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Search results for: TRANSMISSION QUALITY
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A New Quaternion Encryption Scheme for Image Transmission
PublicationQuaternions are hypercomplex number of rank 4. They are often applied to mechanics in three-dimensional space and considered as one of the best ways to represent rotations. In this paper a new encryption scheme, based on the rotation of data vector in three-dimensional space around another quaternion (key) is proposed. A computer-based simulation was created to analyze the potential of the proposed encryption technique.
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The methods of secure data transmission in the KNX system
PublicationThe article presents the demands concerning data security in distributed building automation systems and shows the need for providing mechanisms of secure communication in the KNX system. Three different methods developed for KNX data protection are discussed: EIBsec, KNX Data Security and the author's method. Their properties are compared and potential areas of application are presented.
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Transmission of digital signals in a nonstationary hydroacoustic channel.
PublicationZ telekomunikacyjnego punktu widzenia właściwości transmisyjne kanału hydroakustyczny są ograniczone przez występowanie wielokrotnych odbić fali dźwiękowej od dna i powierzchni wody oraz niestacjonarność wprowadzaną głównie przez ruch powierzchni wody. Artykuł przedstawia model własności transmisyjnych kanału. Wprowadzono niestacjonarność do odpowiedzi impulsowych kanału przez założenie przypadkowej zmienności czasów przyjścia...
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Structural Health Monitoring of Overhead Power Transmission Lines
PublicationStructural Health Monitoring (SHM) is a novel and continuously developing branch of science and technology that draws attention of scientists all over the world. It creates opportunities to detect, localize and identify structural damage of various types such as: line breakage, permissible sag, bolt loosening, fatigue cracking or insulator contamination. On the other hand the methods used to estimate the remaining operational...
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Establishment of the Right of Electricity Transmission Easement Through Court Proceedings
PublicationIncluding the amendment of the Civil Code Act on May 30, 2008, issues related to the right of easement of transmission were introduced to it. Such a regulation was necessary in view of the need to define the legal status of transmission facilities, existing and designed on real estate property. The purpose of the study is to analyze issues related to the definition of the spatial extent of the law of transmission easement for power...
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The Issues of Reactive Power Compensation in High-voltage Transmission Lines
PublicationThis paper discusses the selection of compensation shunt reactors for a double-circuit 400 kV transmission line using the example of the newly built Elk Bis – Alytus transmission line. The analysis takes into account various conditions of the power system. The published results relate to voltage levels in steady states and during switching processes and short circuits.
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Simulation of Signal Propagation Along Fractional-Order Transmission Lines
PublicationIn this paper, the simulation method of signal propagation along fractional-order (FO) transmission lines is presented. Initially, fractional calculus and the model of FO transmission line are introduced. Then, the algorithm allowing for simulation of the nonmonochromatic wave propagation along FO transmission lines is presented. It employs computations in the frequency domain, i.e., an analytical excitation is transformed to the...
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MEASUREMENT AND ANALYSIS OF TRANSMISSION LOSSES IN THE SUPPLY SYSTEM OF ELECTRIFIED TRANSPORT
PublicationThe issue of electric energy saving in public transport is currently becoming a key area of interest, a fact connected with both an increase in society’s environmental awareness and a rise in the prices of fuel and electricity. Electricity can be saved by reducing transmission losses in the supply system. The article presents a method of measurement and analysis of transmission losses in the supply system of electrified public transport...
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Study of QoS Parameters Measurement Methodology and Requirements in RSMAD
PublicationThe paper presents the results of analysis and research of the quality of service requirements (defined by the QoS parameters) for data transmission services in Radio System for Monitoring and Acquisition of Data from Traffic Enforcement Cameras (in short: RSMAD). The paper also presents and discusses the results of test of impact of the size of images from traffic enforcement cameras (TECs) on the average transmission time. Moreover,...
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Testing OFDM Transmission Schemes for Shallow Water Acoustic Communications
PublicationLarge variability of communication properties of underwater acoustic channels, and especially strongly varying instantaneous conditions in shallow waters, is a tough challenge for the designers of underwater acoustics communication (UAC system. There is a need for developing adaptive signaling schemes that would dynamically optimize signal parameters in both physical and link layers of communication protocols. The orthogonal frequency...
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Transmission protocol simulation framework for the resource-constrained sensor network
PublicationIn this paper the simulation framework for simulation of the sensor network protocol is presented. The framework enables the simultaneous development of the sensor network software and the protocol for the wireless data transmission. The advantage of using the framework is the convergence of the simulation with the real software, because the same software is used in real sensor network nodes and in the simulation framework. The...
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Comparison of experimental results with simulation studies of "digital" hydrostatic transmission
PublicationThe publication presents the results of experimental research on a "digital" hydrostatic transmission conducted at INOE 2000 IHP within the framework of the grant "Method of effective use of the digital hydraulics concept in multi-source hydrostatic drive systems". The primary goal of the research is to compare the effectiveness (efficiency) of using different methods of controlling the pump capacity and the hydraulic motor capacity...
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Approximate models and parameter analysis of the flow process in transmission pipelines
Publicationthe paper deals with the problem of early leak detection in transmission pipelines. First we present the derivation of state-space equations of the flow process in the pipelines. This description is then aggregated in order to obtain a principal model. Next, the problem of process model parameterization is addressed, taking into account the maximization of a model stability margin. The location of the maximum is determined using...
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Quaternion encryption methods for multimedia transmission, a survey of existing approaches
PublicationIn this paper we review quaternion encryption methods for multimedia transmission. We explain their weak and strong properties as well as suggest possible modifications. Our main focus is an algorithm QFC presented in paper by Dzwonkowski et al. (2015). All encryption methods, presented in this paper, use special properties of quaternions to perform rotations of data sequences in 3D space. Each method uses a common key generation...
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Transmission and reflection coefficients for damage identification in 1D elements
PublicationW pracy przedstawiono mozliowści wykorzystania współczynnika odbicia i przejścia fali sprężystej w miejscu nieciągłości konstrukcji do identyfikacji jej rodzaju
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A New Approach For High Speed Data Transmission Monitoring
PublicationW artykule przedstawiono nowatorski sposób monitorowania szybkiej transmisji danych. Technika została zaprezentowana dla przypadku transmisji różnicowej na płycie drukowanej. Cechą szczególną rozwiązania jest możliwość pomiaru jakości transmisji w linii bez konieczności montowania dedykowanych złącz pomiarowych, które mogłyby degradować transmisję.
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Impulse Measurements of Tower Earthings of Overhead Transmission Lines
PublicationPrzepisy wymagają okresowego badania uziemień słupów elektroenergetycznych linii przesyłowych. pomiary takie metodami klasycznymi niskiej częstotliwości wymagają odłączania uziomów od konstrukcji słupa, co wiąże się z wyłączaniem linii. wykorzstanie metody udarowej do oceny uziemień nie wymaga odłączania uziomów i może byc przeprowadzane podczas pracy linii.
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Data transmission optical link for RF-GUN project
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Transmission and Reflection Coefficients for Damage Identification in 1D Elements
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Wave transmission across surface interfaces in lattice structures
PublicationWithin the lattice dynamics formulation, we present an exact solution for anti-plane surface waves in a square lattice strip with a surface row of material particles of two types separated by a linear interface. The considered problem is a discrete analog of an elastic half-space with surface stresses modelled through the simplified Gurtin–Murdoch model, where we have an interfacial line separating areas with different surface...
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Ultrawideband transmission in physical channels: a broadband interference view
PublicationThe superposition of multipath components (MPC) of an emitted wave, formed by reflections from limiting surfaces and obstacles in the propagation area, strongly affects communication signals. In the case of modern wideband systems, the effect should be seen as a broadband counterpart of classical interference which is the cause of fading in narrowband systems. This paper shows that in wideband communications, the time- and frequency-domain...
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Digital Fingerprinting based on Quaternion Encryption for Image Transmission
PublicationIn this paper a new digital fingerprinting scheme for images is proposed. A proposed method is based on quaternion encryption with Cipher Block Chaining (CBC) mode of operation. Quaternions are hyper-complex numbers of rank 4 and thus often applied to mechanics in three-dimensional space. The encryption algorithm is designed for grey-tone images. For purpose of encryption, the algorithm uses the rotation of data vectors presented...
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Wireless data transmission for fiber optical sensor system
PublicationW artykule opisano możliwość wykorzystania bezprzewodowego systemu transmisji danych do transmisji sygnałów z czujników światłowodowych.
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A quaternion-based modified feistel cipher for multimedia transmission
PublicationIn this paper a quaternion-based modified Feistel Cipher is proposed. The algorithm is based on the scheme proposed by Sastry and Kumar (2012). Our algorithm uses special properties of quaternions to perform rotations of data sequences in 3D space for each of the cipher rounds. The plaintext (image in gray-tone) is divided into two square matrices of equal size which consist of Lipschitz quaternions. A modular arithmetic was implemented...
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Influence of the thermal modernization of window on transmission heat losses
PublicationThe article presents the results of calculations of the heat transfer coefficient for the state before and after renovation for the historic windows. The aim of the analysis was to obtain the values of thermal insulation parameters demanded by the regulations, while not losing the historical value of the window. The described example of the renovation of the existing window consisted in installing an additional window panel from...
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Numerical Issues and Approximated Models for the Diagnosis of Transmission Pipelines
PublicationThe chapter concerns numerical issues encountered when the pipeline flow process is modeled as a discrete-time state-space model. In particular, issues related to computational complexity and computability are discussed, i.e., simulation feasibility which is connected to the notions of singularity and stability of the model. These properties are critical if a diagnostic system is based on a discrete mathematical model of the flow...
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Testbed analysis of video and VoIP transsmission performance in IEEE 802.11 b/g/n networks
PublicationThe aim of the work is to analyze capabilities and limitations of different implementations of IEEE 802.11 technologies (IEEE 802.11 b/g/n), utilized for both video streaming and VoIP calls directed to mobile devices. Our preliminary research showed that results obtained with currently popular simulation tools can be drastically different than these possible in real-world environment, so, in order to correctly evaluate performance...
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Power and energy measurement problems in transmission line between Poland-Lithuania
PublicationThe paper discusses problem of power and energy metering in double circuit overhead transmission line. Considerations are based on example of transmission line connecting Polish substation Bis Elk and Lithuanian substation Alytus.
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A New Coupler Concept for Contactless High-Speed Data Transmission Monitoring
PublicationThis paper presents a new concept of a couplerthat can be applied to high-speed data transmission contactlessmeasurements. The proposed approach is dedicated for differentialsignal transmission monitoring in microstrip coupled lineson printed circuit boards (PCBs). The coupler, produced on aseparate PCB, is overlayed on the transmission line with thedifferential signal and delivers decoupled differential signal tothe main measurement...
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Distributed measurement system with data transmission secured using XXTEA algorithm
PublicationThe paper deals with wireless data transmission security in the distributed measurement and control system. An overview of cryptographic algorithms was presented paying special attention to the algorithm dedicated to units with low processing power, which is important due to minimization of energy consumption. Measurement modules equipped with simple microcontrollers send data wirelessly to the central unit. The transmission was...
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Transmission Protocol Simulation Framework For The Resource-Constrained Wireless Sensor Network
PublicationIn this paper a prototype framework for simulation of wireless sensor network and its protocols are presented. The framework simulates operation of a sensor network with data transmission, which enables simultaneous development of the sensor network software, its hardware and the protocols for wireless data transmission. An advantage of using the framework is converging simulation with the real software. Instead of creating...
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The contactless method of chip-to-chip high-speed data transmission monitoring
PublicationThis paper presents a technique of decoupling differential signals transmitted in a pair of microstrip lines on a printed circuit board (PCB), using dedicated coupler for high speed data transmission monitoring in chip-to-chip interconnections. The coupler used for signal probing is overlayed on the pair of microstrip lines under test, and provides a signal to the next blocks of the measurement system without disturbing transmission...
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Case study of water vapour transmission properties of EPDM façade membranes
PublicationThis research aimed to investigate the water vapour transmission properties of chosen EPDM membranes applied in façade and window systems under laboratory tests. The applied procedure included in national and international standards utilized for the laboratory tests of water vapour transmission properties of EPDM membrane is described. Two main types (outside and inside types) of EPDM membranes are laboratory tested. The authors...
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Measurements of High-Speed Data Transmission Radio Link for Special Applications
PublicationIn the article measurements of high-speed data transmission radio link for special applications were presented. Build measurement stand, measurement scenario and obtained results were briefly described. All conducted research work took place in real maritime environment.
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A compact microstrip rat-race coupler constituted by nonuniform transmission lines
PublicationIn this work, a step-by-step development of a compact microstrip rat-race coupler (RRC) has been presented and discussed. A high degree of miniaturization has been obtained by substituting six quarter-wavelength uniform atomic building blocks of a RRC by their nonuniform counterparts. The miniaturization procedure has been realized in three progressive steps: (i) the first layout solution of a miniaturized RRC has been acquired...
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The effect of the power transmission of the spindle on the position of the circular saw teeth
PublicationNa dokładność przecinania ma decydujący wpływ położenie ostrzy piły tarczowej. W pracy analizowano przyczyny i błędy połozenia ostrzy piły w stosunku do przedmiotu obrabianego spowodowane odkształceniem wrzeciona wywołanym przez siły skrawania i siły pochodzące od napędu.
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Measurement accuracy evaluation of transmission line earthings by impulse tests
PublicationUziemienia słupów linii energetycznych powinny być sprawdzane okresowo. Pomiary rezystancji takich uziemień przy pomocy metody niskoczęstotliwościowej wymaga wyłaczania linii i odkręcania przewodów odprowadzających od konstrukcji słupa. Metoda udarowa jest znacznie łatwiejsza w tej aplikacji i nie wymaga wyłaczania linii na czas pomiarów. W pracy oszacowano wpływ uziemień sąsiednich słupów na dokładność pomiarów metodą udarową.
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The Methodology of identifying the place to install shunt compensators in the transmission network
PublicationThis methodology of selection and localization of static com- paper presents pensators in wide network. Proposed method is based on analysis of voltage area power profiles in the nodes of the power grid, and designating locations, In Which Voltages ex- cessively tend to change in time. Practical way of modeling the SVC device in PLANS program you Presented, as well as some example results of research.
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Secure transmission of visual image in the VTS system using fingerprinting
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Reduction of Computational Complexity in Simulations of the Flow Process in Transmission Pipelines
PublicationThe paper addresses the problem of computational efficiency of the pipe-flow model used in leak detection and identification systems. Analysis of the model brings attention to its specific structure, where all matrices are sparse. With certain rearrangements, the model can be reduced to a set of equations with tridiagonal matrices. Such equations can be solved using the Thomas algorithm. This method provides almost the same values...
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Square-wave propagation along coupled coplanar transmission line.
PublicationW pracy przedstawiono wyniki modelowania propagacji fali prostokątnej w układzie sprzężonych linii koplanarnych z uziemionym centralnym paskiem. Przeanalizowano napięcia przesłuchów na bliskim i dalekim końcu linii sprzężonych wykazując poprawę zgodności wyników modelowania i eksperymentu przy uwzględnieniu propagacji wielomodowej.
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Selective jamming of OFDM transmission in NB-IoT radio interface
PublicationThe paper presents the concept of smart jamming, which involves selective interference aimed at critical components of the OFDM signal. Research verifying the feasibility of this type of electronic attack are described. A realized testbed for jamming real NB-IoT signals in a downlink is presented. The test results demonstrate the feasibility of realizing selective jamming and its greater effectiveness compared to barrage interference.
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EHV transmission lines wires location on line operation issues - case studies
PublicationTransmission lines towers construction affects the line parameters and influences on its operation in the future. Misguided design of the tower can lead to serious problems such as overvoltages, electric arc extinction difficulties, voltage asymmetry, resonance phenomena or increasing of magnetic field near the line. The paper points out those threats on example of 400 kV double circuit overhead transmission line with shunt reactors....
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ECHOES REDUCTION DURING DIGITAL DATA TRANSMISSION IN HYDROACOUSTIC CHANNEL – LABORATORY EXPERIMENT
PublicationThe possibility of using a hydroacoustic channel for digital data transmission is very limited. This is due to the effect of multipath propagation of the emitted acoustic wave and the damping of the mechanical wave in this medium, which increase with frequency. The first of these phenomena results in inter-symbol interference disturbances in data transmission systems, including even hundreds of symbols. Due to the number of reflections...
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Damage Detection Strategies in Structural Health Monitoring of Overhead Power Transmission System
PublicationOverhead power transmission lines, their supporting towers, insulators and other elements create a highly distributed system that is vulnerable to damage. Typical damage scenarios cover cracking of foundation, breakage of insulators, loosening of rivets, as well as cracking and breakage of lines. Such scenarios may result from various factors: groundings, lightning strikes, floods, earthquakes, aeolian vibrations, conductors galloping,...
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Transmission Losses Spatial Analysis of the Supply System of Electrified Urban Transport Network
PublicationThe paper presents mathematical model TOPSIS which was applied for MCDA benchmark of trolleybus supply system. Moreover, paper presents the novel method of transmission losses analysis in electrified urban transport system. Research work was based on measurements realized in Gdynia trolleybus network.
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Performance of data transmission in UMTS with turbo code about decreased number of states
PublicationIn the paper a structure of turbo encoder and decoder about decreased number of states has been described. The simulation results of transmission performance based on turbo coding without the reduction of the number of iterations for the uplink and downlink of WCDMA/FDD interface have been presented. The SOVA algorithm for turbo decoding has been used. The investigations have been carried out for Outdoor to Indoor & Pedestrian...
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Overview of cooperative communication methods
PublicationThe paper presents issues related to the cooperative communication in wireless networks. Cooperative com-munication involves the use of mobile terminals as relay stations to improve the transmission quality, improve network performance and reduce energy consumption. It is also possible to use several different data transmission standards. The paper presents the methods used to implement cooperative communication. The types of cooperative...
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Assessment of Wooden Beams from Historical Buildings Using Ultrasonic Transmission Tomography
PublicationThe main goal of this study was non-destructive evaluation of wooden elements using ultrasonic waves. The inspection was carried out on wooden beams from a historical object. Elastic wave signals were processed by ultrasonic transmission tomography to obtain imaging of the internal structure of tested elements without disturbing their state and integrity. The focus was on the influence of wood anisotropy on the propagation of ultrasonic...
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Reduction of the Multipath Propagation Effect in a Hydroacoustic Channel Using Filtration in Cepstrum
PublicationDuring data transmission in a hydroacoustic channel, one of the problems is the multipath propagation effect, which leads to a decrease in the transmission parameters and sometimes completely prevents it. Therefore, we have attempted to develop a method, which is based on a recorded hydroacoustic signal, that allows us to recreate the original (generated) signal by eliminating the multipath effect. In our method, we use cepstral...