This PDF file contains the front matter associated with SPIE Proceedings Volume 9662, including the Title Page, Copyright information, Table of Contents, Introduction, and Conference Committee listing.

Wilga Summer 2015 Symposium on Photonics Applications and Web Engineering was held on 23-31 May. The Symposium gathered over 350 participants, mainly young researchers active in optics, optoelectronics, photonics, electronics technologies and applications. There were presented around 300 presentations in a few main topical tracks including: bio-photonics, optical sensory networks, photonics-electronics-mechatronics co-design and integration, large functional system design and maintenance, Internet of Thins, and other. The paper is an introduction the 2015 WILGA Summer Symposium Proceedings, and digests some of the Symposium chosen key presentations.

XXXVth periodic Symposium WILGA (winter edition) on Design, Construction and Application of Advanced Electronic and Photonic Systems was held at the end of January 2015. It is an established, periodic meeting of young researchers, M.Sc. and Ph.D. students and their supervisors. The meeting is organized by the PERG/ELHEP Laboratories of Institute of Electronic Systems - WUT since two decades. Sessions of the 2015 January meeting were: development of the architecture of digital electronics, embedded systems, design of system functionality, analog electronics and photonics, hardware – software integration, complex system reliability and dependability working in harsh environments, applications of electronic and photonic systems in space and satellite engineering and large research experiments. Summer edition of WILGA Symposium is organized on 25-31 May 2015 [wilga.ise.pw.edu.pl].

The paper analyzes suitability of various spectrally efficient modulations (PAM, CAP, OFDM/DMT) in a VLC system using lighting LEDs as a transmitter. Although under ideal conditions all modulation have similar efficiency i.e. they produce similar throughputs with a given BER, their practical performances are different. For example, the level of nonlinear distortions generated by each modulation is the least for PAM and by far the greatest for OFDM/DMT locating CAP in the middle. The suitability of various OFDM/DMT variants in a VLC LED link was also analyzed proving that the asymmetrically clipped (ACO) OFDM has a worse performance as compared with DC biased (DCO) OFDM.

Continuous increasing share of light emitting diodes (LEDs) in a lighting market, which we observe during the last couple years, opens new possibilities. Especially, when we talk about practical realization the concept of visible light communications (VLC), which gains on popularity recently. The VLC concept presupposes utilization of illumination systems for a purpose of data transmission. It means, the emitters, in this case the LEDs, will not of a light source only, but also the data transmitters. Currently, most of the conducted researches in this area is concentrated on achievement of effective transmission methods. It means a transmission only in one direction. This is not enough, when we talk about the fully functional transmission system. Ensuring of feedback transmission channel is a necessary also. One of the ideas, which was postulated by authors of this article, is using for this purpose the LEDs in a double role. A utilization of LEDs as photo-detectors requires a reverse polarization, in contrast to a forward bias, which has a place when they work as light emitters. Ensuring of proper polarization get significant meaning. The article presents the investigations results on the influence of reverse bias on photo-receiving properties of LEDs used as light detectors. The conducted research proved that an improvement of sensitivity and bandwidth parameters are possible by application of appropriate value of the reverse voltage in a receiver.

The paper presentes a two way open space optical link ready for 10/100 Mbit/s Ethernet signal transmission. It uses lighting LEDs as light sources in both transmission directions. A detailed description of used circuitry is given together with preliminary results.

Existing optical networks are driven by dynamic user and application demands but operate statically at their maximum performance. Thus, optical links do not offer much adaptability and are not very energy-efficient. In this paper a novel approach of implementing performance and power adaptivity from system down to optical device, electrical circuit and transistor level is proposed. Depending on the actual data load, the number of activated link paths and individual device parameters like bandwidth, clock rate, modulation format and gain are adapted to enable lowering the components supply power. This enables flexible energy-efficient optical transmission links which pave the way for massive reductions of CO2 emission and operating costs in data center and high performance computing applications. Within the FP7 research project Adaptive Data and Power Aware Transceivers for Optical Communications (ADDAPT) dynamic high-speed energy-efficient transceiver subsystems are developed for short-range optical interconnects taking up new adaptive technologies and methods. The research of eight partners from industry, research and education spanning seven European countries includes the investigation of several adaptive control types and algorithms, the development of a full transceiver system, the design and fabrication of optical components and integrated circuits as well as the development of high-speed, low loss packaging solutions. This paper describes and discusses the idea of ADDAPT and provides an overview about the latest research results in this field.

This paper discusses the challenges and the trade-offs in the design of laser drivers for very-short distance optical communications. A prototype integrated circuit is designed and fabricated in 28 nm super-low-power CMOS technology. The power consumption of the transmitter is 17.2 mW excluding the VCSEL that in our test has a DC power consumption of 10 mW. The active area of the driver is only 0.0045 mm². The driver can achieve an error-free (BER < 10 ^-12) electrical data-rate of 25 Gbit/s using a pseudo random bit sequence of 2⁷ -1. When the driver is connected to the VCSEL module an open optical eye is reported at 15 Gbit/s. In the tested bias point the VCSEL module has a measured bandwidth of 10.7 GHz.

Multiparametric capillary sensors are used for examination of liquids. The measurements results from such sensors are data from time series measurements taken during the movement of the fluid inside the capillary. The truthful characterization requires simultaneous measurements at different capillary points or performed with different techniques or specification. Points and tracks of time series can be analyzed simultaneously. Such analysis performed by trained human operators is time consuming and sometimes not precise because of slow signals levels variations resulting from device imperfection, and fast variations resulting from the presence of noise. The paper presents result of software characteristic data detection from a two-channel capillary sensor. One channel is for the reflected signal measurement; the other channel is for sensing of the scattered signal. The fluid movement inside the capillary is forced by local heating. The software analysis allows the classification of diesel and biodiesel fuel by their content on the base of the slopes of signals manifestation. Obtained results show that the automated analysis of the differences between two simultaneous channels of signals provides more precise data than those obtained from independent time series analysis.

In this paper the analysis of the transmission quality in Nyquist WDM transport system is presented. Results are presented of a system simulation carried out for different modulation format, symbol rates, channel spacing and filter characteristics of the transmitter and receiver. This paper also contains the comparison between results obtained for the N-WDM (Nyquist Wavelength Division Multiplexing) and DWDM (Dense Wavelength Division Multiplexing) system. Two quality indicators are taken into consideration: interchannel crosstalk and symbol error rate for both different system configurations.

An optoelectronic system for measurements of hematocrit level (HCT) in the whole human blood is presented. Proposed system integrates a dedicated optoelectronic sensor, a microcontroller and a small LCD display in a low cost, battery-powered, handheld device. Chosen method for determining blood hematocrit level is based on optical properties of whole blood in visible and NIR wavelength range. Measurements with the use of proposed system require blood samples (small drop in the range of microliters) which is placed in the micro cuvette. Then, absorption of the sample is measured at wavelengths of 570 nm and 880 nm. Prototype of the device was build and tested. Test results confirmed proper operation of the device with correct metrological parameters in application to HCT level measurements. Such a portable device can be used as a tool of bedside diagnosis, which becomes interesting alternative to full laboratory tests.

Mathematical model of distributed temperature sensor based on spontaneous Raman scattering is described in this paper. The concept uses Stokes and anti-Stokes scattered signals as reference and detection signals respectively. Model is completed by experimental results coming from setup of 200 m G.652 sensing fiber tested in temperatures 3°C, 15°C, 23 °C and 30°C and 2500 m reference fiber preserved in 22°C. Parameters of the scattered signal source in used setup configuration allow to achieve distributed temperature profile with spatial resolution up to 50 m.

In the article the multimode tapered optical light pipe for illumination systems was investigated. Based on tree light emitting diodes at the wavelength of 460 nm (blue), 528 nm (green) and 631 nm (red) possibility of white light emission on the output surface of the tapered light pipe was submitted. Influence of optical power of LEDs on the colour coordinates (CIE-1931) has been investigated.

Local liquid sample heating is used in multiparametric sensors of liquid type classification and in sensors of liquid flow. In such applications, the heating of the liquid is done by micro-heaters, with the liquid separated from the micro-heater. The presented paper concentrates on the physical conditions of liquid sample heating used in capillary sensors. In such devices the repeatable transfer of heat is required. The basic measurements include time of liquid to vapor phase transitions and local transfer of heat. In the work were used experimental and simulation techniques. The obtained results show that in the capillary sensor repeatable local heat transfer conditions can be easier achieved than repeatable time of liquid to vapor phase transitions. In the analyzed case, the local heating depends mostly on the capillary to micro-heater distance. The liquid to vapor transition times, beside of the liquid type, depend on the powers used for micro-heater heating and on capillary cross-section parameters, such as the inner and outer diameter values. By increasing the power to the micro-heater the transition time variability is reduced.

In the paper we present a successful joint transmission of the IEEE 802.11 signal and an optical Gbit Ethernet over a multimode fiber based link. Most importantly, the multiplexation of both signals was performed in the optical domain. Due to the utilization of the multimode fiber the OBI noise was avoided and both channels were able to operate at the same wavelength. We prove that potential RoF link for IEEE 802.11 signal distribution may be used to additionally transmit other signals as Gbit Ethernet and therefore utilize the fiber infrastructure installed more effectively. The qualities of both the IEEE 802.11 and Ethernet transmissions fulfilled the requirements imposed by appropriate standards.

The realization of a laboratory stand for testing photovoltaic panels is presented here. The project of the laboratory stand was designed in SolidWorks software. The aim of the project was to control the electrical parameters of a PV panel. For this purpose a meter that measures electrical parameters i.e. voltage, current and power, was realized. The meter was created with the use of LabJack DAQ device and LabVIEW software. The presented results of measurements were obtained in different conditions (variable distance from the source of light, variable tilt angle of the panel). Current voltage characteristics of photovoltaic panel were created and all parameters could be detected in different conditions. The standard uncertainties of sample voltage, current, power measurements were calculated. The paper also gives basic information about power characteristics and efficiency of a solar cell.

In this paper the off-grid photovoltaic system consisting of a PV panel, MMPT charge controller and battery is described. The realization of a laboratory stand for charging or discharging batteries is presented. Original monitoring and control system, which is based on LabVIEW software and LabJack DAQ device, has been built. Data acquisition part, arithmetic part and front panel of program created in LabVIEW are described. Some problems with implementation of this system, providing the monitoring of electrical parameters, are mentioned.

In this article a laboratory stand for measuring the impact of temperature on the electrical parameters of a photovoltaic panel is presented. For this purpose, the original program in LabVIEW for temperature, electric current and voltage acquisition in real time had to be created. Data acquisition was done automatically. On the basis of the results, the current-voltage characteristics were created. Moreover, the temperature coefficients and efficiency of a photovoltaic panel were calculated. The parameter values of a polycrystalline photovoltaic panel decreased with the rise of temperature. The short-circuit current, which increased slightly, was the exception. With the temperature increase, the efficiency of the tested panel decreased by approximately 0.5% per Kelvin.

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 support vector machine to classify flame image which correspond with the state of the combustion process.

During the past years significantly increased the number of LED models available on the market. However, not all of them have parameters which allow for use in professional lighting systems. The article discusses the international standards which should be met by modern LEDs. Among them, one of the most important parameters is factor of luminous flux decline in value during the operation of the LEDs. Its value is influenced by many factors, among others, the junction temperature of the diode and average and maximum values of supply current. Other important, for lighting reasons, parameters are stability of correlated color temperature and stability of chromaticity coordinates of the emitted light. The paper presents a system to measure luminous flux and colorimetric parameters of LEDs. Measurement system also allows for measuring a change in these parameters during operation of the LED.

When testing transparent plates with high quality flat surfaces and a small angle between them the three-beam interference phenomenon is observed. Since the reference beam and the object beams reflected from both the front and back surface of a sample are detected, the recorded intensity distribution may be regarded as a sum of three fringe patterns. Images of that type cannot be succesfully analyzed with standard interferogram analysis methods. They contain, however, useful information on the tested plate surface flatness and its optical thickness variations. Several methods were elaborated to decode the plate parameters. Our technique represents a competitive solution which allows for retrieval of phase components of the three-beam interferogram. It requires recording two images: a three-beam interferogram and the two-beam one with the reference beam blocked. Mutually subtracting these images leads to the intensity distribution which, under some assumptions, provides access to the two component fringe sets which encode surfaces flatness. At various stages of processing we take advantage of nonlinear operations as well as single-frame interferogram analysis methods. Two-dimensional continuous wavelet transform (2D CWT) is used to separate a particular fringe family from the overall interferogram intensity distribution as well as to estimate the phase distribution from a pattern. We distinguish two processing paths depending on the relative density of fringe sets which is connected with geometry of a sample and optical setup. The proposed method is tested on simulated data.

In this paper, bismuth-germanate oxide glass doped with erbium ions has been synthesized. Composition of the glass has been chosen in terms of the low phonon energy and good transparency in the infrared region. Transparent glass-ceramics sample has been prepared by controlled crystallization process. Fourier transform infrared spectroscopy (FTIR) has been used to determinate structural properties of samples. The absorption coefficient, the luminescence intensity in visible and infrared region and the differential scanning calorimetry have been examined. Difference in the emission intensity and shape of the luminescence bands indicates the presence of crystalline phases in obtained glass-ceramics sample.

In the paper spectroscopic properties of aluminosilicate glasses co-doped with Nd³⁺/Yb³⁺ were investigated. Strong and wide emission in the 1μm region obtained by optimization of Nd³⁺ → Yb³⁺ energy transfer corresponding to the superposition of optical transitions Nd³⁺:⁴F_3/2 → ⁴I_11/2 and Yb³⁺:²F_5/2 → ²F_7/2 (Yb³⁺) was observed. The construction of double-core, double-clad optical fiber with cores manufactured from the aluminosilicate glass (co-doped with 1^st core- 0.15Nd₂O₃, 2^nd core - 0.15Nd₂O₃/0.45Yb₂O₃ mol%) was developed. Comparative analysis of shape of luminescence (λ_p=808 nm) obtained in bulk glass (0.15Nd₂O₃/0.45Yb₂O₃) and ASE in double-core optical fiber clearly shows significant differences in luminescent properties. Mechanisms influencing differences in the shape of luminescence of fabricated glass and optical fiber were also discussed.

The growing demand for higher data rate transmissions in local and metropolitan area networks is main reason of developing effective and inexpensive transmission systems. In this paper, study about the possibility to realize 1310 nm tunable DWDM transmitter using commercially available low-cost DFB lasers is presented. Extensive DFB lasers characterization has been performed which led to establish relationships between laser current, operational temperature, emitted wavelength and power. An algorithm to find the laser settings for a desired wavelength grid has been proposed and tested. Generation of the 1310nm DWDM channels with frequency spacing between 120 and 240GHz has been demonstrated.

The utilization of multiple wavelength domains in one transmission system has become a significant trend in modern opto-telecommunications due to the growing demand for transmission capacity. To realize parallel 1550/1310 nm transmission, new 1310 nm amplification techniques are needed, such as the 1310 nm Raman amplifier. In the paper, we investigate the performance of three different configurations of the 1310 nm QD laser based Raman amplifier. In the polarization multiplexed co-propagating configuration we obtained a gain of 9 dB, while it was reduced to 8 dB in the bi-directional configuration. The highest gain was achieved in the polarization multiplexed counter-propagating configuration, with a gain of over 16 dB. The presented results open the way for the optimization of the 1310 nm Raman amplifier’s architecture and the enhanced utilization of Raman amplifiers in telecommunication systems.

This article considers multilevel transistor inverter for converting energy of solar panels into electroenergy. The output of multilevel transistor inverter produces the voltage of almost sinusoidal form. The primary objective of this inverter is to transform solar energy into electroenergy of industrial frequency. The analysis of received output curves of voltage for sinusoidality has been conducted.

Lanthanum fluoride nanoparticles doped with Nd³⁺ ions obtained via solvothermal method have been presented. Doped nanoparticles were prepared in two-step method. Firstly rare-earth chlorides were synthesized from oxides and then they were used to prepare LaF₃ particles. The luminescence spectra shows typical for crystalline materials Stark splitting at 880 nm corresponding ⁴F_3/2 to ₄I_9/2 level transition and 1060 nm matching ⁴F_3/2 to ⁴I_11/2 level transition. The highest luminescence intensity was achieved for sample doped with 0.75% wt. of Nd³⁺, and the longest decay time for sample doped with 0.5% wt. which reached 328 μs. The XRD pattern analysis confirmed that obtained material consists of crystalline LaF₃, the grain size was estimated from Sherrer's formula and equaled about 25nm.

Color imaging depends strongly on the illumination conditions. Semi-specular surfaces impose ambiguity in colorimetric analysis and the specular reflection component has to be treated differently depending on the material. To exclude the specular component, special configuration of photometric devices is required. Such conditions cannot easily be met for images of irregular surfaces. I propose a simple method of structured light illumination for separating the specular and diffuse components of semi-specular surfaces using color camera and a calibrated flat-screen monitor.

High order modulation of 850nm bare Vertical Cavity Surface Emitting Lasers (VCSELs) has been studied. In particular, four-level pulse amplitude modulation (PAM-4) has been investigated in order to reach data transmission rates up to 25 GBaud. A probe station has been designed and built as a part of the bare VCSELs high speed test bed and static characterization bench. The PAM-4 quality evaluation methods have been developed.

Technology, characterization and in particularly modeling of 4H-SiC photodiode have been presented in this paper. Modeling and simulation has been performed using PSPICE environment. Comparison of simulation with real results for electrical characteristic (I-V) of circular SiC photodiodes has been also presented.

Actinometric station is using for measuring solar of radiation. The results are helpful in determining the optimal position of solar panels relative to the Sun, especially in today’s world, when the energy coming from the Sun and other alternative sources of energy become more and more popular. Polish climate does not provide as much energy as in countries in southern Europe, but it is possible to increase the amount of energy produced by appropriate arrangement of photovoltaic panels. There is the possibility of forecasting the amount of produced energy, the cost-effectiveness and profitability of photovoltaic installations. This implies considerable development opportunities for domestic photovoltaic power plants. This article presents description of actinometric system for diffuse radiation measurement, which is equipped with pyranometer - thermopile temperature sensor, amplifier AD620, AD Converter ADS1110, microcontroller Atmega 16, SD card, GPS module and LCD screen.

Fiberscopes are composed of an ordered optical fiber bundle. This construction allows faithful transmission of the luminance distribution of the frontal area to the end of fiberscope-image. This paper presents method to obtain the transfer effect of the luminance distribution in unordered fiber bundle. Large number of fibers in a bundle results in the possibility of obtaining high-resolution. This article shows the possibility of obtaining the function of a typical fiberscope in a disordered bundle of fibers.

In the paper thermal and luminescence properties of phospho-tellurite glass and glass after thermal treatment doped with NdF₃ were presented. The crystallization kinetic of the main crystallization peaks of glass was investigated using differential scanning calorimetry (DSC). The value of the activation energy for crystalline phase (E_c 54,21 ± 5 kJ mol^-1) was calculated using Ozawa-Flynn-Wall (OFW), Kissinger-Akahira-Sunose (KAS), Starink and Tang methods. The glass-ceramic was obtained by heat treatment method. The luminescence transitions from levels ⁴F_5/2 → ⁴I_9/2 (878 nm), ⁴F_3/2→⁴I_11/2 (1058 nm), and ⁴F_3/2 → ⁴I_13/2 (1330 nm) in glass and glass-ceramic doped NdF3 were compered.

The paper presents new construction of luminescent photonic sensor based on an optical fiber capillary with a side ribbon doped with Sm³⁺ ions. Samarium ions ensure efficient excitation at the wavelength of 405 nm and multi colour luminescence in visible spectrum (550-720 nm). This phenomenon was proposed to increase sensor accuracy by using measurements of certain wavelength. The luminescence and angular characteristics of developed optrode were characterized at the lateral and face excitation of special capillary fibre construction. Rhodamine B (RhB) was used as a test solution in designed optrode. The nearly linear characteristic of RhB concentration was obtained for up to 0.15 % (w/w). The results indicate that the designed optrode can be used for construction of compact luminescent sensor for measuring selected properties of the solutions.

The paper proposes a method to quantify inaccuracy of the DGD estimation in which the propagation model neglects nonlinearities in an optical fiber and presents the results of the assessment. The practical limits for the application of the linear model can be learnt. The outcome of the paper can be used as a source for design directions for in-work DGD monitoring systems for optical communications.

Spectrum reflected or transmitted by fiber Bragg grating (FBG) in laboratory environment usually has smooth shape with high signal to noise ratio, similar to Gaussian curve. However, in some applications reflected spectrum could included some strong noise, especially where sensing array contains large number of FBGs or while is used broadband, low power source. This paper presents a possibility for extraction fiber Bragg grating peak wavelength from spectra with weak signal to noise radio with most frequently using digital signal processing algorithms. The accuracy of function minimum, centroid and Gaussian fitting methods for peak wavelength detection is compared. The linearity of processing characteristics of extended FBG measured for reference high power and second, low power source is shown and compared.

We present studies over the relations between stellar mass, redshift and star formation history for a high quality sample of early-type galaxies (ETGs) observed by the by the VIMOS Public Extragalactic Redshift Survey (VIPERS). VIPERS is an ongoing Large Programme to map in detail the large-scale distribution of galaxies at 0:5 < z < 1:2 with a unique volume (24 deg²) and sampling rate (~= 45%). At this redshift, IPERS fills a unique niche in galaxy surveys, provides a exceptional opportunity to study galaxies and their evolution at an epoch when the Universe had approximately half its current age. VIPERS data set will become the z ~ 1 equivalent of current state-of-the-art local (z < 0:2) surveys, allowing us to compare measurements at these two different epochs on equal statistical footing. The final sample of this survey is going to reach nearly 100,000 galaxies. As the VIPERS sample contains ~ 15% of the early type galaxies with known spectroscopic redshift and a very good quality spectra, it is a perfect sample to study the star formation history based on their spectroscopic features. We show that there the age of stellar population is depending on the stellar mass and the redshift. Our results show that lower mass galaxies have young stellar populations, while higher mass ETGs are populated with old stars. This suggest that marginal star formation occurs in massive galaxies. This result is consistent with the observations of the local Universe. Moreover, this trend of evolution is preserved for the different redshift range between 0:4 < z < 1:2.

This article presents a laboratory stand used for research concerning static and dynamic characteristics of MAV (micro air vehicle) drive units. An electric powered drive unit, applied in unmanned flying vehicles of short range was chosen as the research object. Such device consists of the following elements: acquisition and control unit, a variable frequency drive (VFD), an engine and a propeller. The article contains a description of the stand structure as well as the way of data acquisition and an example of its processing in the post-processing mode. Moreover, example tests and the results are presented here.

Photovoltaic (PV) technology is an attractive source of power for systems without connection to power grid. Because of seasonal variations of solar radiation, design of such a power system requires careful analysis in order to provide required reliability. In this paper we present results of three-year measurements of experimental PV system located in Poland and based on polycrystalline silicon module. Irradiation values calculated from results of ground measurements have been compared with data from solar radiation databases employ calculations from of satellite observations. Good convergence level of both data sources has been shown, especially during summer. When satellite data from the same time period is available, yearly and monthly production of PV energy can be calculated with 2% and 5% accuracy, respectively. However, monthly production during winter seems to be overestimated, especially in January. Results of this work may be helpful in forecasting performance of similar PV systems in Central Europe and allow to make more precise forecasts of PV system performance than based only on tables with long time averaged values.

ChemiX is a new generation Bragg crystal spectrometer intended to measure X-ray spectra from solar corona. The instrument is under development, and will be attached as one of the scientific equipment to Russian space solar observatory Interhelioprobe. The final heliocentric orbit will be reached after cruise phase which involves exposing the observatory to varying thermal conditions during the whole mission. Final scientific orbit is highly eccentric which results in substantial changes of solar heat flux. The power dissipated inside the instrument itself has also significant impact on thermal conditions. Furthermore ChemiX, as a component of whole spacecraft, will receive and give back some heat due to conduction to the main structure.

Proper evaluation of temperatures and heat fluxes in this case is not only important for correct performance of ChemiX but also for success of whole Interhelioprobe mission. To evaluate those parameters a steady state analysis in satellite crucial position was provided as well as computer simulation.

The paper presents a two methods for simulation of signal induction in the detector. First method base on carriers tracks calculation while second method include simplification of accelerating calculations. Calculation has been performed for Caliste-SO detector, which is cadmium telluride X-ray detector. This detector will be used in the Solar Orbiter/STIX instrument. Solar Orbiter is M-class mission of the ESA's programme Cosmic Vision 2015-2025, which is conducted in collaboration with NASA. It will be launched in October 2018. STIX (Spectrometer/Telescope for Imaging X-Rays) is X-ray telescope and spectrometer and will observe solar X-ray emission from 4 to 150 keV using Fourier-imaging technique. Deep space condition can influence significantly the detector parameters. Tools for detectors behaviour analysis are needed to understand how this harsh radiation environment can influence detector quantum efficiency.

Obtaining interesting celestial objects from tens of thousands or even millions of recorded optical-ultraviolet spectra depends not only on the data quality but also on the accuracy of spectra decomposition. Additionally rapidly growing data volumes demands higher computing power and/or more efficient algorithms implementations. In this paper we speed up the process of substracting iron transitions and fitting Gaussian functions to emission peaks utilising C++ and OpenCL methods together with the NOSQL database. In this paper we implemented typical astronomical methods of detecting peaks in comparison to our previous hybrid methods implemented with CUDA.

"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 12^m-13^m range and time resolution of the order of 1 - 10 seconds. For now there are two working "Pi of the Sky" observatories: in San Pedro de Atacama (Chile) and near Mazagón in Southern Spain. In this paper we report on the status of the project, as well as recent observation of asteroid 2004BL₈₆, which passed the Earth in late January 2015, DG CVn outburst in 2014, satellites observations and our future plans.

The Pi of the Sky is a system of five autonomous detectors designed for continuous observation of the night sky, mainly looking for optical flashes of astrophysical origin, in particular for Gamma Ray Bursts (GRB). In the Pi of the Sky project we also study many kinds of variable stars (periods in range of 0.5^d - 1000.0^d) or take part in the multiwavelength observing campaigns, such as the DG Cvn outburst observations. Our wide field of view robotic telescopes are located in San Pedro the Atacama Observatory, Chile and INTA El Arenosillo Observatory, Spain and were designed for monitoring a large fraction of the sky with 12^m -13^m range and time resolution of the order of 1 - 10 seconds. During analysis of the variable stars observations very important is accurate determination of their variability parameters. We know a lot of algorithms which can be used to the variability analysis of the observed stars¹²³ . In this article using Monte Carlo analysis we compare all used by us the period detection algorithms dedicated to the astronomical origin data analysis. Based on the tests performed we show which algorithm gives us the best period detection quality and try to derived approximate formula describing the period detection error. We also give some examples of this calculation based on the observed by our detectors variable stars. At the end of this article we show how removing bad measurements from the analysed light curve affect to the accuracy of the period detection.

This paper describes study results regarding potential use of White Rabbit technology in Space Related Applications. During the study Technology Readiness Level and Compliance with Space Related Applications was evaluated. After considering possible deployment and development scenarios, main focus has been put on European Space Agency's tracking station system. This outcome derived from specific requirements of tracking system which are coherent with White Rabbit technology scope of application and further development plans. Current state of Time and Frequency Distribution technology implemented into tracking stations is based on multiple different technologies coexisting in parallel creating a complex system. It requires specific, custom made hardware to combine all the technologies which makes it expensive and difficult to maintain. White Rabbit could be use to reduce Time and Frequency Distribution to a single Ethernet based network with link redundancy, payload data transfer and sub-nanosecond accuracy.

This paper describes development of low noise readout subsystem for digital camera dedicated for astronomical observations. Main aim of the study is noise reduction in regard of sensor's output signal and noise added by the analogue electronics. Basic concept and simulation results of analogue front-end are presented. Various Digital Signal Processing schemes are considered in order to increase Signal to Noise ratio. Another step of development are design of the prototype PCB board and implementation of selected processing techniques in to the structure of a FPGA device.

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 12^m-13^m range and time resolution of the order of 1 - 100 seconds. LUIZA is a dedicated framework developed for efficient off-line processing of the Pi of the Sky data, implemented in C++.

The photometric algorithm based on ASAS photometry was implemented in LUIZA and compared with the algorithm based on the pixel cluster reconstruction and simple aperture photometry algorithm. Optimized photometry algorithms were then applied to the sample of test images, which were modified to include different patterns of variability of the stars (training sample). Different statistical estimators are considered for developing the general variable star identification algorithm. The algorithm will then be used to search for short-period variable stars in the real data.

Pi of the Sky is a system of wide field-of-view robotic telescopes designed for observations of short timescale astrophysical phenomena, especially for prompt optical GRB emission. The apparatus designed for autonomous operation follows the predefined observing strategy and adopts to the actual running conditions, monitoring a large part of the sky with time resolution of the order of 1 - 10 seconds and range 12^m-13^m. Observation strategy and system design was successfully tested with a prototype detector in Chile and starting 2013 the final Pi of the Sky detector system in operation at the INTA El Arenosillo Test Centre in Spain. For the analysis of the data from a wide field-of-view system a set of dedicated algorithms have been developed, which allowed us to reduce photometry uncertainty for bright stars to the level of 0.015^m– 0.02^m.

Design of the Pi of the Sky telescopes allows also for measurements of near-Earth objects as comets, asteroids, satellites and space debris. Precise determination of the orbit parameters of the geostationary satellites is possible when using a parallax measured with simultaneous observations from Spain and Chile. Dedicated tests have been performed recently to verify system capabilities for observation of objects on lower orbits, moving at higher speeds. First results are discussed in this contribution.

The presentation focuses on plans of the Pi of the Sky collaboration to participate in the future LSC-Virgo's Electromagnetic (EM) Follow-up campaigns. Pi of the Sky telescope participated in the first "EM Follow-up project", called Looc-Up^1-3 2009-2010 organized by LSC-Virgo collaboration. Pi of the Sky brought to the project an instrument with the biggest field of view and with a very high time resolution. Recently Pi of the Sky has signed an Memorandum of Understanding (MOU) with LSC-Virgo for EM Follow-up observations in the Advanced Detector Era (ADE). Plans of the Pi of the Sky telescope for joint observations with advanced LIGO and Virgo detectors will be also outlined.

Sports cycling is becoming increasingly popular over last years. Obtaining and maintaining a proper position on the bike has been shown to be crucial for performance, comfort and injury avoidance. Various techniques of bike fitting are available - from rough settings based on body dimensions to professional services making use of sophisticated equipment and expert knowledge. Modern fitting techniques use mainly joint angles as a criterion of proper position. In this work we examine performance of two proposed methods for dynamic cyclist position assessment based on video data recorded during stationary cycling. Proposed methods are intended for home use, to help amateur cyclist improve their position on the bike, and therefore no professional equipment is used. As a result of data processing, ranges of angles in selected joints are provided. Finally strengths and weaknesses of both proposed methods are discussed.

A dedicated absorption spectroscopy system was set up using tungsten-halogen broadband source, optical fibers, sample holder, and a commercial spectrometer with CCD array. Analysis of noise present in the setup was carried out. Data processing was applied to the absorption spectra to reduce spectral noise, and improve the quality of the spectra and to remove the baseline level. The absorption spectra were measured for whole blood samples, separated components: plasma, saline, washed erythrocytes in saline and human whole blood with biomarkers - biocompatible nanodiamonds (ND). Blood samples had been derived from a number of healthy donors. The results prove a correct setup arrangement, with adequate preprocessing of the data. The results of blood-ND mixtures measurements show no toxic effect on blood cells, which proves the NDs as a potential biocompatible biomarkers.

Respiration is the main reason of the chest movements. However, there are also non-respiratory ones, resulting from e.g. snoring, wheezing, stridor, throat clearing or coughing. They may exist sporadically, however should be examined in case when their incidences increase. Detecting non-respiratory movements is very important, because many of them are symptoms of respiratory diseases such as asthma, chronic obstructive pulmonary disease (COPD) or lung cancer. Assessment of the presence of non-respiratory movements could be important element of effective diagnosis. It is also necessary to provide quantitative and objective results for intra-subject studies. Most of these events generate vibroacoustic signals that contain components of sound and vibrations. This work provides the review of the solutions and devices for monitoring of the non-respiratory movements, primarily considering the accuracy of the chest movements' detection and distinguishing.

This paper presents the design of a compact, wearable, rechargeable acceleration recorder to support long-term monitoring of ambulatory patients with motor disorders, and of software to display and analyze its output. The device consists of a microcontroller, operational amplifier, accelerometer, SD card, indicator LED, rechargeable battery, and associated minor components. It can operate for over a day without charging and can continuously collect data for three weeks without downloading to an outside system, as currently configured. With slight modifications, this period could be extended to several months. The accompanying software provides flexible visualization of the acceleration data over long periods, basic file operations and compression for easier archiving, annotation of segments of interest, and functions for calculation of various parameters and detection of immobility and vibration frequencies. Applications in analysis of gait and other movements are discussed.

Introduction: Bioelectrical impedance analysis (BIA) is a useful tool to asses human body composition and nutrition status; multi-frequency BIA has a higher accuracy than single-frequency BIA. In our study a difference of impedance values (Z) at 5, 100 and 200 kHz and Z200/Z5 index between professional athletes and control group were determined.

Methods: In this research 105 people were tested, divided into control group (72 people: 35 males and 37 females) and professional athletes (33 people: 16 males and 17 females). Impedance was measured at three frequency values - 5, 100 and 200 kHz; with received values the Z200/Z5 index was calculated.

Results: In most compared subgroups impedance values showed significantly lower values in athletes than in control group (5 kHz - males: p=0.136, females: p=0.001, 100 kHz - males: p=0.039, females: p<0.0001, 200 kHz - males: p=0.047, females: p<0.0001); Z200/Z5 index also showed lower value in athletes than in control group (p=0.016 for males, p<0.0001 for females).

Conclusion: Lower values of impedance and Z200/Z5 index indicates a better nutrition status and general health condition of athletes than in control group.

An important computational challenge is finding the regulatory elements across the promotor region. In this work we present the advantages and disadvantages from the application of different bioinformatics programs for localization of transcription factor binding sites in the upstream region of genes connected with sex determination in cucumber. We use PlantCARE, PlantPAN and SignalScan to find motifs in the promotor regions. The results have been compared and possible function of chosen motifs has been described.

The new sequencing methods, called Next Generation Sequencing gives an opportunity to possess a vast amount of data in short time. This data requires structural and functional annotation. Functional identification and characterization of predicted proteins could be done by in silico approches, thanks to a numerous computational tools available nowadays. However, there is a need to confirm the results of proteins function prediction using different programs and comparing the results or confirm experimentally. Here we present a bioinformatics pipeline for structural and functional annotation of proteins.

The haemodynamics of the arterial system can be described by the three-elements Windkessel model. As it is a lumped model, it does not account for pulse wave propagation phenomena: pulse wave velocity, reflection, and pulse pressure profile changes during propagation. The Modelflow© method uses this model to calculate stroke volume and total peripheral resistance (TPR) from pulse pressure obtained from finger; the reliability of this method is questioned.

The model parameters are: aortic input impedance (Zo), TPR, and arterial compliance (Cw). They were obtained from studies of human aorta preparation. Individual adjustment is performed based on the subject’s age and gender. As Cw is also affected by diseases, this may lead to inaccuracies.

Moreover, the Modelflow© method transforms the pulse pressure recording from the finger (Finapres©) into a remarkably different pulse pressure in the aorta using a predetermined transfer function — another source of error.

In the present study, we indicate a way to include in the Windkessel model information obtained by adding carotid pulse recording to the finger pressure measurement. This information allows individualization of the values of Cw and Zo. It also seems reasonable to utilize carotid pulse, which better reflects aortic pressure, to individualize the transfer function.

Despite its simplicity, the Windkessel model describes essential phenomena in the arterial system remarkably well; therefore, it seems worthwhile to check whether individualization of its parameters would increase the reliability of results obtained with this model.

Electrophysiological recording of neuronal action potentials from behaving animals requires portable, precise and reliable devices for positioning of multiple microelectrodes in the brain. We propose a semi-automatic microdrive system for independent positioning of up to 8 electrodes (or tetrodes) in a rat (or larger animals). Device is intended to be used in chronic, long term recording applications in freely moving animals. Our design is based on independent stepper motors with lead screws which will offer single steps of ~ μm semi-automatically controlled from the computer. Microdrive system prototype for one electrode was developed and tested. Because of the lack of the systematic test procedures dedicated to such applications, we propose the evaluation of the prototype similar to ISO norm for industrial robots. To this end we designed and implemented magnetic linear and rotary encoders that provided information about electrode displacement and motor shaft movement. On the basis of these measurements we estimated repeatability, accuracy and backlash of the drive. According to the given assumptions and preliminary tests, the device should provide greater accuracy than hand-controlled manipulators available on the market. Automatic positioning will also shorten the course of the experiment and improve the acquisition of signals from multiple neuronal populations.

ECG signal parameters are commonly used indicators of human health condition. In most cases the patient should remain stationary during the examination to decrease the influence of muscle artifacts. During physical activity, the noise level increases significantly. The ECG signals were acquired during controlled physical activity on a stationary bicycle and during rest. Afterwards, the signals were processed using a method based on Pan-Tompkins algorithms to estimate their parameters and to test the method.

The research aims to design and manufacture of wireless optogenetics devices for freely moving animals in cages IntelliCage system. The purpose of the device is to stimulate specific brain regions using light. The constructed device consists of a light source and optical fibre structure responsible for delivering light into the corresponding region of the brain of the animal. The size of the animal (mouse) and the fact that it is freely moving imposes substantial limitations with respect to the size and weight of the optoelectronic device. The present paper describes research on optical fibre structure fabrication, assembling it to the small size (less than 500 × 500 μm² top surface) LED chip and experimental validation of the optoelectronic stimulator.

In the paper the authors present the developed optoelectronic set for measuring spectral reflectance of living human skin. The basic elements of the set are: the illuminator consists of the LED illuminator emitting a uniform distribution of spectral irradiance in the exposed field, the semispherical measuring chamber and the spectrometer which measures spectrum of reflected radiation. Measured radiation is from spectral range of tissue optical window (from 600 nm to 1000 nm). Knowledge about the reflectance spectrum of the patient skin allows adjusting spectral and energetic parameters of the radiation used in biostimulation treatment. The developed set also enables the repeatable exposures of patients in the Low Level Laser Therapy procedures.

Most of the existing models of cardiovascular system do not take into account the leakage of blood through a number of small vessels branching the main arterial trunks and called perforators. Therefore, the aim of this study is to investigate their influence on the pulse pressure waveform. Linearized, 1D computer model of a minute part of the cardiovascular system has been designed and series of simulations with and without leakage have been conducted. Blood flow in a single segment of the arterial system and pressure in vascular nodes were described by the two first order partial differential equations. A set of boundary conditions on both ends of a single vascular segment and at nodal point have been formulated. To solve the linear set of above equations, a numerical method of characteristic has been used. It was shown that the leakage reduces reflection from the peripheral resistance. The simulations have also shown a decrease of the average pressure value with increase of leakage and modification of the pulse pressure waveform. All these effects depended strongly on the assumed leakage value and practically died out when its value was reduced to about 10% of the main flow.

In this paper, the problem of automatic determination of the position and measuring the thickness of the human skin layers in high-frequency ultrasound images (HFUS) is solved. Location and the process of position determination of the skin layers are not an obvious process due to the phenomenological nature of the images received in HFUS, the so-called speckle noise and the lack of the objective measures. In order to determine the positions of the boundaries of the skin layers, the image analysis methods were used, based on the specific features of the HFUS images, such as layered structure and echogenicity features.

Only the fusion of the results of the analysis algorithms based on global (histogram of intensity levels) and local image features (cross-sectional and topological characteristics) improves discriminative features applicable to complete the information about the properties of the HFUS images with layered structure and to develop a method assessing the thickness of the skin layers. The knowledge gathered from such layers checks can improve understanding of the nature of the human skin and provide a more objective conditions for HFUS diagnostic imaging with speeding up the diagnostic process for dermatologists.

We proposed a new method for automatic segmentation on HFUS images using fusion of discriminative information based on nonlinear segmentation with a reasonable threshold setting, boundary selecting and linking, and false boundary point removing strategies for intensity distributions.

Solving channel equalization problem in communication systems is based on adaptive filtering algorithms. Today, Mobile Agents (MAs) with Recurrent Neural Networks (RNNs) can be also adopted for effective interference reduction in modern wireless communication systems (WCSs). In this paper MAs with RNNs are proposed as novel computing algorithms for reducing interferences in WCSs performing an adaptive channel equalization. The method to provide it is so called MAs-RNNs. We perform the implementation of this new paradigm for interferences reduction. Simulations results and evaluations demonstrates the effectiveness of this approach and as better transmission performance in wireless communication network can be achieved by using the MAs-RNNs based adaptive filtering algorithm.

In this paper several structures of equalizers for carrierless amplitude-phase (CAP) modulation applied in intensity-modulation direct-detection optical links are compared. Minimax optimization method is applied to seek for equalizer weights. Discussed are: modulation format independent equalizer, CAP specific feed forward equalizer and infinite impulse response equalizer. It is shown that the classical CAP equalizer might be inefficient in terms of resource use.

The brilliant idea of Adaptive Feedback Control Systems (AFCS) makes possible creation of highly efficient adaptive systems for estimation, identification and filtering of signals and physical processes. The research problem considered in this paper is: how performance of AFCS changes if some of the assumptions used to formulate iterative estimation algorithm are not fulfilled exactly. To limit the scope of research a particular implementation of the AFCS concept was considered, i.e. an adaptive feedback measurement system (AFMS). The iterative measurement algorithm used was derived under some idealized conditions, notably with perfect knowledge of the system model and Gaussian communication channels. The selected non-idealities of interest are non-zero mean value of noise processes and non-ideal calibration of transmission gain in the forward channel - because they are related to intrinsic non-idealities of analog building blocks, used for the AFMS implementation. The presented original analysis of the iterative measurement algorithm provides quantitative information on speed of convergence and limit behavior. The analysis should be useful for AFCS implementors in the measurement area - since the results are presented in terms of accuracy and precision of iterative measurement process.

The paper presents the results of studies on the behavior of adaptive cyclic analog-to-digital converters (ADCs) for greater number of cycles (iterations) of the sample conversion. A distinguishing feature of the adaptive cyclic ADCs is iterative calculation of output codes of converted samples using a simple digital processing unit (DPU) according to dedicated conversion algorithm. Previous research showed that application of DPU extends radically the possibility of analytical and simulation analysis of cyclic ADCs functioning and allows to improve the effective resolution of the ADCs in comparison with similar conventional sub-ranging cyclic ADCs forming the output codes using logic elements. Moreover, DPU and possibility of optimization of the adaptive cyclic ADCs create a number of new effects important for applications, unachievable in known cyclic ADCs. One of them is restoration of monotonic growth of the adaptive cyclic ADC resolution in the "post-threshold" cycles of conversion, where resolution of conventional cyclic ADCs is fixed without possibility of improvement by increasing number of cycles. In the paper, there is proposed and analyzed a new conversion algorithm for the adaptive cyclic ADCs that combines the most desired features of the algorithms developed earlier, i.e. provides the greatest possible rate of increase of effective number of bits (ENOB) of ADC in the initial "pre-threshold" phase of conversion, and enables further increase of ENOB in the "post-threshold" phase.

Inertial navigation is widely used by the military, in logistics and sailing. In mobile devices, inertial sensors are mostly used as a support for GPS and Wi-Fi-based navigation systems. Inertial-based navigation might prove useful on mobile devices running Android OS. At present, in spite of the accelerometer sensor's precision having been greatly improved, as well as the devices’ computing power continuously rising, inertial navigation's precision still suffers. For smartphones, the key solution seems to be the usage of sensor fusion and signal smart filtering, both discussed in this paper. The paper also describes implementation of inertial navigation in Android devices, their analysis as well as test results.

The H.265/HEVC is the state of the art video compression standard, which allows the bitrate reduction up to 50% with equal perceptual video quality compared with its predecessor. Due to its complexity, the H.265/HEVC encoder must cope with the plurality of features and available prediction modes. The potential acceleration of the encoding process could be achieved by skipping some prediction modes and introducing simplifications in search and mode decision. Therefore, in development of video encoders, the trade-off between quality and complexity must be considered. This paper presents the analysis of the reduction of the number of checked prediction and partitioning modes in inter prediction and transformation in the hardware H.265/HEVC encoder.

The paper discusses particularities of optimal adaptive communication systems (AFCS) design conditioned by the particularities of their architecture and way of functioning, as well as by the approach to their design. The main one is that AFCS employ the analog method of transmission (in the paper - amplitude modulation), and are intended for short-range transmission of signals from the analog sources. Another one is that AFCS design is carried out on the basis of strict results of concurrent analytical optimisation of the transmitting and receiving parts of the system. Below, general problems appearing during transition from the theoretical results to the real engineering design, as well as approach to their solution are discussed. Some concrete tasks of AFCS design are also considered.

The paper describes an investigation of transmission in LAN with using polymer optical fiber (POF). There were used two kinds of POF, step index plastic optical fiber (SI-POF) and graded index plastic optical fiber (GI-POF). Furthermore, the paper include a comparison between SI-POF and GI-POF and possibilities of using them. For the project’s needs, new type of couplers has been designed and built, optimization has been performed to obtain the best parameters for designed couplers. Additionally, the coupler has been built from the same material, which GI-POF – PMMA is made of. Moreover, CWDM (Coarse Wavelength Division Multiplexing) transmissions is investigated to improve the network capacity.

Visual data stereoscopic 3D reconstruction is an important challenge in the LHC ALICE detector experiment. Stereoscopic visualization of 3D data is also an important subject of photonics in general. In this paper we have proposed several solutions enabling effective perception based stereoscopic visualization of data provided by detectors in high energy physics experiments.

The following article describes proposed objective method for a 3DTV video quality evaluation, a Compressed Average Image Intensity (CAII) method. Identification of the 3DTV service's content chain nodes enables to design a versatile, objective video quality metric. It is based on an advanced approach to the stereoscopic videostream analysis. Insights towards designed metric mechanisms, as well as the evaluation of performance of the designed video quality metric, in the face of the simulated environmental conditions are herein discussed. As a result, created CAII metric might be effectively used in a variety of service quality assessment applications.

Detection of characteristic eye points under challenging light conditions is a non-trivial task. Difficulty of this task increase even more when low resolution images are used. This article introduces an adaptive solution for detection of characteristic eye points in mentioned conditions. First, light normalization algorithm is performed. Then, face and eye detection followed by determination of eye status (namely: open or closed) is done. Finally, an adaptive method for pupil and eye corners detection is developed by comparing some existing methods. Experimental results show the outperformance of the proposed method.

The paper is devoted to studies on possibilities of realization of guitar audio effects by means of methods of digital signal processing. As a result of research, some selected audio effects corresponding to the specifics of guitar sound were realized as the real-time system called Digital Guitar Multi-effect. Before implementation in the system, the selected effects were investigated using the dedicated application with a graphical user interface created in Matlab environment. In the second stage, the real-time system based on a microcontroller and an audio codec was designed and realized. The system is designed to perform audio effects on the output signal of an electric guitar.

The paper presents a method of noise reduction in CT images by the curvelet transform. Noise affects the ability to visualize pathologic qualities and the living tissues structure in CT. Noise in CT images depends on the amount of discrete x-ray photons reaching the detector. In the CT images, noise is responsible for visibility reduction the low contrast areas and objects. Noisy picture may not be properly interpreted by a physician, especially for the case of detection of pathological changes in tissues. The tests were performed with the Shepp-Logan test image with additive Gaussian noise.

Development of new biometric algorithms is parallel to advances in technology of sensing devices. Some of the limitations of the current face recognition systems may be eliminated by integrating 3D sensors into these systems. Depth sensing devices can capture a spatial structure of the face in addition to the texture and color. This kind of data is yet usually very voluminous and requires large amount of computer resources for being processed (face scans obtained with typical depth cameras contain more than 150 000 points per face). That is why defining efficient data structures for processing spatial images is crucial for further development of 3D face recognition methods. The concept described in this work fulfills the aforementioned demands. Modification of the quad-tree structure was chosen because it can be easily transformed into less dimensional data structures and maintains spatial relations between data points. We are able to interpret data stored in the tree as a pyramid of features which allow us to analyze face images using coarse-to-fine strategy, often exploited in biometric recognition systems.

The article presents a comparison of the Intra prediction algorithms in the current state-of-the-art video coding standards, including MJPEG 2000, VP8, VP9, H.264/AVC and H.265/HEVC. The effectiveness of techniques employed by each standard is evaluated in terms of compression efficiency and average encoding time. The compression efficiency is measured using BD-PSNR and BD-RATE metrics with H.265/HEVC results as an anchor. Tests are performed on a set of video sequences, composed of sequences gathered by Joint Collaborative Team on Video Coding during the development of the H.265/HEVC standard and 4K sequences provided by Ultra Video Group. According to results, H.265/HEVC provides significant bit-rate savings at the expense of computational complexity, while VP9 may be regarded as a compromise between the efficiency and required encoding time.

One of the means of assessing the state of combustion process is analyzing data obtained from flame images. Flame images can be used as a source of information of combustion process input parameters such as air flow, fuel expense or fumes temperature. These parameters are crucial for stable and effective combustion. Considering complexity of combustion process and large number of fluctuating variables, genetic programming is an approach that seems most appropriate. Several video streams of co-combusting biomass and coal were recorded at the rate of 150 frames per second with 800x800 resolution. Different image and combustion parameters were processed to determine dependencies between them.

This paper develops a modelling method and a models identification technique for the nonlinear dynamic audio systems. Identification is performed by means of a behavioral approach based on a polynomial approximation. This approach makes use of Discrete Fourier Transform and Harmonic Balance Method. A model of an audio system is first created and identified and then it is simulated in real time using an algorithm of low computational complexity. The algorithm consists in real time emulation of the system response rather than in simulation of the system itself. The proposed software is written in Python language using object oriented programming techniques. The code is optimized for a multithreads environment.

A real-time tracking and mapping SLAM system is presented. The developed system uses input from an RGBD sensor and tracks the camera pose from frame to frame. The tracking is based on matched feature points and is performed with respect to selected keyframes. The system is robust and scalable, as an arbitrary number of keyframes can be chosen for visualization and tracking depending on the desired accuracy and speed. The presented system is also a good platform for further research.

In the age of modern, hyperconnected society that increasingly relies on mobile devices and solutions, implementing a reliable and accurate biometric system employing iris recognition presents new challenges. Typical biometric systems employing iris analysis require expensive and complicated hardware. We therefore explore an alternative way using visible spectrum iris imaging.

This paper aims at answering several questions related to applying iris biometrics for images obtained in the visible spectrum using smartphone camera. Can irides be successfully and effortlessly imaged using a smartphone's built-in camera? Can existing iris recognition methods perform well when presented with such images? The main advantage of using near-infrared (NIR) illumination in dedicated iris recognition cameras is good performance almost independent of the iris color and pigmentation. Are the images obtained from smartphone's camera of sufficient quality even for the dark irides?

We present experiments incorporating simple image preprocessing to find the best visibility of iris texture, followed by a performance study to assess whether iris recognition methods originally aimed at NIR iris images perform well with visible light images. To our best knowledge this is the first comprehensive analysis of iris recognition performance using a database of high-quality images collected in visible light using the smartphones flashlight together with the application of commercial off-the-shelf (COTS) iris recognition methods.

The principal rule of the conservation process is an individual approach to every piece of art. Easel paintings are varying regarding their forms (shape), technique and technology and behave differently in various conditions. In order to carry out initial researches of the particular object several noninvasive analyzes are performed. However, none of these methods give information about geometric shape of the object and metric analysis of its surface. This gap in the field of initial optical analysis, may be filled with optical 3D scanning. From conservators' point of view, we may say that a laser scanner slowly becomes an indispensable and daily work tool in the diagnosis and conservation methodology of the canvas paintings.

Paper describes the method of neutron radiation dosimetry using polyethylene moderator and thermoluminescent detectors. Mechanisms of neutrons’ slowing down, detection and measurement steps using TLD are presented. The paper contains a description of the construction and the arrangements of the multi-moderator with possibility of placing passive detectors at different thicknesses in the sphere. Additionally, there is presented a possibility of ionization chamber utilization as an active part of the spectrometer. Results of geometrical modelling and Monte Carlo simulations are presented. Response matrices for deconvolution purpose were obtained.

The STAR detector at the Relativistic Heavy Ion Collider (RHIC) is equipped with system of dedicated Silicon Strip Detectors housed inside Roman Pot vessels, allowing to detect protons scattered at small angles. Data from polarized proton-proton collisions at center-of-mass system (c.m.s.) energy √s = 200 GeV collected with special settings of RHIC magnet lattice (β * = 22 m) allow to study proton-proton elastic scattering at very low values of squared four-momentum transfer (Mandelstam t), 0:003 ≤ −t ≤ 0:035 GeV²=c². Results of analysis of systematic effects and large statistics of collected data sample reveal possibility of measurement of the Nuclear Slope Parameter with precision not yet achieved at this c.m.s. energy.

A Digital Signal Processing method for Neutron Gamma Discrimination [1] is described in this paper. A Singular Value Decomposition (SVD) was used for estimation noiseless signal shape. Based on this shape, detection method was introduced. This method uses projection operation into signal and noise subspace and Signal to Noise Ratio estimation. This method was compared with another one proposed by [2]. Booth method was implemented in MATLAB. Computation was done on signals from scintillators. Data acquisition was dome with high quality hardware. The Neutron Gamma Discrimination algorithm operate on digital samples from ADC converter. Hardware used for data acquisition in this this paper was described in [3]. On the end, the results of this two methods was presented and compared. The signal model in this methods assume additional, white, Gaussian noise.

Performance and functionality of radiation imaging detector circuits in charge and position measurement systems need to meet tight requirements. It is therefore necessary to thoroughly test sensors as well as read-out electronics. The major disadvantages of using radioactive sources or particle beams for testing are high financial expenses and limited accessibility. As an alternative short pulses of well-focused laser beam are often used for preliminary tests. There are number of laser-based devices available on the market, but very often their applicability in this field is limited. This paper describes concept, design and validation of laser system for testing silicon sensor based radiation imaging detector circuits. The emphasis is put on keeping overall costs low while achieving all required goals: mobility, flexible parameters, remote control and possibility of carrying out automated tests. The main part of the developed device is an optical pick-up unit (OPU) used in optical disc drives. The hardware includes FPGA-controlled circuits for laser positioning in 2 dimensions (horizontal and vertical), precision timing (frequency and number) and amplitude (diode current) of short ns-scale (3.2 ns) light pulses. The system is controlled via USB interface by a dedicated LabVIEW-based application enabling full manual or semi-automated test procedures.

Multivariate techniques using machine learning algorithms have become an integral part in many High Energy Physics (HEP) data analyses. The article shows the gain in physics reach of the physics experiments due to the adaptation of machine learning techniques. Rapid development in the field of machine learning in the last years is a challenge for the HEP community. The open competition for machine learning experts “Higgs Boson Machine Learning Challenge” shows, that the modern techniques developed outside HEP can significantly improve the analysis of data from HEP experiments and improve the sensitivity of searches for new particles and processes.

This article proposes new method of storing data and transferring it to PC in the X-ray GEM detector system. The whole process is performed by FPGA chips (Spartan-6 series from Xilinx). Comparing to previous methods, new approach allows to store much more data in the system. New, improved implementation of the communication algorithm significantly increases transfer rate between system and PC. In PC data is merged and processed by MATLAB. The structure of firmware implemented in the FPGAs is described.

Soft X-ray (SXR) measurement systems working in tokamaks or with laser generated plasma can expect high photon fluxes. Therefore it is necessary to focus on data processing algorithms to have the best possible efficiency in term of processed photon events per second. This paper refers to recently designed algorithm and data-flow for implementation of charge data acquisition in FPGA. The algorithms are currently on implementation stage for the soft X-ray diagnostics system. In this paper despite of the charge processing algorithm is also described general firmware overview, data storage methods and other key components of the measurement system. The simulation section presents algorithm performance and expected maximum photon rate.

This paper describes recently developed system for diagnostics of high-voltage power supply section of tokamaks’. Such system is necessary for real-time monitoring of high-voltage power supply section with ability to perform automatic and fast decisions related to protection system. The system is distributed, allowing data acquisition of components installed away from the systems’ controller. Remote communication is based on fiber links. Main processing units are FPGA circuits. The system can pass-through analog and digital signals from local to remote or remote to local locations. In the main FPGA unit, independent user developed algorithms can be implemented. The system structure is based on the uTCA standard. The micro TCA crate controller is implemented as PC unit in AMC standard. Communication is based on gigabit transceivers providing low-latency of data transmission. The system is working with specialized diagnostics and control software. The graphical user interface is provided for the end user. Several tests were made in term of data latency, proper signal transmission and system control.

This article concerns optimization methods for data analysis for the X-ray GEM detector system. The offline analysis of collected samples was optimized for MATLAB computations. Compiled functions in C language were used with MEX library. Significant speedup was received for both ordering-preprocessing and for histogramming of samples. Utilized techniques with obtained results are presented.

This article is an assessment of potential parallelization of histogramming algorithms in GEM detector system. Histogramming and preprocessing algorithms in MATLAB were analyzed with regard to adding parallelism. Preliminary implementation of parallel strip histogramming resulted in speedup. Analysis of algorithms parallelizability is presented. Overview of potential hardware and software support to implement parallel algorithm is discussed.

This paper describes system for a diagnostics of a high-voltage power supply section of tokamaks. System is designed to assure reliability and safety of power supply subsystems. It is divided into two main components: remote and local. Remote part is located near tokamak, whereas local part can be localised away from the tokamak area. The remote side consists of custom, standalone devices. On the other hand, the local device is based on the uTCA.4 architecture. Components are connected with an optic fibre over a link-layer protocol which provides high throughput, low latency and transmission redundancy. All main operations ie. data processing, transmission etc. are performed on the FPGA devices. At the local side there is one device treated as a master device. It implements sort of a routing table which connects consecutive system inputs and outputs. It also provides possibility for some user defined data processing. This document contains general system overview, short description of hardware used in the project and gateware implementation.

In this paper the object oriented hardware-software model and its sample implementation of diagnostics for the Overlap Muon Track Finder trigger for the CMS experiment in CERN is described. It presents realization of test-bench for control and diagnosis class of multichannel, distributed measurement systems based on FPGA chips. The test-bench fulfills requirements for system’s rapid changes, configurability and efficiency. This ability is very significant and desirable by expanded electronic systems. The solution described is a software model based on a method of address space management called the Component Internal Interface (CII). Establishment of stable link between hardware and software, as a purpose of designed and realized programming environment, is presented. The test-bench implementation and example of OMTF algorithm test is presented.

The Compressed Baryonic Matter (CBM) experiment is a part of the Facility for Antiproton and Ion Research (FAIR) in Darmstadt at GSI. In CBM experiment a precisely time synchronized fault tolerant self-triggered electronics is required for Data Acquisition (DAQ) system in CBM experiments which can support high data rate (up to several TB/s). As a part of the implementation of the DAQ system of Muon Chamber (MUCH) which is one of the important detectors in CBM experiment, a FPGA based Gigabit Transceiver (GBTx) emulator is implemented. Readout chain for MUCH consists of XYTER chips (Front end electronics) which will be directly connected to detector, GBTx emulator, Data Processing Board (DPB) and First level event selector board (FLIB) with backend software interface. GBTx emulator will be connected with the XYTER emulator through LVDS (Low Voltage Differential Signalling) line in the front end and in the back end it is connected with DPB through 4.8 Gbps optical link. IPBus over Ethernet is used for internal monitoring of the registers within the GBTx. In IPbus implementation User Datagram Protocol (UDP) stack is used in transport layer of OSI model so that GBTx can be controlled remotely. A Python script is used at computer side to drive IPbus controller.

In this paper feasibility studies of the exclusive diffractive bremsstrahlung at RHIC energies are presented. The analysis exploits a simplified approach of the radiated photon and the scattered proton measurement. A brief discussion of possible backgrounds is given.

This paper presents the readout concept for the Silicon Tracking System (STS) of the CBM experiment at FAIR, which is designed to handle interaction rates up to 10 MHz with hundreds of tracks in fixed target heavy ion collisions of up to 35 AGeV. For data readout from the frontend electronics located close to the silicon strip sensors, the radiation tolerant Gigabit Transceiver ASICs (GBTx) and Versatile Link optical modules developed at CERN are used.

The usage of these devices in the STS readout and the readout concept from the frontend electronics to the GBT based STS readout board (ROB) are detailed. Special emphasis is put on the implementation of the interface between the frontend boards (FEBs) and the ROB layer.

Successful operation of the Silicon Tracking System requires charge measurement of each hit with equivalent noise charge lower than 1000 e- rms. Detector channels will not be identical, they will be constructed accordingly to the estimated occupancy, therefore for the readout electronics, detector system will exhibit various parameters. This paper presents the simulation-based study on the required microcable (trace width, dielectric material), detector (aluminum strip resistance) and external passives’ (decoupling capacitors) parameters in the Silicon Tracking System. Studies will be performed using a front-end electronics (charge sensitive amplifier with shaper) designed for the power budget of 10 mA/channel.

The paper presents results of time-resolved measurements of fast deuterons emitted from high-current discharges of the Plasma-Focus (PF) type. The measurements were performed in a modified PF-1000U facility which is operated at the IFPiLM in Warsaw, Poland. The device was equipped with a fast-acting gas valve placed inside the inner electrode and oriented along the z-axis. The valve could inject a small volume of a chosen gas in front of this electrode. The PF discharges were initiated at the initial deuterium pressure equal to 1.6 or 2 hPa, with or without the use of the gas-puffing. Such discharges emitted intense beams of accelerated primary ions and X-ray pulses as well as products of nuclear fusion reactions.

The reported measurements of the fast ion beams were performed by means of a Thomson-type spectrometer located at a chosen distance at the z-axis and equipped with miniature scintillation detectors. These detectors were placed in different points upon the deuteron parabola which corresponded to determined energy values. The detectors configuration allowed us to determine instants of the ion emission (using a TOF technique) and to compare them with instants of the X-ray emission. The collected data provided important information about emission characteristics of the modified PF-1000U facility.

The AMC FMC Carrier Kintex (AFCK) board is a prototype of Data Processing Board (DPB) for CBM experiment. AFCK is open hardware and was designed to be a versatile solution, applicable in multiple systems. In CBM experiment AFCK will serve as a data hub and communication interconnection. One of DPB's functions is synchronization of Front End Electronics (FEE). To provide this functionality, it is necessary to receive the reference clock and timing signals from the Timing and Flow Control system. The received clock after the jitter cleaning will be used as a reference clock for GBT-FPGA based 4.8 Gbps links used for communication with front end electronics. This article will briefly describe AFCK board function in CBM experiment. Afterwards it will focus on jitter cleaning technique based on White Rabbit solution that can be used on AFCK board.

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. Multi-channel measurement system and serial data acquisition for X-ray energy and position recognition is described. Fundamental characteristics are presented for two dimensional detector structure. Typical signals of ADC – Analog to Digital Converter are considered for charge value and position estimation. Coinciding signals for high flux radiation cause the problem for cluster charge identification. The amplifier with shaper determines time characteristics and limits the pulses frequency. Separation of coincided signals was introduced and verified for simulation experiments. On line separation of overlapped signals was implemented applying the FPGA technology with relatively simple firmware procedure. Representative results for reconstruction of coinciding signals are demonstrated.

This paper presents a prototype for the readout chain of the Compressed Baryonic Matter (CBM) experiment using the AFCK FPGA board as Data Processing Board (DPB). The components of the readout chain are described, followed by some test setups, all based on different flavors of AFCK-DPB. Details about the functional blocks in the different versions of the DPB firmware are given, followed by a description of the corresponding software elements.

The detecting devices dedicated for plasma monitoring will be exposed for massive fluxes of neutron, photons as well as other rays that are components of fusion reactions and their product interactions with plasma itself or surroundings. In result detecting module metallic components will be activated becoming a source of radiation. Moreover, electronics components could change their electronic properties. The prototype GEM detector constructed for monitoring soft X-ray radiation in ITER oriented tokamaks was used for plasma monitoring during experimental campaign on tokamak ASDEX Upgrade. After that it became a source of gamma radiation caused by neutrons. The present work contains description of detector activation in the laboratory conditions.

The paper presents feasibility and design studies of Cherenkov-type probes, a development of the measuring head construction designed for different tokamak devices, and in particular the acquisition of optical signals to a data storage system. In order to lower the energy threshold of the electron detection the authors applied radiators with the highest values of the refractive index. Different radiator materials, such as aluminium nitride and CVD diamond were applied. Several versions of measuring heads and different manipulators, e.g., a movable vacuum-tight shaft or a fast-moving reciprocating probe, were manufactured and used. The practical application of the Cherenkov probes required also a consideration of spectral characteristics of optical fibres and photomultipliers. The Cherenkov radiation, as generated inside the radiators, is lead out through separate fibres (optical cables) to the atmospheric pressure side. The emitted radiation in the blue (near ultraviolet) spectrum range should be collected and delivered through appropriate optical cables to a control room, amplified within photomultipliers and recorded in a digital form. In order to investigate an electron energy distribution the multi-channel probes have also been designed and applied.

Prototype of Ultra-Fast X-Ray Camera Controller working in a single photon counting mode and based on ASIC has been presented in this paper. An ASIC architecture has been discussed with special attention to digital part. We present the Custom Soft Processor as an ASIC control sequences generator. The Processor allows for dynamic program downloading and generating control sequences with up to 80MHz clock rate (preliminary results). Assembler with a very simple syntax has been defined to speed up Processor programs development. Discriminators threshold dispersion correction has been performed to confirm proper Camera Controller operation.

An increased attention to tungsten material is related to a fact that it became a main candidate for the plasma facing material in ITER and future fusion reactor. The proposed work refers to the studies of W influence on the plasma performances by developing new detectors based on Gas Electron Multiplier GEM) technology for tomographic studies of tungsten transport in ITER-oriented tokamaks, e.g. WEST project. It presents current stage of design and developing of cylindrically bent SXR GEM detector construction for horizontal port implementation. Concept to overcome an influence of constraints on vertical port has been also presented. It is expected that the detecting unit under development, when implemented, will add to the safe operation of tokamak bringing creation of sustainable nuclear fusion reactors a step closer.

Heavy-ions are brought to ultrarelativistic energies in dedicated accelerators. When the ions collide, a system is produced with high temperature and energy density. Its size is initially comparable to the size of a nucleus. Theory predicts that a deconfined state of matter – a Quark-Gluon Plasma is produced in these conditions. However such description implicitly uses thermodynamic properties, such as temperature, chemical potentials etc. In physics such quantities are usually defined only for “large” systems. A question of the actual size of the system in the heavy-ion collision then becomes crucial. A methodology based on two-particle correlations, called “femtoscopy” is used to measure this size. In this work we briefly describe the technique, which is based on the quantum mechanical properties of particle pairs. We discuss examples of correlation functions and describe a procedure of extracting the “femtoscopic radii”. We show selected recent experimental results for these radii. We also give the theoretical interpretation and consequences for the model description of the heavy-ion collision evolution.

Results are reported on using evaporation and UHV arc lead deposition to create thin-layer superconducting Pb photocathodes on niobium wall of electron gun. Evaporated photocathodes were prepared and tested for the first time in 2014. A complete XFEL-type photo-injector with an evaporated photocathode underwent successful quality check at DESY - an acceptable working point was reached. On the other hand poor adhesion to niobium proved to be the most serious shortcoming of the evaporated Pb layers. UHV arc deposition seems to be much more promising in this context as it allows energetic coating. Filtered arc coating lead to creation of uniform, 2 μm thick lead layers with casual spherical extrusions which enhance locally electric field and leads to high dark current. Conditioning in electric field is needed to reduce the field emission effects from these layers to acceptably low value. Using non-filtered UHV lead deposition enabled fast coating up to a thickness above 10 μm. Pb films obtained in this way require further post-processing in pulsed plasma ion beams in a rod plasma injector. In order to reach a sufficiently planar film surface the pulsed heat flow through a lead layer on niobium was modeled and computed.

Solaris synchrotron storage ring which has been assembled at the beginning of the 2015, consist of twelve integrated magnets blocks performing the part of double bend achromat. Both magnets as well as the whole ring as concept is a replica of Max IV 1.5 GeV ring and utilize pioneering integrated magnets approach. Solaris ring assembly forewent that of its Swedish twin. It is a successful proof of principle experiment showing the feasibility of the chosen approach. On the other hand it was an exercise which brought the knowledge on mechanical behavior of the magnets blocks and matching components, which is of unique importance for further integrated magnets implementations. Hereby we present selected issues related to the ring assembly: block stiffness verification and straightness rectification, vacuum chamber installation, alignment and mechanical stability of the assembled system.

The Fast Beams Condition Monitor (BCM1F), upgraded for LHC Run II, is used to measure the online luminosity and machine induced background for the CMS experiment. The detector consists of 24 single-crystal CVD diamond sensors that are read out with a custom fast front-end chip fabricated in 130 nm CMOS technology. Since the signals from the sensors are used for real time monitoring of the LHC conditions they are processed by dedicated back-end electronics to measure separately rates corresponding to LHC collision products, machine induced background and residual activation exploiting different arrival times. The system is built in MicroTCA technology and uses high speed analog-to-digital converters. In operational modes of high rates, consecutive events, spaced in time by less than 12.5 ns, may cause partially overlapping events. Hence, novel signal processing techniques are deployed to resolve overlapping peaks. The high accuracy qualification of the signals is crucial to determine the luminosity and the machine induced background rates for the CMS experiment and the LHC.

Biological effectiveness of any type of radiation can be related to absorbed dose versus linear energy transfer (LET) associated with the particular radiation field. In complex radiation fields containing neutrons, especially in fields of high-energy particles or in stray radiation fields, radiation quality factor can be determined using detectors which response depends on LET. Recombination chambers, which are high-pressure, tissue equivalent ionization chambers operating under conditions of initial recombination of ions form a class of such detectors.

Recombination Microdosimetric Method (RMM) is based on analysis of the shape of current-voltage characteristic (saturation curve) of recombination chamber. The ion collection process in the chamber is described by theoretical formula that contains a number of coefficients which depend on LET. The coefficients are calculated by fitting the shape of the theoretical curve to the experimental data.

The purpose of the present project was to develop such a program for determination of radiation quality factor, basing on calculation of dose distribution versus LET using RMM.

In this paper a model of web application‘s source code, based on the OSD ontology (Ontology for Software Development), is proposed. This model is applied to implementation and maintenance phase of software development process through the DevOntoCreator tool [5]. The aim of this solution is decreasing software complexity of that source code, using many different maintenance techniques, like creation of documentation, elimination dead code, cloned code or bugs, which were known before [1][2]. Due to this approach saving on software maintenance costs of web applications will be possible.

The positivity and asymptotic stability of time-varying discrete-time and continuous-time linear systems and electrical circuits are addressed. Necessary and sufficient conditions for the positivity of the time-varying linear systems and electrical circuits are established. Using the extension to positive fractional systems of the Lyapunov method the asymptotic stability of positive systems and electrical circuits is shown. Conditions for the positivity of descriptor time-varying discrete-time linear systems are established. Examples of positive and asymptotically stable systems and electrical circuits are presented.

Present systems and devices are usually protected against different threats concerning digital data processing. The protection mechanisms consume resources, which are either highly limited or intensively utilized by many entities. The optimization of these resources usage is advantageous. The resources that are saved performing optimization may be utilized by other mechanisms or may be sufficient for longer time. It is usually assumed that protection has to provide specific quality and attack resistance. By interpreting context situation of business services - users and services themselves, it is possible to adapt security services parameters to countermeasure threats associated with current situation. This approach leads to optimization of used resources and maintains sufficient security level. This paper presents architecture of adaptive security service, which is context-aware and exploits quality of context data issue.

The real art of management it is important to make smart decisions, what in most of the cases is not a trivial task. Those decisions may lead to determination of production level, funds allocation for investments etc. Most of the parameters in decision-making process such as: interest rate, goods value or exchange rate may change. It is well know that these parameters in the decision-making are based on the data contained in datamarts or data warehouse. However, if the information derived from the processed data sets is the basis for the most important management decisions, it is required that the data is accurate, complete and current. In order to achieve high quality data and to gain from them measurable business benefits, data quality system should be used. The article describes the approach to the problem, shows the algorithms in details and their usage. Finally the test results are provide. Test results show the best algorithms (in terms of quality and quantity) for different parameters and data distribution.

This paper presents a research that aims to compare effects of faults on different configurations of computer systems. The study covers comparison of susceptibility to faults of x86, AMD64, ARM, PowerPC, MIPS architectures and Linux, FreeBSD, Minix operating systems. An emulation based software implemented fault injection technique was used to perform experiments. The problem of choosing an adequate number of tests in experiments is followed by report with collected results where multiple aspects of test runs were analyzed: providing correct computation result, availability of the system under test and error messages. The research allows to determine characteristics of susceptibility to faults of each platform and is a first step towards designing new fault tolerance solutions and assessing their effectiveness.

Contemporary computer systems provide mechanisms for monitoring various performance parameters (e.g. processor or memory usage, disc or network transfers), which are collected and stored in performance logs. An important issue is to derive characteristic features describing normal and abnormal behavior of the systems. For this purpose we use various schemes of analyzing time series. They have been adapted to the specificity of performance logs and verified using data collected from real systems. The presented approach is useful in evaluating system dependability.

This article describes an approach to the analysis of historical debuggers logs (execution traces). Historical debuggers are tools that provide insight into the history of programs execution. The author focuses on finding execution patterns of subprograms in these logs in an efficient way and proposes a method of visualising them. Execution patterns are a form of automatically generated specification/documentation of software which show usage of subprograms. In order to discover them in execution traces an existing algorithm was adapted. This algorithm is based on suffix arrays and it finds patterns in text application logs in the linear time with the respect to the length of logs. Additionally, Extended Call Graphs were introduced to visualise the execution patterns. They contain more information in comparison with standard call graphs.

Apriori algorithm can generate huge sets of decision rules. A lot of these rules, especially in a multilevel multidimensional environment, are redundant or useless. To reduce this unwanted effect the author proposes to utilise generators or closed itemsets, originally used in lossless itemsets representations, to filter decision rules during their generation. These two modifications of the Apriori algorithm enable reduction of a size of resultant decision rules' sets without lost of information about relations in training data. Choice of the proposed modifications depends on user's preference about length of the rules. Filtering using generators gives shorter rules while filtering with closed itemsets results in smallest sets of rules. Both modifications were evaluated on large sets of training data from faults simulations experiments.

In this article, we are going to present the issue concerning the tautology for the three-valued logic of beliefs – LB3. The aim of the paper is to present a machine implementation of tautology analysis for the given logic. Due to the presented analysis, we can classify a given LB3 language formula as: tautology, contradiction, or a satisfiable function. We also present the method for decoding LB3 logic expressions, since machine implementation of any aspects related to logical systems require proper coding.

In last years, the throughput of interfaces used in computer systems to control extension boards or external hardware has increased significantly. Unfortunately, those interfaces have also significant round-trip latency. This fact seriously impairs the efficiency of those control algorithms, which require a tight handshake. In such algorithms, the communication consists of a sequence of write and read operations, where read result (the handshake status) must be checked before the next write command is issued. This problem can be solved by the implementation of an intelligent controller in the controlled hardware. This controller should execute high-level commands locally performing all necessary handshake operations. Unfortunately, such a complex and highly specialized controller would consume a significant amount of FPGA resources. This paper presents an alternative approach which uses a highly simplified versatile controller implemented in FPGA. This simple controller may improve the efficiency of certain, relatively broad class of control algorithms. The proposed controller accepts a set of simple commands, which describe the write operations, read operations, and simple test operations. The control algorithm is described as a sequence of those operations. If the controlled hardware works correctly, all tests are passed, and the controller only notifies the host about successful completion. In case if certain handshake test fails, the host is notified about the position of the failed test and type of failure. That allows the controlling software to investigate and cure the problem. The controller may be also used in a standard mode, where status or result of each command is returned immediately and may be checked before the next command is issued.

The paper also proposes a simple method for writing of software, which uses the new controller. This method allows to implement the control procedures that are very similar to those using traditional controllers. That minimizes the effort needed to use the new controller and reduces a risk of errors.

Byzantine fault-tolerant (BFT) replication is a powerful technique for guaranteeing correctness of distributed services despite arbitrary faults. BFT replication protocols are typically composed of two phases: agreement and execution. Although some monolithic solutions exist that incorporate both phases, providing a clear separation between agreement and execution is often desired, due to for instance higher level of abstraction or better resource utilization. At the same time, however, separation can increase latency and reduce throughput, as an additional communication round is typically required to relay the requests between the phases. In this article we address this issue by proposing an approach that reduces the cost of agreement in BFT replication protocols without sacrificing phase separation. The article presents Otonaru, a dedicated sequencer that achieves around 30% higher performance than solutions usually deployed in the agreement phase of modern BFT replication protocols. As a result, the solutions built using the proposed approach can inherit all benefits of separation, at the same time providing a performance competitive to monolithic BFT protocols.

The paper describes an innovative module which autonomously executes frequently used sequences of commands, stored in the peripheral device RAM, and absorbs data from internal slave modules. Due to autonomous operation, significant increase of execution speed of typical control algorithms may be achieved. Depending on the particular algorithm performed, the appropriate operation mode may be selected, eg. the transparent mode for specific algorithms lacking sequences of repeated operations.

This paper presents a python to VHDL compiler. The compiler interprets an algorithmic description of a desired behavior written in Python and translate it to VHDL. FPGA combines many benefits of both software and ASIC implementations. Like software, the programmed circuit is flexible, and can be reconfigured over the lifetime of the system. FPGAs 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. This can be achieved by using many computational resources at the same time. Creating parallel programs implemented in FPGAs in pure HDL is difficult and time consuming. Using higher level of abstraction and High-Level Synthesis compiler implementation time can be reduced. The compiler has been implemented using the Python language. This article describes design, implementation and results of created tools.

There is presented new method of synthesis of application specific logic controllers for FPGA devices. The specification of control algorithm is made with use of control interpreted Petri net (PT type). It allows specifying parallel processes in easy way. The Petri net is decomposed into state-machine type subnets. In this case, each subnet represents one parallel process. For this purpose there are applied algorithms of coloring of Petri nets. There are presented two approaches of such decomposition: with doublers of macroplaces or with one global wait place. Next, subnets are implemented into two-level logic circuit of the controller. The levels of logic circuit are obtained as a result of its architectural decomposition. The first level combinational circuit is responsible for generation of next places and second level decoder is responsible for generation output symbols. There are worked out two variants of such circuits: with one shared operational memory or with many flexible distributed memories as a decoder. Variants of Petri net decomposition and structures of logic circuits can be combined together without any restrictions. It leads to existence of four variants of multi-variants synthesis.

Boosting algorithms constitute one of the essential tools in modern machine-learning, one of its primary applications being the improvement of classifier accuracy in supervised learning. Most widespread realization of boosting, known as AdaBoost, is based upon the concept of building a complex predictive model out of a group of simple base models. We present an approach for local assessment of base model accuracy and their improved weighting that captures inhomogeneity present in real-life datasets, in particular in those that contain geographic information. Conducted experiments show improvement in classification accuracy and F-scores of the modified algorithm, however more experimentation is required to confirm the exact scope of these improvements.

Algorithms for dynamic detection of assertions are designed to find different types of dependences in programs based only on information collected during their execution without static analysis. Specificity of those algorithms and limited quantity of data to analyze needs to investigate the usage principle of discovered assertions for software dependability increase. This article introduces techniques for increasing usage efficiency of detected assertions through using program execution trace. Concept of trace and of an assertion with trace were defined. The work describes algorithms for reducing the number of traces, shortening traces lengths and reducing the number of observation points identifiers in traces. For several applications fault injection based experiments were conducted in order to check the effectiveness of the proposed approach.

In the paper, coloring heuristic algorithm of interpreted Petri nets is presented. Coloring is used to determine the State Machines (SM) subnets. The present algorithm reduces the Petri net in order to reduce the computational complexity and finds one of its possible State Machines cover. The proposed algorithm uses elements of interpretation of Petri nets. The obtained result may not be the best, but it is sufficient for use in rapid prototyping of logic controllers. Found SM-cover will be also used in the development of algorithms for decomposition, and modular synthesis and implementation of parallel logic controllers. Correctness developed heuristic algorithm was verified using Gentzen formal reasoning system.

The goal of the MDA is to produce software systems from abstract models in a way where human interaction is restricted to a minimum. These abstract models are based on the UML language. However, the semantics of UML models is defined in a natural language. Subsequently the verification of consistency of these diagrams is needed in order to identify errors in requirements at the early stage of the development process. The verification of consistency is difficult due to a semi-formal nature of UML diagrams. We propose automatic verification of consistency of the series of UML diagrams originating from abstract models implemented with our consistency rules. This Consistent Model Driven Architecture approach enables us to generate automatically complete workflow applications from consistent and complete models developed from abstract models (e.g. Business Context Diagram). Therefore, our method can be used to check practicability (feasibility) of software architecture models.

In this paper we show how PCA (Principal Component Analysis) method can be implemented using Java programming language. We consider using PCA algorithm especially in analysed data obtained from Raman spectroscopy measurements, but other applications of developed software should also be possible. Our goal is to create a general purpose PCA application, ready to run on every platform which is supported by Java.

Statechart diagram and UML technique can be a vital part of early conceptual modeling. At the present time there is no much support in hardware design methodologies for reconfiguration features of reprogrammable devices. Authors try to bridge the gap between imprecise UML model and formal HDL description. The key concept in author's proposal is to describe the behavior of the digital controller by statechart diagrams and to map some parts of the behavior into reprogrammable logic by means of group of states which forms sequential automaton. The whole process is illustrated by the example with experimental results.

Rule induction is one of the most significant issues in data mining. This is due to the fact that decision rules induced from the training data are used to classify new objects. The classification is based on matching the object with the decision rules. Specifically, the generated rules are used to resolve whether or not the object satisfies the conditions specified by the subset of attributes belonging to a given decision class. Most of the rule induction methods are insufficient for large databases and hence do not support today's Big Data issues. This is mainly due to the use of so-called discernibility matrices during calculations. The purpose of this paper is the idea of the implementation of a new efficient rule induction algorithm that is based on statistics of attribute values and that avoids building the discernibility matrix explicitly. Tests have shown that the implementation is much more efficient than currently available solutions for large data sets.

This paper deals with the problem of adapting sequential frequent item sets mining algorithm to parallel processing. The original Bodon's Apriori algorithm has been partitioned into loosely coupled tasks and prepared to be executed on several computation nodes using Charm++ library. Variety of optimization methods have been proposed and successfully implemented in parallel environment. The work provides enhancements to achieve good efficiency during parallelization of existing solutions, e.g.: how to organize communication between tasks. The presented approach has been illustrated with many experiments and measurements performed on parallelized algorithm.

A number of methods for data reduction have already been proposed in the literature. However, these methods, particularly those based on discernibility matrices, are insufficient for large databases and thus Big Data processing. The purpose of this paper is the introduction of a new efficient feature extraction algorithm that is based on statistics of attribute values. Tests have shown that the implementation is much more efficient than currently available solutions.

Discretization is an important preprocessing step in data mining. The data discretization method involves determining the ranges of values for numeric attributes, which ultimately represent discrete intervals for new attributes. The ranges for the proposed set of cuts are analyzed, in order to obtain a minimal set of ranges while retaining the possibility of classification. For this purpose, a special discernibility function can be constructed as a conjunction of alternative cuts set for each pair of different objects of different decisions- cuts discern these objects. However, the data mining methods based on discernibility matrix are insufficient for large databases. The purpose of this paper is the idea of implementation of a new data discretization algorithm that is based on statistics of attribute values and that avoids building the discernibility matrix explicitly. Evaluation of time complexity has shown that the proposed method is much more efficient than currently available solutions for large data sets.

The paper presents unit testing-based approach to FPGA design in-circuit verification. Presented methodology is dedicated to modular reconfigurable logic controllers, but other ip-cores and systems can be verified as well. The speed and reproducibility of tests is key for rapid system prototyping, where the quality and reliability of the system is significance. Typically FPGA are programmed by means single (full) bitstream. Specific devices are able to be reconfigured partially. Usually the partial reconfiguration is a part of the design functionality. It enables the minimization of used resources or provides specific functionality like system adaptation. The paper presents the use of the partial reconfiguration as a toll for the designer. The unit testing approach well know form software engineering was adopted to modular logic controllers development. The simulation process results waveform files, the waveform can be used for synthesizable test bench generation.

The method of measurement system software automatic validation using business rules management system (BRMS) is discussed in this paper. The article contains a description of the new approach to measurement systems execution validation, a description of the implementation of the system that supports mentioned validation and examples documenting the correctness of the approach. In the new approach BRMS are used for measurement systems execution validation. Such systems have not been used for software execution validation nor for measurement systems. The benefits of using them for the listed purposes are discussed as well.

This paper shows a method targeted at software execution interpretation and fault detection using recurrence plot analysis. In in the proposed approach recurrence plot analysis is applied to software execution trace that contains executed assembly instructions. Results of this analysis are subject to further processing with PCA (Principal Component Analysis) method that simplifies number coefficients used for software execution classification. This method was used for the analysis of five algorithms: Bubble Sort, Quick Sort, Median Filter, FIR, SHA-1. Results show that some of the collected traces could be easily assigned to particular algorithms (logs from Bubble Sort and FIR algorithms) while others are more difficult to distinguish.

Dependability modeling is an important issue for aerospace and space equipment designers. From system level perspective, one has to choose from multitude of possible architectures, redundancy levels, component combinations in a way to meet desired properties and dependability and finally fit within required cost and time budgets. Modeling of such systems is getting harder as its levels of complexity grow together with demand for more functional and flexible, yet more available systems that govern more and more crucial parts of our civilization's infrastructure (aerospace transport systems, telecommunications, exploration probes). In this article promising method of modeling complex systems using Petri networks is introduced in context of qualitative and quantitative dependability analysis. This method, although with some limitation and drawback offer still convenient visual formal method of describing system behavior on different levels (functional, timing, random events) and offers straight correspondence to underlying mathematical engine, perfect for simulations and engineering support.

In the paper, the solution dedicated for FPGA devices of a synthesis of parallel multiplication systems with the alternative approach, called mutual exclusion, for results of partial products is presented. There are proposed a reducer with the factor 4:2 for parallel multipliers, based on Wallace tree structures, that are dedicated for 4-input and 1-output Look-Up Table (LUT) function generator used in FPGA devices. The elaboration refers to the solution for multiplying using FPGAs the numbers of 4 and 8 bits. However it can be enlarged up to 16 and 32 bits. The proposed solution gives the opportunity to use the probability of conditional significant partial products and faster service - fewer logic levels for special cases of multiplication related to the specific values of the sums of partial product bits.

The paper discusses the possibility of application of nonlinearity measures – INL and DNL, as recommended in IEEE Std 1241, to adaptive cyclic ADC. The first difficulty confronted was not knowing the nominal transfer function of adaptive ADC. To overcome this difficulty, there was proposed an algorithm for its analytical determination on the basis of the models and parameters of the components of the analog part of the converter and of the codes computing algorithm. Using this tool, validated in simulation experiments, there was established a non-uniformity of the adaptive ADC nominal transfer function, concerning both thresholds and quantization levels. The latter is the second, unremovable obstacle to application of INL and DNL measures to characterization of adaptive ADC nonlinearity. In the paper, there are explained the causes of the non-uniformity and there is shown a possibility and conditions of realization of adaptive ADCs with uniform nominal transfer function. Finally, there are presented the results of simulation analysis of the influence of the established non-uniformity of nominal transfer function of adaptive ADC on THD - another popular measure of ADC nonlinearity recommended in IEEE Std 1241 - which show that the non-uniformity does not worsen THD compared with THD obtained for adaptive ADC with similar but uniform transfer function.

This paper describes firmware architecture of a new part of muon trigger system of the CMS detector – one of four detectors installed along LHC accelerator in CERN. Overlap Muon Track Finder (OMTF) is a new trigger subsystem designed to work in difficult barrel-endcap region of CMS detector. OMTF is designed to receive data from different detector types and process it to select 3 best muon candidates. These muon candidates are then forwarded to Global Muon Trigger (GMT). Performance requirements demanded usage of custom designed hardware. All the data reception and processing takes part in modern, large FPGA device. The IPBus module allows easy firmware control and diagnostics via Ethernet connection.