Tesi: "Cell phone systems Radio"

1

Zheng, Zhihua, e 鄭智華. "Dynamic channel assignment for cellular mobile radio communication systems". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B31246333.

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2

Chu, Man Kin. "A hybrid approach for mobile location estimation in cellular radio networks". HKBU Institutional Repository, 2006. http://repository.hkbu.edu.hk/etd_ra/672.

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3

Lee, See Taur. "Quad-band global system for mobile communications complementary metal-oxide-semiconductor transmitter /". Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/6122.

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4

Thavarajah, Arunasala Iyer. "A study of fixed channel assignment algorithms for cellular mobile radio systems". Thesis, Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21241144.

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5

Zhou, Junyang. "Enhanced signal propagation models and algorithm selector for providing location estimation services within cellular radio networks". HKBU Institutional Repository, 2007. http://repository.hkbu.edu.hk/etd_ra/776.

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6

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.

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7

Raghavan, Anand. "Interference cancellation for collocated wireless radios". Diss., Available online, Georgia Institute of Technology, 2007, 2007. http://etd.gatech.edu/theses/available/etd-06272007-234911/.

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Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008.
Laskar, Joy, Committee Chair ; Cressler, John, Committee Member ; Kornegay, Kevin, Committee Member ; Tentzeris, Emmanouil, Committee Member ; Lee, Chang-Ho, Committee Member.

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8

Yoon, Seungil. "Cross-layer dynamic spectrum management framework for the coexistence of white space applications". Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/44787.

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The objective of this dissertation is to propose the cross-layer spectrum management architecture for white space applications that improves the performance the main functions of the spectrum management. In the proposed cross-layer architecture, white space network devices such as white space devices and the spectrum map server cooperate to support the extended spectrum map, the inter-cell transmit power adaptation (ITPA), and the frequency-domain coexistence beacon (FCB). Upon the cross-layer architecture, firstly, white space devices (WSDs) achieve a faster search and higher accuracy in spectrum sensing with the extended spectrum map, the extended DHCP (Dynamic Host Configuration Protocol), and the FCB. Secondly, WSDs achieve the precise selection of their operating channel in spectrum decision with the extended spectrum map and the ITPA. In spectrum sharing, thirdly, the collaboration- based spectrum sharing with the ITPA achieve more accommodation of WSDs by increasing the number of channels shared between WSDs. Finally, WSDs with the FCB and the extended spectrum achieve effective spectrum mobility by obtaining the occupancy-status of channels precisely.

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9

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/.

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10

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/.

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11

Parameswaran, Subramanian T. "Software for site specific propagation prediction". Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06232009-063433/.

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12

VINHOZA, TIAGO TRAVASSOS VIEIRA. "RADIO RESEARCH MANAGEMENT TECHNIQUES FOR HIERARCHICAL CELL SYSTEMS". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2003. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=4460@1.

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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
Sistemas de celulares de múltiplas camadas (hierarquizados) são úteis para acomodar densidade alta de tráfego mantendo a qualidade de serviço. Estes sistemas procuram agregar as vantagens dos sistemas micro e macrocelulares que são respectivamente: o aumento da capacidade do sistema e a carga de sinalização da rede. Neste trabalho são analisados aspectos de projeto e desempenho de estruturas hierarquizadas como: compartilhamento do espectro entre as camadas de micro- células e macro-células bem como o desempenho de diferentes estratégias de handoff entre essas camadas. Um outro objetivo do trabalho foi o desenvolvimento de uma ferramenta simples de simulação capaz de testar as diversas estratégias de handoff e o desempenho do sistema para diferentes soluções para a distribuição dos recursos de rádio entre camadas.
Multilayer cell systems are useful to accommodate high traffic densities while still satisfying the QoS requirements. These systems combine the advantages of microcellular and macrocellular systems which are: the increase of system capacity and the reduction of the number of handoffs, hence decreasing the signaling load. This work address design aspects such as spectrum sharing between the macrocell and microcell layers and the performance of different handoff strategies considering both layers. Another goal of this work was the development of a simple, but realistic, simulation tool which will allow obtaining the radio resources management results here presented.

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13

Saunders, Lewis O. "The relationship between cell phone use and identity theft". ScholarWorks, 2011. https://scholarworks.waldenu.edu/dissertations/1123.

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The growth of mobile phone use has paralleled increased reports of identity theft. Identity theft can result in financial loss and threats to a victim's personal safety. Although trends in identity theft are well-known, less is known about individual cell phone users' attitudes toward identity theft and the extent to which they connect it to cell phone use. The purpose of this qualitative study was to determine how cell phone use is affected by attitudes toward privacy and identity theft. The study was based on social impact theory, according to which people's attitudes and behavior are affected by the strength and immediacy of others' attitudes and behavior. The research questions concerned the extent to which participants connected cell phone use with decreasing privacy and increasing cybercrime, how the use of biometrics affected cell phone users' attitudes and behavior, and what steps can be taken to reduce the misuse of private information associated with cell phone use. Data collection consisted of personal interviews with representatives from 3 groups: a private biometrics company, individual cell phone users who earn more than {dollar}55,000 a year, and individual cell phone users who earn less than {dollar}55,000 a year. Interviews were transcribed and coded for themes and patterns. Findings showed that interviewees were more likely to see identity theft as a problem among the public at large than in the industries in which they worked. Participants recommended a variety of measures to improve cell phone security and to reduce the likelihood of identity theft: passwords, security codes, voice or fingerprint recognition, and encryption. The implications for positive social change include informing government officials and individual users about the use and abuse of cell phones in order to decrease violations of privacy and identity theft while still promoting national security.

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14

Fu, Lucy. "The usability of mobile messaging systems a dissertation submitted to Auckland University of Technology in partial fulfillment of the degree of Master of Business, 2006". Full Dissertation. Abstract, 2006.

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15

Wang, Bin. "Mobile location-based services in New Zealand a dissertation (45 points) submitted to Auckland University of Technology in partial fulfillment of the requirement of the degree of Master of Computer and Information Sciences, 2008". Abstract. Full dissertation, 2008.

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Dissertation (MCIS - Computer and Information Sciences) -- AUT University, 2008.
Includes bibliographical references. Also held in print (vi, 52 leaves ; 30 cm.) in City Campus Theses Collection (T 621.38456 WAN)

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16

Abaii, Mohammad. "Multi-cell radio resource management for future cellular systems". Thesis, University of Surrey, 2009. http://epubs.surrey.ac.uk/843425/.

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Future mobile communications systems will be designed to support a wide range of data rates with complex and conflicting quality of service requirements. It is becoming more challenging to optimize radio resource management and maximise the system capacity whilst meeting the required quality of service from users' point of view. Traditional techniques have approached this problem by mainly focusing on resources within a cell and to large extent ignoring effects of multi-cell architecture leading to non uniform and unstable capacity across the network. This thesis first investigates the potential performance improvements obtained by developing novel distributed scheduling algorithms thereby highlighting the shortcomings of conventional single-cell scheduling techniques in a multi-cell system. It was found that distributed scheduling can achieve superior performance (up to 30% increased cell throughput) compared to conventional one in low/medium system loading. However, there is little advantage in case of heavily loaded system. The main achievement in this thesis is addressing this problem by proposal of a novel technique called Load Matrix, setting a new direction for future research on resource scheduling strategies in a multi-cell system. LM facilitates joint management of interference within and between cells for efficient allocation of radio resources. Simulation results provided show significant improvement in the resource utilization and overall network performance. Using LM technique, the average cell throughput can be increased between 30% to 50%. Results also show that maintaining cell interference within a margin as opposed to a hard target, can significantly improve resource utilization over time (longevity) and over the cells (uniformity). The thesis also compares the effect of ideal LM with practical and implementable versions with channel gain errors, information delay, and reducing LM database to adjacent cells. The conclusion was interesting as the performance degradation in practical LM compared to ideal LM was found to be negligible.

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17

O'Rourke, William Thomas. "Real-world evaluation of mobile phone speech enhancement algorithms". [Gainesville, Fla.] : University of Florida, 2002. http://purl.fcla.edu/fcla/etd/UFE0000585.

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18

Lawton, Michael C. "Prediction modelling of radio channnel characteristics for small cell systems". Thesis, University of Bristol, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386019.

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19

Pustay, Steven J. "Cell phones and cinema filmic representations of mobile phone technology and new agency /". Ohio : Ohio University, 2007. http://www.ohiolink.edu/etd/view.cgi?ohiou1180537475.

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20

Inman, Michael Christopher. "An investigation into the extended use of mobile phone technology in the cellular industry in Port Elizabeth". Thesis, Nelson Mandela Metropolitan University, 2004. http://hdl.handle.net/10948/247.

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While experiencing exponential growth worldwide, Information and Communication Technologies (ICTs) are key factors in business today. The ubiquitous nature of the mobile phone in South Africa and the use of wireless technologies facilitate business in areas where current fixed infrastructure is limited or non-existent, thereby aiding in the development of rural areas. This descriptive study determines what factors will extend the use of mobile phone technology in business. The literature indicates business advantage can be gained from incorporating technology into a strategic framework but in so doing must consider the complexities of the technology and its lifecycle. Currently, e-mail and Internet access would be the most likely applications of data use via Global System for Mobile Communications (GSM). As a technology-based study the methodology used e-mail to deliver a survey targeting staff from the three cellular network operators in Port Elizabeth. The mobile industry and Port Elizabeth were both considered good indicators of technology use and the progression of infrastructure throughout South Africa. The findings indicate that although most mobile phones have the features required by users, the current use of associated data applications is low. Email is the most appropriate application and expected to be significant in 2006. The technology is of strategic importance and can be applied to make idle time productive. Successful use depends on the removal of barriers. In the case of e-mail and Internet access; the most significant of these is the complexity of the initial set-up. Despite the complexity of technology evolution and the challenges of effective business application, substantial gains can be still be realised. Currently, technology is best deployed to meet specialised needs. The expected introduction of third generation technologies herald’s higher data transfer rates, providing the opportunity for more generalised application in business in the immediate future.

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21

Da, Silveira Marthinus Willem. "Analysis of spatially distributed adaptive antenna array systems in cellular networks". Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-06032005-090336/.

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22

Cranfield, Charles G., e ccranfield@swin edu au. "A study of the effects of mobile-phone type signals on calcium ion levels with a human leukaemic T cell line". Swinburne University of Technology, 2001. http://adt.lib.swin.edu.au./public/adt-VSWT20050322.124601.

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The work presented here outlines experiments done using a novel RF exposure chamber. This device allows biological cells to be exposed to microwave radiation similar to those emitted by mobile telephones, whilst imaging them using a laserscanning confocal microscope. Jurkat E6.1 T lymphocytes in the exposure chamber were kept within �0.5�C of 37�C, allowing for the investigation of possible athermal effects of microwave energies. These cells were loaded with the fluorescent probe Fluo-3 AM, which is specific for calcium ions, and were monitored over two 10minute periods. The first period being a control period, the second being a period where the cells were either exposed to RF energy or sham exposed. Another 5min imaging period was for the positive control,where maximal fluorescence can be achieved by the addition of the ionophore A23187. 5 different conditions for cell exposure were investigated. Both continuous wave 900MHz and continuous wave 900MHz pulse modulated at 217Hz exposures were carried out on cells that were either unactivated, or those that were activated by the mitogen phytohaemaglutinin (PHA). For these 4 conditions the average Specific Absorption Rate (SAR) was calculated to be 1.5W/kg. A group of unactivated cells were also exposed to continuous wave 900MHz energy with an average SAR calculation of 7.5W/kg. Results showed that no significant changes in calcium ion levels occurred when averaged fluorescence slopes were compared between RF exposed cells and the control period. The mean change in slopes exposed/sham period � control period)between cells that were exposed and those sham exposed also showed no significant difference. Following an inference made in the work of Galvanovskis et al. (1999)1 who showed there is a change in the calcium ion oscillation spectrum as a result of 50Hz magnetic fields, a measure of the mean frequencies of all cells was determined using a Fast Fourier Transform (FFT) analysis. The change in the average mean frequencies in cells was then measured for all conditions. Of statistical significance was the change in average mean frequency between the control period and the sham/exposed period between cells that were exposed and those sham exposed, when cells were activated by PHA. The results also showed that there was an overall drop in average mean frequency as a result of RF exposure. Assuming there is a biological significance to the findings of this thesis, careful analysis of the calcium dynamics of tissue samples and cell types associated with RF exposure from mobile phones would need to be carried out to determine what they are. This was unfortunately beyond the scope of the present study.

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23

Wong, Wing-lun Alan. "The development and competition of the mobile phone industry in Hong Kong /". Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19872124.

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24

Wong, Jason Pei Wai. "Institutions, knowledge acquisition and cooperation : innovation in the emerging domestic mobile phone industry in China /". View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?SOSC%202004%20WONG.

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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004.
Includes bibliographical references (leaves 71-76). Also available in electronic version. Access restricted to campus users.

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25

Eriksson, Evanjeline. "A Case Study About Cell Phone Use by People in Rural Kenya". Thesis, Växjö University, School of Mathematics and Systems Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-2023.

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The arrival of the cell phone in rural areas has taken Kenya by storm. It has turned out to be such an amazing transition happening since most people in the start, did not reckon its capacity to gradually become a lifestyle choice. It has certainly changed the way people communicate and becoming a natural necessity for people of Kenya. This can be seen from the numbers of cell phone units sold in the past years. The cell phones in Kenya have gone from 1 million in 2002 to 6.5 million in 2006. Some of this boost has found their way into the rural areas of Kenya and that is what this thesis focuses on. Through a qualitative research approach presented as a case study provide both vigorous descriptions and exiting information. The case study is based mainly on material from telephone interviews that were carried out with a selected sample of the population living in the countryside to obtain their points of view. In addition some opinions received in email form from an organization based in the western part of Kenya is included. A related email questionnaire was administered to one of the companies that sell cell phones in Kenya. Reference has been made to previous research to present some insightful frame of reference on this subject. In conclusion the people in rural parts of Kenya use the short messaging service (SMS) as the most cost effective way of communication. Furthermore, the M-Pesa function on that enables users to make money transactions is also widely used since most people in these areas do not have a bank account. The cell phone has transformed the job market and had a tremendous impact on running a business and made it easier to be available when looking for jobs. It is clear that the cell phone has brought practical, social and economical change and contributing to cultural enhancement. There is however future needs as to solve the battery charging which is a main problem that rural inhabitant have to deal with. This thesis finally shows that the penetration of the cell phone in rural Kenya is of great success. The cell phone is a technique to bridge the gap between cities and rural areas in Kenya.

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26

Ellenbeck, Jan [Verfasser]. "Radio Resource Management and System Spectral Efficiency in LTE Multi-Cell Systems / Jan Ellenbeck". München : Verlag Dr. Hut, 2015. http://d-nb.info/1076437621/34.

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27

Rooney, Daniel J. "The effects of corruption and governance on telecommunications demand an econometric analysis /". Ohio : Ohio University, 2006. http://www.ohiolink.edu/etd/view.cgi?ohiou1154546000.

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28

Haenssgen, Marco Johannes. "Mobile phone diffusion and rural heathcare access in India and China". Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:3f48fc8b-5414-4851-926b-07a57eed6cfe.

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Three decades of mobile phone diffusion, thousands of mobile-phone-based health projects worldwide ("mHealth"), and tens of thousands of health applications in Apple's iTunes store, but fundamental questions about the effect of phone diffusion on people's healthcare behaviour remain unanswered. Empirical, theoretical, and methodological gaps in the study of mobile phones and health reinforce each other and lead to simplifying assumptions that mobile phones are a ubiquitous and neutral platform for interventions to improve health and healthcare. This contradicts what we know from the technology adoption literature. This thesis explores the theoretical link between mobile phone diffusion and healthcare access; develops and tests a new multidimensional indicator of mobile phone adoption; and analyses the effects of phone use on people's healthcare-seeking behaviour. My mixed methods research design - implemented in rural Rajasthan (India) and Gansu (China) - involves qualitative research with 231 participants and primary survey data from 800 persons. My research yields a qualitatively grounded framework that describes the accessibility and suitability of mobile phones in healthcare-seeking processes, the heterogeneous outcomes of phone use and non-use on healthcare access, and the uneven equity consequences in this process. Quantitative analysis based on the framework finds that mobile phone use in rural India and China increases access to healthcare, but it also invites more complex and delayed health behaviours and the over-use of scarce healthcare resources. Moreover, increasing phone-aided health action threatens to marginalise socio-economically disadvantaged groups further. I present here the first quantitative evidence on how mobile phone adoption influences healthcare-seeking behaviour. This challenges the common view that mHealth interventions operate on a neutral platform and draws attention to potential targeting, user acceptance, and sustainability problems. The framework and tools developed in this thesis can support policy considerations for health systems to evaluate and address the healthcare implications of mobile phone diffusion.

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29

Kildare, Cory A. "Infants' Perceptions of Mothers' Phone Use: Is Mothers' Phone Use Generating the Still Face Effect?" Thesis, University of North Texas, 2017. https://digital.library.unt.edu/ark:/67531/metadc984229/.

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Using a modified still-face procedure the present study explores 3-6-month-old infants' behavioral and physiological responses to mothers' screen distractions during mother-infant interactions. In the modified phone still-face procedure the neutral face of the traditional still face procedure was replaced with mothers' texting on their mobile phones. Infants' cortisol stress responses to mothers' device use were assessed through the collection of 3 infant saliva samples. Infants' behavioral responses including facial expressions, vocalizations, gaze and self-comforting behaviors were also explored. All mother-infant interactions were videoed recorded and coded for analysis. Thirty-four mother-infant dyads participated, average ages for mothers was 29 years and 4.4 months for infants. As predicted, infants demonstrated the changes in affect associated with the still-face effect, with significant differences in positive and negative affect during the play phases and the phone still face phase. As a whole, infants did not respond with increased cortisol responses, however, when individual differences were explored 47% responded with increased stress during mothers' phone distractions. Mother's frequency and attitudes towards device use were also assessed but were unrelated to infant responses. Implications and directions for future research are discussed.

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30

Nässla, Hans. "Intra-Family Information Flow and Prospects for Communication Systems". Licentiate thesis, Linköping University, Department of Computer and Information Science, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-5672.

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Today, information and communication technology is not only for professional use, but also for private tasks. In this thesis, the use of such technology for managing family information flow is investigated. Busy family life today, with school, work and leisure activites, makes coordination and synchronisation a burden. In what way cell-phones and Internet provides a support for those tasks is investigated, together with proposals for future technology.

The problem with coordination and synchronisation were found to be managed by a bulletin board placed at a central point at home. Besides the bulletin board, we found that calendars, shopping lists, and to-do lists are important. The families we investigated in field studies were all intensive users of both Internet and cell-phones.

Since the bulletin board played such an important role in the family life, we equipped families with cameras to be able to track what happened at those places with help of photo diaries. The field studies revealed that each family had their own unconscious procedure to manage the flow of notes on the bulletin board.

With technology, new problem will emerge. We investigated how notes on typical family bulletin boards may be visualised on a computer screen, and compared click-expand, zoom-pan and bifocal interfaces. The click-expand interface was substantially faster for browsing, and also easier to use.

An advantage of information and communication technology is that it may provide possibilities for multiple interfaces to information, and not only different terminals but also from different places. At home, a digital refrigerator door or a mobile web tablet; at work or at school, a conventional computer; when on the move, a cell-phone or a PDA. System architecture for these possibilities is presented.

Report code: LiU-TEK-LIC-2004:39.

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31

Jessop, Glenn. "Motor telephony the practices and problems of regulating mobile telephony and driving /". Swinburne Research Bank, 2007. http://hdl.handle.net/1959.3/22008.

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Thesis (PhD) - Institute for Social Research, Faculty of Life and Social Sciences, Swinburne University of Technology, 2007.
Thesis submitted in fulfillment of the requirements of the degree of Doctor of Philosophy, Institute for Social Research, Faculty of Life and Social Sciences, Swinburne University of Technology, 2007. Typescript. Includes bibliographical references (p. 208-243).

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32

Sagboze, Konzi Olivier. "Real-time detection of attendance at a venue using mobile devices". Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2676.

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Thesis (MTech (Information Technology))--Cape Peninsula University of Technology, 2017.
The implosion of the mobile phones, mobile applications and social media in recent years has triggered a great interest for more dedicated user-generated contents. Mobile users being the focal point, these modern virtual platforms depend on and live for collecting, structuring and manipulating the very fine-grained details about users' day-to-day activities. Since every human activity takes place in a geographical context, location information ranks high among the set of data to gather about user's daily life. User's specific location details can help filter content to serve and retrieve from them. Therefore, location-based services have been developed and successfully integrated into most virtual platforms in the quest for these precious data. However, location-based services do not fulfil all requirements. They depend on a range of positioning systems which show numerous limitations. None of the existing positioning systems is perfectly accurate. Today, it is therefore difficult to pinpoint a user in a venue using location-based services. Nevertheless, with the set of existing technology and techniques, it is possible to estimate and track users’ whereabouts in real-time. Providing the best possible estimation of user's position within a given venue can help achieve better user engagement. Depending on the gap of accuracy, the end result may actually match the outcome expected from perfectly accurate positioning systems. In this work, the focus is to develop a prototype positioning system which provides the best estimation of user's position in real-time in relation to a targeted venue or location. Through a series of research and comparison study, the most suited technology and techniques are objectively selected to build the intended prototype. The challenge of indoor positioning is also addressed in this work – bearing in mind the fact that this prototype is set to work accurately and efficiently in any geographical location and structure. The prototype is evaluated according to a set of predefined standard metrics, and theories are extracted to grow knowledge about this trending topic.

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Negi, Ansuya. "Analysis of Relay-based Cellular Systems". PDXScholar, 2006. https://pdxscholar.library.pdx.edu/open_access_etds/2668.

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Relays can be used in cellular systems to increase coverage as well as reduce the total power consumed by mobiles in a cell. This latter benefit is particularly useful for mobiles operating on a depleted battery. The relay can be a mobile, a car or any other device with the appropriate communication capabilities. In thesis we analyze the impact of using relays under different situations. We first consider the problem of reducing total power consumed in the system by employing relays intelligently. We find that in a simulated, fully random, mobile cellular network for CDMA (Code Division Multiple Access), significant energy savings are possible ranging from 1.76 dB to 8.45 dB. In addition to reducing power needs, relays can increase the coverage area of a cell by enabling mobiles located in dead spots to place relayed calls. We note that use of relays can increase the useful service area by about 10% with real life scenarios. We observe that in heavy building density areas there is more need of relays as compared to low building density areas. However, the chance of finding relays is greater in low building density areas. Indeed, having more available idle nodes helps in choosing relays, so we conclude that unlike present day implementations of cellular networks, the base station should admit more mobiles (beyond the capacity of the cell) even if they are not placing calls since they can be used as relays. One constraint of using relays is the potential to add interference in the same cell and in neighboring cells. This is particularly true if the relays are not under power control. Based on our analysis, we conclude that in interference limited systems like CDMA the relays have to be under power control otherwise we will reduce the total capacity by creating more dead spots. Thus, we believe that either the base station should be responsible to allocate relays or relays should be provided with enough intelligence to do power control of the downlink. Finally, we show how utility of data services can be increased by use of relays.

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34

Clawson, James. "On-the-go text entry: evaluating and improving mobile text input on mini-qwerty keyboards". Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45955.

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To date, hundreds of millions of mini-QWERTY keyboard equipped devices (miniaturized versions of a full desktop keyboard) have been sold. Accordingly, a large percentage of text messages originate from fixed-key, mini-QWERTY keyboard enabled mobile phones. Over a series of three longitudinal studies I quantify how quickly and accurately individuals can input text on mini-QWERTY keyboards. I evaluate performance in ideal laboratory conditions as well as in a variety of mobile contexts. My first study establishes baseline performance measures; my second study investigates the impact of limited visibility on text input performance; and my third study investigates the impact of mobility (sitting, standing, and walking) on text input performance. After approximately five hours of practice, participants achieved expertise typing almost 60 words per minute at almost 95% accuracy. Upon completion of these studies, I examine the types of errors that people make when typing on mini-QWERTY keyboards. Having discovered a common pattern in errors, I develop and refine an algorithm to automatically detect and correct errors in mini-QWERTY keyboard enabled text input. I both validate the algorithm through the analysis of pre-recorded typing data and then empirically evaluate the impacts of automatic error correction on live mini-QWERTY keyboard text input. Validating the algorithm over various datasets, I demonstrate the potential to correct approximately 25% of the total errors and correct up to 3% of the total keystrokes. Evaluating automatic error detection and correction on live typing results in successfully correcting 61% of the targeted errors committed by participants while increasing typing rates by almost two words per minute without introducing noticeable distraction.

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Miteche, Sacha Patrick. "A mobile phone solution for ad-hoc hitch-hiking in South Africa". Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1013340.

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The purpose of this study was to investigate the use of mobile phones in organizing ad-hoc vehicle ridesharing based on hitch-hiking trips involving private car drivers and commuters in South Africa. A study was conducted to learn how hitch-hiking trips are arranged in the urban and rural areas of the Eastern Cape. This involved carrying out interviews with hitch-hikers and participating in several trips. The study results provided the design specifications for a Dynamic Ridesharing System (DRS) tailor-made to the hitch-hiking culture of this context. The design of the DRS considered the delivery of the ad-hoc ridesharing service to the anticipated mobile phones owned by people who use hitch-hiking. The implementation of the system used the available open source solutions and guidelines under the Siyakhula Living Lab project, which promotes the use of Information and Communication Technology (ICT) in marginalized communities of South Africa. The developed prototype was tested in both the simulated and live environments, then followed by usability tests to establish the viability of the system. The results from the tests indicate an initial breakthrough in the process of modernizing the ad-hoc ridesharing of hitch-hiking which is used by a section of people in the urban and rural areas of South Africa.

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36

Wu, Sun John, e 胡新. "Mobile phone handset strategies of market leaders in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31269576.

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37

Lissai, Gidon. "Assisted GPS solution in cellular networks /". Online version of thesis, 2007. http://hdl.handle.net/1850/3671.

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38

Thoma, Berthold. "Bit error rate simulation enhancement and outage prediction in mobile communication systems". Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-09052009-040547/.

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39

Cabré-Riera, Alba 1991. "Radiofequency electromagnetic fields exposure, sleep, and neurodevelopment in preadolescents and adolescents". Doctoral thesis, Universitat Pompeu Fabra, 2011. http://hdl.handle.net/10803/670279.

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The use of mobile communication devices (e.g. mobile phones, tablets, and laptops) increased during the last few years, especially in preadolescents and adolescents. In order to function, mobile communication devices require a constant exchange of information achieved using radiofrequency electromagnetic fields (RF-EMF). Evidence is limited for potential effects of RF-EMF exposure to the brain and epidemiological studies that assessed RF-EMF exposure and its relationship with sleep and neurodevelopment are scarce. This thesis aimed to better understand the potential association between RF-EMF exposure and sleep, and RF-EMF exposure and neurodevelopment by: i) using a comprehensive RF-EMF exposure assessment (i.e. distinguish between sources with different patterns of RF-EMF exposure to the brain such as phone calls, screen activities, and environmental sources, ii) estimating the amount of RF-EMF the brain absorbs from each source and overall, ii) assessing sleep using objective measures collected with actigraphy, and iii) assessing neurodevelopment as cognitive function and brain volumes. The use of some mobile communication devices such as the tablet and problematic mobile phone use were associated with poorer sleep quality and less favourable objective sleep measures. Moreover, evening whole-brain RF-EMF dose from phone calls was associated with less favourable objective sleep measures. Regarding neurodevelopment, overall whole-brain RF-EMF dose and whole-brain RF-EMF dose from phone calls were not associated with brain volumes but whole-brain RF-EMF dose from screen activities was associated with smaller caudate volume. Finally, overall whole-brain RF-EMF dose and whole-brain RF-EMF dose from phone calls was associated with non-verbal intelligence. Given that the biological mechanism behind the observed associations between RF-EMF exposure and sleep, and RF-EMF exposure and neurodevelopment is unknown, that we found small effects sizes, and that we could not entirely disentangle between minutes of use and RF-EMF dose, our results should be interpreted with caution. We cannot discard chance finding, reverse causality, or that other non-RF-EMF factors related to the use of mobile communication devices are behind the observed associations (e.g. blue light, addiction, mental arousal or sleep displacement).
El uso de dispositivos móviles de comunicación como los teléfonos móviles, tabletas y ordenadores portátiles ha aumentado en los últimos años, especialmente en preadolescentes y adolescentes. Los dispositivos móviles de comunicación utilizan los campos electromagnéticos de radiofrecuencia (CEM-RF) para el intercambio constante de información necesario para su funcionamiento. La evidencia científica de los efectos que tiene la exposición a CEM-RF al cerebro es limitada y los estudios epidemiológicos que evalúan la exposición de CEM-RF y su relación con el sueño y el neurodesarrollo son escasos. Esta tesis tiene como objetivo entender mejor las asociaciones entre la exposición a CEM-RF y el sueño y la exposición a CEM-RF y el neurodesarrollo: i) haciendo una evaluación completa de la exposición de CEM-RF al cerebro, es decir, distinguiendo entre fuentes de CEM-RF con diferentes patrones de exposición al cerebro como las llamadas telefónicas, el uso de aparatos móviles de comunicación para actividades con pantalla y las fuentes ambientales, ii) estimando la cantidad de CEM- RF que el cerebro absorbe de cada fuente y en total, iii) evaluando el sueño utilizando medidas objetivas recogidas con actigrafia y iv) evaluando el neurodesarrollo como función cognitiva y volúmenes cerebrales. El uso de algunos dispositivos móviles de comunicación como por ejemplo la tableta y el uso problemático del teléfono móvil están associados con peor calidad y medidas objetivas del sueño. Además, hemos observado una asociación entre la dosis de CEM-RF al cerebro proveniente de las llamadas telefónicas por la tarde y peores medidas objetivas del sueño. En cuanto al neurodesarrollo, la dosis total de CEM-RF al cerebro y la dosis de CEM-RF al cerebro proveniente de las llamadas telefónicas no están asociadas con los volúmenes cerebrales, en cambio, la dosis de CEM-RF al cerebro proveniente de usos de aparatos móviles de comunicación para actividades con pantalla está asociada con un volumen más pequeño del núcleo caudado. Finalmente, la dosis total de CEM-RF al cerebro y la dosis de CEM-RF al cerebro proveniente de las llamadas telefónicas están asociadas con peor inteligencia no verbal. Teniendo en cuenta que se desconoce el mecanismo biológico que hay detrás de las asociaciones observadas entre la exposición a CEM-RF y el sueño y la exposición a CEM-RF y el neurodesarrollo, que los efectos que hemos encontrado son pequeños y que no hemos podido separar completamente entre los minutos de uso y la dosis de CEM-RF, nuestros resultados deben interpretarse con precaución. No podemos descartar hallazgo casual, causalidad inversa o que otros factores relacionados con el uso de dispositivos móviles de comunicación estén detrás de las asociaciones observadas. Por ejemplo, exposición a la luz azul, adicción a los dispositivos móviles de comunicación, excitación mental o desplazamiento del sueño.
L’ús de dispositius mòbils de comunicació com els telèfons mòbils, tauletes i ordinadors portàtils ha augmentat els darrers anys, especialment en preadolescents i adolescents. Els dispositius mòbils de comunicació utilitzen els camps electromagnètics de radiofreqüència (CEM-RF) per l’intercanvi constant d’informació necessari pel seu funcionament. L’evidència científica dels efectes que té l’exposició de CEM-RF al cervell és limitada i els estudis epidemiològics que avaluaven l’exposició de CEM-RF i la seva relació amb el son i el neurodesenvolupament són escassos. Aquesta tesi té com a objectiu entendre millor les associacions entre l’exposició a CEM-RF i el son i l’exposició a CEM-RF i el neurodesenvolupament. Per fer-ho: i) hem fet una avaluació completa de l’exposició de CEM-RF al cervell, és a dir, distingint entre fonts de CEM-RF amb diferents patrons d’exposició al cervell com les trucades telefòniques, l’ús d’aparells mòbils de comunicació per activitats amb pantalla i les fonts ambientals, ii) hem estimat la quantitat de CEM-RF que el cervell absorbeix de cada font i en total, iii) hem avaluat el son utilitzant mesures objectives recollides amb actigrafia i iv) hem avaluat el neurodesenvolupament com a funció cognitiva i volums cerebrals. L’ús d’alguns dispositius mòbils de comunicació com per exemple la tauleta i l’ús problemàtic del telèfon mòbil estan associats amb pitjor qualitat i mesures objectives del son. A més a més, hem trobat una associació entre la dosi de CEM-RF al cervell provinent de les trucades telefòniques al vespre i pitjors mesures objectives del son. En relació amb el neurodesenvolupament, la dosi total de CEM-RF al cervell i la dosi de CEM-RF al cervell provinent de les trucades telefòniques no estan associades amb els volums cerebrals, en canvi, la dosi de CEM-RF al cervell provinent d’usos d’aparells mòbils de comunicaió per activitats amb pantalla està associada amb un volum més petit del nucli caudat. Finalment, la dosi total de CEM-RF al cervell i la dosi de CEM-RF al cervell provinent de les trucades telefòniques estan associades amb pitjor la intel·ligència no verbal. Tenint en compte que es desconeix el mecanisme biològic que hi ha darrere de les associacions observades entre l'exposició a CEM-RF i el son i l'exposició a CEM-RF i el neurodesenvolupament, que els efectes que hem trobat són petits i que no hem pogut separar completament entre els minuts d'ús dels dispositius mòbils de comunicació i la dosi de CEM-RF al cervell, els nostres resultats s’han d’interpretar amb precaució. No podem descartar que les troballes siguin casuals, causalitat inversa o que altres factors relacionats amb l’ús de dispositius mòbils de comunicació estiguin darrere de les associacions observades. Per exemple, exposició a la llum blava, addicció als aparells mòbils de comunicació, excitació mental o desplaçament del son.

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40

Zhong, Li. "Testing a two-pathway model connecting mobile phone use and loneliness among Filipino domestic workers in Hong Kong". HKBU Institutional Repository, 2019. https://repository.hkbu.edu.hk/etd_oa/652.

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Although there is a long tradition of research into the relationship between technology and psychological well-being, few studies examine the relationship between mobile phone use and loneliness (Chan, 2015). Far away from their home countries and living in constrained conditions, female domestic workers in particular might experience chronic loneliness, and the mobile phone is a crucial lifeline for them. Using a face-to-face survey of 492 Filipino domestic workers in Hong Kong, this dissertation details how different uses of mobile phones are related to different types of loneliness among this vulnerable population. By differentiating between communicative and non-communicative use of the mobile phone, and between social loneliness and emotional loneliness, the results indicate that Filipino domestic workers' non-communicative use of the mobile phone could decrease their social loneliness, while communicative use neither decreases nor increases both social and emotional loneliness. This finding supports the proposition that mobile phone use is beneficial to individuals' psychological well-being and extends the existing literature on the relationship between mobile phone use and loneliness. Most importantly, there is still no a systematic framework to explain the underlying mechanism connecting mobile phone use and loneliness. Based on the technology paradox and the paradoxical impact of mobile phone use on loneliness, this dissertation develops a two-pathway model to illustrate the underlying mechanism. The first pathway postulates that mobile phone use has a positive influence on loneliness through preference for online communication and problematic mobile phone use, which is based upon the theoretical framework of Davis's (2001) cognitive-behavioral model, Caplan's (2003) theory of preference for online communication, and the literature on the bidirectional relationship between technology and psychological well-being. Grounded in the social convoy model (Kahn &Antonucci, 1980; Antonucci, 2001), the second pathway posits that mobile phone use has a negative impact on loneliness through social network availability and social support. The findings show that the two-pathway model indeed exists. In the first pathway, mobile phone use increases emotional loneliness by leading to problematic mobile phone use. In the second pathway, mobile phone use results in decreased social loneliness through increased social support or through the joint impact of social network availability and social support. This dissertation makes theoretical and practical contributions to the field of mobile phone use, not only by developing a two-pathway model to uncover the underlying mechanism connecting mobile phone use with loneliness, but also demonstrates the technology paradox and the paradoxical impact of mobile phone use on loneliness among the Filipino domestic workers in Hong Kong. It will be worthwhile to replicate and testify this two-pathway model in other populations, such as elders, adolescents, and young adults.

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Ellenbeck, Jan [Verfasser], Jörg [Akademischer Betreuer] Eberspächer e Wolfgang [Akademischer Betreuer] Utschick. "Radio Resource Management and System Spectral Efficiency in LTE Multi-Cell Systems / Jan Ellenbeck. Gutachter: Jörg Eberspächer ; Wolfgang Utschick. Betreuer: Jörg Eberspächer". München : Universitätsbibliothek der TU München, 2015. http://d-nb.info/1075317134/34.

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42

West, Philip. "A framework for responsive content adaptation in electronic display networks". Thesis, Rhodes University, 2006. http://hdl.handle.net/10962/d1004824.

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Recent trends show an increase in the availability and functionality of handheld devices, wireless network technology, and electronic display networks. We propose the novel integration of these technologies to provide wireless access to content delivered to large-screen display systems. Content adaptation is used as a method of reformatting web pages to display more appropriately on handheld devices, and to remove unwanted content. A framework is presented that facilitates content adaptation, implemented as an adaptation layer, which is extended to provide personalization of adaptation settings and response to network conditions. The framework is implemented as a proxy server for a wireless network, and handles HTML and XML documents. Once a document has been requested by a user, the HTML/XML is retrieved and parsed, creating a Document Object Model tree representation. It is then altered according to the user’s personal settings or predefined settings, based on current network usage and the network resources available. Three adaptation techniques were implemented; spatial representation, which generates an image map of the document, text summarization, which creates a tree view representation of a document, and tag extraction, which replaces specific tags with links. Three proof-of-concept systems were developed in order to test the robustness of the framework. A system for use with digital slide shows, a digital signage system, and a generalized system for use with the internet were implemented. Testing was performed by accessing sample web pages through the content adaptation proxy server. Tag extraction works correctly for all HTML and XML document structures, whereas spatial representation and text summarization are limited to a controlled subset. Results indicate that the adaptive system has the ability to reduce average bandwidth usage, by decreasing the amount of data on the network, thereby allowing a greater number of users access to content. This suggests that responsive content adaptation has a positive influence on network performance metrics.

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43

Gelincik, Samet. "Interference management in sectored cellular networks with local multi-cell processing". Electronic Thesis or Diss., Institut polytechnique de Paris, 2019. http://www.theses.fr/2019IPPAT010.

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L’exigence de débit de données dans les communications sans fil due à l’emploi de smartphones, d’ordinateurs portables, de tablettes et de capteurs augmente considérablement. Cela pose directement des demandes extraordinaires sur de précieuses ressources spectrales. Pour satisfaire la saturation attendue sur les bandes actuellement utilisées, les systèmes de communication modernes permettent une réutilisation très fréquente des fréquences spatiales et évoluent vers des réseaux hétérogènes de stations de base (BS) couvrant des zones plus petites (petites cellules). De toute évidence, un tel système souffre des conditions d’interférence intercellulaires préjudiciables, en particulier aux bords des cellules. Par conséquent, il est clairement convaincant que la gestion des interférences est un goulot d’étranglement pour les réseaux sans fil actuels et futurs. Les schémas de traitement multicellulaire (MCP) ont été principalement utilisés pour fournir aux BS des versions quantifiées des signaux d’émission / réception d’autres BS via des liaisons de liaison (permettant le décodage en cluster. Il est alors possible que les données utilisateur soient traitées conjointement par plusieurs BS) à la fois en liaison montante et en liaison descendante, imitant ainsi les avantages du MIMO virtuel. Cependant, la mise en oeuvre de MCP pour toutes les BS du réseau est assez difficile en pratique en raison de la grande complexité de calcul et des retards excessifs, même pour les grands réseaux modérés. Cependant, diviser le réseau en plusieurs clusters et les laisser coopérer au sein de chaque cluster plutôt que sur l’ensemble du réseau apporte également certains avantages du MCP en ne nécessitant que les signaux reçus locaux et le CSI local. Nous appelons ce cadre MCP local, ce qui améliore également la robustesse du réseau aux échecs de connexion et l’évolutivité. Dans cette thèse, nous avons étudié les avantages de MCP local dans la gestion des interférences pour modèle de réseau hexagonal sectorisé sous trois scénarios différents. Dans le premier, nous avons supposé que le BS peut coopérer par le biais de liaisons à capacité limitée pour un nombre donné de cycles de coopération. Nous avons proposé un nouveau schéma de regroupement pratique qui adapte la façon dont les BS coopèrent à la sectorisation des cellules. Plus haut et plus bas et limites supérieures des degrés de liberté par utilisateur (DoF) en fonction de la coopération de nombres et la capacité de raccordement a été dérivée et une analyse SNR finie a ét é effectuée. Dans le deuxième scénario, nous supposé un système cellulaire multi-cloud, o`u chaque processeur central (CP) a une puissance de traitement limitée. UNE un schéma de clustering a été proposé qui adapte l’association entre BS et CP à la sectorisation. Limite inférieure du DoF par utilisateur en fonction de la capacité de liaison, de la capacité de CP et du rapport du nombre de Le CP en nombre de BS a ét é dérivé. Dans le dernier scénario, nous avons supposé à nouveau un cellulaire basé sur plusieurs nuages et appliqué des systèmes de calcul et de transfert (CoF) et de CoF quantifiés au clustering proposé. Pour CoF quantifié, nous avons proposé une méthode pour réduire le nombre de codes de réseau imbriqués pour réduire la mise en oeuvre complexité tout en conservant une dégradation raisonnable des performances
The data rate requirement in wireless communication due to employment of smartphones, laptops, tablets and sensors is increasing drastically. This directly poses extra-ordinary demands on precious spectral resources. To satisfy with the expected saturation on the currently used bands, modern communication systems are allowing very aggressive spatial frequency reuse and moving towards heterogenous networks of base stations (BS) covering smaller areas (small cells). Evidently, such system suffer from the detrimental inter-cell interference conditions, particularly at cell edges. Therefore, it is clearly convincing that interference management is a bottleneck for current and future wireless networks. Multi-cell processing (MCP) schemes has mostly been used to provide BSs with quantized versions of the transmit/receive signals of other BSs via backhaul/fronthaul links (allowing for clustered decoding). It is then possible for user data to be jointly processed by several BSs at both uplink and downlink, hence imitating the benefits of virtual MIMO. However, the implementation of MCP for all the BSs of the network is quite challenging in practice due to large computational complexity and excessive delays even for moderately large networks. However, dividing the network into several clusters and letting them to cooperate within each cluster rather than the entire network also brings some benefit of MCP by requiring only local received signals and local CSI. We name this framework as local MCP, which also improves the robustness of the network to connection failures and scalability. In this thesis, we have investigated the benefits of local MCP in interference management for sectored hexagonal network model under three different scenarios. In the first one, we assumed that the BS can cooperate through limited capacity links for a given number of cooperation rounds. We proposed a new practical clustering scheme that adapts the way BSs cooperate to cells sectorization. Upper and lower bounds on the peruser degrees-of-freedom (DoF) as a function of number cooperation round and backhaul capacity have been derived, and finite SNR analysis has been done. In the second scenario, we assumed a multi-cloud cellular system, where each central processor (CP) has a limited processing power. A clustering scheme has been proposed that adapts the association between BSs and CPs to the sectorization. Lower bound on the per-user DoF as a function of fronthaul capacity, CP capacity and the ratio of number of CP to number of BS has been derived. In the last scenario, we assumed again a multi-cloud based cellular system, and applied compute-and-forward (CoF) and Quantized CoF schemes to the proposed clustering. For Quantized CoF, we proposed a method for reducing the number of nested lattice codes to lower the implementation complexity while keeping reasonable performance degradation

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López-Fernández, Olatz. "Problematic Internet and mobile phone use in adolescents in Barcelona and London". Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/126442.

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This thesis focuses on the development and adaptation of psychometric scales to evaluate the problematic use of Internet and the mobile phone in adolescents in Barcelona and London. It aims to describe the characteristics and patterns of this use, to categorize problematic users of either technology and to test category validity by developing the “Problematic Internet Entertainment Use Scale for Adolescents” and adapting the “Mobile Phone Problematic Use Scalefor Adolescents” (here after, PIEUSA and MPPUSA, respectively). It also proposes a statistical model to obtain predictive factors and estimates the prevalence of problematic users of both technologies so as to more effectively describe their psychological and social profile and examine the addictive nature of their use. The thesis takes the findings of five selective studies using convenience samples of more than 1000 secondary school students in Barcelona and a similar sample size in London, who completed questionnaires. Although the study methods were mainly quantitative and used statistical analysis, one study adopted a mixed methods approach. The results allowed the researchers to validate the scales, which demonstrated excellent internal consistency and adequate factorial and construct validity, in as much as both scales were unidimensional. The participants were categorized and the prevalence of problematic users was estimated. The cut-off points were satisfactorily tested for sensitivity, specificity and diagnostic accuracy, and the results demonstrated the presence of addictive behaviour in users of both technologies, where user profiles were also defined according to characteristics, patterns of use and addictive symptomatology. In conclusion, the thesis examined the border area between non-problematic and problematic Internet and mobile phone adolescent use, which international institutions like the American Psychiatric Association may begin to classify as mental disorders if the scientific and clinical evidence supports this.
La presente tesis doctoral se centra en la elaboración y adaptación de escalas psicométricas para evaluar el uso problemático de Internet (conocido como Problematic Internet Use o PIU) y del teléfono móvil (Problematic Mobile Phone Useo PMPU) en adolescentes barceloneses y londinenses. Se pretende diversos objetivos específicos: describir las características y patrones de uso de ambas tecnologías en estudiantes de secundaria, elaborar la Problematic Internet Entertainment Use Scale for Adolescents (PIEUSA) y adaptar la Mobile Phone Problematic Use Scale for Adolescents (MPPUSA)para ambas culturas, establecer las categorías de usuarios en ambas tecnologías y comprobar la precisión en la clasificación propuesta, así como proponer un modelo estadístico para obtener los factores predictivos y, por último, estimar la prevalencia de los adolescentes problemáticos de ambas tecnologías para poder estudiar su perfil psicosocial y tratar de abordar la sintomatología subyacente de carácter adictivo. Se realizan cinco estudios con metodología selectiva que se aplican a muestras por conveniencia de más de 1000 estudiantes de secundaria de cada país, en que se administra los cuestionarios. A pesar de que predominan métodos cuantitativos con análisis estadísticos, un estudio incluye metodología híbrida (mixed methods research). Los resultados principales permiten validar ambas escalas, que obtienen consistencia interna excelente y validez factorial y de constructo adecuadas, siendo unidimensionales. Se extraen las categorías de usuarios de ambas tecnologías, así como se estiman las prevalencias de los usuarios problemáticos. Asimismo, los puntos de corte extraídos de dicha clasificación se comprueban mediante la sensibilidad, especificidad y precisión global obteniendo resultados notables que garantizan su adecuación, así como demuestran la presencia de sintomatología adictiva en este tipo de adolescentes, cuyo perfil también se define según sus características y patrones de uso. En conclusión, se ha tratado de aportar luz a la frontera entre el uso problemático y no problemático de estas tecnologías en adolescentes, que organismos internacionales como la American Psychiatric Association empiezan a valorar como posible desorden mental si la evidencia científica y clínica lo demuestra.

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Kong, Tsz-wai Sally, e 江芷慧. "Business development of PCN operators in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31268870.

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Fang, Yuting. "A Case Study on How Chinese Students Use Their Cell Phones in Sweden Compared to That in China". Thesis, Växjö University, School of Mathematics and Systems Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-2271.

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This study focuses on cell phone usage. By comparing how a group of students use their cell phones in Sweden with that in China, alterant cell phone usage behaviors will be concluded. The study includes a case study. In order to do the research, the author selects a specific group and holds interviews. Three theories are used in this thesis which are: 1) mobile context, 2) switching behavior of mobile users and 3) transaction utility and reference situation. After introducing these three theories, the author concludes six theoretical factors which are combined into one competent framework. Base on the new framework, the author analyzes the result from the case study. After presenting the interview and the results, the author finds that Chinese students use their cell phones less frequent in Sweden compared to that in China. In order to find out the reasons, the author creates goal, emotion, fee, location and habit as the five matching factors which result in those changes. The matching factors are the bridge between the theories and the case study. After generalizing how those factors affect people while using cell phones, future work is to raise up some thoughts of how cell phones will be like in the future which is relevant to how to adapt information technology to human lives.

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Van, Schalkwyk Carlo. "Full state control of a Fury X-Cell unmanned helicopter". Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/2934.

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Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2009.
This thesis describes the successful development of an autopilot for an unmanned radio controlled helicopter. It presents a non-linear helicopter model. An adaptive linearised model is derived and used to design a controller. The adaptive full state controller is tested in various ways, including two aerobatic manoeuvres. A number of analyses are performed on the controller, including its robustness to parameter changes, noisy estimates, wind and processing power. The controller is compared with a non-adaptive counterpart, which leads to the conception, design and analysis of a much improved control structure. Practical flight test results are presented and analysed. In some instances available literature was reworked and re-derived to produce a genericmodel-controller package that can easily be adapted for helicopters of any make, model and size.

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Ribas, Arilson Sartorelli. "Telefone celular como um recurso didático: possibilidades para mediar práticas do ensino de física". Universidade Tecnológica Federal do Paraná, 2012. http://repositorio.utfpr.edu.br/jspui/handle/1/1236.

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Acompanha : Telefone celular: possibilidades de mediação pedagógica no espaço educativo
Na atualidade, existem diversos fatores que sugerem a necessidade de a escola rever as suas práticas de ensino: a rapidez com que as tecnologias de informação e comunicação – TIC – se alastram pela sociedade e, em especial, a utilização crescente do telefone celular por faixas etárias em idade escolar; o poder de convergência dessas TIC integrando recursos tecnológicos que podem ser utilizados como recursos didáticos; o fato de os estudantes atuais crescerem em um mundo tecnológico e apresentarem os seus padrões de pensamento funcionando de acordo com essa realidade; etc. Em contrapartida, observam-se: educadores, alheios à apropriação de TIC, apresentando, em muitos casos, resistência a elas; um descompasso entre como os sujeitos utilizam o celular, por exemplo, dentro e fora da escola; educadores, escolas, secretarias estaduais de educação posicionando-se contrários ao seu uso; projetos de lei e leis que regulamentam o seu uso no espaço educativo; etc. Por esses aspectos controversos investigou-se o uso do telefone celular como um recurso didático mediador em práticas do ensino de Física. Para tanto, desenvolveu-se uma pesquisa aplicada, com abordagem predominantemente qualitativa, de caráter exploratório quanto aos objetivos, e, participante quanto aos procedimentos técnicos adotados. Também foi utilizada a pesquisa documental e bibliográfica. Em seu desenvolvimento, inicialmente, via e-mail, foram coletados dados por meio de um questionário de múltipla escolha aplicados a professores de escolas particulares da Região Sul do Brasil, para identificar a realidade pesquisada e elaborar práticas de ensino possíveis de serem aplicadas na amostra estudada. As práticas construídas foram aplicadas em oficinas nas cidades de Ponta Grossa e Curitiba, estado do Paraná. Durante a aplicação, a coleta de dados ocorreu por meio de notas de campo do pesquisador, de gravação de sons e de um bate-papo ocorrido no msn messenger e de registros fotográficos. A análise dos dados foi realizada por triangulação. Os resultados mostraram a necessidade de se intensificarem cursos de formação continuada de professores e a produção de literatura nacional (artigos, dissertações, teses e livros) que explorem a temática do celular e suas funcionalidades em espaços educativos como recursos didáticos mediadores nas práticas do ensino de Física. Um livro foi organizado como produto final desta dissertação desenvolvida junto ao mestrado profissional do Programa de Pós-Graduação em Ensino de Ciência e Tecnologia da UTFPR, Campus Ponta Grossa–PR, estado do Paraná.
Currently, there are several factors that suggest the need for the school to review their teaching practices: 1) the speed with which information and communication technologies - ICT are spread throughout society and in particular the increasing use of mobile phone by groups in school age;2) the scope and power of integrating ICT convergence of these technological resources, that can be used as teaching resources; 3) the fact that nowadays students grow up in a technological world and make their thought patterns operating in accordance with this reality, etc... In contrast, there are educators unrelated to the appropriation of ICT, presenting, in many cases, resistance to them. There is a incongruity between how individuals use mobile phones, for example, inside and outside the school. There are also educators, schools, public educational departments claiming to be against mobile phones usage; bills and laws regulating their use in educational space, etc... For these controversial aspects we have investigated whether cell phone use as a teaching resource practices mediator in Physics teaching. For this purpose, we developed an applied research with qualitative and exploratory approach about the objectives, adopting participant and the technical procedures. A documental and bibliographical research was taken. First of all, data were collected by e-mail, through a multiple choice questionnaire applied to private school teachers in southern Brazil, to identify the researched reality and develop teaching practices likely to be applied in the studied corpus. Then, such practices were applied in workshops located in Curitiba and Ponta Grossa cities, in Paraná state. During the application, data was collected by the researcher's field notes. Then, we recorded chats about the workshops from an instant message software (msn messenger), and we took photographic records. Data analysis was performed by triangulation. The results showed the need to enhance continuing education courses for teachers and the production of national academic literature, such as articles, dissertations, theses and books that explore the theme of the cell phone and its functionality in educational spaces as an educational resource mediator in the practices of teaching Physics. A book as well was organized as a final product of this work developed by the Professional Master's Program from the Graduate School of Science and Technology (UTFPR), in Ponta Grossa Campus, in Paraná state.

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49

Patel, Chirag S. "Wireless channel modeling, simulation, and estimation". Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-03282006-200818/.

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Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2006.
Andrew, Alfred, Committee Member ; Durgin, Gregory, Committee Member ; Li, Geoffrey, Committee Member ; Ingram, Mary Ann, Committee Member ; Stuber, Gordon, Committee Chair.

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50

Olsson, Joel, e Junior Asante. "5G Simulation Framework". Thesis, Linköpings universitet, Kommunikationssystem, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-149484.

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Abstract (sommario):

From the first generation, 1G, to the fourth generation, 4G, the development and technological advancements in telecommunications network systems have been remarkable. Faster and better connections have opened up for new markets, ideas and possibilities, to that extent that there now is a demand that surpasses the supply. Despite all these advancements made in the mobile communications field most of the concept of how the technology works and its infrastructure has remained the same. This however, is about to change with the introduction of the fifth generation (5G) mobile communication. With the introduction of 5G much of the technology introduced will be different from that of previous generations. This change extends to include the entire infrastructure of the mobile communications system. With these major changes, many of the tools available today for telecommunications network evaluation do not really suffice to include the 5G network standard. For this reason, there is a need to develop a new kind of tool that will be able to include the changes brought by this new network standard. In this thesis a simulation framework adapted for the next generation telecommunication standard 5G is set to be developed. This framework should include many of the characteristics that set 5G aside from previous generations.

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Tesi sul tema "Cell phone systems Radio"

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