Dissertations / Theses on the topic 'Cellular telephones'
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Ho, Ming-Ju. "System deployment and capacity enhancing techniques for mobile radio." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/14816.
Kchao, Camroeum. "Direct sequence spread spectrum cellular radio." Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/13719.
Landron, Orlando. "Microwave multipath resolution in microcellular channels." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-03032009-040639/.
Van, Wyk Daniel Jacobus. "Four-dimensional Q2PSK modulation and coding for mobile digital communication." Pretoria : [s.n.], 2000. http://upetd.up.ac.za/thesis/available/etd-10272005-122450.
Caffery, James Joseph Jr. "Wireless location in CDMA cellular radio systems." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/15504.
Wang, Li-Chun. "Channel modeling and architecture for cellular-based personal communications." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/13716.
Tannenbaum, Robert (Robert Peter) Carleton University Dissertation Management Studies. "Cellular telephones; a comparative analysis of their adoption and impacts." Ottawa, 1991.
Berriman, Paul. "The marketing of cellular mobile radio telephones in Hong Kong." Thesis, [Hong Kong : University of Hong Kong], 1985. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12316933.
Parameswaran, Subramanian T. "Software for site specific propagation prediction." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06232009-063433/.
Wu, Jianjun. "Adaptive equalisation techniques for future mobile communications." Thesis, King's College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338815.
Joung, Jinsoup. "Cochannel interference canceling receivers for TDMA systems." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/21806.
Wu, Sun John. "Mobile phone handset strategies of market leaders in Hong Kong /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20604555.
Phongphanphanee, Chai. "Multilayer mobile communication systems." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324001.
Sivanesan, Kathiravetpillai. "A study of performance for M-ary DS/CDMA cellular mobile radio systems." Click to view the E-thesis via HKUTO, 1999. http://sunzi.lib.hku.hk/hkuto/record/B42575333.
Ghaziasgar, Mehrdad. "The use of mobile phones as service-delivery devices in sign language machine translation system." Thesis, University of the Western Cape, 2010. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_7216_1299134611.
This thesis investigates the use of mobile phones as service-delivery devices in a sign language machine translation system. Four sign language visualization methods were evaluated on mobile phones. Three of the methods were synthetic sign language visualization methods. Three factors were considered: the intelligibility of sign language, as rendered by the method
the power consumption
and the bandwidth usage associated with each method. The average intelligibility rate was 65%, with some methods achieving intelligibility rates of up to 92%. The average le size was 162 KB and, on average, the power consumption increased to 180% of the idle state, across all methods. This research forms part of the Integration of Signed and Verbal Communication: South African Sign Language Recognition and Animation (SASL) project at the University of the Western Cape and serves as an integration platform for the group's research. In order to perform this research a machine translation system that uses mobile phones as service-delivery devices was developed as well as a 3D Avatar for mobile phones. It was concluded that mobile phones are suitable service-delivery platforms for sign language machine translation systems.
Fung, Victor. "Bit error simulation of FSK, BPSK, and pi/4 DQPSK in flat and frequency-selective fading mobile radio channels using two-ray and measurement- based impulse response models." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-08142009-040410/.
Alhinai, Yousuf Salim. "The adoption of advanced mobile commerce services by individuals : investigating the impact of the interaction between the consumer and the mobile service provider /." Connect to thesis, 2009. http://repository.unimelb.edu.au/10187/6748.
Ecker, Katelyn D. "Mobile phones as a social medium for the deaf : a uses and gratifications study /." Online version of thesis, 2008. http://hdl.handle.net/1850/7098.
Striglis, Stavros. "A multistage RAKE receiver for CDMA systems." Thesis, Virginia Tech, 1994. http://hdl.handle.net/10919/42211.
Master of Science
Botha, Adele. "The use of mobile phones to mediate a design experiment in a secondary school." Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-02082007-002731/.
Hamblin, Denise Lee. "The effect of mobile phone emitted electromagnetic fields on human brain activity and performance." Australasian Digital Thesis Program, 2006. http://adt.lib.swin.edu.au/public/adt-VSWT20061110.100936.
Thesis for Doctor of Philosophy, Brain Sciences Institute, Faculty of Life and Social Sciences, Swinburne University of Technology - 2002. Typescript. Includes bibliographical references (p. 137-160).
Gong, Jun. "Improved text entry for mobile devices alternate keypad designs and novel predictive disambiguation methods : a dissertation /." View dissertation online, 2007. http://hdl.handle.net/2047/d10016090.
Mooney, Aaron Michael. "Usability Evaluation of Notebook Computers and Cellular Telephones Among Users with Visual and Upper Extremity Disabilities." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/33962.
Master of Science
Tran, Thuy Thomas. "Propagation prediction for PCS design in urban microwave channels." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-03042009-040358/.
Bais, Viraj Kumar. "Simulation of multistage detector for spread-spectrum applications." Master's thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-12232009-020220/.
Pendyala, Chandra Mohan. "On the optimal location of transmitters for micro-cellular radio communication system design." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-07112009-040406/.
Brown, Rowena. "Mobile phone communication in romantic relationships : the role of individual differences and relational uncertainty on text message communication outcomes /." [St. Lucia, Qld.], 2006. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19746.pdf.
Schwenke, Freddie. "Access channels for mobile banking applications : a comparative study based on characteristics." Thesis, Cape Peninsula University of Technology, 2009. http://hdl.handle.net/20.500.11838/1383.
The objective of this research project was to provide an answer to the question: 'Which access channel is the most appropriate for mobile applications?' This question is posed by providers of mobile banking services and providers of mobile banking applications alike.
Li, Yingjie. "Bit error rate simulation of a CDMA system for personal communications." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-07282008-135717/.
Lichtenstein, Joseph. "Low computational complexity bit error rate simulation for personal communications systems in multipath and fading environments." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06102009-063138/.
Broege, Stephanie, and n/a. "Mobile New Zealand : a multi-method comparative study of cell phone use." University of Otago. Department of Media, Film and Communication Studies, 2008. http://adt.otago.ac.nz./public/adt-NZDU20080819.150246.
Kong, Wei Chao. ""It is mine, it is me!" : the use of mobile phones of young people in Macau and Guangzhou." Thesis, University of Macau, 2007. http://umaclib3.umac.mo/record=b1874201.
Goetz, Marieta. "Mobile business models in African rural communities." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/2581.
Mobile telephone subscription in developing countries has increased by more than 500 percent since 2005, with Africa experiencing the highest growth rate globally. Amongst Africa’s 306.5 million subscribers, recorded in 2008, an unexpectedly high adoption rate of the technology by poor, often illiterate rural communities is observed. Mobile telephony generally provides African rural users access to electronic communication for the first time. Providing access to communication, information and knowledge, mobile phones present a platform for economic and social interaction in rural Africa. The extent of the resulting positive socio-economic impact on the developing world has lead to mobile telephony increasingly being viewed as a potential development tool for the socio-economic upliftment of the rural poor. This thesis is inspired by the potential for value creation to end users of mobile telephony, leading to the proposition that the rapid expansion of mobile telephony in rural Africa can contribute significantly to the sustainability of these communities’ rural livelihoods. For this proposition to be valid, mobile telephony has to provide value beyond being communication tool. It has to provide value in income generating activities by increasing opportunities for access to financial and social capital with mobile business models appropriate to the rural African context. To assess the appropriateness of mobile value offerings, the rural African context was analyzed using the Sustainable Livelihoods Framework. Through multi-level analysis, the challenges and issues that influence the lives of the rural poor were explored and the dominant livelihood strategies in terms of income generating activities were identified. Apart from agricultural income streams, waged labor, migration and micro-entrepreneurial activities provide non-agricultural income streams. Creating an appropriate mobile business ecosystem for rural Africa requires the collaboration of a complex network of actors within a value constellation to co-produce value for the end users. Three conditional factors were identified for mobile telephony and emerging mobile business models to contribute successfully to sustainable livelihoods: adaptation of the technology by providers, user appropriation to make the technology their own and the assimilation of it into their livelihood strategies. These factors were researched for validation through the study of existing literature and reported case studies. It was found that these three conditional factors were unequivocally met. Firstly, the mobile telecommunication industry active in Africa is seen to successfully adapt and innovate solutions that are relevant to African rural communities’ vulnerabilities and livelihood strategies. Secondly, African mobile phone users have successfully adopted and appropriated mobile telephony to create value for themselves in their livelihood strategies, often independent of external interventions. They are claiming ownership of the technology and not merely using it as a communication tool. Thirdly, by assimilating mobile telephony into their livelihood strategies, value-creation within their income generating activities have been made possible. This value creation is impacting users’ social and financial capital positively. This thesis concludes that mobile telephony and emerging mobile business models are contributing to increasing African rural dwellers’ income generating potential, reducing their vulnerability to shocks, and providing them with a voice; thereby contributing to sustainable rural livelihoods.
Duma, Lindokuhle Sifso. "An authoring tool for generalised scenario creation for SignSupport." University of the Western Cape, 2016. http://hdl.handle.net/11394/6224.
This thesis describes the development cycles of an authoring tool that generalises scenario creation for SignSupport. SignSupport is a mobile communication tool for Deaf people that currently runs on an Android smartphone. The authoring tool is computer-based software that helps a domain expert, with little or no programming skills, design and populate a limited domain conversation scenario between a Deaf person and a hearing person, e.g., when a Deaf patient collects medication at a hospital pharmacy or when a Deaf learner is taking a computer literacy course. SignSupport provides instructions to the Deaf person in signed language videos on a mobile device. The authoring tool enables the creation and population of such scenarios on a computer for subsequent 'playback' on a mobile device. The output of this authoring tool is an XML script, alongside a repository of media les that can be used to render the SignSupport mobile app on any platform. Our concern was to iteratively develop the user interface for the authoring tool, focusing on the domain experts who create the overall flow and content for a given scenario. We had four development iterations, where the rst three were evaluated for usability; for both pharmacy and ICDL course scenarios with purposive sampling. The fourth iteration focused on using the authoring tool to design an ICDL practise mobile app, recording the necessary SASL videos and using an XML parser to render the designs XML script into an Android app. The research conducted herein leveraged multiple approaches to content authoring and generalisation; and further that software generalisation can improve accessibility and a ordability for the ultimate end users. The thesis concludes with a summary of recommendations and lessons learnt.
Liu, Danyi. "Mobile phone based remote monitoring system." Click here to access this resource online, 2008. http://hdl.handle.net/10292/526.
Freudenberg, Kristy. "Investigating the impact of SMS speak on the written work of English first language and English second language high school learners." Thesis, Stellenbosch : Stellenbosch University, 2009. http://hdl.handle.net/10019.1/2052.
This study examined the impact of SMS speak on the written school work of English first language (L1) and English second language (L2) high school learners. The general aims of the study were to establish how widespread the use of SMS language is among high school learners, and to assess whether there is any evidence of the use of features of SMS speak in the English written work of these learners. Eighty-eight learners from an English-Afrikaans dual medium school in a middle class neighborhood in the Western Cape participated in this study. The participants included 43 grade 8s and 45 grade 11s, of which 51 were English L1 speakers and 37 English L2 speakers. The participants completed questionnaires from which the frequency and volume of their SMS use was determined, as well as the features of SMS speak they reportedly use while SMSing. In addition, samples of the learners’ English written work were examined for specific features of SMS speak. These features included (deliberate) spelling errors, lack of punctuation, over-punctuation, the omission of function words, the use of abbreviation or acronyms, and the use of emoticons and rebus writing. The results of this study indicate that high school learners are avid users of SMS and/or MXit. All participants reported using features of SMS speak in their SMSes, and many reported using SMS speak in their written school work. Despite this, the samples of written work did not contain a great number of incidences of SMS speak features. It seems that the general lack of SMS speak in the written work of these learners is a result of being able to assess when it is and is not appropriate to use a certain variety of language: These learners are proficient in SMS speak and use it when chatting to friends on MXit, but they can produce written work that adheres to the formally approved standards of written high school English. That said, a number of SMS speak features were indeed present in their formal written work, which indicates that SMS speak had some impact on the written work of these learners, which could in turn be attributed to the high frequency of their SMS usage. However, not all of the non-standard features of their written English could necessarily be attributed to the influence of SMS speak; specifically some of the spelling and punctuation errors could be unrelated to SMS speak, as they have been noted in the written English of high school learners from before the advent of cellphones. The learners in this study were from a school that has a strict language policy, one which does not tolerate the use of SMS speak in written work. Seven of the teachers completed a questionnaire compiled for all teachers at the school in question. Responses to this questionnaire, especially those of the language teachers, indicated that teachers either deduct marks for features of SMS speak in written language or refuse to mark written work that does not conform to the formally approved standards that the school has set in place. It is possible that the actions of the teachers and the language policy of the school play a significant role in the lack of SMS speak features in the written language use of the learners.
Cuba-Alvarado, Ciara-Paola. "Uso de los celulares con internet y rendimiento académico de estudiantes universitarios." Bachelor's thesis, Universidad de Lima, 2016. http://repositorio.ulima.edu.pe/handle/ulima/4761.
Tesis
Oelofse, Christina Hermiena. "The learner profile of a teenage cell phone user." Diss., Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-07102009-160407.
Vaca-Morales, Dario-Pablo. "Instalación del servicio de telefonía móvil para la conectividad y desarrollo social en las localidades de Apurímac, Ayacucho y Huancavelica." Bachelor's thesis, Universidad de Lima, 2016. http://repositorio.ulima.edu.pe/handle/ulima/3201.
Trabajo de investigación
Lu, Yun Ran. "Position mobile phone market." Thesis, University of Macau, 2000. http://umaclib3.umac.mo/record=b1636664.
Van, Heerden Johan H. "Detecting fraud in cellular telephone networks." Thesis, Stellenbosch : Stellenbosch University, 2005. http://hdl.handle.net/10019.1/50314.
ENGLISH ABSTRACT: Cellular network operators globally loose between 3% and 5% of their annual revenue to telecommunications fraud. Hence it is of great importance that fraud management systems are implemented to detect, alarm, and shut down fraud within minutes, minimising revenue loss. Modern proprietary fraud management systems employ (i) classification methods, most often artificial neural networks learning from classified call data records to classify new call data records as fraudulent or legitimate, (ii) statistical methods building subscriber behaviour profiles based on the subscriber’s usage in the cellular network and detecting sudden changes in behaviour, and (iii) rules and threshold values defined by fraud analysts, utilising their knowledge of valid fraud cases and the false alarm rate as guidance. The purpose of this thesis is to establish a context for and evaluate the performance of well-known data mining techniques that may be incorporated in the fraud detection process. Firstly, a theoretical background of various well-known data mining techniques is provided and a number of seminal articles on fraud detection, which influenced this thesis, are summarised. The cellular telecommunications industry is introduced, including a brief discussion of the types of fraud experienced by South African cellular network operators. Secondly, the data collection process and the characteristics of the collected data are discussed. Different data mining techniques are applied to the collected data, demonstrating how user behaviour profiles may be built and how fraud may be predicted. An appraisal of the performances and appropriateness of the different data mining techniques is given in the context of the fraud detection process. Finally, an indication of further work is provided in the conclusion to this thesis, in the form of a number of recommendations for possible adaptations of the fraud detection methods, and improvements thereof. A combination of data mining techniques that may be used to build a comprehensive fraud detection model is also suggested.
AFRIKAANSE OPSOMMING: Sellulêre netwerk operateurs verloor wêreldwyd tussen 3% en 5% van hul jaarlikse inkomste as gevolg van telekommunikasie bedrog. Dit is dus van die uiterse belang dat bedrog bestuurstelsels geïmplimenteer word om bedrog op te spoor, alarms te genereer, en bedrog binne minute te staak om verlies aan inkomste tot ’n minimum te beperk. Moderne gepatenteerde bedrog bestuurstelsels maak gebruik van (i) klassifikasie metodes, mees dikwels kunsmatige neurale netwerke wat leer vanaf geklassifiseerde oproep rekords en gebruik word om nuwe oproep rekords as bedrog-draend of nie bedrog-draend te klassifiseer, (ii) statistiese metodes wat gedragsprofiele van ’n intekenaar bou, gebaseer op die intekenaar se gedrag in die sellulêre netwerk, en skielike verandering in gedrag opspoor, en (iii) reëls en drempelwaardes wat deur bedrog analiste daar gestel word, deur gebruik te maak van hulle ondervinding met geldige gevalle van bedrog en die koers waarteen vals alarms gegenereer word. Die doel van hierdie tesis is om ’n konteks te bepaal vir en die werksverrigting te evalueer van bekende data ontginningstegnieke wat in bedrog opsporingstelsels gebruik kan word. Eerstens word ’n teoretiese agtergrond vir ’n aantal bekende data ontginningstegnieke voorsien en ’n aantal gedagteryke artikels wat oor bedrog opsporing handel en wat hierdie tesis beïnvloed het, opgesom. Die sellulêre telekommunikasie industrie word bekend gestel, insluitend ’n kort bespreking oor die tipes bedrog wat deur Suid-Afrikaanse sellulˆere telekommunikasie netwerk operateurs ondervind word. Tweedens word die data versamelingsproses en die eienskappe van die versamelde data bespreek. Verskillende data ontginningstegnieke word vervolgens toegepas op die versamelde data om te demonstreer hoe gedragsprofiele van gebruikers gebou kan word en hoe bedrog voorspel kan word. Die werksverrigting en gepastheid van die verskillende data ontginningstegnieke word bespreek in die konteks van die bedrog opsporingsproses. Laastens word ’n aanduiding van verdere werk in die gevolgtrekking tot hierdie tesis verskaf, en wel in die vorm van ’n aantal aanbevelings oor moontlike aanpassings en verbeterings van die bedrog opsporingsmetodes wat beskou en toegepas is. ’n Omvattende bedrog opsporingsmodel wat gebruik maak van ’n kombinasie van data ontginningstegnieke word ook voorgestel.
Blood, Alan Physics Faculty of Science UNSW. "Biological effects of GSM mobile phone microwave radiation: an investigation of gene expression." Awarded by:University of New South Wales. School of Physics, 2005. http://handle.unsw.edu.au/1959.4/22071.
Soroa-Koury, Sandra. "Consumers' responses to mobile advertising a normative social behavior perspective /." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
Hancox, Graham. "Factors affecting drivers willingness to engage with a mobile phone while driving." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/14754.
Passetti, Renata Regina 1981. "O efeito do telefone celular no sinal da fala : uma análise fonético-acústica com implicações para a verificação de locutor em português brasileiro." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/271133.
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Estudos da Linguagem
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Resumo: Esta dissertação avalia os efeitos causados ao sinal da fala pela transmissão telefônica de linhas móveis e, com isso, busca determinar o grau de modificação fonético-acústica intralocutor causado pelo filtro de banda do canal telefônico à voz habitual e os efeitos que a transmissão telefônica exerce sobre as vogais orais do português brasileiro, pelo estudo de parâmetros acústicos que são afetados por esse tipo de transmissão. As análises investigaram quais características acústicas eram modificadas e quais permaneciam inalteradas na fala de indivíduos diante da utilização de telefones celulares quando comparadas a gravações diretas. O corpus constitui-se de gravações de 10 locutores do sexo masculino, realizadas de forma simultânea nas condições via celular e direta, pelo posicionamento de um microfone em frente aos sujeitos enquanto falavam ao celular. As vogais orais do português brasileiro foram transcritas e segmentadas e, posteriormente, foi utilizado o script ForensicDataTrecking para extração automática das seguintes classes de parâmetros: frequência dos três primeiros formantes (F1, F2 e F3), frequência fundamental (F0), ênfase espectral, frequência de base da fundamental (baseline) e duração interpicos de F0 presentes no discurso. Foram conduzidas análises acústicas com o objetivo investigar os efeitos da transmissão telefônica sobre as vogais orais do português brasileiro, sobre os locutores e no espaço vocálico dos locutores. As análises foram validadas estatisticamente. Para a análise do efeito da transmissão telefônica sobre as vogais orais do português brasileiro, os resultados revelam alterações nas frequências do primeiro e o terceiro formante de, aproximadamente, 14%, na condição telefônica. Em relação às frequências do segundo formante, os resultados da análise de dispersão mostraram que a transmissão telefônica agiu de forma a aumentar artificialmente as frequências de vogais com baixos valores de F2 e a diminuir as frequências de vogais com altos valores de F2. Dos parâmetros acústicos investigados na análise dos efeitos da transmissão telefônica sobre os locutores, apenas a baseline e a duração interpicos de F0 não apresentaram diferenças estatisticamente significativas entre as duas condições de gravação, indicando robustez aos efeitos da transmissão telefônica e podendo ser considerados como parâmetros eficazes na análise forense. Esta análise revelou, também, que a transmissão telefônica agia de maneira distinta nos sujeitos, o que permitiu que fossem agrupados a depender do parâmetro investigado. A análise do efeito telefônico no espaço vocálico dos sujeitos complementou os resultados das análises anteriores. De modo geral, observou-se um abaixamento global do espaço vocálico na gravação telefônica, influenciado pelo aumento nas frequências de F1. A diminuição dos valores de F2 para as vogais anteriores e o aumento nos valores deste formante para vogais posteriores comprimiu o espaço vocálico da maioria dos sujeitos. As modificações nas disposições das vogais têm implicações perceptuais, uma vez que o abaixamento e redução do espaço vocálico fizeram com que as vogais se situassem proximamente a regiões centrais, podendo soar como mais abertas no telefone celular
Abstract: This dissertation evaluates the effects to speech signal due to telephone transmission of mobile phones and seeks to determine the degree of intra-speaker acoustic-phonetic modification caused by the mobile phone band-pass filter to the speech signal and the telephone transmission effects over the Brazilian Portuguese oral vowels by the study of the acoustic parameters affected by this kind of transmission. The analysis investigated which are the acoustic cues which are modified and which cues remain undifferentiated in the speaker's speech by the use of a mobile phone in comparison to direct recordings. The corpus used consists of simultaneous recordings of 10 male speakers in two conditions: via mobile phone and face-to-face, by placing a microphone directly in front of the subjects. The Brazilian Portuguese oral vowels were segmented and transcribed and the ForensicDataEvaluator script was used to automatically extract the following acoustic parameters: three first formants frequencies (F1, F2 and F3), median of fundamental frequency (F0), spectral emphasis, fundamental frequency baseline and F0 inter-peaks duration. The acoustic analyses aimed at investigating the telephone transmission effects over the Brazilian Portuguese oral vowels, over the speakers and at the speakers¿ vowel space. The analyses were supported statistically. The analysis of the telephone transmission effect over the Brazilian Portuguese oral vowels showed variations of 14% in the frequencies of the first and the third formants. The analysis of the scatter plot of F2 values showed that the mobile phone band-pass filtering has an effect of shifting upwards vowels with low values of F2 and shifting downwards vowels with high values of F2. For the analysis of the telephone transmission effects over the speaker only the acoustic parameters "fundamental frequency baseline" and "F0 inter-peaks duration" did not show any difference statistically significant between the two recording conditions, demonstrating robustness to the telephone transmission effects, which make them able to be considered as powerful parameters for forensic analysis. This analysis also revealed that the telephone transmission affects the speakers in different ways, which set them into different groups of speakers depending on the parameter analyzed. The analysis of the telephone effect in the speakers¿ vowel space shed some light on the previous analyses. In general, the increase of the F1 values in the mobile phone situation caused a global downward displacement of the vowel space. The decrease of the F2 values for the front vowels and the increase of the values of this formant for back vowels reduced the area of the vowel space for the most of the subjects. The vowels rearrangement at the vowel space in the telephone situation has some perceptual implications, since the lowering and reduction of the vowel space made the vowels be placed at its center, which could result in hearing these vowels as more open over the mobile phone
Mestrado
Linguistica
Mestra em Linguística
Geary, Wendy. ""No matter where you go, there you are" but how do we find you? location determination technologies for cellular enhanced 9-1-1 service /." Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=982.
Title from document title page. Document formatted into pages; contains vii, 85 p. : ill. (some col.) Vita. Includes abstract. Includes bibliographical references (p. 74-81).
Lin, Hai Yun. "The magic wand : mobile phone use and Fujian entrepreneurs in China." Thesis, University of Macau, 2008. http://umaclib3.umac.mo/record=b1874128.
Chio, Nga I. "The uses and perceptions of mobile phone in Macau." Thesis, University of Macau, 2009. http://umaclib3.umac.mo/record=b2162007.
Ouersoontornwatana, Ajana. "Nokia's marketing stategies of mobile phones in Thailand and Hong Kong." CSUSB ScholarWorks, 2002. https://scholarworks.lib.csusb.edu/etd-project/2208.
Li, Hong Ye. "Challenging the mainstream : youth identity and the popularity of Shanzhai mobile phones in China." Thesis, University of Macau, 2009. http://umaclib3.umac.mo/record=b2120009.