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Search results for: waly srubowe
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Transmission Quality Measurements in DAB+ Broadcast System
PublicationIn the age of digital media, delivering broadcast content to customers at an acceptable level of quality is one of the most challenging tasks. The most important factor is the efficient use of available resources, including bandwidth. An appropriate way of managing the digital multiplex is essential for both the economic and technical issues. In this paper we describe transmission quality measurements in the DAB+ broadcast system....
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Effects of Xanthan Gum Biopolymer on the Permeability, Odometer, Unconfined Compressive and Triaxial Shear Behavior of a Sand
PublicationBiopolymers, which are microbially induced polymers, can be used as an alternative material to improve engineering performance of soils. In this paper, a laboratory study of 0.075-1.0 mm size sand and biopolymer (i.e., xanthan gum) mixtures with various mix ratios (0%, 0.5%, 1.0%, and 1.5%) was performed. The materials, specimen preparation, and test methods are described, as are the results of a suite of permeability, odometer, unconfined...
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Recovering Sound Produced by Wind Turbine Structures Employing Video Motion Magnification
PublicationThe recordings were made with a fast video camera and with a microphone. Using fast cameras allowed for observation of the micro vibrations of the object structure. Motion-magnified video recordings of wind turbines on a wind farm were made for the purpose of building a damage prediction system. An idea was to use video to recover sound & vibrations in order to obtain a contactless diagnostic method for wind turbines. The recovered signals...
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Local basis function estimators for identification of nonstationary systems
PublicationThe problem of identification of a nonstationary stochastic system is considered and solved using local basis function approximation of system parameter trajectories. Unlike the classical basis function approach, which yields parameter estimates in the entire analysis interval, the proposed new identification procedure is operated in a sliding window mode and provides a sequence of point (rather than interval) estimates. It is...
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Revalorisation of the Szewalski’s concept of the law of varying the last-stage blade retraction in a gas-steam turbine
PublicationThe article presents the implementations of the free vortex law to the blade of the last stage of a gas-steam turbine. First, a thermodynamic analysis was carried out, determining the parameters at the inlet, then the number of stages of the high and low-pressure part of the turbine was constructed, together with the kinematics and velocity vectors for subsequent stages of the axial turbine. The last step of article was to take...
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TECHNOLOGY OF CREATING AND USAGE OF PROECOLOGICAL BLOCK EMPTYSEED
PublicationNowadays, finding natural substitutes for mass-produced materials is one of the main tasks faced by scientists and designers. There is an increasing emphasis on the theme of ecology and the need for sustainability. Variants and methods are sought which will create environmentally friendly materials in a fast, relatively inexpensive and ecological way. The aim of this paper is to present different proposals of natural building materials...
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Statistically efficient smoothing algorithm for time-varying frequency estimation
PublicationThe problem of extraction/elimination of a nonstationary sinusoidal signal from noisy measurements is considered. This problem is usually solved using adaptive notch filtering (ANF) algorithms. It is shown that the accuracy of frequency estimates can be significantly increased if the results obtained from ANF are backward-time filtered by an appropriately designed lowpass filter. The resulting adaptive notch smoothing (ANS) algorithm...
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A conceptual design and numerical analysis of the mixerless urea-SCR system
PublicationIn the present study, an innovative design of the urea-selective catalytic reduction (SCR) system without conventional mixing elements was developed. The aim was to obtain a high degree of urea decomposition, and uniform ammonia distribution at the inlet to the catalyst, while minimising the liquid film deposition and keeping the compact design. The concept of the design was based on creating high turbulences and elongating...
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High temperature corrosion of evaporator tubes with thermal sprayed coatings
PublicationDegradation examinations of outer surface of low-emission steam boiler evaporator tubes are presented in the paper. Metallographic evaluation of scale morphology, its micro sites chemical composition analysis and distribution of elements on cross sections have been performed. Water-wall tubes were exposed in steam boiler for up to two years period. Common tubes made of 16Mo3 steel suffered sulphide and molten salts corrosions....
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Technologie stosowane do otrzymywania tłuszczów smażalniczych.
PublicationPodano technologie, które mają lub mogą mieć zastosowanie do otrzymywania tłuszczów smażalniczych. Są to: heterogeniczne uwodornienie na katalizatorach metalicznych, głównie niklowych, frakcjonowana krystalizacja, mieszanie tłuszczów lub ich przeestryfikowanie. Przedstawiono wybrane oleje pozyskiwane z roślin oleistych poddanych modyfikacji genetycznej składu kwasów tłuszczowych. Omówiono zalety i wady każdej z metod modyfikacji...
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Próby mechaniki pękania asymetrycznych złączy klejonych
PublicationPraca dotyczy badań asymetrycznych złączy klejonych. Technika połączeń adhezyjnych jest obecnie szeroko stosowana w transporcie, szczególnie lotniczym ale również w budownictwie czy medycynie. W większość zastosowań praktycznych za pomocą klejenia łączy się różne materiał, jednak dla tego typu złączy nie ma żadnych norm czy wytycznych przeprowadzania prób. W pracy zaproponowano trzy metody badania złączy asymetrycznych. Dodatkowo...
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Pyrolysis as an alternative for combustion of waste
PublicationProces pirolizy polega na rozkładzie materii organicznej w podwyższonej temperaturze w warunkach beztlenowych, dlatego może być on stosowany jako alternatywa lub uzupełnienie dla procesu spalania. Piroliza pozwala na uzyskanie substancji chemicznych z polimerów naturalnych i syntetycznych. W umiarkowanej temperaturze (300 - 500 ° C), można uzyskać wysokiej wydajności frakcji ciekłej, natomiast wysokie temperatury sprzyjają powstawaniu...
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Badanie wpływu zmian natężenia prądu na spawanie stopu aluminium
PublicationStop aluminium AW-7075 zyskuje coraz większą popularność w zastosowaniach komercyjnych ze względu na jego wyjątkowe właściwości fizyczne i mechaniczne: małą gęstość, wysoką wytrzymałość, udarność i plastyczność, bardzo dużą odporność na zmęczenie i zadowalającą na korozję, łatwą obrabialność i przetwarzalność. Ze względu na te właściwości, stop ten (AlZn5,5MgCu), zwany też FORTAL-em, używany jest dla części narażonych na wysokie...
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Badanie wpływu zmiany składu gazów osłonowych na spawanie metodą MIG stopu aluminium EN AW 7075. Innowacyjne wykorzystanie w wiertnictwie.
PublicationStop aluminium AW-7075 zyskuje coraz większą popularność w zastosowaniach komercyjnych ze względu na jego wyjątkowe właściwości fizyczne i mechaniczne: małą gęstość, wysoką wytrzymałość, udarność i plastyczność, bardzo dużą odporność na zmęczenie i zadowalającą na korozję, łatwą obrabialność i przetwarzalność. Ze względu na te właściwości, stop ten (AlZn5,5MgCu), zwany też FORTAL-em, używany jest dla części narażonych na wysokie...
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Mechanizmy ochrony integralności plików na poziomie monitora maszyny wirtualnej
PublicationMechanizmy ochrony integralności plików umożliwiają wykrywanie nieautoryzowanych zamian w kluczowych do działania systemu operacyjnego plików. Dotychczas rozwiązania tego typu działały jako aplikacje systemowe lub były integrowane z jądrem systemu operacyjnego. Wraz ze zwiększeniem dostępności technik wirtualizacji pojawiła się możliwość przeniesienia systemu ochrony na poziom monitora maszyny wirtualnej, co zapewnia izolację mechanizmu...
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Koncepcja, realizacja i analiza nowego typu silnika piezoelektrycznego o strukturze wielokomórkowej
PublicationDotychczasowe wyniki badań w obszarze aktuatorów piezoelektrycznych, wskazują ich potencjalnie duże możliwości w przyszłych zastosowaniach specjalnych. W artykule przedstawiono proces projektowania nowego typu silnika piezoelektrycznego. Opisane zostały wybrane topologie maszyn piezoelektrycznych. Przedstawiono wady i zalety silnika ultrasonicznego z falą biegnącą oraz silnika o ruchu obrotowym. W ramach realizacji projektu...
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Wykorzystanie pomiarów wyładowań niezupełnych do oceny układu izolacyjnego izolatora przepustowego średniego napięcia do zastosowań technologicznych
PublicationW artykule przedstawiono wyniki badań wyładowań niezupełnych (wnz) w układzie izolacyjnym eksploatowanego izolatora przepustowego średniego napięcia (SN) mierzonych bezpośrednią metodą elektryczną i innymi technikami pomiarowymi wykorzystującymi czujniki pojemnościowe, indukcyjne, elektromagnetyczne oraz metodą chemiczną. Wykorzystane metody pomiarowe umożliwiają nie tylko detekcję wyładowań niezupełnych, ale również umożliwiają...
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Horyzont energoelektroniczny obiektów morskich
PublicationW artykule zaprezentowano współczesne kierunki rozwoju energoelektroniki, w tym w szczególności dotyczące obiektów morskich. Przedstawiono podstawowe parametry aktualnie stosowanych w energoelektronice przyrządów półprzewodnikowych, jak również wykazano interdyscyplinarny charakter rozwoju tej dziedziny. Na przykładzie wybranych urządzeń energoelektronicznych przedstawiono ich komercyjne zastosowania oraz podział i miejsce w łańcuchu...
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Zalety oraz problemy związane z zagospodarowaniem osadów ściekowych metodą systemów trzcinowych
PublicationCiekawą alternatywą dla małych i średnich oczyszczalni ścieków może być metoda wykorzystująca systemy trzcinowe do jednoczesnego odwadniania i stabilizacji osadów. Metoda ta posiada wiele zalet. Przede wszystkim charakteryzuje się niskimi kosztami inwestycyjnymi i eksploatacyjnymi. Dodatkowo osady po przeróbce w systemach trzcinowych mogą zostać wykorzystane przyrodniczo. Należy jednak pamiętać, że metoda ta, jak każda inna, ma...
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Clearing directed subgraphs by mobile agents
PublicationWe study several problems of clearing subgraphs by mobile agents in digraphs. The agents can move only along directed walks of a digraph and, depending on the variant, their initial positions may be pre-specified. In general, for a given subset S of vertices of a digraph D and a positive integer k, the objective is to determine whether there is a subgraph H=(V,A) of D such that (a) S is a subset of V, (b) H is the union of k directed...
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Impact of Geometrical Imperfections on Estimation of Buckling and Limit Loads in a Silo Segment Using the Vibration Correlation Technique
PublicationThe paper examines effectiveness of the vibration correlation technique which allows determining the buckling or limit loads by means of measured natural frequencies of structures. A steel silo segment with a corrugated wall, stiffened with cold-formed channel section columns was analysed. The investigations included numerical analyses of: linear buckling, dynamic eigenvalue and geometrically static non-linear problems. Both perfect...
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LE STIME ECONOMICHE DELLA CIA E L’IMPREVEDIBILE FINE DELL’URSS
PublicationIn this article, we will analyze the debate that took place around the assessments that the CIA gave of the economic situation in the Soviet Union, a clearly decisive key to understanding the overall health of the main political-military opponent of the United States. The article will include the discussions that flared up in the American political establishment starting in 1990, after the fall of the Berlin Wall and the initial...
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Buckling of simplified models of silo with corrugated walls and vertical stiffeners
PublicationThe paper deals with buckling of cylindrical silos composed of corrugated sheets and vertical stiffeners (columns). Comprehensive finite element analyses were carried out for a perfect silo by means of a linear buckling approach. Corrugated walls were simulated as an equivalent orthotropic shell and vertical thin-walled columns as beam elements. Calculations for perfect silos with different numbers of columns made it possible to...
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Geo-engineering computer simulation seems attractive but is it the real world?
PublicationCorrect formulation of the differential equation system for equilibriom conditions of subsoil, especially in terms of controlled numerical calculation, is discussed. The problem of solution stability is also considered. The solution of problems, which are ill-posed, have no practical value in the majority of cases and is this way the engineering prognosis can lead to real disaster. The object of this paper is quite relevant if...
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the assessment of the noise-induced harmful effects based on the properties of human hearing system
PublicationA new way of assessment of noise-induced harmful effects on human hearing system is presented in the paper. The method takes into consideration properties of the human hearing system. The pro-posed method determines the cumulative impact on hearing system produced by the excessive noise. Based on the predicted effects of the noise exposure, the new types of noise indicators were developed. The evaluation of these indicators was...
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The noise-induced harmful effect assessment based on the properties of the human hearing system
PublicationA new way of assessment of noise-induced harmful effects on human hearing system is presented in the paper. The method takes into consideration properties of the human hearing system. The pro-posed method determines the cumulative impact on hearing system produced by the excessive noise. Based on the predicted effects of the noise exposure, the new types of noise indicators were developed. The evaluation of these indicators was...
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A new methodological approach to the noise threat evaluation based on the selected physiological properties of the human hearing system
PublicationA new way of assessment of noise-induced harmful effects on human hearing system is presented in the paper. The method takes into consideration properties of the selected physiological human hearing system. On the basis of the hearing examinations and noise measurements results and psychoacoustical noise dosimeter performance the new indicators of the noise harmfulness were proposed. The evaluation of the proposed indicators were...
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Probabilistic sensitivity of the limit states of structures using Monte Carlom simulation
PublicationThe paper presents the concept of probabilistic sensitivity of structural limit states with respect to given design variables. A general idea is presented, illustrated by a simple case solved in an analytical way. More general approach is presented for the engineering structures, in this case a dedicated Monte Carlo simulation procedure is involved as part of the methodology. Illustration of the engineering case is done, by means...
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Philosophy of Symbolic Forms and a Mystery of “Appearing Itself ”. Cassirer in the Context of Phenomenology
Publicationin the publications concerning Cassirer, whose number has been increasing for about a dozen years, more and more space is devoted to the genesis of his philosophy, and more attention is paid to its linkage to Neo-Kantian Marburg school. Also, in addition to Kantian, Hegelian and Goethean heritage in Cassirer’s philosophy is indicated, while its discovered philosophical foundations make it possible to regard the author of The Philosophy...
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Validation of dynamic electrochemical impedance spectrograms using autocorrelation function
PublicationValidation of impedance data is essential for checking the reliability of experimental data. Kramers – Kronig transformation is used to verify data obtained from classical Electrochemical Impedance Spectroscopy (EIS) measurements. Data obtained from Dynamic Electrochemical Impedance Spectroscopy (DEIS) could be validated in the same way, but in this case, there is no information about internal consistency between every single spectrum...
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Testing A Novel Gesture-Based Mixing Interface
PublicationWith a digital audio workstation, in contrast to the traditional mouse-keyboard computer interface, hand gestures can be used to mix audio with eyes closed. Mixing with a visual representation of audio parameters during experiments led to broadening the panorama and a more intensive use of shelving equalizers. Listening tests proved that the use of hand gestures produces mixes that are aesthetically as good as those obtained using...
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Facial data registration facility for biometric protection of electronic documents
PublicationIn modern world, information is crucial, and its leakage may lead to serious losses. Documents as the main medium of information must be therefore highly protected. Nowadays, the most common way of protecting data is using passwords, however it seems inconvenient to type complex passwords, when it is needed many times a day. For that reason a significant research has been conducted on biometric authentication...
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Polypyrrole based gas sensor for ammonia detection
PublicationThe nature of polypyrrole response to toxic gases does not allow using the sensor in a conventional way. The main aim of this study is to acquire the information about the concentration using different approaches: a linear approximation, a non-linear approximation and a tangent method. In this paper a two-steps procedure for sensor response measurements has been utilized. Polypyrrole films were electrochemically synthesized on...
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Ordinal pattern statistics for the assessment of heart rate variability
PublicationThe recognition of all main features of a healthy heart rhythm (the so-called sinus rhythm) is still one of the biggest challenges in contemporary cardiology. Recently the interesting physiological phenomenon of heart rate asymmetry has been observed. This phenomenon is related to unbalanced contributions of heart rate decelerations and accelerations to heart rate variability. In this paper we apply methods based on the concept...
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Evolutionary Sets of Safe Ship Trajectories: problem dedicated operators
PublicationThe paper presents the optimization process of the evolutionary sets of safe ship trajectories method, with a focus on its problem-dedicated operators. The method utilizes a customized evolutionary algorithm to solve a constrained optimization problem. This problem is defined as finding a set of cooperating trajectories (a set is an evolutionary individual) of all the ships involved in the encounter situation. The resulting trajectories...
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Absorbing Boundary Conditions Derived Based on Pauli Matrices Algebra
PublicationIn this letter, we demonstrate that a set of absorbing boundary conditions (ABCs) for numerical simulations of waves, proposed originally by Engquist and Majda and later generalized by Trefethen and Halpern, can alternatively be derived with the use of Pauli matrices algebra. Hence a novel approach to the derivation of one-way wave equations in electromagnetics is proposed. That is, the classical wave equation can be factorized...
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Hopf bifurcation in time‐delayed gene expression model with dimers
PublicationWe study a mathematical model of gene transcription and protein synthesis with negative feedback. We consider a system of equations taking into account the formation of dimers (i.e., complex formed by two protein monomers), the way in which dimers bind to DNA and time delay in translation process. For the model consisting of three ordinary differential equations with time delay, we derive conditions for stability of the positive...
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Annihilation rates of low-energy positron scattering from simple diatomic molecules
PublicationWe discuss the calculations of Zeff coefficients for a series of diatomic molecules over the range of energies below the positronium formation. During the development of a general code for polyatomic, nonlinear molecules colliding with positrons, it was discovered that the earlier one, employed only for diatomic molecules, had an error. The error is corrected and the corrected results are presented here. We also discuss a way of...
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Improving all-reduce collective operations for imbalanced process arrival patterns
PublicationTwo new algorithms for the all-reduce operation optimized for imbalanced process arrival patterns (PAPs) are presented: (1) sorted linear tree, (2) pre-reduced ring as well as a new way of online PAP detection, including process arrival time estimations, and their distribution between cooperating processes was introduced. The idea, pseudo-code, implementation details, benchmark for performance evaluation and a real case example...
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The entrepreneurship of host cities of the Olympic Games – Between success and social destruction
PublicationMany publications focus on the deficit nature of the Olympic Games organisation, when considered from the point of view of host cities – organisers of such events. However, does such an event actually affect the region and the host country in a positive way? The presented article aims at the assessment of the organisation of mass sports events, such as the Olympic Games, taking into consideration entrepreneurial activities which...
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Gaseous products from scrap tires pyrolisis
PublicationIn European Union 75% of used tires should be recycled. The most common method of used tires disposal, is burning in cement kilns, which does not solve the problem. Pyrolysis process can be an alternative way of utilization of tires. The aim of the researches was to check the influence of pyrolysis products (gas and oil fractions) on environment. Samples from pyrolysis process, like light oil fractions or pyrolysis gases were analyzed...
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The project of pull system for storehouse and production line in a company provides electronics
PublicationThe chapter below presents how to reduced delivery of the material to production by using a "Kanban schedule board" and related tools from 48 hours and 59 minutes to 41 minutes in a company provides electronics. The solution was found through analysis of the current way of supplying stands and using Just In Time idea, the reduction of ''muda''. To solve the problem was used Kanban card", which has the shape of two triangles joined...
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Shaping of the turnout diverging track with variable curvature sections
PublicationThe paper presents an analytical method of shaping the turnout diverging railroad track with variable curvature segments on its length, which in an evident way distinguished it from a typical solution, made up of a single circular arc with no transition curves. Two separate causes including a linear and a nonlinear curvature one in the form of a polynomial have been examined. The obtained solutions of the problem have a universal...
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Failure of cold-formed beam: How does residual stress affect stability?
PublicationIn machine industry, stresses are often calculated using simple linear FEM analysis. Occasional failures of elements designed in such a way require recomputation by means of more sophisticated methods, eg. including plasticity and non-linear effects. It usually leads to investigation of failure causes and improvement of an element in order to prevent its unwanted behavior in the future. The study presents the case where both linear...
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Structure and thermoelectric properties of Cs-Bi-Te alloys fabricated by different routes of reduction of oxide reagents
PublicationCesium-bismuth-telluride polycrystalline materials were fabricated using a cost-effective method based on a reduction of oxide reagents, leading to a production of a material with good thermoelectric properties. Several samples with various initial stoichiometry were prepared by melting of oxide powders at 1050 °C, quenching, milling to powders and then reducing in pure hydrogen at 400 °C. Another concept was to obtain the CsBi4Te6...
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The analysis of temperature changes of the saliva traces left on the fur during laboratory rats social contacts
PublicationAutomatic analysis of complex rodent social be- havior, especially aggressive ones, is of important scientific interest. In this paper we analyze the properties of the data created as a result of aggressive rodent social behavior. Detec- tion of specific aggressive behaviors is based on the event of leaving traces of saliva on the fur of the attacked individual, which are clearly visible in the thermal imaging. The traces change...
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When Neural Networks Meet Decisional DNA: A Promising New Perspective for Knowledge Representation and Sharing
PublicationABSTRACT In this article, we introduce a novel concept combining neural network technology and Decisional DNA for knowledge representation and sharing. Instead of using traditional machine learning and knowledge discovery methods, this approach explores the way of knowledge extraction through deep learning processes based on a domain’s past decisional events captured by Decisional DNA. We compare our approach with kNN (k-nearest...
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Optimal Rotating Receiver Angles Estimation for Multicoil Dynamic Wireless Power Transfer
PublicationThis study proposed an approach to dynamic wireless charging that uses a rotating receiver coil. Our simulation study focused on the verification of a novel way of increasing the coupling coefficient and power transfer stability by following the flux of the transmitting coils. To obtain the highest possible coupling by means of the FEM analysis, we studied the optimization of the trajectory of the angular velocity of the rotating...
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Influence of external walls' thermal capacitance on indoor thermal comfort
PublicationThe doctoral thesis presents the results of numerical investigations on the influence of walls’ thermal capacitance on indoor thermal comfort. A proper set of thermal parameters of a building structure can considerably limit the heating / cooling demand, and passively increase the indoor thermal comfort. However the effect of building thermal capacitance on indoor conditions is complex and not always beneficial. Among a great number...
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Wykorzystanie sztucznych sieci neuronowych do szacowania wpływu drgań na budynki jednorodzinne
PublicationW artykule przedstawiono metodę prognozowania wpływu drgań na budynki mieszkalne z wykorzystaniem sztucznych sieci neuronowych. Drgania komunikacyjne mogą doprowadzić do uszkodzenia elementów konstrukcyjnych, a nawet do awarii budynku. Najczęstszym efektem są jednak rysy, pękanie tynku i wypraw. Metody oparte na sztucznej inteligencji są przybliżone, ale stanowią wystarczająco dokładną i ekonomiczną alternatywę dla tradycyjnych...