• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 14
  • 8
  • 4
  • 4
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 37
  • 37
  • 15
  • 14
  • 6
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 3
  • 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.
31

Service quality, customer satisfaction, switching cost en relación con el customer loyalty en la categoría de telefonía móvil en el Perú / Service quality, customer satisfaction, switching cost in relation to customer loyalty in the mobile services category in Peru

Alba Cuentas, María José, Salerno Malpartida, Bruno César 07 June 2021 (has links)
La alta demanda de servicios móviles, el aumento de operadoras en el mercado y su baja calidad de servicio, les ha dado motivos a los usuarios para migrar a otras operadoras al no estar conformes con el servicio brindado,no obstante no todos lo hacen. Por medio de una investigación cuantitativa a una muestra de 400 usuarios de servicios móviles, se estudiará el impacto del Service quality, customer satisfaction en el customer loyalty en la categoría de telefonía móvil en el Perú, colocando al switching cost como una variable moderadora. La falta de estudios sobre la industria de celulares en el Perú tomando el switching cost como variable moderadora es el principal motivo de esta investigación. / The high demand for mobile services, the increase in operators in the market and their low quality of service, have given users reasons to be able to migrate to other operators by not being satisfied with the one they present, however, not all do it. Through a quantitative study, the impact of Service quality, customer satisfaction on customer loyalty in the mobile telephony category in Peru is investigated, placing switching cost as a moderating variable. The lack of studies on the cell phone industry in Peru taking the switching cost as a moderating variable is the main reason for this research. / Trabajo de investigación
32

Law and Spatial Planning. Socio-Legal Perspectives on the Development of Wind Power and 3G Mobile Infrastructures in Sweden

Larsson, Stefan January 2014 (has links)
This PhD thesis in Spatial Planning argues for the importance of understanding the approaches to knowledge and rationalities embedded in spatially relevant decision-making. It emphasises the significance of seeing law as an empirical object of study for planning and environmental management. The Swedish development of wind power and 3G mobile infrastructures are used as cases to study these issues of principal interest. It is a compilation thesis consisting of a comprehensive introductory framework and five articles or chapters that have also been published elsewhere. The study is based on three main perspectives: Level of decision-making, legitimacy of different forms of knowledge involved in the process, and the sociolegal tension between formal law and its practical consequences. The thesis deals with problems stemming from the multi-level tensions in the planning and implementation that exist between the national, the regional and the local authorities. The legal context is analysed from the sociolegal perspective, in particular how the juridification of siting and permit conflicts determines what type of knowledge that can legitimately affect the decision-making and thereby set conditions for public participation. Finally, the thesis elaborates on the largely counterproductive results of the strong emphasis on “efficiency” in the revision of planning and permit processes for wind power and 3G-infrastructure, and what can be learnt from the experiences of the attempts at increasing efficiency. A combination of methods has been employed in the studies, and the data comes from a range of sources such as a large set of mast building permits, a sample of wind permit cases, as well as appealed permit cases. In addition, interviews have been conducted with judges from relevant courts, including regional handling officers who assess wind turbine applications. Legal documents such as preparatory work and licence conditions have also been analysed. The results show that there is a legal-rhetorical adaptation to the expert-based decision-making in court when permits are appealed. Further, the administrative levels interact poorly in the overall implementation. The national decisions, irrespective of the normative viewpoint of who should control the landscape planning, could be better informed of the preconditions at a local level that factually define the outcome of the implementation. The author, Stefan Larsson, holds a PhD in Sociology of Law, an LLM and is a sociolegal researcher who generally studies issues in the intersection of conceptual, sociolegal and technological change. The thesis has been supervised by Professor Lars Emmelin, The Swedish School of Planning, BTH, and co-supervised by Professor Karsten Åström, the Department of Sociology of Law, Lund University. The thesis is the result of research within the programme Tools for environmental assessment in strategic decision-making, MiSt, funded by The Swedish Environmental Protection Agency and the Centre for Work, Technology and Social Change at Lund University. / <p>Full text available: http://lup.lub.lu.se/luur/download?func=downloadFile&amp;recordOId=4587806&amp;fileOId=4 588973</p>
33

行動電話擴散研究之模型選用及驅動因子分析 / Model selection and driving forces for mobile telephony diffusion

朱文伶, Chu, Wen Lin Unknown Date (has links)
全球行動電話用戶數於2002年達到12億,首度超過固定電話用戶數之11億;行動電話用戶數並於2008年達41億,為固定電話用戶數(13億)之3倍以上。行動電話相對於固定電話之主要優勢在於系統之建置成本低及佈建速度快;行動電話之快速普及已成為創新擴散研究之重要題材。 行動電話擴散之研究為選取一成長模型(例如Gompertz、Logistic或Bass模型)並類比該模型以求出擴散之參數(例如成長速率),以進一步(1)了解相關驅動因子(例如技術創新、市場開放等)對擴散參數之影響,及(2)延伸擴散模型曲線以預測未來之成長。 惟成長模型之選取尚無原理原則可供遵循而具隨機性(ad hoc basis)。為找出模型選用之可能規律,以降低模型選用之隨機性並提高成長預測之準確度,本研究以十二個代表性國家(巴、中、法、德、印、日、韓、俄、星、台、英、美)至2007年之資料以比較三個最常用之成長模型之績效,即Gompertz、Logistic及Bass模型。模型績效逐年比較標準係採用rmse值,並輔以Friedman test檢測模型績效差異之顯著性,再對照模型之機制意涵,以進一步了解最適模型之選用原則。 此外,台灣行動電話普及率於2002年為108%居全球之冠,而中國自2001年起取代美國成為全球具最多行動電話用戶數之單一國家,台灣及中國屬行動電話擴散之重要個案,惟目前尚缺此二個案之實證研究。為補足此一缺口,本研究亦對台灣及中國行動電話擴散之驅動因子進行實證研究,以進一步了解擴散之關鍵驅動力。 研究發現由於目前統計軟體之進步,Gompertz、Logistic及Bass三模型均可獲致極佳之匹配度而難分軒輊,惟模型預測力(延伸曲線)則具差異性。12個模型選用樣本國家中之8個國家(巴、中、法、德、日、韓、英、美)係以Gompertz模型具較佳之預測力;依Gompertz模型機制意涵,代表行動電話擴散早期係受網路外部性(口耳相傳)影響,惟至擴散後期(例如過了擴散極大值之一半)則已不相關。此外,若因市場開放等重大變因造成行動電話之快速擴散,則Logistic模型具有較佳之績效,如台灣及俄羅斯屬之。依Logistic模型機制意涵,代表擴散係受網路外部性所影響。Bass模型應用於行動電擴散時,因該模型所算出之創新係數偏低,績效與Logistic模型相近,而Logistic模型為Bass模型之創新係數為0時之特例。 台灣及中國行動電話擴散之驅動因子研究發現(1)價格下降及(2)預付卡之推行對加速擴散具顯著性,兩者均對低階市場之採用具影響力。鑑於高階市場將先飽和,爰未來加速行動電話擴散之關鍵驅動因子應係與推動低階市場採用具密切相關性。以中國為例,未來市場開放競爭造成價格再度大幅下降,將進一步促低階市場採用,加速中國行動電話之普及。 / The number of mobile telephone subscriptions reached 1.2 billion globally in 2002, exceeding fixed-line telephony subscriptions (1.1 billion) for the first time. The number of mobile telephone subscriptions reached 4.1 billion globally in 2008, over three times the number of fixed-line telephone subscriptions (1.3 billion). The main advantages of mobile telephony over fixed-line are low cost and rapid facility deployment. The rapid diffusion of mobile telephony has become an important topic in innovation diffusion. The conventional approach to studying mobile telephony diffusion is to analogize a single growth model, such as the Gompertz, Logistic or Bass model, and calculate the model parameters, for example growth rate. The significance of certain selected driving forces, such as technology innovation or market competition, to the studied parameters, such as growth rate, is then estimated. The diffusion growth can also be forecast by extrapolating the diffusion curve. Utilizing the growth model analogy is the first step in analyzing mobile telephony diffusion. However, no principles or rules exit for selecting a growth model. To identify rules for model selection to reduce randomness and increase forecast accuracy, this work uses 12 sample countries, namely Brazil, China, France, Germany, India, Japan, Korea, Russia, Singapore, Taiwan, the UK and the USA, employing data prior to 2008 to compare the performance of three most commonly used models, namely the Gompertz, Logistic and Bass models. The root mean square error (rmse) is chosen as the criterion for measuring annual model performance. The work uses the Friedman test to examine the significance of differences in performance between models. The implications of model mechanisms are emphasized to investigate the selection rule for the most appropriate model. The penetration of mobile telephony in Taiwan was 108% in 2002, ranking first in the world. Furthermore, in 2001 the number of mobile telephony in China replaced the United States as number one in the world. Both Taiwan and China are important examples for mobile telephony diffusion. However, no empirical investigation has been performed in these two cases. To fill this gap, this work estimated the driving forces for mobile telephony diffusion in Taiwan and China to learn about the critical drivers of the mobile telephony diffusion. Empirical results indicate that due to improvements in statistical software, providing good fitness for all three models, namely the Gompertz, Logistic and Bass models, distinguishing which has the best fitness is difficult. However, the performance of the three models is distinguishable when forecasting based on extrapolating the diffusion curve. In eight of the 12 examples, namely Brazil, China, France, Germany, Japan, Korea, the UK and the USA, the Gompertz model is the most appropriate model for forecasting. The mechanism of the Gompertz model means that during the initial stage the diffusion is correlated with network externalities (namely word of mouth), however, this correlation reduces during the later stages (such as pass one half of the maximum potential). Moreover, the cases of Taiwan and Russia demonstrated that the Logistic model performs well provided some significant driver of the diffusion exists. The mechanism of the Logistic model means that the diffusion is correlated with network externalities throughout the whole diffusion. Furthermore, using Chinese data, when the Bass model is applied, because of its low innovation coefficient, it performs similarly to the Logistic model, which is a special case of the Bass model in which the innovation coefficient equals zero. Empirical results for the critical driving forces of mobile telephony diffusion in Taiwan and China indicate that (1) reducing prices and (2) the launch of pre-paid services are crucial to mobile telephony diffusion. Both factors are essential to mobile telephony adoption in low-end markets. The high-end market is the first to be saturated by mobile telephony adoption, future drivers of the mobile telephony diffusion should be highly correlated with low-end market demand. Taking China as an example, the opening of the market to further reduce tariffs will attract mobile telephony adoption in the low-end market, facilitating the mobile telephony diffusion.
34

Avalia??o dos modelos de predi??o de propaga??o para telefonia m?vel celular na cidade do Natal

Pinheiro, Fred Sizenando Rossiter 17 February 2006 (has links)
Made available in DSpace on 2014-12-17T14:55:48Z (GMT). No. of bitstreams: 1 FredSRP.pdf: 1871145 bytes, checksum: 9d94e1a0030a3d2f8d2aa6aaa2df93bd (MD5) Previous issue date: 2006-02-17 / The development of wireless telecommunication in the last years has been great. It has been taking academics to conceive new ideas and techniques. Their aims are to increase the capacity and the quality of the system s services. Cells that are smaller every time, frequencies that are every time higher and environments that get more and more complex, all those facts deserve more accurate models the propagation prediction techniques are inserted in this context and results with a merger of error that is compatible with the next generations of communication systems. The objective of this Work is to present results of a propagation measurement campaign, aiming at pointing the characteristics of the mobile systems covering in the city of Natal (state of Rio Grande do Norte, Brazil). A mobile laboratory was set up, using the infra-structure available and frequently used by ANATEL. The measures were taken in three different areas: one characterized by high buildings, high relief, presence of trees and towers of different highs. These areas covered the city s central zone, a suburban / rural zone and a section of coast surrounded by sand dunes. It is important to highlight that the analysis was made taking into consideration the actual reality of cellular systems with covering ranges by reduced cells, with the intent of causing greater re-use of frequencies and greater capacity of telephone traffic. The predominance of telephone traffic by cell in the city of Natal occurs within a range inferior to 3 (three) km from the Radio-Base Station. The frequency band used was 800 MHz, corresponding to the control channels of the respective sites, which adopt the FSK modulation technique. This Dissertation starts by presenting a general vision of the models used for predicting propagation. Then, there is a description of the methodology used in the measuring, which were done using the same channels of control of the cellular system. The results obtained were compared with many existing prediction models, and some adaptations were developed by using regression techniques trying to obtain the most optimized solutions. Furthermore, according to regulations from the old Brazilian Holding Telebr?s, a minimum covering of 90% of a determined previously area, in 90% of the time, must be obeyed when implanting cellular systems. For such value to be reached, considerations and studies involving the specific environment that is being covered are important. The objective of this work is contribute to this aspect / O enorme desenvolvimento das comunica??es sem fio tem levado estudiosos a conceber novas id?ias e t?cnicas visando aumentar a capacidade e melhorar a qualidade de servi?o dos sistemas de comunica??o m?vel. C?lulas cada vez menores, freq??ncias cada vez mais altas e ambientes cada vez mais complexos est?o a merecer modelamentos mais acurados e as t?cnicas de predi??o de propaga??o se inserem neste contexto, estando ainda a merecer resultados com margem de erro compat?vel com as pr?ximas gera??es de sistemas de comunica??o. Este trabalho tem por finalidade apresentar os resultados de uma campanha de medidas de propaga??o visando caracterizar a cobertura de sistemas m?veis celulares na cidade do Natal, RN. Um laborat?rio m?vel foi montado aproveitando a estrutura dispon?vel e utilizada rotineiramente pela ANATEL. As medi??es foram efetuadas em ?reas com caracter?sticas de edifica??es, relevo, arboriza??o e alturas de torres diversificadas, abrangendo a zona central da cidade, uma zona de caracter?stica suburbana / rural e trecho litor?neo circundado por dunas. ? importante destacar que a an?lise foi feita considerando a realidade atual dos sistemas celulares com raios de cobertura por c?lula reduzidos visando proporcionar maior reuso de freq??ncias e maior capacidade de tr?fego telef?nico. A predomin?ncia do tr?fego telef?nico por c?lula na cidade do Natal ocorre dentro de um raio inferior a 3 (tr?s) km em rela??o a Esta??o R?dio-Base. A faixa de freq??ncia utilizada foi de 800 MHz, correspondendo aos canais de controle dos respectivos sites, os quais adotam a t?cnica de modula??o FSK. Neste trabalho, apresenta-se inicialmente uma vis?o geral dos modelos utilizados para predi??o de propaga??o. Em seguida, descreve-se a metodologia utilizada nas medi??es, as quais foram efetuadas aproveitando os pr?prios canais de controle do sistema celular. Os resultados obtidos foram comparados com diversos modelos de predi??o existentes e foram desenvolvidas adapta??es utilizando t?cnicas de regress?o na tentativa de obten??o de solu??es mais otimizadas. Al?m disso, ? importante observar que, de acordo com norma da antiga holding brasileira Telebr?s, uma cobertura m?nima de 90% de uma ?rea pr?-estabelecida em 90% do tempo deve ser obedecida em implanta??es de sistemas celulares. Para que tal ?ndice seja obtido, considera??es e estudos envolvendo o ambiente espec?fico de atendimento s?o importantes. Este trabalho apresenta uma contribui??o nesse sentido
35

Diseño de una red de acceso de tecnología 5G que posibilite el patrullaje mediante drones en el distrito de San Borja / Design of a 5G technology access network that enables drone patrolling in the San Borja district

Documet Celis, Carlos Andres 24 April 2021 (has links)
En este trabajo se ha diseñado una red de comunicaciones móvil 5G escalable que permita la recepción de imágenes provenientes de drones desplegados remotamente a lo largo del distrito de San Borja todo esto en concordancia con las normativas y estándares vigentes de la 3GPP, la cual está orientada a optimizar las herramientas de video vigilancia de la Municipalidad de San Borja, proponiendo una solución mediante dispositivos que permitan detectar actos delictivos mediante una plataforma de comunicación móvil de alta velocidad la cual hará uso de la infraestructura de red que ya se encuentra desplegada en el distrito. / In this work, a scalable 5G mobile communications network has been designed that allows the reception of images from drones deployed remotely throughout the San Borja district, all of this in accordance with the current regulations and standards of the 3GPP, which is oriented to optimize the video surveillance tools of the Municipality of San Borja, proposing a solution through devices that allow detecting criminal acts through a high-speed mobile communication platform which will make use of the network infrastructure that is already deployed in the district. / Tesis
36

Closing of 3G Sites : Model for Decision Making

Chaudron, Emmanuel January 2018 (has links)
Radio access technologies evolving fast, mobile operators have to handle an increasing amount of base stations and frequency bands for their network to continue to function. This is a costly venture for mobile network operators that continuously have to keep up to date with never-ending advancements in technologies, as base stations are costly to build and to maintain. It is therefore necessary for these companies to investigate when to close down base stations that are not necessary anymore. With the upcoming release of 5G, it is expected that 3G is going to be less and less used—as of 2018, it is already less used than 4G in developed countries.This thesis analyses the corporate data of a mobile operator, Telenor Sweden, in order to make clear which metrics are important to take into account as regards to deciding whether or not to close down a base station. It provides methods and models to help a mobile operator to take such a decision. It focuses on UMTS (3G) base stations, even though the results can be generalized for other technologies as well.It evaluates the economic feasibility of closing a base station, with regards to how many users are still connecting to it. More importantly, it explains for what reasons users’ devices switch to 3G, and investigates what can be done to avoid switching from 4G to 3G, so as to make it easier to close down a 3G site. It provides eventually a model to help to know when closing a site, given the traffic data of the operator. / Radioåtkomstteknologier utvecklas snabbt, mobiloperatörer måste hantera en ökande mängd basstationer och frekvensband för att deras nätverk fortsätter att fungera. Detta är ett dyrt satsning för mobilnätoperatörer som kontinuerligt måste hålla sig uppdaterade med oändliga tekniska framsteg, eftersom basstationerna är kostsamma att bygga och underhålla. Det är därför nödvändigt för dessa företag att undersöka när man ska stänga basstationer som inte längre är nödvändiga. Med den kommande utgåvan av 5G förväntas 3G att bli mindre och mindre används. Från och med 2018 används den redan mindre än 4G i industriländer. Denna avhandling analyserar företagsdata från en mobiloperatör, Telenor, för att klargöra vilka mätvärden som är viktiga att ta hänsyn till när det gäller att avgöra om en basstation ska stängas eller inte. Det ger metoder och modeller för att hjälpa en mobiloperatör att fatta ett sådant beslut. Den fokuserar på UMTS (3G) basstationer, även om resultaten kan generaliseras för annan teknik också. Det utvärderar den ekonomiska möjligheten att stänga en basstation, med tanke på hur många användare som fortfarande ansluter till den. Viktigare är det att det förklaras av vilka anledningar användarens enheter växlar till 3G och undersöker vad som kan göras för att undvika att växla från 4G till 3G, så att det blir lättare att stänga en 3G-basstation. Det ger så småningom en modell som hjälper till att veta när man stänger en webbplats, med tanke på operatörens trafikdata.
37

Mandos: Um método de Interação com o usuário em Aplicativos Embarcados na Telefonia Móvel / Mandos: An Interaction Method with the User in Embedded Application in the Mobile Telephony

Teófilo, Mauro Ricardo da Silva 21 September 2007 (has links)
Made available in DSpace on 2015-04-11T14:02:54Z (GMT). No. of bitstreams: 1 Mauro Ricardo da Silva Teofilo.pdf: 1416910 bytes, checksum: d4f41b9f784e48975a66441e08b837f1 (MD5) Previous issue date: 2007-09-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / With the intense use of applicative in mobile device, the question usability begins to invigorate strongly as a study object, it is being considered a determinant factor of the success of this segment of the mobile computation. This work proposes an improvement way in the usability of the embedded applicative in mobile devices, considering a new method of user interaction. The Mandos interaction method is based on task idea, which consists in a possible operation that could be executed in an applicative by the user and probabilities between task changes. The cited probabilities will be used for construction of the user interface to interact dynamically with the user. To validate the considered method was developed a framework, called Mandos, which propitiates functionalities to the applicative developer that uses Java technology. A case study will be presented where some prototypes of embedded applicative mobile was developed, using Mandos framework for the interaction method evaluation. The evaluation was established in order to identify any relation of usability gain or loss of applicatives, having like approvers the own users of the embedded applicative in mobile telephones. / Com o uso intenso de aplicativos em aparelho celulares a questão da usabilidade passa a vigorar fortemente como objeto de estudo, sendo considerado um fator determinante do sucesso deste segmento da computação móvel. Este trabalho propõe uma forma de aprimoramento da usabilidade dos aplicativos embarcados em aparelhos celulares, formulando um novo método de interação com o usuário. O método de interação Mandos foi baseado na idéia de tarefas, que consiste em uma operação de uma função de um aplicativo a ser executada pelo usuário, e nas probabilidades de transição entre tarefas. As probabilidades de transição entre tarefas serão utilizadas para construção da interface com o usuário, e tais probabilidades são alteradas no decorrer do uso do aplicativo, fazendo com que a interação seja dinâmica. Para validar o método proposto foi desenvolvido um framework, chamado de Mandos, que adiciona algumas funcionalidades já prontas para o desenvolvedor de aplicativos que utiliza a tecnologia Java. Será apresentado um estudo de caso onde alguns protótipos de aplicativos embarcados em telefone móveis foram desenvolvidos, usando o framework Mandos, para a avaliação do método de interação. A avaliação foi baseada de modo a identificar qualquer relação de ganho ou perda de usabilidade dos aplicativos, tendo com avaliador os próprios usuários dos aplicativos embarcados em telefones móveis.

Page generated in 0.4503 seconds