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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.
61

Sistema de monitoramento remoto baseado em rede de celular GSM/GPRS para gerenciamento de desgaste de pastilha de freio e vibração da torre em aerogeradores

Gruber, Vilson January 2007 (has links)
Com a necessidade da obtenção da informação ser disponibilizada em vários locais simultaneamente, mostrando resultados on-line, faz com que as redes de comunicação de dados estejam cada vez mais presentes no dia-a-dia das pessoas e das empresas obrigando a constante busca por novas técnicas e meios de estabelecer essa comunicação. Disponibilizar sistemas de monitoração, supervisão e controle de dados on-line em máquinas e equipamentos em tempo real, não é uma tarefa nada fácil. Na estratégia de investimento, a escolha apropriada da rede e o meio de estabelecer essa comunicação na integração dos diversos equipamentos distribuídos em locais diferentes (remotos) é um fator importante para o sucesso dos dados que se queiram monitorar. O presente trabalho mostra as tecnologias de comunicação sem fio – Wireless e Celular através de uma pesquisa e estudo de caso feito em Laboratório da UFRGS e Faculdade SATC com a criação de um protótipo de uma interface de aquisição de dados utilizando a rede celular GSM/GPRS para simular a transmissão e recepção de dados para o monitoramento remoto de 02 (duas) variáveis aqui definidas como vibração da torre e desgaste de pastilha de freio em aerogerador de pequeno porte. Os dados aqui estudados mostram resultados que podem ser úteis para qualquer empresa que planeje implantar um sistema de monitoramento remoto através da Rede Celular (GSM/GPRS). Apesar de no experimento ter sido utilizado variáveis de um aerogerador, são mostradas outras aplicações possíveis de monitoramento remoto utilizando-se o canal de comunicação ar. / With the need to obtain the information be made available in several places simultaneously, showing results online, means that the networks of communication of data are increasingly present in the day-to-day of people and businesses requiring the constant search for new techniques and means to establish such communication. Enabling systems for monitoring, surveillance and control of data online in machinery and equipment in real time, nothing is not an easy task. In investment strategy, the choice of appropriate network and the means to establish this communication in the integration of the various equipment distributed in different locations (remote) is an important factor for the success of the data that we want to track. The present work shows the wireless communication technologies-Wireless and Mobile through a search and case study done in the laboratory and UFRGS and SATC College with the creation of a prototype of an interface for data acquisition using the GSM / GPRS cellular network to simulate the transmission and reception of data to the remote monitoring of 02 (two) variables here defined as vibration of the tower and wear of the brake chip in wind power of small. The data studied here show us results that can be useful for any business that plan deploy a system for remote monitoring via the Network Mobile (GSM / GPRS). Although the experiment have used variables of a wind power, are shown other possible applications of remote monitoring using the channel of communication wireless.
62

Cascading Web Services in Mobile Environments : Bridging Wireless and Wired Networks for Data Transactions

Kajtazi, Miranda, Vogel, Bahtijar January 2007 (has links)
Cascading Web Services represent a collection of services offered in a system consisting of multiple devices and multiple interacting platform independent networks. ‘Cascading’ enables Web Services to exploit access in diverse environments without manual intervention. The aim of this thesis is to investigate how Mobile Web Services interact with multiple other Web Services by allowing the generated content to cascade. These services are demonstrated as a technical design solution, in a number of cases within the field of Learning technologies. Communication among devices is preceded using request-response commands by cascading these commands between different Web Services that are self-contained and independent on their context or state. The system signifies a typical Service Oriented Architecture (SOA) based on a distributed system. Cascading Web Services involve multiple transport networks including Bluetooth Technology, GPRS, Wi-Fi, and Wired Networks. Whereas the protocol of this communication is to bridge Wired and Wireless networks for data transactions, specifically from a Bluetooth location-based network. A number of particular cases will be illustrated in the context of ‘educational outdoor activities’, to demonstrate how the system solution works involving users.
63

Sistema de monitoramento remoto baseado em rede de celular GSM/GPRS para gerenciamento de desgaste de pastilha de freio e vibração da torre em aerogeradores

Gruber, Vilson January 2007 (has links)
Com a necessidade da obtenção da informação ser disponibilizada em vários locais simultaneamente, mostrando resultados on-line, faz com que as redes de comunicação de dados estejam cada vez mais presentes no dia-a-dia das pessoas e das empresas obrigando a constante busca por novas técnicas e meios de estabelecer essa comunicação. Disponibilizar sistemas de monitoração, supervisão e controle de dados on-line em máquinas e equipamentos em tempo real, não é uma tarefa nada fácil. Na estratégia de investimento, a escolha apropriada da rede e o meio de estabelecer essa comunicação na integração dos diversos equipamentos distribuídos em locais diferentes (remotos) é um fator importante para o sucesso dos dados que se queiram monitorar. O presente trabalho mostra as tecnologias de comunicação sem fio – Wireless e Celular através de uma pesquisa e estudo de caso feito em Laboratório da UFRGS e Faculdade SATC com a criação de um protótipo de uma interface de aquisição de dados utilizando a rede celular GSM/GPRS para simular a transmissão e recepção de dados para o monitoramento remoto de 02 (duas) variáveis aqui definidas como vibração da torre e desgaste de pastilha de freio em aerogerador de pequeno porte. Os dados aqui estudados mostram resultados que podem ser úteis para qualquer empresa que planeje implantar um sistema de monitoramento remoto através da Rede Celular (GSM/GPRS). Apesar de no experimento ter sido utilizado variáveis de um aerogerador, são mostradas outras aplicações possíveis de monitoramento remoto utilizando-se o canal de comunicação ar. / With the need to obtain the information be made available in several places simultaneously, showing results online, means that the networks of communication of data are increasingly present in the day-to-day of people and businesses requiring the constant search for new techniques and means to establish such communication. Enabling systems for monitoring, surveillance and control of data online in machinery and equipment in real time, nothing is not an easy task. In investment strategy, the choice of appropriate network and the means to establish this communication in the integration of the various equipment distributed in different locations (remote) is an important factor for the success of the data that we want to track. The present work shows the wireless communication technologies-Wireless and Mobile through a search and case study done in the laboratory and UFRGS and SATC College with the creation of a prototype of an interface for data acquisition using the GSM / GPRS cellular network to simulate the transmission and reception of data to the remote monitoring of 02 (two) variables here defined as vibration of the tower and wear of the brake chip in wind power of small. The data studied here show us results that can be useful for any business that plan deploy a system for remote monitoring via the Network Mobile (GSM / GPRS). Although the experiment have used variables of a wind power, are shown other possible applications of remote monitoring using the channel of communication wireless.
64

Finding Social Location Using Bluetooth

Hayat, Umer January 2009 (has links)
From the last few years many location based system have been introduced e.g. facebook, orkut, youtube and my-space etc. These networks are specially developed for personal computers. Some location based systems are also introduced for mobile device e.g. Plazes, MamJam, Slam and Jambo. All these type of networks are using the concept of social location, which provides the platform where people can join or make communities according to their interests. Numbers of users on these networks are increasing day by day due to their popularity. This popularity gives the opportunity for researchers to explore the characteristics of these social networks at large scale. This knowledge will be then used to improve the existing networks or to develop new networks. Already developed systems for mobile devices are using different techniques (e.g. Radio Frequency Identification, GPS, GSM, WAP etc.) to determine the location of any person. In this thesis, I am going to develop a prototype of system that will find the social location of an individual using passive Bluetooth scanning of mobile devices. The main idea behind this prototype is that the data obtained should be flexible to target different social needs and as well as different social location applications. The research will explore some more areas of Bluetooth by extending its dimension in social location system. The expected output from this research will help human being to overcome some of their social problems. Social location obtained from the prototype can be used to fulfill different social needs of human being. Keywords: Social location, Bluetooth, Physical location, GPRS, Mobile applications.
65

Experimental Study of GPRS/WLAN Systems Integration / Experimentell Studie av GPRS/WLAN System Integration

Nyström, Joakim, Seppälä, Mikael January 2003 (has links)
The convergence of future networks relies on the evolution of technology that enables seamless roaming abilities across non-heterogenous networks for mobile clients. This thesis presents an experimental study of a GPRS-WLAN integration scenario where the objective is to analyze various aspects of the issues related to charging, mobility, roaming and security between GPRS and WLAN networks. The mainly discussed integration scenario in this thesis is loosely coupled systems working on RADIUS platforms, which together with MobileIP and IPSec provides the mobile client with a secure and access-technology independent network access platform. In order to accommodate GPRS client authentication for WLAN operators, there is a prominent need for the incorporation of necessary GPRS functionality into present AAA servers. RADIUS has been studied as the initial target for the implementation of a GPRS interface towards SMS-Cs and HLRs.The authentication of a mobile client is performed against a HLR/AuC in a GPRS network, either over SS7 links or through the incorporation of SIGTRAN protocols over SCTP. SIGTRANsolutions has the ability to join WLAN networks in a SS7 resource sharing model where the SS7 authentication signalling traffic is transported over IP networks to a Signalling Gateway acting as the logical interface against SS7 networks. GPRS-WLAN accounting may be solved through direct roaming agreements between mobile operators and in such a case transport CDR’s over FTP between their billing systems. If roaming agreements does not exist, it may be viable to establish relationships between WLANs and brokers as well as mobile operators and brokers. The brokering model provides a scalable model that allows easier exchange of charging and billing information on an infrastructure based on WLAN and GPRS billing systems. Standardised transmission protocols for accounting information such as GTP’/TAP3 may be utilised in order to provide a generic billing exchange format between billing systems and operators. Furthermore, different network architectures may have different requirements in order to accommodate GPRS clients with WLAN access. A few network architectures has been analysed, and the developed GPRS AAA Interface Daemon (GAID) has been put into context in order to present a generic GPRS-WLAN systems integration solution for WLAN operators. The analysed solutions in this thesis give various possibilities for WLAN operators to setup wireless services for bypassing mobile clients. The implementational work provides a RADIUS platform, which can be enhanced with functionality that enables communication over any interface in the future.
66

Link QualityControl (LQC) i GPRS/EGPRS

Seddigh, Sorosh January 2003 (has links)
This master thesis has been done at Enea Epact AB. The purpose of this thesis is to develop and implement a Link Quality Control algorithm for GPRS/EPGRS in the current testing tool. A Link Quality Control (LQC) shall take quality values from mobile stations and base stations and decide a codingsscheme that opimizes the throughput of data. The Advantage with LQC is that it adapts the used coding scheme to the channel quality. If the channel quality is too bad for the used coding scheme, a slower coding scheme with more redundancy should be selected. On the other hand, if the channel quality is too good for the used coding scheme, LQC should recommend a faster coding scheme with less redundancy. The testing tool is now using a static coding schme that doesn’t change during a data session. An LQC is therefore necessary for better simulation of the traffic and to make the tests more real.
67

Bildöverföring via Bluetooth till ett GPRS nätverk / Image Transport to a GPRS Network using Bluetooth

Hellberg, Carl, Fransson, Daniel January 2002 (has links)
På Ericsson AB i Katrineholm finns ett tekniklaboratorium (Techlab), där den senaste tekniken för GPRS-system finns samlad. Till Ericssons tekniklaboratorium skulle en demo-applikation konstrueras. Applikationen ska illustrera hur en mobiltelefon av typen Ericsson T68 kan skicka en bild via Bluetooth till en LAN nod (BlipC11). Den är kopplad till ett GPRS-nätverk och ska i sin tur skicka vidare bilden till en mottagare på andra sidan nätet. Rapporten ger en teoretisk bakgrund om Bluetooth och GPRS. Vidare i rapporten presenteras lösningsförslag och resultatet av examensarbetet. Projektet har varit problemfyllt. De resultat och slutsatser som erhållits är att utrustningen som varit tillgänglig inte klarar av att handskas med bildobjekt. Det betyder att kravspecifikationen ej kunde fullföljas. Alternativa användningsområden för noden har undersökts, som WAP- eller webserver. En webserver samt olika applikationsexempel till noden är resultatet av detta examensarbete. / At Ericsson AB in Katrineholm is a technical lab (Techlab) located, where the latest technique for GPRS-systems is gathered. A demo-application where supposed to be build for Techlab. The demo-application shall demonstrate the capabilities of Bluetooth and GPRS. An Ericsson T68 mobile will wirelessly send an image across a Bluetooth link to a LAN access point (BlipC11). The access point will then transport the image further on to the GPRS-net to a receiver, at the other end of the net. The report gives a theoretical background about Bluetooth andGPRS. In the report, methods and results of the final year project are presented. During the project a several problems occurred. The results and the conclusions show that an image can’t be sent with the equipment that was handed out. This means that the assignment specification could not be fulfilled. Other scenarios with the LAN access point have been investigated. It could be used as a WAP- or webserver for example. A webserver and some application examples for the access point, is the result of this project.
68

"Halfpipe Active Channel"- developing a secure communications protocol / "Halfpipe Active Channel"- utveckling av ett säkert kommunikationsprotokoll

Larsson, Fredrik January 2005 (has links)
With the advent of powerful multimedia capable mobile phones, the market for mobile services is flourishing. Zenterio AB's Halfpipe Active Desktop is a complete distributed mobile service platform a with a powerful server and platform-independent client. The communication between the client and server takes place over a GPRS-capable mobile network. The purpose of this thesis is to develop a secure communications protocol for use between the Halfpipe Active Desktop client and server. This is done by determining requirements, analyzing candidate protocols and then by designing the final protocol. The result, the Halfpipe Active Channel protocol, is an authorized, encrypted, session oriented, message based and light weight protocol designed to minimize computational as well as network overhead. This master's thesis project was defined by and performed at Zenterio AB during the second half of 2004.
69

Utveckling av en radiolänkssimulator / Development of a radio link simulator

Nilsson, Fredrik, Wånggren, Jonas January 2008 (has links)
Den här uppsatsen handlar om utvecklingen av en radiolänkssimulator åt företaget Icomera. Icomera inriktar sig på att sälja och distribuera internetåtkomst på tåg. Företagets affärsidé bygger på att sälja system som använder sig av olika trådlösa länkar som simultant skickar och tar emot data med hjälp av ett egenutvecklat protokoll. Icomera har sålt sitt system till bl.a. Statens järnvägar (SJ), för att möjliggöra internetåtkomst från tågen. Radiolänkssimulatorn används idag i Icomeras laboratorium vid testning och verifiering av tågsystemet, i och med att den ger en mer kontrollerad miljö än ett riktigt tåg. Rapporten redogör för hur trådlösa länkar beter sig i verkligheten och hur deras beteende kan simuleras. Rapporten berör främst de problematiska delarna av implementationen, men också teori i form av bl.a. statistiska modeller. Radiolänkssimulatorn har till största del skrivits i programspråket C# .NET, vilket har lett till flera olägenheter som behandlas i rapporten. De flesta olägenheter har främst med prestandaförluster att göra. / This master thesis deals with the creation of a link simulator to be used by the company Icomera. Today the link simulator is used in Icomera’s laboratory for simulating wireless links. Icomera’s business concept is to sell and distribute internet access on trains and other vehicles. They use different wireless connections for simultaneously transfer data wrapped in their own protocol. Icomera has sold the system to Statens järnvägar (SJ), to enable internet access from trains. The link simulator is used for testing and verification of Icomera’s train system. Hence it can be done in a more controlled environment than onboard a real train. The report describes how wireless links acts in reality and how this behavior can be simulated. The report handles mainly the problematic parts of the implementation but also theory, e.g. statistic models. The link simulator has primarily been written in the programming language C# .NET which has lead to several inconveniences which is discussed in the report. Most of the inconveniences have to do with performance loss.
70

Smartcard based heart-beat service for M2M communication

Erlandsson, Marcus January 1984 (has links)
This study concerns machine-to-machine (M2M) applications that use smartcards. More specifically,The Subscriber Identity Module (SIM) smart card is used for the purpose of monitoring a continuousnetwork connection between a host device and a server. Multicom Security is a security company thatoffers several secure communication connection services (e.g. payment transactions, alarm signals). Themonitoring of these connections is carried out with continuous heart-beat messages sent from thedevice to a server. Today they provide this heart-beat service through logic in their own manufactureddevices, but they have a desire to place the logic on a SIM card in order to be able to move such serviceswith this card and not with a device. Such services can then also be offered on devices not necessarilymanufactured by Multicom Security.The work consisted of investigation of current telecommunication standards, papers regardingsmartcard applications and the current monitoring service, in order to consider possible solutions toimplement a proof of concept of such solution and evaluate it. One aspect of the study was to checkwhether the implemented solution was general and would work in different mobile equipments and alsoto determine the limitations of such smartcard applications.Three solutions were considered for implementation of which one was successfully implemented andtested. The successful heart-beat application was developed using a network subscription enabled JavaCard smart card and using SMS as bearer for the heart-beat messages. By evaluating the solution withbasic tests of functionality, robustness, performance and compatibility the solution was considered to begeneral and compliant with most new mobile equipments. The evaluation was performed in realenvironment with the application running on an actual SIM card with network subscription tested indifferent mobile devices such as cell phones, built-in communication modules and alarm control panels.An alternative solution based on GRPS instead of SMS was also realized but the tests could not becarried out completely due to lack of access to the SIM card implementation by the card provider.

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