Institute of Electron Technology
Biblioteka Cyfrowa Instytutu Łączności / National Institute of Telecomunications: Digital LibraryNot a member yet
2189 research outputs found
Sort by
Zużycie energii przez urządzenia abonenta sieci szerokopasmowej i jego konsekwencje. Telekomunikacja i Techniki Informacyjne, 2012, nr 1-2
Get PDFArtykuł prezentuje analizę zużycia energii elektrycznej przez własne urządzenia abonenta przyłączane do szerokopasmowej sieci dostępowej nowej generacji oraz jego konsekwencje dla systemu energetycznego i środowiska naturalnego. Dostęp do usług oferowanych przez sieć szerokopasmową motywuje abonenta do wyposażenia gospodarstwa domowego w nowe urządzenia elektroniczne jak komputery i odbiorniki telewizyjne HD oraz bardziej intensywnej eksploatacji już posiadanych, prowadząc do wzrostu zużycia energii elektrycznej. Problem ten jest zwykle pomijany w literaturze, gdzie dominują analizy ograniczone do zużycia energii w samej sieci telekomunikacyjnej, tworzące złudny niestety obraz „zielonej” technologii. Przedstawiono też analizę ekonomiczną skutków pokrycia kraju siecią szerokopasmową
Optimal Pump Scheduling for Large Scale Water Transmission System by Linear Programming, Journal of Telecommunications and Information Technology, 2012, nr 3
Get PDFLarge scale potable water transmission system considered in this paper is the Toronto Water System, one of the largest potable water supply networks in North America. The main objective of the ongoing Transmission Operations Optimizer project consists in developing an advanced tool for providing such pumping schedules for 153 pumps, that all quantitative requirements with respect to the system operation are met, while the energy costs are minimized. We describe here a linear, so-called SimplifiedModel (SM), based on mass-balance equations, which is solved on week horizon and delivers boundary conditions for so-called Full Model (FM), which is nonlinear and takes into account hydraulic phenomena and water quality
Uplift Modeling in Direct Marketing, Journal of Telecommunications and Information Technology, 2012, nr 2
Get PDFMarketing campaigns directed to randomly selected customers often generate huge costs and a weak response. Moreover, such campaigns tend to unnecessarily annoy customers and make them less likely to answer to future communications. Precise targeting of marketing actions can potentially results in a greater return on investment. Usually, response models are used to select good targets. They aim at achieving high prediction accuracy for the probability of purchase based on a sample of customers, to whom a pilot campaign has been sent. However, to separate the impact of the action from other stimuli and spontaneous purchases we should model not the response probabilities themselves, but instead, the change in those probabilities caused by the action. The problem of predicting this change is known as uplift modeling, differential response analysis, or true lift modeling. In this work, tree-based classifiers designed for uplift modeling are applied to real marketing data and compared with traditional response models, and other uplift modeling techniques described in literature. The experiments show that the proposed approaches outperform existing uplift modeling algorithms and demonstrate significant advantages of uplift modeling over traditional, response based targeting
Video Transmission Using Network Coding, Journal of Telecommunications and Information Technology, 2012, nr 1
Get PDFNetwork coding is a new technique in the field of information theory and coding theory. This emerging technique offers great benefits in the communication networks such as increased throughput and energy savings. In this paper, we evaluate network coding for video transmission scenarios. In these scenarios, the source nodes encode the video packets, while the intermediate nodes implement network coding before forwarding the encoded packets to the end nodes. Finally, the end nodes decode the received packets in order to recovery the original video. H.264/MPEG-4 AVC is used as the video compression standard in this work. We have used the network simulator (NS-2) for our simulations. Our results show that network coding improves the system throughput, reduces the packet loss and improves the video quality in the end nodes
Secured Workstation to Process the Data of Different Classification Levels, Journal of Telecommunications and Information Technology, 2012, nr 3
Get PDFThe paper presents some of the results obtained within the ongoing project related with functional requirements and design models of secure workstation for special applications (SWSA). SWSA project is directed toward the combination of the existing hardware and software virtualization with cryptography and identification technologies to ensure the security of multilevel classified data by means of some formal methods. In the paper the requirements for SWSA, its hardware and software architecture, selected security solution for data processing and utilized approach to designing secure software are presented. The novel method for secure software design employs dedicated tools to verify the confidentiality and the integrity of data using Unified Modeling Language (UML) models. In general, the UML security models are embedded in and simulated with the system architecture models, thus the security problems in SWSA can be detected early during the software design. The application of UML topology models enables also to verify the fundamental requirement for MLS systems, namely the hardware isolation of subjects from different security domains
Perspektywy zagospodarowania widma radiowego w Polsce pod kątem implementacji radia kognitywnego. Telekomunikacja i Techniki Informacyjne, 2012, nr 1-2
Get PDFW artykule przeanalizowano zakresy częstotliwości, które mogą być wykorzystane w systemach radia kognitywnego, przy założeniu obecnych i planowanych przeznaczeń częstotliwości w Polsce (w tym także w kontekście przeznaczeń europejskich) oraz istniejącego planu zagospodarowania poszczególnych zakresów częstotliwości. Analizę przeprowadzono uwzględniając możliwość wprowadzenia sieci radia kognitywnego w wybranych częściach widma, w tym w pasmach licencjonowanych oraz nielicencjonowanych, w sposób scentralizowany lub rozproszony
UML Simulation of a TopologyConfiguration Model, Journal of Telecommunications and Information Technology, 2012, nr 4
Get PDFThe article presents the application of simulation methods for topological models to analyze and design information systems. By using UML extensions and the UAL language it is possible not only to build a topological model for software, but also to perform efficient simulations of topological models. Additionally, it is possible to take into account the restrictive conditions stored in UAL and OCL languages. To execute the simulation the authors used an simulator from IBM. These concepts and methods are illustrated by examples
Multiple Criteria Evaluation and Ranking of Social Penetration of Information Society Technologies, Journal of Telecommunications and Information Technology, 2012, nr 4
Get PDFThe paper presents a comparison of two ways of multiple criteria ranking of social penetration of information society technologies (ICT): the traditional one and the so-called objective ranking, illustrated on the example of Network Readiness Index. It is shown that objective ranking stresses a balanced development more than the traditional one. Another issue presented in this paper is the concept of dynamic ranking, a systematic presentation and prediction of the change of ranking in time. This is illustrated on the example of regions of three European countries: Finland, Italy and Poland
Developing a Ring-Based Optical Network Structure with Glass-Through Nodes, Journal of Telecommunications and Information Technology, 2012, nr 2
Get PDFAn important issue in designing optical transport networks (OTN) is security. The concept of 1+1 protection requires to connect each origin-destination(OD)-pair by at least two node-disjoint paths. In the case of a single edge or node failure, the connection of all OD-pairs is maintained under 1+1 protection. On a ring, 1+1 protection is given naturally. Moreover, on rings, the routing effort is typically decreasing. These observations motivate the investigation of ring structures for OTN. When developing a ring structure for telecommunication networks, several subtasks can be identified. Rings have to be designed, OD-pairs have to be assigned to rings, communication among rings has to be defined, a proper flow routing has to be chosen, and rings have to be dimensioned regarding flow capacity. In this paper, we address the first two issues, namely generation of rings and assignment of OD-pairs to rings. Our approach allows to distinguish active and non-active (glass-through) nodes in OTN. Active nodes are equipped with active routing hardware that weakens the optical signal and has impact on feasible ring lengths. Non-active nodes do not influence the optical signal. Although a consideration of active/non-active nodes is important in ring design, only a few references address this issue. We propose an algorithm for generating random ring candidates. Moreover, we present a mathematical model for the assignment of OD-pairs to rings subject to a feasible choice of active nodes. We test our methods using a case of Deutsche Telekom