Tutoriais
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Alberti, Antônio Marcos; Fernandes, Roulien
Abstract: The Generic Framing Procedure, Virtual Concatenation and the Link Capacity Adjusting Scheme are successful technologies that brought new life to synchronous networks. They facilitated efficient, flexible and robust interconnection of two of the most deployed technologies ever: Ethernet and Synchronous Digital Hierarchy (SDH). The objective of this tutorial is to present an overview of these Ethernet-over-SDH (EoS) technologies, focusing on their performances. We reviewed literature from 2001-2009 and present the main aspects of EoS technologies and performance as well as notable formulations for EoS throughput, efficiency and delay.We reviewed the fundamental evolution steps of both Ethernet and SDH. The paper also covers experimental methodology and scenario configuration for EoS performance evaluation in the laboratory, discusses measured results and compares the presented analytical expressions and calculations with experimental data. An in-depth performance evaluation ofEoS networks is conducted.
Index Terms: Performance, Evaluation, SDH, GFP, LCAS, VCat.
Saraiva Campos, Rafael; Lovisolo, Lisandro
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Abstract: This tutorial presents in detail the main components of radio-frequency fingerprinting methods, also known as DCM (Database Correlation Methods), for mobile station positioning. Those methods can locate legacy terminals, i.e, without any specific location services support. Furthermore, as they are capable of yielding position estimates using measurements from a single reference base station, those methods have a high availability. Those characteristics make DCM suitable alternatives for emergency call positioning in cellular móbile networks and for fallback of more precise methods.
Index Terms: Cellular Mobile Networks, Correlation Database, Radio-Frequency Fingerprints, Radiolocation, Received Signal Strength.
Artigos Científicos
Vergütz, Stéphany; Paschoarelli Veiga, Antônio Cláudio
Abstract: The objective of this study is to evaluate the performance of “Fractal Compression” technique onto mammograms through an association between the objective criteria, provided by Peak Signal Noise Ration (PSNR); and the subjective criteria, given by visual analysis of an expert physician. Visual analysis was performed comparing mammograms compressed to different extents (compression rate) with the original image, where experts classified the compressed images as “unacceptable”, “acceptable”, “good” or “great”. In doing so, the optimal compression rate and PSNR values of mammograms was achieved, where images are considered acceptable according to experts. In order to compare the performance of “Fractal Compression” technique with another compression method, visual analysis was also done on images compressed by JPEG2000 method.
Index Terms: Fractal Image Compression, Mammography, Peak Signal Noise Ratio.
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Figueiredo, Carlos H. S.; Ramos, Glaucio L.; Pereira, Paulo T.; S. Júnior, Moacir; S. Queiroz, Carlos
Abstract: This work describes the basic concepts of electromagnetical theory related to non-ionizing radiation emission levels of the radio base station cellular mobile system based in current research. Research results were compared with norms established by agencies such as National Telecommunication Agency (ANATEL), the International Commission on Non-ionizing Radiation Protection (ICNIRP) and other bodies concerned with health-related studies. A comparison will be shown between radiation levels before and after the installation of a new radio base station.
Index Terms: Non-ionizing radiation, radiofrequency, cellular phone, thermal effects.
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Fernandes Sales, Diego; Gomes Neto, Alfredo
Abstract: This work aims to analyze the RF coverage of a GSM/EDGE network located in João Pessoa, PB, Brazil. It was used PlugData MG100, a low cost GSM/EDGE modem, as an alternative mobile measurement tool. From the Móbile Measurement Reports (MMRs) RF coverage and the handover process are analyzed. This work analyzes only data referent to the serving cell and the two closest neighboring cells. The results were analyzed according to inter and intra-cell handover. It was identified quality of service issues related to the serving cell in the suburban areas. The signal level behavior was satisfactory in the open rural area outstanding the frequency planning aspect.
Index Terms: GSM/EDGE, handover, MMRs, PlugData MG100.
Engenharia Aplicada
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Pimenta Carvalho, Rodrigo; Marcos Alberti, Antônio
Abstract: The search for technologies to develop value-added services in Next Generation Networks created what is being called Information and Communication Technologies convergence or ICT. The success of such convergence will depend on, among other factors, adequately opening NGN capacities to support value-added applications development by IT community. Open APIs such like OSA/Parlay and Parlay X are being considered the “bridges”between both worlds. Despite such APIs, there are other technologies and several possible paths involved in this task. In this scenario, our paper firstly shows how next generation converged networks and its functionalities can be exposed properly to someone else, through Parlay X interfaces, implemented in Web Services-based application gateways. Therefore, this paper cames to fulfil the lack of literature regarding methodology for valueadded applications development in NGN. Secondly, we developed and implemented a Third Party Call Parlay X API inside a Parlay X gateway emulator to demonstrate how useful a gateway emulator could be in order to provide quick and correct design and implementation of NGN applications. Finally, we discuss the results obtained.
Index Terms: Service Creation, Value-Added Services, Web Services, Parlay X and NGN.