M. Oanta, Anca-Elena Dascalescu, Adrian Sabau
The paper presents an original analytical model of the hydrodynamic loads applied on the half-bridge of a circular settling tank. The calculus domain is defined using analytical geometry and the calculus of the local dynamic pressure is based on the radius from the center of the settling tank to the current area, i.e. the relative velocity of the fluid and the depth where the current area is located, i.e. the density of the fluid. Calculus of the local drag forces uses the discrete frontal cross sectional areas of the submerged structure in contact with the fluid. In the last stage is performed the reduction of the local drag forces in the appropriate points belonging to the main beam. This class of loads is producing the flexure of the main beam in a horizontal plane and additional twisting moments along this structure. Taking into account the hydrodynamic loads, the results of the theoretical models, i.e. the analytical model and the finite element model, may have an increased accuracy.
Natural ways to improve the power factor
The vast majority of electrical receivers, although working at nominal load, have a power factor far below neutral and then there is a need to improve the power factor by reducing reactive power and distorting power.
Using frequency converter for commanding and controlling for the rotational speed of an AC motor which acts as a motor–propeller group
Violeta-Vali Ciucur, Radu Hanzu-Pazara, Andreea Jenaru
Although the determination of propulsion machinery mass and efferent installations according to the main propulsion engine it is a method with a low degree of precision it still gives good enough results for the preliminary design stage.
Developing smart lighting LED-based device by using light parameterization and control method
The paper presents a smart system for control of chromatic distribution of white light produced by LED sources in order to satisfy simultaneously physiological comfort and color rendering requests. In region of interest (ROI) lighted by an ensemble of RGB and white LED’s, a system of appropriate light sensors (from UV to IR radiation) take the chromatic an intensity information and send them to a microcontroller based device. Following the actual state of illumination end the desired one, the microcontroller will command the LED drivers adequately to obtain the optimum situation.
Analysis and simulation of industrial distillation processes using a graphical system design model
Maria Loredana Boca, Remus Dobra, Pasculescu Dragos, et al.
The separation column used for experimentations one model can be configured in two ways: one - two columns of different diameters placed one within the other extension, and second way, one column with set diameter [1], [2]. The column separates the carbon isotopes based on the cryogenic distillation of pure carbon monoxide, which is fed at a constant flow rate as a gas through the feeding system [1],[2]. Based on numerical control systems used in virtual instrumentation was done some simulations of the distillation process in order to obtain of the isotope 13C at high concentrations. The experimental installation for cryogenic separation can be configured from the point of view of the separation column in two ways: Cascade - two columns of different diameters and placed one in the extension of the other column, and second one column with a set diameter. It is proposed that this installation is controlled to achieve data using a data acquisition tool and professional software that will process information from the isotopic column based on a logical dedicated algorithm. Classical isotopic column will be controlled automatically, and information about the main parameters will be monitored and properly display using one program. Take in consideration the very-low operating temperature, an efficient thermal isolation vacuum jacket is necessary. Since the “elementary separation ratio” [2] is very close to unity in order to raise the (13C) isotope concentration up to a desired level, a permanent counter current of the liquid-gaseous phases of the carbon monoxide is created by the main elements of the equipment: the boiler in the bottom-side of the column and the condenser in the top-side.
Numerical system for monitoring pressurized equipment
Remus Dobra, Dragos Pasculescu, Maria Loredana Boca, et al.
Electrical devices for operation in potentially explosive atmospheres are designed and built in accordance with European standard EN 50015: 1995 ex. the pressurized enclosure "p". The type of protector p, by using a protective gas in the housing is intended to prevent the formation of an explosive atmosphere within it, while maintaining an overpressure to the surrounding atmosphere and, where appropriate, by the use dilution. Research conducted for pressurized encapsulation aimed at developing new procedures for determining the parameters of pressurization to allow safe use of electrical appliances.

Pressurization with compensation for losses allegedly maintaining overpressure inside the enclosure when the outlets are closed, is made by feeding protective gas in an amount sufficient to fully compensate for losses from the housing inevitable pressurized and its associated pipework. The conditions and necessary measures that are required for appliances and equipment with potential ignition of explosive atmospheres are detailed in the SR EN 50016/2000. For pressurized encapsulation protection mode, the electric equipment can be maintained safety by the overpressure created inside them and in the supply pipes with air.

The paper presents a modern method to determine the parameters of the electric equipment with pressurization enclosures. For controlling of such equipment, a specific algorithm has been developed and laboratory tested.
A new approach in the development of quality management systems for (micro)electronics
Ioan C. Bacivarov, Angelica Bacivarov, Cătălina Gherghina
This paper presents the new approach in the analysis of the Quality Management Systems (QMS) of companies, based on the revised standard ISO 9001:2015. In the first part of the paper, QMS based on ISO 9001 certification are introduced; the changes and the updates proposed for the new version of ISO 9001:2015 are critically analyzed, based on the documents elaborated by ISO/TC 176. The approach based on ISO 9001:2015 could be considered as “beginning of a new era in development of quality management systems". A comparison between the between the "old" standard ISO 9001:2008 and the "new" standard ISO 9001:2015 is made. In the second part of the paper, steps to be followed in a company to implement this new standard are presented. A peculiar attention is given to the new concept of risk-based thinking in order to support and improve application of the process based approach. The authors conclude that, by considering risk throughout the organization the likelihood of achieving stated objectives is improved, output is more consistent and customers can be confident that they will receive the expected results. Finally, the benefits of the new approach in the development of quality management systems are outlined, as well as how they are reflected in the management of companies in general and those in electronics field, in particular. As demonstrated in this paper, well understood and properly applied, the new approach based on the revised standard ISO9001:2015 could offer a better quality management for companies operating in electronics and beyond.
Study of improving artificial lighting in industrial environments
The paper presents the work and results obtained by our team in studying the possibilities of improving the artificial lighting in industrial environments. Lighting solutions in industrial environments are mixed, a general lighting system aiming to establish enough lighting level for production halls together with a local lighting system in order to ensure a suitable lighting level for operations realized and appropriate comfort for human perception of light. These two main goals are accompanied by other objectives like energy efficiency, easy maintenance, a good ratio lifetime/price [5]. We monitored a trader of electrical wiring for automotive with continuous activity (24 hours) and based on measured level of lighting we proposed solutions aiming the completion of before mentioned targets.
Electrical and optical evaluation aspects of public lighting systems
This paper briefs a few issues regarding the technical validation of public lighting solutions. The novelty of the work is justified by the fact that it combines technical legislation in force [1], with practical analysis procedures [2]. Thus, in order to select the optimal solution, the paper describes a case study of measurement procedure which confirms the high electrical and optical characteristics [3] of the proposed solutions. At the end of the contribution, comparative design purposes for the two versions of modern street lighting are presented.
Comparative studies on dimming capabilities of retrofit LED lamps
Ciprian Ionescu, Alexandru Vasile, Norocel Codreanu, et al.
These days many variants for lighting systems are available on the market, and new solutions are about to emerge. Most of the new lamps are offered in form to be retrofitted to existing sockets and luminaires. In this paper, are presented some systematically investigations on different lamps as LEDs, Compact Fluorescent Lamps (CFLs), tungsten, and new available Cold Cathode Fluorescent Lamps (CCFLs), regarding the light level, dimming performances and also the resulting flicker and power distortion performances. The light level was expressed by the illuminance level, measured for all lamps in the same conditions, at the same distance and on the same surface represented by the photometer probe.
E-learning platform for automated testing of electronic circuits using signature analysis method
Cătălina Gherghina, Angelica Bacivarov, Ioan C. Bacivarov, et al.
Dependability of electronic circuits can be ensured only through testing of circuit modules. This is done by generating test vectors and their application to the circuit. Testability should be viewed as a concerted effort to ensure maximum efficiency throughout the product life cycle, from conception and design stage, through production to repairs during products operating. In this paper, is presented the platform developed by authors for training for testability in electronics, in general and in using signature analysis method, in particular. The platform allows highlighting the two approaches in the field namely analog and digital signature of circuits. As a part of this e-learning platform, it has been developed a database for signatures of different electronic components meant to put into the spotlight different techniques implying fault detection, and from this there were also self-repairing techniques of the systems with this kind of components. An approach for realizing self-testing circuits based on MATLAB environment and using signature analysis method is proposed. This paper analyses the benefits of signature analysis method and simulates signature analyzer performance based on the use of pseudo-random sequences, too.
Measurement strategy and analytic model to determine firing pin force
Ioan Lesenciuc, Cornel Suciu
As illustrated in literature, ballistics is a branch of theoretical mechanics, which studies the construction and working principles of firearms and ammunition, their effects, as well as the motions of projectiles and bullets1. Criminalistics identification, as part of judiciary identification represents an activity aimed at finding common traits of different objects, objectives, phenomena and beings, but more importantly, traits that differentiate each of them from similar ones2-4.

In judicial ballistics, in the case of rifled firearms it is relatively simple for experts to identify the used weapon from traces left on the projectile, as the rifling of the barrel leaves imprints on the bullet, which remain approximately identical even after the respective weapon is fired 100 times with the same barrel. However, in the case of smoothbore firearms, their identification becomes much more complicated. As the firing cap suffers alterations from being hit by the firing pin, determination of the force generated during impact creates the premises for determining the type of firearm used to shoot the respective cartridge. The present paper proposes a simple impact model that can be used to evaluate the force generated by the firing pin during its impact with the firing cap. The present research clearly showed that each rifle, by the combination of the three investigated parameters (impact force maximum value, its variation diagram, and impact time) leave a unique trace. Application of such a method in ballistics can create the perspectives for formulating clear conclusions that eliminate possible judicial errors in this field.
Harmonic distortions measured on board of a maritime vessel
Elena Zburlea, Stefan Dordea
Measurements where performed on four channels by means of an autonomous equipment (galvanic separated and not supplied from the ship’s mains) performed on board of some maritime transport vessels, inside the Port of Constanţa aquatorium.

Distorted voltages where state in the distribution panels. The sources of those distortions are the switching power supplies of the electric drives. The novelty of our work states in performing those measurements during the inside port maneuvers, when the operating time of each electric equipment is non definable. Harmonic distortions caused by the switching power converters lower the Power Factor. There is no better manner to find out the main distortions sources on board of a maritime transport vessel than to perform the measurements directly, on each location.
Streamlining the functioning of the FSO systems by choosing the optimal transmission/reception components
Viorel Manea, Sorin Puşcoci, Dan Alexandru Stoichescu
FSO systems are becoming more and more used taking under consideration the ease of installation and exploitation under the conditions of the supply of a major fraction of optical fiber bandwidth at reasonable cost. Choosing elements for manufacturing FSO transceivers must keep into account their destination. FSO transceivers can be made using LED or LASER devices at the transmission side, the reception side could be equipped with PIN or APD diodes. This paper makes an analysis of the behavior of semiconductor LASER and LED sources, as well as semiconductor devices PIN and APD for reception side, in various attenuation scenarios, with the aim of achieving an optimization of FSO transceiver, corresponding to different geographical areas, taking into account the specific area and attenuation induced by atmospheric factors, in order to obtain an optimal functioning/price ratio. In this paper it is calculated the bit error rate versus transmission distance for various combinations of sources/receivers, using the Matlab and Optiwave modeling environment, for point to point optical system communication.
Parameter extraction of an organic solar cell using asymptotic estimation and Lambert W function
Ana Bărar, Doina Mănăilă-Maximean, Octavian Dănilă, et al.
A theoretical characterization of an organic solar cell has been realized based on its equivalent model and an I-V curve corresponding to ITO/PEDOT/MEH-PPV:PCBM(1:4)/LiF/Al cell, taken from the literature. The parameters of the equivalent model have been determined using two methods: the approximation method and the Lambert W function. For the considered curve, the parameter values that have been obtained are similar to the results presented in literature. It has also been shown that the Lambert W function presents a considerably smaller error compared to the approximation method.
Optics-Inspired Approaches for Non-Optical Applications: Systems, Devices, and Signal Processing
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Propagation models for non line-of-sight scenarios
A. S. Tasu, L. Anchidin, R. Tamas, et al.
The log-normal propagation model is usually applied for scenarios including a line-of-sight path. However, there are many cases that do not include such a propagation path, e.g. indoor transmission and disaster situations, when radio waves have to penetrate trough ruins. In this paper, we show that the log-normal model can also be applied for non line-of-sight transmission. Both indoor scenario and trough-ruins scenario, are investigated.
Antenna gain measurements in the intermediate-field zone
Liliana Anchidin, Farida Bari, Ana Dumitrascu, et al.
Antenna gain is usually evaluated under far-field conditions. Furthermore, Friis transmission formula can solely be applied when antenna size can be neglected with respect to the distance between the measuring antenna and the antenna under test. In this paper, we show that by applying the distance averaging technique the far-field and antenna size constraints can be overcome. Our method was validated by measuring a monopole antenna and a Vivaldi antenna in an open area test site (OATS).
Autonomous robotic platforms for locating radio sources buried under rubble
A. S. Tasu, L. Anchidin, R. Tamas, et al.
This paper deals with the use of autonomous robotic platforms able to locate radio signal sources such as mobile phones, buried under collapsed buildings as a result of earthquakes, natural disasters, terrorism, war, etc. This technique relies on averaging position data resulting from a propagation model implemented on the platform and the data acquired by robotic platforms at the disaster site. That allows us to calculate the approximate position of radio sources buried under the rubble. Based on measurements, a radio map of the disaster site is made, very useful for locating victims and for guiding specific rubble lifting machinery, by assuming that there is a victim next to a mobile device detected by the robotic platform; by knowing the approximate position, the lifting machinery does not risk to further hurt the victims. Moreover, by knowing the positions of the victims, the reaction time is decreased, and the chances of survival for the victims buried under the rubble, are obviously increased.
A synthesis approach for antennas with a quasi-linear gain variation over a wide frequency range
Daniela Deacu, Razvan Tamas, Teodor Petrescu, et al.
In this paper, we propose to extend the frequency-domain synthesis approach based on a variable slope profile for antennas with a linear variation over a fractional bandwidth in the order of 100%. In that case the inflection point on the resulting profile is no longer located at its half. Thus, the profile shape will no longer be folded at the half, but at a coordinate closer to the end, the resulting shape approaching to a bow-tie antenna than to a circular dipole antenna.
A RF time domain approach for electric arcs detection and localization systems
Daniela Deacu, Razvan Tamas, Teodor Petrescu, et al.
In this paper we propose a new method for detection and localization of electric arcs by using two ultra-wide band (UWB) antennas together with data processing in the time-domain. The source of electric arcs is localized by computing an average on the inter-correlation functions of the signals received on two channels. By calculating the path length difference to the antennas, the direction of the electric arcs is then found. The novelty of the method consists in the spatial averaging in order to reduce the incertitude caused by the finite sampling rate.
Development and testing of an audio forensic software for enhancing speech signals masked by loud music
Robert A. Dobre, Cristian Negrescu, Dumitru Stanomir
In many situations audio recordings can decide the fate of a trial when accepted as evidence. But until they can be taken into account they must be authenticated at first, but also the quality of the targeted content (speech in most cases) must be good enough to remove any doubt. In this scope two main directions of multimedia forensics come into play: content authentication and noise reduction. This paper presents an application that is included in the latter. If someone would like to conceal their conversation, the easiest way to do it would be to turn loud the nearest audio system. In this situation, if a microphone was placed close by, the recorded signal would be apparently useless because the speech signal would be masked by the loud music signal. The paper proposes an adaptive filters based solution to remove the musical content from a previously described signal mixture in order to recover the masked vocal signal. Two adaptive filtering algorithms were tested in the proposed solution: the Normalised Least Mean Squares (NLMS) and Recursive Least Squares (RLS). Their performances in the described situation were evaluated using Simulink, compared and included in the paper.
Steganographic embedding of a secret message in a video flow
The paper presents a steganographic method which hides a secret message in a video flow. The secret message represents the result of a chaos-based encryption scheme. One of the flaws which make the algorithm unpractical for real-time applications is that, while the elements of the plain-message are represented using 8 bits (ASCII characters) the corresponding encrypted values need to be represented using 16 bits. Since the pixels of a typical image are represented using 24 bits (8 bits for each color component), each encrypted character fits in only one pixel. Moreover, since the resolution of today’s video materials is very large, the pixel previously established to carry in its evolution the hidden content will not be obvious to unaware spectators, but only to the one which knows its coordinates. In addition to the steganographic procedure, the work presents preliminary results on the degree of pseudo-randomness of video flows. The study is based upon the idea behind Lyapunov exponents. The evolution of two pixels which initially differ only by the minimum possible value (the color representation’s resolution) is followed for a large number of video frames. The distance between such points, for pseudo-random behavior, is known to evolve over time in a Gaussian manner. A Kolmogorov-Smirnov statistic is computed and illustrated in order to conclude over the provenience of the data series representing the evolution of the distance between the two initially neighboring pixels from a standard normal law.
Plasma Methods and Diagnostics Used for Surface Treatments
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Biofouling development on plasma treated samples versus layers coated samples
B. Hnatiuc, P. Exnar, A. Sabau, et al.
Biofouling is the most important cause of naval corrosion. In order to reduce the Biofouling development on naval materials as steel or resin, different new methods have been tested. These methods could help to follow the new IMO environment reglementations and they could replace few classic operations before the painting of the small ships. The replacement of these operations means a reduction in maintenance costs. Their action must influence especially the first two steps of the Biofouling development, called Microfouling, that demand about 24 hours. This work presents the comparative results of the Biofouling development on two different classic naval materials, steel and resin, for three treated samples, immersed in sea water. Non-thermal plasma, produced by GlidArc technology, is applied to the first sample, called GD. The plasma treatment was set to 10 minutes. The last two samples, called AE9 and AE10 are covered by hydrophobic layers, prepared from a special organic-inorganic sol synthesized by sol-gel method. Theoretically, because of the hydrophobic properties, the Biofouling formation must be delayed for AE9 and AE10. The Biofouling development on each treated sample was compared with a witness non-treated sample. The microbiological analyses have been done for 24 hours by epifluorescence microscopy, available for one single layer.
Evolution of the construction and performances in accordance to the applications of non-thermal plasma reactors
B. Hnatiuc, J. L. Brisset, D. Astanei, et al.
This paper aims to present the evolution of the construction and performances of non-thermal plasma reactors, identifying specific requirements for various known applications, setting out quality indicators that would allow on the one hand comparing devices that use different kinds of electrical discharges but also their rigorous classification by identification of criteria in order to choose the correct cold plasma reactors for a specific application. It briefly comments the post-discharge effect but also the current dilemma on non-thermal plasma direct treatments versus indirect treatments, using plasma activated water (PAW) or plasma activated medium (PAM), promising in cancer treatment.
Effects of GlidArc plasma treatment on metallic surface
D. Astanei, M. Ursache, E. Hnatiuc, et al.
This paper presents the GlidArc plasma effects on some metallic surfaces often used in dentistry: zirconium, titanium and nickel – chromium alloy plates. For the experiments performed, a GlidArc reactor with two planar electrodes has been used. During the tests, the gas flow has been kept constant while the treatment time and the distance between the plasma and the sample were modified. The surfaces were analyzed using atomic force microscopy (AFM) in order to determine the surface morphological modifications induced by the plasma treatment.
Long thermal interactions of PAW with normal tooth structure and different dental biomaterials
Andra-Cristina Bostănaru, Eugen Hnatiuc, Irina Roşca, et al.
Plasma activated water (PAW) has been widely considered to be an effective method for decontamination. Recently, numerous studies report that plasma-activated water (PAW) also has antibacterial ability to prevent or treat dental caries and periodontal related diseases. In this context, this study presents the first report to evaluate the plasma activated water effect on vital teeth enamel and different dental biomaterials. In this context, this study presents the first report to evaluate long thermal interactions of plasma activated water effect on vital teeth enamel and different dental biomaterials without organic substrate. The results suggest that the long-thermal of treatment with PAW of enamel without organic substrate can dissolve the apatite crystallites which are highly organized hierarchical structures.
Treatment by gliding arc of epoxy resin: preliminary analysis of surface modifications
F. Faubert, M. Wartel, N. Pellerin, et al.
Treatments with atmospheric pressure non-thermal plasma are easy to implement and inexpensive. Among them gliding arc (GlidArc) remains rarely used in surface treatment of polymers. However, it offers economic and flexible way to treat quickly large areas. In addition the choice of carrier gas makes it possible to bring the active species and other radicals allowing different types of grafting and functionalization of the treated surfaces, for example in order to apply for anti-biofouling prevention. This preliminary work includes analysis of the surface of epoxy resins by infrared spectroscopy: the different affected chemical bonds were studied depending on the duration of treatment. The degree of oxidation (the C/O ratio) is obtained by X-ray microanalysis and contact angle analysis have been performed to determinate the wettability properties of the treated surface. A spectroscopic study of the plasma allows to determine the possible active species in the different zones of the discharge.
Medical Optoelectronics
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Ionization pattern obtained in electrospray ionization or atmospheric pressure chemical ionization interfaces for authorized antidepressants in Romania
Antidepressants were found in 1950. In the 1990s there was a new generation of antidepressants. They act on the level of certain neurotransmitters extrasinpatic by its growth. After their mode of action antidepressants may be: SSRIs (Selective Serotonin Reuptake Inhibitors); (Serotonin-Norepinephrine Reuptake Inhibitors); SARIs (Serotonin Antagonist Reuptake Inhibitors); NRIs (Norepinephrine Reuptake Inhibitors); NDRIs (Norepinephrine-Dopamine Reuptake Inhibitors) NDRAs (Norepinephrine-Dopamine Releasing Agents); TCAs (Tricyclic Antidepressants); TeCAs (Tetracyclic Antidepressants); MAOIs (Monoamine Oxidase Inhibitors); agonist receptor 5-HT1A (5- hydroxytryptamine); antagonist receptor 5-HT2; SSREs (Selective Serotonin Reuptake Enhancers) and Sigma agonist receptor.

To determine the presence of antidepressants in biological products, it has been used a system HPLC-MS (High Performance Liquid Chromatography – Mass Spectrometry) Varian 12001. The system is equipped with APCI (Atmospheric Pressure Chemical Ionization) or ESI (ElectroSpray Ionization) interface. To find antidepressants in unknown samples is necessary to recognize them after mass spectrum. Because the mass spectrum it is dependent on obtaining private parameters work of HPLC-MS system, and control interfaces, the mass spectra library was filled with the mass spectra of all approved antidepressants in Romania. The paper shows the mass spectra obtained in the HPLCMS system.
Method for the determination of cobalt from biological products with graphite furnace atomic absorption spectrometer
Cobalt is a chemical element with symbol Co and atomic number 27 and atomic weight 58.93. 59 Co is the only stable cobalt isotope and the only isotope to exist naturally on Earth. Cobalt is the active center of coenzymes called cobalamin or cyanocobalamin the most common example of which is vitamin B12. Vitamin B12 deficiency can potentially cause severe and irreversible damage, especially to the brain and nervous system in the form of fatigue, depression and poor memory or even mania and psychosis. In order to study the degree of deficiency of the population with Co or the correctness of treatment with vitamin B12, a modern optoelectronic method for the determination of metals and metalloids from biological samples has been developed, Graphite Furnace – Atomic Absorption Spectrometer (GF– AAS) method is recommended. The technique is based on the fact that free atoms will absorb light at wavelengths characteristic of the element of interest. Free atoms of the chemical element can be produced from samples by the application of high temperatures. The system GF-AAS Varian used as biological samples, blood or urine that followed the digest of the organic matrix. For the investigations was used a high – performance GF-AAS with D2 – background correction system and a transversely heated graphite atomizer. As result of the use of the method are presented the concentration of Co in the blood or urine of a group of patient in Bucharest. The method is sensitive, reproducible relatively easy to apply, with a moderately costs.
Optoelectronic method for determining platinum in biological products
Simona Radu, Mihai Ionică, Radu Alexandru Macovei, et al.
Of all platinum metals, platinum has the most uses and it’s the most abundant and most easily to be processed. Its use in auto catalysts results in environmental contamination of crowded cities and high-traffic roads. In medicine, Pt is used as a cytostatic drug. In order to study the degree of contamination of the population with Pt or the correctness of treatment with Pt, it has been developed a method for its determination from urine or blood samples with a system Graphite Furnance - Atomic Absorption Spectrometer, (GF-AAS) Varian. There are presented the methods of sampling processing for blood or urine that followed the digest of the organic matrix. In the determination of the operating parameters for the system GF-AAS, was aimed the reducing of the nonanatomic absorbance by optimizing the drying temperatures, the calcination and atomization temperatures and the removal of the nonanatomic absorbance with D2 lamp. As a result of the use of the method are presented the concentrations of Pt in the blood or urine of a group of patients in Bucharest, a city with heavy traffic of vehicles. GF-AAS method presented is sensitive, reproducible, and relatively easy to apply with an acceptable cost. With this method, the concentration of Pt can be determined from blood and urine, both in order to establish the degree of contamination with Pt and for monitoring cancer therapy with platinum compounds.
Additional Paper
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Terpolymer polyrotaxanes: a promising supramolecular system as electron-transporting materials for optoelectronics
A. Farcas, A.-M. Resmerita, Angela Rotaru, et al.
Optical, electrochemical and surface-morphological properties of three terpolymer polyrotaxanes (1a, 1b and 1c) composed of 2,7-dibromo-9,9-dicyanomethylenefluorene encapsulated into γ-cyclodextrin (γCD), β- or γ-persilylated cyclodextrin (PS-γCD, PS-γCD) cavities (acceptor) and 4,4′-dibromo-4′′-methyltriphenylamine (donor) randomly distributed into 9,9-dioctylfluorene conjugated chains have been evaluated and compared to those of the reference 1. The role of the encapsulation on the thermal stability, solubility, film forming ability and transparency was also investigated. High fluorescence efficiency, almost identical normalized absorbance maximum in solution and solid-states of 1a, 1b and 1c provides the lower aggregation tendency. The fluorescence lifetimes (τ) of 1a, 1b and 1c follow a mono-exponential decay with a value τ = 1.11, 1.03 and 1.14 ns, compared with the neat 1, where a bi-exponential decay was identified. AFM studies reveal a smooth and homogenous surface morphology for polyrotaxanes than that of the reference. The electrochemical data provided that the investigated compounds exhibited n- and p-doping processes. The HOMO/LUMO energy levels 1a, 1b, 1c and 1 and in combination with the work function of anodic ITO glass substrates coated with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) (-5.2 eV) and cathodic Ca (-2.8 eV) or Al (-2.2 eV) indicate that the compounds are electrochemically accessible as electron-transporting materials.