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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.
111

Voice quality evaluation methods and means for mobile communications / Balso kokybės vertinimo metodai ir priemonės mobiliojo ryšio sistemoms

Guršnys, Darius 19 November 2008 (has links)
Thesis presents the research of voice frame losses in the GSM. The possibility of evaluation of quality of short duration signals using PESQ algorithm is analysed. New method for preparation of short duration signals for PESQ measurements is proposed. Original method based on quality classes for voice quality evaluation in mobile communications is presented. / Disertacijoje nagrinėjami GSM kanale vykstantys balso paketų praradimai. Nagrinėjama galimybė vertinti trumpų balso segmentų kokybę PESQ algoritmu. Pasiūlomas naujas, mažos trukmės balso signalų kokybės vertinimo PESQ algoritmu metodas. Pristatomas originalus balso kokybės vertinimo metodas mobiliojo ryšio sistemoms, paremtas balso kokybės klasėmis.
112

An?lise de Handover inter e intra-c?lula em um sistema de telefonia celular atrav?s de m?todo de medi??o simplificado

Sales, Diego Fernandes 12 September 2009 (has links)
Made available in DSpace on 2014-12-17T14:55:38Z (GMT). No. of bitstreams: 1 DiegoFS.pdf: 4121922 bytes, checksum: 12733aecf16cb4251d84ab4d4f8172a2 (MD5) Previous issue date: 2009-09-12 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This dissertation has the purpose to present a portable device named PlugData MG100G, equipped with a cellular module, to analyze the radiofrequency coverage in a GSM network situated in Jo?o Pessoa city, state of Para?ba, at four distinct regions. The equipment, originally, was developed to be used in fixed environments, so it was adapted so that it could be used in conditions of mobility. From the Mobile Measurement Reports (MMRs) RF coverage and the handover process are analyzed. The MMRs enable the identification of the serving cell and the list of the closest neighboring cells monitored by the mobile. This work analyses only data referent to the serving cell and the two closest neighboring cells. Inter-cell and intra-cell handovers are identified. The frequency planning and quality of service offered by the network related to the regions are discussed as well / Esta disserta??o apresenta a aplica??o de um aparelho port?til, PlugData MG100G, equipado com um m?dulo celular, para an?lise de cobertura de radiofreq??ncia em uma rede GSM na cidade de Jo?o Pessoa - PB em quatro regi?es distintas. O equipamento, originalmente, foi criado para uso em ambientes fixos, e para isso, tornou-se necess?ria sua adapta??o para que fosse utilizado em condi??es de mobilidade. A an?lise de RF ? feita atrav?s do Mobile Measurement Reports (MMRs) que s?o usados com prop?sitos de avaliar o handover na rede. Por interm?dio do Measurement Reports ? poss?vel identificar a c?lula que serve o m?vel e uma lista de c?lulas vizinhas mais pr?ximas monitoradas pelo pr?prio m?vel. Neste trabalho s?o analisados apenas os dados referentes ? c?lula servidora e ?s duas c?lulas vizinhas mais pr?ximas. Verificam-se tanto handovers inter c?lulas (entre c?lulas) como handovers intra c?lulas (no interior das c?lulas). Atrav?s dos resultados obtidos pode-se fazer uma an?lise em rela??o ao planejamento de freq??ncias criado para as regi?es onde as medidas foram realizadas e ? qualidade de servi?o oferecida pela rede
113

TSADA - Sistema de telemetria redundante e tolerante a falhas utilizando tecnologia GSM/GPRS e Zigbee / TSADA - Redundant and fault-tolerant telemetry system techologies using GSM/GPRS and Zigbee

Santos, Fernando Beux dos 22 September 2010 (has links)
This work deals with a telemetry system for agricultural mechanization, using GSM / GPRS and ZigBee Radio Frequency. The whole system is a mechanism for collecting and transmitting data at one point moving to a fixed basis, with a system integration and validation. The system gives priority to transmit GSM / GPRS, permitting as an alternative transmission over ZigBee, controlled common mechanism for failure detection, in case of loss of the GSM / GPRS connection the alternative transmission begins, as the system tries to establish a new connection with the priority transmission , thus making the transmission system redundant. The results were satisfactory as the system ensured the transmission of data with fault tolerance and redundantly in remote locations and different reliefs. / O presente trabalho aborda a pesquisa e o desenvolvimento de um sistema de telemetria para a mecanização agrícola e utiliza tecnologia de transmissão de dados sobre telefonia móvel, GSM/GPRS e Rádio Frequência, através do Zigbee. O sistema como um todo consiste em um mecanismo de coleta e transmissão de dados em um ponto móvel para uma base fixa, com uma forma de integração e validação dos dados. O sistema dá prioridade para a transmissão GSM/GPRS e deixa como alternativa a transmissão por ZigBee, controlado por um mecanismo de detecção de falhas que, em caso de perda da conexão do GSM/GPRS, começa a transmissão alternativa, enquanto o sistema tenta restabelecer uma conexão com a transmissão prioritária e torna o sistema de transmissão redundante. Os resultados alcançados foram satisfatórios pois o sistema garantiu a transmissão dos dados com tolerância a falhas e de forma redundante em locais remotos e de relevos diferenciados.
114

Modul elektrické zabezpečovací ústředny s komunikátorem GSM / Module of electronic security central with GSM communicator

Dokulil, Zdeněk January 2010 (has links)
The aim of this diploma thesis is to design and manufacture a small modular burglar alarm control panel with an emphasis on GSM communication functions. The first part of the thesis discusses history of control panels from the first attempts to present technologies. Also a classification of wired and wireless systems is defined. The second part contains an general proposal of the GSM-enabled panel design and description of the circuit. SIM 300C module has been chosen as a GSM terminal device. The final part contains description of key parts of the firmware and a detailed manual for end users. The proposed design has been realized and succesfully tested.
115

Systém pro řízení stínicí a vytápěcí techniky v budově / The System for Controlled Heating and Roller Blinds in the Building

Brudný, Tomáš January 2010 (has links)
The object of this project was to develop a device, which would by use to coordinate or control device wireless. The system divided to several independent devices, which assure high comfort for the user. The basic unit contains of touch panel which allow the user to control the system. The second unit is used for communication the system with GSM net. The third unit is used to coordinate the system from a PC. This unit makes possible data collection and their evaluation. This unit can as well control and coordinate any devises in the system. Part and parcel of this system are units which are used to drive the end consumers. The hole system is powered from a instead powers supply which is managed from a microprocessor. These devices make it possible, to the system to work without line voltage. The system is designed modular, so in the future it is possible to expand the system of others peripherals.
116

Včelařská váha / Hive Scale

Hlaváč, Pavel January 2015 (has links)
This thesis deals with the development of an affordable hive scale which will be placed under the hive. The scale is expected to show the user all necessary information via the GSM mobile network. Incoming SMS message informs the user about the current weight and moisture. The information obtained can be displayed graphically in the application for android phones.
117

Addressing non-conformities in a ERTMS implementation : Collecting non-conformities in ERTMS simulation and analyzing their management via a database

Ndikuriyo, Laurier January 2015 (has links)
The European Rail Traffic Management System (ERTMS) aims to standardize train control command and communication systems in Europe. The main goal of its introduction is to develop trans-European railway traffic and increase competition. The two main components of ERTMS are European Train Control System (ETCS), which is an Automatic Protection System (ATP), and GSM–Railway (GSM-R).GSM-R is a radio transmission system that provides data and voice communication between the train and trackside facilities. Classical rail signaling systems are recommended to be updated to meet these standards. This master’s thesis is conducted in cooperation with Bombardier Transportation (BT), the rail equipment division of firm Bombardier Inc. It explores a part of ERTMS implementation and aims to identify its failures/non-conformities during its simulation. A non-conformity is any deviation or nonfulfillment of a requirement involving a product manufactured at BT. This thesis first collects failures/non conformities in test sessions and stores it into databases. A failure/non-conformity is processed by many engineers from the time it is detected in a test until it is resolved.  This thesis project seeks to investigate the exchange and the management of failures in both the tools and databases, together with analyzing the interaction between engineers through tools and databases. Non conformities detected during the simulation is stored in databases. The goal is to utilize this data to highlight parts of ERTMS implementation which generate most of non-conformities during the simulation. This information indicates to engineers where to focus and act in order to improve Bombardier Transportation’s products. This thesis successfully simulated a part of ERMS implementation. Several different tests cases were conducted and seven non-conformities were detected. These non-conformities were used to investigate and analyze the process of managing failures in tools and databases. This thesis proved that the exchange and the management of information about non-conformities was inefficient and time consuming. In the worst case, non-conformities were completely lost during this process. Several corrective actions were proposed in order to improve the handling of non-conformities. / Europeiskt styrsystem för järnvägstrafik (ERTMS) har i mål att till standardisera tåglednings- och kommunikationssystem i Europa. Den huvudsakliga målsättningen är att utveckla transeuropeiska järnvägstrafiken och öka konkurrensen. De två viktigaste komponenterna i ERTMS är European Train Control System (ETCS) och GSM-Railway (GSM-R). ECTS är Automatisk Protection System (ATP). GSM-R är en radiotransmissions system som tillhandahåller data och röstkommunikation mellan tåg och markanläggningar. Klassisk järnväg signalsystem rekommenderas att uppdatera för att uppfylla dessa standarder. Denna magisteruppsats sker i samarbete med Bombardier Transportation (BT) som är järnvägsutrustning uppdelningen av företaget Bombardier Inc. Det skall utforskas en del av ERTMS implementering och som syftar till att identifiera sina avvikelser och misslyckanden under sin simulering. Denna avhandling samlar först med misslyckanden/icke-avvikelser i testsessioner och lagrar det i databaser. Ett icke-avvikelser är någon icke uppfyllande av ett krav som medför en produkt som tillverkas vid BT. Ett misslyckande/icke-avvikelse behandlas av många ingenjörer från den tidpunkt då den upptäcks i ett test tills det är löst. Detta examensarbete syftar till att undersöka utbytet och hanteringen av brister i både verktyg och databaser, tillsammans med att analysera samspelet mellan ingenjörer via verktyg och databaser. De upptäckta enhetligheterna under simuleringen lagras i databaser. Målet är att utnyttja dessa data för att markera delar av ERTMS implementering som genererar merparten av avvikelser under simuleringen. Denna information indikerar att ingenjörer var att fokusera och agera i syfte att förbättra Bombardier Transportations produkter. Denna avhandling har med framgång simulerat en del av ERMS implementering. Flera olika tester fall genomfördes och sju avvikelser upptäcktes. Dessa avvikelser användes för att undersöka och analysera processen för att hantera misslyckanden inom verktyg och databaser. Avhandlingen visade att utbyte och hantering av information om avvikelser var ineffektivt och tidsödande. I värsta fall, var avvikelser helt förlorad under denna process. Flera korrigerande åtgärder föreslogs för att förbättra hanteringen av avvikelser.
118

Développement d'une méthode de géolocalisation à l'intérieur de bâtiments par classification des fingerprints GSM et fusion de données de capteurs embarqués / Practical indoor localization system using GSM fingerprints and embedded sensors

Tian, Ye 13 February 2015 (has links)
L’objet de cette thèse est l’étude de la localisation et de la navigation à l’intérieur de bâtiments à l’aide des signaux disponibles dans les systèmes mobiles cellulaires et, en particulier, les signaux GSM.Le système GPS est aujourd’hui couramment utilisé en extérieur pour déterminer la position d’un objet, mais les signaux GPS ne sont pas adaptés à la localisation en intérieurIci, la localisation en intérieur est obtenue à partir de la technique des «empreintes» de puissance des signaux reçus sur les canaux utilisés par les réseaux GSM. Elle est réalisée à l’échelle de la pièce. Une classification est effectuée à partir de machines à vecteurs supports et les descripteurs utilisés sont les puissances de toutes les porteuses GSM. D’autres capteurs physiques disponibles dans les téléphones portables fournissent des informations utiles pour déterminer la position ou le déplacement de l’utilisateur. Celles-ci, ainsi que la cartographie de l’environnement, sont associées aux résultats obtenus à partir des «empreintes» GSM au sein de filtres particulaires afin d’obtenir une localisation plus précise, et sous forme de coordonnées continues.Les résultats obtenus montrent que l’utilisation des seules empreintes GSM permet de déterminer la pièce correcte dans 94% des cas sur une durée courte et que les performances restent stables pendant plusieurs mois, de l’ordre de 80%, si les données d’apprentissage sont enregistrées sur quelques jours. L’association de la cartographie du lieu et des informations issues des autres capteurs aux données de classification permettent d’obtenir les coordonnées de la trajectoire du système mobile avec une bonne précision et une bonne fiabilité. / GPS has long been used for accurate and reliable outdoor localization, but it cannot operate in indoor environments, which suggests developing indoor localization methods that can provide seamless and ubiquitous services for mobile users.In this thesis, indoor localization is realized making use of received signal strength fingerprinting technique based on the existing GSM networks. A room is defined as the minimum location unit, and support vector machine are used as a mean to discriminate the rooms by classifying received signal strengths from very large number of GSM carriers. At the same time, multiple sensors, such as accelerometer and gyroscope, are widely available for modern mobile devices, which provide additional information that helps location determination. The hybrid approach that combines the GSM fingerprinting results with mobile sensor and building layout information using a particle filter provides a more accurate and fine-grained localization result.The results of experiments under realistic conditions demonstrate that correct room number can be obtained 94% of the time provided the derived model is used before significant received signal strength drift sets in. Furthermore, if the training data is sampled over a few days, the performance can remain stable exceeding 80% over a period of months, and can be further improved with various post-processing techniques. Moreover, including the mobile sensors allows the system to localize the mobile trajectory coordinates with high accuracy and reliability.
119

10 portový GSM reléový spínač s GUI / 10 port GSM relay switch with GUI

Bartulec, Tomasz January 2008 (has links)
System hardware and software design for a GSM switch with ten switching outputs, controlled via SMS. Description of used GSM module and its properties, feasibility and requirements, design and description of supply circuits for module outputs to relay outputs decoding, plug-in realisation of outputs. GSM module application software creation, remote SMS control requests implementation, sender's phone number check and information about completed requests by call-backs. Adding AT command to set up device. Development of web server providing control of switch throught Internet browser, solving communication between server and device, and data management. Testing of created SW and evaluation of final design from aspects of usage.
120

Análise metodológica do posicionamento relativo através do GNSS e suas aplicações na engenharia: uso da técnica RTK/GSM. / Relative positioning metodology analysis through GNSS and its applications in engineering: use of RTK/GSM technique.

Guandalini, Marcos 12 June 2012 (has links)
A utilização dos sistemas de navegação global por satélite, conhecidos pela sigla GNSS (Global Navigation Satellite System), cresceu vertiginosamente durante a última década. Atualmente, os receptores GNSS são ferramentas seguras, eficientes e altamente produtivas para a realização de observações aos satélites, possibilitando determinar coordenadas geodésicas sobre a superfície terrestre. As ferramentas e tecnologias disponíveis no mercado são de essencial importância no desenvolvimento eficiente dos projetos de engenharia. No entanto, o domínio das técnicas de trabalho e o conhecimento profundo de todos os métodos de execução são os principais obstáculos para a introdução de uma nova metodologia em projetos de engenharia. Este trabalho tem por objetivo esclarecer e testar a associação dessa tecnologia com o uso da telefonia celular, em especial com a utilização da conexão GSM (Global System for Mobile Communication) / GPRS (General Packet Radio Service), disponíveis no Brasil. O posicionamento preciso em tempo real tradicionalmente envia as observações de fase da onda portadora entre o receptor GNSS base e móvel através de frequências de rádio. Isso possibilita a determinação de coordenadas geodésicas e topográficas instantaneamente. Entretanto, obstáculos como áreas de relevo acidentado, edificações ou a baixa potência do rádio que envia os sinais fazem com que a comunicação entre os equipamentos seja interrompida com a perda frequente da solução instantânea. Apesar disso, este método de trabalho está consagrado como o mais produtivo, mantendo precisões topográficas, sendo que superar as restrições citadas seria uma inovação na área de Geodésia e Topografia. Com o avanço de tecnologias correlatas, criou-se uma nova maneira de enviar as observações de fase utilizando a conexão GSM através do pacote de dados GPRS. A conexão GSM é aplicada na tecnologia móvel padrão, que se tornou a mais popular para telefones celulares, de fácil acesso a qualquer usuário. Adequando o tradicional protocolo RTCM (Radio Technical Commission for Maritime Services) em um formato capaz de ser transmitido por GPRS, desenvolveu-se assim o serviço NTRIP (Network Transport of RTCM via Internet Protocol). Com esta nova concepção da conexão GSM/GPRS é possível realizar levantamentos com a técnica RTK (Real Time Kinematic) com vetores de até 100 km, mantendo as precisões atingidas com a metodologia atual de pós-processamento. Os tipos de equipamentos, os limites de distâncias e a qualidade dos dados obtidos estão sendo discutidos nesta pesquisa e analisados de forma a verificar os resultados atingidos em termos de precisão e acurácia. / The use of Global Navigation Satellite System has dramatically grown over the last decade. Currently, GNSS receivers are secure, efficient and highly productive for carrying out observations for the geodetic coordinates determination on the Earth\'s surface. The tools and technologies available on the market are essential in the establishment of engineering projects. However, the total knowledge of the techniques and the total domain of the execution methods are the first obstacles to the full incorporation of the technology in the engineering projects. This work is to clarify and to teste the technology described in this dissertation related to the facilities of cell phone coverage, particularly the GSM/GPRS connection able to be used in Brazil. The precise positioning in real-time traditionally involves the transmission of phase measurements between base and rover GNSS receivers; this is traditionally carried out through radio frequencies. This allows determining geodetic and topographic coordinates instantaneously. However, obstacles like accident topography terrain, buildings or low power of radio basis transmission, provoke constant interruptions in the communication among the radios and the consequent losing of the instant solution. Nevertheless, this methodology is the most productive for a centimetric accuracy; so the major challenge in geodetic positioning is to overcome the mentioned difficulties. With the high development of technologies related to mobile phone, a new way to transmit the observations using the GSM/GPRS connection was created. The GSM connection is a standard mobile technology, the most popular for cell phones, which became of easy access to any person. The traditional RTCM protocol in a convenient format can be transmitted by GSM/GPRS connection which is known as NTRIP service, becoming a full digital communication system. As of this new concept, it is possible to note vectors up to 100 km in RTK technique employment with the same high quality measurement. The equipment characteristics, distance limits and quality of the data recorded have been discussed and analyzed here in order to verify whether the results can achieve the necessary precision and accuracy.

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