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Desenvolvimento de um macromodelo biomecânico tridimensional da coluna vertebral durante tarefas de levantamentoLa Torre, Marcelo January 2009 (has links)
As atividades desenvolvidas pelo ser humano traduzem-se em grandes esforços internos, sobre as mais variadas estruturas corporais. O conhecimento da magnitude destes esforços pode auxiliar profissionais da área da saúde em atividades como prescrição de exercícios, reabilitação e prevenção de lesões. A magnitude dos esforços internos pode ser obtida por meio de um método direto ou indireto. O método direto esbarra em questões éticas e limitações tecnológicas, enquanto que o método analítico indireto por meio do conhecimento de parâmetros biomecânicos externos pode inferir sobre os esforços internos. Assim o objetivo deste estudo foi implementar um Macromodelo biomecânico tridimensional da coluna vertebral (MM3D), para cálculo das forças internas, articular e muscular resultantes, durante diferentes tarefas de levantamento de carga. O MM3D implementado consiste de um modelo de segmentos articulados (MSA-3D) o qual é composto por dezesseis segmentos rígidos conectados associados a um Modelo de distribuição (MDFMA) o qual fornece as forças musculares (FM) e articulares (FA) resultantes em três níveis da coluna vertebral (superior, médio e inferior). No MSA-3D as forças e momentos proximais líquidos são obtidos a partir da resolução das equações de movimento de Newton-Euler por meio da solução inversa. Com base nas forças e momentos proximais líquidos obtidos do MSA-3D o MDFMA baseado em técnicas de otimização e dados da literatura fornece as FM e FA resultantes na coluna vertebral. A tarefa avaliada consistiu do levantamento de um objeto com 20% da massa corporal do indivíduo em três diferentes técnicas de levantamento. Para registro cinemático foram utilizadas cinco câmeras digitais, com freqüência de amostragem de 25 Hz. O registro cinético foi realizado por meio da utilização de uma plataforma de força, a base de strain-gauges. Os resultados do MM3D implementado foram avaliados por meio da estimativa da acurácia da medida tridimensional obtida pela cinemetria, pela comparação dos resultados do MSA-3D com os valores mensurados pela plataforma de força, pela comparação da FRP e MP calculados pela via superior e inferior do MSA-3D nos segmentos da coluna vertebral e literatura. Os resultados obtidos sugerem uma coerência do MM3D com informações de mensurações diretas e estimativas indiretas obtidas da literatura. Assim o MM3D se mostrou capaz de avaliar e comparar as FM e FA nos três segmentos da coluna vertebral durante diferentes tarefas de levantamento. / Activities performed by the human being can be translated in large internal loads in the most varied body structures. Knowledge of these loads' magnitude may help health area professionals in activities such as prescription of exercises, rehabilitation and prevention of injuries. Internal load's magnitude may be obtained through direct or indirect methods. Direct method stumbles in ethical questions and technology limitations, while indirect analytic method through knowledge of external biomechanics parameters may deduce internal loads. Thus the objective of this study was to implement a tridimensional biomechanical macromodel of the spine (MM3D) to calculate internal forces, joint and muscular resultants, during different tasks of weight lifting. The implemented MM3D consists of an articulated segments model (MSA-3D) composed by sixteen rigid segments connected associated to a distribution Model (MDFMA) that provides resultant muscle (FM) and joint (FA) forces in three levels of the spine (superior, medium and inferior). At the MSA-3D liquid forces and proximal moments are obtained from the resolution of Newton-Euler movement equations through inverse solution. Based in the MSA-3D liquid forces and proximal moments obtained, the MDFMA, based in optimization techniques and data from literature, provides spine resultants FM and FA. The evaluated task consisted of lifting an object with 20% of the subjects' body weight using three different lifting techniques. For kinematics records five digital video cameras were used, with sampling frequency of 25 Hz. Kinetic record was performed using a force platform (strain-gauges based). MM3D implemented results were evaluated through accuracy estimation of the tridimensional measures obtained from kinematics, through comparison of the MSA-3D results and values measured by the force platform, through comparison of spine's segments calculated proximal resultant force and proximal moment calculated through upper and lower ways of MSA-3D and literature. Results suggest a coherence of direct measured information of MM3D and indirect estimative obtained from literature. Thus MM3D showed capable of evaluating and comparing FM and FA at the spine's three segments during different lifting tasks.
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The Importance of Human Population Characteristics in Modeling Aedes aegypti Distributions and Assessing Risk of Mosquito-Borne Infectious DiseasesObenauer, Julie F., Joyner, T. Andrew, Harris, Joseph B. 15 November 2017 (has links)
Background: The mosquito Aedes aegypti has long been a vector for human illness in the Southeastern United States. In the past, it has been responsible for outbreaks of dengue, chikungunya, and yellow fever and, very recently, the Zika virus that has been introduced to the region. Multiple studies have modeled the geographic distribution of Ae. aegypti as a function of climate factors; however, this ignores the importance of humans to the anthropophilic biter. Furthermore, Ae. aegypti thrives in areas where humans have created standing water sites, such as water storage containers and trash. As models are developed to examine the potential impact of climate change, it becomes increasingly important to include the most comprehensive set of predictors possible. Results: This study uses Maxent, a species distribution model, to evaluate the effects of adding poverty and population density to climate-only models. Performance was evaluated through model fit statistics, such as AUC, omission, and commission, as well as individual variable contributions and response curves. Models which included both population density and poverty exhibited better predictive power and produced more precise distribution maps. Furthermore, the two human population characteristics accounted for much of the model contribution-more so than climate variables. Conclusions: Modeling mosquito distributions without accounting for their dependence on local human populations may miss factors that are very important to niche realization and subsequent risk of infection for humans. Further research is needed to determine if additional human characteristics should be evaluated for model inclusion.
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Mapping the Distribution of Atlantic White Cedar throughout southern New Jersey Using Predictive Habitat Distribution ModellingNorlin, Bryanna 27 July 2023 (has links)
No description available.
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Построение модели распределения партнёрских услуг на примере телекоммуникационного оператора : магистерская диссертация / Building a model of distribution of partner services on the example of a telecommunications operatorСвалов, С. А., Svalov, S. A. January 2019 (has links)
Российский рынок телекоммуникаций находится в поиске новых направлений развития, включая партнёрства. Целью магистерской диссертации является разработка и апробация экономической модели распределения партнёрских услуг на примере телекоммуникационного оператора. Анализ основывался на изучении научно-периодической литературы, изучении существующих особенностей телекоммуникационных услуги и специфики распределения услуг. В качестве источников информации использовались нормативно-правовые акты, база публикаций Российского индекса научного цитирования, представленная на ресурсе Elibrary, данные корпоративной статистики по тематике исследования, данные управленческой отчетности и внутренние документы исследуемого предприятия. В ходе написания магистерской диссертации была разработана и апробирована модель распределения партнёрских услуг на примере телекоммуникационного оператора. Использование разработанной модели нацелено на повышение эффективности взаимодействия клиентов, телекоммуникационного оператора и его партнёров. / The purpose of the master's thesis is to develop and test the economic model of distribution of partner services on the example of a telecommunications operator. The analysis was based on the study of scientific and periodical literature, the study of the existing features of telecommunication services and the specifics of the distribution of services. As sources of information we were used legal acts, the database of publications of the Russian Science Citation Index, presented on the Elibrary resource, corporate statistics on the subject of research, management reporting data and internal documents of the enterprise under study. During the work there were developed and tested the model of distribution of partner services on the example of the telecommunications operator. The use of the developed model is aimed at improving the efficiency of interaction between customers, telecommunications operator and its partners.
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Distribution of woodpecker activity relative to wooden utility structure usage in the southeastern United StatesWright, Hannah Chelsea 06 August 2021 (has links)
Woodpeckers are a group of avian species that cause damage to wooden power utility structures. In the southeastern United States, Tennessee Valley Authority (TVA), has accrued an estimated $5 million USD annually from woodpecker damage. Previous work has focused on effectiveness of reactive mitigation and restoration efforts with little investigation of preventative methods. To address this knowledge gap, this study will i) use species distribution model techniques to predict damage suitability across the TVA service area, ii) use Bayesian hierarchical community model techniques to estimate species richness of the woodpecker community in the service area, and iii) recommend target areas for increased preventative measures in the service area. The suitability map indicated that damage was most likely to occur in the southwestern portions of the TVA service area. Woodpecker species richness was stable across the environmental covariate values estimated with 2-3 species found throughout the service area.
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Landscape ecology approaches to Eastern Massasauga Rattlesnake conservationMcCluskey, Eric M. 08 June 2016 (has links)
No description available.
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A Consensus Model for Predicting the Distribution of the Threatened Plant Telephus Spurge (Euphorbia Telephioides)Bracken, Jason 02 December 2016 (has links)
No description available.
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Habitat Suitability Modeling for the Eastern Hog-nosed Snake, 'Heterodon platirhinos', in OntarioThomasson, Victor 26 September 2012 (has links)
With exploding human populations and landscapes that are changing, an increasing number of wildlife species are brought to the brink of extinction. In Canada, the eastern hog-nosed snake, 'Heterodon platirhinos', is found in a limited portion of southern Ontario. Designated as threatened by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), this reptile has been losing its habitat at an alarming rate. Due to the increase in development of southern Ontario, it is crucial to document what limits the snake’s habitat to direct conservation efforts better, for the long-term survival of this species. The goals of this study are: 1) to examine what environmental parameters are linked to the presence of the species at a landscape scale; 2) to predict where the snakes can be found in Ontario through GIS-based habitat suitability models (HSMs); and 3) to assess the role of biotic interactions in HSMs. Three models with high predictive power were employed: Maxent, Boosted Regression Trees (BRTs), and the Genetic Algorithm for Rule-set Production (GARP). Habitat suitability maps were constructed for the eastern hog-nosed snake for its entire Canadian distribution and models were validated with both threshold dependent and independent metrics. Maxent and BRT performed better than GARP and all models predict fewer areas of high suitability when landscape variables are used with current occurrences. Forest density and maximum temperature during the active season were the two variables that contributed the most to models predicting the current distribution of the species. Biotic variables increased the performance of models not by representing a limiting resource, but by representing the inequality of sampling and areas where forest remains. Although habitat suitability models rely on many assumptions, they remain useful in the fields of conservation and landscape management. In addition to help identify critical habitat, HSMs may be used as a tool to better manage land to allow for the survival of species at risk.
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Habitat Suitability Modeling for the Eastern Hog-nosed Snake, 'Heterodon platirhinos', in OntarioThomasson, Victor 26 September 2012 (has links)
With exploding human populations and landscapes that are changing, an increasing number of wildlife species are brought to the brink of extinction. In Canada, the eastern hog-nosed snake, 'Heterodon platirhinos', is found in a limited portion of southern Ontario. Designated as threatened by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), this reptile has been losing its habitat at an alarming rate. Due to the increase in development of southern Ontario, it is crucial to document what limits the snake’s habitat to direct conservation efforts better, for the long-term survival of this species. The goals of this study are: 1) to examine what environmental parameters are linked to the presence of the species at a landscape scale; 2) to predict where the snakes can be found in Ontario through GIS-based habitat suitability models (HSMs); and 3) to assess the role of biotic interactions in HSMs. Three models with high predictive power were employed: Maxent, Boosted Regression Trees (BRTs), and the Genetic Algorithm for Rule-set Production (GARP). Habitat suitability maps were constructed for the eastern hog-nosed snake for its entire Canadian distribution and models were validated with both threshold dependent and independent metrics. Maxent and BRT performed better than GARP and all models predict fewer areas of high suitability when landscape variables are used with current occurrences. Forest density and maximum temperature during the active season were the two variables that contributed the most to models predicting the current distribution of the species. Biotic variables increased the performance of models not by representing a limiting resource, but by representing the inequality of sampling and areas where forest remains. Although habitat suitability models rely on many assumptions, they remain useful in the fields of conservation and landscape management. In addition to help identify critical habitat, HSMs may be used as a tool to better manage land to allow for the survival of species at risk.
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Reliability Cost Model Design and Worth Analysis for Distribution System PlanningYang, Chin-Der 29 May 2002 (has links)
Reliability worth analysis is an important tool for distribution systems planning and operations. The interruption cost model used in the analysis directly affects the accuracy of the reliability worth evaluation. In this dissertation, the reliability worth analysis was dealt with two interruption cost models including an average or aggregated model (AAM), and a probabilistic distribution model (PDM) in two phases. In the first phase, the dissertation presents a reliability cost model based AAM for distribution system planning. The reliability cost model has been derived as a linear function of line flows for evaluating the outages. The objective is to minimize the total cost including the outage cost, feeder resistive loss, and fixed investment cost. The Evolutionary Programming (EP) was used to solve the very complicated mixed-integer, highly non-linear, and non-differential problem. A real distribution network was modeled as the sample system for tests. There is also a higher opportunity to obtain the global optimum during the EP process. In the second phase, the interruption cost model PDM was proposed by using the radial basis function (RBF) neural network with orthogonal least-squares (OLS) learning method. The residential and industrial interruption costs in PDM were integrated by the proposed neural network technique. A Monte-Carlo time sequential simulation technique was adopted for worth assessment. The technique is tested by evaluating the reliability worth of a Taipower system for the installation of disconnected switches, lateral fuses, transformers and alternative supplies. The results show that the two cost models result in very different interruption costs, and PDM may be more realistic in modeling the system.
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