The impact of natural and anthropogenic disturbances on catchment hydrological and biogeochemical dynamics are difficult or impossible to capture through experimentation or observation alone. Process-based simulation models can address this need by providing a framework for synthesizing data describing catchment responses to climate, harvest, fire, and other disturbances. However, existing models are either too simple to capture important process-level hydrological and biogeochemical controls on ecosystem responses to disturbance, or are too computationally expensive to simulate the local dynamics over large watershed areas, or require a high level of expertise to implement. To this end, a spatially distributed, physically based, eco-hydrological model (VELMA: Visualizing Ecosystems for Land Management Assessments) that is both computationally efficient and relatively easy to implement is developed. VELMA is a state-of-the-art model with real-time visualization tools that shows temporal and spatial patterns of state and flux variables, and is used to address the effects of changes in climate, land-use, and other interacting stressors on multiple ecosystem services such as timber production, carbon sequestration, regulation of water quality and quantity and reduction of greenhouse gases at scales relevant to formulating management decisions. In this study, VELMA was applied to the H.J. Andrews Experimental forest, an intensively studied watershed with observed daily temperature, precipitation, streamflow, and nutrient losses data. VELMA was first used to explore the factors that controls catchment response to forest harvest. Specifically, elucidate how forest harvest factors such as harvest location and amount control watershed hydrological and biogeochemical fluxes. Thereafter, VELMA was used to reconstruct and analyze the impact of two significant disturbance events − a stand replacing fire and a 100% clearcut − on vegetation and soil carbon and nitrogen dynamics. Finally, VELMA was used to explore the potential impact of climate change on catchment hydrological regime, site productivity and carbon and nitrogen dynamics at high spatial resolution relevant to formulating management decision. The main insights from this study include: (1) streamflow, nutrient losses to the stream, and gaseous carbon and nitrogen losses to the atmosphere are strongly sensitive to the location of harvest as a result of the spatial variation in soil water content, plant nitrogen uptake, soil organic carbon decomposition, nitrification, and denitrification within the watershed, (2) forested riparian buffers reduce water and nutrient losses to the stream through plant transpiration, plant nitrogen uptake, soil storage, and soil microbial decomposition, (3) following fire and harvest, losses of N from the terrestrial system to the stream are tightly constrained by the hydrological cycle and driven mainly by wet-season rain events large enough to generate hydrologic connectivity and flushing of nutrients along hillslopes, (4) climate change strongly impacts the hydrological regime in the Pacific Northwest as a result of less snowpack, earlier snowmelt, higher winter streamflow, lower summer streamflow, and soil moisture deficit, and (5) climate change increases plant and soil biomass accumulation as a result of longer growing season and higher soil organic decomposition, reduce water quality by increasing the amount of nutrients that reach the stream, and transforms the ecosystem into a net source of carbon to the atmosphere.

Die zentralen Fragestellungen der Arbeit sind, wie die Insolvenzwahrscheinlichkeiten von Unternehmen prognostiziert und wie sie durch zielgerichtetes Handeln beeinflusst werden können. Hierzu gibt der Autor zunächst einen ausführlichen Überblick über die derzeit in Wissenschaft und Praxis verwendeten Ansätze zur Prognose von Unternehmensinsolvenzen, Schätzgütemaßen von Insolvenzprognosen sowie Datenquellen, die für die Prognose von Unternehmensinsolvenzen zur Verfügung stehen. Anschließend entwickelt er ein kausales Unternehmensmodell, das er mit stochastischen Simulationsverfahren analysiert. Das Modell wird validiert und mit Benchmarkverfahren verglichen. Abschließend zeigt der Autor, wie das Modell zur Ableitung von Handlungsempfehlungen zur Beeinflussung der individuellen Insolvenzwahrscheinlichkeit von Unternehmen herangezogen werden kann.

<p>Traditionally, research on cross‐country skiing biomechanics is based mainly on experimental testing alone. Trying a different approach, this thesis explores the possibilities of using computational musculoskeletal biomechanics for cross‐country skiing. As far as the author knows, this has not been done before.</p><p>Cross‐country skiing is both fast and powerful, and the whole body is used to generate movement. Consequently, the computational method used needs to be able to handle a full‐body model with lots of muscles. This thesis presents several simulation models created in the AnyBody Modeling System, which is based on inverse dynamics and static optimization. This method allows for measurementdriven full‐body models with hundreds of muscles and rigid body segments of all major body parts.</p><p>A major result shown in the thesis is that with a good simulation model it is possible to predict muscle activation. Even though there is no claim of full validity of the simulation models, this result opens up a wide range of possibilities for computational musculoskeletal biomechanics in cross‐country skiing. Two example of new possibilities are shown in the thesis, finding antagonistic muscle pairs and muscle load distribution differences in different skiing styles. Being able to perform optimization studies and asking and answering “what if”‐questions really gives computational methods an edge compared to traditional testing.</p><p>To conclude, a combination of computational and experimental methods seems to be the next logical step to increase the understanding of the biomechanics of crosscountry skiing.</p> / <p>Traditionellt har biomekaniska forskningsstudier av längdskidåkning baserats helt och hållet på experimentella metoder. För att prova ett annat angreppssätt undersöks i denna avhandling vilka möjligheter som beräkningsbaserad biomekanik kan ge för längdskidåkning. Så vida författaren vet, har detta inte gjorts tidigare.</p><p>Längdskidåkning innehåller snabba och kraftfulla helkroppsrörelser och därför behövs en beräkningsmetod som kan hantera helkroppsmodeller med många muskler. Avhandlingen presenterar flera simuleringsmodeller skapade i AnyBody Modeling System, som baseras på inversdynamik och statisk optimering. Denna metod tillåter helkroppsmodeller med hundratals muskler och stelkroppssegment av de flesta kroppsdelarna.</p><p>Ett resultat som avhandlingen visar är att med en bra simuleringsmodell är det möjligt att förutsäga muskelaktiviteten för en viss rörelse och belastning på kroppen. Även om ingen validering av simuleringsmodellen ges, så visar ändå resultatet att beräkningsbaserad biomekanik ger många nya möjligheter till forskningsstudier av längdskidåkning. Två exempel visas, hur muskelantagonister kan hittas samt hur lastfördelningen mellan musklerna förändras då skidåkaren förändrar stilen. Att kunna genomföra optimeringsstudier samt fråga och svara på ”vad händer om”‐ frågor ger beräkningsbaserad biomekanik en fördel i jämförelse med traditionell testning.</p><p>Slutsatsen är att en kombination av beräkningsbaserade och experimentella metoder borde vara nästa steg för att addera insikt om längdskidåkningens biomekanik.</p> / Report code: LIU‐TEK‐LIC‐2008:4. On the day of the defence date the status of article V was: Submitted.

One of the challenges for Airbus preparing a new freighter development process was the design of a solid freighter barrier, which separates the courier area from the cargo compartment. The major task of such a barrier is to protect the passengers against all risks caused due to cargo impact by a justifiable design. These risks may result from all kind of survivable incident and accident scenarios. Real aircraft crashes were analyzed to get away from a static book-case and come to a more realistic dynamic crash scenario. A reduced-order simulation model was built up to investigate and simulate the dynamic effects during crash. The simulation model considers the highly nonlinear stiffness and damping characteristics of all critical cargo types and also includes their energy absorption potentials. A series of full scale container crash tests have been performed at accredited car crash facilities. The test campaigns were complemented by numerous component tests to study also general crash principles. The critical simulation parameters were identified and implemented into the simulation model. The subsequent validation process showed a close agreement between simulation and test. The simulation environment has turned out to be a reliable basis to simulate all critical barrier loads with respect to the specific aircraft loading distributions. The essence of this investigation is an adequate understanding of the real crash effects. The proposed dynamic crash approach is more realistic than the static condition and results in an optimized safety barrier wall concept. This dynamic approach provides equivalent safety compared to the existing devices and is accepted by FAA and EASA.

Šiuo metu egzistuoja įvairiausių sudėtingų sistemų imitacinių modelių kūrimo technologijų ir priemonių. Šiame darbe aiškinama, kaip imitacinis modelis gali būti integruojamas į verslo valdymo sistemą. Taip pat įvertinama, kad verlo valdymo sistemos gali būti paskirstytos atskiruose kompanijose ar kompiutersiuose. Šiame darbe bus išanalizuota koncepcija, kaip apjungti atskirus imitacinius modelius. Išanalizuota modelių integravimo į informacinę sistemą technologija. Pateikiami gamybos ir paskirstymo imitacinių modelių matematiniai aprašai, naudojant DEVS(Discrete Event Simulation) ir PLA(Piece-Linear Aggregates) specifikacijų metodus. / At present, a large number of modeling and simulation techniques and tools have been developed to deal with complex business systems. In this paper, we concentrate on scenario illustrating, how simulation models can be integrated in to business management system. Different infrastructure forms are possible, because services may be implemented on single machine or distributed throughout several companies’ networks. In this paper a concept will be analyzed - how to combine different simulation models. The technology for involvement of simulation models in to information systems will be created. Also the problem of simulation model transformation in to program code will be solved. For model formalization we can use a method of Piece-Linear Aggregates (PLA) that belongs to the class of time automata model. PLA method is close to Discrete Event Simulation (DEVS) formalism, which is used to create wide purpose simulation models.

Este trabalho está voltado à avaliação dos problemas do transporte intermodal sob efeito de restrições sazonais que, usualmente, não são consideradas na fase de planejamento e dimensionamento da frota. E, considerando a sobreposição de dois fatores sazonais restritivos ao longo da cadeia de transportes - a variação na produção de grãos ao longo do ano e a sazonalidade das cotas de nível d\'água nas hidrovias -, um modelo de simulação de eventos discretos mostra as impedâncias sofridas no sistema pela junção de fatores restritivos bem fortes. É possível avaliar o impacto dessas restrições não só no nível de utilização dos silos intermediários e silagem do porto, mas também no número de veículos necessários para fazer o transporte de commodities na região Centro-Oeste do Brasil. Em um sistema de transporte composto pelos modais rodoviário, hidroviário e marítimo, no qual o modelo de simulação abrange desde a produção nas fazendas, passando pelo transporte de caminhão até os armazéns intermediários, posteriormente com o transporte fluvial com destino ao porto para exportação. O presente estudo traz uma série de comparações entre cenários para avaliação dos gargalos existentes neste sistema de transporte intermodal, especialmente avaliando cenários com e sem as restrições sazonais, assim como análises de sensibilidade de performance de equipamentos de carregamento e descarregamento, nos quais a frota e os estoques necessários são substancialmente diferentes se a sazonalidade não for considerada. / This work focuses on the evaluation of the intermodal transport problems under the influence of seasonal constraints that are not usually considered on the phase of planning and sizing the fleet. Considering the superposition of two different seasonal factors along the transportation chain - first one the variation on grain production and the second one the level of water in the waterways throughout the year -, a discrete event simulation model was built to show the real effects of those constraints in the grain supply chain. So, it is possible to evaluate the impact of those constraints not only on the usage level of storages in this system, but also the number of vehicles required to transport this commodities from the Midwest of Brazil to the port. In a complex multimodal transportation system, the simulation model in this work includes roadways, waterways and seaways to transport all the cargo from farms to the final costumer. This study is composed by a number of scenarios to evaluate the bottlenecks in this intermodal transportation system, specially analyzing scenarios with and without seasonal constraints, as well as analysis of sensitivity of performance of equipment of loading and unloading, in which the fleet and the required stocks are substantially different if seasonality is not considered. In other words, it is possible to evaluate the risks involved when managers are making decisions if they do not take in consideration any of those seasonal constraints.

Orientador: Jose Teixeira Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-08-09T16:44:54Z (GMT). No. of bitstreams: 1 Pereira_VaniaRosa_M.pdf: 9033260 bytes, checksum: fb1eddf01d9611ec998222350bd7b966 (MD5) Previous issue date: 2007 / Resumo: Os processos de erosão, transporte e deposição em rochas e solos fazem parte do ciclo erosivo, cuja intensidade de produção de sedimentos dependerá das interações entre os elementos naturais da paisagem. Entretanto, as ações antrópicas, como as atividades agrícolas e os desmatamentos, alteram os processos erosivos, provocando um desequilíbrio nas inter-relações naturais dos componentes da paisagem, desencadeando, entre outros fatores, o aceleramento da produção de sedimentos. O processo da produção de sedimentos está relacionado também às fontes de poluição difusa, pois os processos erosivos não incluem apenas o transporte de partículas de sedimentos, mas também transportam nutrientes e poluentes. Associada às questões relacionadas à qualidade e disponibilidade de água, a degradação dos sistemas hídricos pode diminuir o tempo de vida útil de reservatórios de abastecimento de água para consumo ou para produção de energia elétrica, acarretando prejuízos para a sociedade. Visando contribuir para o planejamento ambiental com ênfase na manutenção da qualidade e da disponibilidade de água, bem como da vida útil dos reservatórios, definiu-se, como objetivo deste trabalho, identificar as áreas com potencial para a produção de sedimentos nas bacias do rio Atibainha e do rio Cachoeira a montante das barragens do sistema Cantareira, por se tratar de uma área de importância regional que abastece a região metropolitana de São Paulo e Campinas. A metodologia envolve a análise e cruzamento de três planos de informação - meio físico, procedimento e uso da terra e adequação do uso das terras em relação à aptidão agrícola - espacializados em ambiente de Sistemas de Informação Geográfica (SIG). Como resultado tem-se a espacialização das áreas com potencial de alto, médio e baixo risco para a produção de sedimentos. A identificação das áreas de risco para as bacias do Atibainha e Cachoeira demonstrou não haver grandes diferenças entre uma bacia e outra: a bacia do rio Atibainha apresentou 44 % de áreas de baixo risco, 26 % de médio e 30 % de alto risco enquanto a bacia do rio Cachoeira apresentou 32 % de baixo, 24 % de médio e 44 % de alto risco. Como as bacias se comportam de forma muito similar, não concorrem entre si em termos de prioridade de medidas conservacionistas. As áreas de risco com potencial para a produção de sedimentos identificadas neste modelo não foram determinadas por nenhuma variável utilizada; ou seja, nas áreas de alto risco, predominaram todas as classes de solo, em diversas declividades e intensidades de chuva. Embora as áreas de alto risco distribuam-se preferencialmente nas áreas de fundo de vale (com alto potencial de produção de sedimentos), as relações entre as variáveis é que determinaram o grau de risco de cada área. Tendo em vista os objetivos deste trabalho, pode-se afirmar que esse modelo de espacialização pode ser utilizado para subsidiar estudos de planejamento conservacionista, pois fornece indicações de áreas prioritárias de planejamento conservacionista em função da realidade sócio-econômica-ambiental / Abstract: The erosion, transport and soil and rocks deposition processes make part of erosion cicle, ofwhich the sediment yield intensity depends on the interaction between landscape natural elements. However, antrophic actions such as agricultural activities and deforestations, modify the erosive processes, causing a disequilibrium in the natural Inter-relations of the landscape components, setting off the sediment yield acceleration among others factors.The sediment yield process is also related to non-point sources pollution, since the erosive processes do not include only the transport of sediment particle, but also the transport of nutrients and pollutants. The hydrics systems degradation can diminish useful reservoirs life time of consumption water supply or electric energy production, causing damages for the society and, therefore, is associated to the questions related to quality and water availability. It was defined, as objective of this work, to identify the potential sediment yield areas in the Atibainha river and Cachoeira river watersheds upstream Cantareira system catchments, aiming to contribute for the environment planning in an area of regional importance that supplies São Paulo and Campinas metropolitan region with emphasis on the quality and water availability maintenance, as well as the useful reservoirs life time. The methodology involved the analysis and three plans information crossing ¿ physical environment, land use and procedure and land use adequacy, by means of agricultural suitability - identificated in Geographic Information System (GIS) environment. As a result it was obtained the potential of high, average and low risk for sediment yield areas identification. The identification of the Atibainha and Cachoeira watersheds risk areas demonstrated not to have great differences between them: the Atibainha river watershed presented 44 % of low risk areas, 26 % of medium and 30 % of high risk while the Cachoeira river watershed presented 32 % of low, 24 % of medium and 44 % of high risk. As the watershed had very similar hold, they do not concur between itself in environment planning priority terms. The potential sediment yield risk areas identified in this model had not been determined by only one used variable, this means that all soil classes had predominated in diverse declivities and intensities of rainfall in the high risk areas. Although high risk areas are distributed preferentially in the areas of valley deep, the degree of risk of each area was determined by the relations between the variables. Therefore, it can be suggested that this identification model could be used to support studies of environment planning, since it supplies indications of conservation planning priority areas as a function of the social-economic-environment reality / Mestrado / Análise Ambiental e Dinâmica Territorial / Mestre em Geografia

No gerenciamento de recursos hídricos, a bacia hidrográfica é considerada a unidade natural de gestão. Suas características físicas definem um espaço onde a água converge para uma saída comum. O desenvolvimento integrado de uma bacia, bem como os possíveis conflitos ocasionados por demandas concorrentes do mesmo recurso, devem ser administrados respeitando esse conceito de unidade. No caso específico da bacia hidrográfica do Rio Jaguari, existe uma crescente preocupação relacionada aos usos múltiplos da água superficial. O rio Jaguari, importante afluente do Paraíba do Sul no estado de São Paulo, tem suas águas represadas para geração de energia elétrica e regularização de vazões. Nos últimos anos, tem-se constatado um crescente rebaixamento dos níveis operacionais da represa do Jaguari. Segundo estudos da sociedade civil organizada local, a tendência é de esgotamento do reservatório em poucos anos. Este trabalho aborda a questão do rebaixamento dos níveis de Jaguari através da aplicação do software DHI Mike Basin 2000. Trata-se de um simulador genérico para sistemas de recursos hídricos, de ampla aplicação. A bacia do Jaguari é representada em um modelo matemático e são simulados quatro cenários distintos de usos de água na bacia. Verifica-se que o problema é real e requer uma intervenção multi-institucional para ser solucionado. / In the management of water resources, basin is naturally considered the administration unit. Its physical properties define a land space where water flows on the way to a common outlet. The integrated development of a basin, as well as potential conflicts resulted by divergent users should be managed under this unit concept. On Jaguari river basin, in state of São Paulo, Brazil, there is an emergent concern related to the multiplicity of water uses. Jaguari river, an important branch of Paraíba do Sul river in state of São Paulo is dammed for the generation of electricity and stream flow regulation. In last years, it has been observed an increasing reduction in Jaguari reservoir operational levels. According to local organizations\' studies, the reservoir trends to collapse in few years. The present dissertation holds a discussion about the reduction of water level trend in Jaguari reservoir, through the application of DHI MIKE BASIN 2000 software. It is a generic, very useful simulator for water resources systems. The Jaguari basin is represented by a mathematic model, simulated for four different water use scenarios. It is shown that the problem is real, and requires a multi-institutional intervention to be solved.

Dissertation work comes with a summary of logistics evolution in the sphere of Supply Chain Management and focuses readers attention on the processes inside of supply chain. However dissertaion work is not just a huge methodological part, it also comes with an optimization part. Reader meets imaginary company trying to optimize a part of its distribution process by using modification of distribution technology "Hub and Spoke". Optimization computational procedure also consist of Traveller Salesman Problem (TSP). Fictional data for three days of testing where prepared by using MS Excel function of random numbers. For longer testing period dissertation work uses simulation technology represented by SIMPROCESS software.

Aim of this thesis is to analyze the current situation, to identify bottlenecks and to propose improvements to the department of acquisitions in the selected financial company, which is an important part of the Czech market and which desire not to be named. In the first part of my thesis is provided to the reader a theoretical basis necessary to understand the following text. Then I create simulation models for individual teams, which take part in the mentioned department. These models are based only on average and total values. That is why in the next section, there is described the work to bring them closer to reality with shifts of administrators and the variable number of entities, which are processed throughout the day. Based on the analysis of calculated values, I propose two methods of redistribution of actions to reduce the number of employees and to increase their efficiency.