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A survey of neural networks usage for intrusion detection systems
PublikacjaIn recent years, advancements in the field of the artificial intelligence (AI) gained a huge momentum due to the worldwide appliance of this technology by the industry. One of the crucial areas of AI are neural networks (NN), which enable commer‐ cial utilization of functionalities previously not accessible by usage of computers. Intrusion detection system (IDS) presents one of the domains in which neural networks are widely tested...
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A new quaternion-based encryption method for DICOM images
PublikacjaIn this paper, a new quaternion-based lossless encryption technique for digital image and communication on medicine (DICOM) images is proposed. We have scrutinized and slightly modified the concept of the DICOM network to point out the best location for the proposed encryption scheme, which significantly improves speed of DICOM images encryption in comparison with those originally embedded into DICOM advanced encryption standard...
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Subarachnoid Space: New Tricks by an Old Dog
PublikacjaPurpose: The purpose of the study was to: (1) evaluate the subarachnoid space (SAS) width and pial artery pulsation in both hemispheres, and (2) directly compare magnetic resonance imaging (MRI) to near-infrared transillumination/backscattering sounding (NIR-T/BSS) measurements of SAS width changes in healthy volunteers.Methods: The study was performed on three separate groups of volunteers, consisting in total of 62 subjects (33...
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Secure Quaternion Feistel Cipher for DICOM Images
PublikacjaAn improved and extended version of a quaternion-based lossless encryption technique for digital image and communication on medicine (DICOM) images is proposed. We highlight and address several security flaws present in the previous version of the algorithm originally proposed by Dzwonkowski et al. (2015). The newly proposed secure quater- nion Feistel cipher (S-QFC) algorithm...
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Fluctuation-enhanced scent sensing using a single gas sensor
PublikacjaWykrywanie zapachów podczas aromaterapii może być przeprowadzone za pomocą pojedynczego sensora gazów. W pracy rozważono efektywność detekcji zapachów olejków eterycznych za pomocą rezystancji DC oraz zjawisk fluktuacyjnych w tych sensorach, typu TGS2600,TGS2602,TGS823. Badania koncentrowały się na praktycznym zastosowaniu w aromaterapii do określania intensywności emitowanego zapachu. Opisano szczegółowo system do emisji zapachów.
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A novel approach exploiting properties of convolutional neural networks for vessel movement anomaly detection and classification
PublikacjaThe article concerns the automation of vessel movement anomaly detection for maritime and coastal traffic safety services. Deep Learning techniques, specifically Convolutional Neural Networks (CNNs), were used to solve this problem. Three variants of the datasets, containing samples of vessel traffic routes in relation to the prohibited area in the form of a grayscale image, were generated. 1458 convolutional neural networks with...
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Matrix-based robust joint fingerprinting and decryption method for multicast distribution of multimedia
PublikacjaThis paper addresses the problem of unauthorized redistribution of multimedia content by malicious users (pirates). The solution proposed here is a new joint fingerprinting and decryption method which meets the requirements for both imperceptibility and robustness of fingerprints and scalability in terms of design and distribution of fingerprinted multimedia content. The proposed method uses a simple block cipher based on matrix...
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Variable Fractional Delay Filter Design Using a Symmetric Window
PublikacjaIn this paper a numerically efficient method for designing a nearly optimal variable fractional delay (VFD) filter based on a simple and well-known window method is presented. In the proposed method a single window extracted from the optimal filter with fixed fractional delay (FD) is divided into even and odd part. Subsequently, the odd part is discarded and symmetric even part of the extracted window is used to design a family...
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Joint fingerprinting and decryption method for color images based on quaternion rotation with cipher quaternion chaining
PublikacjaThis paper addresses the problem of unauthorized redistribution of multimedia content by malicious users (pirates). In this method three color channels of the image are considered a 3D space and each component of the image is represented as a point in this 3D space. The distribution side uses a symmetric cipher to encrypt perceptually essential components of the image with the encryption key and then sends the encrypted data via...
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Application of Least Squares with Conditional Equations Method for Railway Track Inventory Using GNSS Observations
PublikacjaSatellite geodetic networks are commonly used in surveying tasks, but they can also be used in mobile surveys. Mobile satellite surveys can be used for trackage inventory, diagnostics and design. The combination of modern technological solutions with the adaptation of research methods known in other fields of science offers an opportunity to acquire highly accurate solutions for railway track inventory. This article presents the...
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Farrow structure implementation of fractional delay filter optimal in Chebyshev sense
PublikacjaW pracy omówiono problematykę implementacji filtrów ułamkowych opóźniających o zmiennym opóźnieniu w oparciu o strukturę Farrowa. Podejście to polega na obliczeniu próbek nowej odpowiedzi impulsowej filtru dla każdego wymaganego opóźnienia w opraciu o wielomiany o współczynnikach niezależnych od opóźnienia. Prowadzi to do znacznego zmniejszenia kosztów numerycznych implementacji w zastosowaniach wymagających częstej zmiany opóźnienia...
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MAPSERVER – INFORMATION FLOW MANAGEMENT SOFTWARE FOR THE BORDER GUARD DISTRIBUTED DATA EXCHANGE SYSTEM
PublikacjaIn this paper the architecture of the software designed for management of position and identification data of floating and flying objects in Maritime areas controlled by Polish Border Guard is presented. The software was designed for managing information stored in a distributed system with two variants of the software, one for a mobile device installed on a vessel, an airplane or a car and second for a central server. The details...
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Reversible Data Hiding in Encrypted DICOM Images Using Cyclic Binary Golay (23, 12) Code
PublikacjaIn this paper, a novel reversible data hiding method for encrypted images (RDHEI) is proposed. An efficient coding scheme based on cyclic binary Golay (23, 12) code is designed to embed additional data into the least significant bits (LSBs) of the encrypted image. The most significant bits (MSBs) are used to ensure the reversibility of the embedding process. The proposed scheme is lossless, and based on the receiver’s privileges,...
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Verification of the Analytical Traffic Model of a Multidomain IMS/NGN Using the Simulation Model
PublikacjaIn this paper we verify the previously proposed analytical traffic model of a multidomain Next Generation Network (NGN), which is standardized for delivering multimedia services based on the IP Multimedia Subsystem (IMS). For this reason a proper simulation model used, in which not theoretical queuing system models but the operation of real network elements and standardized call scenarios are accurately implemented. Consequently,...
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Gain deficit effect in the fractional delay filter design by the window method
PublikacjaMetoda okien jest sposobem szybkiego i skutecznego projektowania filtrów ułamkowoopóźniających. Jednakże wzmocnienie tak zaprojektowanego filtru różni się od zakładanej wartości idealnej. To zjawisko, nazywane deficytem wzmocnienia, negatywnie wpływa na jakoś projektowanego filtru. Artykuł poświęcono wynikom badań oraz metodom korekcji tego problemu. Omówiono wpływ współczynnika korekcji deficytu wzmocnienia na charakterystykę...
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Reversible data hiding in encrypted DICOM images using sorted binary sequences of pixels
PublikacjaIn this paper, a novel reversible data hiding method for encrypted DICOM images is proposed. The method utilizes binary decomposition of the input data paired with a sorting process of the obtained binary sequences to ensure efficient data embedding in each predefined data block for specific most significant bit (MSB) planes while exploiting the properties of run-length encoding. The proposed scheme is lossless, and based on the...
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Analysis of IMS/NGN Call Processing Performance Using Phase-Type Distributions Based on Experimental Histograms
PublikacjaThe paper describes our further research done with the proposed analytical and simulation traffic models of the Next Generation Network (NGN), which is standardized for delivering multimedia services with strict quality and includes elements of the IP Multimedia Subsystem (IMS). The aim of our models of a single IMS/NGN domain is to evaluate two standardized call processing performance parameters, which appropriate values are very...
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Influence of Self-Similar Traffic Type on Performance of QoS Routing Algorithms
PublikacjaProviding a Quality of Services (QoS) into current telecommunication networks based on packet technology is a big challenge nowadays. Network operators have to support a number of new services like voice or video which generate new type of traffic. This traffic serviced with QoS in consequence requires access to appropriate network resources. Additionally, new traffic type is mixed with older one, like best-effort. Analysis of...
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Sample Rate Conversion Based on Frequency Response Masking Filter
PublikacjaThe sample rate conversion with high resampling ratios requires low-pass digital filters with very narrow transition band which results in high computational complexity and makes filter design problematic. Therefore in this work we propose to use the FRM method, which breaks the filter with a narrow transition band into a group of filters with reduced design requirements. These decreases the number of non-zero coefficients and...
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A New Heuristic Algorithm for Effective Preemption in MPLS Networks
PublikacjaW artykule opisano nowy algorytm wywłaszczania przeznaczony dla sieci MPLS. Umożliwia on alokację zasobów sieci dla nowej ścieżki uwzględniając koszt usuniętych jednej lub wielu istniejących już ścieżek. Proponowany heurystyczny algorytm wybiera ścieżki do wywłaszczenia wykorzystując informację o topologii sieci. Używa funkcji optymalizacji minimalizującej stratę pasma na poziomie sieci. Przedstawiono i omówiono wyniki badań symulacyjnych...
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Neural network training with limited precision and asymmetric exponent
PublikacjaAlong with an extremely increasing number of mobile devices, sensors and other smart utilities, an unprecedented growth of data can be observed in today’s world. In order to address multiple challenges facing the big data domain, machine learning techniques are often leveraged for data analysis, filtering and classification. Wide usage of artificial intelligence with large amounts of data creates growing demand not only for storage...
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Simulator for Performance Evaluation of ASON/GMPLS Network
PublikacjaThe hierarchical control plane network architecture of Automatically Switched Optical Network with utilization of Generalized Multi-Protocol Label Switching protocols is compliant to next generation networks requirements and can supply connections with required quality of service, even with incomplete domain information. Considering connection control, connection management and network management, the controllers of this architecture...
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The model of end-to-end call setup time calculation for Session Initiation Protocol
PublikacjaEnd-to-end call setup delay is one of the most important grade of service (GoS) parameters for VoIP networks with Session Initiation Protocol (SIP). A typical subscriber wants to have a connection established as soon as possible. From the operator's perspective call setup time is also crucial because he needs to know how probability of successful packet transmission on SIP links is related to a call setup delay. Then he can make...
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Variable Ratio Sample Rate Conversion Based on Fractional Delay Filter
PublikacjaIn this paper a sample rate conversion algorithm which allows for continuously changing resampling ratio has been presented. The proposed implementation is based on a variable fractional delay filter which is implemented by means of a Farrow structure. Coefficients of this structure are computed on the basis of fractional delay filters which are designed using the offset window method. The proposed approach allows us to freely...
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Comments on “Closed Form Variable Fractional Time Delay Using FFT”
PublikacjaIn this letter drawbacks of the aforementioned paper are pointed out. The proposed approach is improved with minor modifications of the discrete frequency response. This allows for design of fractional delay filters which are close to optimal and can be efficiently implemented in the frequency domain using the sliding DFT based structure. Alternatively, the derived equivalent closed form formulae for offset windows can be used...
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Streaming Real-time Data in Distributed Dispatcher and Teleinformation Systems for Visualization of Multimedia Data of the Border Guard
PublikacjaSurveillance of the sea borders is a very important task for the Border Guard. Monitoring of country maritime border is an important task of the Border Guard. This task can be facilitated with the use of the technology enabling gathering information from distributed sources and its supervision and visualization. This task can be accomplished using a technology that allows to collect information from distributed sensors of different...
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Analytical Traffic Model for a Multidomain IMS/NGN Network Including Service and Transport Stratum
PublikacjaThis paper addresses the problem of modelling call processing performance (CPP) in a multidomain Next Generation Network (NGN) architecture including the elements of the IP Multimedia Subsystem (IMS) in service stratum and based on the Multiprotocol Label Switching (MPLS) technology in transport stratum. An analytical traffic model for such an architecture is proposed by integrating the formerly implemented submodels of service...
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Performance Evaluation of a Multidomain IMS/NGN Network Including Service and Transport Stratum
PublikacjaThe Next Generation Network (NGN) architecture was proposed for delivering various multimedia services with guaranteed quality. For this reason, the elements of the IP Multimedia Subsystem (IMS) concept (an important part of 4G/5G/6G mobile networks) are used in its service stratum. This paper presents comprehensive research on how the parameters of an IMS/NGN network and traffic sources influence mean Call Set-up Delay (E(CSD))...
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Stradar - Multimedia Dispatcher and Teleinformation System for the Border Guard
PublikacjaSecurity of national borders requires utilization of multimedia surveillance systems automatically gathering, processing and sharing various data. The paper presents such a system developed for the Maritime Division of the Polish Border Guard within the STRADAR project. The system, apart from providing communication means, gathers data, such as map data from AIS, GPS and radar receivers, videos and photos from camera or audio from...
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Deduplication of Tracked Objects Position Data at Single Observation Point of a Vessel Monitoring System
PublikacjaVessel Monitoring System (VMS) play a major role in safety navigation. In most cases they are based on two data sources, namely Automatic Identification System (AIS) and Automatic Radar Plotting Aids (ARPA). Integration of data obtained from these sources is an important problem, which needs to be solved in order to ensure the correct performance of a given VMS. In this paper basic functions which should be implemented in a tracked...
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Square Root Raised Cosine Fractionally Delaying Nyquist Filter - Design and Performance Evaluation
PublikacjaIn this paper we propose a discrete-time FIR (Finite Impulse Response) filter which is applied as a square root Nyquist filter and fractional delay filter simultaneously. The filter enables to substitute for a cascade of square root Nyquist filter and fractional delay filter in one device/algorithm. The aim is to compensate for transmission delay in digital communication system. Performance of the filter as a matched filter is...
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Traffic Model of IMS/NGN Architecture with Transport Stratum Based on MPLS Technology
PublikacjaGrowing expectations for a fast access to information create strong demands for a universal telecommunication network architecture, which provides various services with strictly determined quality. Currently it is assumed that these requirements will be satisfied by Next Generation Network (NGN), which consists of two stratums and includes IP Multimedia Subsystem (IMS) elements. To guarantee Quality of Service (QoS) all NGN stratums...
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The System of the Supervision and the Visualization of Multimedia Data for BG
PublikacjaMonitoring of country maritime border is an important task of the Border Guard. This task can be facilitated with the use of the technology enabling gathering information from distributed sources and its supervision and visualization. The system presented in the paper is an extension and enhancement of the previously developed distributed system map data exchange system. The added functionalities allow supplementation of map data...
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The Concept of Using the Decision-Robustness Function in Integrated Navigation Systems
PublikacjaThe diversity and non-uniformity of the positioning systems available in maritime navigation systems often impede the watchkeeping officer in the selection of the appropriate positioning system, in particular, in restricted basins. Thus, it is necessary to introduce a mathematical apparatus to suggest, in an automated manner, which of the available systems should be used at the given moment of a sea trip. Proper selection of the...
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Performance of FAN conception of traffic control in IP QoS networks
PublikacjaIn this paper we present the architectural implementation of Flow Aware Networking (FAN), a new approach for realizing QoS guarantees in the Internet. We also propose FAN traffic control algorithm which performs traffic control on flow level. Using the proposed FAN node model, we conduct simulation research to prove if FAN can be a new approach for realizing QoS guarantees. The basis of this research is finding a way to guarantee...
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Deduplication of Position Data and Global Identification of Objects Tracked in Distributed Vessel Monitoring System
PublikacjaVessel monitoring systems (VMS) play a very important role in safety navigation. In most cases, their structure is distributed and they are based on two data sources, namely Automatic Identification System (AIS) and Automatic Radar Plotting Aids (ARPA). Such approach results in several objects identification and position data duplication problems, which need to be solved in order to ensure the correct performance of a given VMS....
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Data visualization of marine objects on digital maps
PublikacjaThe paper presents the implementation of two multithreaded applications for data visualization of marine objects written in C#, designed to run on operator consoles with 32-bit or 64-bit Windows 7 OS. The article describes the most important functionality and features of the developed C# .NET user controls for data visualization on digital maps and in the configurable tables.
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Dynamic unattended measurement based routing algorithm for diffServ architecture
PublikacjaDynamic routing is very important in terms of assuring QoS in today's packet networks especially for streaming and elastic services. Existing solutions dedicated to dynamic routing are often too complicated and seem to be not usable in real time traffic scenarios where transferred traffic may vary significantly. This was the main reason for research and new routing mechanism proposal which should apply to today's packet networks....
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Design of a Multidomain IMS/NGN Service Stratum
PublikacjaThe paper continues our research concerning the Next Generation Network (NGN), which is standardized for delivering multimedia services with strict quality and includes elements of the IP Multimedia Subsystem (IMS). A design algorithm for a multidomain IMS/NGN service stratum is proposed, which calculates the necessary CSCF servers CPU message processing times and link bandwidths with respect to the given maximum values of mean...
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Visualization of events using various kinds of synchronized data for the Border Guard
PublikacjaSTRADAR project is dedicated to streaming real-time data in a distributed dispatcher and teleinfor-mation system of the Border Guard. The Events Visualization Post is a software designed for simultaneous visualization of data of different types in BG headquarters. The software allows the operator to visualize files, images, SMS, SDS, video, audio, and current or archival data on naval situation on digital maps. All the visualized...
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Real-time generator of AIS/ARPA/GPS data
PublikacjaThe paper presents a real-time generator of AIS/ARPA/GPS position data in the standardized NMEA 0183 text format. Position data are produced by a set of various types of ships simulated on the Polish part of the Baltic Sea and are generated on defined IP/UDP addresses and RS-232 ports. In the simulation an extensive set of input parameters is taken into account including the number of particular types of ships, their dimensions,...
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Performance Evaluation of Preemption Algorithms in MPLS Networks
PublikacjaPreemption is a traffic engineering technique in Multiprotocol Switching Networks that enables creation of high priority paths when there is not enough free bandwidth left on the route. Challenging part of any preemption method is to select the best set of paths for removal. Several heuristic methods are available but no wider comparison had been published before. In this paper, we discuss the dilemmas in implementing preemption...
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An Improved Convolutional Neural Network for Steganalysis in the Scenario of Reuse of the Stego-Key
PublikacjaThe topic of this paper is the use of deep learning techniques, more specifically convolutional neural networks, for steganalysis of digital images. The steganalysis scenario of the repeated use of the stego-key is considered. Firstly, a study of the influence of the depth and width of the convolution layers on the effectiveness of classification was conducted. Next, a study on the influence of depth and width of fully connected...
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QoS Resource Reservation Mechanisms for Switched Optical Networks
PublikacjaThe paper regards the problem of resource reservation mechanisms for Quality of Service support in switched optical networks. The authors propose modifications and extensions for resources reservation strategy algorithms with resources pools, link capacity threshold and adaptive advance reservation approach. They examine proposed solutions in Automatically Switched Optical Network with Generalized Multi-Protocol Label Switching...
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Evolutionary Algorithms in MPLS network designing
PublikacjaMPLS technology become more and more popular especially in core networks giving great flexibility and compatibility with existing Internet protocols. There is a need to optimal design such networks and optimal bandwidth allocation. Linear Programming is not time efficient and does not solve nonlinear problems. Heuristic algorithms are believed to deal with these disadvantages and the most promising of them are Evolutionary Algorithms....
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The central server of the Border Guard's distributed multimedia system for monitoring and visualisation of ongoing and archival events
PublikacjaThe paper presents the architecture and functionalities of the central server (CENTER) of the distributed system for the Polish Border Guard (BG) for monitoring maritime areas. The overall system has been extended to incorporate, apart from map data, also different multimedia elements such as video from cameras or audio from telephone connections operated by BG units. This requires new system elements: Archive Servers for storing...
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Passive Variable Fractional Delay Filter Design using Distributed Maximal Flatness Method
PublikacjaW pracy przedstawiono nową metodę projektowania pasywnych filtrów ułakowoopóźniających opartą na metodzie rozproszonej maksymalnej płaskości. W zaproponowane podejście jest uogólnieniem najbardziej popularnej metody projektowania filtrów maksymalnie płaskich - metody projektowania filtrów maksymalnie płaskich. Filtr maksymalnie płaski cechuje bardzo dobra jakość jedynie w wąskim paśmie wokół częstotliwości zerowej, ale jego istotną...
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Radar data fusion in the STRADAR system
PublikacjaThe main task of the Polish Border Guard is protection of the country’s border which requires utilization of multimedia surveillance systems automatically gathering, processing and sharing various data. The paper presents such a system developed for the Maritime Division of the Polish Border Guard within the STRADAR project and the problem of fusion of radar data in this system. The system, apart from providing communication means,...
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Badanie i analiza właściwości szerokopasmowej sieci dostępowej C-MUX firmy Marconi Communications
PublikacjaPrzeanalizowano właściwości szerokopasmowej sieci dostępowej C-MUX firmy Marconi Communications i opracowano szczegółową metodologię badań. Przedstawiono i omówiono wyniki badań sieci C-MUX i opracowano wnioski szczegółowe.
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Badania i analiza właściwości szerokopasmowej sieci dostępowej SDA firmy DGT
PublikacjaPrzedstawiono przeprowadzone badania i analizę właściwości szerokopasmowej sieci dostępowej SDA - DGT. Zaprezentowano: architekturę systemu, możliwe topologie, oferowane usługi oraz system zarządzania DGT-SDA.Omówiono opracowaną metodologię badań i uzyskane wyniki. Przedstawiono opracowane wnioski szczegółowe i wnioski ogólne.