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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

A CELLULAR PHONE-CENTRIC MOBILE NETWORK ARCHITECTURE FOR WIRELESS SMALL SATELLITE TELEMETRY SYSTEM

Li, Mingmei, Guo, Qing 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper aims to add the information access capabilities to enable user’s mobile terminals in a wireless small satellite telemetry system. The cellular phone-centric mobile network architecture provides wireless communication link; telemetry information is provided to users in a highly personalized form according to the end-user’s range. We choose a reference system-level model of network architecture and compare its performance with common small satellite telemetry network link; evaluation results derived using a known analytical model. The result of original hypotheses, network architecture’s prototype includes both analytical performance evaluation and simulation techniques, are discussed in detail.
2

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.
3

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.
4

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
5

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.
6

The Effects of Simulated Cellular Phone Conversation on Road-Crossing Safety

Murray, Stephen James January 2006 (has links)
The effects that cellular (cell) phone conversation may have on pedestrian road-crossing performance is unknown. A series of experiments was conducted using a virtual reality road crossing simulator to examine this issue. The participants were primarily university students aged between 18 and 24 years old, although one study compared a group aged 18 to 24 to a group between 50 and 67 years old. Two experimental situations were used: a gap-choice situation, in which the participants had to choose a gap to cross through; and an infrequency situation, where vehicles were present on only 10% of the trials. Participants were impaired by a simulated phone conversation task when compared to no-conversation task, as evidenced by longer reaction times, slower walking speeds, poorer gap choices, and more cautious behaviours. Most importantly, conversation was related to a decrease in the mean margins of safety, and the participants were hit or nearly hit by vehicles more often when talking. The general performance of the older participants did not differ from that of the younger participants, and both groups were impaired to a similar extent by the conversation task. Participants were found to use irrelevant distance information to inform their gap-choice decisions, a strategy associated with a decrease in safety as the distance between the vehicles increased. It was also found that their use of time-to-arrival information was impaired when engaged in the conversation task. Overall, talking on a cell phone while crossing a road may represent an unnecessary increase in risk; therefore, care should be taken if these two acts are being conducted concurrently.
7

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.
8

[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.
9

Decision Making in the Backcountry While Carrying a Cellular Phone

Linford, Quinn S. 01 December 2016 (has links)
The purpose of this study was to gain understanding about the influence of technology, specifically cellular phones, on decision making during potentially risky situations in the backcountry. Previous research in this area is contradictory and some studies indicate technology is influencing people to take more risks while others suggest it is not. Further confounding the relationship is the fact that previous studies have found people may be taking more risk in the presence of technology were based largely on respondent perceptions, not observation data. The current study used a scenario-based decision model to examine the difference in decision making between those who carried a cell phone on a hike and those who did not. A one-way ANCOVA revealed there was no statistical difference (F=2.18, p=.0898) between the two groups. This indicated people did not take more risks because they carried a cell phone into the backcountry. Risk tolerance and experience hiking long mountain hikes similar to the mountain used in the scenario were the only two variables that influenced decision making in this model. Because cell phones do not adversely influence decision making, it is proposed cell phones and other wireless communication devices be added as a recommended piece of gear to the 10 essentials to help reduce the time it takes for search and rescue to arrive on scene when help is needed.
10

The Effects of Simulated Cellular Phone Conversation on Road-Crossing Safety

Murray, Stephen James January 2006 (has links)
The effects that cellular (cell) phone conversation may have on pedestrian road-crossing performance is unknown. A series of experiments was conducted using a virtual reality road crossing simulator to examine this issue. The participants were primarily university students aged between 18 and 24 years old, although one study compared a group aged 18 to 24 to a group between 50 and 67 years old. Two experimental situations were used: a gap-choice situation, in which the participants had to choose a gap to cross through; and an infrequency situation, where vehicles were present on only 10% of the trials. Participants were impaired by a simulated phone conversation task when compared to no-conversation task, as evidenced by longer reaction times, slower walking speeds, poorer gap choices, and more cautious behaviours. Most importantly, conversation was related to a decrease in the mean margins of safety, and the participants were hit or nearly hit by vehicles more often when talking. The general performance of the older participants did not differ from that of the younger participants, and both groups were impaired to a similar extent by the conversation task. Participants were found to use irrelevant distance information to inform their gap-choice decisions, a strategy associated with a decrease in safety as the distance between the vehicles increased. It was also found that their use of time-to-arrival information was impaired when engaged in the conversation task. Overall, talking on a cell phone while crossing a road may represent an unnecessary increase in risk; therefore, care should be taken if these two acts are being conducted concurrently.

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