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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.
11

An exploratory study of parents’ experiences of their teenagers’ text messaging

Mukasano, Epiphanie January 2014 (has links)
Magister Artium (Child and Family Studies) - MA(CFS) / Today the mobile phone plays a vital role in social life across the globe. For many teenagers and young adults in particular, this device forms an integral part of their daily communication, with text messaging being one of their preferred modes of social interaction. Researchers across the globe have studied various facets of this phenomenon but he main focus has been on this mode of communication in peer relationships. From a family systems perspective, the current qualitative study intended to explore how parents experience their teenagers’ text messaging in terms of communication and relationships with their teenagers, and how parents regulate this pervasive practice. To this end, data were collected by means of one-on-one interviews among eleven parents (eight mothers and three fathers) in Cape Town, South Africa, using a semi-structured interview schedule. With the participants’ permission, the sessions were tape-recorded; data were transcribed, content analysed, and patterns and themes identified according to Creswell’s (2009) steps. Participants expressed a range of experiences, from positive to negative, not only of text messaging, but of their teenagers’ use of mobile phones in general. Among the positives, it was the sense of security the devices gave parents, and the possibility of communicating easily, quickly and at affordable cost and at the same time monitoring their children at a distance. The negatives were mainly related to the misuse/and overuse of the mobile phones. The study suggests that parents were aware of some of the dangers associated with mobile phones, such as bullying, sexting, texting while driving, overuse at the expense of family, studying and sleeping times, and home chores. It also reveals that girls were more at risk, especially when it came to mobile bullying and sexting. Some parents came up with suggestions on dealing with mobile phones and text messaging-related problems. Furthermore, the study is indicative of a predominantly authoritative parenting style whereby parents successfully limited these dangers by regulating the use of their teenagers’ mobile phones. However, for some, finding the balance, especially between parental control and teenagers’ privacy, proved to be a challenge. Moreover, while expressing the need for mobile internet, especially for teenagers’ school work, the majority of participants showed concern about having it under control. The study concludes that text messaging can be used to enhance communication and relationships between parents and their teenagers. It recommends educating the latter about the dangers of mobile phones and the former to monitor their use, while at the same time negotiating teenagers’ freedom.
12

Trusted Mobile Overlays

Robertson, Robert Scott 13 December 2010 (has links)
Sensitive information is increasingly moving online and as data moves further from the control of its owner, there are increased opportunities for it to fall into malicious hands. The Web is comprised of three untrusted components where there is a risk of information compromise: networks, service providers, and clients. This thesis presents Trusted Mobile Overlays: a system that leverages trusted mobile devices to protect users from these untrusted components of the Web, while minimizing deployment difficulties. It presents a high-level design of the system as well as a prototype that implements the design.
13

Essays on telecommunications demand and regulatory policies

Mothobi, Onkokame January 2017 (has links)
This thesis employs models of homogenous and differentiated products to empirically investigate the demand for mobile phone services in Sub-Saharan African countries. The thesis consists of a short introductory chapter, three self-contained empirical chapters, and a summary chapter. In Chapter 2, we use survey data conducted in 2011 in eleven countries in Sub-Saharan African to analyze how the availability of physical infrastructure influences the adoption of mobile phones and usage of mobile services. The availability of physical service infrastructure is approximated by data on night-time light intensity in the areas in which survey respondents reside. After controlling for a number of individual and household characteristics including disposable income, we find that adoption of mobile phones is higher in areas with better physical infrastructure. However, in the group of mobile phone adopters, the use of mobile phones for mobile financial transactions is negatively influenced by the level of infrastructure. Mobile phone users who live in areas with poor infrastructure are more likely to rely on mobile phones to make financial transactions than individuals living in areas with better infrastructure. On the other hand, the use of mobile phones to access services such as email, skype, social media networks and Internet browsing is not dependent on the availability of physical infrastructure. Our results support the notion that mobile phones improve the livelihoods of individuals residing in remote areas by providing them with access to financial services which are otherwise not available physically. Chapter 3 examines the effect of mobile number portability (MNP) on own- and cross-price elasticities. Using quarterly data for 28 mobile operators in seven Sub-Saharan Africa countries between 2010Q4 to 2014Q4 to estimate a differentiated products demand model, we find that MNP increased own-price elasticities of demand in countries that have implemented the facility. This increase in price elasticities may be a result of a reduction in switching costs between operators. On average, the introduction of MNP increases own-price elasticities by 0.47 in absolute value. We compare the level of price elasticities before and after the implementation of MNP in Ghana and Kenya, which implemented this policy in the time period of our study. Our results suggest that in Ghana, MNP increased own-price elasticities by an average of 0.35 in absolute terms from an average value across firms and over time of -0.74. In Kenya, the introduction of MNP increased own-price elasticities by an average of 0.21 in absolute terms from a lower average value across firms and over time of -0.39. However, we find that in Kenya and Ghana the average own-price elasticities remained small even after the implementation of MNP relative to other countries without MNP in place. Thus, our results suggest that MNP is not the ultimate solution for increasing competitiveness within the mobile industry. While in Chapter 3 we use a product differentiated model of demand, in Chapter 4 we make assumptions that allow us to use a homogenous model of demand to examine the effect of regulatory policies on mobile retail prices. Using aggregated quarterly data for eight African countries for the period 2010:Q4 to 2014:Q4, we estimate structural demand and supply equations. We find that mobile termination rates (MTR) have a significant positive impact on mobile retail prices. A decline in average MTR of 10% decreases average mobile retail prices by 2.5%. On the other hand, MNP has an insignificant effect on price and subscriptions in selected African countries. This may be due to inadequate implementation of MNP, which subsequently lead to low demand for porting numbers. The average market conduct in the mobile telecommunications industry for selected African countries can be approximated by Cournot Nash equilibrium. In Chapter 4 we find price elasticities that are closer to 1 in absolute terms. The price elasticity, however, is estimated at an average of -0.27 for Sub-Saharan Africa countries in Chapter 4. We attribute this inconsistency to the different assumptions made in each chapter.
14

Quantification of the parametric uncertainty in the specific absorption rate calculation of a mobile phone / Quantification de l'incertitude paramétrique dans le calcul de débit d'absorption spécifique d'un téléphone mobile

Cheng, Xi 15 December 2015 (has links)
La thèse porte sur la quantification d'incertitude de paramètres (Uncertainty Quantification ou UQ) dans le calcul du débit d'absorption spécifique (Specific Absorption Rate ou SAR) de téléphones mobiles. L'impact de l'incertitude, ainsi le manque de connaissances détaillées sur les propriétés électriques des matériaux, les caractéristiques géométriques du système, etc., dans le calcul SAR est quantifiée par trois méthodes de calcul efficaces dites non-intrusives : Transformation non parfumée (Unscented Transformation ou UT), collocation stochastique (Stochastic Collocation ou SC) et polynômes de chaos non-intrusifs (Non-Intrusive Polynomial Chaos ou NIPC).Ces méthodes sont en effet appelées méthodes non intrusives puisque le processus de simulation est tout simplement considéré comme une boîte noire sans que ne soit modifié le code du solveur de simulation. Leurs performances pour les cas de une et deux variables aléatoires sont analysées dans le présent travail. En contraste avec le procédé d'analyse d'incertitude traditionnel (la méthode de Monte Carlo ou MCM), le temps de calcul devient acceptable. Afin de simplifier la procédure UQ pour le cas de plusieurs entrées incertaines, il est démontré que des incertitudes peuvent être combinées de manière à évaluer l'incertitude sur les paramètres de la sortie.Combiner des incertitudes est une approche généralement utilisée dans le domaine des mesures, et ici, il est utilisé dans le calcul du SAR pour la situation complexe. Une des étapes nécessaires dans le cadre de l'analyse d'incertitude est l'analyse de sensibilité (Sensitivity Analysis ou SA), qui vise à quantifier l'importance relative de chaque paramètre d'entrée incertain par rapport à l'incertitude de la sortie. La méthode reposant sur le calcul des indices de sensibilité de Sobol est employée, ces indices étant évalués par un développement en polynômes de chaos, au lieu d'utiliser la méthode de Monte-Carlo dans le calcul SAR. Les résultats des investigations sont présentés et discutés.Afin de faciliter la lecture, des notions élémentaires de débit d'absorption spécifique, de modélisation, d'incertitude dans la modélisation, de théorie des probabilités, et de calcul SAR par l'un des solveurs de simulation sont proposés dans l'Introduction (chapitre 1). Puis l'usage des méthodes non-intrusives UQ telles que UT, SC et NIPC, et l'application de la méthode des indices de Sobol pour l'analyse de sensibilité dans le calcul SAR est présentée dans les chapitres 2 et 3. Dans le chapitre 4, une autre approche d'utilisation des polynômes de chaos est fournie, et elle est utilisée dans le domaine temporel par l'intermédiaire d'un code de différences finies (Finite Difference-Time Domain ou FD-TD). Puisque le code FD-TD dans le solveur de simulation peut en effet être modifié, c'est le développement en polynômes de chaos intrusifs, étudié en détail par un certain nombre de scientifiques déjà, qui est considéré. Dans le chapitre 5, les conclusions et un aperçu des travaux futurs sont fournis. / This thesis focuses on parameter uncertainty quantification (UQ) in specific absorptionrate (SAR) calculation using a computer-aided design (CAD) mobile phone model.The impact of uncertainty, e.g., lack of detailed knowledge about material electricalproperties, system geometrical features, etc., in SAR calculation is quantified by threecomputationally efficient non-intrusive UQ methods: unscented transformation (UT),stochastic collocation (SC) and non-intrusive polynomial chaos (NIPC). They are callednon-intrusive methods because the simulation process is simply considered as a blackboxwithout changing the code of the simulation solver. Their performances for thecases of one and two random variables are analysed. In contrast to the traditionaluncertainty analysis method: Monte Carlo method, the time of the calculation becomesacceptable. To simplify the UQ procedure for the case of multiple uncertain inputs, it isdemonstrated that uncertainties can be combined to evaluate the parameter uncertaintyof the output. Combining uncertainties is an approach generally used in the field ofmeasurement, in this thesis, it is used in SAR calculations in the complex situation. Oneof the necessary steps in the framework of uncertainty analysis is sensitivity analysis (SA)which aims at quantifying the relative importance of each uncertain input parameterwith respect to the uncertainty of the output. Polynomial chaos (PC) based Sobol’indices method whose SA indices are evaluated by PC expansion instead of Monte Carlomethod is used in SAR calculation. The results of the investigations are presented anddiscussed.In order to make the reading easier, elementary notions of SAR, modelling, uncertaintyin modelling, and probability theory are given in introduction (chapter 1). Thenthe main content of this thesis are presented in chapter 2 and chapter 3. In chapter 4,another approach to use PC expansion is given, and it is used in the finite-differencetime-domain (FDTD) code. Since the FDTD code in the simulation solver should bechanged, it is so-called intrusive PC expansion. Intrusive method already investigatedin details in other people’s thesis. In chapter 5, conclusions and future work are given.
15

The Impact of Mobile Money on Saving in Sub-Saharan Africa

Ruh, Carolyn January 2017 (has links)
Thesis advisor: S. Anukriti / Since the launch of M-PESA in 2007, mobile money has created the potential to increase financial inclusion by providing a safe and convenient place to store wealth. This paper analyzes the impact of mobile money on savings practices in Sub-Saharan Africa. Using 2015 survey data from Uganda, Kenya, and Tanzania, I find that mobile money account holders are 10.9 percent more likely to save than non-account holders, holding constant other characteristics. Mobile money has a positive and significant impact on saving for daily consumption, for protection against income shocks, and for business and education investments. In addition, I find that mobile money is a complement to formal savings (bank accounts) and a substitute for informal savings. By increasing saving, mobile money better enables individuals to rely on savings in the event of a negative income shock. These results are consistent with a policy agenda that promotes financial inclusion by increasing access to mobile technologies. / Thesis (BA) — Boston College, 2017. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Departmental Honors. / Discipline: Economics.
16

[en] MOBILE TELECOMMUNICATIONS: VALUE PERCEPTIONS ON SERVICES BUNDLING / [pt] TELEFONIA MÓVEL: A PERCEPÇÃO DE VALOR NOS PACOTES DE SERVIÇOS

VINICIUS VIDAL DE ALMEIDA 20 May 2005 (has links)
[pt] Esta pesquisa procura entender melhor de que forma as operadoras de telefonia móvel podem configurar suas ofertas de pacotes de produtos e serviços, através de um estudo de percepção de valor por parte dos clientes que já utilizam os serviços. Através de questionários estruturados, procurou-se avaliar a questão da percepção de valor dos usuários, examinando a compensação entre o benefício que se recebe e o sacrifício dispendido para obter esses benefícios. Apesar de o preço ser, na maioria das vezes, o lado do sacrifício na relação de valor, os resultados mostram que os usuários estão dispostos a desembolsar uma quantia até 50 por cento maior para adquirir serviços cujas características sejam mais adequados a seus padrões de uso. / [en] The objective of this research is to understand how mbile phone operators can set their service bundling offers. An exploratory study, followed by a survey made through structured questionaries were done in order to evaluate the customers value perceptions. Value perceptions here is defined as the trade-off between the perceived benefits and the perceived sacrifice to obtain a given benefit. Although most of the times price is the sacrifice side on the perceived value relationship, the results show that on average the customers are willing to pay 50 percent more to have benefits that better fit and control their use standards.
17

Mobile Enhancement of Motivation in Schizophrenia: A Pilot Trial of a Personalized Text-Message Intervention for Motivation Deficits

Lauren Luther (6685082) 16 October 2019 (has links)
<p>Motivation deficits remain an unmet treatment need in schizophrenia. Recent preclinical research has identified novel mechanisms underlying motivation deficits, namely impaired effort-cost computations and reduced future reward-value representation maintenance, that may serve as more effective treatment targets to improve motivation. The main aim of this study was to test the feasibility and preliminary effectiveness of a translational mechanism-based intervention, MEMS (Mobile Enhancement of Motivation in Schizophrenia), which leverages mobile technology to target these mechanisms with text-messages. Fifty-six participants with a schizophrenia-spectrum disorder were randomized to MEMS (<i>n</i> = 27) or a control condition (<i>n</i> = 29). All participants set recovery goals to complete over eight-weeks. The MEMS group also received personalized, interactive text-messages each weekday to support motivation. Retention and engagement in MEMS was high: 92.6% completed 8 weeks of MEMS, with an 86.1% text-message response rate, and 100% reported that they were satisfied with the text-messages. Compared to the control condition, the MEMS group had significantly greater improvements in interviewer-rated motivation and anticipatory pleasure and obtained significantly more recovery-oriented goals at the end of the 8-week period. There were no significant group differences in performance-based effort-cost computations and future reward-value representations, self-reported motivation, quality of life, functioning, or additional secondary outcomes of positive symptoms, mood symptoms, or neurocognition. Results suggest that MEMS is feasible as a relatively brief, low-intensity mobile intervention that could effectively improve interviewer-rated motivation, anticipatory pleasure, and recovery goal attainment in those with schizophrenia-spectrum disorders. </p>
18

Nouvelles formes de communication - nouvelles formes de communauté : (les téléphones cellulaires et les cultures contemporaines des jeunes en Bulgarie) / NEW FORMS OF COMMUNICATION - NEW FORMS OF COMMUNITY : (CELL PHONES AND CONTEMPORARY YOUTH CULTURES IN BULGARIA)

Neykova, Niya 11 July 2014 (has links)
Le but de notre thèse est d’analyser par le moyen des approches interdisciplinaires «douces» des Cultural Studies les pratiques d’utilisation des téléphones portables par les jeunes bulgares (de la génération née après la chute du communisme dans le pays) en tant que bases non seulement de restructuration, mais aussi de création de nouveaux types de micro cultures juvéniles. Nous faisons l’hypothèse que les téléphones portables changent les conditions traditionnelles et les moyens d’exprimer une identité, de préserver l’intégrité d’un groupe d’appartenance, de construire une hiérarchie et des formes d’autorité. D’abord nous présentons le téléphone portable dans la perspective de l’imaginaire social, par les récits qui se reproduisent dans les produits de la culture de masse. Ensuite nous analysons les interprétations que les utilisateurs eux-mêmes donnent aux téléphones portables, ainsi que les moyens dont ils se servent pour créer de nouveaux types de relations sociales ou bien pour légitimer les anciennes, tout en nuançant certaines différences d’âge, de sexe, de statut social dans l’utilisation. A la fin nous montrons que les téléphones portables favorisent une forme de communauté spécifique, notamment l’individualisme en réseau, qui promut un individu capable de choisir et gérer ses loyautés et ses appartenances en tout temps et à tout lieu. Le téléphone portable est la technologie la plus intime, dont l’obtention est considérée comme un rite de passage qui intègre l’individu à la société de communication et à ses idéologies de transparence et de care et qui contribue ainsi à la « domestication » des situations qui lui arrivent. / The aim of this thesis is to analyze the practices of mobile phone use among young Bulgarians (the generation born after the fall of communism in the country), by using the « soft » interdisciplinary approaches of Cultural Studies. These are practices which are bases not only for restructuring of micro cultures, but also for the appearance of new ones. We assume that mobile phones are changing the traditional conditions and ways of expressing identity, of preserving the integrity of a group of belonging, of building hierarchies and forms of authority. In the first place we present the mobile phone in the perspective of the social imaginary, by summarizing repetitive discourses in the products of mass culture. Afterwards we analyze the interpretations that users themselves give to mobile phones, and the means they exploit to create new kinds of social relationships or to legitimize the existing ones, while taking into consideration certain differences in use related to age, gender and social status. Finally we show that mobile phones encourage a specific form of community, the networked individualism, which promotes an individual able to choose and manage his loyalties and his allegiances at any time and at any place. The mobile phone is the most intimate technology. Its acquisition is considered to be a rite of passage that marks the transition to the communication society and its ideologies of transparence and care, and which contributes also to the « domestication » of the situations that happen.
19

Broadcast for one: paging and network communication

Morton, Benjamin Allen 01 December 2018 (has links)
This dissertation explores the history and culture of a mobile communication device and practice that has been superseded by today’s networked communication devices. The pager—known later in the 1980s and 1990s as a beeper—has a longer history than most assume. In the early 1950s the device was not a distinct technology in its own right, but a haphazard combination of existing communications technologies: telegraphy, telephony, radio broadcasting, answering services, and hearing aids. These technological origins, and the cultures that support them, are important for broadcast and telecommunications historians, as well as media history and theory in general, for three reasons. First, research on the pager fills a gap in telecommunications history that typically begins with Bell’s wired telephone and ends with wireless mobile car-phones and, later, cellular telephones. Second, the pager’s history contributes to the limited scholarship that has emphasized radio’s many directions after the major broadcast networks left radio for larger television audiences in the late 1940s and early 1950s. Being in-between telephone and radio technology has given the pager somewhat of an identity crisis for historians. Yet this is a silver lining for communication theorists to think about the connection between a medium’s physical form (e.g., a radio is a receiving device that can’t talk back) and its communication form (e.g., a pager was once known as a radio that you would use with the telephone to talk back). Lastly, the pager is not just a technological device, but the embodiment of a rarely discussed form of communication: paging. This project investigates the history of paging as a cultural technique and communication practice. While early pagers utilized both broadcast and telecommunications techniques, paging as a form of communication does not fall clearly within either of those categories. Like being paged over a public intercom system, early paging systems broadcast a message (from one to many) in order to grab the attention of a single individual (one out of many). This form of communication, this project argues, is fundamental for understanding the many contemporary discussions over the publicly-private and privately-public nature of today’s social media services.
20

Driving advertising into mobile mediums : Study of consumer attitudes towards mobile advertising and of factors affecting on them

Pietz, Michal, Storbacka, Lauri January 2007 (has links)
<p>The high penetration rate of mobile phones along with the recent technological development has created a whole new marketing medium named mobile advertising filled with possibilities for the advertisers. Earlier studies have although indicated the success of this new advertising channel to depend on user acceptance of receiving mobile ads. Wherefore a study of consumer attitudes towards mobile advertising can be considered necessary in order to create a lucrative business. Even though this topic is relatively new several studies have already been gathered concerning user attitudes towards mobile advertising, mostly in Asian countries. Our paper aims to fill up the research gap by targeting the research to young adults in Sweden and providing thus with a study on young adult attitudes towards mobile advertising and the factors affecting them, in Sweden.</p><p>To be able to see if any relation between existing literature and empirical data exists four hypotheses have been constructed. This paper has identified user acceptance of advertising, user-based characteristics, advertising characteristics, as a well as mobile service characteristic to be main consumer acceptance drivers of mobile adverting. The four hypotheses set up for the paper could be confirmed with the help of a Pearson correlation test, which showed a significant relationship between all tested variables and a weak positive correlation. The relations are though weaker than the previous literature declares. Further results of this paper indicates that users are in general negative towards mobile advertising, and that permission and incentive based services most likely are to influence consumer attitudes towards the service.</p>

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