2013 - Repozytorium publikacji - Politechnika Gdańska

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Scaling of signed residue numbers with mixed-radix conversion in FPGA with extended scaling factor selection
- Robert Smyk
- Maciej Czyżak
- Zenon Ulman
2013
A scaling technique of signed residue numbers in FPGA is proposed. The technique is based on conversion of residue numbers to the Mixed-Radix System (MRS). The scaling factor is assumed to be a moduli product from the Residue Number System (RNS) base. Scaling is performed by scaling of MRS terms, the subsequent generation of residue representations of scaled terms, binary addition of these representations and generation of residues for all moduli. The sign of the residue number is detected by using the most significant digit of the MRS representation. Basic blocks of the scaler are realized in the form of modified two-operand modulo adders with included additional multiply and modulo reduction operations. An exemplary pipelined realization of the scaler in the Xilinx FPGA environment is shown. The design is based on Look-Up Tables (LUT)(26 x 1) that simulate small RAMs which serve as main components for the look-up realization. Also a method is shown that allows for flexible selection of scaling factors from a set of moduli products of the RNS base. This is made by forming auxiliary MRSs by permutation of moduli of the base. All formed MRSs are associated with the given RNS with respect to the base but each MRS has different set of weights. Thus for the required scaling factor, the suitable MRS can be chosen that provides for the scaling error smaller than 1.
Scalony regulator o małym spadku napięcia i krótkiej odpowiedzi impulsowej
- Grzegorz Blakiewicz
- Jacek Jakusz
- Waldemar Jendernalik
- Stanisław Szczepański
2013
W artykule zaprezentowano projekt regulatora o małym spadku napięcia. Dzięki zastosowaniu wtórnika napięciowego o małej rezystancji wyjściowej, regulator cechuje się bardzo dobrą odpowiedzią impulsową, a ponadto nie wymaga dodatkowych zewnętrznych kondensatorów kompensujących. W związku z tym, zaproponowany regulator może być całkowicie scalony na podłożu półprzewodnikowym, co jest szczególnie korzystne w systemach realizowanych w formie pojedynczego układu scalonego SoC (ang. system on a chip). W pracy zaprezentowano realizację układową regulatora oraz omówiono ważniejsze etapy procedury projektowania tego układu ze szczególnym uwzględnieniem redukcji czasu odpowiedzi impulsowej. Przedstawiono wyniki symulacji regulatora, zaprojektowanego z użyciem technologii 180 nm CMOS. W opracowanym układzie uzyskano odpowiedź impulsową krótszą niż 1 us oraz skoki napięcie wyjściowego mniejsze niż 42 mV przy zmianie prądu wyjściowego od 100 uA do 100 mA z szybkością 0,3 A/us.
Scene Segmentation Basing on Color and Depth Images for Kinect Sensor
- Adam Brzeski
- Jan Cychnerski
- Adam Blokus
2013
In this paper we propose a method for segmenting single images from Kinect sensor by considering both color and depth information. The algorithm is based on a series of edge detection procedures designed for particular features of the scene objects. RGB and HSV color planes are separately analyzed in the first step with Canny edge detector, resulting in overall color edges mask. In depth images both clear boundaries and smooth depth changes are detected by using Canny detector and Sobel operator. Color and depth information are combined by merging detected edges into single contour mask, being the basis for initial segmentation. The final result is achieved by merging segments of similar depth. The method enables fairly precise scene segmentation with the ability of distinguishing objects of similar color or smooth boundaries.
Schemat zastępczy i charakterystyki elektrodynamiczne mikrofalowego generatora plazmy o strukturze cylindrycznej zasilanego falowodem
- Michał Sobański
- Mariusz Jasiński
- Jerzy Mizeraczyk
2013 Przegląd Elektrotechniczny
W artykule przedstawiono schemat zastępczy oraz charakterystyki elektrodynamiczne mikrofalowego generatora plazmy o strukturze cylindrycznej zasilanego falowodem standardowym WR 430 i pracującym przy częstotliwości 2,45 GHz. Generator ten jest stosowany w laboratorium do produkcji wodoru poprzez reforming węglowodorów.
Schemat zastępczy i charakterystyki elektrodynamiczne mikrofalowego generatora plazmy o strukturze współosiowej zasilanego falowodem
- Michał Sobański
- Mariusz Jasiński
- Jerzy Mizeraczyk
2013 Przegląd Elektrotechniczny
W artykule przedstawiono schemat zastępczy oraz charakterystyki elektrodynamiczne mikrofalowego generatora plazmy o strukturze współosiowej stosowanego w laboratorium do produkcji wodoru. Pomimo tego, że układ zastępczy dotyczy konkretnego generatora plazmy to jednak ma on cechy pozwalające na uogólnione stosowanie w podobnych typach generatorów
Sektorowe zróżnicowanie płynności finansowej przed-siębiorstw
- Piotr Figura
2013 Zarządzanie i Finanse
Płynność finansowa warunkuje prawidłowość funkcjonowania całej firmy. Uzależniona jest od niej możliwość przetrwania przedsiębiorstwa na rynku oraz perspektywa jego rozwoju. Artykuł podejmuje tematykę zróżnicowania płynności finansowej przedsiębiorstw w zależności od ich przynależności sek-torowej. Z przeprowadzonych badań wynika, że wartość wskaźników z obsza-ru płynności finansowej jest silnie zróżnicowana w przekroju sektorowym. Zróżnicowania tego nie eliminuje zalecana w literaturze przedmiotu technika ich korygowania o czynnik czasu. Przeprowadzone badania wykazały ponadto, że menedżerowie najrentowniejszych spółek giełdowych kreują wartości wskaźników z obszaru płynności finansowej na poziomie znacznie odbiegają-cym od zalecanego w literaturze przedmiotu.
SELECTED ASPECTS OF THE EVALUATION OF THE QUALITY OF GRAPE WINE
- Ewa Marjańska
- Elwira Brodnicka
2013
Development of the domestic grape wine market has been presented. The number of grape wine producing entities, acreage, and volume of production over last five years are presented. The composition of red grape wine has been discussed involving health promoting aspects. Two methods of wine quality determination: analytical and sensory meth ods have been described. Physicochemical parameters influencing wine quali ty (acidity, sweetness) and poly phenol and sulphur dioxide content detectable with analytical methods have been defined.
Selected aspects of the evolution of the industry analysis
- Bruno Schivinski
- Radosław Ślosarski
2013
Porter's five forces is a significant tool of analysis of industries. It helps evaluating variables of industry profitability and assessing firm performance. Using the framework, managers can take a decision as to which industries they can effectively compete in and position their companies to reduce the adverse effects of the mentioned forces. According to the critics, the five forces model is limited to its static nature. The enrichment of the model introduced by Brandenburg and Nalebuff took account of the dynamic nature of the competitive environment of industries. According Brandenburg and Nalebuff to the five forces can be extended by adding complementors as an additional competitive force. The incremented model goes beyond Porter's win-lose analysis by cooperation with complementors enlarging the market size.
Selected Features of Dynamic Voting
- Artur Opaliński
2013
In multi-agent systems composed of autonomous agents with local knowledge, it is often desirable to aggregate their knowledge in order to make an educated decision. One of the methods of agreeing to a common decision is voting. A new history-based dynamic weight protocol allows for identification of the agents which contribute to the correct system decision. The main advantage of this approach, compared to static weighted system is that in case the correct agents are not known in advance, they contribution to the system response will grow over time. The system is also able to dynamically track changes in the subset of agents giving correct contribution.
Selected Problems of Cogeneration Energy Systems Designing, Fueled with Landfill Biogas
- Maciej Ziółkowski
2013 Key Engineering Materials
The article discusses the impact of the quality of biogas fuel for operation of generating sets with internal combustion engines. There are presented selected investigation results of landfill biogas fueled gensets operation. The article includes also discussion of the possibility of increasing the efficiency of biogas fuelled cogeneration systems. It also presents guidelines for the optimal design of landfill biogas fueled engines, ensuring their reliability.
Selecting Features with SVM
- Jacek Rzeniewicz
- Julian Szymański
2013
A common problem with feature selection is to establish how many features should be retained at least so that important information is not lost. We describe a method for choosing this number that makes use of Support Vector Machines. The method is based on controlling an angle by which the decision hyperplane is tilt due to feature selection. Experiments were performed on three text datasets generated from a Wikipedia dump. Amount of retained information was estimated by classification accuracy. Even though the method is parametric, we show that, as opposed to other methods, once its parameter is chosen it can be applied to a number of similar problems (e.g. one value can be used for various datasets originating from Wikipedia). For a constant value of the parameter, dimensionality was reduced by from 78% to 90%, depending on the data set. Relative accuracy drop due to feature removal was less than 0.5% in those experiments.
SELECTION OF DIAGNOSTIC FUNCTIONS IN A WHEELED TRACTOR
- Ryszard Arendt
- Ryszard Michalski
2013 Pełny tekst Diagnostyka
In a classical approach to damage diagnosis, the technical condition of an analyzed machine is identified based on the measured symptoms, such as performance, thermal state or vibration parameters. In wheeled tractor the fundamental importance has monitoring and diagnostics during exploitation concerning technical inspection and fault element localizations. The main functions of a diagnostic system are: monitoring tractor components which affect operation, safety, performance parameters and exhaust gas emissions; registering information about component damage; registering performance parameters at the moment of damage. In the paper research problem, methodology and achieved results are presented.
Selection of excitation signals for high-impedance spectroscopy
- Michał Kowalewski
2013 Pełny tekst Journal of Physics : Conference Series
A method of fast impedance spectroscopy of technical objects with high impedance (|Zx| > 1 GOhm) is evaluated in this paper. An object is excited with a signal generated by a digital-to-analog converter (DAC) located on the U2531A DAQ module. Response signals proportional to current flowing through and voltage across the measured object are sampled by analog-to-digital converters (ADC) in the DAQ module. The object impedance spectrum is obtained with use of continuous Fourier transform on the basis of acquired signals. Different excitation signals (square, triangle, sawtooth and sinc) were compared in order to estimate the accuracy of impedance spectrum evaluation. The method is evaluated by means of simulation and practical experiment in a measuring system on an exemplary object in the form of multi-element two-terminal RC network modelling of an anticorrosion coating impedance.
Selection of Relevant Features for Text Classification with K-NN
- Jerzy Balicki
- Henryk Krawczyk
- Łukasz Rymko
- Julian Szymański
2013
In this paper, we describe five features selection techniques used for a text classification. An information gain, independent significance feature test, chi-squared test, odds ratio test, and frequency filtering have been compared according to the text benchmarks based on Wikipedia. For each method we present the results of classification quality obtained on the test datasets using K-NN based approach. A main advantage of evaluated approach is reducing the dimensionality of the vector space that allows to improve effectiveness of classification task. The information gain method, that obtained the best results, has been used for evaluation of features selection and classification scalability. We also provide the results indicating the feature selection is also useful for obtaining the commonsense features for describing natural-made categories.
Selective detection of F- by chromogenic tetrazole receptor
- Agnieszka Pazik
- Anna Skwierawska
2013 SUPRAMOLECULAR CHEMISTRY
A chromogenic anion host 4, containing two amide functionalities linked to azo dye and tetrazole rings was synthesized and its complexes with various anions were investigated. The results show that receptor 4 can recognize selectively biologically important F- ion. The binding affinity for F- was investigated by naked-eye colour change, UV-Vis and 1H NMR spectroscopy. Addition F- ion in CH3CN and DMSO to receptor 4 cause a colour change solution from colorless to yellow. The stoichiometry for host:anion is 1:1. Furthermore, receptor 4 was used as ion carrier in ion-selective membrane electrodes. Selectivity of this membrane was studied toward various anions in water solution. Binding behaviour of receptor 4 towards several anions (Cl-, F-, Br-, I-) have been investigated using density functional theory calculations.
Self-Testing of Analog Parts Terminated by ADCs Based on Multiple Sampling of Time Responses
- Zbigniew Czaja
2013 Pełny tekst IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
A new approach for self-testing of analog parts terminated by analog-to-digital converters in mixed-signal electronic microsystems controlled by microcontrollers is presented. It is based upon a new fault diagnosis method using a transformation of the set of voltage samples of the time response of a tested analog part to a square impulse into localization curves placed in a multidimensional measurement space. The method can be used for fault detection and single soft fault localization. Modified digital Fourier transform formulas are used for conversion of the measurement results to the form used by the fault detection and localization algorithm during the self-testing of the system and also for creation of the fault dictionary. In this paper, the results of experimental verification of the approach are included.
Semantic rules representation in controlled natural language in FluentEditor
- Anna Wróblewska
- Paweł Kapłański
- Paweł Zarzycki
- Iwona Ługowska
2013 IEEE Industrial Electronics Magazine
This paper presents a way of representation of semantic rules (SWRL) in controlled English in order to facilitate understanding the rules by humans interacting with a machine. This approach (implemented in FluentEditor) may be applied in many domains, where the understandability of the rules used to support a decision process is of great importance.
Semantics for an Interdisciplinary Computation
- Justyna Zander
- Pieter J. Mosterman
2013
Semantics for an interdisciplinary computation is becoming increasingly difficult to capture while dealing with multi-domain problems. Expertise from Computer Science, Computer Engineering, Electrical Engineering, and other disciplines merges as engineering challenges in modern systems, such as, Cyber-Physical Systems, Smart Cities, and Bionic Systems must be tackled in a methodological manner. In this paper, a paradigm for formalization of such a computational semantics is proposed. It is based on the experience of a Computer Scientist, Mathematician, and an Engineer when their efforts converge to design a complex system. The design is embedded in the Model-Based Design process and a simulation aids to build the actual system implementation. To let the experts achieve the same understanding level, a declarative layer for simulation semantics is defined. This introduces abstraction and helps understand the behavior of the interacting elements in a system design using mathematical principles that are easier to embrace for more diverse scientific communities.
Sensitivity analysis of simple random beam models by means of Monte Carlo Methods using Variance Reductions Techniques
- Jarosław Górski
- Magdalena Oziębło
- Karol Winkelmann
2013
A probabilistic sensitivity analysis of two nonlinear bar structures is presented. The analysis is carried out on the basis of the Monte Carlo method. The imperfections of the structures and the applied loads are adapted as random variables. Based on all of the generated input variables, an output response of the system is sought. Afterwards, a coefficient responsible for the structure failure is calculated and the limit state histogram is appointed. The shape and the estimators of the histogram make it possible to assess the sensitivity of the selected random variable. This is also performed when the Monte Carlo method variance reductions techniques are applied. The relationship between the behavior of the estimators and the used technique is then observed.
Sensorless induction motor drive with voltage inverter and sine-wave filter
- Jarosław Guziński
- Haitham Abu-Rub
2013
This paper presents a speed sensorless control system of an induction motor with an output LC filter. It is known that the parameters design of the filter gives sine wave motor supply voltage but complicates control and estimation process. The reason is that the voltage drop and phase shift between filter input and output signals are imposed, and hence the motor voltages and currents differ from the inverter output waveforms. To overcome this problem proper control and estimation algorithms have to be modified. The control strategy peoposed in this paper is based on motor feedback linearization control and multiloop control for LC filter whereas the estimator is a modified Luenberger observer with electromotive force calculation. The performance of the system is verified by simulations and experiments.