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‣ Desenvolvimento de metodologia de projeto de sistema de posicionamento dinâmico aplicado a operações em alto-mar. ; Development of a new methodology for offshore dynamic positioning system design.

Tannuri, Eduardo Aoun
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 20/09/2002 Português
Relevância na Pesquisa
36.866926%
O presente trabalho aborda três tópicos de pesquisa e desenvolvimento em Sistemas de Posicionamento Dinâmico (SPD). Desenvolveu-se uma nova metodologia para o projeto de controlador de posição e aproamento baseada na teoria de controle robusto não-linear por modos deslizantes. O controlador integra uma malha de compensação direta dos esforços ambientais (ondas, vento e correnteza) a uma malha de realimentação que realiza correções de erros residuais. A estrutura não-linear do controlador assegura o desempenho e estabilidade para qualquer aproamento da embarcação. A malha de compensação direta, por sua vez, garante maior faixa de aplicabilidade em termos de condições ambientais, não apresentando degradação de desempenho em condições extremas. A malha de realimentação possui apenas nove parâmetros, existindo equações e regras que tornam suas calibrações simples. Já a malha de compensação direta possui, internamente, modelos para a estimativa das forças ambientais que agem sobre o navio. Graças às características de robustez, o controlador não requer um ajuste refinado dos diversos parâmetros destes modelos e das condições ambientais, podendo-se utilizar estimativas pouco acuradas dos mesmos. O controlador desenvolvido foi testado em simuladores computacionais do VLCC Vidal de Negreiros amarrado pelo sistema turret e de uma barcaça de lançamento de dutos...

‣ SystEM-PLA: um método sistemático para avaliação de arquitetura de linha de produto de software baseada em UML; SystEM-PLA: a systematic evaluation method for UML-based software product line architecture

Oliveira Junior, Edson Alves de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 03/09/2010 Português
Relevância na Pesquisa
37.02017%
A abordagem de linha de produto de software (LP) tem como objetivo principal promover a geração de produtos específicos de um determinado domínio com base na reutilização de uma infraestrutura central, chamada núcleo de artefatos. Um dos principais artefatos do núcleo de uma LP é a Arquitetura de LP (ALP), que representa a abstração de todas as arquiteturas de sistemas únicos que podem ser gerados, para um domínio específico. Avaliações de ALP são importantes, pois permitem aumentar a produtividade e a qualidade dos produtos da LP, bem como, seus resultados permitem a análise de metas de negócio e de retorno de investimento. Este trabalho propõe um método sistemático para avaliação de ALP, o SystEM-PLA (a Systematic Evaluation Method for Software Product Line Architectures). Tal método considera modelos de ALP em UML, por ser uma notação amplamente conhecida e consolidada. SystEM-PLA é composto por um metaprocesso de avaliação, diretrizes que guiam o usuário em como avaliar uma ALP e métricas básicas para modelos UML e atributos de qualidade. O método utiliza a abordagem SMarty (Stereotype-based Management of Variability), para gerenciar variabilidades em LP baseadas em UML. Análises de trade-off com o objetivo de priorizar atributos de qualidade para o desenvolvimento e evolução dos produtos de uma LP são realizadas com base na aplicação e coleta das métricas do SystEM-PLA em configurações de uma ALP. As métricas propostas para os atributos de qualidade complexidade e extensibilidade foram validadas por meio de um estudo experimental. Evidências indicaram a viabilidade de aplicação do método SystEM-PLA na indústria com base em um estudo experimental realizado com profissionais de uma empresa de grande porte no setor de desenvolvimento de software; The software product line (PL) approach aims at promoting the generation of specific products from a particular domain based on the reuse of a central infra-structure...

‣ Indução do sistema citocromo P450 em linhagens de hepatoma humano para utilização como modelo in vitro no desenvolvimento de fármacos; Induction of cytochrome P450 system in human hepatoma cell lines for using as in vitro model in drug development

Matuo, Míriam Cristina Sakuragui
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 31/01/2012 Português
Relevância na Pesquisa
36.790303%
Na etapa inicial do desenvolvimento de novos fármacos, a avaliação do metabolismo e da toxicidade é fundamental para definir seu potencial emprego como candidato a fármaco. Nestes estudos, diversos modelos in vitro são empregados, dentre eles linhagens de hepatoma humano. Entretanto, uma grande limitação ao uso deste modelo in vitro é a baixa expressão das enzimas do sistema citocromo P450. O carotenóide bixina, componente majoritário do anato (urucum), apresentou em estudos in vivo, a capacidade de induzir algumas isoformas do sistema citocromo P450, com a vantagem de apresentar baixa toxicidade. Neste trabalho, a fração lipossolúvel do anato (bixina) e hidrossolúvel (norbixina) foram avaliadas como indutores do sistema citocromo P450 em linhagens de hepatoma humano. Ensaios de MTT, empregando as linhagens HepG2, C3A e SK-HEP-1 indicaram que bixina e norbixina em concentrações abaixo de 0,22 mM são seguras quanto à citotoxicidade. A expressão dos genes CYP 1A1, 1A2, 2C9, 2B6, 2E1 e 3A4 foi avaliada, através de ensaios de RT-PCR em tempo real, em linhagens de hepatoma humano submetidas a tratamento com os compostos bixina e norbixina. Os resultados mostraram que células HepG2 e C3A tratadas com bixina nas concentrações de 0...

‣ Modelos matemáticos aplicados na avaliação da mecânica respiratória em camundongos com desafios de agonista da musculatura lisa.; Mathematical models applied in the assessment of respiratory mechanics in mice with smooth muscle´s agonist challenges.

Aoki, Fabio Gava
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 14/02/2013 Português
Relevância na Pesquisa
37.053997%
Modelos matemáticos são utilizados como ferramentas na avaliação da mecânica respiratória para a compreensão da fisiologia e patologias do sistema respiratório. A presente pesquisa visou avaliar, através da aplicação de modelos matemáticos, a mecânica respiratória em camundongos submetidos à metacolina. Deu-se ênfase no modelo linear de compartimento único e suas variantes não lineares. Camundongos C57BL/6 (n = 8) foram traqueostomizados, ventilados mecanicamente (flexiVent, SCIREQ, Canadá) e perturbações em volume foram aplicadas para a modelagem do sistema respiratório. O protocolo experimental foi elaborado de forma a se analisar a variação dos parâmetros respiratórios durante a aplicação do agente broncoativo e também se verificou a divisão do sinal quasi-senoidal em expirações e inspirações durante a técnica de oscilação forçada (FOT) com perturbação de frequência 2,5 Hz. Com base nisso, uma rotina computacional própria foi desenvolvida para a análise dos experimentos realizados no ventilador mecânico e foram pesquisadas as vantagens e desvantagens dos modelos matemáticos aplicados. Os resultados demonstraram um aumento no desvio padrão dos parâmetros do modelo linear unicompartimental e suas variantes não lineares após a aplicação do broncoconstritor. Acredita-se que esta grande variação nos parâmetros esteja relacionada com o enrijecimento do parênquima e da heterogeneidade da ventilação pulmonar após a utilização da droga. Devido à correlação dos parâmetros do modelo com a fisiologia ocorrer somente no modelo linear...

‣ Ação modulatória da estimulação tátil e do enriquecimento ambiental sobre as respostas hormonais e comportamentais induzidas por estresse crônico, em ratos; The modulatory effects of tactile stimulation and environmental enrichment on hormonal and behavioral responses induced by chronic stress in rats

Rafaela Costa
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 15/12/2014 Português
Relevância na Pesquisa
36.866926%
Dados da Organização Mundial de Saúde mostram que atualmente a depressão atinge 121 milhões de pessoas e deverá ser a doença mais comum no mundo em 2020. Evidências científicas mostram sua associação com o estresse crônico e alterações neuronais relacionadas à depressão, ansiedade, prejuízo no aprendizado e memória. A qualidade do ambiente em que o indivíduo está inserido e o suporte social de que dispõe representam os principais fatores na regulação dessas alterações. Com relação aos mecanismos fisiopatológicos envolvidos nos efeitos do estresse crônico, há estudos que demonstram uma importante associação entre estresse e hiperatividade do sistema renina angiotensina (SRA). Porém, os mecanismos envolvidos na associação entre estresse e depressão e nos efeitos protetores de condições ambientais favoráveis ainda não estão esclarecidos. Em modelo animal, a intervenção ambiental por meio da estimulação tátil ou enriquecimento ambiental tem sido proposta como um fator que poderia diminuir o estresse e promover o bem-estar. No experimento 1, o objetivo deste estudo foi avaliar os efeitos da intervenção ambiental, por meio da estimulação tátil (manipulação) ou enriquecimento ambiental...

‣ Compreensão de representações organizacionais baseadas em abordagens BPM

Magalhães, Ana Cristina Vilela de
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Dissertação de Mestrado
Publicado em 16/12/2008 Português
Relevância na Pesquisa
47.00509%
Dissertação de mestrado em Sistemas de Informação; Hoje em dia, as organizações estão inseridas em ambientes de grande competitividade, deparando-se com grandes desafios, aos quais, necessitam encontrar soluções. Para fazer face a esses desafios, as organizações necessitam de adoptar modelos de gestão baseados em processos. Nesse sentido, surge o Business Process Management que constitui o mais moderno e ambicioso esforço da técnica de software empresarial para abordar a automatização e optimização do funcionamento das empresas e organizações de toda a natureza, antes da necessidade de dotar-se de uma eficácia que permite sobreviver, prosperar e dar o adequado serviço no actual mundo de constantes mudanças. A finalidade de um sistema BPM é decompor a actividade global de uma empresa ou organização, num conjunto de processos, entidades de funcionamento relativamente independentes, que podem ser analisadas com detalhe e cujas acções repetidas podem ser automatizadas; tanto no que concerne aos sistemas, como às pessoas que intervém no mesmo, para optimizar tempos, oportunidades e custos; sem perder a capacidade de adaptação constante e rápida à mudança e conservar a coexistência de métodos seguros com a necessária flexibilidade para facilitar a intervenção activa e fundamental das pessoas e dos processos. O presente estudo visa demonstrar a necessidade de criação de modelos organizacionais no âmbito de abordagens BPM. Foi nossa intenção apreender as dificuldades na aplicação dos modelos e métodos que são sugeridos nas técnicas de modelação consideradas relevantes. O estudo pode ser considerado exploratório pois não procura validar relações de causalidade nem verificar uma teoria. Pretende-se identificar preocupações...

‣ Performance analysis of pressurized irrigation systems operating on-demand using flow-driven simulation models

Calejo, M.J.; Lamaddalena, N.; Teixeira, J.L.; Pereira, L.S.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2008 Português
Relevância na Pesquisa
37.06114%
On-demand pressurized irrigation systems are designed to deliver water with the flow rate and pressure required by the farm irrigation systems, sprinkling or micro-irrigation, and respecting the time, duration and frequency decided by the farmers. Due to the variation in farm demand along the season and the day, a large spatial and temporal variability of flow regimes occurs in these systems, which may affect the performance of the farm systems and the yields of the irrigated crops. Therefore, there is a need to analyse those systems to identify and solve performance problems. In this research, two simulation models for the analysis of irrigation systems operating on-demand, ICARE and AKLA, are used and compared to assess the hydraulic performance of the irrigation network of the Lucefecit Irrigation System, in Southern Portugal. ICARE assesses the global performance of the irrigation system through the indexed characteristic curves, while AKLA provides for the identification of the relative pressure deficit and reliability at every hydrant. Both models adopt a flow-driven analysis approach, performing the analysis for multiple flow regimes. To support the hydraulic characterization of the system and for calibration of the steadystate hydraulic model...

‣ Vascular Endothelial Growth Factor D Is Dispensable for Development of the Lymphatic System

Baldwin, Megan E.; Halford, Michael M.; Roufail, Sally; Williams, Richard A.; Hibbs, Margaret L.; Grail, Dianne; Kubo, Hajime; Stacker, Steven A.; Achen, Marc G.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /03/2005 Português
Relevância na Pesquisa
36.46829%
Vascular endothelial growth factor receptor 3 (Vegfr-3) is a tyrosine kinase that is expressed on the lymphatic endothelium and that signals for the growth of the lymphatic vessels (lymphangiogenesis). Vegf-d, a secreted glycoprotein, is one of two known activating ligands for Vegfr-3, the other being Vegf-c. Vegf-d stimulates lymphangiogenesis in tissues and tumors; however, its role in embryonic development was previously unknown. Here we report the generation and analysis of mutant mice deficient for Vegf-d. Vegf-d-deficient mice were healthy and fertile, had normal body mass, and displayed no pathologic changes consistent with a defect in lymphatic function. The lungs, sites of strong Vegf-d gene expression during embryogenesis in wild-type mice, were normal in Vegf-d-deficient mice with respect to tissue mass and morphology, except that the abundance of the lymphatics adjacent to bronchioles was slightly reduced. Dye uptake experiments indicated that large lymphatics under the skin were present in normal locations and were functional. Smaller dermal lymphatics were similar in number, location, and function to those in wild-type controls. The lack of a profound lymphatic phenotype in Vegf-d-deficient mice suggests that Vegf-d does not play a major role in lymphatic development or that Vegf-c or another...

‣ Smad1 and Smad8 Function Similarly in Mammalian Central Nervous System Development

Hester, Mark; Thompson, John C.; Mills, Joseph; Liu, Ye; El-Hodiri, Heithem M.; Weinstein, Michael
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /06/2005 Português
Relevância na Pesquisa
36.691194%
Smads 1, 5, and 8 are the intracellular mediators for the bone morphogenetic proteins (BMPs), which play crucial roles during mammalian development. Previous research has shown that Smad1 is important in the formation of the allantois, while Smad5 has been shown to be critical in the process of angiogenesis. To further analyze the BMP-responsive Smads, we disrupted the murine Smad8 gene utilizing the Cre/loxP system. A Smad8 hypomorphic allele (Smad8Δexon3) was constructed that contains an in-frame deletion of exon 3, removing one-third of the MH2 domain and a small portion of the linker region. Xenopus injection assays indicated that this Smad8 deletion allele is still functional but has reduced ventralizing capability compared to the wild type. Although Smad8Δexon3/Δexon3 embryos are phenotypically normal, homozygotes of another hypomorphic allele of Smad8 (Smad83loxP) containing a neomycin cassette within intron 3, phenocopy an embryonic brain defect observed in roughly 22% of Smad1+/− embryos analyzed at embryonic day 11.5. These observations suggest that BMP-responsive Smads have critical functions in the development of the mammalian central nervous system.

‣ Perturbation of the Hematopoietic System during Embryonic Liver Development Due to Disruption of Polyubiquitin Gene Ubc in Mice

Ryu, Kwon-Yul; Park, Hyejin; Weissman, Irving L.; Rossi, Derrick J; Kopito, Ron R.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.61457%
Disruption of the polyubiquitin gene Ubc leads to a defect in fetal liver development, which can be partially rescued by increasing the amount of ubiquitin. However, it is still not known why Ubc is required for fetal liver development and the nature of the defective cell types responsible for embryonic lethality have not been characterized. In this study, we assessed the cause of embryonic lethality with respect to the fetal liver hematopoietic system. We found that Ubc was highly expressed in the embryonic liver, and the proliferation capacity of fetal liver cells was reduced in Ubc(^{−/−}) embryos. Specifically, Ubc was most highly expressed in hematopoietic cells, and the proliferation capacity of hematopoietic cells was significantly impaired in Ubc(^{−/−}) embryos. While hematopoietic cell and hematopoietic stem cell (HSC) frequency was maintained in Ubc(^{−/−}) embryos, the absolute number of these cells was diminished because of reduced total liver cell number in Ubc(^{−/−}) embryos. Transplantations of fetal liver cells into lethally irradiated recipient mice by non-competitive and competitive reconstitution methods indicated that disruption of Ubc does not significantly impair the intrinsic function of fetal liver HSCs. These findings suggest that disruption of Ubc reduces the absolute number of HSCs in embryonic livers...

‣ Network Similarity Measures and Automatic Construction of Graph Models using Genetic Programming

Harrison, Kyle Robert
Fonte: Brock University Publicador: Brock University
Tipo: Electronic Thesis or Dissertation
Português
Relevância na Pesquisa
37.143079%
A complex network is an abstract representation of an intricate system of interrelated elements where the patterns of connection hold significant meaning. One particular complex network is a social network whereby the vertices represent people and edges denote their daily interactions. Understanding social network dynamics can be vital to the mitigation of disease spread as these networks model the interactions, and thus avenues of spread, between individuals. To better understand complex networks, algorithms which generate graphs exhibiting observed properties of real-world networks, known as graph models, are often constructed. While various efforts to aid with the construction of graph models have been proposed using statistical and probabilistic methods, genetic programming (GP) has only recently been considered. However, determining that a graph model of a complex network accurately describes the target network(s) is not a trivial task as the graph models are often stochastic in nature and the notion of similarity is dependent upon the expected behavior of the network. This thesis examines a number of well-known network properties to determine which measures best allowed networks generated by different graph models, and thus the models themselves...

‣ Object-Oriented Genetic Programming for the Automatic Inference of Graph Models for Complex Networks

Medland, Michael; Medland, Michael
Fonte: Brock University Publicador: Brock University
Tipo: Electronic Thesis or Dissertation
Português
Relevância na Pesquisa
37.159814%
Complex networks are systems of entities that are interconnected through meaningful relationships. The result of the relations between entities forms a structure that has a statistical complexity that is not formed by random chance. In the study of complex networks, many graph models have been proposed to model the behaviours observed. However, constructing graph models manually is tedious and problematic. Many of the models proposed in the literature have been cited as having inaccuracies with respect to the complex networks they represent. However, recently, an approach that automates the inference of graph models was proposed by Bailey [10] The proposed methodology employs genetic programming (GP) to produce graph models that approximate various properties of an exemplary graph of a targeted complex network. However, there is a great deal already known about complex networks, in general, and often specific knowledge is held about the network being modelled. The knowledge, albeit incomplete, is important in constructing a graph model. However it is difficult to incorporate such knowledge using existing GP techniques. Thus, this thesis proposes a novel GP system which can incorporate incomplete expert knowledge that assists in the evolution of a graph model. Inspired by existing graph models...

‣ Risk of death among cases attending South Australian major trauma services after severe trauma: the first 4 years of operation of a state trauma system

Brennan, P.; Everest, E.; Griggs, W.; Slater, A.; Carter, L.; Lee, C.; Semmens, J.; Wood, D.; Nguyen, A.M.; Owen, D.; Pilkington, P.; Roder, D.; Somers, R.
Fonte: Lippincott Williams & Wilkins Publicador: Lippincott Williams & Wilkins
Tipo: Artigo de Revista Científica
Publicado em //2002 Português
Relevância na Pesquisa
36.84317%
BACKGROUND: Factors predictive of death at South Australian major trauma services were investigated among 8,654 patients who had experienced severe trauma from 1997 to 2000. METHOD: Univariate and multivariate analyses of age, sex, injury severity, presence of comorbid conditions, and calendar year of presentation were performed. RESULTS: Multiple logistic regression indicated that factors predictive of death were older age; higher injury severity as indicated by the New Injury Severity Score and the Revised Trauma Score; and accompanying chronic liver disease, ischemic heart disease, and chronic renal failure. A decrease in risk of death by calendar year was statistically significant (p = 0.001). Using 1997 as the reference, the relative odds of death were 0.86 (95% confidence limits) (0.53, 1.39) for 1998, 0.60 (0.36, 0.99) for 1999, and 0.45 (0.27, 0.76) for 2000. CONCLUSION: Results show a decrease in risk of death of patients attending South Australian major trauma services, from injuries of equivalent severity, during the first 4 years of operation of the State Trauma System.; Brennan, Peter W ; Everest, Evan R ; Griggs, William M ; Slater, Anthony ; Carter, Libby ; Lee, Christine ; Semmens, Julie K ; Wood, Debra J ; Nguyen, Anh-minh T ; Owen...

‣ New types of knowledge about system dynamics for intelligent control system design.

Mohammadzaheri, Morteza
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2011 Português
Relevância na Pesquisa
36.835422%
This is a thesis by publication. This thesis comprises ten published/submitted journal articles including eight research articles and two review articles. Five of these journal papers have been already published or finally accepted for publication. This thesis, based on research undertaken in the area of intelligent and non-model-based control, aims at broadening knowledge about system dynamics applicable for control system design. Currently, mathematical models of systems, experimental input-output data and experts’ knowledge in the form of fuzzy rules (linguistic expressions) are three types of knowledge about systems dynamics which are employed in control system design. These types of knowledge are used to define the number and the positions of controllers in the control system (architecture of control systems) and/or the mathematical form of controllers (controllers’ structure) and/or controllers’ parameters. Defining control systems at these three levels (architecture, controllers’ structure and parameters) forms the process of control design. In the area of non-model-based control, some cases of unexpected poor control performance were observed by the author. For instance, neuro-predictive method controls process plants very well. This method is based on input-output data. Thus...

‣ Untersuchung zur Translokation von "Yersinia outer proteins" in Wirtszellen mit Hilfe des YopE-Cre Reportersystems; Analysis of translocation of "ersinia outer proteins" into host cells viaYopE-Cre reporter system

Kovacevic, Sandra
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
Português
Relevância na Pesquisa
37.10511%
Humanpathogene Yersinien unterlaufen die angeborene Immunabwehr des Wirtes, indem sie eine Gruppe von Virulenzfaktoren, die sogenannten Yersinia outer proteins (Yop) E, T, H, M, O und P mittels eines Typ III Sekretionssystems (TTSS) direkt in Wirtszellen translozieren. Diese Yops inhibieren Wirtszellfunktionen und nehmen so negativen Einfluss auf die Immunabwehr. In diversen Studien wurden zum besseren Verständnis, wie die Yop Translokation durch das TTSS von Yersinien funktioniert, verschiedene Reportersysteme entwickelt. Ziel der vorliegenden Arbeit war es ein Reportersystem, basierend auf einem Cre YopE Fusionsprotein und lox P flankiertem Reportergenkonstrukt zu entwickeln, um in Infektionsexperimenten zunächst von kultivierten Zellen diejenigen Zellen zu erkennen, in die die Yops transloziert werden. Langfristig sollte dieses System dazu dienen, Yop Translokation im Mausinfektionsmodell nachzuweisen. Das Prinzip des Systems ist es, einen Yersinien Stamm zu generieren, der nach Kontakt mit Zellen ein YopE Cre Fusionsprotein in die Zelle injiziert. Die translozierte Cre Rekombinase deletiert dann ein Genfragment, so dass ein konstitutiv aktiver Promotorbereich in die Nähe eines für Beta-Galaktosidase kodierenden Genabschnitts gebracht wird. Nach Expression von Beta-Galaktosidase kann diese durch Färbung mit X-Gal...

‣ International Reference Life Cycle Data System (ILCD) Handbook: Framework and Requirements for Life Cycle Impact Assessment Models and Indicators

NOT INDICATED .
Fonte: Publications Office of the European Union Publicador: Publications Office of the European Union
Tipo: EUR - Scientific and Technical Research Reports Formato: Online
Português
Relevância na Pesquisa
36.977373%
Life Cycle Thinking (LCT) and Life Cycle Assessment (LCA) are scientific approaches behind a growing number of modern environmental policies and business decision support in the context of Sustainable Consumption and Production (SCP). The International Reference Life Cycle Data System (ILCD) provides a common basis for consistent, robust and quality-assured life cycle data, methods and assessments. These support coherent and reliable business and policy instruments related to products, natural resources, and waste management and their implementation, such as eco-labelling, carbon footprinting, and, green procurement. This guidance document provides a framework and requirements for the models that are used to analyse the emissions into air, water and soil, as well as the resources consumed in terms of their contributions to different impacts on human health, natural environment, and natural resources. In a Life Cycle Assessment, the emissions and resources consumed that are linked to a specific product are compiled and documented in a Life Cycle Inventory (LCI). An impact assessment is then performed, considering human health, the natural environment, and issues related to natural resource use. Impacts considered in a Life Cycle Impact Assessment include climate change...

‣ System Usability and User Mental Models of Three Verifiable, End-to-end Voting Methods: Helios, Prêt à Voter, and Scantegrity II

Acemyan, Claudia Ziegler
Fonte: Universidade Rice Publicador: Universidade Rice
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
37.214966%
There are many ways voting systems can be maliciously attacked so that election outcomes are altered. In response, voting security experts developed end-to-end (e2e), verifiable voting methods. These systems were intended to be secure, accurate, reliable, and transparent, while still preserving voter anonymity. What is not clear is if these complex, novel systems, which allow voters to check on their ballots after voting, will be usable by every voter. If voting methods are unusable, negative ramifications like disenfranchisement and altered election outcomes could occur. For this reason, system usability and voter mental models of e2e systems must be understood. To address this lacuna in voting research, three e2e methods representative of voter verifiable technologies were studied: Helios, Prêt à Voter, and Scantegrity II. Four studies were conducted. In the first study, baseline usability data was collected. By having participants vote with each system in a mock election, it was found that the systems were difficult, if not impossible, to use. Only 58% of voters were able to cast a ballot, and fewer were able to verify their vote. In the second study, the behavioral errors that led to ballot casting and vote verification event failures were identified...

‣ A guideline for initiating an environmental management system in academia

Turkow, David
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
36.738345%
Managing environmental concerns in an academic environment poses unique challenges to colleges and universities. Many college EHS professionals face an uphill battle to promote environmental improvement in an organized, systematic, and sustainable fashion - an Environmental Management System (EMS) is designed to do just that. Some inherent difficulties encountered in an academic setting include 1) lack of management support and 2) the perception that colleges do not have major environmental compliance issues (contributing factor to #1). By identifying issues unique to academia and differences in perception between EHS professionals and academic senior management, chances for successfully initiating/implementing an EMS are improved. Environmental Management Systems (EMSs) are being promoted as the method to effectively manage environmental issues on college campuses in the US. The Environmental Protection Agency (EPA) has made it clear that they expect colleges and universities to maintain compliance with environmental regulations and they feel an EMS is the preferred method for long-term, sustainable environmental compliance. Although there are several guidelines/models (see references & attachment #2 ) for implementing an EMS, many colleges never make it to the planning stage of an EMS. There is no guideline for "getting an EMS off the ground" - or...

‣ Verification Analysis Of Lake Ontario And Rochester Embayment Three Dimensional Euthophication Models

Thomann, Robert V.; Winfield, Richard P.; Segna, John J.
Fonte: Universidade de Delaware Publicador: Universidade de Delaware
Tipo: Relatório Formato: 6640939 bytes; application/pdf
Português
Relevância na Pesquisa
37.059692%
A three dimensional time variable model of the phytoplankton and nutrients of Lake Ontario and the Rochester Embayment is examined in detail. The data from the International Field Year on the Great Lakes (IFYGL) are used as the primary data base. The data are summarized and statistically analyzed on a three dimensional grid and segment averages using a 67 segment representation of the lake and a 72 segment representation of Rochester Embayment, are calculated. In addition, averages for eight regions of the lake and lake wide averages for two depth layers are computed. Average phytoplankton levels during the period May, 1972 and June, 1973 in the near shore region are approximately 3 ug/l higher than open lake values. Similarly, near shore open lake total phosphorus gradients of about 5 ug P/L appear to persist for a substantial part of the year. The data base collected during IFYGL exhibited significant spatial and temporal variations at scales of 10 x 40 km. The two data bases available, Canadian Centre for Inland Waters (CCIW) and Environmental Protection Agency (EPA), only agree within certain limits. The verification analysis of the models indicates that the median relative error for the results of calculated versus observed chlorophyll on the segment to segment level is about 30%. The inclusion of diatoms and nondiatoms and silica limitation in the kinetic structure...

‣ Modelling of peripheral lymphocyte migration: system identification approach

Srikusalanukul, Wichat; De Bruyne, Franky; McCullagh, Peter
Fonte: Blackwell Publishing Ltd Publicador: Blackwell Publishing Ltd
Tipo: Artigo de Revista Científica
Português
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This is the first application of the prediction error method (PEM) of system identification to modelling lymphocyte migration through peripheral lymphoid tissue. The PEM was applied to the emergence of labelled lymphocytes from the efferent lymphatic of a lymph node following their intravenous administration. Advantages of PEM included the capacity to calculate the response to a unit impulse stimulus, unavailable to direct observation, and to allow for the return to the node of labelled cells that had already recirculated once. Calculation of the system delay (time between introduction of cells into the blood and their first appearance in lymph) indicated 4.67 ± 1.05 h for the total lymphocyte population. The peak in efferent lymph occurred at 11.91 ± 4.68 h, much earlier than previous reports, which were affected by cells that had already recirculated. While 75% of labelled cells had emerged in efferent lymph by 20.77 ± 5.62 h, 86.38 ± 29.44 h was required for 100% emergence. The considerable heterogeneity in migratory behaviour is likely to reflect frequency and duration of binding of lymphocytes by dendritic cells in paracortical cord corridors. It is proposed that differences in the speed with which lymphocytes pass along corridors depend on their functional status...