Institute of Electron Technology
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2189 research outputs found
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SHaPe: A Honeypot for Electric Power Substation, Journal of Telecommunications and Information Technology, 2015, nr 4
Get PDFSupervisory Control and Data Acquisition (SCADA) systems play a crucial role in national critical infrastructures, and any failure may result in severe damages. Initially SCADA networks were separated from other networks and used proprietary communications protocols that were well known only to the device manufacturers. At that time such isolation and obscurity ensured an acceptable security level. Nowadays, modern SCADA systems usually have direct or indirect Internet connection, use open protocols and commercial-o-the-shelf hardware and software. This trend is also noticeable in the power industry. Present substation automation systems (SASs) go beyond traditional SCADA and employ many solutions derived from Information and Communications Technology (ICT). As a result electric power substations have become more vulnerable for cybersecurity attacks and they need ICT security mechanisms adaptation. This paper shows the SCADA honeypot that allows detecting unauthorized or illicit traffic in SAS which communication architecture is defined according to the IEC 61850 standard
Measuring Electromagnetic Emissions from Active Landslides, Journal of Telecommunications and Information Technology, 2015, nr 2
Get PDFThe paper describes the mechanism of electromagnetic emission generation in active landslides and measuring techniques. Special attention is given to electromagnetic emission fields. The author proposes an original system for measuring both continuous and pulsed magnetic emission of land-slides. For such measurements boreholes must be drilled in the landslide. It is essential that the tubing constituting theborehole’s lining be made of a material which does not attenuate magnetic fields. Besides its primary function, i.e. the registration of landslide magnetic field activity, the system can be used for the structural inhomogeneity of rock strata examination subjected to considerable stresses. The results of examinations of active and inactive landslide in Poland are presented. The post-extraction cave in the SMZ Jelsava Mine in Jelsava, Slovakia, is presented too
Performance Evaluation of Cognitive Radio Network Based on 2-D Markov Chain, Journal of Telecommunications and Information Technology, 2015, nr 3
Get PDFThe objective of cognitive radio network is to enhance the wireless network spectrum utilization. In such a network, two types of users are enlisted, namely primary user (PU) and secondary user (SU). The PU can access any channel in case of its availability, but SU users have lower priority and can access a channel only when it is unused by PUs. The performance of such a network solely depends on two traffic parameters: probability of false alarm and probability of misdetection. In this paper the performance of such a network is analyzed based on two dimensional Markov chain including those parameters. The main contribution of this paper is to evaluate blocking probability and PU and SU throughput using the state transition chain instead of existing statistical analysis
Silent Calls – Causes and Measurements, Journal of Telecommunications and Information Technology, 2015, nr 1
Get PDFThe quality of telephone services is very important from either operator or subscriber point of view. One of the negative phenomenon which affects quality of telephone services is lack of speech signal during a call. This situation occurs relatively frequently in mobile telephony, and is called silent call (SC). Lack of speech signal can occur only once or many times during the call, and degrade connection quality. In this paper, an analysis of this phenomenon is presented. The research base are the results of measurements mobile network one of operators in Trójmiasto a large urban area consisting of three cities: Gdańsk, Gdynia, and Sopot. To estimate impact of silent calls on speech quality, mean opinion score index was calculated using POLQA algorithm
Availability of WDM Multi Ring Networks, Journal of Telecommunications and Information Technology, 2015, nr 1
Get PDFThis paper presents a new approach to modeling the availability of the networks composed of multiple interconnected rings in two nodes. For availability modeling method algebraic formulation is used. Using this method, through the availability of multiple ring networks consisting of two and three-rings connected to two nodes, a general expression for the availability between two terminals of multiple ring networks is derived. To perform the expression some real assumptions were taken and the analytical calculation showed that the use of these expressions under these assumptions provides real values for availability between the two terminals of multiple ring networks. Information on the availability of links and nodes is taken from previously published works
Analysis of Polymorphic DNA Sequences in the Identi cation of Individuals and its Possible Use in Biometric Systems, Journal of Telecommunications and Information Technology, 2015, nr 2
Get PDFThe article presents the achievements in DNA forensic science practice, the latest developments as well as future trends. The article concerns also other than forensic DNA applications as well as expectations, concerns and obstacles. DNA identification technology unlike other biometric techniques requires the collection of biological material and the identification is not performed in real time. DNA utilized in most of forensic identification, is present almost in every living cell in the body. What is more, each cell of the same body has the same DNA molecule which means that it is possible to compare the DNA sampled from different sources, for example saliva with blood or semen from the same person. Rapid development and reliability of DNA technology contribute to the fact that the analysis of polymorphic DNA sequences constitutes a very important evidence used in the court. The unique properties of DNA and rapid development of DNA analytical devices allow to claim that DNA may assume a more important position amongst biometric data in the future
Historical Perspectives of Development of Antique Analog Telephone Systems, Journal of Telecommunications and Information Technology, 2015, nr 3
Get PDFLong distance voice communication has been always of great interest to human beings. His untiring efforts and intuition from many years together was responsible for making it to happen to a such advanced stage today. This paper describes the development time line of antique telephone systems, which starts from the year 1854 and begins with the very early effort of Antonio Meucci and Alexander Graham Bell and ends up to the telephone systems just before digitization of entire telecommunication systems. The progress of development of entire antique telephone systems is highlighted in this paper. The coverage is limited to only analog voice communication in a narrow band related to human voice
The Use of Genetic Algorithms for Searching Parameter Space in Gaussian Process Modeling, Journal of Telecommunications and Information Technology, 2001, nr 3
Get PDFThe aim of the paper is to present the possibilities of modeling the experimental data by Gaussian processes. Genetic algorithms are used for finding the Gaussian process parameters. Comparison of data modeling accuracy is made according to neural networks learned by Kalman filtering. Concrete hysteresis loops obtained by the experiment of cyclic loading are considered as the real data time series
FIM-SIM: Fault Injection Module for CloudSim Based on Statistical Distributions, Journal of Telecommunications and Information Technology, 2014, nr 4
Get PDFThe evolution of ICT systems in the way data is accessed and used is very fast nowadays. Cloud computing is an innovative way of using and providing computing resources to businesses and individuals and it has gained a faster popularity in the last years. In this context, the user’s expectations are increasing and cloud providers are facing huge challenges. One of these challenges is fault tolerance and both researchers and companies have focused on finding and developing strong fault tolerance models. To validate these models, cloud simulation tools are used as an easy, flexible and fast solution. This paper proposes a Fault Injector Module for CloudSim tool (FIM-SIM) for helping the cloud developers to test and validate their infrastructure. FIM-SIM follows the event- driven model and inserts faults in CloudSim based on statistical distributions. The authors have tested and validated it by conducting several experiments designed to highlight the statistical distribution influence on the failures generated and to observe the CloudSim behavior in its current state and implementation
Szybka analiza zaburzeń krótkotrwałych. Opracowany w Instytucie Łączności Analizator ACA-4c. Telekomunikacja i Techniki Informacyjne, 2014, nr 3-4
Get PDFW artykule opisano opracowany i wdrożony do produkcji w Instytucie Łączności analizator zakłóceń krótkotrwałych ACA-4c, pozwalający na skrócenie czasu badań wyrobów w zakresie emisji trzasków. Urządzenie to umożliwia automatyczne wykonywanie kompleksowej analizy trzasków, równocześnie dla czterech znormalizowanych częstotliwości i na obu poziomach analizy. Zbudowane zostało w oparciu o bogate doświadczenie Instytutu i spełnia wszystkie wytyczne zawarte w normach