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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.
51

Pojištění environmentálních rizik / Environmental risks insurance

Horníčková, Lenka January 2011 (has links)
The thesis focuses on environmental liability insurance as a representative of various methods of financial guarantee with respect to the environmental damage risk. The environmental risk is explained in the context of the theory of insurance and the specific features of this risk, which may lead to a discussion about insurability of environmental damage risk, are pointed out. The thesis is also aimed at the legal rules in the Czech republic, because there is a close relationship between the environmental insurance and existing legal rules. Last but not least, the thesis also provides an overview of the environmental insurance products available in the Czech republic.
52

Avaliação de risco ambiental em solos brasileiros de um herbicida em desenvolvimento para campos de cereais / Environmental risk assessment in Brazilian soils of a herbicide under development for cereal fields

Otavio Balderrama Pinto 17 September 2010 (has links)
Um novo herbicida da classe das sulfonamida-triazolopirimidinas do grupo dos herbicidas inibidores da síntese do acetolactato (ALS) encontra-se em desenvolvimento. Trata-se de um herbicida ionizável, com caráter ácido fraco (pKa = 4,67). Sua solubilidade em água depende do pH do meio, trata-se de uma molécula hidroliticamente estável, sendo bastante suscetível à fotodegradação em meio aquoso. A fotodegradação em solo não é significativa. Neste estudo, avaliaram-se os potenciais de sorção, lixiviação e dissipação deste herbicida em quatro solos brasileiros: Gleissolo Melânico Alumínico típico (GMa), Latossolo Vermelho Distroférrico típico (LVdf), Neossolo Quartzarênico órtico típico (RQ) e Argissolo Vermelho eutroférrico chernossólico (PV). No estudo de sorção, as isotermas foram ajustadas através do modelo de Freundlich e os valores dos coeficientes de sorção (Kd) variaram de 0,5 a 22,4 mL g-1 indicando um potencial de sorção baixo a moderado. No estudo de mobilidade, nenhuma radioatividade foi observada nos lixiviados coletados até 48 horas nos solos GMa, LVdf e PV, no solo RQ detectou-se 2 % do aplicado. Os resultados de mobilidade comparativos sugerem que o herbicida seja classificado como moderadamente móvel pelo critério do Fator de Mobilidade Relativa (FMR) em todos os solos estudados. No estudo de dissipação, a taxa de transformação do herbicida em condições aeróbicas além da natureza e taxa de formação e declínio de produtos de transformação do herbicida foram acessados. Um modelo exponencial de primeira ordem foi utilizado para ajustar a dissipação do herbicida nos solos. A meia-vida do herbicida foi de 22, 15, 110 e 39 nos solos GMa, LVdf, RQ e PV, respectivamente. Uma avaliação de risco ambiental inicial do herbicida foi acessada pelo uso do método dos quocientes (RQ risk quotient), sendo risco = exposição/efeito. A exposição é representada pela Concentração Ambiental Esperada (CAE) e foi avaliada nos compartimentos ambientais solo, águas superficiais e águas subterrâneas. Os cálculos de CAE foram obtidos por avaliação de cenários simples do tipo pior caso nos diferentes compartimentos e pelo emprego dos modelos matemáticos GENEEC e SCIGROW para águas superficiais e subterrâneas, respectivamente. Na estimativa do efeito, usou-se os valores limite (endponts, exemplos: EC50, NOEC) disponíveis para diferentes organismos representantes dos diferentes compartimentos ambientais estudados. O resultado do quociente exposição/efeito foi comparado com os níveis de preocupação (LOC level of concern) empregados pelo EPA para avaliação do potencial risco do uso deste herbicida para os diferentes organismos representativos dos diferentes compartimentos ambientais estudados. Assumindo o pior cenário (menor valor de Kd e maior valor de DT50), as estimativas das CAEs foram baixas e iguais a 0,024 mg kg-1 no solo, a 0,0008 mg L-1 na água superficial e a 0,04 \'mü\' L-1 na água subterrânea. Os valores de RQ obtidos (< 1 e inferiores aos respectivos LOCs) indicaram baixo potencial de risco do uso deste herbicida para os diferentes organismos, representativos dos diversos compartimentos ambientais estudados / A new active ingredient of the triazolopyrimidine sulfonamide herbicide class from the ALS group is under development. This is an ionizable herbicide with weakly acidic behavior (pKa = 4.67). Its solubility in water depends on pH, it is a hydrolytically stable molecule, being highly susceptible to photodegradation in aqueous medium. The photodegradation in soil is not significant. This study evaluated the potential of sorption, leaching and dissipation of this herbicide in four Brazilian soils: Gleissolo Melânico Alumínico típico (GMa), Latossolo Vermelho Distroférrico típico (LVdf), Neossolo Quartzarênico órtico típico (RQ) e Argissolo Vermelho eutroférrico chernossólico (PV). In the study of sorption isotherms were fitted using the Freundlich model and the values of sorption coefficients (Kd) ranged from 0.5 to 22.4 g mL-1 indicating a potential low to moderate sorption. In the study of mobility, no radioactivity was observed in the leachate collected until 48 hours in soils GMa, LVdf and PV, in the soil RQ was detected about 2% of applied radioactivity. The results of comparative mobility suggest that the herbicide is classified as moderately mobile by the criterion of Relative Mobility Factor (FMR) in all soils. In the study of dissipation, the rate of transformation of the herbicide under aerobic conditions and rate of formation and decline of transformation products of herbicide were accessed. A first order exponential model was used to adjust the dissipation of the herbicide in soils. The half-life of the herbicide was 22, 15, 110 and 39 days in soils GMa, LVdf, RQ and PV, respectively. An initial environmental risk assessment of the herbicide was accessed by using the method of quotient (RQ - risk quotient), RQ = exposure / effect. The exposure is represented by the Expected Environmental Concentration (EEC) and was evaluated in the environmental compartments soil, surface water and groundwater. EEC calculations were obtained by assessing simple scenarios such as \"worst case\" in the different compartments and the use of mathematical models GENEEC and SCIGROW to surface and groundwater assessments, respectively. In estimating the effect, endponts (examples: EC50, NOEC) available for different organisms representative from the different environmental compartments studied were used. The result of the quotient exposure / effect was compared to the \"levels of concern (LOC - level of concern) employed by the EPA to assess the potential risk from use of this herbicide for different organisms representing different environmental compartments studied. Assuming the worst case scenario (lower Kd value and higher value of DT50), the estimates of EECs were low and equal to 0.024 mg kg-1 soil, 0.0008 mg L-1 in surface water and 0.04 \'mü\' L-1 in the groundwater. The RQ values obtained (< 1 and below the respective LOCs) indicated low potential risk from use of this herbicide for different organisms, representative from different environmental compartments studied
53

Ensaios ecotoxicol?gicos como ferramenta para avalia??o do impacto ambiental de res?duos de minera??o sobre o solo / Ecotoxicological assays as a tool for environmental impact assessment of mining waste on soil

BIANCHI, Miriam de Oliveira 27 February 2013 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-08-29T17:27:52Z No. of bitstreams: 1 2013 - Miriam de Oliveira Bianchi.pdf: 4091539 bytes, checksum: 098efb42e3013339939d9ac91d1c741c (MD5) / Made available in DSpace on 2017-08-29T17:27:52Z (GMT). No. of bitstreams: 1 2013 - Miriam de Oliveira Bianchi.pdf: 4091539 bytes, checksum: 098efb42e3013339939d9ac91d1c741c (MD5) Previous issue date: 2013-02-27 / CAPES / The studies were carried part of the University of Coimbra - Portugal (Ecotoxicology Laboratory of Soil and Marine Research Institute-IMAR) and part of the premises of Embrapa Agrobiology - RJ. Originated from the beneficiation process aluminum, red mud (red mud), is generated from the refining of bauxite to produce alumina (Al2O3). Characterized as material of high alkalinity and large amount of salts associated with a huge amount produced annually by industries, the disposal of this material requires innumerous care. Accordingly, studies involving the analysis of the possible effects of the use and application of this material in the soil and on water sources emerge as key tools to minimize damage, either to the soil biological community, as water bodies. The aim of this study were assessing the intrinsic toxicity of red mud in soil organisms in artificial soil (Chapter I), and In Natural soil (Chapter II); end on aquatic organisms (Chapter III) as a result of leaching from contaminated soil solution. For ecotoxicological tests with soil organisms we studied two 'types' of waste, namely the red mud ?In Natura? and "Filtered" (with a 3% reduction in the content of Na). The concentrations tested were initially 0, 10, 20, 30, 40, 50, 60, 70, 80 and 90% of the residue ?In Natura?, and then set new doses of 0, 2.5, 5, 10, 20, 30 and 40% residual In Natura and also the "Filtered", and two types of soil collected in the same region (Po?os de Caldas - MG) where there are deposits of bauxite (Alcoa). In Chapter a considerable difference in the sensitivity of the test organisms was checked. The results showed that the red mud strongly inhibited reproduction for each. The high sodium concentration (Na+ = 18500.9 mg L-1) is probably the most deleterious factor for the reproduction of these species and has not been minimized toxicity by treatment applied to the sludge to reduce this salt. In Chapter II was observed an increase in the effects of the toxicity associated with natural soils. Still, the particular characteristics of each soil allow achieving particular outcomes for each environment tested. In Chapter III the residue ?In Natura? proved toxic to all aquatic organisms studied. / Os estudos foram realizados parte na Universidade de Coimbra ? Portugal (Laborat?rio de Ecotoxicologia de Solos e Instituto de Pesquisas Marinhas-IMAR) e parte nas instala??es da Embrapa Agrobiologia ? RJ. Originada do processo de beneficiamento do alum?nio, a lama vermelha (lama vermelha), ? gerada a partir do refino da bauxita para produ??o de alumina (Al2O3). Caracterizada como material de alta alcalinidade e grande quantidade de sais, associado ? grande quantidade produzida anualmente pelas ind?strias, o descarte desse material necessita de in?meros cuidados. Nesse sentido, estudos que envolvam a an?lise dos poss?veis efeitos da utiliza??o e aplica??o desse material tanto no solo como sobre as fontes de ?gua surgem como ferramentas fundamentais para minimizar danos, seja para a comunidade biol?gica do solo, como de corpos h?dricos. Os objetivos deste estudo foram avaliar a toxicidade intr?nseca da lama vermelha sobre organismos em solo artificial (Cap?tulo I); e em solos naturais (Cap?tulo II); e sobre organismos aqu?ticos (Cap?tulo III) em consequ?ncia da lixivia??o da solu??o do solo contaminado. Para os ensaios ecotoxicol?gicos com organismos de solo foram estudados dois ?tipos? do res?duo, a saber, a lama vermelha ?In Natura? e ?Filtrado? (com redu??o de 3% no teor de Na). As concentra??es ensaiadas foram inicialmente 0, 10, 20, 30, 40, 50, 60, 70, 80 e 90% do res?duo ?In Natura?, e em seguida, definidas novas doses de 0, 2,5, 5, 10, 20, 30 e 40% de res?duo ?In Natura? e tamb?m do ?Filtrado?, al?m de dois tipos de solo coletados na mesma regi?o (Po?os de Caldas - MG) onde ocorrem jazidas de bauxita. No Cap?tulo I foi verificada uma consider?vel diferen?a na sensibilidade dos organismos testados. Os resultados demonstraram que a lama vermelha inibiu fortemente a reprodu??o para cada um deles. O alto teor de s?dio (Na+ = 18500,9 mg L-1) ? provavelmente o fator mais delet?rio para a reprodu??o dessas esp?cies, n?o tendo sido minimizada a toxicidade pelo tratamento aplicado ? lama para a redu??o desse sal. No cap?tulo II foi poss?vel observar um incremento dos efeitos dessa toxicidade quando associado a solos naturais. Ainda assim, caracter?sticas particulares de cada solo permitem alcan?ar resultados particulares para cada ambiente testado. No Cap?tulo III o res?duo ?In Natura? mostrou-se t?xico para todos os organismos aqu?ticos estudados.
54

Avaliação de risco ambiental em solos brasileiros de um herbicida em desenvolvimento para campos de cereais / Environmental risk assessment in Brazilian soils of a herbicide under development for cereal fields

Pinto, Otavio Balderrama 17 September 2010 (has links)
Um novo herbicida da classe das sulfonamida-triazolopirimidinas do grupo dos herbicidas inibidores da síntese do acetolactato (ALS) encontra-se em desenvolvimento. Trata-se de um herbicida ionizável, com caráter ácido fraco (pKa = 4,67). Sua solubilidade em água depende do pH do meio, trata-se de uma molécula hidroliticamente estável, sendo bastante suscetível à fotodegradação em meio aquoso. A fotodegradação em solo não é significativa. Neste estudo, avaliaram-se os potenciais de sorção, lixiviação e dissipação deste herbicida em quatro solos brasileiros: Gleissolo Melânico Alumínico típico (GMa), Latossolo Vermelho Distroférrico típico (LVdf), Neossolo Quartzarênico órtico típico (RQ) e Argissolo Vermelho eutroférrico chernossólico (PV). No estudo de sorção, as isotermas foram ajustadas através do modelo de Freundlich e os valores dos coeficientes de sorção (Kd) variaram de 0,5 a 22,4 mL g-1 indicando um potencial de sorção baixo a moderado. No estudo de mobilidade, nenhuma radioatividade foi observada nos lixiviados coletados até 48 horas nos solos GMa, LVdf e PV, no solo RQ detectou-se 2 % do aplicado. Os resultados de mobilidade comparativos sugerem que o herbicida seja classificado como moderadamente móvel pelo critério do Fator de Mobilidade Relativa (FMR) em todos os solos estudados. No estudo de dissipação, a taxa de transformação do herbicida em condições aeróbicas além da natureza e taxa de formação e declínio de produtos de transformação do herbicida foram acessados. Um modelo exponencial de primeira ordem foi utilizado para ajustar a dissipação do herbicida nos solos. A meia-vida do herbicida foi de 22, 15, 110 e 39 nos solos GMa, LVdf, RQ e PV, respectivamente. Uma avaliação de risco ambiental inicial do herbicida foi acessada pelo uso do método dos quocientes (RQ risk quotient), sendo risco = exposição/efeito. A exposição é representada pela Concentração Ambiental Esperada (CAE) e foi avaliada nos compartimentos ambientais solo, águas superficiais e águas subterrâneas. Os cálculos de CAE foram obtidos por avaliação de cenários simples do tipo pior caso nos diferentes compartimentos e pelo emprego dos modelos matemáticos GENEEC e SCIGROW para águas superficiais e subterrâneas, respectivamente. Na estimativa do efeito, usou-se os valores limite (endponts, exemplos: EC50, NOEC) disponíveis para diferentes organismos representantes dos diferentes compartimentos ambientais estudados. O resultado do quociente exposição/efeito foi comparado com os níveis de preocupação (LOC level of concern) empregados pelo EPA para avaliação do potencial risco do uso deste herbicida para os diferentes organismos representativos dos diferentes compartimentos ambientais estudados. Assumindo o pior cenário (menor valor de Kd e maior valor de DT50), as estimativas das CAEs foram baixas e iguais a 0,024 mg kg-1 no solo, a 0,0008 mg L-1 na água superficial e a 0,04 \'mü\' L-1 na água subterrânea. Os valores de RQ obtidos (< 1 e inferiores aos respectivos LOCs) indicaram baixo potencial de risco do uso deste herbicida para os diferentes organismos, representativos dos diversos compartimentos ambientais estudados / A new active ingredient of the triazolopyrimidine sulfonamide herbicide class from the ALS group is under development. This is an ionizable herbicide with weakly acidic behavior (pKa = 4.67). Its solubility in water depends on pH, it is a hydrolytically stable molecule, being highly susceptible to photodegradation in aqueous medium. The photodegradation in soil is not significant. This study evaluated the potential of sorption, leaching and dissipation of this herbicide in four Brazilian soils: Gleissolo Melânico Alumínico típico (GMa), Latossolo Vermelho Distroférrico típico (LVdf), Neossolo Quartzarênico órtico típico (RQ) e Argissolo Vermelho eutroférrico chernossólico (PV). In the study of sorption isotherms were fitted using the Freundlich model and the values of sorption coefficients (Kd) ranged from 0.5 to 22.4 g mL-1 indicating a potential low to moderate sorption. In the study of mobility, no radioactivity was observed in the leachate collected until 48 hours in soils GMa, LVdf and PV, in the soil RQ was detected about 2% of applied radioactivity. The results of comparative mobility suggest that the herbicide is classified as moderately mobile by the criterion of Relative Mobility Factor (FMR) in all soils. In the study of dissipation, the rate of transformation of the herbicide under aerobic conditions and rate of formation and decline of transformation products of herbicide were accessed. A first order exponential model was used to adjust the dissipation of the herbicide in soils. The half-life of the herbicide was 22, 15, 110 and 39 days in soils GMa, LVdf, RQ and PV, respectively. An initial environmental risk assessment of the herbicide was accessed by using the method of quotient (RQ - risk quotient), RQ = exposure / effect. The exposure is represented by the Expected Environmental Concentration (EEC) and was evaluated in the environmental compartments soil, surface water and groundwater. EEC calculations were obtained by assessing simple scenarios such as \"worst case\" in the different compartments and the use of mathematical models GENEEC and SCIGROW to surface and groundwater assessments, respectively. In estimating the effect, endponts (examples: EC50, NOEC) available for different organisms representative from the different environmental compartments studied were used. The result of the quotient exposure / effect was compared to the \"levels of concern (LOC - level of concern) employed by the EPA to assess the potential risk from use of this herbicide for different organisms representing different environmental compartments studied. Assuming the worst case scenario (lower Kd value and higher value of DT50), the estimates of EECs were low and equal to 0.024 mg kg-1 soil, 0.0008 mg L-1 in surface water and 0.04 \'mü\' L-1 in the groundwater. The RQ values obtained (< 1 and below the respective LOCs) indicated low potential risk from use of this herbicide for different organisms, representative from different environmental compartments studied
55

IDENTIFYING PERCEIVED RISKS TO ENVIRONMENTAL POLLUTANTS AND NEEDS FOR RISK COMMUNICATION IN A RURAL APPALACHIAN COMMUNITY

Travis, Elizabeth H. 01 January 2018 (has links)
The goal of this study is to determine issues rural Appalachian residents consider most important, their perceived environmental health risk, and how community engagement can potentially improve those issues. The University of Kentucky Superfund Research Center held the Appalachian Community Health and Well-being Forum at the Letcher County Cooperative Extension Office in Eastern Kentucky. A four-member panel consisted of two local health officials, a nutrition expert, and a federal scientist; answered questions from community members. The expert panel and audience members shared concerns, success stories, and highlighted efforts to promote health in the region. Community members completed a questionnaire collecting information on perceived environmental health risk, fruit and vegetable intake, and basic demographic information. The concerns raised by community members were chronic disease, poverty, pollution, mental health, and wellness. Proposed solutions were compliance, nutrition, physical activity, education, empathy, funding, community engagement, awareness, holistic health, prevention, and insurance/policy change. The programs in place to combat these issues are FARMACY, Community Health Workers, transportation services, mobile dental vans, Kentucky River Watershed Watch, research, policy changes, and the CLIK program. The questionnaire showed that residents are aware of the types of pollution in their community and believe that illness is caused by pollution in their environment. Community residents feel that pollution is not something they should have to live with, they act to protect themselves from pollution, and likely to engage in community efforts to stop pollution in their community.
56

Does normal developmental expression of psychosis combine with environmental risk to cause persistence of psychosis? A psychosis proneness-persistence model

Cougnard, Audrey, Marcelis, Machteld, Myin-Germeys, Inez, De Graaf, Ron, Vollebergh, Wilma A. M., Krabbendam, Lydia, Lieb, Roselind, Wittchen, Hans-Ulrich, Henquet, Cécile, Spauwen, Janneke, Van Os, Jim 29 January 2013 (has links) (PDF)
Background. Research suggests that low-grade psychotic experiences in the general population are a common but transitory developmental phenomenon. Using two independent general population samples, the hypothesis was examined that common, non-clinical developmental expression of psychosis may become abnormally persistent when synergistically combined with developmental exposures that may impact on behavioural and neurotransmitter sensitization such as cannabis, trauma and urbanicity. Method. The amount of synergism was estimated from the additive statistical interaction between baseline cannabis use, childhood trauma and urbanicity on the one hand, and baseline psychotic experiences on the other, in predicting 3-year follow-up psychotic experiences, using data from two large, longitudinal, random population samples from the Netherlands [The Netherlands Mental Health Survey and Incidence Study (NEMESIS)] and Germany [The Early Developmental Stages of Psychopathology (EDSP) study]. Results. The 3-year persistence rates of psychotic experiences were low at 26% in NEMESIS and 31% in EDSP. However, persistence rates were progressively higher with greater baseline number of environmental exposures in predicting follow-up psychotic experiences (χ2=6·9, df=1, p=0·009 in NEMESIS and χ2=4·2, df=1, p=0·04 in EDSP). Between 21% and 83% (NEMESIS) and 29% and 51% (EDSP) of the subjects exposed to both environmental exposures and psychotic experiences at baseline had persistence of psychotic experiences at follow-up because of the synergistic action of the two factors. Conclusion. The findings suggest that environmental risks for psychosis act additively, and that the level of environmental risk combines synergistically with non-clinical developmental expression of psychosis to cause abnormal persistence and, eventually, need for care.
57

Soft computing approaches to uncertainty propagation in environmental risk mangement

Kumar, Vikas 19 June 2008 (has links)
Real-world problems, especially those that involve natural systems, are complex and composed of many nondeterministic components having non-linear coupling. It turns out that in dealing with such systems, one has to face a high degree of uncertainty and tolerate imprecision. Classical system models based on numerical analysis, crisp logic or binary logic have characteristics of precision and categoricity and classified as hard computing approach. In contrast soft computing approaches like probabilistic reasoning, fuzzy logic, artificial neural nets etc have characteristics of approximation and dispositionality. Although in hard computing, imprecision and uncertainty are undesirable properties, in soft computing the tolerance for imprecision and uncertainty is exploited to achieve tractability, lower cost of computation, effective communication and high Machine Intelligence Quotient (MIQ). Proposed thesis has tried to explore use of different soft computing approaches to handle uncertainty in environmental risk management. The work has been divided into three parts consisting five papers. In the first part of this thesis different uncertainty propagation methods have been investigated. The first methodology is generalized fuzzy &#945;-cut based on the concept of transformation method. A case study of uncertainty analysis of pollutant transport in the subsurface has been used to show the utility of this approach. This approach shows superiority over conventional methods of uncertainty modelling. A Second method is proposed to manage uncertainty and variability together in risk models. The new hybrid approach combining probabilistic and fuzzy set theory is called Fuzzy Latin Hypercube Sampling (FLHS). An important property of this method is its ability to separate randomness and imprecision to increase the quality of information. A fuzzified statistical summary of the model results gives indices of sensitivity and uncertainty that relate the effects of variability and uncertainty of input variables to model predictions. The feasibility of the method is validated to analyze total variance in the calculation of incremental lifetime risks due to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) for the residents living in the surroundings of a municipal solid waste incinerator (MSWI) in Basque Country, Spain. The second part of this thesis deals with the use of artificial intelligence technique for generating environmental indices. The first paper focused on the development of a Hazzard Index (HI) using persistence, bioaccumulation and toxicity properties of a large number of organic and inorganic pollutants. For deriving this index, Self-Organizing Maps (SOM) has been used which provided a hazard ranking for each compound. Subsequently, an Integral Risk Index was developed taking into account the HI and the concentrations of all pollutants in soil samples collected in the target area. Finally, a risk map was elaborated by representing the spatial distribution of the Integral Risk Index with a Geographic Information System (GIS). The second paper is an improvement of the first work. New approach called Neuro-Probabilistic HI was developed by combining SOM and Monte-Carlo analysis. It considers uncertainty associated with contaminants characteristic values. This new index seems to be an adequate tool to be taken into account in risk assessment processes. In both study, the methods have been validated through its implementation in the industrial chemical / petrochemical area of Tarragona. The third part of this thesis deals with decision-making framework for environmental risk management. In this study, an integrated fuzzy relation analysis (IFRA) model is proposed for risk assessment involving multiple criteria. The fuzzy risk-analysis model is proposed to comprehensively evaluate all risks associated with contaminated systems resulting from more than one toxic chemical. The model is an integrated view on uncertainty techniques based on multi-valued mappings, fuzzy relations and fuzzy analytical hierarchical process. Integration of system simulation and risk analysis using fuzzy approach allowed to incorporate system modelling uncertainty and subjective risk criteria. In this study, it has been shown that a broad integration of fuzzy system simulation and fuzzy risk analysis is possible. In conclusion, this study has broadly demonstrated the usefulness of soft computing approaches in environmental risk analysis. The proposed methods could significantly advance practice of risk analysis by effectively addressing critical issues of uncertainty propagation problem. / Los problemas del mundo real, especialmente aquellos que implican sistemas naturales, son complejos y se componen de muchos componentes indeterminados, que muestran en muchos casos una relación no lineal. Los modelos convencionales basados en técnicas analíticas que se utilizan actualmente para conocer y predecir el comportamiento de dichos sistemas pueden ser muy complicados e inflexibles cuando se quiere hacer frente a la imprecisión y la complejidad del sistema en un mundo real. El tratamiento de dichos sistemas, supone el enfrentarse a un elevado nivel de incertidumbre así como considerar la imprecisión. Los modelos clásicos basados en análisis numéricos, lógica de valores exactos o binarios, se caracterizan por su precisión y categorización y son clasificados como una aproximación al hard computing. Por el contrario, el soft computing tal como la lógica de razonamiento probabilístico, las redes neuronales artificiales, etc., tienen la característica de aproximación y disponibilidad. Aunque en la hard computing, la imprecisión y la incertidumbre son propiedades no deseadas, en el soft computing la tolerancia en la imprecisión y la incerteza se aprovechan para alcanzar tratabilidad, bajos costes de computación, una comunicación efectiva y un elevado Machine Intelligence Quotient (MIQ). La tesis propuesta intenta explorar el uso de las diferentes aproximaciones en la informática blanda para manipular la incertidumbre en la gestión del riesgo medioambiental. El trabajo se ha dividido en tres secciones que forman parte de cinco artículos. En la primera parte de esta tesis, se han investigado diferentes métodos de propagación de la incertidumbre. El primer método es el generalizado fuzzy &#945;-cut, el cual está basada en el método de transformación. Para demostrar la utilidad de esta aproximación, se ha utilizado un caso de estudio de análisis de incertidumbre en el transporte de la contaminación en suelo. Esta aproximación muestra una superioridad frente a los métodos convencionales de modelación de la incertidumbre. La segunda metodología propuesta trabaja conjuntamente la variabilidad y la incertidumbre en los modelos de evaluación de riesgo. Para ello, se ha elaborado una nueva aproximación híbrida denominada Fuzzy Latin Hypercube Sampling (FLHS), que combina los conjuntos de la teoría de probabilidad con la teoría de los conjuntos difusos. Una propiedad importante de esta teoría es su capacidad para separarse los aleatoriedad y imprecisión, lo que supone la obtención de una mayor calidad de la información. El resumen estadístico fuzzificado de los resultados del modelo generan índices de sensitividad e incertidumbre que relacionan los efectos de la variabilidad e incertidumbre de los parámetros de modelo con las predicciones de los modelos. La viabilidad del método se llevó a cabo mediante la aplicación de un caso a estudio donde se analizó la varianza total en la cálculo del incremento del riesgo sobre el tiempo de vida de los habitantes que habitan en los alrededores de una incineradora de residuos sólidos urbanos en Tarragona, España, debido a las emisiones de dioxinas y furanos (PCDD/Fs). La segunda parte de la tesis consistió en la utilización de las técnicas de la inteligencia artificial para la generación de índices medioambientales. En el primer artículo se desarrolló un Índice de Peligrosidad a partir de los valores de persistencia, bioacumulación y toxicidad de un elevado número de contaminantes orgánicos e inorgánicos. Para su elaboración, se utilizaron los Mapas de Auto-Organizativos (SOM), que proporcionaron un ranking de peligrosidad para cada compuesto. A continuación, se elaboró un Índice de Riesgo Integral teniendo en cuenta el Índice de peligrosidad y las concentraciones de cada uno de los contaminantes en las muestras de suelo recogidas en la zona de estudio. Finalmente, se elaboró un mapa de la distribución espacial del Índice de Riesgo Integral mediante la representación en un Sistema de Información Geográfico (SIG). El segundo artículo es un mejoramiento del primer trabajo. En este estudio, se creó un método híbrido de los Mapas Auto-organizativos con los métodos probabilísticos, obteniéndose de esta forma un Índice de Riesgo Integrado. Mediante la combinación de SOM y el análisis de Monte-Carlo se desarrolló una nueva aproximación llamada Índice de Peligrosidad Neuro-Probabilística. Este nuevo índice es una herramienta adecuada para ser utilizada en los procesos de análisis. En ambos artículos, la viabilidad de los métodos han sido validados a través de su aplicación en el área de la industria química y petroquímica de Tarragona (Cataluña, España). El tercer apartado de esta tesis está enfocado en la elaboración de una estructura metodológica de un sistema de ayuda en la toma de decisiones para la gestión del riesgo medioambiental. En este estudio, se presenta un modelo integrado de análisis de fuzzy (IFRA) para la evaluación del riesgo cuyo resultado depende de múltiples criterios. El modelo es una visión integrada de las técnicas de incertidumbre basadas en diseños de valoraciones múltiples, relaciones fuzzy y procesos analíticos jerárquicos inciertos. La integración de la simulación del sistema y el análisis del riesgo utilizando aproximaciones inciertas permitieron incorporar la incertidumbre procedente del modelo junto con la incertidumbre procedente de la subjetividad de los criterios. En este estudio, se ha demostrado que es posible crear una amplia integración entre la simulación de un sistema incierto y de un análisis de riesgo incierto. En conclusión, este trabajo demuestra ampliamente la utilidad de aproximación Soft Computing en el análisis de riesgos ambientales. Los métodos propuestos podría avanzar significativamente la práctica de análisis de riesgos de abordar eficazmente el problema de propagación de incertidumbre.
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Beräkning av massbalanser för metaller i vatten samt miljöriskbedömning av Nerån vid Österbyverken i Östhammars kommun

Ladekrans, Thereze January 2011 (has links)
Österbyverken is an industrial estate in Östhammars municipality in Uppland, Sweden. Many different activities have taken place on the estate the last 600 years. During the last 15 years both health and environmental studies have been made by different companies. At the most recent study a great increase of metals in Nerån, a river that runs partly through and partly next to the estate, was identified with mass balances. The purpose of this thesis is to accomplish a deepened study about the reasons for the increase of metals in Nerån. The aim is to identify knowledge gaps in the mass balances and try to complete these. From the outcome an environmental risk assessment will be attempted for Nerån and its outlet in the lake Filmsjön. The method went through steps and started with data analyses after which calculations for new mass balances were made. Beginning by acknowledge the increase of metals from the groundwater, both through measured results and through calculated confidence intervals. In addition, among other methods, calculations of theoretical leakage data from Kd-values were made. Surface water concentrations were also compared with levels of metals in sediments to see whether any connection existed between them. Additional mass balances were calculated to take suspended solids in the surface water under consideration. From the results an environmental risk assessment was made using guidelines from Netherland and Canada and the state division from the Swedish Environmental Protection Agency. The results of the study show that the differences of metal content between surface water and groundwater and between surface water and sediments might be smaller than first revealed, but there is still a great increase caused by another, unknown source. The environmental risk assessment shows that there are hazards for both Nerån and Filmsjön because of the leakage of metals from Österbyverken. For the surface water in Nerån it is mainly cobalt, copper and zinc that contributes with risks, for the sediment in Nerån it is mainly barium, cobalt, copper, chromium and nickel and for the sediments in Filmsjön it is mainly lead, cobalt, copper, chromium, nickel and zinc. Reasons for the differences between metal contents and medias might be from surface water outlet from the Österbyverken or because of differences in methods of taking specimens in surface and groundwater. Conclusions that have been drawn of the study is that further studies of the knowledge gaps needs to be done, particularly regarding the metals cobalt, copper, chromium, nickel and zinc. Further, the biodiversity in Nerån and Filmsjön is at risk, partly because several metals in the sediments reaches such high concentrations, partly because high concentrations of several metals in one area may increase risks.
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Environmental risks, subjectivity, and political choices : the Korean case /

You, Seungkwon, January 2002 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 231-239). Also available on the Internet.
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Environmental risks, subjectivity, and political choices the Korean case /

You, Seungkwon, January 2002 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 231-239). Also available on the Internet.

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