Institute of Electron Technology
Biblioteka Cyfrowa Instytutu Łączności / National Institute of Telecomunications: Digital LibraryNot a member yet
2189 research outputs found
Sort by
A Hybrid CPU/GPU Cluster for Encryption and Decryption of Large Amounts of Data, Journal of Telecommunications and Information Technology, 2012, nr 3
Get PDFThe main advantage of a distributed computing system over standalone computer is an ability to share the workload between cores, processors and computers. In our paper we present a hybrid cluster system – a novel computing architecture with multi-core CPUs working together with many-core GPUs. It integrates two types of CPU, i.e., Intel and AMD processor with advanced graphics processing units, adequately, Nvidia Tesla and AMD FirePro (formerly ATI). Our CPU/GPU cluster is dedicated to perform massive parallel computations which is a common approach in cryptanalysis and cryptography. The efficiency of parallel implementations of selected data encryption and decryption algorithms are presented to illustrate the performance of our system
Secure Biometric Verification Station Based on Iris Recognition, Journal of Telecommunications and Information Technology, 2012, nr 3
Get PDFThis paper describes an application of the Zak-Gabor-based iris coding to build a secure biometric verification station (SBS), consisting of a professional iris capture camera, a processing unit with specially designed iris recognition and communication software, as well as a display (LCD). Specially designed protocol controls the access to the station and secures the communication between the station and the external world. Reliability of the Zak-Gabor-based coding, similarly to other wavelet-based methods, strongly depends on appropriate choice of the wavelets employed in image coding. This choice cannot be arbitrary and should be adequate to the employed iris image quality. Thus in this paper we propose an automatic iris feature selection mechanism employing, among others, the minimum redundancy, maximum relevance (mRMR) methodology as one, yet important, step to assess the optimal set of wavelets used in this iris recognition application. System reliability is assessed with approximately 1000 iris images collected by the station for 50 different eyes
Analysis and Modeling of Domain Registration Process, Journal of Telecommunications and Information Technology, 2012, nr 2
Get PDFThe paper presents analysis of the domain name reservation process for the polish .pl domain. Two models of various time scale are constructed and finally combined to build long range high resolution model. The results of prediction are verified using real data
Integrated Routing and Network Flow Control Embracing Two Layers of TCP/IP Networks – Methodological Issues, Journal of Telecommunications and Information Technology, 2012, nr 2
Get PDFA cross-layer network optimization problem is considered. It involves network and transport layers, treating both routing and flows as decision variables. Due to the non-convexity of the capacity constraints, when using Lagrangian relaxation method a duality gap causes numerical instability. It is shown that the rescue preserving separability of the problem may be the application of the augmented Lagrangian method, together with Cohen’s Auxiliary Problem Principle
Design and Implementation of an Embedded System for Ambulatory Cardiac Monitoring, Journal of Telecommunications and Information Technology, 2012, nr 1
Get PDFCardiac monitoring in the environment of the subject is one of the major fields of telemedicine. In this paper we present a prototype of embedded system for acquisition, storage, display on LCD or PC and transfer via GSM alarm warning in case of arrhythmias, which allows a great opportunity for rapid intervention of the physician. In terms of hardware, we have designed and implemented our system with a modular approach to facilitate development and debugging. Thus the system comprises three modules: analog module, digital module microcontroller-based for certain pretreatment, and a GSM communication module. Of course, there is appropriate software behind the material described. The system has the following features: low cost, ease to implement and versatility
Recognizing Sets in Evolutionary Multiobjective Optimization, Journal of Telecommunications and Information Technology, 2012, nr 1
Get PDFAmong Evolutionary Multiobjective Optimization Algorithms (EMOA) there are many which find only Paretooptimal solutions. These may not be enough in case of multimodal problems and non-connected Pareto fronts, where more information about the shape of the landscape is required. We propose a Multiobjective Clustered Evolutionary Strategy (MCES) which combines a hierarchic genetic algorithm consisting of multiple populations with EMOA rank selection. In the next stage, the genetic sample is clustered to recognize regions with high density of individuals. These regions are occupied by solutions from the neighborhood of the Pareto set. We discuss genetic algorithms with heuristic and the concept of well-tuning which allows for theoretical verification of the presented strategy. Numerical results begin with one example of clustering in a single-objective benchmark problem. Afterwards, we give an illustration of the EMOA rank selection in a simple two-criteria minimization problem and provide results of the simulation of MCES for multimodal, multi-connected example. The strategy copes with multimodal problems without losing local solutions and gives better insight into the shape of the evolutionary landscape. What is more, the stability of solutions in MCES may be analyzed analytically
Who is Asking and for What: WHOIS Traffic Analysis, Journal of Telecommunications and Information Technology, 2012, nr 4
Get PDFThe paper presents analysis of WHOIS requests for 13-month period. Both requestor address and the domain name being requested are analyzed, showing that WHOIS traffic can be roughly classified into systematic scanning of domain names and individual low-volume activity, mostly targeting very popular names. The comparison of requested names with standard dictionary entries reveals typical mutations for registered names, and mutations performed by scanning automata. As most popular names in WHOIS coincide with standard top website ranks, the ways of utilizing WHOIS data for the benefit of Internet community as a whole, are proposed
Effective Design of the Simulated Annealing Algorithm for the Flowshop Problem with Minimum Makespan Criterion, Journal of Telecommunications and Information Technology, 2012, nr 2
Get PDFIn this paper we address the n-job, m-machine flowshop scheduling problem with minimum completion time (makespan) as the performance criterion. We describe an efficient design of the Simulated Annealing algorithm for solving approximately this NP-hard problem. The main difficulty in implementing the algorithm is no apparent analogy for the temperature as a parameter in the flowshop combinatorial problem. Moreover, the quality of solutions is dependent on the choice of cooling scheme, initial temperature, number of iterations, and the temperature decrease rate at each step as the annealing proceeds. We propose how to choose the values of all the aforementioned parameters, as well as the Boltzmann factor for the Metropolis scheme. Three perturbation techniques are tested and their impact on the solutions quality is analyzed. We also compare a heuristic and randomly generated solutions as initial seeds to the annealing optimization process. Computational experiments indicate that the proposed design provides very good results – the quality of solutions of the Simulated Annealing algorithm is favorably compared with two different heuristics
Diffusion in Networks, Journal of Telecommunications and Information Technology, 2012, nr 2
Get PDFIn this paper a concept of method and its application examining a dynamic of diffusion processes in networks is considered. Presented method was used as a core framework for system CARE (Creative Application to Remedy Epidemics)
O procesach konsolidacji na rynku komunikacji elektronicznej w Polsce. Telekomunikacja i Techniki Informacyjne, 2012, nr 1-2
Get PDFArtykuł opisuje fuzje firm telekomunikacyjnych i medialnych oraz ważne znaczenie tych zmian dla rozwoju polskiego rynku komunikacji elektronicznej. Szczególnie podkreślono zakup firmy telekomunikacji komórkowej Polkomtel dokonanej przez holding Z. Solorza-Żaka i znaczenia tego wydarzenia dla wdrożenia systemu LTE w Polsce