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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.
11

Semantic Validation of T&E XML Data

Moskal, Jakub, Kokar, Mieczyslaw, Morgan, John 10 1900 (has links)
ITC/USA 2015 Conference Proceedings / The Fifty-First Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2015 / Bally's Hotel & Convention Center, Las Vegas, NV / It is anticipated that XML will heavily dominate the next generation of telemetry systems. The syntax of XML-based languages can be constrained by a schema that describes the structure of valid documents. However, the schemas cannot express all dependencies between XML elements and attributes, both within a single document and across multiple documents. This prohibits the XML validation process from being fully automated with standard schema processors. This paper presents an approach that is based on the W3C Semantic Web technologies and allows different vendors and system integrators to independently develop their own semantic validation rules. The rules are equipped with powerful semantics, which allows for specification and validation of complex types of constraints. The approach is not specific to a particular T&E standard and is entirely standards-based.
12

A questão dos créditos de carbono e sua viabilidade econômica ambiental / The issue of carbon credits and their economic and environmental viability

Calestini, Eduardo Del Nery 26 October 2012 (has links)
As mudanças climáticas provocadas pelo Homem induziram a formação de um mercado que segue atividades que afirmam contemplar aspectos de desenvolvimento sustentável. O mecanismo de desenvolvimento limpo (MDL) é um dos instrumentos de flexibilização estabelecido pelo protocolo de Quioto com o objetivo de facilitar o cumprimento das metas de redução de emissão de gases de efeito estufa (GEE), definidas para os países que o ratificaram, tratando do desenvolvimento e da implantação de projetos visando à redução de emissões de gases de efeito estufa nos países em desenvolvimento, financiado pelos países desenvolvidos, em troca de créditos para serem abatidos dos seus compromissos de redução de emissões. Os projetos que se habilitarem à condição de projeto de MDL deverão cumprir uma série de procedimentos até receber a chancela da ONU e, consequentemente, certificar as reduções alcançadas. O presente trabalho tem o objetivo de analisar quais são os requisitos para a implantação de um MDL e discutir a real promoção da sustentabilidade do dispositivo, bem como a viabilidade econômica e ambiental, conforme preconiza o artigo 12 do Protocolo de Quioto. Para o cumprimento da presente tarefa foi necessária a análise dos antecedentes do Mecanismo de Desenvolvimento Limpo, a saber: As mudanças climáticas globais, a Convenção-Quadro das Nações Unidas sobre Mudança do Clima e o Protocolo de Quioto. Em seguida foram analisados dois projetos utilizando MDL sob dois aspectos diferenciados. O primeiro advindo de reduções de emissões em um aterro sanitário, na cidade de São Paulo, o segundo relacionado à silvicultura, no interior do mesmo Estado. / Climate change caused by man induced the formation of a market that follows activities that claim to include elements of sustainable development. The Clean Development Mechanism (CDM) is one of the Kyoto Protocol flexibilization instruments in order to facilitate the achievement of greenhouse gases (GHGs) emission reducing goals defined for the countries which have ratified it, treating of development and implementation of projects in order to reduce GHGs emission in developing countries, financed by developed countries, in exchange for credits to be deducted from their commitments to reduce emissions. Projects that qualify for CDM project status must meet a series of procedures to receive the United Nation (UN) approval and consequently, certify the achieved reductions. This study aims to examine which are the requirements for implementation of a CDM and discuss the actual promotion of the device sustainability as well as economic and environmental viability, as defined in article 12 of the Kyoto Protocol. In fulfillment of this task it was necessary to analyze the background of the CDM, as follows: Global climate changes, the UN Framework Convention on Climate Change and the Kyoto Protocol. Next, two projects were analyzed using CDM under two different aspects. The first about emission reductions in a landfill, in the city of Sao Paulo, the second related to growing eucalyptus, in the countryside of the same state.
13

Structural change detection via penalized regression

Wang, Bo 01 August 2018 (has links)
This dissertation research addresses how to detect structural changes in stochastic linear models. By introducing a special structure to the design matrix, we convert the structural change detection problem to a variable selection problem. There are many existing variable selection strategies, however, they do not fully cope with structural change detection. We design two penalized regression algorithms specifically for the structural change detection purpose. We also propose two methods involving these two algorithms to accomplish a bi-level structural change detection: they locate the change points and also recognize which predictors contribute to the variation of the model structure. Extensive simulation studies are shown to demonstrate the effectiveness of the proposed methods in a variety of settings. Furthermore, we establish asymptotic theoretical properties to justify the bi-level detection consistency for one of the proposed methods. In addition, we write an R package with computationally efficient algorithms for detecting structural changes. Comparing to traditional methods, the proposed algorithms showcase enhanced detection power and more estimation precision, with added capacity of specifying the model structures at all regimes.
14

Methods and Experiments With Bounded Tree-width Markov Networks

Liang, Percy, Srebro, Nathan 30 December 2004 (has links)
Markov trees generalize naturally to bounded tree-width Markov networks, onwhich exact computations can still be done efficiently. However, learning themaximum likelihood Markov network with tree-width greater than 1 is NP-hard, sowe discuss a few algorithms for approximating the optimal Markov network. Wepresent a set of methods for training a density estimator. Each method isspecified by three arguments: tree-width, model scoring metric (maximumlikelihood or minimum description length), and model representation (using onejoint distribution or several class-conditional distributions). On thesemethods, we give empirical results on density estimation and classificationtasks and explore the implications of these arguments.
15

A questão dos créditos de carbono e sua viabilidade econômica ambiental / The issue of carbon credits and their economic and environmental viability

Eduardo Del Nery Calestini 26 October 2012 (has links)
As mudanças climáticas provocadas pelo Homem induziram a formação de um mercado que segue atividades que afirmam contemplar aspectos de desenvolvimento sustentável. O mecanismo de desenvolvimento limpo (MDL) é um dos instrumentos de flexibilização estabelecido pelo protocolo de Quioto com o objetivo de facilitar o cumprimento das metas de redução de emissão de gases de efeito estufa (GEE), definidas para os países que o ratificaram, tratando do desenvolvimento e da implantação de projetos visando à redução de emissões de gases de efeito estufa nos países em desenvolvimento, financiado pelos países desenvolvidos, em troca de créditos para serem abatidos dos seus compromissos de redução de emissões. Os projetos que se habilitarem à condição de projeto de MDL deverão cumprir uma série de procedimentos até receber a chancela da ONU e, consequentemente, certificar as reduções alcançadas. O presente trabalho tem o objetivo de analisar quais são os requisitos para a implantação de um MDL e discutir a real promoção da sustentabilidade do dispositivo, bem como a viabilidade econômica e ambiental, conforme preconiza o artigo 12 do Protocolo de Quioto. Para o cumprimento da presente tarefa foi necessária a análise dos antecedentes do Mecanismo de Desenvolvimento Limpo, a saber: As mudanças climáticas globais, a Convenção-Quadro das Nações Unidas sobre Mudança do Clima e o Protocolo de Quioto. Em seguida foram analisados dois projetos utilizando MDL sob dois aspectos diferenciados. O primeiro advindo de reduções de emissões em um aterro sanitário, na cidade de São Paulo, o segundo relacionado à silvicultura, no interior do mesmo Estado. / Climate change caused by man induced the formation of a market that follows activities that claim to include elements of sustainable development. The Clean Development Mechanism (CDM) is one of the Kyoto Protocol flexibilization instruments in order to facilitate the achievement of greenhouse gases (GHGs) emission reducing goals defined for the countries which have ratified it, treating of development and implementation of projects in order to reduce GHGs emission in developing countries, financed by developed countries, in exchange for credits to be deducted from their commitments to reduce emissions. Projects that qualify for CDM project status must meet a series of procedures to receive the United Nation (UN) approval and consequently, certify the achieved reductions. This study aims to examine which are the requirements for implementation of a CDM and discuss the actual promotion of the device sustainability as well as economic and environmental viability, as defined in article 12 of the Kyoto Protocol. In fulfillment of this task it was necessary to analyze the background of the CDM, as follows: Global climate changes, the UN Framework Convention on Climate Change and the Kyoto Protocol. Next, two projects were analyzed using CDM under two different aspects. The first about emission reductions in a landfill, in the city of Sao Paulo, the second related to growing eucalyptus, in the countryside of the same state.
16

Applications de la théorie de l'information à l'apprentissage statistique / Applications of Information Theory to Machine Learning

Bensadon, Jérémy 02 February 2016 (has links)
On considère ici deux sujets différents, en utilisant des idées issues de la théorie de l'information : 1) Context Tree Weighting est un algorithme de compression de texte qui calcule exactement une prédiction Bayésienne qui considère tous les modèles markoviens visibles : on construit un "arbre de contextes", dont les nœuds profonds correspondent aux modèles complexes, et la prédiction est calculée récursivement à partir des feuilles. On étend cette idée à un contexte plus général qui comprend également l'estimation de densité et la régression, puis on montre qu'il est intéressant de remplacer les mixtures Bayésiennes par du "switch", ce qui revient à considérer a priori des suites de modèles plutôt que de simples modèles. 2) Information Geometric Optimization (IGO) est un cadre général permettant de décrire plusieurs algorithmes d'optimisation boîte noire, par exemple CMA-ES et xNES. On transforme le problème initial en un problème d'optimisation d'une fonction lisse sur une variété Riemannienne, ce qui permet d'obtenir une équation différentielle du premier ordre invariante par reparamétrage. En pratique, il faut discrétiser cette équation, et l'invariance n'est plus valable qu'au premier ordre. On définit l'algorithme IGO géodésique (GIGO), qui utilise la structure de variété Riemannienne mentionnée ci-dessus pour obtenir un algorithme totalement invariant par reparamétrage. Grâce au théorème de Noether, on obtient facilement une équation différentielle du premier ordre satisfaite par les géodésiques de la variété statistique des gaussiennes, ce qui permet d'implémenter GIGO. On montre enfin que xNES et GIGO sont différents dans le cas général, mais qu'il est possible de définir un nouvel algorithme presque invariant par reparamétrage, GIGO par blocs, qui correspond exactement à xNES dans le cas Gaussien. / We study two different topics, using insight from information theory in both cases: 1) Context Tree Weighting is a text compression algorithm that efficiently computes the Bayesian combination of all visible Markov models: we build a "context tree", with deeper nodes corresponding to more complex models, and the mixture is computed recursively, starting with the leaves. We extend this idea to a more general context, also encompassing density estimation and regression; and we investigate the benefits of replacing regular Bayesian inference with switch distributions, which put a prior on sequences of models instead of models. 2) Information Geometric Optimization (IGO) is a general framework for black box optimization that recovers several state of the art algorithms, such as CMA-ES and xNES. The initial problem is transferred to a Riemannian manifold, yielding parametrization-invariant first order differential equation. However, since in practice, time is discretized, this invariance only holds up to first order. We introduce the Geodesic IGO (GIGO) update, which uses this Riemannian manifold structure to define a fully parametrization invariant algorithm. Thanks to Noether's theorem, we obtain a first order differential equation satisfied by the geodesics of the statistical manifold of Gaussians, thus allowing to compute the corresponding GIGO update. Finally, we show that while GIGO and xNES are different in general, it is possible to define a new "almost parametrization-invariant" algorithm, Blockwise GIGO, that recovers xNES from abstract principles.
17

Verification, Validation and Completeness Support for Metadata Traceability

Darr, Timothy, Fernandes, Ronald, Hamilton, John, Jones, Charles 10 1900 (has links)
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / The complexity of modern test and evaluation (T&E) processes has resulted in an explosion of the quantity and diversity of metadata used to describe end-to-end T&E processes. Ideally, it would be possible to integrate metadata in such a way that disparate systems can seamlessly access the metadata and easily interoperate with other systems. Unfortunately, there are several barriers to achieving this goal: metadata is often designed for use with specific tools or specific purposes; metadata exists in a variety of formats (legacy, non-legacy, structured and unstructured metadata); and the same information is represented in multiple ways across different metadata formats.
18

Potencial de geração de créditos de carbono e perspectivas de modernização do setor sucroalcooleiro do Estado de São Paulo através do mecanismo de desenvolvimento limpo / Potential Carbon Credits Generation and Modernization Perspectives of the São Paulo State Sugarcane Sector trough the Clean Development Mechanism

Lora, Beatriz Acquaro 18 December 2008 (has links)
A necessidade mundial de mitigação dos gases de efeito estufa (GEE) e a mobilização internacional para atingir os objetivos de redução estabelecidos pela Convenção-Quadro das Nações Unidas para Mudanças Climáticas (CQNUMC) deram abertura para que finalmente as energias renováveis pudessem ser utilizadas e aumentassem sua parcela na matriz energética mundial. No Brasil, a sólida indústria sucroalcooleira atualmente desenvolve projetos de redução de emissões de carbono no âmbito do Mecanismo de Desenvolvimento Limpo (MDL) do Protocolo de Quioto, por meio de 18 projetos baseados na geração de energia elétrica renovável excedente através da cogeração, com exportação para a rede elétrica nacional, deslocando energia marginal termelétrica de origem fóssil, em apenas 20 unidades produtoras paulistas. Neste trabalho foi projetado um cenário ideal de reduções de emissões, que considerou a adesão total de 151 usinas paulistas para a safra de 2006/2007, para cinco cenários patamares tecnológicos de cogeração, com queima de bagaco e também aproveitamento da palha. Foi utilizando os parâmetros tecnológicos elaborados pela Comissão Especial de Bioenergia do Governo do Estado de São Paulo e o fator de linha de base de 0,268 tCO2e/MWh adotado pelos projetos de MDL em operação no Estado de São Paulo. No cenário tecnológico mais conservador as emissões evitadas somariam 1.404.593 tCO2e/ano. Para o cenário ideal as emissões evitadas somam 12.199.443 tCO2e/ano. Para composição do cenário ideal também foram calculadas as emissões referentes à queima da palha da cana-de-açúcar. / The world-wide necessity of Greenhouse Gases (GHG) mitigation and the intergovernmental mobilization to reach the objectives established by the United Nations Framework on Climate Change (UNFCCC) has opened space for the renewable energy increase in the worlds energy matrix. In Brazil, the solid sugarcane industry currently develops business in the scope of the Clean Development Mechanism (CDM) under the Kyotos Protocol, by means of 18 biomass-based projects, with renewable energy generation through bagasse cogeneration at 20 São Paulo States sugarcane production units. The projects activitys consists of increasing the efficiency in the bagasse cogeneration facilities, qualifying the units to sell surplus electricity to the national grid, avoiding the dispatch of same amount of energy produced by fossil-fuelled thermal plants to that grid. The reduced emissions are measured in carbon equivalent and can be converted into negotiable credits. The objective of this dissertation was to build a state of art scenario, calculating the potential emissions reduction through CDM projects for the sugarcane sector of São Paulo State, in which we consider the adherence of all the production units of the State to the CDM projects. The technological parameters used to elaborate the scenario were provided by the São Paulo State Government Bioenergy Special Commission and the baseline factor used of 0,268 tCO2e/MWh was that adopted by the CDM projects in operation in the State. The sugarcane database for the calculations was the production ranking provided by UNICA for the 2006/2007 season. In the most conservative scenario 131 units could avoid the emission of 1.404.593 tCO2e/year. For state of art scenario, the units could avoid 12.199.443 tCO2e/year. Also have been calculated the sugarcane straw burning emission for the sugarcane harvested in 2006/2007 season.
19

Perspectivas da geração de créditos de carbono com base na obtenção de um fertilizante - aproveitamento de resíduos de biomassa da agricultura brasileira / Perspectives of the generation of carbon credits on the basis of the attainment of a fertilizer - exploitation of residues of biomass of brazilian agriculture

Bernardi, Caterina Velleca 04 December 2009 (has links)
Neste trabalho, cujo enfoque é inédito na literatura, apresentam-se as principais diretrizes para a implementação de um Mecanismo de Desenvolvimento Limpo, bem como as possibilidades de geração de Redução Certificada de Emissão e sua valoração. Por meio de sistemas adequados, indicados em literatura, estimaram-se as quantidades de gás carbônico que poderiam ser obtidos, elegendo-se para este trabalho, o processo de gaseificação de resíduos de biomassa em algumas culturas agrícolas brasileiras. Em relação ao gás carbônico gerado no processo sugere-se, para avaliar a obtenção de créditos de carbono, que sua captura seja feita através da sua fixação na produção de um fertilizante, que teve seu valor estimado no mercado. Para comprovar essa possibilidade fizeram-se experimentos em escala laboratorial, retendo-se o CO2 em hidróxido de amônio. Análises termogravimétricas, espectroscopia no infravermelho, de difração de raios-X e CHN comprovaram a obtenção do bicarbonato de amônio. Para os valores numéricos foram consultadas nas bibliografias referentes, as culturas agrícolas brasileiras com índices de produção de resíduos conhecidos, estabelecendo-se então uma base de dados numéricos para a formação dos valores correspondentes. Os resultados deste trabalho permitem afirmar que existe uma grande potencialidade para o aproveitamento dos gases resultantes da gaseificação dos resíduos de biomassa, principalmente do gás carbônico na produção de um fertilizante e, com a possibilidade de implementação de um Mecanismo de Desenvolvimento Limpo no país. / In this work, whose approach is unknown in literature, the main lines of direction for the implementation of a Mechanism of Clean Development are presented, as well as the possibilities of generation of Certified Reduction of Emission and its valuation. By means of adjusted systems, indicated in literature, the approach amounts of carbonic gas had been raised that could be gotten, choosing itself for this work, the process of gasification of residues of biomass in some Brazilian agricultural cultures. In relation to the carbonic gas produced in the process it is suggested that to quantify the carbon credits, the capture is made through its setting in the production of a fertilizer that had its approach value searched in the market. To prove this possibility experiments in laboratorial scale had become, holding back the CO2 in the fertilizer ammonium bicarbonate. Termogravimetics analyses, spectra infra-red ray, x-rays diffratograms and CHN had been made and had confirmed that the product was the fertilizer ammonium bicarbonate. For the numerical values, it had been consulted in referring bibliographies, the Brazilian agricultural cultures with indices of production of known residues, establishing then a numerical database for the formation of the corresponding values. The results of this wok allow to affirm that a great potentiality for the exploitation of the resultant gases of the gasification of the residues of biomass, mainly of the carbonic gas in the production of a fertilizer exists and, with the possibility of implementation of a Mechanism of Clean Development in the country.
20

Perspectivas para a cogeração com bagaço de cana-de-açúcar: potencial do mercado de carbono para o setor sucro-alcooleiro paulista / Sugar cane bagasse cogeneration perspective: carbon trade potencial for Sao Paulo sugar-cane sector

Oliveira, Janaína Garcia de 26 February 2007 (has links)
O objetivo do presente trabalho é avaliar o potencial do setor sucro-alcooleiro paulista no mercado de carbono internacional (MCI), sob a perspectiva da cogeração de energia elétrica excedente baseada na queima de bagaço da cana. Estudos com foco nestes dois segmentos podem representar maior incentivo a novos investimentos em projetos para a geração de reduções certificadas de emissões (RCE) sob o mecanismo de desenvolvimento limpo (MDL). O processo de cogeração de energia elétrica por bagaço de cana torna-se importante no contexto mundial devido ao fato de ser uma forma adequada de substituição da queima de combustíveis fósseis pela queima de combustível renovável (bagaço), reduzindo assim, os impactos causados ao meio ambiente pelas emissões de gases do efeito estufa. Essa característica renovável da cogeração, a partir do bagaço da cana, pode fomentar investimentos por países desenvolvidos em projetos que visualizem o atendimento das obrigações de reduções de gases do efeito estufa (GEE), estabelecidas pelo protocolo de Kyoto. Visando atingir o objetivo proposto, foram realizados levantamentos bibliográficos sobre dados setoriais, com base em literatura especializada, simulações computacionais a partir de tais dados para definir o potencial de geração de eletricidade excedente e o potencial de comercialização de RCE pelo setor no mercado de carbono, bem como entrevistas com profissionais ligados às áreas de estudo de forma levantar opiniões e expectativas da participação do setor sucro-alcooleiro no mercado de carbono, foco central deste trabalho. Esta pesquisa visou contribuir para a divulgação da importância do comportamento do setor sucro-alcooleiro paulista em relação ao MC, em termos de atração de novos projetos sob o enfoque do MDL. / The objective of this dissertation is to assess the prospects of cogeneration projects by the sugar-alcohol industry of the largest sugarcane-producing region in Brazil - the state of Sao Paulo - in the context of clean development mechanism (CDM) and of the international carbon credit market. This study with focus in exceeding electricity cogeneration from sugarcane bagasse can influence the development of projects complying with the rules of the CDM, established by the Kyoto protocol. The process of cogeração from sugar cane bagasse becomes important in world-wide context because bagasse burnig substitute fossil fuels, reducing the impacts caused by the greenhouse gases (GHG) emissions. This renewable characteristic of the bagasse electricity cogeneration, can encourage investments from sugar-cane enterprinsing in bagasse cogeneration CDM projects. Aiming to reach the proposed objective, bibliographical research based on specialized literature about sectorial data was done. Computational simulations from such data was used to define the exceeding electricity potencial generation and the certified emission reduction (CER) commercialization potential from sugar-cane sector in the carbon trade and interviews with specialists linked to the study areas. This study can contribute for spreading the importance of the Sao Paulo sugar-alcohol sector in carbon trade, in terms of attract new investiments on clean development mechanisms.

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