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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.
61

Transportation risk assessment for ethanol transport

Shelton Davis, Anecia Delaine 15 May 2009 (has links)
This research is aimed at assessing the quantitative risks involved with an ethanol pipeline. Pipelines that run from the Midwest, where the vast majority of ethanol is produced, to the target areas where reformulated gasoline is required (California, Texas Gulf Coast, New England Atlantic Coast) will be of particular interest. The goal is to conduct a quantitative risk assessment on the pipeline, truck, and rail transportation modes to these areas. As a result of the quantitative risk assessment, we are able to compare the risk associated with the different modes of transportation for ethanol. In order to perform and compare the quantitative risk assessment, the following challenges are addressed: • Identify target areas requiring reformulated gasoline • Map detailed route for each transportation mode to all three target areas • Perform a quantitative risk assessment for each transportation mode • Compare quantitative risk assessment results for each route and transportation mode The focus is on California, Texas Gulf Coast, and New England Atlantic Coast because of the large volume. It is beneficial to look at these areas as opposed to the smaller areas because pipeline transportation requires very large volumes. In order to find a meaningful comparison between all three transportation modes, only the areas with the three large volumes were evaluated. Since the risk assessment is completed using historical data, each route is segmented in a way that is consistent with the data that is available. All of the curves support the hypothesis that pipeline transportation poses the least societal risk when transporting ethanol from the Midwest to target areas. Rail transportation poses the largest amount of societal risk. While overall rail incidents are not as frequent as road incidents, the frequency of a fatality is much higher when an incident does occur.
62

Transportation risk assessment for ethanol transport

Shelton Davis, Anecia Delaine 10 October 2008 (has links)
This research is aimed at assessing the quantitative risks involved with an ethanol pipeline. Pipelines that run from the Midwest, where the vast majority of ethanol is produced, to the target areas where reformulated gasoline is required (California, Texas Gulf Coast, New England Atlantic Coast) will be of particular interest. The goal is to conduct a quantitative risk assessment on the pipeline, truck, and rail transportation modes to these areas. As a result of the quantitative risk assessment, we are able to compare the risk associated with the different modes of transportation for ethanol. In order to perform and compare the quantitative risk assessment, the following challenges are addressed: 1) Identify target areas requiring reformulated gasoline 2) Map detailed route for each transportation mode to all three target areas 3) Perform a quantitative risk assessment for each transportation mode 4) Compare quantitative risk assessment results for each route and transportation mode The focus is on California, Texas Gulf Coast, and New England Atlantic Coast because of the large volume. It is beneficial to look at these areas as opposed to the smaller areas because pipeline transportation requires very large volumes. In order to find a meaningful comparison between all three transportation modes, only the areas with the three large volumes were evaluated. Since the risk assessment is completed using historical data, each route is segmented in a way that is consistent with the data that is available. All of the curves support the hypothesis that pipeline transportation poses the least societal risk when transporting ethanol from the Midwest to target areas. Rail transportation poses the largest amount of societal risk. While overall rail incidents are not as frequent as road incidents, the frequency of a fatality is much higher when an incident does occur.
63

Understanding and modeling ecological processes controlling flammability in seasonally dry evergreen forests of the Brazillian Amazon /

Negreiros, Gustavo Hees de. January 2004 (has links)
Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 152-159).
64

Evaluation of risks to human health in Hong Kong from consumption of chemically contaminated seafood : a risk assessment approach /

Shaw, Brenda Jo. January 1995 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1995. / Includes bibliographical references.
65

Social process of environmental risk perception, preferences of risk management and public participation in decision making a cross-cultural study between the United States and China /

Duan, Hongxia, January 2005 (has links)
Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Includes bibliographical references (p. 198-214).
66

A methodology for quantitative ecological risk assessment for industrial accidents

DUARTE, Heitor de Oliveira 31 January 2011 (has links)
Made available in DSpace on 2014-06-12T17:42:48Z (GMT). No. of bitstreams: 2 arquivo7684_1.pdf: 3197582 bytes, checksum: e9a5a1df323907fb05bb3c1b206c2fd5 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2011 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Recentes acidentes industriais, como vazamentos tóxicos, têm causado danos catastróficos ao meio ecológico (i.e. plantas e animais), de modo que um método efetivo para analisar riscos ecológicos tem sido demandado. Em primeiro lugar, este trabalho tem como objetivo propor uma metodologia capaz de quantificar riscos ecológicos inerentes a eventos raros como acidentes industriais. Utiliza-se a modelagem populacional para simular futuras mudanças na abundância populacional de espécies-chave em risco e, assim, estimar a probabilidade de extinção ou declínio, tempo para extinção e outras medidas, para cada cenário acidental. Assim, foi possível desenvolver uma abordagem que combina os danos ecológicos (previstos através da modelagem populacional) com a frequência de ocorrência do cenário acidental (estimada através de dados históricos e análise de confiabilidade). O resultado é uma curva de risco FN (similar ao resultado de uma análise de risco a humanos), onde N é o declínio populacional médio e F a frequência acumulada de acidentes com declínio maior ou igual a N. Em segundo lugar, o trabalho apresenta uma aplicação da metodologia para quantificar os riscos ecológicos provenientes de acidentes associados ao transporte e manuseio de petróleo que abastece uma refinaria no Complexo Industrial Portuário de Suape-PE, no Nordeste do Brasil. Esta instalação está localizada próxima a um rico ecossistema aquático de alta biodiversidade. A população de uma espécie nativa foi estrategicamente escolhida para representar o ecossistema, alguns cenários de derramamento de petróleo foram simulados e suas frequências de ocorrência estimadas. Para cada cenário acidental, a concentração de óleo que atinge a população foi prevista via modelagem de destino e transporte. Os riscos ecológicos foram quantificados e apresentados em uma curva FN. Uma análise de sensibilidade foi feita para explorar como mudanças em parâmetros específicos causam mudanças nas medidas de risco. Além disso, a incerteza foi medida como um intervalo (limite superior e inferior) para as medidas de riscos com base em cenários pessimistas e otimistas. Finalmente, a metodologia mostrou-se viável, eficiente, conveniente e flexível, apesar de que algumas melhorias ainda podem ser feitas e estas foram propostas para trabalhos futuros
67

Engineering approach to risk management in information technology systems

Seker, Harun 10 September 2012 (has links)
M.Phil. / The use of information systems has increased dramatically after the emergence of internet. Individuals, companies and organizations are becoming increasingly dependent on IT systems. Before technology and computers became such an important part of society, it was difficult to manage and control large organizations. Today computers enable the effective and efficient management of large organizations, therefore allowing them to spread throughout the country and world. Businesses are following latest advances in this era to remain competitive in the changing global market place. They use computers, automated IT systems and networks to gather, store, retrieve, process, and analyze information as well as to trade and communicate. The rapid advances in computer technology are largely a result of the research, development and design efforts of computer engineers. There is a direct correlation between a nation's wealth and scientific and technological capacity. The most effective way of taking our country forward is to enthuse our youth for science and technology. As the world makes rapid, sometimes breathtaking strides in the diverse fields of science and technology, South Africa more than ever needs qualified individuals who will use their skills and entrepreneurial spirit to enable our country to complete internationally with the best. However, Information systems and networks and their worldwide increasing usage have been accompanied by new and increasing risks. Data and information stored on and transmitted over information technology systems and networks are subject to threats from various means of unauthorized access, such as misuse, misappropriation, alteration, malicious code transmissions, denial of service or destruction and require appropriate safeguards. This research report will aim to emphasize the importance of risk management and its three activities; risk assessment, risk mitigation and evaluation and assessment. It will focus on activities that deal with the solution of problems through logical thinking, information system management This report will also deal with a case study that gives us real life examples of risk management experiences of one local computer hardware and software supplier companies. Information has become valuable assets that need to be protected after moving to a digital era and E-commerce. Protecting information can also be as critical as protecting other resources like money and physical assets.
68

An investigation of risk homeostasis in a laboratory environment

Marshall, Rafael 17 March 2010 (has links)
This study investigated whether risk compensation behavior would occur during a chemistry experiment due to the presence of protective equipment. This study also examined whether a homeostatic regulating mechanism exists for risk-taking behavior. Risk compensation and a homeostatic regulating mechanism for risk-taking behavior are both encompassed within the Risk Homeostasis Theory, which states that people accurately perceive and fully compensate for changes in risk. Thirty-six subjects performed three trials of a short chemistry experiment either with protective equipment or without protective equipment during the first of two sessions. After the first session, half the subjects were required to switch from wearing protective equipment to not wearing protective equipment, or from not wearing protective equipment to wearing protective equipment. The time required to complete the task, the number of errors committed, and subtask measurement accuracy were tabulated. Between-subject analyses did not reveal risk compensation behavior. Moreover, within-subject comparisons failed to show a significant risk compensation effect or the presence of a homeostatic regulating mechanism for risk-taking behavior. The results suggested that the Risk Homeostasis Theory may not explain sufficiently changes in behavior due to increases (or decreases) in perceived risk. The limitations of the present study were discussed. Suggestions and examples for research on different aspects of the Risk Homeostasis Theory were also provided. / Master of Science
69

An analysis of 'Bid-Ask' spreads considering aspects of risk insurance, degree of competition and market liquidity

Gerber-Helbling, Silvia A. January 1994 (has links)
No description available.
70

A study of decision-making about risk of violence in mentally disordered offenders

Cohen, Andrea January 2000 (has links)
No description available.

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