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Search results for: COMMUNIATION NETWORKS
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Optimal routing in a transportation network
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Automated network control and supervision
PublicationPrzedstawiono ogólne problemy związane z postępem w zakresie integracji systemów informatycznych w elektroenergetyce. Podano zasady budowy struktury systemów sterowania i nadzoru.
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Collision-Free Network Exploration
PublicationA set of mobile agents is placed at different nodes of a n-node network. The agents synchronously move along the network edges in a collision-free way, i.e., in no round may two agents occupy the same node. In each round, an agent may choose to stay at its currently occupied node or to move to one of its neighbors. An agent has no knowledge of the number and initial positions of other agents. We are looking for the shortest possible...
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Collision-free network exploration
PublicationMobile agents start at different nodes of an n-node network. The agents synchronously move along the network edges in a collision-free way, i.e., in no round two agents may occupy the same node. An agent has no knowledge of the number and initial positions of other agents. We are looking for the shortest time required to reach a configuration in which each agent has visited all nodes and returned to its starting location. In...
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Evaluation of the High-Pressure Gas Transmission Network Impact for Environmental - Construction Phase and Network Operation
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Comparison of single best artificial neural network and neural network ensemble in modeling of palladium microextraction
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Journal of Network Theory in Finance
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Social Network Analysis and Mining
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Journal on Chain and Network Science
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Competition and Regulation in Network Industries
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NETWORK-COMPUTATION IN NEURAL SYSTEMS
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Journal of Network and Systems Management
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International Journal of Network Management
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JOURNAL OF NETWORK AND COMPUTER APPLICATIONS
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Information and Communication Technology Management for Global Competitiveness and Economic Growth in Emerging Economies
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Overview of current communication systems for security forces. Features, limitations and potential solutions
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Validation of a virtual test environment for C2X communication under radio jamming conditions
PublicationIn this paper, we propose a novel car-2-x communication security testing methodology in the physical layer of wireless systems. The approach is dedicated to automated testing of autonomous vehicles and it is essential for such complex systems operation, especially with regard to safety and security issues. It is based on scenario-driven testing in virtual and real test environments created from collected or simulated data. The...
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The influence of the development of private air communication on the architecture and urban planning of the 21st century
PublicationIn the first part, the article describes the stages of the development of gyroplanes and the influence of wartime policy on the interest in light aircraft. Also presented are links and the possibilities of using gyroplanes in various sectors of the economy. The authors, based on source texts, present the current position of the aviation industry in the Polish economy and attempt to diagnose its development capabilities. As a result,...
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ADAPTIVE IDENTIFICATION OF TIME-VARYING IMPULSE RESPONSE OF UNDERWATER ACOUSTIC COMMUNICATION CHANNEL
PublicationThe transmission properties of underwater acoustic communication channel can change dynamically due to the movement of acoustic system transmitter and receiver or underwater objects reflecting transmitted signal. The time-varying impulse response measurement and estimation are necessary to match the physical layer of data transmission to instantaneous channel propagation conditions. Using the correlative measurement method, impulse...
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The dynamics of the total outputs of Japanese information and communication technology sectors: A further study
PublicationThe purpose of this study is to continue the previous studies which discussed the impacts of the changes of final demands on the total outputs of the Information and Communication Technology (ICT) sectors of the specific country. More specifically, this study aims to conduct a deeper analysis regarding these impacts. This study focuses on the case of Japan. This study employs a demand-pull Input-Output (IO) quantity model, one...
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Using Fast Frequency Hopping Technique to Improve Reliability of Underwater Communication System
PublicationAcoustic underwater communication systems designed to work reliably in shallow coastal waters must overcome major limitations such as multipath propagation and the Doppler effect. These restrictions are the reason for the complexity of receivers being built, whose task is to decode a symbol on the basis of the received signal. Additional complications are caused by the low propagation speed of the acoustic wave in the water and...
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Communication Model Order Reduction in Hybrid Methods Involving Generalized Impedance Matrix
PublicationA novel strategy for the efficient analysis of frequency-domain scattering electromagnetic problems in open and closed domains is presented. A fully automatic model-order reduction technique, called the enhanced reduced-basis method, is applied to increase the efficiency of the hybrid approach, which combines the finite-element and mode-matching methods. Numerical tests show that the proposed algorithm yields reliable and highly...
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Communication and Documentation Practices in Agile Requirements Engineering: A Survey in Polish Software Industry
PublicationRequirements engineering, system analysis and other analytical activities form the basis of every IT project. Such activities are not clearly defined in Agile development methods, but it does not mean that they are absent in an agile project. The aim of our work was to determine which practices related to requirements-related communication and which requirements documenting techniques are used in agile software projects. For this...
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Validation of a virtual test environment for C2X communication under radio jamming conditions
PublicationIn this paper, we propose a novel car-2-x communication security testing methodology in the physical layer of wireless systems. The approach is dedicated to automated testing of autonomous vehicles and it is essential for such complex systems operation, especially with regard to safety and security issues. It is based on scenario-driven testing in virtual and real test environments created from collected or simulated data. The...
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Karhunen-Loeve-based approach to tracking of rapidly fading wireless communication channels
PublicationWhen parameters of wireless communication channels vary at a fast rate, simple estimation algorithms, such as weighted least squares (WLS) or least mean squares (LMS) algorithms, cannot estimate them with the accuracy needed to secure the reliable operation of the underlying communication systems. In cases like this, the local basis function (LBF) estimation technique can be used instead, significantly increasing the achievable...
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Study on Speech Transmission under Varying QoS Parameters in a OFDM Communication System
PublicationAlthough there has been an outbreak of multiple multimedia platforms worldwide, speech communication is still the most essential and important type of service. With the spoken word we can exchange ideas, provide descriptive information, as well as aid to another person. As the amount of available bandwidth continues to shrink, researchers focus on novel types of transmission, based most often on multi-valued modulations, multiple...
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Underwater acoustic communication system using broadband signal with hyperbolically modulated frequency
PublicationThe implementation of reliable acoustic underwater communication in shallow waters is a scientific and engineering challenge, mainly due to the permanent occurrence of the multipath phenomenon. The article presents the concept of a transmission system using a broadband signal with hyperbolically modulated frequency (HFM) to transmit data symbols and synchronize data frames. The simulation tests were carried out in channels with...
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Inclusive Communication Model Supporting the Employment Cycle of Individuals with Autism Spectrum Disorders
PublicationDifficulties with interpersonal communication experienced by individuals with autism spectrum disorders (ASD) significantly contribute to their underrepresentation in the workforce as well as problems experienced while in employment. Consistently, it is vital to understand how communication within the employment cycle of this group can be improved. This study aims to identify and analyze the possibilities of modifying the communication...
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Implementation Of The Innovative Radiolocalization System VCS-MLAT (Voice Communication System Multilateration)
PublicationIn the article the concept of the radiolocalization subsystem of the VHF communication for aviation VCS-MLAT (Voice Communication System – Multilateration) is presented. The distributed localization system can estimate the position of the aircraft using the audio signals from aircraft transmitters in the VHF band (118-136 MHz). This paper shows initial verification of the possibility to use voice airband communication to estimate...
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Wideband Channel Measurements for Polarised Indoor Off-Body Communications
PublicationThis paper presents the initial results of wideband channel measurements for polarised off-body communication at 5.8 GHz, in an indoor environment. Channel Impulse Response measurements were performed simultaneously for two orthogonal polarisations of the wearable antenna, and repeated for vertical and horizontal orientations of the off-body one. Four types of measurement scenarios were considered in order to investigate the influence...
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System Loss in UWB Off-Body Communications in a Ferry Environment
PublicationIn this paper, the system loss in UWB off-body communications in a ferry environment based on measurements is presented. A mobile measurement set-up, consisting of WBAN nodes with UWB DWM1000 modules, was used. System loss was split into LOS and NLOS conditions. For the former, the smallest mean value, 24.4 dB, was obtained for the user approaching the fixed terminal, with the antenna on his chest, and the largest, 28.1 dB, for...
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Underwater acoustic communications system with error correction and synchronization coding
PublicationNiezawodna transmisja danych w wielodrogowym i niestacjonarnym płytkim kanale podwodnym wymaga zastosowania efektywnej techniki modulacji oraz equalizacji adaptacyjnej. W zaproponowanym artykule w systemie transmisji danych zastosowano modulację OFDM oraz equalizację adaptacyjną opartą o filtrację Kalmana. Ponadto zaimplementowano dwie techniki kodowania: FEC w celu eliminacji błędów transmisji oraz kodowanie pseudoszumowe, którego...
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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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Radio Channel Measurements in Body-to-Body Communications in Different Scenarios
PublicationThis paper presents body-to-body radio channel measurements at the 2.45 GHz band, for different body motion scenarios and on-body antenna placements, and both indoor and outdoor environments. Measurement equipment, investigated scenarios and considered environments are described, an initial analysis of results being presented. The mean path loss and the standard deviation depend on the mutual location of transmitting and receiving...
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Radio Channel Measurements in Body-to-Body Communications in Different Scenarios
PublicationThis paper presents body-to-body radio channel measurements at the 2.45 GHz band, for different body motion scenarios and on-body antenna placements, and both indoor and outdoor environments. Measurement equipment, investigated scenarios and considered environments are described, an initial analysis of results being presented. The mean path loss and the standard deviation depend on the mutual location of transmitting and receiving...
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Evaluation of Connectivity Gaps Impact on TCP Transmissions in Maritime Communications
PublicationMany organizations and research working groups, including among others IEEE, ITU, ETSI and IMO are currently working towards improvements in communication of different types of vehicles (cars, trains, planes and vessels) and upgrading utilities and services offered to their crews and passengers travelling all over the world. The paper deals with selected aspects of the TCP protocol connectivity in maritime wireless networks. The...
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Compact Dual-Polarized Corrugated Horn Antenna for Satellite Communications
PublicationIn this paper, a structure and design procedure of a novel compact dual-polarized corrugated horn antenna with high gain and a stable phase center for satellite communication is presented. The antenna incorporates an Ortho-Mode Transducer (OMT), a mode converter, and a corrugated structure. The compact OMT section is designed to be fed by standard WR-75 waveguides. The proposed compact design utilizes only ten corrugated slots...
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Non-Satellite Broadband Maritime Communications for e-Navigation Services
PublicationThe development of broadband network access technologies available to users on land has triggered a rapid expansion of a diverse range of services provided by terrestrial networks. However, due to limitations of digital communication technologies in the off-shore area, the maritime ICT systems evolution so far has not followed that trend. Despite the e-navigation initiative defining the set of Maritime Services, the progress in...
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Synchronization system for underwater acoustic communications using in shallow waters
PublicationA reliable synchronization system of the transmitted data frame has a significant impact on the efficiency of the underwater communication system. This applies in particular to communication systems dedicated to work in shallow waters, where the phenomenon of multipath permanently occurs. To overcome these difficulties, the concept of a synchronization system consisting of two broadband signals of opposite monotonicity was presented....
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On the Disaster Resiliency within the Context of 5G Networks : The RECODIS Experience
PublicationNetwork communications and the Internet pervade our daily activities so deeply that we strongly depend on the availability and quality of the services they provide. For this reason, natural and technological disasters, by affecting network and service availability, have a potentially huge impact on our daily lives. Ensuring adequate levels of resiliency is hence a key issue that future network paradigms, such as 5G, need to address. This...
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Trade-offs in multiparty Bell-inequality violations in qubit networks
PublicationTwo overlapping bipartite binary input Bell inequalities cannot be simultaneously violated as this would contradict the usual no-signalling principle. This property is known as monogamy of Bell inequality violations and generally Bell monogamy relations refer to trade-offs between simultaneous violations of multiple inequalities. It turns out that multipartite Bell inequalities admit weaker forms of monogamies that allow for violations...
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A MODEL FOR FORECASTING PM10 LEVELS WITH THE USE OF ARTIFICIAL NEURAL NETWORKS
PublicationThis work presents a method of forecasting the level of PM10 with the use of artificial neural networks. Current level of particulate matter and meteorological data was taken into account in the construction of the model (checked the correlation of each variable and the future level of PM10), and unidirectional networks were used to implement it due to their ease of learning. Then, the configuration of the network (built on the...
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Buck-Boost Inverters with Symmetrical Passive Four-terminal Networks
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Protecting Wireless Mesh Networks Against Adverse Weather Conditions
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Using neural networks to examine trending keywords in Inventory Control
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Bin-packing based optimisation of EON Networks with S-BVTs
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Prediction of antimicrobial activity of imidazole derivatives by artificial neural networks
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Forecasting of currency exchange rates using artificial neural networks
PublicationW rozdziale tym autor przedstawił wyniki swoich badań nad wykorzystaniem sztucznych sieci neuronowych do prognozowania kursu walut (na przykładzie pary walutowej PLN-USD).Głównym celem badań było porównanie skuteczności przewidywania kursu złotówki w latach 1997 - 2005 przy pomocy różnych rodzajów sieci neuronowych.
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Performance analysis of co-existing Wi-Fi and Bluetooth networks
PublicationPasmo ISM wykorzystywane jest przez wiele różnych technologii transmisji bezprzewodowej. Tym samym pojawiają się problemy związane z zapewnieniem określonej efektywności dla sieci różnych technologii. W artykule analizowano wpływ wzajemnych interferencji nadajników sieci Bluetooth i IEEE802.11b, badano przykładowe scenariusze pracy oraz przedstawiono wyniki badań dotyczących techniki AFH (ang. Adaptive Frequency Hopping).
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Neural networks based NARX models in nonlinear adaptive control
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