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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
251

A realização interacional de atividades pedagógicas em uma sala de aula de língua adicional pautada por projetos : reflexões para o planejamento de tarefas pedagógicas além do enunciado

Salimen, Paola Guimaraens January 2016 (has links)
O objetivo desta tese é relacionar análises de segmentos transcritos de fala-em-interação de sala de aula de língua adicional e orientações acerca de metodologia de ensino. Em especial, esta pesquisa propõe colocar em discussão as orientações presentes em manuais de metodologia de ensino de línguas adicionais (Brown, 2007; Hall, 2001a; Harmer, 2009; Schlatter & Garcez, 2012; Scrivener, 2012) acerca do planejamento de tarefas pedagógicas e do gerenciamento interacional da participação dos alunos durante a realização de atividades pedagógicas. Para a realização do estudo, foram geradas 20 horas de registros audiovisuais em uma sala de aula de nível básico 2 de português como língua adicional que adota pedagogia de projetos em um curso em extensão de uma instituição federal de ensino superior. A partir do enquadre teórico-metodológico da Análise da Conversa, analiso neste relatório cinco ocorrências transcritas (de um total de dezoito) de fala-em-interação de sala de aula em que o status epistêmico de conhecedor da língua adicional de algum participante é posto em risco durante a realização de atividades pedagógicas. A realização de atividades pedagógicas foi analisada como constituída de três etapas: convite à participação (Ramos, 2010), produção e continuidade. Observou-se que as ações realizadas na etapa de continuidade da realização da atividade pedagógica foram centrais para a concretização de diferentes objetivos pedagógicos. Quando essas ações estavam implicadas sequencialmente em relação ao que fora feito imediatamente antes na etapa de produção da atividade pedagógica, o objetivo concretizado se relacionava ao uso da língua adicional para a realização de ações. Por outro lado, quando essas ações não exibiam essa implicatividade sequencial, o objetivo realizado dizia respeito à produção de elocuções com acurácia. Verificou-se que as ações realizadas pela professora que rebaixavam o outro participante epistemicamente com relação à língua adicional foram ofertas de reelaboração de elocuções. Já as práticas e ações mobilizadas pela professora que trabalhavam no sentido de assegurar o status epistêmico dos demais participantes como conhecedores da língua adicional foram a formulação (Garfinkel & Sacks, 1970) e a verificação de entendimento (Schegloff, Jefferson, & Sacks, 1977, pp. 379). Tais achados recomendam que manuais de metodologia de ensino de línguas atentem para a importância de a) antever, quando do planejamento de tarefas, a interação projetada na etapa de continuidade da tarefa de modo a maximizar a chance de que os objetivos projetados se concretizem e b) considerar as ações de formulação e verificação de entendimento como centrais para a materialização da atribuição do professor como ratificador do conhecimento produzido pelo aluno. / This thesis is aimed at relating classroom talk-in-interaction transcripts to guidelines on teaching methodology. This research discusses guidelines from additional languague teaching methodology handbooks (Brown, 2007; Hall, 2001a; Harmer, 2009; Schlatter & Garcez, 2012; Scrivener, 2012) on task planning and interactional management of students’ participation while carrying out pedagogical activities. Twenty hours of audiovisual data were generated in a Portuguese-as-an-additional language extension program at a Higher Education institution. The classes registered were a basic 2 level group, whose curriculum followed a progect-based methodology. Following Conversation Analysis framework, I analyse five transcribed segments (from a corpus of eighteen occurances) that portray participants’ epistemic status K+ concerning the additional language at risk during the accomplishment of pedagogical activities. The accomplishment of the pedagogical activity was constituted in three stages: invite for participation (Ramos, 2010), production and follow up. The actions co-constructed during the follow up stage were crucial to reach different pedagogical goals. When such actions were sequentially implied in relation to the action previously done in the production stage of the pedagogical activity, the goal reached was connected to a concept of language as doing social actions. On the other hand, when these actions did not display such sequential implication, the pedagogical goal was connected to accurate language production. The actions produced by the instructor that downgraded the other participant epistemic status in relation to the additional language were offers of reformulated utterances. The practices and actions that ratified the other participants’ epistemic status as K+ in relation to the additional langauge were formulations (Garfinkel & Sacks, 1970) and comprehension checks (Schegloff, Jefferson, & Sacks, 1977, pp. 379). Such findings suggest that additional language teaching handbooks take notice of a) the importance of predicting and projecting the actions to be done during the follow up stage so as to maximize the chances of reaching the pedagogical goals previously planned and b) the actions of formulating and checking understanding as central resources to enable the additional language instructor to ratify others’ production (and knowledge) in the additional language at hand.
252

A Study of the Problems of College Freshmen and the Effects of one Semester of College Attendance on Those Problems

Reeder, Thelma A. 08 1900 (has links)
"The problem of this study is to determine, by means of a statistical analysis of the results from the Mooney Problem Check List given to 1011 students at North Texas State College during the year 1949-50, what the problems of college freshmen are and if there is a significant change in the areas in which those problems are found from one semester to another."--1-2.
253

Évaluation de l’implantation, des processus et des effets différentiels de Check & Connect : un programme de prévention de l’abandon scolaire

Goulet, Mélissa 08 1900 (has links)
L’objectif de cette thèse était d’évaluer l’implantation, les effets différentiels et les processus du programme Check & Connect (C&C), une intervention visant la prévention de l’abandon scolaire. De nature ciblée, cette intervention s’adresse aux élèves à risque de décrochage scolaire. Par le biais de la création d’une relation significative avec un mentor, du monitorage systématique des indicateurs de désengagement scolaire, d’interventions différentielles adaptées aux besoins des élèves et de la communication positive avec la famille de ces derniers, ce programme développé aux États-Unis au début des années 1990 a été maintes fois évalué en sol américain. Cette évaluation s’intéresse à l’adaptation québécoise du programme, réalisée dans deux commissions scolaires de la grande région de Montréal, et ce tant au niveau primaire qu’au niveau secondaire. L’évaluation de l’implantation, des effets différentiels et des processus s’insère dans un projet plus vaste de validation écologique du programme réalisée à l’aide d’un devis expérimental dans le cadre duquel le groupe contrôle équivalent a reçu les interventions typiquement prévues dans les écoles : l’intervention C&C est donc comparée aux interventions typiquement mises en place dans les écoles pour les élèves à risque d’abandon scolaire. L’évaluation de l’implantation et des effets différentiels a été réalisée à la suite des deux années d’implantation auprès des 345 élèves du primaire et du secondaire ayant été exposés au programme et des 54 mentors impliqués. La fidélité d’implantation a été évaluée en relation avec les effets du programme à l’aide d’analyses quantitatives de fréquence et de régressions linéaires. L’évaluation des processus a également été réalisée une fois l’implantation terminée; des entrevues semi-structurées ont été réalisées auprès de 12 acteurs impliqués dans l’implantation. Des analyses thématiques, puis des études de cas ont été complétées afin d’explorer les processus d’implantation. Le premier chapitre empirique de la thèse présente l’évaluation de l’implantation et des effets différentiels du programme C&C. Cette étude a permis de constater des taux de fidélité d’implantation variables d’une composante du programme à l’autre, et d’un site d’implantation à un autre. De plus, les résultats révèlent que la fidélité d’implantation est associée aux effets du programme sur l’engagement et le rendement scolaires. Néanmoins, cette association varie grandement d’une composante du programme et d’un site d’implantation à un autre, ce qui suggère d’importantes influences contextuelles sur l’implantation. Le second chapitre empirique de la thèse présente l’évaluation des processus d’implantation de C&C dans 4 cas de figure distincts. Cette évaluation révèle de nombreux processus ayant influencé l’expérience d’implantation des acteurs interrogés. Les résultats suggèrent par ailleurs une influence dynamique des processus : des parallèles sont faits avec une théorie issue de la psychologie organisationnelle, la théorie du changement planifié, qui suggère la considération de l’implantation d’un programme d’intervention comme un changement de pratiques. En somme, les évaluations présentées dans la thèse soutiennent d’une part l’importance d’une implantation fidèle lorsque vient le temps de faire appel à un programme d’intervention. La thèse suggère de surcroît la nécessité de s’assurer d’une préparation adéquate et de la mise en place de conditions optimales pour l’intervenant et l’organisation désirant implanter un programme d’intervention en milieu scolaire, puisque la fidélité d’implantation n’est pas garante à elle seule d’effets positifs suite à l’implantation. / The present thesis aimed to evaluate the implementation, differential effects and processes of Check & Connect (C&C), a dropout prevention program. This targeted intervention promotes the development of a significant relationship with a mentor in addition to the use of systematic monitoring of disengagement indicators, differential and adapted interventions and positive school-family communication in order to help students at risk of dropping out of school. Developed in the 1990s in the United States, this program was evaluated many times in American school settings. This evaluation focuses on a French-Canadian adaptation of C&C, implemented in elementary and secondary schools of two school boards in the Montreal area. The evaluation of the implementation, implementation processes, and differential effects is part of a larger ecological and experimental validation of the program in which students of the control group received the usual interventions typically offered to at-risk students in their schools. Implementation and differential effects evaluations were conducted after the two-year implementation of C&C among a sample of 345 elementary and secondary-level students and their 54 mentors. Implementation fidelity and its relations to program effects were evaluated using frequency analyses and linear regressions. Process evaluation was also completed post-intervention: semi-structured interviews were conducted with 12 actors directly involved in the implementation. Qualitative thematic analyses and case studies were then completed in order to explore implementation processes. The first empirical chapter of this thesis presents the evaluations of C&C’s implementation and differential effects. This evaluation revealed high variability in implementation fidelity rates from one program component to another, and across implementation sites. Further, results suggest that implementation fidelity is associated to C&C’s effects on student engagement and achievement. Nevertheless, that relation varies from one program component to another and based on implementation context. The second empirical chapter of the thesis presents the evaluation of C&C’s process in four distinct cases. This evaluation reveals that many processes influenced the implementation experience of interviewed actors. Results also show the dynamic influences of implementation processes. These dynamics are illustrated using a theory originating from organizational psychology: the Theory of Planned Change, which presents the implementation of an intervention program as a change in practices. In conclusion, the evaluations presented in this thesis first support the importance of implementation fidelity and context to achieve the desired effects when instigating an intervention program. For professionals and organizations interested in implementing an intervention program in a school setting, results further suggest the importance of adequate preparation and optimal implementation conditions, since implementation fidelity in itself is not sufficient to ensure positive intervention results.
254

Méthodes garanties pour l’estimation d’état et le contrôle de cohérence des systèmes non linéaires à temps continu

Videau, Gaétan 17 July 2009 (has links)
Cette thèse traite des problèmes d’estimation et de contrôle de cohérence par l’utilisation des techniques ensemblistes. L’objectif est la mise en place d’une démarche méthodologique pour la surveillance et la détection d’anomalies au sein des systèmes où le déterminisme des indicateurs relatifs à l’état de santé du système est une condition sine qua non. Une fois placé dans un contexte ensembliste, l’évolution de chaque variable du système est représentée par une enveloppe traduisant les incertitudes internes et externes ; cette enveloppe représente le seuil au delà duquel le comportement observé représente un écart anormal par rapport à son comportement nominal, et pouvant conduire à une incapacité pour accomplir les objectifs de sa mission. Les techniques développées sont appliquées à un procédé hydraulique de laboratoire . / This work deals with the development of set-membership methods for set esti- mation and consistency checks for nonlinear continuous-time systems. The main objective is to setup a methodology for fault detection and isolation for the systems where the deter- minism of faults indicators on the health system is a necessary condition. Once placed in a set-membership framework, the evolution of each variable is represented by an envelope re?ecting the internal and external uncertainties. This envelope corresponds to the threshold beyond which the observed behavior is an abnormal discrepancy over its nominal behav- ior, thus preventing the accomplishment the mission objectives. The proposed methods are applied on a hydraulic laboratory process.
255

Elaboração e aplicação de uma ferramenta de avaliação de estruturas físicas, leiaute e materiais de construção utilizados em cozinhas industriais com impacto na segurança de alimentos

Perini, Fabiana Oliveira January 2018 (has links)
Este estudo teve como objetivo o desenvolvimento de uma ferramenta para avaliar estruturas físicas, leiaute e materiais de construção de cozinhas industriais. Na primeira etapa do trabalho, diversas legislações sanitárias e documentos técnicos foram avaliados, a fim de identificar itens pertinentes à construção da ferramenta. Com base nisso, foram elaboradas 196 perguntas, divididas em 24 itens, as quais compuseram a ferramenta de avaliação de estruturas (check-list). O check-list foi encaminhado para especialistas da área de segurança de alimentos, para que estes verificassem a adequação das perguntas e conferissem pesos para cada uma delas, conforme a possibilidade na contaminação e o impacto na segurança dos alimentos. O peso 1 (um) foi atribuído aos itens da estrutura física das cozinhas, que poderiam causar impacto na segurança de alimentos, porém que dificilmente resultariam em contaminação dos alimentos ou causariam surtos alimentares, como, por exemplo, as áreas externas, portas externas e fechamento automático de portas de sanitários. O peso 2 (dois) foi atribuído às perguntas sobre a estrutura física da cozinha que poderiam causar contaminação indireta nos alimentos, exemplos: portas internas ajustadas aos pisos e batentes, caixas de gordura e de esgoto compatíveis ao volume de resíduos, entre outros. O peso 4 (quatro) foi atribuído às questões sobre a estrutura física das cozinhas que poderiam causar contaminação direta aos alimentos, como, por exemplo, estrutura dos telhados e tetos, áreas de produção com fluxo linear, entre outras Após a revisão do check-list, foram retiradas as perguntas que não foram consideradas pertinentes ao setor de alimentação e então foi calculado um peso médio para cada pergunta, tendo como base os pesos atribuídos por cada avaliador. A versão final do check-list resultou em 23 itens, compostos por 126 perguntas. Na segunda etapa do trabalho, foi realizada a utilização prática do check-list com o objetivo de testar a aplicação da ferramenta de avaliação e identificar os problemas mais frequentes na construção civil de cozinhas industriais. Para tanto, as cozinhas industriais existentes na região metropolitana de Porto Alegre/RS (RMPA) foram consideradas e identificadas como o universo da pesquisa, possibilitando a visita a um número significativo de cozinhas industriais. O número de cozinhas identificado na RMPA foi de 248 unidades, das quais 52 foram visitadas. Para avaliar cada unidade visitada com relação à adequação sanitária de suas instalações, foi elaborado o Índice Sanitário de Edificações (ISE). O ISE é uma média harmônica ponderada dos itens aplicáveis, a qual leva em consideração os pesos conferidos a cada pergunta e se o item foi conforme ou não. As respostas do check-list foram analisadas no Microsoft Excel 2010 e a análise estatística foi realizada no programa IBM® SPSS® STATISTICS versão 18.0, adotando o nível de significância de 5% As principais não conformidades observadas foram infiltrações, goteiras, tubulações sem capacidade para vazão adequada, pias e sifões entupidos, pouca quantidade de ralos, caimento dos pisos, caixa de gordura, pouca luminosidade, ventilação e conforto térmico. Do total de unidades avaliadas, 1 (2%) apresentou índice de adequação excelente, 14 (27%) índice de adequação bom, 32 (61%) índice de adequação médio e 5 (10%) índice de adequação ruim. Além do índice de adequação ao check-list, foi calculado um índice de adequação aos itens requeridos por legislação. O volume de empresas que apresentaram índices entre os níveis de adequação excelente e bom aumentou quando comparado ao índice de adequação ao chek-list, passando para 4 (8%) com índice excelente, 27 (51%) com índice bom, 20 (39%) com índice médio e 1 (2%) com índice ruim. Os resultados indicam que as cozinhas industriais apresentaram inadequações em suas instalações, já que em sua maioria apresentaram índices medianos ou inferiores de adequação aos itens da legislação e ao ISE. Cozinhas com estas falhas nas instalações podem ter prejudicadas suas condições higiênico- sanitárias do processo, trazendo riscos potenciais para a produção de alimentos. Com a identificação dos problemas nas edificações e leiutes, pôde- se indicar soluções para contribuir na gestão de segurança dos alimentos em serviços de alimentação, prevenindo a contaminação de alimentos. / This study aimed to develop a tool to evaluate physical structures, layout and materials of industrial kitchens. In the first stage of the work, several sanitary legislations and technical documents were evaluated in order to identify items pertinent to the construction of the tool. Based on this, check-list tool were elaborated containing196 questions, divided into 24 items. The checklist was assessed to food safety experts to verify the appropriateness of the questions and to check weights for each one, depending on the possibility of contamination and impact on food safety. Weight 1 (one) was attributed to the items in the kitchen's physical structure, which could impact on food safety, but would hardly result in contamination of food or food outbreaks, such as external areas, external doors and automatic door closing of toilets. Weight 2 (two) was attributed to the questions about the physical structure of the kitchen that could cause indirect contamination in the food, some examples: internal doors adjusted to the floors and stops, fat and sewage boxes compatible with the volume of waste. Weight 4 (four) was attributed to questions about the physical structure of the kitchen that could cause direct contamination of food, such as the structure of roofs and ceilings, production areas with linear flow. After reviewing the checklist, the questions that were not considered pertinent to the food sector were removed, and then an average weight was calculated for each question, based on the weights assigned by each evaluator The final version of the checklist resulted in 23 items consisting of 126 questions. In the second stage of the work, the practical check-list was used, with the objective of testing the application of the evaluation tool and identifying the most frequent problems in the civil construction of industrial kitchens. To this end, the industrial kitchens in the metropolitan area of Porto Alegre / RS (RMPA) were considered and identified as the research universe, allowing the visit of a significant number of industrial kitchens. The number of kitchens identified in the RMPA was 248 units, of which 52 were visited. To evaluate each unit visited in relation to the sanitary adequacy of its facilities, the Sanitary Building Index (ISE) was elaborated. The ISE is a weighted harmonic mean of the applicable items, which takes into account the weights given to each question and whether or not the item was compliant. The checklist responses were analyzed in Microsoft Excel 2010 and statistical analyzes were performed using the IBM® SPSS® STATISTICS version 18.0 program, adopting the 5% significance level. The main nonconformities observed were infiltrations, gutters, pipes with no adequate flow capacity, clogged sinks and siphons, few drains, floor trim, grease box, low luminosity, ventilation and thermal comfort Of the total number of units evaluated, 1 (2%) presented an excellent suitability index, 14 (27%) were adequately matched, 32 (61%) were adequately matched, and 5 were considered adequately matched. In addition to the index of adequacy to the checklist, an index of adequacy to the items required by legislation was calculated. The volume of companies that presented excellent and good levels of adequacy increased when compared to the index of adequacy to the former chek-list, passing to 4 (8%) with excellent index, 27 (51%) with good index, 20 (39 %) with average index and 1 (2%) with poor index. The results indicate that the industrial kitchens presented inadequacies in their facilities, since in their majority they presented medium or inferior indexes of adequacy to the items of the legislation and the ISE. Kitchens with these facility failures may have impaired their hygienic-sanitary conditions of the process, bringing potential risks to food production. With the identification of problems in buildings and law, it was possible to indicate solutions to contribute to the management of food safety in food services, preventing the contamination of food.
256

Návrhy na zlepšení hospodaření s dlouhodobým hmotným majetkem / Improvement Proposals for Long Term Asset Management of a Company

Bělehrádek, Tomáš January 2016 (has links)
Master thesis deals with the management of tangible fixed assets in the company Ecolab Hygiene s.r.o. which is engaged in purchase and sale of cleaning, desinfectant and sanitazing detergents, rental and repairs of cleaning machines and equipement. Introductory part is focused on theoretical bases. Second part of the thesis is focused on analysis of tanglibe fixed assets in the company and property maintenance. Based on analysis established knowledge there are subsequently weaknesses identified. In the final part solutions are proposed including their economic aspect whose implementation should have possitive impact on the current status improvement.
257

Efficient architectures for error control using low-density parity-check codes

Haley , David January 2004 (has links)
Recent designs for low-density parity-check (LDPC) codes have exhibited capacity approaching performance for large block length, overtaking the performance of turbo codes. While theoretically impressive, LDPC codes present some challenges for practical implementation. In general, LDPC codes have higher encoding complexity than turbo codes both in terms of computational latency and architecture size. Decoder circuits for LDPC codes have a high routing complexity and thus demand large amounts of circuit area. There has been recent interest in developing analog circuit architectures suitable for decoding. These circuits offer a fast, low-power alternative to the digital approach. Analog decoders also have the potential to be significantly smaller than digital decoders. In this thesis we present a novel and efficient approach to LDPC encoder / decoder (codec) design. We propose a new algorithm which allows the parallel decoder architecture to be reused for iterative encoding. We present a new class of LDPC codes which are iteratively encodable, exhibit good empirical performance, and provide a flexible choice of code length and rate. Combining the analog decoding approach with this new encoding technique, we design a novel time-multiplexed LDPC codec, which switches between analog decode and digital encode modes. In order to achieve this behaviour from a single circuit we have developed mode-switching gates. These logic gates are able to switch between analog (soft) and digital (hard) computation, and represent a fundamental circuit design contribution. Mode-switching gates may also be applied to built-in self-test circuits for analog decoders. Only a small overhead in circuit area is required to transform the analog decoder into a full codec. The encode operation can be performed two orders of magnitude faster than the decode operation, making the circuit suitable for full-duplex applications. Throughput of the codec scales linearly with block size, for both encode and decode operations. The low power and small area requirements of the circuit make it an attractive option for small portable devices.
258

Large Scale Content Delivery applied to Files and Videos

Neumann, Christoph 14 December 2005 (has links) (PDF)
Le multicast fiable est certainement la solution la plus efficace pour la distribution de contenu via un<br />tres grand nombre (potentiellement des millions) de recepteurs. Dans cette perspective les protocoles<br />ALC et FLUTE, standardises via l'IETF (RMT WG), ont ete adoptes dans 3GPP/MBMS et dans le<br />DVB-H IP-Datacast dans les contextes des reseaux cellulaires 3G.<br />Ce travail se concentre sur le multicast fiable et a comme requis principal le passage l'echelle massif<br />en terme de nombre de clients. Cette these se base sur les solutions proposees via l'IETF RMT WG.<br />Ces protocoles de multicast fiable sont construit autour de plusieurs briques de base que nous avons<br />etudie en detail:<br />* La brique Forward Error Correction (FEC) :<br />Nous examinons la classe de codes grands blocs Low Density Parity Check (LDPC). Nous concevons<br />des derivees de ces codes, et les analysons en detail. Nous en concluons que les codes<br />LDPC et leur implementation ont des performances tres prometteuses, surtout si ils sont utilisees<br />avec des fichiers de taille importante.<br />* La brique controle de congestion :<br />Nous examinons le comportement dans la phase de demarrage de trois protocoles de controle de<br />congestion RLC, FLID-SL, WEBRC. Nous demontrons que la phase de demarrage a un grand<br />impact sur les performances de telechargement.<br />Cette these a aussi plusieurs contributions au niveau applicatif:<br />* Extensions de FLUTE :<br />Nous proposons un mecanisme permettant d'agreger plusieurs fichiers dans le protocole FLUTE.<br />Ceci ameliore les performance de transmission.<br />* Streaming video :<br />Nous proposons SVSoA, une solution de streaming base sur ALC. Cette approche beneficie de<br />tout les avantages de ALC en terme de passage a l'echelle, controle de congestion et corrections<br />d'erreurs.<br /><br />Mots cles : Multicast fiable, FLUTE, ALC, codes correcteur d'erreurs, Forward Error Correction<br />(FEC), Low Density Parity Check (LDPC) Codes, diffusion de contenu
259

Low-density Parity-Check decoding Algorithms / Low-density Parity-Check avkodare algoritm

Pirou, Florent January 2004 (has links)
<p>Recently, low-density parity-check (LDPC) codes have attracted much attention because of their excellent error correcting performance and highly parallelizable decoding scheme. However, the effective VLSI implementation of and LDPC decoder remains a big challenge and is a crucial issue in determining how well we can exploit the benefits of the LDPC codes in the real applications. In this master thesis report, following a error coding background, we describe Low-Density Parity-Check codes and their decoding algorithm, and also requirements and architectures of LPDC decoder implementations.</p>
260

Efficient Message Passing Decoding Using Vector-based Messages

Grimnell, Mikael, Tjäder, Mats January 2005 (has links)
<p>The family of Low Density Parity Check (LDPC) codes is a strong candidate to be used as Forward Error Correction (FEC) in future communication systems due to its strong error correction capability. Most LDPC decoders use the Message Passing algorithm for decoding, which is an iterative algorithm that passes messages between its variable nodes and check nodes. It is not until recently that computation power has become strong enough to make Message Passing on LDPC codes feasible. Although locally simple, the LDPC codes are usually large, which increases the required computation power. Earlier work on LDPC codes has been concentrated on the binary Galois Field, GF(2), but it has been shown that codes from higher order fields have better error correction capability. However, the most efficient LDPC decoder, the Belief Propagation Decoder, has a squared complexity increase when moving to higher order Galois Fields. Transmission over a channel with M-PSK signalling is a common technique to increase spectral efficiency. The information is transmitted as the phase angle of the signal.</p><p>The focus in this Master’s Thesis is on simplifying the Message Passing decoding when having inputs from M-PSK signals transmitted over an AWGN channel. Symbols from higher order Galois Fields were mapped to M-PSK signals, since M-PSK is very bandwidth efficient and the information can be found in the angle of the signal. Several simplifications of the Belief Propagation has been developed and tested. The most promising is the Table Vector Decoder, which is a Message Passing Decoder that uses a table lookup technique for check node operations and vector summation as variable node operations. The table lookup is used to approximate the check node operation in a Belief Propagation decoder. Vector summation is used as an equivalent operation to the variable node operation. Monte Carlo simulations have shown that the Table Vector Decoder can achieve a performance close to the Belief Propagation. The capability of the Table Vector Decoder depends on the number of reconstruction points and the placement of them. The main advantage of the Table Vector Decoder is that its complexity is unaffected by the Galois Field used. Instead, there will be a memory space requirement which depends on the desired number of reconstruction points.</p>

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