Zugl.: Wien, FH der Wirtschaft, Diplomarbeit

Packet communications have increasingly become popular since the launch of the first ever packet-switched network, the ARPANET. Evolution of such networks resulted in creation of the Internet, the global packet-switched network. Amongst the well-known advantages of packet-switching are service transparency, cost-effectiveness, and high system capacity. A natural pathway will incorporate tetherless mobility features to packet services. The key component to realisation of wireless packet communication is the multiple access technology (the subject of this thesis), capable of optimum sharing of scarce radio resources amongst a diverse set of packetized information sources. Based on core features of packet multiple access protocols, a classification is presented by which most proposed protocols could be mapped into. For mixed services, two equivalent offered loads, namely ''access load" and "traffic load", are derived. The former can be used for design, optimisation, and stabilisation of the access mechanism, whilst the latter is to evaluate the overall system performance. The proposed normalised offered loads are found accurate and instrumental in predicting and designing packet access protocols for mixed services. "Statistical upper-bounds" for packet access protocols are derived (both for random access and general access mechanisms), based on which an "efficiency factor" is defined to evaluate and compare merits of protocols against each other. Conventionally, analysis of resource-sharing systems with mixed services (such as multiple access protocols) involve multidimensional Markov chains which become quite intractable for more than two service types. In order to avoid multidimensional Markov analysis, an analytical method called "Aggregate Source Modelling" is proposed by means of which various service types are aggregated into a representative service type. The proposed method is deployed to analyse various queueing and multiple access scenarios. Finally, a series of multiple access protocols are presented for adapting real-time and non-real-time packet services to existing cellular and satellite systems. For evaluation purposes, the proposed statistical models of packet services (such as FTP, E- mail, WWW, packet voice, and so forth) are used throughout the thesis. These models have components of various statistical distributions, namely, Poisson (Exponential), lognormal, Pareto, Cauchy, Gaussian, Geometric, and Hyper-Exponential. Extensive discrete-time simulation models have been developed for evaluation purposes.

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Ciências da Saúde, 2008. / Submitted by Elna Araújo (elna@bce.unb.br) on 2011-06-07T12:58:39Z No. of bitstreams: 1 2008_SergioRodriguesAlves.pdf: 3973565 bytes, checksum: c46fd5703838994ec904a118a14f6a05 (MD5) / Approved for entry into archive by Patrícia Nunes da Silva(patricia@bce.unb.br) on 2011-06-14T16:54:54Z (GMT) No. of bitstreams: 1 2008_SergioRodriguesAlves.pdf: 3973565 bytes, checksum: c46fd5703838994ec904a118a14f6a05 (MD5) / Made available in DSpace on 2011-06-14T16:54:54Z (GMT). No. of bitstreams: 1 2008_SergioRodriguesAlves.pdf: 3973565 bytes, checksum: c46fd5703838994ec904a118a14f6a05 (MD5) / Este trabalho descreve a difusão de Remédios na Internet brasileira, considerando tal difusão enquanto agravos à saúde. Trata-se de um trabalho descritivo de cunho qualitativo que efetuou Análise de Conteúdo à Websites em idioma português. Para acercar-se do assunto e apresentá-lo em sua macro dimensão interliga áreas distintas: Tecnologia da Informação e Comunicação em Saúde, Comunicação Social, Ética e Bioética, Direito, Farmácia, Medicina, Comércio e Marketing Eletrônico, entre outras. Uma pergunta que pode nortear a leitura desta dissertação é: Já nos atentamos para a salvaguarda ou denúncia da difusão na Internet de práticas nocivas à saúde e, quiçá, ilícitas? Os resultados são apresentados em 12 (doze) categorias: 1-Apologias; 2- Práticas religiosas, simpatias ou humor; 3-Pseudo-associações; 4-Sigilo, segurança e logística facilitada; 5-Oferta em massa via e-mail; 6-Blogs e Anúncios; 7-Domínios Internacionais em Português Brasil; 8-Receitas / Remédios Caseiros; 9-Proposta de Cura com Alimentos; 10- Aquisições sem propósito de cura - mercado negro; 11-Informática para saúde do consumidor; 12-Outros. Sendo as categorias 1, 5 e 6 as mais recorrentes. Aponta-se que agravos à saúde que circulam na Internet brasileira, se apresentam de forma não explícita, dados os artifícios utilizados para “driblar” as autoridades e persuadir o internauta. O trabalho sugere uma maior discussão sobre à necessidade de: Qualidade das informações para educação do internauta consumidor; Estimular a regulação dos emissores de informação em saúde; Fortalecer o papel público institucional comprometido em avaliar informações e atos comerciais relacionados à saúde, estabelecendo sanções nos casos de nociva ou fraudulenta disseminação na Internet; Alertar ao internauta e acessoriamente ao poder público. ________________________________________________________________________________ ABSTRACT / This work if considers to describe the diffusion of Remedies in the Brazilian Internet, considering such diffusion while risks to the health. One is about a descriptive work of qualitative matrix that effected Analysis of Content to the Websites in Portuguese language. To present the subject in macro dimension, is made connection of distinct areas: Technology of the Information and Communication in Health, Social Communication, Ethics and Bioethics, Laws, Pharmacy, Medicine, Commerce and Electronic Marketing, etc. One asks that it can guide the reading of this dissertation is: Already we attempt against in them for safeguards or denunciation of the diffusion in the Internet of practical harmful to the health and, perhaps, illicit? The results are presented in 12 (twelve) categories: 1-Apologies; 2-Religious practical, popular beliefs or mood; 3-Pseudoassociations; 4-Secrecy, security and facilitated logistic; 5-Offer in mass by email; 6-Blogs and Announcements; 7-International domain in Brazilian Portuguese; 8-Prescriptions and homemade remedies; 9-Proposal of cure with foods; 10-Acquisition without cure intention - black market; 11-Computer science for health of the consumer; 12-Other. Being categories 1, 5 and 6 most recurrent. It is pointed that many of the risks to the health that circulate in the Brazilian Internet, if present of not explicit form, data the used artifices “to dribble” the authorities and to persuade the Internet user. The work suggests a bigger quarrel on a necessity of: Quality of the information for education of Internet user consuming; To stimulate the regulation of the senders of information in health; To fortify the engaged institucional public paper in evaluating information and commercial acts related to the health, establishing sanctions in the cases of harmful or fraudulent dissemination in the Internet; To alert to internauta and to the public power accessory.

Tesis para optar al grado de Magíster en Marketing / La publicidad online, específicamente las que son en formato de banners y contenido patrocinado generan diferentes reacciones en los usuarios web a nivel de entretenimiento, irritación, escepticismo e intención publicitaria. Ambos formatos tienen sus pros y contras, una ventaja del formato banner es el hecho de ser una publicidad prominente, por lo tanto es más fácil su reconocimiento, no así para el contenido patrocinado donde es más difícil identificar la intención publicitaria, sin embargo el formato banner genera respuestas más negativas por parte de los usuarios web al considerarla molesta, no así el contenido patrocinado dado que la publicidad del producto se encuentra inserto en el contenido editorial, entre otras ventajas y desventajas para uno y otro formato que se desarrollan en este estudio. Es por esto que basado en estudios relacionados a la publicidad se midieron las variables de valor percibido de la publicidad, las cuales incluye el valor de información, valor de entretención y valor de irritación. También se analizaron las variables de comprensión de la intención persuasiva y venta, el reconocimiento del formato y el escepticismo hacia la publicidad. En este estudio se experimenta con 2 productos, uno de alto y otro de bajo involucramiento con la finalidad de ver si hay diferencias en los resultados de las variables en estudio. Adicionalmente se analiza el efecto en las variables en los casos en que los participantes usan o no la marca. El experimento se montó en un sitio web de noticias altamente reconocido en Chile, los participantes fueron seleccionados de forma aleatoria a los diferentes tratamientos, donde debían observar los elementos de la página web asignada con atención, para luego contestar un cuestionario en forma online. Los resultados del estudio evidencian que el formato de banner genera mayor valor de irritación, es más reconocido el formato, se comprende mejor la intención persuasiva y venta y genera más escepticismo comparado al formato de contenido patrocinado tanto para el producto de alto y de bajo involucramiento. Por otro lado el contenido patrocinado genera mayor valor de información y valor de entretención comparado al formato banner (en ambos productos en estudio). La interacción entre los tratamientos y el uso de marca mostraron que quienes no usaban la marca el valor de entretención es menor para el formato de banner comparado con el formato de contenido patrocinado, en cambio para quienes si usaban la marca se observó mayor nivel de entretención en el formato banner comparado al contenido patrocinado.

Scholarly research is the sum of diverse activities and leads to the dissemination of a large amount of material. Traditional approaches to exploring and becoming proficient within an esoteric research field rely on slow and sometimes ineffective discourse, and depend more on a scholar's detective skill, effort, and perseverance. However, the Web has introduced the potential for improved accessibility, interconnectivity, and more efficient and effective communication; we are becoming e-Scholars. Current efforts on the Web have focussed mainly on improving the accessibility of on-line research material and as a result, researchers have yet to realise the full implications of the new medium. Consequently, the emphasis must shift to improving and enhancing access to scholarly material; this research proposes a novel approach by presenting researchers with the facility to comprehensively, extensively, and rationally explore their research field and ask intricate questions about it and the individual facts and issues raised by it. This is realised through the integration of principles from the hypertext, Semantic Web, and digital library fields to interconnect and analyse all scholarly material in the academic domain. The e-Scholar Knowledge Inference Model (ESKIMO) demonstrates the approach and provides a platform for evaluation and further research.

No description available.

The flourishing development of the Internet and network applications in communications, business, and entertainment, has resulted in resource allocation difficulties among a seemingly unlimited number of users and more complex charging rate determinations. As an important part of the global economy, some of the currently used Internet pricing schemes, such as flat rate charging, lack economic and network efficiency. Furthermore, many cross-disciplinary issues have yet to be resolved in the Internet Pricing research area. After an overview of the representative charging schemes, this work introduces a well defined structure for a complete and comprehensive understanding of Internet pricing schemes. Moreover, an evaluation cube representing eight different perspectives is proposed to examine charging schemes. Based on the evaluation results, classifications of the surveyed charging schemes from the economics and technology perspectives are presented. A new charging scheme is proposed that integrates the advantages of existing schemes. Distance, application type, and congestion are considered in the charging rate determination. The scheme is very flexible as an Internet Service Provider can adjust the priorities of the charging factors to satisfy its own objectives. The new scheme is analyzed and evaluated quantitatively and qualitatively. The results show the design objectives are met, and the scheme could be readily adopted by the Internet Service Providers.

Thesis (M.Dev) --University of Limpopo, 2011 / Internet services can make a significant contribution towards the development of people both in the urban and rural areas. The study is focused on the demand for internet services in the community of Nkowankowa in the Greater Tzaneen Municipality (GTM) in Limpopo province. Internet services bring multiple opportunities such as information, e-mails, games, shopping, banking, and real time news. The study examined the nature of demand for internet infrastructure and services in the area. The study further explored strategies that may be cost-effective and affordable to internet users and to recommend strategies through which the municipality can improve internet service delivery. The use of internet services was also examined (i.e., what are internet services needed for)? To understand these challenges and obtain in-depth information, both qualitative and quantitative research approach were used. The study population consisted of business owners (SMMEs), schoolmaster, students, and management in the municipal management committee, internet café owners, computer home users, police management and health management in Nkowakowa community in the Greater Tzaneen Municipality, selected through a purposive sampling method. These management workers are main role players in the use of internet services. A small sample of 40 respondents was selected based on the potential or likelihood that the respondents had same knowledge and interest in internet services. The researcher has selected the relative small sample because of the limited time frame. The findings reveal that Nkowankowa has a high shortage of internet infrastructure such as telephony. The entire Section C does not have a landline infrastructure and the only possibility is mobile connection, which is expensive. The internet cafés stand at 2 against the population of 30515 (Greater Tzaneen Municipality IDP: 2005-2006:12). The community depends on those two internet cafés. Learned individuals and business have afforded to connect. Others depend on internet services from their institutions, work place, and internet cafes. Challenges of the infrastructure unavailability such as telephony have a negative impact on utilization. It was recommended that the Municipality should partner with NGOs and community based organizations to deliver internet and related services to the community.

<p>This paper gives an account of a study regarding virtual communities, and tries to answer the question of which aspects that contribute towards the growth and success of a community. The purpose of the study has been twofold: to survey and identify factors that are important for the success of a virtual community; and to investigate whether there are differences in the views of success factors between leaders and members in a virtual community. The study is based upon a theoretical framework which gives a definition of the term virtual community, and how experts suggest these congregations are built. In the study is also included an extensive case study of two virtual communities. Finally, a discussion is made regarding the results of the study, and it is concluded that factors such as purpose, policies, trust, feedback and leaders are heavily contributing towards the success of virtual communities.</p>

Reproduction de : Thèse d' exercice : Médecine : Nancy 1 : 2002. / Thèse : 2002NAN11127. Titre provenant de l'écran-titre.