Proceedings Volume 9290

Photonics Applications in Astronomy, Communications, Industry, and High-Energy Physics Experiments 2014

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Proceedings Volume 9290

Photonics Applications in Astronomy, Communications, Industry, and High-Energy Physics Experiments 2014

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Volume Details

Date Published: 16 December 2014
Contents: 7 Sessions, 126 Papers, 0 Presentations
Conference: Symposium on Photonics Applications in Astronomy, Communications, Industry and High-Energy Physics Experiments 2014
Volume Number: 9290

Table of Contents

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Table of Contents

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  • Front Matter: Volume 9290
  • Optics and Photonics
  • Materials and Technologies
  • Biomedical Applications
  • High Energy Physics Applications
  • Computational Intelligence
  • Electronic Systems
Front Matter: Volume 9290
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Front Matter: Volume 9290
This PDF file contains the front matter associated with SPIE Proceedings Volume 9290, including the Title Page, Copyright information, Table of Contents, and Conference Committee listing.
Optics and Photonics
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Sources of interference in passive optical networks based on multimode fibers
Lukasz Maksymiuk, Jerzy Siuzdak, Marcin Kowalczyk
Interference sources specific for multimode fiber Passive Optical network are investigated. These include modal noise, changes and instabilities of the frequency responses, and optical beat interference. All these interferences should be reduced when the number of modes propagating in fiber is increased. Since the influence of optical beat interference in multimode fiber is reduced modal noise appears to be the most important adverse effect.
Efficiency of various modulation types in Step Index Polymer Optical Fiber
Jerzy Siuzdak, Grzegorz Stepniak
Efficiency of PAM, CAP/QAM and OFDM/DMT modulation for Step Index Polymer Optical Fiber channel is analyzed theoretically. It is shown that for the same transmitted optical power and same BER they offer similar data throughputs. However, when the light source has limited dynamics the crucial factor is the peak to average power ratio of the modulating signal. This is the greatest for OFDM/DMT and smaller for CAP and PAM. Consequently, the efficiency for PAM and CAP should be comparable whereas that of DMT – inferior. This conclusion was confirmed by experimental results.
Polarization pulling based on stimulated Raman scattering for polarization division multiplexing system
Robert Cybulski, Krzysztof Perlicki
Numerical modelling of the Raman polarization attraction and amplification process in the telecommunication band around 1550 nm is presented. Possibility of achieving both polarization pulling and amplification in Polarization Division Multiplexing transmission system by exploiting the polarization dependence of stimulated Raman scattering is investigated. Analysis is made both for co- and counter- propagation configuration with standard and highly nonlinear fiber. Different input pump polarization states are tested for best polarization pulling effectiveness.
Uncertainty of EOP resulting from uncertain PMD estimation from transmitted signal
The paper concerns uncertainty of PMD Eye Opening Penalty (EOP) in an OOK fiber optic communication line that may result from the use in EOP calculations of uncertain estimates of the first order PMD. The considered PMD estimator obtains the PMD values from waveforms of transmitted signals. It is shown that non-negligible uncertainty and bias that the PMD estimates suffer from do not translate to unacceptable uncertainty of EOP calculated from the estimates. Then, practical applicability of PMD estimation from waveforms can be confirmed.
Application of the error reduction algorithm to measurement of modal power distribution in a multimode fiber
G. Stepniak
In this paper, a new highly accurate non-interferometric method of measuring the modal power distribution (MPD) in a multimode fiber is presented. In the proposed method, light intensity in the near field and the far field of the multimode fiber are measured simultaneously by two cameras and an error reduction algorithm (in the basic version: Gerchberg- Saxton) is used to derive the phase distribution, which is required for decomposition of the field in the basis of eigen-modes of the fiber. In simulations shown, the method presents excellent convergence and accuracy. The experimentally measured MPD are shown as well.
Time-domain characterization of MMF PON
G. Stepniak, L. Maksymiuk
In this paper it is shown that time domain characterization of multimode fiber links and networks has certain advantages over the more popular frequency domain method. We show that by measuring the fiber impulse responses, in addition to the frequency response measurement, we gain knowledge on the complex frequency response and (up to some extent) on the modal distribution in the fiber. The measurements results are shown for a network consisting of a 2 km OM2 fiber and multimode passive coupler in various configurations.
Automatic detection of characteristic points and form of optical signals in multiparametric capillary sensors
The time series sequence of data readings are the input for computer aided analysis of signal from the multiparametric optical capillary sensor. The time series signals have characteristic points and forms. Their analysis by trained human operators is time consuming and sometimes lacks of precision because of the presence of signal noise. The noises can be mostly rejected with advanced electronic signal processing, but the output analog signal is often modified by the electromagnetic environment and by the noise generated by electronic elements. We propose and analyze an algorithm that can be used as an automatic detector of characteristic points and form of the time series signals that are produced by the measuring head and the analog electronic units of the biodiesel fuel quality test sensor.
Infiltration of a photonic crystal fiber with cholesteric liquid crystal and blue phase
D. Poudereux, K. Orzechowski, O. Chojnowska, et al.
Photonic crystal fibers (PCF) have been selectively filled with a cholesteric liquid crystal (ChLC) with special interest in the blue phase (BP) of the liquid crystal. It has been observed thermal tuning of the guided light in the visible region. A dramatically enhance appears when the phase of the liquid crystal changes from cholesteric to blue phase I (BPI). When a thermal range of the blue phase I is achieved, no changes are observed while increasing temperature from BPI through BPII and to the isotropic phase.
Experimental video signals distribution MMF network based on IEEE 802.11 standard
Marcin Kowalczyk, Lukasz Maksymiuk, Jerzy Siuzdak
The article was focused on presentation the achievements in a scope of experimental research on transmission of digital video streams in the frame of specially realized for this purpose ROF (Radio over Fiber) network. Its construction was based on the merge of wireless IEEE 802.11 network, popularly referred as Wi-Fi, with a passive optical network PON based on multimode fibers MMF. The proposed approach can constitute interesting proposal in area of solutions in the scope of the systems monitoring extensive, within which is required covering of a large area with ensuring of a relatively high degree of immunity on the interferences transmitted signals from video IP cameras to the monitoring center and a high configuration flexibility (easily change the deployment of cameras) of such network.
Optical communication as a perspective method of exchanging data in dedicated systems
Rafał Słomski, Edward Sędek
The paper presents operation rules of wireless optical link FSO (Free Space Optics) as well as implementation limits in real conditions. The limits are mainly connected with atmospheric factors. The article takes under consideration the choosing criterions of optical emission sources and ability of implementing them. The speed transfer results of proposed optical link, working in a wavelength range 800 ÷ 900 [nm], are presented. There is mentioned an implementation possibility of such solutions in dedicated systems that takes under consideration limits of attenuation in the atmosphere and others (e.g. correct orientations of optical modules between them). There are presented two diversity methods: spatial diversity and wavelength diversity, which a main goal is to improve the stability of optical link. There is discussed an issue of hybrid solution FSO/RF that significantly increases the probability of delivering data in real weather conditions.
Using PCA in flame vision monitoring system
This paper presents comparison image classification method of co-firing biomass and pulverized coal. Defined two class of combustion: stable and unstable for three variants with different power value parameters and fixed amount biomass. Used Principal component analysis for determine the most important features that affect the state of the combustion process.
Performance characterization of the IEEE 802.11 signal transmission over a multimode fiber PON
L. Maksymiuk, J. Siuzdak
In this paper there are presented measurements concerning performance analysis of the IEEE 802.11 signal distribution over multimode fiber based passive optical network. In the paper there are addressed three main sources of impairments: modal noise, frequency response fluctuation of the multimode fiber and non-linear distortion of the signal in the receiver.
Technological aspects of producing gradient planar waveguides for LPWG structures
Tomasz Kotyczka, Roman Rogoziński
This paper presents the technological aspect of producing gradient planar waveguides for Long Period Grating Waveguide structures (LPWG). Such waveguides are produced by the Ag+↔Na+ ion exchange method in Pyrex glass. By a sequence of ion exchange technological processes the refractive profiles of waveguides (multimode area) can be produced in this glass, so that the chosen corrugation period allows the resonant coupling of power conducted in the TE0 fundamental mode to the modes of higher order. On the basis of the determined temperature dependences of diffusion coefficients of exchanged ions the conditions of preliminary diffusion, heating and secondary diffusion (ultimately giving the required refractive index profile of the waveguide) have been determined. The technological processes mentioned above have been realized. After each of these processes the measurements of effective refractive indices of modes have been carried out. A comparison of the values and of the theoretical results has been made as well.
Luminescent optical fibre sensor for UV-A detection
Piotr Miluski, Dominik Dorosz, Marcin Kochanowicz, et al.
The article presents polymer optical fibre with sensitive luminescence cladding used for ultraviolet detection. The construction of polymethyl metacrylate (PMMA) fibre coated by organic dye doped polyurethane film is presented. The Tinopal (fluorescent optical brightener) incorporated into the polyurethane coating was used as UV indicator. The chosen dye allowed to direct UV-A detection with luminescence emission in visible range. The construction and fabrication process of UV sensitive polymer fibre is shown. The experimentally obtained characteristic using Nd: YAG (355nm) is presented. The high relative sensitivity up to 0.27mW-1 was obtained. It has been pointed potential applications of fabricated senor.
Multicolor up-conversion emission in tellurite glasses co-doped with rare earth ions for white LED applications
Paweł Sienkiewicz, Anna Palkowska, Marcin Pietrzycki, et al.
In the article the glass with molar composition of 75TeO2-20ZnO-5Na2O co-doped with Yb3+/Tm3+/Ho3+ ions was fabricated by typical melt-quenching technique. Multicolour up-conversion emission at the wavelengths of 479 nm (blue), 546 nm (green) and 650 nm (red) corresponding to transitions 1G43H6 (Tm3+), 5F45I8 (Ho3+) and 5F55I8 (Ho3+), respectively have been observed under infrared excitation (λexc = 980 nm) at room temperature. Influence of molar ratio of active ions on the colour coordinates (CIE-1931) have been investigated.
New atmospheric visibility optical sensor based on correlation coding method
Tomasz Czarnecki, Grzegorz Wilczewski, Krzysztof Perlicki
In this article a new atmospheric visibility sensor design is presented. It employs an empirical link between acquired lidar backscattered signals and atmospheric visibility parameter. In particular, received backscattered beam is under the autocorrelation analysis within the defined correlation distance, thus the outcome of this procedure presents the overall characteristic of the correlation coefficients, as a function of examined space range. Specifically, significant points of interest of this characteristic are then extracted and processed in order to evaluate the atmospheric visibility parameter. In various experimental demo campaigns, under varying weather conditions, performance of the designed device was assessed. It is reported, the approximate range of reliable atmospheric visibility parameter evaluation falls into the interval of 100 to 1400 m.
Impact of the chirp and the chromatic dispersion on the high capacity single wavelength channel PolMux transmission in the 1310 nm wavelength domain
P. Mazurek, J. P. Turkiewicz
In the following work, the optimization of a high bit rate single wavelength channel PolMux transmission system working in the 1310 nm wavelength domain, is presented. Demonstrated method utilizes the interplay between the chirp effect in an electroabsorption modulator and the chromatic dispersion in an optical fibre. By means of the numerical simulations it is shown, that the value of the modulator chirp parameter α can significantly change the maximum allowable value of the accumulated dispersion from +60 ps/nm for α = 0 to +100 ps/nm for α = -0.7. Conducted experiments show that change of a data channel wavelength from 1321.2 nm to 1311.5 nm can significantly decrease the transmission related power penalty in 2×40 Gbit/s experiment with 38 km SSMF as well as 2×50 Gbit/s and 2×56 Gbit/s experiments with 25 km SSMF. Presented method can be utilized to increase the transmission distance of low complexity and high bit rate optical transmission systems like Ethernet.
Comparison of different photometric algorithms on Pi of the Sky data
Łukasz Obara, Aleksander Filip Żarnecki, Adam Zadrożny, et al.
Pi of the Sky is a system of wide field-of-view robotic telescopes, which search for short timescale astrophysical phenomena, especially for prompt optical GRB emission. The system was designed for autonomous operation, monitoring a large fraction of the sky with 12m-13m range and time resolution of the order of 1 - 100 seconds. System design and observation strategy were successfully tested with a prototype detector in Chile, operational since 2004. In July 2013 the final Pi of the Sky detector system, with 16 CCD cameras on 4 mounts, was comissioned at the INTA El Arenosillo Test Centre in Spain, resulting in a total coverage of about 6000 square degrees. LUIZA is a dedicated framework developed for efficient image processing, implemented in C++. Data analysis is divided into small, well-defined steps, which are implemented as so called processors. The framework allows to define the processor selection and their order, as well as all the required parameters at runtime, in a simple XML steering file. It was used in the presented study to compare three different photometric algorithms considered in analysis of the Pi of the Sky data. The algorithm based on the ASAS photometry was implemented in LUIZA as a sequence of three processors. First processor searches for stars in the considered images and extracts parameters of the Gaus profile describing star pointoint spread function (PSF) best. The next processor uses the PSF parameters to convolute the image with the Gaussian kernel and used to identify stars on the resulting image. In the last step the actual photometry is peformed, i.e. object brightnesses are calculated. In the presented study, results obtained from the ASAS photometry were compared with the new photometry algorithm developed within LUIZA and with the simple aperture photometry implemented previoulsly Results are presented for analysis of single images with different exposure times, as well as for stacked frames.
Summary of the Pi of the Sky photometry improving methods
Rafał Opiela, Katarzyna Małek, Lech Mankiewicz, et al.
Pi of the Sky is a system of five wide field of view robotic telescopes, which search for short timescale astrophysical phenomena, especially for prompt optical GRB emissions. The system was designed for autonomous operation, monitoring a large fraction of the sky with 12m − 13m range and time resolution of the order of 1 − 10 seconds. Five fully automatic Pi of the Sky detectors located in Spain (INTA - INTA El Arenosillo Test Centre in Mazagón, near Huelva.) and Chile (SPDA - San Pedro de Atacama Observatory.) have been observing the sky almost every night in search of rare optical phenomena. They also collect a lot of useful observations which include e.g. observations of many kinds of variable stars. To be able to draw proper conclusions from the data received, adequate quality of the data is very important. Unfortunately Pi of the Sky data is subject to systematic errors caused by various factors, such as cloud cover, seen as significant fluctuations in the number of stars observed by the detector, problems with conducting mounting, a strong background of the Moon or the passing of a bright object, e.g. a planet, near the observed star. Some of these adverse effects can be easily detected during the cataloging of individual measurements, but the quality of our data was still not satisfactory for us. In order to improve the quality of our data, we have developed two new procedures based on two different approaches. In this article we will report on these procedures, give some examples, and show how these procedures improve the quality of our data. Later we will compare developed methods, give they advantages and disadvantages and show how we can obtain the best data quality, based only on the best combination of used algorithms results. At the end of this article we will describe how these corrections improve the period detection error, what is the most important result when we want to obtain the physical parameters of the analyzed stars.
Periodic alignment of liquid crystal molecules in silica micro-capillaries
The direction of liquid crystal (LC) arrangement can be changed by different techniques. Photo-alignment method appears to be potentially the best technique to use in the case of micro–capillaries. Developing the photo-alignment method of liquid crystal molecules in silica micro–capillaries allowed to work on obtaining periodic orientation. The usage of amplitude masks in the irradiation allows to obtain a periodic alignment of molecules variable within a single sample. In this paper, the experimental results of the periodic orientations achieved are presented.
Structural waveguide co-doped with Yb3+/Tm3+ for measurement of chlorophyll concentration
Karol Czajkowski, Marcin Kochanowicz, Jacek Zmojda, et al.
In the article a system for measuring the concentration of chlorophyll in methanol solution have been developed. Microstructural waveguide co- doped with Yb3+/Tm3+ ions was used as a sensing element. The waveguide consisted of thirty-seven glass capillaries arranged hexagonally was fabricated using the stacking and drawing method. Due to the excitation of the active core by laser diode (λ=980nm), an effective energy transfer between Yb3+ and Tm3+ ions occurs. As a result, two luminescence bands at 480 nm (1G43H6) and 650 nm (1G4→3F4) were obtained. Concentration of chlorophyll methanol solution in the range from 2.75 to 13.66 [mh/dms] was measured. Linear dependence of the decrease of luminescence intensity of thulium ions on its concentration was obtained. The sensitivity of the developed system was 0.005 [1/(mg/dm3)].
Er/Yb co-doped oxy-fluoride glass-ceramics core/polymer cladding optical fibers
E. Czerska, M. Świderska
Erbium/ytterbium co-doped glasses can be applied as NIR laser sources (1.55 μm) or optical amplifiers in this range. About hundred meters of Er/Yb co-doped oxy-fluoride glass-ceramics fibers have been drawn from a glass preform followed by controlled annealing. Processing temperatures (drawing and annealing) were selected upon thermal analysis results (DTA/DSC plots). Glass-ceramic structure was confirmed by the XRD measurements. Obtained fibers show good optical properties. As a cladding material polymer material (acrylic resin) is considered due to its low deposition temperature and suitable value of refractive index.
On accuracy of holographic shape measurement method with spherical wave illumination
This paper presents the study on the accuracy of topography measurement of high numerical aperture focusing microobjects in digital holographic microscope setup. The system works in reflective configuration with spherical wave illumination. For numerical reconstruction of topography of high NA focusing microobjects we are using two algorithms: Thin Element Approximation (TEA) and Spherical Local Ray Approximation (SLRA). In this paper we show comparison of the accuracy of topography reconstruction results using these algorithms. We show superiority of SLRA method. However, to obtain accurate results two experimental conditions have to be determined: the position of point source (PS) and imaging reference plane (IRP).Therefore we simulate the effect of point source (PS) and imaging reference plane (IRP) position on the accuracy of shape calculation. Moreover we evaluate accuracy of determination of location of PS and IRP and finally present measurement result of microlens object.
Investigation of thermal and spectroscopic properties of Bi2O3-GeO2-Ga2O3-Na2O glasses doped with Er3+ ions
Tomasz Ragin, Karol Czajkowski, Jacek Żmojda, et al.
Heavy metal oxide glasses based on the Bi2O3-GeO2-Ga2O3-Na2O system doped with Er3+ ions have been presented.. The influence of glass composition on thermal stability and luminescent properties has been presented. Fabricated glass exhibits emission at 1538 nm (Er3+: 4I13/2 → 4I15/2) under 980 nm laser diode excitation. Due to different molar content of oxides in samples, various luminescence intensity was observed. High absorption cross-section allowed to determine the gain coefficient at the level of 3.47 cm-1 at the wavelength of 1538 nm. According to the results, fabricated bismuthgermanate glasses should be used for construction of optical waveguides operating in the range of near-infrared.
Nd3+, Yb3+ and Nd3+/Yb3+ - doped borosilicate glasses for luminescent thermometry
Kamil Bykowski, Artur Bruszewski, Dominik Cimaszewski, et al.
The article presents influence of temperature on luminescent properties of borosilicate glasses with molar composition: SiO2-B2O3-Al2O3-Na2O-K2O doped with Nd3+, Yb3+ and co-doped with Nd3+/Yb°3+ ions. In the range from 60 to 300°C the quenching of luminescence signal versus increase of temperature was observed. In case of glasses doped with Nd3+ and Yb3+ ions the sensitivity was determinated to be 0.0016 [1/K] at 1.06μm and 0.001 [1/K] at 1.02μm, respectively. Fabricated glass co-doped with Nd3+/Yb3+ ions is characterized by the highest sensitivity and maximum value 0.003 [1/K] was observed at the wavelength of 1020nm, corresponding to the Yb3+: 2F5/2 → 2F7/2 transition in energy levels structure of ions.
Equipment, preliminary research and research opportunities at the High Power Laser Laboratory at Institute of Plasma Physics and Laser Microfusion
M. Rosinski, A. Zaras-Szydlowska, P. Parys, et al.
The aim of this paper is to describe the newly-opened High Power Laser Laboratory (HPLL) at the Institute of Plasma Physics and Laser Microfusion (IPPLM) and presents its research possibilities in terms of the laser source and the available diagnostics. The interactions of the ultra-short laser pulses of femto to pico second duration and energies of up to 1 J with solid-state targets leads to very distinguish phenomena which can be used for investigation of exotic states of matter and to apply them for numerous technological purposes. in this goal the application of sophisticated and especially designed diagnostic systems is also needed. As the effects of interactions include the broad range of processes as acceleration of fast ions and electrons, x-rays generation and solid material modification in terms of its mechanical, physical and optical properties the research needs to use both online plasma diagnostics and the methods of post-mortem material research characterization methods. The paper presents a brief description of the laser system, the interaction vacuum chambers and the available diagnostics as well as the scientific investigation trends which can be picked up at the HPLL at the IPPLM.
Optogenetics in animal model of alcohol addiction
Maria Nalberczak, Kasia Radwanska
Our understanding of the neuronal and molecular basis of alcohol addiction is still not satisfactory. As a consequence we still miss successful therapy of alcoholism. One of the reasons for such state is the lack of appropriate animal models which would allow in-depth analysis of biological basis of addiction. Here we will present our efforts to create the animal model of alcohol addiction in the automated learning device, the IntelliCage setup. Applying this model to optogenetically modified mice with remotely controlled regulation of selected neuronal populations by light may lead to very precise identification of neuronal circuits involved in coding addiction-related behaviors.
Analysis of local heating of liquid samples in multiparametric capillary sensors
The local heating enables liquid classification in multiparametric capillary sensors. The dispersion of capillary and microheater parameters may determine the sensor action. Therefore, this paper focuses on the analysis of a local heating implemented in mentioned sensor. The microheater consist of 4H-SiC volume heating unit, alundum ceramic base and a glass capillary is modeled and simulated using CoventorWare™. We use finite element method (FEM) to determine thermo-mechanical parameters of the designed structure. Obtained results are then compared and verified with experimental research. The influences of a capillary to microheater distance and capillary’s thickness on the output results are examined.
Fibre Bragg grating for flood embankment monitoring
Konrad Markowski, Stanislau Nevar, Adam Dworzanski, et al.
In this article we present the preliminary studies for the flood embankment monitoring system based on the fibre Bragg gratings. The idea of the system is presented. The Bragg resonance shift is transformed to the change of the power detected by the standard InGaAs photodiode. The discrimination of the received power was executed by another fibre Bragg grating with different parameters. The project of the fully functional system is presented as well.
Impact of the fibre characteristics on four-wave mixing in the 1310-nm wavelength domain
Konrad Markowski, Jarosław Piotr Turkiewicz
In this article we investigate impact of the four wave mixing effect on the quality of the signal in DWDM system, that uses standard G.652 fibre as an optical medium, in the 1310 nm wavelength domain. In particular influence of the fibre parameters like attenuation, chromatic dispersion slope and effective mode area were examined. Moreover, the impact of the input signal extinction ratio was investigated. Simulation were performed as a function of the input power per channel of the modulated signal and channel spacing of the DWDM network.
Impact of fiber ring laser configuration on detection capabilities in FBG based sensor systems
Tomasz Osuch, Tomasz Kossek, Konrad Markowski
In this paper fiber ring lasers (FRL) as interrogation units for distributed fiber Bragg grating (FBG) based sensor networks are studied. In particular, two configurations of the fiber laser with erbium-doped fiber amplifier (EDFA) and semiconductor optical amplifier (SOA) as gain medium were analyzed. In the case of EDFA-based fiber interrogation systems, CW as well as active-mode locking operation were taken into account. The influence of spectral overlapping of FBGs spectra on detection capabilities of examined FRLs are presented. Experimental results show that the SOA-based fiber laser interrogation unit can operate as a multi-parametric sensing system. In turn, using an actively mode-locked fiber ring laser with an EDFA, an electronically switchable FBG based sensing system can be realized.
Inscription of the fibre Bragg gratings with femtosecond lasers
This article reviews fibre Bragg grating inscription techniques that utilizes the femtosecond laser pulse as well as properties of such structures. In particular, the two methods are presented, one that utilizes the phase mask technique, and the other one, based on the point by point inscription. Besides that, the thermal durability of such structures is presented. Moreover, complex structures are analyzed, with ablated cladding, what allows for high resolution measurements of the electromagnetic field.
Pi of the Sky preparations towards advanced gravitational detector era
Adam Zadrożny, Rafał Opiela, Łukasz Obara, et al.
Pi of the Sky telescope have taken part in gravitational wave EM follow-up project, runned by LSC-Virgo Collaboration, in its initial run in 2009-2010. Since than gravitational wave detectors are being upgraded and become operation in 2015, when the next science run is planned. The paper focuses on Pi of the Sky preparations to LSC-Virgo EM Follow-up project of gravitational wave transient candidates in 2015+ and on Pi of the Sky results of previous science run 2009-2010.
Materials and Technologies
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Analysis of laser cutting speed influence on the surface quality and shape deviation of steel parts
The results of laser cutting speed influence on the quality of machined surface, defined by the Ra roughness parameter and the shape errors, in case of machining two types of steel: i) P265GH, ii) 1.4307 are presented in the paper. Two CO2 laser cutters with maximum power of the laser beam 4000W and 3200W were used for the investigation. The characteristics of the roughness parameter Ra depending on the laser cutting speed vc are presented. The diagrams of shape deviation of the machined specimens for the greatest and lowest values of the Ra for the both laser cutters are also presented. The deviation values from the theoretical profile of the particular samples, taking into account the type of the cut-out shape profiles (circular, linear) are calculated.
Analysis of the surface roughness after the sintered carbides turning with PCD tools
This paper describes the research results of surface quality research after the sintered carbides turning by the tools with edges made of polycrystalline diamonds (PCD). The research trials were conducted for tools with different nose radii and the influence of three independent parameters (vc, f, repsilon) affecting the surface roughness were analyzed. The impact of the binder material content Co (cobalt) on the surface quality during the turning process (according to the values of surface roughness parameter Ra) is described further on. The values of vc, f, repsilon at which the smallest surface roughness (for the particular work piece materials) could be achieved were defined. Based on the ANOVA variance analysis it was possible to find different effects of the research factors on the surface roughness (for the two types of sintered carbides shafts). For the shaft with 25% Co content, the significant influence is for two parameters: the cutting speed vc and the nose radius repsilon. For the shaft with 15% Co percentage content, the significant influence is only for the nose radius repsilon.
Example of quality assurance and optimization system for super hard materials turning
This paper introduces an example of automated intelligent system for super hard materials turning process that works according to a designed algorithm. Main task of the proposed system is to supervise the super hard materials turning process (acronym: ISSSHMT - Intelligent Supervision System of Super Hard Materials Turning) with the maximal metal removal rate Qvmax, the amplitude of natural tool wear and the measurement of values that define the state of the turning process (e.g. magnitude of cutting force, surface quality, temperature in workspace). Based on the measured values it is possible to select the optimal machining parameters (vc, ap, f), for which desired surface quality and dimensional precision can be achieved for the maximal metal removal rate Qvmax. Presented system (ISSSHMT) can be used for any CNC machine – accommodation for workspace and construction of the machine. An example of NC-code program that allows using the data acquired from the ISSSHMT system by a CNC machine control unit is presented. Optimization of the process and cost cutting can be achieved with the usage of proper target functions, for products machined with required precision class.
Optical properties of C-Pd films prepared on silica substrate studied by UV-VIS-NIR spectroscopy
Radosław Belka, Mirosław Płaza, Małgorzata Suchańska, et al.
In this paper some optical properties of carbonaceous-palladium (C-Pd) thin films investigated using UV-VIS-NIR spectroscopy method are presented. Transmittance and reflectance spectra were measured in 200-3200 nm region. The shape of the spectra were depended on allotropic form of carbon (fullerene) matrix. The refractive coefficients and film thickness of studied materials has been determined based on Thin Film Interference and “envelope” methods. The optical band gap values were also estimated from absorption spectra using Tauc plot extrapolation. The results are in good agreement with experimental data obtained by spectroscopic ellipsometry.
Investigation of C-Pd films in hydrogen atmosphere using molecular spectroscopy
Radosław Belka, Małgorzata Suchańska, Mirosław Płaza, et al.
In this paper influence of hydrogen on molecular structure of carbonaceous-palladium (C-Pd) films using Raman and FTIR spectroscopy methods has been studied. The special experimental setup (gas cell) was design and realized. The spectra were measured in H2/N2 atmosphere under different gas pressure and flow rate and compared with base spectra measured in air. The noticeable influence of gas flow on intensity of some bands in FTIR spectra were observed. Understanding of role of H2 in interaction with C-Pd film needs other experimental works. Observed phenomenon can be used in construction of optical hydrogen sensor.
Properties and structure of carbon nanotubes in the system C-Ni
E. Czerwosz, J. Kęczkowska, E. Kowalska, et al.
We present results of Raman studies of CNT-Ni films obtained in two steps method. In the first step an initial nanocomposite Ni-C film (produced by PVD method) was prepared. This initial film has multiphase composite-like structure with nanograins of fullerenes, amorphous carbon and nickel. In the second step CNTs were obtained by CVD method. In this process the initial films were placed in a quartz tube reactor where pyrolysis process were performed in xylene. Decomposition of xylene at 650°C was occurred. Products of this CVD decomposition process take part in nanotubes growth on Ni nanograins. These nanograins play a role of a catalyser of the growth process. SEM observations showed that form of nanotubes obtained with the various CVD process parameters is similar. Raman studies of initial films (obtained PVD process) confirm the presence of fullerenes C60 in and some forms of graphite–like objects in the samples. Raman spectra of MWCNTs films contained: bands characteristic for carbon nanotube’s vibrations.
New applications of carbon nanostructures in microbial fuel cells (MFC)
W. Kaca, P. Żarnowiec, Justyna Kęczkowska, et al.
In the studies presented we proposed a new application for nanocomposite carbon films (C-Pd). These films were evaluated as an anode material for Microbial Fuel Cells (MFCs) used for electrical current generation. The results of characterization of C-Pd films composed of carbon and palladium nanograins were obtained using the Physical Vapor Deposition (PVD) method. The film obtained by this method exhibits a multiphase structure composed of fullerene nanograins, amorphous carbon and palladium nanocrystals. Raman Spectroscopy (RS) and scanning electron microscopy (SEM) are used to characterize the chemical composition, morphology and topography of these films. We observed, for MFC with C-Pd anode, the highest electrochemical activity and maximal voltage density - 458 mV (20,8 mV/cm2) for Proteus mirabilis, 426 mV (19,4 mV/cm2) for Pseudomonas aeruginosa and 652 mV (29,6 mV/cm2) for sewage bacteria as the microbial catalyst.
Short range order in Pd and PdO nanoparticles embedded in carbonaceous matrix studied with the XAFS spectroscopy
The short range order around Pd atoms in nanometer-size grains embedded in carbonaceous films deposited with two-step process: physical vapor deposition (PVD) followed by chemical vapour deposition (CVD) was studied. The Pd K-edge X-ray Absorption Fine Structure Spectroscopy was applied. We have found that grains obtained in a sole PVD process contained metallic fcc palladium or amorphous palladium oxide dependently on Pd concentration and duration time of process. In the oxide fraction a short range order around Pd atoms was strongly reduced as compared to a reference PdO powder. Subsequent CVD resulted in pure Pd fcc crystallites. The accompanying annealing was found to predominantly determine the content and structure of formed Pd grains.
Analysis of machining accuracy during free form surface milling simulation for different milling strategies
The analysis results of machining accuracy after the free form surface milling simulations (based on machining EN AW- 7075 alloys) for different machining strategies (Level Z, Radial, Square, Circular) are presented in the work. Particular milling simulations were performed using CAD/CAM Esprit software. The accuracy of obtained allowance is defined as a difference between the theoretical surface of work piece element (the surface designed in CAD software) and the machined surface after a milling simulation. The difference between two surfaces describes a value of roughness, which is as the result of tool shape mapping on the machined surface. Accuracy of the left allowance notifies in direct way a surface quality after the finish machining. Described methodology of usage CAD/CAM software can to let improve a time design of machining process for a free form surface milling by a 5-axis CNC milling machine with omitting to perform the item on a milling machine in order to measure the machining accuracy for the selected strategies and cutting data.
Effective conductivity in two-dimensional two-component structures: macroscopic isotropy
Piotr Kowalczyk, Włodzimierz Bielski, Adam Idzik
In this paper we use the mathematical methods of the homogenization theory to model the electrical conductivity of a two component nanostructure. We consider here a nanocomposite material in the form of a thin plate of negligible thickness compared to the diameter. Hence we assume that our problem is two-dimensional. As an example of such material we choose a carbon-palladium nanocomposite. We use the homogenization theory to study our problem, because of a complex microgeometry of the nanostructures. We show that the effective coefficient, under some assumptions, may be equal to a geometric mean of the coefficients of both components.
Changes of electrical properties of C-Pd films due to hydrogen presence: automation of measurements
Sławomir Krawczyk, Anna Kamińska
Nanocomposite carbonaceous-palladium (C-Pd) films are promising materials for hydrogen and hydrogen compounds sensors. It is connected with highly selective hydrogen absorption by palladium nanocrystallites. Nanostructural C-Pd films were deposited on alundum substrate with silver electrodes. These C-Pd films were prepared in physical vacuum deposition (PVD) process and were characterized by scanning electron microscope (SEM). A special measurement set-up was built to study the changes of C-Pd film resistance in gas presence.
Electron microscopy studies of CNT layers
Mirosław Kozłowski, Joanna Radomska, Halina Wronka, et al.
SEM and TEM use in an investigation of CNT-Ni layers different properties is shown. We present the possibilities of using different SEM modes (SE - secondary electrons, LABE - low angle backscattered electrons) for studies of C-Ni and CNT-Ni layers topography, morphology and cross-sectional investigations (adhesion, pores size and shape, uniformity). Correlation between concentration of Ni in studied layers and technological parameters as well as in a case of CNT-Ni films correlations of Ni concentration and a diameter of carbon nanotubes are discussed. TEM studies concentrate on structure of Ni nanograins in C-Ni layers and CNT-Ni layers, CNT structure and defects, nanoonion structure. We present methods of determination of graphite plane number in MWCNTs, distance between these planes, role of catalyst position in CNT growth and interaction between catalyst and substrate. EDS method for qualitative analysis of Ni catalyst in these layers was also presented.
Field emission from carbon nanotube films deposited on etched Si
I. Stępińska, J. Radomska, H. Wronka, et al.
Field emission from carbon nanotubes films prepared on etched silicon is presented. The etched Si surface has hillockslike form. CNTs films were obtained in two-step method consisting of physical vapor deposition and chemical vapor deposition. For some samples CNTs growth mainly on the top of the hillocks. Field emission from these structures were observed and emission current (at 25 V/μm ) was 0.01-0.03mA. The current – voltage characteristics and an interpretation of observed emission were performed on base of Fowler- Nordheim theory. The short-term stability measurement of emission were also performed.
Carbon-palladium films as gas sensors (hydrogen, ammonia, methane)
Joanna Rymarczyk, Anna Kamińska, Sławomir Krawczyk
In this paper we present the results of the resistances changes of carbon-palladium films under the influences of gas like hydrogen, ammonia and methane. Our research has shown that carbon-palladium films (C-Pd films) according to the form and the structure in which they appear, they can respond to a variety of gases. The C-Pd film obtained by Physical Vapor Deposition (PVD) method is sensitive to hydrogen and do not respond to the ammonia. Thermal modification of the C-Pd film in Chemical Vapor Deposition (CVD) process affects the morphology of the film, increases its resistance and it causes that this film begins to react to the ammonia. This change causes that this film stops responding on hydrogen. Film sensitive to methane was obtained by changing the technology conditions of the PVD process. The reaction of C-Pd film on the hydrogen and the ammonia is increase resistance, while film sensitive to methane reacts by decrease of initial resistance value. In both cases, the changes are reversible after cleaning by air atmosphere. Different varieties of C-Pd films can be used to build selective sensors for hydrogen, ammonia and methane.
Spectroscopic study of ns-laser pulse interaction with Co:TiC sample
E. Kowalska-Strzęciwilk, D. Strzęciwilk, W. Skrzeczanowski, et al.
The paper presents the results of investigation of the effects of the irradiation parameters on the microstructure and surface in-situ Co-TiC composites obtained by the high temperature solution method (HTS). The obtained ingots were irradiated with Nd:YAG laser pulses (Quantel Brio, 4ns, 70mJ@1.06μm, focused with a lens of the focal length of 10 cm in air conditions. Microstructure of the laser irradiated in-situ Co-TiC composites was characterized by the Hirox digital microscope systems which made possible to observe a 3D microscopic images of the composite surface and structural changes after the series of laser irradiation. The study of melted crater ratio has been done on Co–TiC composites to investigate the effect of irradiation on composite surface microstructure. According to experimental results and analysis, it was shown that the observed craters on surfaces were deepened with increasing numbers of laser shot. On the other hand, heterogeneity of samples had influence on the depth of the crater.
Biomedical Applications
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Telemetric measurement system of beehive environment conditions
This work presents a measurement system of beehive environmental conditions. The purpose of the device is to perform measurements of parameters such as ambient temperature, atmospheric pressure, internal temperature, humidity and sound level. The measured values were transferred to the MySQL database, which is located on an external server, with the use of GPRS protocol. A website presents the measurement data in the form of tables and graphs. The study also shows exemplary results of environmental conditions measurements recorded in the beehive by hour cycle.
Algorithm of detecting structural variations in DNA sequences
Katarzyna Nałęcz-Charkiewicz, Robert Nowak
Whole genome sequencing enables to use the longest common subsequence algorithm to detect genetic structure variations. We propose to search position of short unique fragments, genetic markers, to achieve acceptable time and space complexity. The markers are generated by algorithms searching the genetic sequence or its Fourier transformation. The presented methods are checked on structural variations generated in silico on bacterial genomes giving the comparable or better results than other solutions.
K-nearest neighbors clustering algorithm
Dariusz Gauza, Anna Żukowska, Robert Nowak
Cluster analysis, understood as unattended method of assigning objects to groups solely on the basis of their measured characteristics, is the common method to analyze DNA microarray data. Our proposal is to classify the results of one nearest neighbors algorithm (1NN). The presented method well cope with complex, multidimensional data, where the number of groups is properly identified. The numerical experiments on benchmark microarray data shows that presented algorithm give a better results than k-means clustering.
Computational structural variation discovery in genomes: state of the art and challenges
Paweł Osipowski, Magdalena Pawełkowicz, Zbigniew Przybecki
Identifying structural variations is crucial to obtain comprehensive knowledge on genomic differentiation. Massive data generated by present technologies determines researchers to make use of computational methods for variation discovery in genomes. Focusing on results and trying to specify challenges remained and possible solutions for the future, here we give a review of state-of-the-art methods and software utilized for structural variation discovery.
Virtual instrument based measurement system for analysis of static and dynamic characteristics of temperature transducers
The present work shows the structure of a measurement system dedicated to examine static and dynamic characteristics of sensors used to measure temperature. The measurement system was built on the basis of a set of signal conditioners connected with a data acquisition card built in a PC. The data acquisition was completed with the use of a virtual measurement device developed in the LabVIEW environment. A was used as the source of reference temperature. During the experiments, the sensors were submersed in water of given temperature with the use of a computer controlled arm. The article also presents the results of the calibration procedure which was carried out, as well as selected application schemes.
The discrepancies in the results of bioinformatics tools for genomic structural annotation
Magdalena Pawełkowicz, Robert Nowak, Paweł Osipowski, et al.
A major focus of sequencing project is to identify genes in genomes. However it is necessary to define the variety of genes and the criteria for identifying them. In this work we present discrepancies and dependencies from the application of different bioinformatic programs for structural annotation performed on the cucumber data set from Polish Consortium of Cucumber Genome Sequencing. We use Fgenesh, GenScan and GeneMark to automated structural annotation, the results have been compared to reference annotation.
Computer program for analysis of hemodynamic response to head-up tilt test
Eliza Świątek, Gerard Cybulski, Edward Koźluk, et al.
The aim of this work was to create a computer program, written in the MATLAB environment, which enables the visualization and analysis of hemodynamic parameters recorded during a passive tilt test using the CNS Task Force Monitor System. The application was created to help in the assessment of the relationship between the values and dynamics of changes of the selected parameters and the risk of orthostatic syncope. The signal analysis included: R-R intervals (RRI), heart rate (HR), systolic blood pressure (sBP), diastolic blood pressure (dBP), mean blood pressure (mBP), stroke volume (SV), stroke index (SI), cardiac output (CO), cardiac index (CI), total peripheral resistance (TPR), total peripheral resistance index (TPRI), ventricular ejection time (LVET) and thoracic fluid content (TFC). The program enables the user to visualize waveforms for a selected parameter and to perform smoothing with selected moving average parameters. It allows one to construct the graph of means for any range, and the Poincare plot for a selected time range. The program automatically determines the average value of the parameter before tilt, its minimum and maximum value immediately after changing positions and the times of their occurrence. It is possible to correct the automatically detected points manually. For the RR interval, it determines the acceleration index (AI) and the brake index (BI). It is possible to save calculated values to an XLS with a name specified by user. The application has a user-friendly graphical interface and can run on a computer that has no MATLAB software.
Computer program for analysis of impedance cardiography signals enabling manual correction of points detected automatically
Justyna Oleksiak, Gerard Cybulski
The aim of this work was to create a computer program, written in LabVIEW, which enables the visualization and analysis of hemodynamic parameters. It allows the user to import data collected using ReoMonitor, an ambulatory monitoring impedance cardiography (AICG) device. The data include one channel of the ECG and one channel of the first derivative of the impedance signal (dz/dt) sampled at 200Hz and the base impedance signal (Z0) sampled every 8s. The program consist of two parts: a bioscope allowing the presentation of traces (ECG, AICG, Z0) and an analytical portion enabling the detection of characteristic points on the signals and automatic calculation of hemodynamic parameters. The detection of characteristic points in both signals is done automatically, with the option to make manual corrections, which may be necessary to avoid “false positive” recognitions. This application is used to determine the values of basic hemodynamic variables: pre-ejection period (PEP), left ventricular ejection time (LVET), stroke volume (SV), cardiac output (CO), and heart rate (HR). It leaves room for further development of additional features, for both the analysis panel and the data acquisition function.
Ankle Brachial Index: simple non-invasive estimation of peripheral artery disease
Marcin Pieniak, Krzysztof Cieślicki, Marek Żyliński, et al.
According to international guidelines, patients with Peripheral Artery Disease (PAD) are burdened with high cardiovascular risk. One of the simplest, non-invasive methods for PAD detection is the ankle-brachial index (ABI) measurement. The ABI is calculated as the ratio of systolic blood pressure at the ankle (pressure in the posterior tibial artery or the dorsal artery) to the systolic pressure in the arm (in the brachial artery) when the body is in a horizontal position. The physiological value of the ABI is assumed to be between 1 and 1.3; however, these limits vary from study to study. A value less than 0.9 indicates PAD. Some authors propose also measuring the ABI on both sides of the body to highlight possible differences in blood pressure between the opposite arterial segments. The aim of this study was to perform a meta-analysis of the ABI diagnostic criteria used in different publications. Additionally, ABI measurements were performed on 19 healthy patients in age ranged from 20 to 63 years. The results showed a slight dependence between age and the differences between the values obtained from left and right sides of the body.
Exploring EEG signals in a Brain-Computer Interface
Paweł Zubrycki, Jan Mulawka
This article shows the basic methods of electroencephalography EEG signal exploration. It contains information about data acquisition and different methods in which brain-computer interfaces can be made. The main focus of the paper is to find a way to determine the best set of parameters to detect movement of a hand in EEG signal. In the introduction there is also short introduction to EEG as well as fundamentals of support vector machine.
Selection of physiological parameters for optoelectronic system supporting behavioral therapy of autistic children
A. Landowska, K. Karpienko, M. Wróbel, et al.
In this article the procedure of selection of physiological parameters for optoelectronic system supporting behavioral therapy of autistic children is proposed. Authors designed and conducted an experiment in which a group of 30 health volunteers (16 females and 14 males) were examined. Under controlled conditions people were exposed to a stressful situation caused by the picture or sound (1kHz constant sound, which was gradually silenced and finished with a shot sound). For each of volunteers, a set of physiological parameters were recorded, including: skin conductance, heart rate, peripheral temperature, respiration rate and electromyography. The selected characteristics were measured in different locations in order to choose the most suitable one for the designed therapy supporting system. The bio-statistical analysis allowed us to discern the proper physiological parameters that are most associated to changes due to emotional state of a patient, such as: skin conductance, temperatures and respiration rate. This allowed us to design optoelectronic sensors network for supporting behavioral therapy of children with autism.
Asymmetry functions of joint angles in the human gait
José Carlos Lara Gómez, Jacek Dusza
The idea of this project is to study the asymmetry during human walking on some important angles. For this purpose, asymmetry functions have been developed. Until this moment, the asymmetry on these angles has been studied like something global with the asymmetry coefficients (for example, just taking the best value of asymmetry for every angle). With the asymmetry functions it is possible to study this asymmetry along the whole. Knowing this information, it could be possible to determine different anomalies depending on the angle and on the moment of the asymmetry. The ultimate goal is to obtain a computer program to perform the asymmetry functions at different angles from data obtained from patients.
Neuroengineering control and regulation of behavior
A. Wróbel, C. Radzewicz, L. Mankiewicz, et al.
To monitor neuronal circuits involved in emotional modulation of sensory processing we proposed a plan to establish novel research techniques combining recent biological, technical and analytical discoveries. The project was granted by National Science Center and we started to build a new experimental model for studying the selected circuits of genetically marked and behaviorally activated neurons. To achieve this goal we will combine the pioneering, interdisciplinary expertise of four Polish institutions: (i) the Nencki Institute of Experimental Biology (Polish Academy of Sciences) will deliver the expertise on genetically modified mice and rats, mapping of the neuronal circuits activated by behavior, monitoring complex behaviors measured in the IntelliCage system, electrophysiological brain activity recordings by multielectrodes in behaving animals, analysis and modeling of behavioral and electrophysiological data; (ii) the AGH University of Science and Technology (Faculty of Physics and Applied Computer Sciences) will use its experience in high-throughput electronics to build multichannel systems for recording the brain activity of behaving animals; (iii) the University of Warsaw (Faculty of Physics) and (iv) the Center for Theoretical Physics (Polish Academy of Sciences) will construct optoelectronic device for remote control of opto-animals produced in the Nencki Institute based on the unique experience in laser sources, studies of light propagation and its interaction with condensed media, wireless medical robotic systems, fast readout opto-electronics with control software and micromechanics.
Influence of unilateral weight on bilateral cyclograms
Juan José Pellicer Costa, Jacek J. Dusza
The paper presents the results of gait parameters as a function of unilateral weight. The object of the research was a woman walking on a stationary surface and carrying in his hand weights from 0 to 15 kg. Her movement was recorded by 6 cameras recording the location of 34 markers placed at appropriate points in the body. 3D reconstruction was performed for each of the reflecting markers. Tested signals were changes in the value the joint angles of ankle, knee and hip. On the basis of about 6 cycles of movement of each load, a model for the average gait cycle was developed. The result of the experiments are graphs of changes the joint angles as a function of time, bilateral cyclograms, synchronized bilateral cyclograms and regression lines. The conclusion of the study is to determine how one-sided load affects gait asymmetry. Simple and easy to interpret method of presentation of results were also shown. Studies were conducted using VICON system.
Symmetrical gait descriptions
Adam Dunajewski, Jacek J. Dusza, Alfredo Rosado Muñoz
The article presents a proposal for the description of human gait as a periodic and symmetric process. Firstly, the data for researches was obtained in the Laboratory of Group SATI in the School of Engineering of University of Valencia. Then, the periodical model – Mean Double Step (MDS) was made. Finally, on the basis of MDS, the symmetrical models – Left Mean Double Step and Right Mean Double Step (LMDS and RMDS) could be created. The method of various functional extensions was used. Symmetrical gait models can be used to calculate the coefficients of asymmetry at any time or phase of the gait. In this way it is possible to create asymmetry, function which better describes human gait dysfunction. The paper also describes an algorithm for calculating symmetric models, and shows exemplary results based on the experimental data.
WP1: transgenic opto-animals
E. Użarowska, Rafał Czajkowski, W. Konopka
We aim to create a set of genetic tools where permanent opsin expression (ChR or NpHR) is precisely limited to the population of neurons that express immediate early gene c-fos during a specific temporal window of behavioral training. Since the c-fos gene is only expressed in neurons that form experience-dependent ensemble, this approach will result in specific labeling of a small subset of cells that create memory trace for the learned behavior. To this end we employ two alternative inducible gene expression systems: Tet Expression System and Cre/lox System. In both cases, the temporal window for opsin induction is controlled pharmacologically, by doxycycline or tamoxifen, respectively. Both systems will be used for creating lines of transgenic animals.
Analysis of neural networks in subcortical visual structures using correlation methods
Andrzej T. Foik, Jan Popiołkiewicz, Katarzyna Żeber, et al.
Correlation methods were used to characterize the activity of single neurons and network connections in three subcortical structures of the cat visual system. Autocorrelation analysis performed on spike trains of single cells recorded from the lateral geniculate and perigeniculate nuclei showed the presence of bursts of high-frequency oscillations ranging from 100 to 550 Hz in their spontaneous activity. Autocorrelation performed on spike trains of single cells recorded from the superior colliculus also revealed oscillations, but in the frequency range of 10 - 90 Hz, both in the spontaneous and visually evoked neuronal activity. The presence of oscillations was confirmed with spectral analysis and a shift predictor was used to distinguish between stimulus-locked and stimulus-independent oscillations in visually evoked activities. Additionally, a crosscorrelation analysis performed on two spike trains recorded from the same electrode or pairs of electrodes in the superior colliculus, revealed a common input from an external source and the presence of inhibitory interactions in the neuronal network.
Genomes correction and assembling: present methods and tools
Michał Wojcieszek, Magdalena Pawełkowicz, Robert Nowak, et al.
Recent rapid development of next generation sequencing (NGS) technologies provided significant impact into genomics field of study enabling implementation of many de novo sequencing projects of new species which was previously confined by technological costs. Along with advancement of NGS there was need for adjustment in assembly programs. New algorithms must cope with massive amounts of data computation in reasonable time limits and processing power and hardware is also an important factor. In this paper, we address the issue of assembly pipeline for de novo genome assembly provided by programs presently available for scientist both as commercial and as open – source software. The implementation of four different approaches – Greedy, Overlap – Layout – Consensus (OLC), De Bruijn and Integrated resulting in variation of performance is the main focus of our discussion with additional insight into issue of short and long reads correction.
Application of statistical mining in healthcare data management for allergic diseases
Zbigniew M. Wawrzyniak, Sara Martínez Santolaya
The paper aims to discuss data mining techniques based on statistical tools in medical data management in case of long-term diseases. The data collected from a population survey is the source for reasoning and identifying disease processes responsible for patient's illness and its symptoms, and prescribing a knowledge and decisions in course of action to correct patient's condition. The case considered as a sample of constructive approach to data management is a dependence of allergic diseases of chronic nature on some symptoms and environmental conditions. The knowledge summarized in a systematic way as accumulated experience constitutes to an experiential simplified model of the diseases with feature space constructed of small set of indicators. We have presented the model of disease-symptom-opinion with knowledge discovery for data management in healthcare. The feature is evident that the model is purely data-driven to evaluate the knowledge of the diseases` processes and probability dependence of future disease events on symptoms and other attributes. The example done from the outcomes of the survey of long-term (chronic) disease shows that a small set of core indicators as 4 or more symptoms and opinions could be very helpful in reflecting health status change over disease causes. Furthermore, the data driven understanding of the mechanisms of diseases gives physicians the basis for choices of treatment what outlines the need of data governance in this research domain of discovered knowledge from surveys.
Distributed control network for optogenetic experiments
Nowadays optogenetic experiments are constructed to examine social behavioural relations in groups of animals. A novel concept of implantable device with distributed control network and advanced positioning capabilities is proposed. It is based on wireless energy transfer technology, micro-power radio interface and advanced signal processing.
Cataract influence on iris recognition performance
This paper presents the experimental study revealing weaker performance of the automatic iris recognition methods for cataract-affected eyes when compared to healthy eyes. There is little research on the topic, mostly incorporating scarce databases that are often deficient in images representing more than one illness. We built our own database, acquiring 1288 eye images of 37 patients of the Medical University of Warsaw. Those images represent several common ocular diseases, such as cataract, along with less ordinary conditions, such as iris pattern alterations derived from illness or eye trauma. Images were captured in near-infrared light (used in biometrics) and for selected cases also in visible light (used in ophthalmological diagnosis). Since cataract is a disorder that is most populated by samples in the database, in this paper we focus solely on this illness. To assess the extent of the performance deterioration we use three iris recognition methodologies (commercial and academic solutions) to calculate genuine match scores for healthy eyes and those influenced by cataract. Results show a significant degradation in iris recognition reliability manifesting by worsening the genuine scores in all three matchers used in this study (12% of genuine score increase for an academic matcher, up to 175% of genuine score increase obtained for an example commercial matcher). This increase in genuine scores affected the final false non-match rate in two matchers. To our best knowledge this is the only study of such kind that employs more than one iris matcher, and analyzes the iris image segmentation as a potential source of decreased reliability
Age and gender-invariant features of handwritten signatures for verification systems
Sura AbdAli, Joanna Putz-Leszczynska
Handwritten signature is one of the most natural biometrics, the study of human physiological and behavioral patterns. Behavioral biometrics includes signatures that may be different due to its owner gender or age because of intrinsic or extrinsic factors. This paper presents the results of the author’s research on age and gender influence on verification factors. The experiments in this research were conducted using a database that contains signatures and their associated metadata. The used algorithm is based on the universal forgery feature idea, where the global classifier is able to classify a signature as a genuine one or, as a forgery, without the actual knowledge of the signature template and its owner. Additionally, the reduction of the dimensionality with the MRMR method is discussed.
IntelliCages and automated assessment of learning in group-housed mice
Alicja Puścian, Ewelina Knapska
IntelliCage is a fully automated, computer controlled system, which can be used for long-term monitoring of behavior of group-housed mice. Using standardized experimental protocols we can assess cognitive abilities and behavioral flexibility in appetitively and aversively motivated tasks, as well as measure social influences on learning of the subjects. We have also identified groups of neurons specifically activated by appetitively and aversively motivated learning within the amygdala, function of which we are going to investigate optogenetically in the future.
High Energy Physics Applications
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Data processing boards design for CBM experiment
This paper presents a concept of the Data Processing Boards for the Compressed Baryonic Matter (CBM) experiment. Described is the evolution of the concepts leading from the functional requirements of the control and readout systems of the CBM experiment to the design of prototype implementation of the DPB boards. The paper describes requirements on the board level and on the crate level. Finally it discusses the prototype design prepared for testing and verification of proposed solutions, and selection of the final implementation.
Python based integration of GEM detector electronics with JET data acquisition system
This paper presents the system integrating the dedicated measurement and control electronic systems for Gas Electron Multiplier (GEM) detectors with the Control and Data Acquisition system (CODAS) in the JET facility in Culham, England. The presented system performs the high level procedures necessary to calibrate the GEM detector and to protect it against possible malfunctions or dangerous changes in operating conditions. The system also allows control of the GEM detectors from CODAS, setting of their parameters, checking their state, starting the plasma measurement and to reading the results. The system has been implemented using the Python language, using the advanced libraries for implementation of network communication protocols, for object based hardware management and for data processing.
FPGA implementation of overlap MTF trigger: preliminary study
Wojciech M. Zabołotny, Dominik Bartkiewicz, Michał Bluj, et al.
The paper presents the concept of the Overlap Muon Track Finder (OTF) trigger for the CMS experiment in CERN as a system implemented in the modern FPGA device. The parametrized description of the complex data processing system, allowing further optimization by iterative simulations and recompilations, is presented. Problems associated with synthesis of such complex systems with currently available synthesis tools, and their workarounds are described.
Machine optics studies for the LHC measurements
Maciej Trzebiński
In this work the properties of scattered protons in the vicinity of the ATLAS Interaction Point (IP1) for various LHC optics settings are discussed. Firstly, the beam elements installed around IP1 are presented. Then the ATLAS forward detector systems: Absolute Luminosity For ATLAS (ALFA) and ATLAS Forward Protons (AFP) are described and their similarities and differences are discussed. Next, the various optics used at Large Hadron Collider (LHC) are described and the beam divergence and width at the Interaction Point as well as at the ATLAS forward detectors locations are calculated. Finally, the geometric acceptance of the ATLAS forward detectors is shown and the impact of the LHC collimators on it is discussed.
Computer methods for ITER–like materials LIBS diagnostics
Recent development of Laser–Induced Breakdown Spectroscopy (LIBS) caused that this method is considered as the most promising for future diagnostic applications for characterization of the deposited materials in the International Thermonuclear Experimental Reactor (ITER), which is currently under construction. In this article the basics of LIBS are shortly discussed and the software for spectra analyzing is presented. The main software function is to analyze measured spectra with respect to the certain element lines presence. Some program operation results are presented. Correct results for graphite and aluminum are obtained although identification of tungsten lines is a problem. The reason for this is low tungsten lines intensity, and thus low signal to noise ratio of the measured signal. In the second part artificial neural networks (ANNs) as the next step for LIBS spectra analyzing are proposed. The idea is focused on multilayer perceptron network (MLP) with backpropagation learning method. The potential of ANNs for data processing was proved through application in several LIBS–related domains, e.g. differentiating ancient Greek ceramics (discussed). The idea is to apply an ANN for determination of W, Al, C presence on ITER–like plasma–facing materials.
Interface and protocol development for STS read-out ASIC in the CBM experiment at FAIR
Krzysztof Kasinski, Wojciech Zabolotny, Robert Szczygiel
This paper presents a proposal of a protocol for communication between the read-out integrated circuit for the STS (Silicon Tracking System) and the Data Processing Board (DPB) at CBM (Compressed Baryonic Matter) experiment at FAIR, GSI (Helmholtzzentrum fuer Schwerionenforschung GmbH) in Germany. The application background, objectives and proposed solution is presented.
Diagnostic-management system and test pulse acquisition for WEST plasma measurement system
A. Wojenski, G. Kasprowicz, K. T. Pozniak, et al.
This paper describes current status of electronics, firmware and software development for new plasma measurement system for use in WEST facility. The system allows to perform two dimensional plasma visualization (in time) with spectrum measurement. The analog front-end is connected to Gas Electron Multiplier detector (GEM detector). The system architecture have high data throughput due to use of PCI-Express interface, Gigabit Transceivers and sampling frequency of ADC integrated circuits. The hardware is based on several years of experience in building X-ray spectrometer system for Joint European Torus (JET) facility. Data streaming is done using Artix7 FPGA devices. The system in basic configuration can work with up to 256 channels, while the maximum number of measurement channels is 2048. Advanced firmware for the FPGA is required in order to perform high speed data streaming and analog signal sampling. Diagnostic system management has been developed in order to configure measurement system, perform necessary calibration and prepare hardware for data acquisition.
Data acquisition methods for GEM detectors
Andrzej Wojenski, Grzegorz Kasprowicz, Krzysztof T Poźniak, et al.
This paper overviews various methods of data acquisition from GEM detectors. Presented are currently working systems in tokamaks. The data acquisition methods are divided into two parts. First part, devoted to analog signal processing , describes different approaches for signals acquisition, i.e. pulse amplifying and shaping, ASIC use, delay lines. Digital data acquisition part describes presently used high speed interfaces and system standards. Described are also different approaches for data handling, i.e. online analysis, data reduction, system topologies.
Data management software concept for WEST plasma measurement system
This paper describes the concept of data management software for the multichannel readout system for the GEM detector used in WEST Plasma experiment. The proposed system consists of three separate communication channels: fast data channel, diagnostics channel, slow data channel. Fast data channel is provided by the FPGA with integrated ARM cores providing direct readout data from Analog Front Ends through 10GbE with short, guaranteed intervals. Slow data channel is provided by multiple, fast CPUs after data processing with detailed readout data with use of GNU/Linux OS and appropriate software. Diagnostic channel provides detailed feedback for control purposes.
3D imaging of nuclear reactions using GEM TPC
Jan Stefan Bihałowicz, Mikołaj Ćwiok, Wojciech Dominik, et al.
We present a prototype of time projection chamber with planar electronic readout. The particular aspect of the readout is the arrangement and connection of pads in three linear arrays. A track of an ionizing particle may be reconstructed by applying the specially developed algorithms to the signals generated simultaneously in the three linear arrays of strips rotated by 60°. This provides the measurement of the coordinates of the track segment corresponding to the defined time slice in the plane perpendicular to the drift vector. The relative coordinate in the orthogonal direction is provided by the measurement of time sequence of signals at the known drift velocity value. It is expected to achieve comparable precision of 3D reconstruction of charged tracks in nuclear reactions at low energies as for the pixel readout but with significantly reduced costs of electronics. In this work the results of the first experiments using this TPC are presented. The reconstructed tracks of α particles from decay of 222Rn using simple algorithm are shown. The encouraging results confirm the capability of such TPC to measure low-energy charged products of nuclear reactions and nuclear decays.
Probing heavy-ion collisions with jets in the CMS experiment
Bożena Boimska
An overview of selected results on jet physics in heavy-ion collisions from the Compact Muon Solenoid experiment at the LHC accelerator is presented. The results were obtained for lead-lead, proton-lead and proton-proton collisions collected in the years 2010 - 2013. The jet-quenching phenomenon was studied by looking at the production of so-called “hard probes”, that is high transverse momentum charged particles, prompt photons, Z and W bosons, and jets.
On precision measurement of the LHC absolute luminosity
M. W. Krasny, J. Chwastowski, A. Cyz, et al.
In this paper a method of a precise measurement of the LHC absolute luminosity is introduced. The method expoilts the unlike sign lepton pair production in the two-photon process. A brief discussion of the kinematic region optimisation, proposed detector model as well as the event selection scheme is given.
Fast modular data acquisition system for GEM-2D detector
G. Kasprowicz, Adrian Byszuk, A. Wojeński, et al.
A novel approach to two dimensional Gas Electron Multiplier (GEM) detector readout is presented. Unlike commonly used methods, based on discriminators and analogue FIFOs, the method developed uses simulta- neously sampling high speed ADCs with fast hybrid integrator and advanced FPGA-based processing logic to estimate the energy of every single photon. Such a method is applied to every GEM strip / pixel signal. It is especially useful in case of crystal-based spectrometers for soft X-rays, 2D imaging for plasma tomography and all these applications where energy resolution of every single photon is required. For the purpose of the detector readout, a novel, highly modular and extendable conception of the measurement platform was developed. It is evolution of already deployed measurement system for JET Spectrometer.
Melting and evaporation of materials exposed to intensive plasma flux
Grzegorz Pełka, Włodzimierz Stępniewski
This article describes the way to simulate interaction of a highly intensive plasma flux (of the type common in plasma focus devices) with materials. We apply 1D model of a target, assume a simple screening model of the plate by evaporated material. Moving, rigid computational mesh and enthalpy picture applied allow convenient and precise description of phase transitions in the sample. Intensive plasma bombardment causes destruction of the sample surface by melting and evaporation. The stronger the flux, the more heat is used to evaporate the sample and less is absorbed. The code purpose is to help extrapolate experimental plasma focus results to thermonuclear fusion devices.
Serial data acquisition for GEM-2D detector
Piotr Kolasinski, Krzysztof T. Pozniak, Tomasz Czarski, et al.
This article debates about data fast acquisition and histogramming method for the X-ray GEM detector. The whole process of histogramming is performed by FPGA chips (Spartan-6 series from Xilinx). The results of the histogramming process are stored in an internal FPGA memory and then sent to PC. In PC data is merged and processed by MATLAB. The structure of firmware functionality implemented in the FPGAs is described. Examples of test measurements and results are presented.
Data processing and analysis for 2D imaging GEM detector system
The Triple Gas Electron Multiplier (T-GEM) is presented as soft X-ray (SXR) energy and position sensitive detector for high-resolution X-ray diagnostics of magnetic confinement fusion plasmas [1]. Multi-channel measurement system and essential data processing for X-ray energy and position recognition is consider. Several modes of data acquisition are introduced depending on processing division for hardware and software components. Typical measuring issues aredeliberated for enhancement of data quality. Fundamental output characteristics are presented for one and two dimensional detector structure. Representative results for reference X-ray source and tokamak plasma are demonstrated.
Development of 2D imaging of SXR plasma radiation by means of GEM detectors
M. Chernyshova, T. Czarski, S. Jabłoński, et al.
Presented 2D gaseous detector system has been developed and designed to provide energy resolved fast dynamic plasma radiation imaging in the soft X-Ray region with 0.1 kHz exposure frequency for online, made in real time, data acquisition (DAQ) mode. The detection structure is based on triple Gas Electron Multiplier (GEM) amplification structure followed by the pixel readout electrode. The efficiency of detecting unit was adjusted for the radiation energy region of tungsten in high-temperature plasma, the main candidate for the plasma facing material for future thermonuclear reactors. Here we present preliminary laboratory results and detector parameters obtained for the developed system. The operational characteristics and conditions of the detector were designed to work in the X-Ray range of 2-17 keV. The detector linearity was checked using the fluorescence lines of different elements and was found to be sufficient for good photon energy reconstruction. Images of two sources through various screens were performed with an X-Ray laboratory source and 55Fe source showing a good imaging capability. Finally offline stream-handling data acquisition mode has been developed for the detecting system with timing down to the ADC sampling frequency rate (~13 ns), up to 2.5 MHz of exposure frequency, which could pave the way to invaluable physics information about plasma dynamics due to very good time resolving ability. Here we present results of studied spatial resolution and imaging properties of the detector for conditions of laboratory moderate counting rates and high gain.
Thermonuclear land of plenty
Since the process of energy production in the stars has been identified as the thermonuclear fusion, this mechanism has been proclaimed as a future, extremely modern, reliable and safe for sustaining energetic needs of the humankind. However, the idea itself was rather straightforward and the first attempts to harness thermonuclear reactions have been taken yet in 40s of the twentieth century, it quickly appeared that physical and technical problems of domesticating exotic high temperature medium known as plasma are far from being trivial. Though technical developments as lasers, superconductors or advanced semiconductor electronics and computers gave significant contribution for the development of the thermonuclear fusion reactors, for a very long time their efficient performance was out of reach of technology. Years of the scientific progress brought the conclusions that for the development of the thermonuclear power plants an enormous interdisciplinary effort is needed in many fields of science covering not only plasma physics but also material research, superconductors, lasers, advanced diagnostic systems (e.g. spectroscopy, interferometry, scattering techniques, etc.) with huge amounts of data to be processed, cryogenics, measurement-control systems, automatics, robotics, nanotechnology, etc. Due to the sophistication of the problems with plasma control and plasma material interactions only such a combination of the research effort can give a positive output which can assure the energy needs of our civilization. In this paper the problems of thermonuclear technology are briefly outlined and it is shown why this domain can be a broad field for the experts dealing with electronics, optoelectronics, programming and numerical simulations, who at first glance can have nothing common with the plasma or nuclear physics.
The fast beam condition monitor BCM1F backend electronics upgraded MicroTCA-based architecture
Agnieszka A. Zagozdzinska, Alan Bell, Anne E. Dabrowski, et al.
The Beam Radiation Instrumentation and Luminosity Project of the CMS experiment, consists of several beam monitoring systems. One system, the upgraded Fast Beams Condition Monitor, is based on 24 single crystal CVD diamonds with a double-pad sensor metallization and a custom designed readout. Signals for real-time monitoring are transmitted to the counting room, where they are received and processed by new back-end electronics designed to extract information on LHC collision, beam induced background and activation products. The Slow Control Driver is designed for the front-end electronics configuration and control. The system architecture and the upgrade status will be presented.
CMS physics highlights
Małgorzata Kazana
The CMS experiment have been built to study high-energy proton-proton and heavy-ion collisions at the LHC accelerator. The first phase of data taking in 2011-12 with provided precise measurements of numerous Standard Model observables and a wide range of searches for new phenomena. In the main, a new scalar particle has been discovered by the CMS and ALTAS experiments in 2012. Properties of the new particle are in agreement with predictions for the Higgs boson particle from the Standard Model. In these proceedings, an overview of the most important CMS results from proton-proton data as of May 2014 will be given.
Discharge conditions in Hall thrusters: secondary electrons emission yield and magnetic mirror influence
J. Miedzik, D. Daniłko
One dimensional model of plasma bound by two nonconducting walls in external magnetic and electric field is developed. In particular it is designed to describe plasma in Hall thrusters. Combination of Particle-in-cell method with guiding centre approximation of electrons motion allows for kinetic description in short computational time. Comparison of plasma parameters done for two different secondary electrons emission profiles reveals insignificant influence of wall material on the condition in one dimensional model.
Fast data transmission in dynamic data acquisition system for plasma diagnostics
This paper describes architecture of a new data acquisition system (DAQ) targeted mainly at plasma diagnostic experiments. Modular architecture, in combination with selected hardware components, allows for straightforward reconfiguration of the whole system, both offline and online. Main emphasis will be put into the implementation of data transmission subsystem in said system. One of the biggest advantages of described system is modular architecture with well defined boundaries between main components: analog frontend (AFE), digital backplane and acquisition/control software. Usage of a FPGA chips allows for a high flexibility in design of analog frontends, including ADC ↔ FPGA interface. Data transmission between backplane boards and user software was accomplished with the use of industry-standard PCI Express (PCIe) technology. PCIe implementation includes both FPGA firmware and Linux device driver. High flexibility of PCIe connections was accomplished due to use of configurable PCIe switch. Whenever it's possible, described DAQ system tries to make use of standard off-the-shelf (OTF) components, including typical x86 CPU & motherboard (acting as PCIe controller) and cabling.
Computational Intelligence
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The concept of a flexible system for use in software engineering
Marek Adamek, Jan Mulawka
This paper concerns one of the fundamental issues of software engineering. We consider the concept of software metrics based on attributes describing each line of a computer program source code. Furthermore we present a design for a flexible, plugin based system which allows to define and use such metrics. To show the practical utility of the solution we implemented a basic version of the system and conducted experimental verification. Some of tests results and final conclusions are also provided.
Descriptor positive discrete-time and continuous-time nonlinear systems
Tadeusz Kaczorek
The positivity of discrete-time and continuous-time nonlinear systems is addressed. Necessary and sufficient conditions for the positivity of the descriptor nonlinear systems are established. A procedure for checking the positivity is proposed and demonstrated on numerical examples.
Fast learning method for RAAM based on sensitivity analysis
This article presents a novel combination of the Recursive Auto-Associative Memory model with the Sensitivity- Based Linear Learning Method. Training results on the syntactic trees dataset are presented, confirming that the application of the SBLLM method to the RAAM model results in very fast learning and yields clustering results of the same quality as the original RAAM model.
Fast Huffman encoding algorithms in MPEG-4 advanced audio coding
This paper addresses the optimisation problem of Huffman encoding in MPEG-4 Advanced Audio Coding stan- dard. At first, the Huffman encoding problem and the need of encoding two side info parameters scale factor and Huffman codebook are presented. Next, Two Loop Search, Maximum Noise Mask Ratio and Trellis Based algorithms of bit allocation are briefly described. Further, Huffman encoding optimisation are shown. New methods try to check and change scale factor bands as little as possible to estimate bitrate cost or its change. Finally, the complexity of old and new methods is calculated, compared and measured time of encoding is given.
Optimization of semi-global stereo matching for hardware module implementation
Mikołaj Roszkowski
Stereo vision is one of the most intensively studied areas in the field of computer vision. It allows the creation of a 3D model of a scene given two images of the scene taken with optical cameras. Although the number of stereo algorithms keeps increasing, not many are suitable candidates for hardware implementations that could guarantee real-time processing in embedded systems. One of such algorithms is semi-global matching, which seems to balance well the quality of the disparity map and computational complexity. However, it still has quite high memory requirements, which can be a problem if the low-cost FPGAs are to be used. This is because they often suffer from a low external DRAM memory throughput. In this article, a few methods to reduce both the semi-global matching algorithm complexity and memory usage, and thus required bandwidth, are proposed. First of all, it is shown that a simple pyramid matching scheme can be used to efficiently reduce the number of disparities checked per pixel. Secondly, a method of dividing the image into independent blocks is proposed, which allows the reduction of the amount of memories required by the algorithm. Finally the exact requirements for the bandwidth and the size of the on-chip memories are given.
Hardware-oriented simplifications of the prediction algorithms in the H.265/HEVC encoder
Maciej Trochimiuk, Andrzej Abramowski
This paper presents a hardware-oriented analysis of the mode decision algorithms for intra and inter prediction in the H.265/HEVC encoder. A number of simplifications, aimed to achieve real-time encoding of high-resolution video sequences in the hardware implementation, is proposed. The potential acceleration of the encoding is associated with losses in the encoding efficiency. Therefore, the trade-off between encoding speed and quality is inspected closely.
Analysis and comparison of NoSQL databases with an introduction to consistent references in big data storage systems
Adam Dziedzic, Jan Mulawka
NoSQL is a new approach to data storage and manipulation. The aim of this paper is to gain more insight into NoSQL databases, as we are still in the early stages of understanding when to use them and how to use them in an appropriate way. In this submission descriptions of selected NoSQL databases are presented. Each of the databases is analysed with primary focus on its data model, data access, architecture and practical usage in real applications. Furthemore, the NoSQL databases are compared in fields of data references. The relational databases offer foreign keys, whereas NoSQL databases provide us with limited references. An intermediate model between graph theory and relational algebra which can address the problem should be created. Finally, the proposal of a new approach to the problem of inconsistent references in Big Data storage systems is introduced.
Online 3D face reconstruction with incremental Structure From Motion and a regressor cascade
Marek Kowalski, Władysław Skarbek
In this paper we present a method for online 3D face reconstruction from a video sequence. The face landmarks in a given frame are detected and used to create a 3D shape estimate. The resulting 3D shape is an approximate, sparse representation of the subject’s face. Our reconstruction step is based on a revised version of incremental Structure From Motion, where we use a novel 4D subspace tracking procedure followed by scaled deflation against a vector of ones. Facial landmark detection is built upon a regressor cascade scheme where each subsequent regressor updates the initial shape obtained from the preceding frame.
A computer method of finding valuations forcing validity of LC formulae
Łukasz Godlewski, Kordula Świętorzecka, Jan Mulawka
The purpose of this paper is to present the computer implementation of a system known as LC temporal logic [1]. Firstly, to become familiar with some theoretical issues, a short introduction to this logic is discussed. The algorithms allowing a deep analysis of the formulae of LC logic are considered. In particular we discuss how to determine if a formula is a tautology, contrtautology or it is satisfable. Next, we show how to find all valuations to satisfy the formula. Finally, we consider finding histories generated by the formula and transforming these histories into the state machine. Moreover, a description of the experiments that verify the implementation are briefly presented.
Combined P-type frames bitrate estimation
Michał Wieczorek
In this paper, a novel rate control algorithm for video sequences with inter-frame prediction is presented. The proposed approach exploits dependencies between bit rates of successive frames of both header and coefficient data and simplifies the rate control process by excluding complex multiplications. It is an important goal as recent rate control algorithms are quite complex and their implementations, particularly in hardware structures, can be inconvenient.
Analysis of selected methods for the recovery of encrypted WEP key
This paper deals with some of the WEP (Wired Equivalent Privacy) key decryption methods based on aircrack-ng software, which was embedded in Backtrack operating system (Linux distribution). The 64-bit (40-bit) and 128-bit (104- bit) key encrypted with RC4 cipher weakness was shown. Research methods were made in different network environments. In this work we compared different types of keys to check how strong the RC4 stream cipher can be. The 40-bit and 104-bit WEP key has been tested on IEEE 802.11 based wireless LAN using laptop with live-CD Linux operating system. A short analysis of key creation methods was performed to compare the amount of time necessary to decrypt random and nonrandom WEP keys.
3D reconstruction software comparison for short sequences
Adam Strupczewski, Błażej Czupryński
Large scale multiview reconstruction is recently a very popular area of research. There are many open source tools that can be downloaded and run on a personal computer. However, there are few, if any, comparisons between all the available software in terms of accuracy on small datasets that a single user can create. The typical datasets for testing of the software are archeological sites or cities, comprising thousands of images. This paper presents a comparison of currently available open source multiview reconstruction software for small datasets. It also compares the open source solutions with a simple structure from motion pipeline developed by the authors from scratch with the use of OpenCV and Eigen libraries.
Electronic Systems
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Development of the unmanned aerial vehicle flight recorder
Wojciech Walendziuk, Daniel Kwasniewski
This work presents a telemetric flight recorder which can be used in unmanned aerial vehicles. The device can store GPS position and altitude, measured with the use of pressure sensor HP03M, a flying platform. The most important subassembly of the recorder is an M2M family device H24 modem developed by Telit company. The modem interface communicates with the use of UART interface and AT commands. The autonomic work is provided by a microcontroller which is master component of the recorder. The ATmega 664P-AU from AVR family microcontrollers developed by Atmel is used. The functionality of the measurement system was developed in such a way that a GSM module can send current position to the base station on demand. In the paper the general description of the device and achieved results of tests are presented.
An algorithm for a lossless compression of raw radar data
Bartosz Pikacz
This paper presents a novel algorithm designed and optimized for a lossless, real-time compression of raw data in pulse radar system. Characteristics of radar data are described together with compression methods exploiting them. Compression ratios of presented algorithm are measured for multiple data sets recorded by different types of radar and in different working conditions. The results are compared with compression ratios of conventional compression algorithms and with the theoretical limits determined by the Shannon entropy.
Lumped circuit model of RF amplifier for SPICE simulator
Katarzyna Opalska
The paper presents the lumped model of RF amplifier for the generic SPICE circuit simulator. Model is constructed on the basis of measured s-parameter data set of the amplifier. Data – transformed to admittance (y) domain - is approximated by rational functions, which later are synthesized as RLC (sub)circuits. Final amplifier model - obtained by representing Y matrix of two-port circuit by the set of passive components and controlled voltage/current sources – is shown to be equivalent to the original s-based model and may be used in any generic circuit simulator.
Modeling of a 3DTV service in the software-defined networking architecture
In this article a newly developed concept towards modeling of a multimedia service offering stereoscopic motion imagery is presented. Proposed model is based on the approach of utilization of Software-defined Networking or Software Defined Networks architecture (SDN). The definition of 3D television service spanning SDN concept is identified, exposing basic characteristic of a 3DTV service in a modern networking organization layout. Furthermore, exemplary functionalities of the proposed 3DTV model are depicted. It is indicated that modeling of a 3DTV service in the Software-defined Networking architecture leads to multiplicity of improvements, especially towards flexibility of a service supporting heterogeneity of end user devices.
Variability-based global sensitivity analysis of circuit response
The research problem of interest to this paper is: how to determine efficiently and objectively the most and the least influential parameters of a multimodule electronic system - given the system model f and the module parameter variation ranges. The author investigates if existing generic global sensitivity methods are applicable for electronic circuit design, even if they were developed (and successfully applied) in quite distant engineering areas. A photodiode detector analog front-end system response time is used to reveal capability of the selected global sensitivity approaches under study.
Macrosimulation of nonlinear dynamic systems for wave-shaping applications
Jan Ogrodzki, Piotr Bieńkowski
Macromodeling is a technique widely used in circuits simulation. Macromodels usually describe complex, repetitive parts of large systems. They are often created on the base of original circuits by their simplification, e.g. macromodels of operational amplifiers. Another group of macromodels makes use of the circuit response approximation. This approach is called behavioral macromodeling. Low numerical complexity of behavioral macromodels is especially useful in CAD systems where circuit simulation must be run many times. In this paper the behavioral macromodeling technique has been applied to the whole circuit not to its part. This technique may be understood as shaping of the circuit output response and so belongs to a class of wave-shaping methods. We have used it to nonlinear, dynamic circuits with periodic signals of finite spectra, as e.g. in audio systems. The macromodels shape their frequency and spectral characteristics with a sufficient simplicity to omit unwanted distortions and with a sufficient efficiency to run the simulator in real time. Elaboration of this wave-shaping simulator is based on dynamic circuits identification, Fourier approximation of signals and harmonic balance technique. The obtained macromodel can be run as a software substitute for a hardware audio system.
Geant4 simulations of detector response matrix for Caliste-SO
J. Barylak, P. Podgórski, T. Mrozek, et al.
The paper presents a method for determining the Detector Response Matrix (DRM) using Monte Carlo simulations. For this purpose Geant4 package was used which enables simulations of the interaction of particles with matter. The DRM has been calculated for cadmium telluride sensor of Caliste-SO detector, which will be used in the Solar Orbiter/STIX instrument. Solar Orbiter is the M-class mission of the new ESA’s program Cosmic Vision 2015-2025. It is to be launched in July 2017. STIX will provide imaging spectroscopy of solar hard X-ray emissions from 4 keV to 150 keV using a Fourier-imaging technique. Long operation of detectors under space condition raises a need for development of dedicated tools for analysis of behaviour of the detectors in changing/harsh radiation environment and its impact on detector quantum efficiency due to aging effects. Obtained results exhibit a high usefulness of Geant4 package in this kind of analysis.
Solar Orbiter spacecraft instrument interface simulator and its applications for the STIX telescope tests
Solar Orbiter mission of European Space Agency, scheduled for launch in 2017, is designed to explore the Sun and the inner heliosphere. Its close, never achieved before by any other spacecraft, approach to the Sun as well as ten remote-sensing and in-situ on board instruments will allow obtaining unique solar science data. The Spectrometer Telescope for Imaging X-rays (STIX) is one of them. Its measurements of solar thermal and non-thermal hard X-ray emissions from ~4 to 150 keV will play an important role to achieve mission's major science goals. The Spacecraft Instrument Interface Simulator (SIIS) is specified as a part of Electrical Ground Support Equipment with the aim to provide a tool for power interface and telemetry/telecommand electrical and data protocol validation during the delivery phase of STIX instrument for spacecraft integration. It is designed to be used during the instrument development and test phases of onboard algorithms, too. Brief overview of SIIS use and performance for these purposes is given in this work.
Power transformer testing
Magdalena Zagrobelna, Andrzej Wasilewski
This paper presents the method of oil-filled transformer monitoring by means of a fiber optic sensor. Our method can be extremely useful in case of prevent overheating and the winding failure. A special semiconductor technology plays an important role in such measurement. The tests were carried out by means of the developed test stand imitating a real power transformer.
Python based high-level synthesis compiler
Radosław Cieszewski, Krzysztof Pozniak, Ryszard Romaniuk
This paper presents a python based High-Level synthesis (HLS) compiler. The compiler interprets an algorithmic description of a desired behavior written in Python and map it to VHDL. FPGA combines many benefits of both software and ASIC implementations. Like software, the mapped circuit is flexible, and can be reconfigured over the lifetime of the system. FPGAs therefore have the potential to achieve far greater performance than software as a result of bypassing the fetch-decode-execute operations of traditional processors, and possibly exploiting a greater level of parallelism. Creating parallel programs implemented in FPGAs is not trivial. This article describes design, implementation and first results of created Python based compiler.
Improvement of pipeline ADC resolution in sequential stages of conversion
Ł. Małkiewicz
Due to high discrepancy between possible combinations of rate and resolution of today’s analog to digital converters (ADCs) and capabilities of the digital systems in favour of the latter, improvement of ADCs performance still is and will likely long be an actual issue. A perspective class of converters that allows further improvements of conversion quality, are adaptive pipeline ADCs (APADCs). APADCs on top of having all of the virtues of pipeline ADCs, such as an excellent compromise of relatively high speed due to pipelining of conversion iterations and high accuracy, as well as relatively low complexity, sizes and power consumption, thanks to computing of codes of input samples using digital signal processing (DSP) algorithms, allow full optimization of their functioning and achievement of better performance than of conventional pipeline ADCs. Optimization of APADC requires identification of factors critically influencing performance of APADC. This work focuses on one of them - the difference between resolution of estimates computed by a given stage of APADC and resolution of feedback DACs in following stages producing their analog equivalents, which creates a need for estimates resolution reduction in the course of conversion. The influence of the latter on work and performance of APADC is analyzed in the paper and a method to compensate this influence and improve resolution of APADC in sequential stages of conversion, is developed. Results of simulation experiments that prove effectiveness of the proposed solution and allow to estimate the benefits resulting from it, are presented.
Robust constant modulus algorithms for channel equalization
Z. Gajo, M. Linczuk
In this paper a robust version of conventional constant modulus algorithm is presented. This robust algorithm is used for multipath channel equalization in the presence of impulsive heavy-tailed noise described by ߙ-stable distribution. The advantage of presented robust algorithm over conventional algorithm dedicated to Gaussian noise is confirmed experimentally.
Research on impact of the environmental factors on National Institute of Telecommunications time standards stability
M. Marszalec, Marzenna Lusawa
National Institute of Telecommunications (NIT) has been operating time standards from over 15 years. They are part of worldwide and national time comparison system and are used in calculations of international and polish timescales, International Atomic Time Scale (TAI), Universal Time Coordinated (UTC), Polish Atomic Time Scale (TA(PL)) and Polish Official Time (UTC(PL)). This year the standards has been moved to new Time Standards Chamber which is precisely air conditioned and power secured. This article presents some interesting considerations on impact of the environmental factors on time standards stability.
Soft-output demapper and Viterbi decoder for software-defined radio
Marcin Darmetko
Viterbi algorithm is commonly used in communication systems to decode convolutional codes. Soft decision demapping can be used to further improve Viterbi decoder performance. This paper presents implementation of soft-decision demapping and Viterbi decoder for software-defined radio (SDR). Fast simplified algorithms for soft demapping of four modulations common in satellite communications systems (BPSK, QPSK, 8-PSKand 16-APSK) were implemented. To increase software processing speed SIMD (single instruction multiple data) instructions were used.
General principles and stages of optimal AFCS design
A. Platonov, Ie. Zaitsev
The goal of the paper is a discussion of general principle and stages of the optimal analog feedback communication systems (AFCS) design. Previous research devoted to the analysis of particularities of AFCS functioning gave necessary analytical basis for transition to practical design of optimal AFCS. This is new class of communication systems (CS) transmitting the signals, under given bit error rate (BER), with bit rate equal to the capacity of the forward channel and power-bandwidth efficiency attaining the theoretical limit. In the paper, we describe the ordered sequence of the stages of transition from the abstract results to designing of the pre-commercial versions of optimal AFCS considering them as the basic communication link “sensor node (SN)” - “base station” (BS) of the wireless sensor network (WSN). We also show that verified theoretical results enable analytically argued decision making at different stages of designing of the high quality and energy efficient WSN communication links. This facilitates optimisation of the project works schedule, distribution of the tasks and resources for their realization, reduce the time and cost of design.
Overview of electric propulsion
Dariusz Daniłko
Space Electric Rocket Test (SERT 1) was the first experiment in which electric propulsion device was sent into space. The present year marks the 50th anniversary of that particular mission that opened the door for the application of electric propulsion on board spacecrafts. We present an overview of existing electric propulsion technology along with the description of the most successful missions that followed the success of the SERT 1mission.
The research of the solar panels-commutator-inverter-load system with the pulse-amplitude control
K. N. Taissariyeva, N. T. Issembergenov
The system "solar panels-commutator-inverter-load" with amplitude-impulse control was researched. It was shown that if the solar panels are located in a certain way at the input of the inverter, it will be possible to get multilevel voltage close to sine wave with the help of amplitude-impulse control of commutator at the output of inverter. Herewith the effect is saving of solar panels depending on the quantity of voltage level, and also the enhanced voltage distortion coefficient (THD). For instance, with 8-level of voltage 28,2% and THD=4,64%, with 13-level of voltage, 30,5% and THD=2,65%, and with 26-level of voltage 31,7% and THD=1,22%. The given results were obtained through computer modeling and experimental research.
Evolution of architectures and conversion algorithms in adaptive sub-ranging A/D converters
The paper presents the survey of architectures and conversion algorithms used in so called adaptive analog-to-digital converters considered during the studies on these converters carried out by the author and his colleagues. The key idea that distinguishes the adaptive analog-to-digital converters from other sub-ranging converters consists in application of the iterative digital signal processing algorithm for calculation of the output codes of the converters and for calculation of the values of residue signal gains in subsequent steps of conversion. Application of this approach in the proposed converters allows to achieve better parameters of the converters in comparison with parameters of conventional sub-ranging analog-to-digital converters.