Wyniki wyszukiwania dla: COMMUNICATION PROCESS - MOST Wiedzy

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Wyniki wyszukiwania dla: COMMUNICATION PROCESS

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Wyniki wyszukiwania dla: COMMUNICATION PROCESS

  • Trunked Radio Solutions for Special Application

    In the paper modern concepts of radio communication trunking-dispatch systems for special applications are presented. Basic standards of TETRA, DMR, and cdma2000 are mentioned. The aim of the paper is to present innovative trunking solutions based on the LTE system working both in FDD and TDD mode. The architecture of LTE trunked radio is shown as well as new services possible to implementation are described. The way of TETRA and...

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  • Aspects of multistation quantum information broadcasting

    We study quantum information transmission over multiparty quantum channel. In particular, we show an equivalence of different capacity notions and provide a multiletter characterization of a capacity region for a general quantum channel with k senders and m receivers. We point out natural generalizations to the case of two-way classical communication capacity. (C) 2010 Elsevier B.V. All rights reserved.

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  • Analiza bezpieczeństwa funkcjonalnego i ochrony informacji w rozproszonych systemach komputerowych pełniących funkcje sterowania i zabezpieczeń

    W niniejszym artykule przedstawiona została problematyka związana z analizą bezpieczeństwa funkcjonalnego rozproszonych systemów sterowania i automatyki zabezpieczeniowej z uwzględnieniem zagadnień ochrony informacji. Powinny być one rozpatrywane w sposób zintegrowany w zależności od rodzaju komunikacji stosowanej do transmisji danych. W tym celu zaproponowano podział analizowanych systemów na trzy kategorie. Zaproponowane podejście...

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  • Analiza bezpieczeństwa funkcjonalnego i ochrony informacji w rozproszonych systemach komputerowych pełniących funkcje sterowania i zabezpieczeń

    W niniejszym artykule przedstawiona została problematyka związana z analizą bezpieczeństwa funkcjonalnego rozproszonych systemów sterowania i automatyki zabezpieczeniowej z uwzględnieniem zagadnień ochrony informacji. Powinny być one rozpatrywane w sposób zintegrowany w zależności od rodzaju komunikacji stosowanej do transmisji danych. W tym celu zaproponowano podział analizowanych systemów na trzy kategorie. Zaproponowane podejście...

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  • Substrate Integrated Waveguide-Based Frequency-Tunable Self-Octaplexing Antenna

    Publikacja

    This communication presents the first-ever substrate integrated waveguide (SIW)-based frequency-tunable self-octaplexing antenna (SOA) for wireless communication. The structure is arranged by implementing eight distinct patches with planar 50-ohm feedlines at the top of the SIW cavity, which realize eight distinct resonant frequencies. Independent tuning of each resonant frequency is achieved by incorporating appropriately allocated...

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  • Hybrid Approach to Networked Control System

    Publikacja

    - Rok 2013

    Effcient control of Networked Control System (NCS) is a challenge, as the control methods need to deal with non-deterministic variable delays and data loss. This paper presents a novel hybrid approach to NCS where Model Predictive Control (MPC) is applied as a main controller and implicit switching MPC is used for data transmission control in event-driven shared communication medium, leading to complex control system with active...

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  • Module of priorities for public transport vehicles in the TRISTAR system

    Publikacja

    One of the most important elements of the intelligent traffic control systems is the ability to control movement in such a way as to privilege the selected users movement, in particular public transport vehicles. Implemented at the Tri-City the TRISTAR system will also have a module for prioritizing public transport vehicles. The article presents a characteristics of the priority action system: the way of communication with the...

  • Taxonomy of Schemes for Resilient Routing

    Publikacja

    - Rok 2020

    This chapter provides a taxonomy of schemes for resilient routing followed by a discussion of their application to contemporary architectures of communication networks. In particular, a general classification of schemes for resilient routing is first presented followed by a description of the reference schemes for IP networks. The chapter in its later part focuses on the representative techniques of resilient routing for a multi-domain...

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  • ECHOES REDUCTION DURING DIGITAL DATA TRANSMISSION IN HYDROACOUSTIC CHANNEL – LABORATORY EXPERIMENT

    Publikacja

    - Rok 2019

    The 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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  • Text Mining Algorithms for Extracting Brand Knowledge; The fashion Industry Case

    Publikacja

    - Rok 2018

    Brand knowledge is determined by customer knowledge. The opportunity to develop brands based on customer knowledge management has never been greater. Social media as a set of leading communication platforms enable peer to peer interplays between customers and brands. A large stream of such interactions is a great source of information which, when thoroughly analyzed, can become a source of innovation and lead to competitive advantage....

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  • Analyzing and Visualizing Government-Citizen Interactions on Twitter to Support Public Policy-making

    Publikacja

    - Digital Government: Research and Practice - Rok 2020

    Twitter is widely adopted by governments to communicate with citizens. It has become a major source of data for analyzing how governments communicate with citizens and how citizens respond to such communication, uncovering important insights about government-citizen interactions that could be used to support public policy-making. This article presents research that aims at developing a software tool called Twitter Analytics for...

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  • Quality Expectations of Mobile Subscribers

    Mobile systems, by nature, have finite resources. Radio spectrum is limited, expensive and shared between many users and services. Mobile broadband networks must support multiple applications of voice, video and data on a single IP-based infrastructure. These converged services each have unique traffic holding and quality requirements. A positive user experience must be obtained through efficient partitioning of the available wireless...

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  • Overcoming Challenges of Virtual Scrum Teams: Lessons Learned Through an Action Research Study

    Publikacja

    - Rok 2023

    After the COVID-19 breakout, agile teams found themselves in situations that “pure agilists” and textbooks on agile methods had preferred to ignore. Whereas agile mindsets helped them to quickly shift to remote work, mere virtualization of agile practices often proved insufficient, and several challenges emerged. This paper reports on an Action Research project carried out in Lufthansa Systems Poland with the aim of (1) revisiting...

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  • A diplexer design method using an augmented channel filter approach

    Publikacja

    Continuous development in RFID andmicrocontrollers technologies gives new possibilities to createsystems that are able to integrate a lot of sensors based ondifferent technologies. This integration brings us closer to realizethe Ubiquitous Network Society vision. However, many problemsmust be addressed before we will benefit from such systems. Inthis paper we describe concept of integrating RFID technologywith other sensors technologies...

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  • Are quantum correlations symmetric?

    Publikacja

    - QUANTUM INFORMATION & COMPUTATION - Rok 2010

    We provide operational definition of symmetry of entanglement: An entangled state contains symmetric entanglement if its subsystems can be exchanged (swapped) by means of local operations and classical communication. We show that in general states have asymmetric entanglement. This allows to construct nonsymmetric measure of entanglement, and a parameter that reports asymmetry of entanglement contents of quantum state. We propose...

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  • Introduction to the ONDM 2022 special issue

    Publikacja
    • J. Turkiewicz
    • T. Gomes
    • M. Klinkowski
    • J. Rak
    • M. Tornatore

    - Journal of Optical Communications and Networking - Rok 2023

    This JOCN special issue contains extended versions of selected papers presented at the 26th International Conference on Optical Network Design and Modeling (ONDM 2022), which took place 16–19 May 2022 at Warsaw University of Technology, Warsaw, Poland. The topics covered by the papers represent trends in optical networking research: application of machine learning to network management, cross-layer network performance optimization,...

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  • Integrated Control in High-Speed Networks Using Constrained Model Predictive Control

    Publikacja

    - Rok 2013

    This paper studies congestion control in high-speed communication networks using Model Predictive Control (MPC). Network traffic is assumed to consist of best-effort and priority traffic sources. An integrated controller consisting of two control parts is designed. The controller calculates the capacity for priority sources and the input rate of best-effort sources. MPC is desirable as it can take into account the constraints on...

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  • Remote Monitoring System for Impedance Spectroscopy using Wireless Sensor Network

    Publikacja

    The architecture of a miniaturized impedanceanalyser with wireless communication module for remoteImpedance Spectroscopy (IS) of anticorrosion coatings ondifficult-to-reach objects (e.g. on the steel construction ofthe bridge) is described in this paper. Some practical aspectsof implementation of a Wireless Sensor Network (WSN) arealso discussed. A low scale, middle range, WSN networkcomposed of a Base Station (BS) with a Personal...

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  • Security Evaluation of IT Systems Underlying Critical Networked Infrastructures

    Publikacja

    - Rok 2008

    Critical infrastructures have become highly dependent on information and communication technology (ICT). The drawback of this situation is that the consequences of disturbances of the underlying ICT networks may be serious as cascading effects can occur. This raises a high demand for security assurance, with a high importance assigned to security evaluations. In this paper we present an experiment-centric approach for the characterisation...

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  • The role of the human factor in the companies' innovativeness

    Publikacja

    - Rok 2015

    Innovation is one of the factors enabling the development of both individual companies and entire economies. While previously the possibilities offered by technology were focused on, including information and communication technology (ICT), recently the potential of human resources has been gaining more and more attention. This capital — often underestimated — can in the right conditions and with a conducive organizational culture...

  • On possible applications of media described by fractional-order models in electromagnetic cloaking

    The purpose of this paper is to open a scientific discussion on possible applications of media described by fractional-order (FO) models (FOMs) in electromagnetic cloaking. A 2-D cloak based on active sources and the surface equivalence theorem is simulated. It employs a medium described by FOM in communication with sources cancelling the scattered field. A perfect electromagnetic active cloak is thereby demonstrated with the use...

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  • Optimization of Data Assignment for Parallel Processing in a Hybrid Heterogeneous Environment Using Integer Linear Programming

    Publikacja

    In the paper we investigate a practical approach to application of integer linear programming for optimization of data assignment to compute units in a multi-level heterogeneous environment with various compute devices, including CPUs, GPUs and Intel Xeon Phis. The model considers an application that processes a large number of data chunks in parallel on various compute units and takes into account computations, communication including...

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  • Overview of Metamaterials-Integrated Antennas for Beam Manipulation Applications: The Two Decades of Progress

    Publikacja

    - IEEE Access - Rok 2022

    Metamaterials (MMs) are synthetic composite structures with superior properties not found in naturally occurring materials. MMs have gained massive attention over the last two decades because of their extraordinary properties, such as negative permittivity and permeability. These materials enable many applications in communication subsystems, especially in the field of antenna design, to enhance gain, bandwidth, and efficiency,...

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  • IoT protocols, architectures, and applications

    Publikacja
    • C. Buratti
    • E. G. Ström
    • L. Feltrin
    • L. Clavier
    • G. Gardašević
    • T. Blazek
    • L. Berbakov
    • T. C. Balan
    • L. Orozco-Barbosa
    • C. Anton-Haro... i 2 innych

    - Rok 2021

    The proliferation of embedded systems, wireless technologies, and Internet protocols have enabled the IoT to bridge the gap between the virtual and physical world enabling the monitoring and control of the environment by data processing systems. IoT refers to the inter-networking of everyday objects that are equipped with sensing, computation, and communication capabilities. These networks can collaboratively interact and perform...

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  • Wireless intelligent audio-video surveillance prototyping system

    Publikacja

    The presented system is based on the Virtex6 FPGA and several supporting devices like a fast DDR3 memory, small HD camera, microphone with A/D converter, WiFi radio communication module, etc. The system is controlled by the Linux operating system. The Linux drivers for devices implemented in the system have been prepared. The system has been successfully verified in a H.264 compression accelerator prototype in which the most demanding...

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  • Blended Learning Model for Computer Techniques for Students of Architecture

    Abstract: The article summarizes two-year experience of implementing hybrid formula for teaching Computer Techniques at the Faculty of Architecture at the Gdansk University of Technology. Original educational e-materials, consisting of video clips, text and graphics instructions, as well as links to online resources are embedded in the university e-learning educational platform. The author discusses technical constraints associated...

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  • Laboratory Stand for Wideband Analysis Radiocommunication Signals

    Publikacja

    - Rok 2012

    A laboratory stand for wideband analysis radiocommunication signals is presented in the paper. The stand is designed for signals acquisition in wide spectrum and research a field of digital signal processing. Procedures used for simultaneous acquiring many frequency channels in selected wide band are described. The method of detection of direct sequence spread spectrum signals (DS SS) which power spectral density is lower than...

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  • Laboratory stand for wideband analysis radiocommunication signals

    Publikacja

    - Rok 2011

    A laboratory stand for wideband analysis radiocommunication signals is presented in the paper. The stand is designed for signals acquisition in wide spectrum and research a field of digital signal processing. Procedures used for simultaneous acquiring many frequency channels in selected wide band are described. The method of detection of direct sequence spread spectrum signals (DS SS) which power spectral density is lower than...

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  • Supporting Assurance by Evidence-based Argument Services

    Structured arguments based on evidence are used in many domains, including systems engineering, quality assurance and standards conformance. Development, maintenance and assessment of such arguments is addressed by TRUST-IT methodology outlined in this paper. The effective usage of TRUST-IT requires an adequate tool support. We present a platform of software services, called NOR-STA, available in the Internet, supporting key activities...

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  • Experimental test of nonclassicality with arbitrarily low detection efficiency

    Publikacja

    - PHYSICAL REVIEW A - Rok 2020

    We theoretically introduce and experimentally demonstrate the realization of a nonclassicality test that allows for arbitrarily low detection efficiency without invoking an extra assumption of independence of the devices. Our test and its implementation is set in a prepare-and-measure scenario with an upper limit on the classical communication capacity of the channel through which the systems are communicated. The essence for our...

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  • Multi-objective Tabu-based Differential Evolution for Teleportation of Smart Virtual Machines in Private Computing Clouds

    Publikacja

    - Rok 2021

    We propose a multi-objective approach for using differential evolution algorithm with tabu search algorithm as an additional mutation for live migration (teleportation) of virtual machines. This issue is crucial in private computing clouds. Teleportation of virtual machines is supposed to be planned to determine Pareto-optimal solutions for several criteria such as workload of the bottleneck host, communication capacity of the...

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  • High Isolation Metamaterial-based Dual-band MIMO Antenna for 5G Millimeter-wave Applications

    This article presents a high-isolation metamaterial-based dual-band multiple-input multiple-output (MIMO) antenna for 5G millimeter-wave communication networks. The proposed antenna is a pentagon-shaped monopole that provides a dual-band response with a wide operating bandwidth at 5G 28/28 bands. The antenna is printed on 0.508-mm-thick Rogers RT5880 substrate of relative permittivity ɛr =2.2. It exhibits a small physical size...

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  • Parallelization of large vector similarity computations in a hybrid CPU+GPU environment

    Publikacja

    The paper presents design, implementation and tuning of a hybrid parallel OpenMP+CUDA code for computation of similarity between pairs of a large number of multidimensional vectors. The problem has a wide range of applications, and consequently its optimization is of high importance, especially on currently widespread hybrid CPU+GPU systems targeted in the paper. The following are presented and tested for computation of all vector...

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  • Application of unmanned USV surface and AUV underwater maritime platforms for the monitoring of offshore structures at sea

    The operation of offshore structures at sea requires the implementation of advanced systems for their permanent monitoring. There is a set of novel technologies that could be implemented to deliver a higher level of effective and safe operation of these systems. A possible novel solution may be the application of a new maritime unmanned (USV) surface and underwater vehicles/platforms (AUV). Application of such vehicles/platforms...

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  • Stationary underwater channel experiment: Acoustic measurements and characteristics in the Bornholm area for model validations

    Publikacja

    - HYDROACOUSTICS - Rok 2016

    The underwater acoustical channel is time-variant, and even on small time scales there is often existing no ‘acoustical frozen ocean’. Popular is the use of WSSUS-channel transmission modeling (Wide-Sense Stationary Uncorrelated Scattering) for the stochastic description of bandpass signals in GSM mobile phones with moving participants; since this results in a halved number of model parameters. For underwater sound applications...

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  • How much is Impact Factor worth?

    Publikacja

    - Rok 2019

    The  purpose  of  this   work  is  to  present  an aspect  of  counting citations,  which is  correlated  to  the Impact  Factor,  very  important  for journals  in  scientific communication,   and   provides   information   about   the position of a scientific journal in a particular research area. Sometimes citations don’t count in a research output, e.g. if an article is  published  in a predatory  journal.  Those journals ...

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  • A method for testing the wide-sense stationary uncorrelated scattering assumption fulfillment for an underwater acoustic channel

    Wide-sense stationary and uncorrelated scattering (WSSUS) assumptions are often applied for the statistical description of wireless communication channels. However, in the case of underwater acoustic channels the WSSUS model is of limited value. The degree of similarity of in-phase and quadrature components of the channel impulse response, measured with the use of bandpass modulated signals, can be used as an indicator of WSSUS...

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  • Selected properties and parameters of radio channel impulse response estimation in ISM 2.4 GHz band

    Publikacja

    - Proceedings of SPIE - Rok 2019

    The article presents experimental research indicating that the impulse response of the communication channel, determined in practice, are not of an universal character, but only represent its approximate value for the frequency on which this measurement was made. Phases for each of the replicas of the measurement signal were determined during the analysis of the received signals in the baseband. Phase changes of individual replicas...

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  • Exploring ontological approach for user requirements elicitation in design of online virtual agents

    Effective user requirements elicitation is a key factor for the success of software development projects. There are many qualitative and quantitative research studies that promulgate particular methods and show the application of user requirements elicitation in particular domains. However, few try to eliminate the burden of ambiguity in gathered data, naturally occurring in different groups of stakeholders. This paper deals with...

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  • Standards on Cyber Security Assessment of Smart Grid

    Security evaluation of communication systems in smart grid poses a great challenge to the developers and operators. In recent years many new smart grid standards were proposed, which paradoxically results in the difficulty in finding a relevant publication in this plethora of literature. This paper presents the results of a systematic analysis which aimed at addressing this issue by identifying standards that present sound security...

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  • Quantum superadditivity in linear optics networks: Sending bits via multiple-access Gaussian channels

    Publikacja

    Superadditivity effects of communication capacities are known in the case of discrete variable quantum channels. We describe the continuous variable analog of one of these effects in the framework of Gaussian multiple access channels (MACs). Classically, superadditivity-type effects are strongly restricted: For example, adding resources to one sender is never advantageous to other senders in sending their respective information...

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  • A Point Set Connection Problem for Autonomous Mobile Robots in a Grid

    Publikacja

    - COMPUTING AND INFORMATICS - Rok 2012

    Consider an orthogonal grid of streets and avenues in a Manhattan-like city populated by stationary sensor modules at some intersections and mobile robots that can serve as relays of information that the modules exchange, where both module-module and module-robot communication is limited to a straight line of sight within the grid. The robots are oblivious and move asynchronously. We present a distributed algorithm that, given...

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  • Fast Fading Influence on the Deep Learning-Based LOS and NLOS Identificationin Wireless Body Area Networks

    In the article, the fast fading influence on the proposed DL (Deep Learning) approach for LOS (Line-of-Sight) and NLOS (Non-Line-of-Sight) conditions identification in Wireless Body Area Networks is investigated. The research was conducted on the basis of the off-body communication measurements using the developed mobile measurement stand, in an indoor environment for both static and dynamic scenarios. The measurements involved...

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  • The project IDENT: Multimodal biometric system for bank client identity verification

    Biometric identity verification methods are implemented inside a real banking environment comprising: dynamic handwritten signature verification, face recognition, bank cli-ent voice recognition and hand vein distribution verification. A secure communication system based on an intra-bank client-server architecture was designed for this purpose. Hitherto achieved progress within the project is reported in this paper with a focus...

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  • Realizacja mobilnego urządzenia do wytwarzania kurtyny elektromagnetycznej do zastosowań specjalnych

    In the article the assumptions, design and realisation of the technological demonstrator of a mobile device for generating an electromagnetic curtain (AEGIS) were presented, both in the area of hardware and software. The device is designed to block radio communication by which it is possible to detonate the Radio Controlled Improvised Explosive Devices (RCIEDs). The preliminary laboratory tests of the demonstrator for generating...

  • Application of multi-criteria method to assess the usefulness of a hydrotechnical object for floating housing

    This publication presents the analysis of three hydrotechnical objects located in the Municipality of Gdańsk with a view of mooring Floating Houses. The assessment of the adaptation of a hydrotechnical object has been carried out by a multi- criteria method AHP and using the main criteria such as: mooring system, communication with the mainland, availability of the utility networks, waste disposal and location of the parking spaces....

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  • Sonar Pulse Detection Using Chirp Rate Estimation and CFAR Algorithms

    Publikacja

    This paper presents a new approach to sonar pulse detection. The method uses chirp rate estimators and algorithms for the adaptive threshold, commonly used in radiolocation. The proposed approach allows detection of pulses of unknown parameters, which may be used in passive hydrolocation or jamming detection in underwater communication. Such an analysis is possible thanks to a new kind of imaging, which presents signal energy in...

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  • Characterizing the Performance of <span class="sc">xor</span> Games and the Shannon Capacity of Graphs

    Publikacja

    - PHYSICAL REVIEW LETTERS - Rok 2014

    In this Letter we give a set of necessary and sufficient conditions such that quantum players of a two-party xor game cannot perform any better than classical players. With any such game, we associate a graph and examine its zero-error communication capacity. This allows us to specify a broad new class of graphs for which the Shannon capacity can be calculated. The conditions also enable the parametrization of new families of games...

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  • Deep Learning-Based LOS and NLOS Identification in Wireless Body Area Networks

    In this article, the usage of deep learning (DL) in ultra-wideband (UWB) Wireless Body Area Networks (WBANs) is presented. The developed approach, using channel impulse response, allows higher efficiency in identifying the direct visibility conditions between nodes in off-body communication with comparison to the methods described in the literature. The effectiveness of the proposed deep feedforward neural network was checked on...

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  • Decentralized control of a different rated parallel UPS systems

    Publikacja

    The paper presents the single phase uninterruptible power supply (UPS) system with galvanic separated DC-AC-DC-AC converters operating in parallel. The CAN physical layer based system of communication between converters has been developed and applied, which allow to utilize a decentralized master-slave control providing high availability factor of the whole UPS system. The control system of particular converters has been developed...

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