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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Real Time Positioning; Construction and implementation of a GPS-Communicator. / Realtidspositionering; Utveckling av en GPS-kommunikator.

Darnell, Christian, Wilczoch, Christian January 2002 (has links)
The first half of the Masters thesis is the result of a survey made on the behalf of the Swedish company KORDAB International AB. The survey includes an overview of different positioning systems and some wireless communication techniques available on the market today. Positioning systems discussed are GPS, DGPS, AGPS and GSM positioning. Mobile Internet connections through mobile phones and communication through radio modems are mentioned and described as examples of wireless communication techniques. Examples of techniques described are HSCSD, GPRS, UMTS and MOBITEX. KORDAB is in the starting blocks to implement a real time positioning feature into their own technical information system GEOSECMA. This survey will give them a base which will help them to decide on which system to use for this feature. The second half of the thesis includes parts concerning a prototype made to exemplify how KORDAB could implement the real time positioning feature into GEOSECMA. The NMEA 0183 protocol, reference systems and transformation are described to give the necessary background knowledge for the construction and functionality of the prototype. The prototype is a GPS-communicator made as an interface between a GPS-receiver and GEOSECMA and its functionality is also described in this second half of the thesis. Feasible applications are also discussed to show the possibilities real time positioning gives. One application discussed is “Zoom and Auto highlighting”. This application is designed to help user of GEOSECMA to zoom in the map and highlighting the nearest object at current location.
232

Real Time Positioning; Construction and implementation of a GPS-Communicator. / Realtidspositionering; Utveckling av en GPS-kommunikator.

Darnell, Christian, Wilczoch, Christian January 2002 (has links)
<p>The first half of the Masters thesis is the result of a survey made on the behalf of the Swedish company KORDAB International AB. The survey includes an overview of different positioning systems and some wireless communication techniques available on the market today. Positioning systems discussed are GPS, DGPS, AGPS and GSM positioning. Mobile Internet connections through mobile phones and communication through radio modems are mentioned and described as examples of wireless communication techniques. Examples of techniques described are HSCSD, GPRS, UMTS and MOBITEX. KORDAB is in the starting blocks to implement a real time positioning feature into their own technical information system GEOSECMA. This survey will give them a base which will help them to decide on which system to use for this feature. </p><p>The second half of the thesis includes parts concerning a prototype made to exemplify how KORDAB could implement the real time positioning feature into GEOSECMA. The NMEA 0183 protocol, reference systems and transformation are described to give the necessary background knowledge for the construction and functionality of the prototype. The prototype is a GPS-communicator made as an interface between a GPS-receiver and GEOSECMA and its functionality is also described in this second half of the thesis. Feasible applications are also discussed to show the possibilities real time positioning gives. One application discussed is “Zoom and Auto highlighting”. This application is designed to help user of GEOSECMA to zoom in the map and highlighting the nearest object at current location.</p>
233

Algoritmo de alocação dinâmica de largura de faixa para redes de comunicação móvel celular / Dynamic bandwidth allocation algorithm for mobile communication networks

Eduardo Martinelli Galvão de Queiroz 28 March 2008 (has links)
O crescente aumento da demanda de tráfego nas redes celulares vem aumentando a necessidade de uma melhor utilização dos recursos do sistema, já que sua expansão é custosa. Nas estações rádio base (ERB), a disponibilidade de largura de faixa de freqüências é limitada e desta maneira, em uma rede de comunicação móvel celular, o controle de admissão de chamadas exerce grande influência no desempenho do sistema, pois determina a utilização de banda das ERBs e se uma determinada quantidade de recursos (banda) será alocado ou não para uma determinada chamada. O desempenho da rede pode ser atrelado a determinados parâmetros, como a probabilidade de bloqueio de novas chamadas, probabilidade de bloqueio de chamadas handoff e a utilização de banda da rede. Este trabalho propõe um controle de admissão de chamadas que, no atendimento de uma chamada, faz o empréstimo de banda de chamadas em andamento na célula no caso de banda insuficiente. O sistema adota um mecanismo heurístico que determina a banda disponível para novas chamadas conforme os valores de certos parâmetros do sistema. O empréstimo de banda é realizado em chamadas em andamento nas células até níveis mínimos estabelecidos para cada tipo de chamada, que se diferenciam pelas necessidades de banda de cada uma. O algoritmo foi aplicado às bandas e características de uma rede de terceira geração (3G), que possui chamadas de voz, videoconferência, interação multimídia, e-mail, downloads e transferência de arquivos e a uma rede GSM/GPRS (global system for mobile communications/ general packet radio service), que possui chamadas de voz e de dados. Os resultados mostram melhorias na probabilidade de bloqueio de novas chamadas, probabilidade de bloqueio de handoff e na utilização de banda do sistema. / The recent growth in traffic loads in cellular networks has seen the need for a better use of system resources as its expansion is expensive. In the base transceiver station (BTS), the bandwidth availability is limited. Thus, in cellular networks the call admission control greatly influences the system performance because it determines the bandwidth use of the BTSs and if an amount of resources will or will not be allocated to a call. The network performance can be evaluated by parameters such as blocking probability of new calls, dropping probability of handoff calls and bandwidth use. This work proposes a call admission control that carries out the bandwidth borrowing when a call arrives and there is not enough bandwidth. The system makes use of a heuristic mechanism that determines the available bandwidth for the new calls according to some parameter values of the system. The bandwidth borrowing is applied to the cell ongoing calls until the minimum levels for each type are met. The algorithm was applied to the bandwidths and characteristics of a third generation cellular network, which supports voice calls, videoconference, multimedia interaction, e-mails, downloads and file transfers. It was also applied to a GSM/GPRS (global system for mobile communications/ general packet radio service), which supports voice and data calls. The results show improvements in the blocking probability of new calls, dropping probability of handoff calls and in the bandwidth use of the system.
234

Etudes des modèles d'implémentation des opérateurs de réseaux mobiles virtuels / Study of implementation models of mobile virtual network operator (MVNO)

Cuvelliez, Charles 09 March 2006 (has links)
This thesis addresses the phenomena of Mobile Virtual Network Operators (MVNO): often MVNO do not come from the telecom sector but they rent the network to mobile operators to become fully mobile operators on their own. So they compete directly not only with the other mobile operators but also with their hosting mobile operator.<p><p>Hosting MVNOs, supporting them from both operational and commercial perspectives are new challenges for the mobile operators: they have to set up a specific internal organization because they used to be a vertically integrated industrial structure. All of this represents tremendous changes for them.<p><p>This thesis describes first the strategic models for hosting MVNOs. The regulatory aspects, that are an essential driver for the liberalization of network economies, are then analyzed. The key point is: are the MVNO able to increase the efficiency and competitiveness of mobile markets.<p><p>Another important aspect is the modelling of a mobile network: the MVNOs will use some components while other components are unuseful for them. Without such model, it is impossible to derive the right costs and price to be charged to the MVNO in order to have a win win industrial model for both the MVNO and its hosting operator.<p><p>A case study of a corporate MVNO focusing on needs of multinationals is analyzed. Such case study describes all the steps for an economic actor to become MVNO from scratch. Such MVNO are not yet present although there is a market demand.<p>The last chapter makes a comparative study of the MVNO markets in the European Union.<p><p>Cette étude aborde le phénomène des opérateurs de réseaux mobiles virtuels ;il s’agit d’acteurs économiques - parfois sans lien aucun avec les télécommunications - qui louent le réseau d’opérateurs mobiles ;ils deviennent à leur tour opérateurs à part entière au point de devenir concurrent non seulement des autres opérateurs mobiles mais aussi de l’opérateur mobile qui leur a loué une partie de son réseau.<p><p>L’hébergement technique de l’opérateur virtuel, son support opérationnel et commercial, l’organisation que doit mettre en place l’opérateur mobile pour héberger son opérateur virtuel afin de partager avec lui son réseau sont des nouveaux défis auxquels les opérateurs mobiles, habitués à être des structures industrielles totalement intégrées verticalement, font face pour la première fois.<p><p>Cette étude traite des modèles d’implémentation des opérateurs de réseaux mobiles virtuels :elle aborde d’abord les aspects stratégiques qui fixent le cadre pour les opérateurs mobiles qui veulent ou sont forcés à héberger des opérateurs virtuels. Les aspects réglementaires, une composante essentielle des économies de réseaux en voie de libéralisation, sont ensuite étudiés, en particulier, comment les opérateurs virtuels peuvent contribuer à améliorer la compétitivité et la libéralisation de ces marchés.<p><p>L’étude modélise ensuite le réseau d’un opérateur mobile de façon à mettre en évidence les éléments à partager qui seront utilisés par l’opérateur virtuel. Cette modélisation est essentielle pour déterminer le coût de l’hébergement et du partage du réseau de façon à créer les conditions de rentabilité de ce modèle d’opérateur virtuel.<p><p>On aborde enfin un cas d’étude d’un candidat à devenir opérateur de réseau mobile virtuel qui souhaite répondre à la demande transnationale des grandes entreprises. Ce type d’opérateur virtuel est encore inexistant de nos jours.<p>Enfin, nous terminons par une étude comparée de la situation des opérateurs mobiles virtuels à travers l’Union Européenne.<p><p> / Doctorat en sciences appliquées / info:eu-repo/semantics/nonPublished
235

GSM monitorovací systém pro staré lidi / GSM monitoring system for elderly poeple

Ďurík, Maroš January 2014 (has links)
The work deals with design of system for monitoring elderly people. The final product of this thesis will be used to ensure protection of old person´s health. The device will also remind water regime, taking of medicine, measure gas concentration and it will make an emergency call or send an emergency SMS. It will inform an old person about time and date and it will also be working in case of power fail.
236

Metodika využívání e-bankingu a elektronických katalogů / Procedure of using e-banking and e-catalogues

Neumanová, Radka January 2008 (has links)
This diploma work deals with using e-banking and e-catalogues problems. First part of the diploma work describes e-banking development including actual forms of e-banking. Next part deals with connection between e-catalogues and e-banking. In the last part of the diploma work there is described concept of the procedure of using e-banking and e-catalogues and the practical ways of using the procedure.
237

Smart Metering vodovodu v areálu stavební fakulty VUT v Brně / Smart Metering of Water Supply System at Campus of Faculty of Civil Engineering BUT

Černíková, Eva January 2015 (has links)
The aim of this thesis is to perform an analysis of possibilities and benefits of installing the Smart Water Metering technology at campus of Faculty of Civil Engineering, Brno University of Technology. The main goal was to provide specific solutions of Smart Metering systems from different companies. One part of this thesis is dedicated to a detailed analysis of a water consumption measurement campaign that took place at the beginning of this academic year using dataloggers. Real-time flow rate and consumed volume was recorded every five minutes. Therefore it was possible to determine water consumption patterns during the day and also tell the minimum, maximum and average flow rate in different parts of the campus. Thanks to these measurements, irregular water consumption during the night was observed. This would not have been easily detected without recording real-time data. This system of recording real-time flow rates with dataloggers is considered to be suitable for the needs of faculty. Thanks to a GSM module, recorded values are sent to an FTP server once a day. From there the data can be downloaded to any kind of analysis software. Installation of Smart Water Metering technology at campus of Faculty of Civil Engineering would be beneficial for both operation of the water supply network and also for purposes of an academic research.
238

ACCESSIBLE MOBILE COMMUNICATION FOR PEOPLE WITH DISABILITIES

Nguyen, Toan Hieu, toan.nguyen@novita.org.au January 2006 (has links)
People with disabilities are both functionally and socially disadvantaged and the lack of access to mobile communication technology adds to their disadvantage. Changes and benefits we have seen in our society with the advent of mobile phones and associated electronic communication for people without disabilities have not migrated to people with disabilities. The comprehensive communication capability of a mobile phone can enable users anywhere to independently access a very wide range of communication, information and control systems and services. This research has addressed the key accessibility issues faced by people with disabilities who need or want to use the mobile phone for voice and data communication. The research revealed that: � there exist accessible features on mobile phones that can better assist people with disabilities in using the phone; � through education and training, people with disabilities can develop or be provided with effective and efficient ways to access and use the phone; � current, off-the-shelf telecommunications equipment such as car kits, speakerphone, voice recognition technology, wireless connectivity capability on mobile phones can enable people with disabilities, even severe physical disabilities, to access the telecommunications network and services; and � with a suitable interfacing system in place, Augmentative and Alternative Communication (AAC) device users can operate the phone for voice and data communication, which previously had not been possible. Trials established that people with a range of physical disabilities can use and should have equal access to telecommunications equipment and services. This research has shown that, with the right policies, processes and support through equipment matching, education, training and delivery, current off-the-shelf solutions can help people with disabilities to effectively communicate with other members of our society and to access the same range of information systems and services enjoyed by able-bodied members of the community. An interfacing system has been developed to provide users of AAC technology with the ability to use a mobile phone for voice calls and text messaging (SMS). It is confidently predicted that other features and services on the phone such as speakerphone, digital camera and FM radio, email and internet-based applications, and local or remote appliances and devices, can be controlled via the AAC device. Outcomes and findings have confirmed the main hypothesis of the thesis that, despite very limited mobility, speed, accuracy and vocal communication ability, users will be able to successfully operate the mobile phone itself, and use it for various modes of bidirectional communication with systems to which they choose to connect. The overall outcomes of the research have established that the benefits and usefulness of the mobile phone are so significant that they should become a necessity for people with a disability. It has been successfully demonstrated that, with the proper mechanisms and educational programs in place, the provision of accessible mobile phones for people with disabilities can significantly improve their quality of life through increased range of accessible activities, and will improve their independence, engagement with their peers, safety, security and self-esteem.
239

Couplages algorithmes génétiques et TLM pour la conception des antennes imprimées miniatures

Chu, H.S. 02 June 2004 (has links) (PDF)
Cette étude contribue à la recherche de formes originales et non intuitives d'antennes miniatures. Il s'agit du développement et de l'application d'un code de calcul associant la simulation électromagnétique TLM (Transmission Line Matrix) à un Algorithme Génétique (AG). La partie théorique présente d'une part la méthode TLM et d'autre part les algorithmes génétiques. La méthode TLM, sur calculateur parallèle, permet d'analyser en 3 dimensions des antennes miniatures de formes arbitraires. Ses évolutions successives sont présentées avec l'objectif d'un couplage avec les algorithmes génétiques. Ceux-ci s'inspirent d'une technique d'optimisation stochastique basée sur la sélection naturelle et l'evolution des espèces. Une présentation définissant les grandeurs fondamentales à nos développements est effectuée. Dans la partie suivante, le couplage AG/TLM est décrit. La conception d'antennes, de formes intuitives ou non, est proposée pour deux types d'antennes bien connues, large bande et bi-bande. Il est ensuite propose un micro-algorithme génétique et son couplage avec la TLM (mAG/TLM) permettant d'atteindre une convergence plus rapide vers la solution optimale et d'éviter des convergences prématurées. Le code mAG/TLM a été appliqué à la recherche d'antennes imprimées, pour les normes WLAN2450 et HIPERLAN5250. Plusieurs antennes obtenues, chaque configuration dépend des conditions imposées sur les conditions initiales et sur la définition de la fonction ''objectif'', portant sur l'adaptation. Une étude expérimentale et de comparaisons systématique avec des logiciels commerciaux a été également développée. Enfin, dans la dernière partie, on s'est attache a l'optimisation d'antennes de type PIFA permettant de couvrir plusieurs standards, GSM, DCS, PCS, UMTS ou WLAN. Des résultats originaux sont proposes. En dernier lieu, des antennes filsplaques mono-polaires répondant aux standards WLAN/HIPERLAN2 et UMTS/HIPARLAN2 ont été obtenus.
240

EFFETS NON THERMIQUES DES CHAMPS DE RADIOFREQUENCES SUR LE SYSTEME NERVEUX CENTRAL : ETUDE MULTIPARAMETRIQUE REALISEE SUR LE RAT VIGILE

Crouzier, David 26 April 2006 (has links) (PDF)
DE NOMBREUSES CRAINTES SONT AUJOURD'HUI FORMULEES QUANT A L'INNOCUITE DES CHAMPS DE RADIOFREQUENCES SUR LA SANTE. PARMI CELLES-CI DES PERTURBATIONS DE LA NEUROPHYSIOLOGIE ET PLUS SPECIFIQUEMENT DU SYSTEME CHOLINERGIQUE CENTRAL ONT ETE EVOQUEES. <br />UN MODELE D'ETUDE MULTIPARAMETRIQUE A ETE DEVELOPPE CHEZ LE RAT VIGILE PRESENTANT A LA FOIS UN ASPECT ELECTROPHYSIOLOGIQUE, NEUROCHIMIQUE OBTENU PAR MICRODIALYSE, COMPORTEMENTAL PAR QUANTIFICATION DES ETATS DE VIGILANCE ET THERMOPHYSIOLOGIQUE PAR LE SUIVI DE LA TEMPERATURE CORPORELLE.<br />LORS DE L'EXPOSITION A UN CHAMP ELECTROMAGNETIQUE DE 1,8 GHZ OU 2,45 GHZ POUR DES PUISSANCES ATHERMIQUES, AUCUN EFFET SIGNIFICATIF N'A PU ETRE MIS EN EVIDENCE SUR LA NEUROPHYSIOLOGIE. PARALLELEMENT A CETTE ETUDE, UNE ETUDE DE LA COMPOSITION LIPIDIQUE DU TISSU CEREBRAL ET UNE ETUDE DE SES METABOLITES ONT ETE REALISEES PAR SPECTROSCOPIE RMN. CES ETUDES EGALEMENT N'ONT PAS MONTRE D'EFFETS DES ONDES ELECTROMAGNETIQUES.

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