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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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Computational issues of solving the 1D steady gradually varied flow equation
PublicationIn this paper a problem of multiple solutions of steady gradually varied flow equation in the form of the ordinary differential energy equation is discussed from the viewpoint of its numerical solution. Using the Lipschitz theorem dealing with the uniqueness of solution of an initial value problem for the ordinary differential equation it was shown that the steady gradually varied flow equation can have more than one solution....
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Algorithms for testing security in graphs
PublicationIn this paper we propose new algorithmic methods giving with the high probability the correct answer to the decision problem of security in graphs. For a given graph G and a subset S of a vertex set of G we have to decide whether S is secure, i.e. every subset X of S fulfils the condition: |N[X] \cap S| >= |N[X] \ S|, where N[X] is a closed neighbourhood of X in graph G. We constructed a polynomial time property pseudotester based...
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Ultrashort Opposite Directed Pulses Dynamics with Kerr Effect and Polarization Account
PublicationWe present the application of projection operator methods to solving the problem of the propagation and interaction of short optical pulses of different polarizations and directions in a nonlinear dispersive medium. We restrict ourselves by the caseof one-dimensional theory, taking into account material dispersion and Kerr nonlinearity. The construction of operators is delivered in two variants: for the Cauchy problem and for the...
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Comparison of reproduction strategies in genetic algorithm approach to graph searching
Publicationgenetic algorithms (ga) are a well-known tool used to obtain approximate solutions to optimization problems. successful application of genetic algorithm in solving given problem is largely dependant on selecting appropriate genetic operators. selection, mutation and crossover techniques play a fundamental role in both time needed to obtain results and their accuracy. in this paper we focus on applying genetic algorithms in calculating...
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Analogue GPS repeater
PublicationThis article concerns the problem of difficulty in correct indoor Global Positioning System (GPS) signals reception due to attenuation. Radio signal repeaters are proposed as means to solve this problem. Firstly, the GPS signal characteristics are described, emphasizing their low power in the point of reception. In the second part, various applications of GPS signal repeater, where indoor GPS signals reception is required, are...
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Multi-Aspect Quality Assessment Of Mobile Image Classifiers For Companion Applications In The Publishing Sector
PublicationThe paper presents the problem of quality assessment of image classifiers used in mobile phones for complimentary companion applications. The advantages of using this kind of applications have been described and a Narrator on Demand (NoD) functionality has been described as one of the examples, where the application plays an audio file related to a book page that is physically in front of the phone's camera. For such a NoD application,...
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Adaptation of Architectural Heritage in the Era of Climate Change. Torpedo Platform in Babie Doły
PublicationThe paper provides original insight into the problem of adap¬tation of historical objects in the era of climate change. It conveys a message that in times of climate crisis, there is a need to go beyond an anthropocentric perspective, specifically, that architec¬ture should not only be designed for people, but should also provide a framework for nature. As well as shaping spaces for human beings, the architect is also responsible...
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Designing of Parking Spaces on Parking Taking into Account the Parameters of Design Vehicles
PublicationNowadays, in all cities, there is an acute problem of a lack of parking spaces. The number of vehicles is constantly increasing not only in big cities and megacities, but also in small towns of the country, and there are not enough parking places—the pace of solving the problem is several times slower than the growth rate of transport among citizens. The paper is dedicated to the determination of an optimal size of a parking place...
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Diffusion equations with spatially dependent coefficients and fractal Cauer-type networks
PublicationIn this article, we formulate and solve the representation problem for diffusion equations: giving a discretization of the Laplace transform of a diffusion equation under a space discretization over a space scale determined by an increment h > 0, can we construct a continuous in h family of Cauer ladder networks whose constitutive equations match for all h > 0 the discretization. It is proved that for a finite differences discretization...
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Power efficient thrust allocation algorithms in design of dynamically positioned ships
PublicationAssessment of power consumption on a Dynamically Positioned (DP) ship in the early design stage can assist crucial design choices. The study presents a comparison between two algorithms of optimal thrust allocation in a propulsion system for an over-actuated DP ship. Applied algorithms were Quadratic Programming (QP) and Non- dominated Sorting Genetic Algorithm II (NSGAII). Based on both approaches, tools were developed for ship...
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Measurements of the Hydraulic Fluids Compressibility
PublicationPerformance of the hydrostatic high-pressure drive systems is affected by the changes of working fluid’s volume. Presence of air bubbles in the fluid cause this problem to be even more serious. To study this phenomenon precise measurements of fluid’s bulk modulus are necessary. Differ-ent measurement methods are applied, but they are either limited to low pressure range or give inaccurate results. To solve the problem the new...
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Laplace domain BEM for anisotropic transient elastodynamics
PublicationIn this paper, we describe Laplace domain boundary element method (BEM) for transient dynamic problems of three-dimensional finite homogeneous anisotropic linearly elastic solids. The employed boundary integral equations for displacements are regularized using the static traction fundamental solution. Modified integral expressions for the dynamic parts of anisotropic fundamental solutions and their first derivatives are obtained....
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Negative result about the construction of genuinely entangled subspaces from unextendible product bases
PublicationUnextendible product bases (UPBs) provide a versatile tool with various applications across different areas of quantum information theory. Their comprehensive characterization is thus of great importance and has been a subject of vital interest for over two decades now. An open question asks about the existence of UPBs, which are genuinely unextendible, i.e., they are not extendible even with biproduct vectors. In other words,...
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Emotion Recognition Using Physiological Signals
PublicationIn this paper the problem of emotion recognition using physiological signals is presented. Firstly the problems with acquisition of physiological signals related to specific human emotions are described. It is not a trivial problem to elicit real emotions and to choose stimuli that always, and for all people, elicit the same emotion. Also different kinds of physiological signals for emotion recognition are considered. A set of...
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Application of regularized Savitzky–Golay filters to identification of time-varying systems
PublicationSavitzky–Golay (SG) filtering is a classical signal smoothing technique based on the local least squares approximation of the analyzed signal by a linear combination of known functions of time (originally — powers of time, which corresponds to polynomial approximation). It is shown that the regularized version of the SG algorithm can be successfully applied to identification of time-varying finite impulse response (FIR) systems....
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Relativistic two-dimensional hydrogen-like atom in a weak magnetic field
PublicationA two-dimensional (2D) hydrogen-like atom with a relativistic Dirac electron, placed in a weak, static, uniform magnetic field perpendicular to the atomic plane, is considered. Closed forms of the first- and second-order Zeeman corrections to energy levels are calculated analytically, within the framework of the Rayleigh–Schrödinger perturbation theory, for an arbitrary electronic bound state. The second-order calculations are...
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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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Restricted open shop scheduling
PublicationIn the real applications the open shop scheduling models often require some additional constraints and adequate models. We concern the restrictions in the open shop scheduling related to an instance of the problem and to a feasible solution. Precisely, we require that each jobs consists of the bounded number of operations and each machine has a bounded load (i.e., the total number of operations executed on this machine in a schedule)....
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A fair distribution scheme for joint fingerprinting and decryption methods= Sprawiedliwy schemat dystrybucji dla metod łącznego osadzania odcisku palca oraz deszyfracji
PublicationThe paper addresses the fairness of the security provided by digital fingerprinting methods. It was noted that the digital fingerprinting techniques are designed primarily to protect service providers against the actions of malicious users, while honest users remain vulnerable to acts of malicious providers. The paper describes the customer's rights problem and the unbinding problem, which also apply to joint fingerprinting and...
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Evolutionary Sets of Safe Ship Trajectories: improving the method by adjusting evolutionary techniques and parameters
PublicationThe paper presents some of the evolutionary techniques used by the evolutionary sets of safe ship trajectories method. In general, this method utilizes a customized evolutionary algorithm to solve a constrained optimization problem. This problem is defined as finding a set of cooperating trajectories (here the set is an evolutionary individual) of all the ships involved in the encounter situation. The resulting trajectories are...
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Parametric impulsive noise detector for corrupted audio signals based on hidden Markow model
PublicationThe paper addresses the problem of impulsive noise detection for audio signals. A structure of threshold parameter detectors using modelingof signals was introduced. the algorithm of the noise detection, based on discrete-time hidden Markow model (HMM)of whitened audio signal is elaborated
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An efficient algorithm for mobile guarded guards in simple grids
PublicationW pracy rozważono problem strzeżenia ortogonalnych krat dwuwymiarowych przez mobilne straże strzeżone. Podano algorytmy wielomianowe m.in. dla przypadku krat prostych i dla przypadku krat bez przeszkód w kierunku poziomym (pionowym).
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Badania udarowe uziemień słupów linii elektroenergetycznych
PublicationOmówiono problem badania uziemień słupów linii elektroenergetycznych z uwzględnieniem wpływu słupów sąsiednich oraz fendamentu słupa badanego na wynik pomiaru. Określono procedury pomiarów uziemień słupów linii elektroenergetycznych przy pomocy metod udarowych.
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Bezpieczeństwo infrastruktury szynowej na bocznicach kolejowych
PublicationW referacie przedstawiony został problem bezpieczeństwa infrastrukturyszynowej na przykładzie bocznicy kolejowej. Omówiono zasady bezpiecznego użytkowania budowli przeznaczonych do ruchu kolejowego, zasady uzyskania świadectwa dopuszczenia do eksploatacji oraz prowadzenia prób eksploatacyjnych.
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Synthesis of coupled lossy resonator filters.
PublicationA technique for fast synthesis of coupling matrix low-pass prototypes of generalized. Chebyshev bandpass filters with lossy resonators is presented in this letter. The coupling matrix is found by solving a nonlinear least squares problem based on zeros and poles of filter's transfer functions.
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On delay differential equations with nonlinear boundary conditions
PublicationStosując metodę iteracji monotonicznych podano warunki dostateczne na istnienie kwazirozwiązań lub ekstremalnych rozwiązań rozpatrywanego zagadnienia. Problem jednoznaczności rozwiązania był również przedmiotem badań. Zajmowano się również nierównościami różniczkowymi z opóżnionymi argumentami.
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Dbajmy o poprawność językową naszych prac i wypowiedzi
PublicationCelem opracowania jest zwrócenie uwagi czytelnika na problem braku dbałościo język polski oraz stosowanie poprawnej nomenklatury i terminologii chemi-cznej. W pracy zawarto najczęstsze przypadki usterek terminologicznych iprzejawy żargonu laboratoryjnego.
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Metody i standardy pozycjonowania terminali w systemach komórkowych
PublicationW artykule przedstawiono problem wyznaczania położenia terminala ruchomego w systemach komórkowych. Przedstawiono wybrane metody oraz na podstawie systemu GSM i UMTS przedstawiono obowiązujące standardy lokalizowania terminala ruchomego w sieciach komórkowych.
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Zagadnienie lokalizowania terminala ruchomego w sieciach komórkowych
PublicationW referacje przedstawiono problem wyznaczania położenia terminala ruchomego w systemach komórkowych. Opisano wybrane metody oraz na podstawie systemu GSM i UMTS zaprezentowano obowiązujące standardy lokalizowania terminala ruchomego w sieciach komórkowych.
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O kanalizacyjnej studzience rewizyjnej cz. II
PublicationMonolityczność rozwiązań. Problem wyboru beton czy żelbet. Wymagania w stosunku do betonu, aktualne normy. Zasady montażu. Studzienki kompozytowe, metalowe, z tworzyw termoplastycznych. Szczególne cechy w aspekcie współpracy z podłożem gruntowym.
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Marine autonomous surface ship - control system configuration
PublicationThis paper addresses the problem of marine autonomous surface ship (MASS) control. The contribution of the paper is the development of a control system configuration, done assuming fully autonomous MASS operation under distinct operational conditions. The overview of hardware and software selection is included.
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Selected problems of earth fault loop impedance testing in circuits fed from UPS
PublicationIn the paper a principle of earth fault loop impedance testing in low voltage systems has been presented. Selected factors, influencing accuracy of the testing, are indicated. A structure of UPS of VFI-type and the problem of impedance testing in circuits with such type of UPS are discussed.
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Positive solutions of three-point boundary value problems for second order impulsive differential equations with advanced arguments
PublicationW pracy dyskutowano problem istnienia dodatnich rozwiązań dla równań różniczkowych z impulsami rzędu drugiego i z argumentami typu wyprzedzonego. Podano warunki dostateczne na istnienie jednego lub dwóch rozwiązań dodatnich takich zagadnień.
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Promocja miasta poprzez wykorzystanie wielofunkcyjnych możliwości placów miejskich
PublicationW artykule przedstawiono problem adaptacji współczesnych placów miejskich do potrzeb szybko zmieniającego się rynku, z wykorzystaniem tradycji miejsca oraz funkcji jakim są m.in. targi, jarmarki jak i różnego rodzaju imprezy kulturalne.
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The Complexity of Zero-Visibility Cops and Robber
PublicationIn this work we deal with the computational complexity aspects of the zero-visibility Cops and Robber game. We provide an algorithm that computes the zero-visibility copnumber of a tree in linear time and show that the corresponding decision problem is NP-complete even for the class of starlike graphs.
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Text classifiers for automatic articles categorization
PublicationThe article concerns the problem of automatic classification of textual content. We present selected methods for generation of documents representation and we evaluate them in classification tasks. The experiments have been performed on Wikipedia articles classified automatically to their categories made by Wikipedia editors.
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Organizacja bezpiecznej drogi do szkoły
PublicationProblem bezpiecznej drogi ''dom-szkoła-dom'' najczęściej dotyczy dzieci w wieku od 5 do 15 lat. W referacie omówiono m.in. planowanie bezpiecznej drogi do szkoły, przedstawiono charakterystykę projektu pilotażowego P-1.
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Protection system against electromagnetic leak of information
PublicationW pracy omówiono problem zabezpieczenia przed ulotem elektromagnetycznym informacji. Scharakteryzowano obowiązujace w tym względzie wybrane dokumenty normatywne. Opisano stosowane sposoby zapobiegania ulotowi informacji oraz prezentowano metodykę badawczą. Przedstawiono wybrane wyniki pomiarowe.
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Application capabilities of the maximum distributed generation estimate methodology
PublicationThe paper presents application capabilities of the maximum distributed generation estimate methodology. This subject is an example of solutions to the problem that today face the transmission system operator and distribution system operators, which is related to the high saturation with wind power generation predicted for the near future.
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Niektóre przyczyny awarii kanalizacyjnych studzienek rewizyjnych (3). Odciążenie studzienki
PublicationProblem szczególnych wymagań posadowienia konstrukcji pozbawionych zdolności przenoszenia dużych obciążeń skupionych. Celowość stosowania odciążenia dla różnych konstrukcji (wariantów materiałowych). Specyfika posadowienia pierścienia (płyty) odciążającego. Współpraca z podłożem. Błędy projektu i montażu,.
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Protection of Earthing Reactor Connected to the Star Point of a High Voltage Shunt Reactor
PublicationThe article presents the problem of protection of earthing reactors connected to the star point of shunt reactors in high voltage lines, with particular regard to the detection of internal faults. Model analyses for an actual system commissioned in 2015, which is intended to be provided with earthing reactors, are included.
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System zaopatrzenia w wodę i odprowadzania ścieków na obszarach o niskiej intensywności użytkowania
PublicationSzczególne problemy infrastruktury wodociągowej i kanalizacyjnej na obszarach o niskiej intensywności użytkowania. Problem przewymiarowania - konsekwencje finansowe i techniczne. Zagrożenia sanitarne. Niska jakość całego procesu inwestycyjnego. Błędy, koszty, ceny. Poszukiwanie bezpiecznego rozwiązania.
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Distributed graph searching with a sense of direction
PublicationIn this work we consider the edge searching problem for vertex-weighted graphs with arbitrarily fast and invisible fugitive. The weight function w provides for each vertex v the minimum number of searchers required to guard v, i.e., the fugitive may not pass through v without being detected only if at least w(v) searchers are present at v. This problem is a generalization of the classical edge searching problem, in which one has...
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Rendezvous of Distance-Aware Mobile Agents in Unknown Graphs
PublicationWe study the problem of rendezvous of two mobile agents starting at distinct locations in an unknown graph. The agents have distinct labels and walk in synchronous steps. However the graph is unlabelled and the agents have no means of marking the nodes of the graph and cannot communicate with or see each other until they meet at a node. When the graph is very large we want the time to rendezvous to be independent of the graph size...
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Taking advantage of symmetries: Gathering of many asynchronous oblivious robots on a ring
PublicationOne of the recently considered models of robot-based computing makes use of identical, memoryless mobile units placed in nodes of an anonymous graph. The robots operate in Look-Compute-Move cycles; in one cycle, a robot takes a snapshot of the current configuration (Look), takes a decision whether to stay idle or to move to one of the nodes adjacent to its current position (Compute), and in the latter case makes an instantaneous...
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Dynamic coloring of graphs
PublicationDynamics is an inherent feature of many real life systems so it is natural to define and investigate the properties of models that reflect their dynamic nature. Dynamic graph colorings can be naturally applied in system modeling, e.g. for scheduling threads of parallel programs, time sharing in wireless networks, session scheduling in high-speed LAN's, channel assignment in WDM optical networks as well as traffic scheduling. In...
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Decision support system for design of long distance heat transportation system
PublicationDistrict Heating (DH) systems are commonly supplied using local heat sources. Nowadays, modern insulation materials allow for effective and economically viable heat transportation over long distances (over 20 km). The paper proposes a Decision Support System (DSS) for optimized selection of design and operating parameters of a long distance Heat Transportation System (HTS). The method allows for evaluation of feasibility and effectiveness...
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Distributed Evacuation in Graphs with Multiple Exits
PublicationWe consider the problem of efficient evacuation using multiple exits. We formulate this problem as a discrete problem on graphs where mobile agents located in distinct nodes of a given graph must quickly reach one of multiple possible exit nodes, while avoiding congestion and bottlenecks. Each node of the graph has the capacity of holding at most one agent at each time step. Thus, the agents must choose their movements strategy...
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Modelowanie asymetrycznego procesu walcowania blach bimetalowych = The modeling of asymetrical rolling process of bimetallic plate
PublicationW pracy rozważano problem płynięcia plastycznego bimetalowego pasma podczas asymetrycznego procesu walcowania blach bimetalowych. Asymetrię procesu uzyskano w wyniku wprowadzenia różnic w wartościach sił tarcia na powierzchniach styku pasma z poszczególnymi walcami.