Are decision-makers, and public ones in particular, considering the spatial characteristics of territories when they are making decisions? Which elements should be included in computer-based systems supporting such decisions? These two questions summarise the issues geographic information system scientists are addressing. They also constitute the starting point of this investigation on the theme of errors and uncertainty in spatial decision support systems. While decision theories, methodologies and techniques abound, none are peculiar to spatial issues. At best, they are using spatial data and in a few cases they are applied to helping solve spatial problems. It has been recognised that spatial data need distinct management systems. Should it be the same for spatial decisions? By postulating that spatial decision is a specific field requiring its own treatise, this author initiates an original reflexion. Following a holistic approach, this theoretical work develops a conceptual decision model: the 'decisional fountain'. This model gives a coherent and integrated view on the various fields of decision-making. Based on the postulate and on the model developed, several theories and techniques are revisited in a truly spatial perspective. The ontology of spatial decision has been enriched by a variety of experiences. Dealing with drought at the European level, allocating water resources from the field scale to the country scale, regional spatial planning, performing strategic environmental assessment, conceptualising the parking of a vehicle, developing the spatial abilities of children, all have fed this conceptual research. Some of them are illustrating this manuscript. Taking a spatial information science perspective, this manuscript leads you towards a 'spatial decision' theory.

The aim of this undergraduate thesis was to study what the participation in the activities of the Fontain House in Stockholm means to its members. The research questions dealt with how the members describe their participation in the activities, whether they say that it has helped them, and, in that case, in which way. Furthermore, they dealt with how the members argue about their experiences of mental illness and of social help. The study was carried out within the framework of the narrative method. As tools for analyzing the narratives, parts of An-tonovsky’s theories as well as the theoretical concepts of inclusion and exclusion as described by Madsen, were used. Furthermore, earlier research on the Fontain House was applied in the analysis. The results of the study showed that all of the respondents said that the Fontain House was of great importance in their lives and that they could participate in its activities in regard to their own needs and resources. The thesis discusses whether the selection and the execution of the study may have affected the results toward a positive tendency. Concerning how the re-spondents argue about mental illness and about social help, the answers varied strongly.

Scalable on-demand content delivery systems, designed to effectively handle increasing request rates, typically use service aggregation or content replication techniques. Service aggregation relies on one-to-many communication techniques, such as multicast, to efficiently deliver content from a single sender to multiple receivers. With replication, multiple geographically distributed replicas of the service or content share the load of processing client requests and enable delivery from a nearby server.<p>Previous scalable protocols for downloading large, popular files from a single server include batching and cyclic multicast. Analytic lower bounds developed in this thesis show that neither of these protocols consistently yields performance close to optimal. New hybrid protocols are proposed that achieve within 20% of the optimal delay in homogeneous systems, as well as within 25% of the optimal maximum client delay in all heterogeneous scenarios considered.<p>In systems utilizing both service aggregation and replication, well-designed policies determining which replica serves each request must balance the objectives of achieving high locality of service, and high efficiency of service aggregation. By comparing classes of policies, using both analysis and simulations, this thesis shows that there are significant performance advantages in using current system state information (rather than only proximities and average loads) and in deferring selection decisions when possible. Most of these performance gains can be achieved using only local (rather than global) request information.<p>Finally, this thesis proposes adaptations of already proposed peer-assisted download techniques to support a streaming (rather than download) service, enabling playback to begin well before the entire media file is received. These protocols split each file into pieces, which can be downloaded from multiple sources, including other clients downloading the same file. Using simulations, a candidate protocol is presented and evaluated. The protocol includes both a piece selection technique that effectively mediates the conflict between achieving high piece diversity and the in-order requirements of media file playback, as well as a simple on-line rule for deciding when playback can safely commence.

Scalable on-demand content delivery systems, designed to effectively handle increasing request rates, typically use service aggregation or content replication techniques. Service aggregation relies on one-to-many communication techniques, such as multicast, to efficiently deliver content from a single sender to multiple receivers. With replication, multiple geographically distributed replicas of the service or content share the load of processing client requests and enable delivery from a nearby server.<p>Previous scalable protocols for downloading large, popular files from a single server include batching and cyclic multicast. Analytic lower bounds developed in this thesis show that neither of these protocols consistently yields performance close to optimal. New hybrid protocols are proposed that achieve within 20% of the optimal delay in homogeneous systems, as well as within 25% of the optimal maximum client delay in all heterogeneous scenarios considered.<p>In systems utilizing both service aggregation and replication, well-designed policies determining which replica serves each request must balance the objectives of achieving high locality of service, and high efficiency of service aggregation. By comparing classes of policies, using both analysis and simulations, this thesis shows that there are significant performance advantages in using current system state information (rather than only proximities and average loads) and in deferring selection decisions when possible. Most of these performance gains can be achieved using only local (rather than global) request information.<p>Finally, this thesis proposes adaptations of already proposed peer-assisted download techniques to support a streaming (rather than download) service, enabling playback to begin well before the entire media file is received. These protocols split each file into pieces, which can be downloaded from multiple sources, including other clients downloading the same file. Using simulations, a candidate protocol is presented and evaluated. The protocol includes both a piece selection technique that effectively mediates the conflict between achieving high piece diversity and the in-order requirements of media file playback, as well as a simple on-line rule for deciding when playback can safely commence.

Fountain codes have demonstrated great results for the binary erasure channel and have already been incorporated into several international standards to recover lost packets at the application layer. These include multimedia broadcast/multicast sessions and digital video broadcasting on global internet-protocol. The rateless property of Fountain codes holds great promise for noisy channels. These are more sophisticated mathematical models representing errors on communications links rather than only erasures. The practical implementation of Fountain codes for these channels, however, is hampered by high decoding cost and delay. In this work we study trapping sets in Fountain codes over noisy channels and their effect on the decoding process. While trapping sets have received much attention for low-density parity-check (LDPC) codes, to our knowledge they have never been fully explored for Fountain codes. Our study takes into account the different code structure and the dynamic nature of Fountain codes. We show that 'error-free' trapping sets exist for Fountain codes. When the decoder is caught in an error-free trapping set it actually has the correct message estimate, but is unable to detect this is the case. Thus, the decoding process continues, increasing the decoding cost and delay for naught. The decoding process for rateless codes consists of one or more decoding attempts. We show that trapping sets may reappear as part of other trapping sets on subsequent decoding attempts or be defeated by the reception of more symbols. Based on our observations we propose early termination methods that use trapping set detection to obtain improvements in realized rate, latency, and decoding cost for Fountain codes. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2009-10-29 14:33:06.548

Este estudo identifica os fatores relacionados aos deslocamentos espaciais do Chafariz Imperador. Trata-se de um monumento instalado no final de 1866 e início de 1867, na Praça da Matriz em Porto Alegre (RS), pela Companhia Hidráulica Porto Alegrense, em virtude da comemoração do início do fornecimento de água potável aos cidadãos da Capital. Atualmente, algumas peças que restaram dele encontram-se na Praça Dom Sebastião, localizada no centro da cidade. A reconstrução da trajetória histórica do monumento entre o período de 1866-2013 deu-se a partir de uma pesquisa documental de caráter qualitativo nos seguintes locais: Arquivo Histórico de Porto Alegre Moysés Vellinho, Arquivo Histórico do Rio Grande do Sul, Museu da Comunicação Hipólito José da Costa, Museu Joaquim José Felizardo. Além desses, nos acervos digitais da Fundação Biblioteca Nacional e Center Research for Libraries. Ao final deste estudo, identifiquei que as relações entre os deslocamentos espaciais do Chafariz Imperador e as transformações da paisagem urbana de Porto Alegre, estão associadas à Cultura Política dos grupos detentores do poder. Verifiquei que apenas, mais recentemente, as decisões quanto à localização e à preservação do monumento passam a ser tratadas por agentes públicos especializados que se ocupam do Patrimônio Cultural da cidade. / This study identifies factors related to geographical displacements of the Emperor Fountain. It is a monument installed in the late 1866 and in the beginning of 1867, in Matriz square in Porto Alegre (RS), the Porto Alegrense Hydraulic Company due to the celebration of the start of the drinking water supply to Porto Alegre´s citizens. Nowadays, some remaining parts of the fountain are located in Dom Sebastião square, in the city´s downtown. The rebuilding of the historical trajectory of the monument between the periods of 1866-2013 took place from a documental research of qualitative focus in the following places: Vellinho Moyses Historical Archive of Porto Alegre, Historical Archive of Rio Grande do Sul state, Hippolytus José da Costa Museum of Communication, Joaquim José Felizardo Museum. In addition to these places, in the digital collections of the National Library Foundation and in the Center Research for Libraries. At the end of this study, I identified relationships between spatial displacements of the Emperor Fountain and the changes of Porto Alegre´s urban landscape, which are connected to the Political Culture of the most powerful and influent groups of the city. I also noticed that only recently, the decisions regarding the location and preservation of the monument began to be treated by specialized public officials dealing with the city´s cultural heritage.

Made available in DSpace on 2016-08-03T12:18:47Z (GMT). No. of bitstreams: 1 Marco Aurelio de Brito.pdf: 763965 bytes, checksum: c00f02cab72b7d5400f59d0b1c257925 (MD5) Previous issue date: 2011-08-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Esta pesquisa se propõe a compreender qual o significado do ministério feminino e as mútuas relações dos símbolos na comunidade joanina. O filtro teológico adotado para essa compreensão partiu como base de João 4, em que surgem, dentro dessa perícope, sinais de uma comunidade em um processo teológico em diversas fases. É relevante a exegese porque nos permite entender o contexto histórico, as dificuldades da comunidade joanina e quais as principais questões discutidas dentro desse texto. A intenção primária é apresentar o valor da mulher para a comunidade de João em contrapartida com a opressão religiosa no mesmo período. Partindo do texto de Jo 4, 4-42, pretendemos também entender a proposta do redator, que usa os símbolos como forma de linguagem para classificar os personagens, a qualidade da missão e a forma de servir ao reino de Deus na perspectiva joanina.

[pt] Há, nos dias atuais, uma crescente demanda pelo transporte de video sobre IP, i.e., para distribuição de conteúdo pela Internet, por serviços de IPTV em definição padrão e em alta definição e, mesmo para uso interno nas redes de emissoras tradicionais de televisão, que transportam contribuições de elevada qualidade para seus programas. Em tais aplicações, o conteúdo dos programas é transportado usando MPEG-2 ou MPEG-4, sob a forma de MPEG-2 Transport Streams, encapsulados com protocolos tais como RTP, UDP e IP. As redes IP, que são modelizadas como Redes com Apagamento de Pacotes (PEC) não foram, no entanto, concebidas para o transporte de mídias em tempo real, esbarra portanto em problemas comuns como perdas de pacotes e jitter, gerando perturbações que se refletem na recepção do conteúdo. Os métodos tradicionais para superar estas dificuldades, como por exemplo, os que se baseiam em retransmissões usando protocolos ARQ (Automatic Repeat on Request), não são uma solução eficiente para proteger a transmissão de multimídia em tempo real. A proteção de multimídia transmitida em tempo real via IP recorre, neste caso, aos códigos para canal. Há códigos para canal recomendados em RFC s e Padrões, usados amplamente pelos fabricantes de equipamento. Os modernos Códigos Fontanais, possuem características atraentes para o transporte de conteúdos multimídia em tempo real. Neste trabalho, simulações são realizadas, onde o conteúdo encapsulado em Transport Stream, é protegido com Códigos Fontanais antes do encapsulamento para o envio através da rede. A título de comparação, o experimento é realizado também usando outros códigos para canal recomendados. Para realizar a comparação são usadas medições padronizadas do Transport Stream, medições objetivas como artefatos de blocagem e finalmente uma análise subjetiva do conteúdo recebido é usada. O trabalho conclui com a proposta de um Codificador de canal adaptável para Transport Stream. / [en] There is a growing demand for the transport of video over IP today, i.e., for content distribution over the Internet, IPTV services in Standard and High Definition, or even inside traditional broadcasters networks, transporting broadcast quality contributions to the main program. In such applications, the source encoded MPEG-2 or -4 content is transported in the form of MPEG-2 Transport Streams, encapsulated over network protocols. However, IP networks, which can be modeled as Packet Erasure Networks (PEC), were not originally designed for the transport of real time media. There are problems, such as packet drops and jitter, which generate severe impairments in the content that is decoded at the reception. Traditional methods for overcoming these problems, as for example retransmissions performed by Automatic Repeat Request (ARQ) protocols, are not suitable for real-time multimedia protection. Channel coding is the solution of choice for protecting real-time multimedia over IP. There are channel coding schemes specified in open recommendations and Standards, widely adopted by equipment vendors today. Fountain Codes present very attractive characteristics for the transport of real-time multimedia. In the present work, simulations with a Fountain code, protecting Transport Stream contents prior to network encapsulation, are presented. The experiment if repeated with other channel coding techniques commonly employed today. In order to analyze the decoded contents and obtain comparative results, standardized Transport Stream measurements, objective Blocking Artifacts measurements and subjective analysis of the decoded samples are employed. This work is concluded with the proposal of a Transport Stream Adaptive channel encoder, that is explained in Appendix-B.

Este estudo identifica os fatores relacionados aos deslocamentos espaciais do Chafariz Imperador. Trata-se de um monumento instalado no final de 1866 e início de 1867, na Praça da Matriz em Porto Alegre (RS), pela Companhia Hidráulica Porto Alegrense, em virtude da comemoração do início do fornecimento de água potável aos cidadãos da Capital. Atualmente, algumas peças que restaram dele encontram-se na Praça Dom Sebastião, localizada no centro da cidade. A reconstrução da trajetória histórica do monumento entre o período de 1866-2013 deu-se a partir de uma pesquisa documental de caráter qualitativo nos seguintes locais: Arquivo Histórico de Porto Alegre Moysés Vellinho, Arquivo Histórico do Rio Grande do Sul, Museu da Comunicação Hipólito José da Costa, Museu Joaquim José Felizardo. Além desses, nos acervos digitais da Fundação Biblioteca Nacional e Center Research for Libraries. Ao final deste estudo, identifiquei que as relações entre os deslocamentos espaciais do Chafariz Imperador e as transformações da paisagem urbana de Porto Alegre, estão associadas à Cultura Política dos grupos detentores do poder. Verifiquei que apenas, mais recentemente, as decisões quanto à localização e à preservação do monumento passam a ser tratadas por agentes públicos especializados que se ocupam do Patrimônio Cultural da cidade. / This study identifies factors related to geographical displacements of the Emperor Fountain. It is a monument installed in the late 1866 and in the beginning of 1867, in Matriz square in Porto Alegre (RS), the Porto Alegrense Hydraulic Company due to the celebration of the start of the drinking water supply to Porto Alegre´s citizens. Nowadays, some remaining parts of the fountain are located in Dom Sebastião square, in the city´s downtown. The rebuilding of the historical trajectory of the monument between the periods of 1866-2013 took place from a documental research of qualitative focus in the following places: Vellinho Moyses Historical Archive of Porto Alegre, Historical Archive of Rio Grande do Sul state, Hippolytus José da Costa Museum of Communication, Joaquim José Felizardo Museum. In addition to these places, in the digital collections of the National Library Foundation and in the Center Research for Libraries. At the end of this study, I identified relationships between spatial displacements of the Emperor Fountain and the changes of Porto Alegre´s urban landscape, which are connected to the Political Culture of the most powerful and influent groups of the city. I also noticed that only recently, the decisions regarding the location and preservation of the monument began to be treated by specialized public officials dealing with the city´s cultural heritage.

Este estudo identifica os fatores relacionados aos deslocamentos espaciais do Chafariz Imperador. Trata-se de um monumento instalado no final de 1866 e início de 1867, na Praça da Matriz em Porto Alegre (RS), pela Companhia Hidráulica Porto Alegrense, em virtude da comemoração do início do fornecimento de água potável aos cidadãos da Capital. Atualmente, algumas peças que restaram dele encontram-se na Praça Dom Sebastião, localizada no centro da cidade. A reconstrução da trajetória histórica do monumento entre o período de 1866-2013 deu-se a partir de uma pesquisa documental de caráter qualitativo nos seguintes locais: Arquivo Histórico de Porto Alegre Moysés Vellinho, Arquivo Histórico do Rio Grande do Sul, Museu da Comunicação Hipólito José da Costa, Museu Joaquim José Felizardo. Além desses, nos acervos digitais da Fundação Biblioteca Nacional e Center Research for Libraries. Ao final deste estudo, identifiquei que as relações entre os deslocamentos espaciais do Chafariz Imperador e as transformações da paisagem urbana de Porto Alegre, estão associadas à Cultura Política dos grupos detentores do poder. Verifiquei que apenas, mais recentemente, as decisões quanto à localização e à preservação do monumento passam a ser tratadas por agentes públicos especializados que se ocupam do Patrimônio Cultural da cidade. / This study identifies factors related to geographical displacements of the Emperor Fountain. It is a monument installed in the late 1866 and in the beginning of 1867, in Matriz square in Porto Alegre (RS), the Porto Alegrense Hydraulic Company due to the celebration of the start of the drinking water supply to Porto Alegre´s citizens. Nowadays, some remaining parts of the fountain are located in Dom Sebastião square, in the city´s downtown. The rebuilding of the historical trajectory of the monument between the periods of 1866-2013 took place from a documental research of qualitative focus in the following places: Vellinho Moyses Historical Archive of Porto Alegre, Historical Archive of Rio Grande do Sul state, Hippolytus José da Costa Museum of Communication, Joaquim José Felizardo Museum. In addition to these places, in the digital collections of the National Library Foundation and in the Center Research for Libraries. At the end of this study, I identified relationships between spatial displacements of the Emperor Fountain and the changes of Porto Alegre´s urban landscape, which are connected to the Political Culture of the most powerful and influent groups of the city. I also noticed that only recently, the decisions regarding the location and preservation of the monument began to be treated by specialized public officials dealing with the city´s cultural heritage.