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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.
1

Acquisition and tracking of weak GPS signals as received by cellular telephones

Grant, Howard Alexander 25 January 2011
This thesis investigates the suitability of global navigation satellite system (GNSS) signals for cellular phone location. The requirement is to determine and report the location of a phone during an emergency call.<p> The thesis analyzes acquisition and tracking techniques suitable for very weak signals as received by a cellular phone indoors. The L1 and L5 signals from GPS satellites and the L1 signal from Galileo satellites are considered. It is shown that long integration times and coherent integration are required for the weakest expected signals. Long coherent integration times require a precise knowledge of the Doppler shift due to the range rate of the satellite. The tolerance to Doppler shift can be increased by using FFTs in the analysis of the data. Non-coherent averaging techniques improve the Doppler tolerance but compared to coherent averaging, the loss of signal to noise ratio is too large for the weakest signals.<p> Coherent averaging of the GPS L1 signal requires data removal that can be accomplished with assistance from the cellular network. The GPS L5 and Galileo L1 signals include a data-less or pilot channel. The GPS L5 pilot channel includes a 20 bit Neuman Hoffman code with a bit period of 1 ms. This code has to be acquired or removed before coherent averaging. Similarly the Galileo pilot channel includes a 25 bit short code.<p> Once code acquisition has been accomplished, it is necessary to track the signals from at least four satellites for long enough to compute a position estimate. A discussion of tracking techniques is included to show the signal to noise ratio limitations for adequate tracking accuracy.<p> The results show that GNSS signals are suitable for cellular phone location in a large number of situations. Increased receiver sensitivity would permit location in additional situations. In rural situations GNSS may be the only available option.
2

Acquisition and tracking of weak GPS signals as received by cellular telephones

Grant, Howard Alexander 25 January 2011 (has links)
This thesis investigates the suitability of global navigation satellite system (GNSS) signals for cellular phone location. The requirement is to determine and report the location of a phone during an emergency call.<p> The thesis analyzes acquisition and tracking techniques suitable for very weak signals as received by a cellular phone indoors. The L1 and L5 signals from GPS satellites and the L1 signal from Galileo satellites are considered. It is shown that long integration times and coherent integration are required for the weakest expected signals. Long coherent integration times require a precise knowledge of the Doppler shift due to the range rate of the satellite. The tolerance to Doppler shift can be increased by using FFTs in the analysis of the data. Non-coherent averaging techniques improve the Doppler tolerance but compared to coherent averaging, the loss of signal to noise ratio is too large for the weakest signals.<p> Coherent averaging of the GPS L1 signal requires data removal that can be accomplished with assistance from the cellular network. The GPS L5 and Galileo L1 signals include a data-less or pilot channel. The GPS L5 pilot channel includes a 20 bit Neuman Hoffman code with a bit period of 1 ms. This code has to be acquired or removed before coherent averaging. Similarly the Galileo pilot channel includes a 25 bit short code.<p> Once code acquisition has been accomplished, it is necessary to track the signals from at least four satellites for long enough to compute a position estimate. A discussion of tracking techniques is included to show the signal to noise ratio limitations for adequate tracking accuracy.<p> The results show that GNSS signals are suitable for cellular phone location in a large number of situations. Increased receiver sensitivity would permit location in additional situations. In rural situations GNSS may be the only available option.
3

Versos-livres = a estética do cotidiano no documentário feito com celular / Free-verses : the aesthetic of quotidian in documentary done with cellular-phone

Freitas, Kênia Cardoso Vilaça de 17 August 2018 (has links)
Orientador: Francisco Elinaldo Teixeira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Artes / Made available in DSpace on 2018-08-17T01:00:00Z (GMT). No. of bitstreams: 1 Freitas_KeniaCardosoVilacade_M.pdf: 6009777 bytes, checksum: d242ab3c2946d0676852f63c25904e5e (MD5) Previous issue date: 2010 / Resumo: Essa dissertação propôs-se a fazer uma análise do cinema contemporâneo a partir do universo dos filmes feitos com telefone celular, especificamente dos documentários. Para começar, procuramos entender em que contexto da história do cinema esses filmes se situam. Em seguida, mergulhamos nas características mais específicas do dispositivo desses filmes (conectividade, portabilidade e mobilidade), tendo como objeto de análise os filmes participantes do festival Pocket Films. Por fim, traçamos a relação dos filmes feitos com celular com a construção de processos de subjetividade no cinema / Abstract: This paper intends to do an analysis of contemporary cinema throughout the universe of the movies made using cellular phone cameras, specifically of the documentary. At first, we seek to understand the context at the history of cinema in which these movies take place. In the next moment, we dive into the characteristics which are specific to the device of these movies (connectivity, portability and mobility, having as object of analysis the movies that participated in the Pocket Films Festival. At last, we trace the relation between the movies made using cellular camera and the construction of the processes of subjectivity in cinema / Mestrado / Multimeios / Mestre em Multimeios
4

M-hälsa i behandlingen av ungdomar med självskadebeteende

Edlund, Anette, Holmström, Frida January 2014 (has links)
Abstract Background: In Sweden self-harm behaviors among young people have been a difficult area to handle in psychiatric care. From the government's efforts have been made to synchronize the knowledge and experience from the local level aiming to prevent, reduce and faster identify self-harm among young people. M-Health refers to technology such as smartphones, notebooks and mobile phones provide.  These mobile devices have come to revolutionize aspects of health care perhaps mostly among young people, live their digital lives by these electronic media. Aim: To illuminate the use of m-Health in the treatment of mental illness and to present a draft of a mobile application that helps professionals in work with young people active in a mild to moderate self-injury. Method: A literature review based on an analysis of twelve scientific articles with qualitative and quantitative approach. We searched in November 2013-January 2014 Ebsco and PubMed databases.  Results: The literature review is presented as gains and losses in use of m-Health in the treatment of mental illness. The focus has been on what is possible to achieve with a mobile application in this area of concern. It appeared that young people show positive attitudes to using an application in monitoring of psychiatric symptoms and gained more control mental health. The professionals sees advantage in terms of more truthful symptom monitoring in real time in comparison with retrospective self-monitoring, expedited handling processes and better treatment outcomes. Conclusion: We interpret the results of the studies about m-Health as an opportunity for nurses to meet young people, active in a mild to moderate self-harm. An m- Health intervention based on an application for young people could make it easier for nurses to improve their communication and treatment outcomes. Care initiatives and relevant actions can then be tailored to young people's cultural values, beliefs and lifestyle.
5

Linearity and monotonicity of a 10-bit, 125 MHz, segmented current steering digital to analog converter

Bittle, Charles C. 05 1900 (has links)
The purpose of this research is to determine the linearity and monotonicity of the THS5651IDW digital to analog converter (DAC), a prototype of the future Texas Instruments TLV5651, 10-bit, 125 MHz communication DAC. Testing was conducted at the Texas Instruments facility on Forest Lane, Dallas, Texas. Texas Instruments provided test equipment, software and laboratory space to obtain test data. Analysis of the data found the DAC to be monotonic since the magnitude of the differential nonlinearity (DNL) was less than ± 1 least significant bit (LSB) and the integral nonlinearity (INL) was less than ± 0.5 LSB. The study also showed that the DAC has primarily negative DNL although the DNL is well within the desired specification.
6

[en] EVOLUTION OF MOBILE PHONES TECHNOLOGY AND THE IMPACT ON THE WASTE OF ELECTRICAL AND ELECTRONIC EQUIPMENT / [pt] EVOLUÇÃO DA TECNOLOGIA MÓVEL CELULAR E O IMPACTO NOS RESÍDUOS DE ELETROELETRÔNICOS

FABRICIO ROBERTO SENA 06 November 2013 (has links)
[pt] Os produtos da indústria de eletroeletrônicos possuem alta empregabilidade no dia a dia. No entanto, por terem um ciclo de vida curto impactam na demanda por recursos naturais não renováveis. Dentro do universo de equipamentos eletroeletrônicos, os telefones celulares estão entre os mais complexos e os que empregam maior quantidade de elementos químicos diferentes. Apesar de pequenos, são vendidos aos milhares, em parte devido a sua curta vida útil. Esses fatores aliados indicam a existência de riscos à saúde e ao meio ambiente, o que faz repensar como destinar corretamente esses aparelhos no pós-consumo. A proposta do trabalho é fazer uma análise de como os telefones celulares impactam no volume e na complexidade dos Resíduos de Equipamentos Eletroeletrônicos, explicar a razão desse bem essencial ter uma vida útil tão curta e expor os motivos que tornam a sua reciclagem absolutamente necessária para continuar o seu desenvolvimento tecnológico, atender a demanda dos consumidores e reduzir o impacto ambiental da produção ao descarte. / [en] In the last century, through new production processes, the industry has increased the variety and availability of products offered to the population, providing better quality of life. This has happened because the inception of series production has offered a greater supply of consumer goods, including the Electrical and Electronic Equipment (EEE). The evolution of electronics technology has provided, and will continue to provide a better quality of life than the one we used to have. However, the technology of these products is continuously evolving, and this brings advantages and disadvantages.
7

Mobile phone use and risk of intracranial tumors /

Lönn, Stefan, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 4 uppsatser.
8

Voice over IP for Sony Ericsson Cellular Phones / Voice over IP for Sony Ericsson Cellular Phones

Theander, Petter, Hultgren, Thomas January 2005 (has links)
This report presents an investigation of the possibilities to implement voice over IP (VoIP) in Sony Ericsson cellular phones. The results from this investigation show that it is partially possible to implement such a solution. The best option for doing so is to make use of the support for the Session Initiation Protocol and the Real-time Transport Protocol offered by the architecture. Another goal is to evaluate if Bluetooth is able to handle the requirements needed for the solution. The whole concept is proven by implementing a prototype. Measurements on this prototype show that Bluetooth will be able to handle the requirements of most IP-based voice communication, i.e., in respect to latency and bandwidth.
9

Perspektivní služby v oblasti mobilních komunikací / Promising services in mobile communications

Plavec, Tomáš January 2009 (has links)
The aim of this thesis is to propose a new mobile service. At the beginning of this work are listed technologies, which are used in mobile communications. Furthermore, it defines the concept of mobile service, indicating a few examples. The practical part describes a custom design services and its variants. The new service is finally described as a possible new type of business.
10

[pt] CARACTERIZAÇÃO DE PLACAS DE CIRCUITO IMPRESSO DE APARELHOS DE TELEFONE CELULAR VISANDO RECUPERAÇÃO DE METAIS VALIOSOS / [en] CHARACTERIZATION OF PRINTED CIRCUIT BOARD OF MOBILE PHONES AIMING TO RECOVER VALUABLE METALS

03 November 2021 (has links)
[pt] Atualmente um dos setores industriais que mais se desenvolve é a indústria eletroeletrônica. À medida que tecnologias evoluem, barateando os produtos, o consumo de eletroeletrônicos aumenta. O tempo de vida útil de tais produtos é relativamente curto e, em pouco tempo, esse material torna-se resíduo, conhecido como sucata eletrônica. Um tipo de sucata eletrônica comum é o telefone celular. Esta sucata representa uma matéria-prima interessante, pois, contém grande quantidade de metais base, quantidade considerável de metais valiosos e contendo também elementos perigosos. Neste trabalho, as sucatas passaram por várias etapas de processamento mecânico: inicialmente os aparelhos foram separados em lotes (menor 2001; maior 2002) e desmontados manualmente. As placas de circuito impresso foram moídas abaixo de 1 mm, Em seguida, as separações por densidade e magnética foram realizadas. As frações obtidas ao longo do processamento mecânico foram caraterizadas por análises químicas. Realizouse um estudo em caráter preliminar para recuperar prata utilizando processamento hidrometalúrgico. O material concentrado mecanicamente foi lixiviado com ácido nítrico. Em seguida a prata foi recuperada da solução lixiviada por cementação. Com o processamento mecânico foi possível obter frações metálicas de até 80 por cento em peso. A cementação da prata pelo cobre mostrou-se viável, possibilitando obter prata metálica em forma de precipitado e um lixiviado concentrado de cobre. Um ensaio de lixiviação foi realizado com a finalidade de caracterizar o resíduo quanto à sua periculosidade, de modo que, as sucatas de telefone celular devem ser consideradas resíduo perigoso, pois, a concentração de chumbo foi superior ao limite estabelecido pelas normas brasileiras. / [en] Nowadays the electronics industry is the leading sector in developing new technologies. These new technologies lead to cheaper products increasing the consumption. The lifetime of such products is relatively short and soon it becomes waste, known as electronic waste. Cell phone is a common electronic waste. This waste represents an interesting raw material, because it contains large amount of base metals, considerable amount of valuable metals and also those dangerous. In this work, the electronic waste was submitted to mechanical processing: initially the devices were separated into two categories (less 2001,more 2002) and disassembled manually. The printed circuit boards were milled below 1 mm and then submitted to density and magnetic separation processes. The fractions obtained during the mechanical processing were characterized by chemical analysis. Using the mechanical processing was possible to obtain metal fractions of 80 wt per cent. A preliminary study to recover silver using hydrometallurgical processes was carried out. The concentrated material mechanically obtained was leached with nitric acid. Then the silver was recovered from the leached solution by cementation process. The silver cementation with copper was feasible; the precipitate was rich in silver and leachate in copper. A leaching test was carried out to determine if a waste needs to be managed as a hazardous; so that, cell phone waste must be considered hazardous residue because the lead concentration was above the limit established by Brazilian Standards.

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