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Registros recuperados: 12 | |
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Alves, Alexandre Florindo; Serra, Marco Henrique. |
O presente estudo tem como objetivo, usando simulações, analisar as operações de hedge com contratos de boi gordo da Bolsa de Mercadorias & Futuros (BM&F). As simulações compreenderam o período de 2001 a 2006, sendo que em todos os anos os contratos simulados são do mesmo vencimento, outubro com entrada na operação no mês de março, em três estados diferentes: São Paulo, Paraná e Mato Grosso do Sul. A estratégia de utilização do mercado futuro mostrou-se viável, desde que acompanhada do conhecimento de fatores que interferem no mecanismo de comercialização: o comportamento da base e do risco de base em cada região. O conhecimento e o acompanhamento destes fatores, através dos anos, tem fundamental importância na tomada de decisão para operações no... |
Tipo: Conference Paper or Presentation |
Palavras-chave: Boi gordo; Contratos futuros; Simulações; Hedge; Live cattle; Futures contracts; Simulations; Hedge; Livestock Production/Industries; Marketing; Risk and Uncertainty. |
Ano: 2008 |
URL: http://purl.umn.edu/102471 |
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Meynard, Christine N.; Kaplan, David; Leroy, Boris. |
Liu et al. (2018) used a virtual species approach to test the effects of outliers on species distribution models. In their simulations, they applied a threshold value over the simulated suitabilities to generate the species distributions, suggesting that using a probabilistic simulation approach would have been more complex and yield the same results. Here, we argue that using a probabilistic approach is not necessarily more complex and may significantly change results. Although the threshold approach may be justified under limited circumstances, the probabilistic approach has multiple advantages. First, it is in line with ecological theory, which largely assumes non‐threshold responses. Second, it is more general, as it includes the threshold as a... |
Tipo: Text |
Palavras-chave: ENM; Observation errors; Outliers; Prevalence; Probabilistic approach; Sample bias; Simulations; Species distribution models; Virtual ecology; Virtual species. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00501/61309/64868.pdf |
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Cunha,Gisele C. de A.; Lopes Neto,José P.; Furtado,Dermeval A.; Borges,Valéria P.; Freire,Elias A.; Nascimento,José W. B. do. |
ABSTRACT Negative pressure ventilation in poultry houses has been used to enable the correction of their internal microclimates, and studies point to the heterogeneous distribution of air along the aviaries and the inadequacy of the environmental variables to the recommended ranges for thermal comfort of adult birds, especially in the hottest hours of the day. This study aimed to diagnose the facilities of a poultry house in the state of Paraíba, Brazil, regarding the distribution of environmental variables and thermal comfort; develop a computational model and validate it for Computational Fluid Dynamic - CFD simulations. Air temperature (Tair), air relative humidity (RH) and air velocity (Vair) data allowed characterizing the internal environment by... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Thermal comfort; Thermal index; Simulations. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662019001000761 |
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Miller, Brian W.; Department of the Interior North Central Climate Science Center, Natural Resource Ecology Laboratory, Colorado State University; brian.miller@colostate.edu; Morisette, Jeffrey T.; Department of the Interior North Central Climate Science Center, Natural Resource Ecology Laboratory, Colorado State University; U.S. Geological Survey; morisettej@usgs.gov. |
Developing resource management strategies in the face of climate change is complicated by the considerable uncertainty associated with projections of climate and its impacts and by the complex interactions between social and ecological variables. The broad, interconnected nature of this challenge has resulted in calls for analytical frameworks that integrate research tools and can support natural resource management decision making in the face of uncertainty and complex interactions. We respond to this call by first reviewing three methods that have proven useful for climate change research, but whose application and development have been largely isolated: species distribution modeling, scenario planning, and simulation modeling. Species distribution... |
Tipo: Peer-Reviewed Synthesis |
Palavras-chave: Agent-based modeling; Complex-adaptive systems; Natural resource management; Scenario planning; Simulations; Species distribution modeling; State-and-transition modeling. |
Ano: 2014 |
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Herrera Ayala, Lucila. |
En la actualidad la trazabilidad en el mercado de carne de bovino se está tornando una herramienta trascendente, principalmente para los países que se han visto afectados por la Encefalopatía Espongiforme Bovina (EEB) u otra enfermedad zoonótica. Esta medida se está dando en respuesta a los requerimientos de los consumidores, quienes cada vez solicitan más información sobre el producto que están adquiriendo, debido a estas exigencias los principales exportadores de carne de bovino tienen que recurrir a esta nueva tendencia, de lo contrario perderían mercados y se vería gravemente afectada su economía. La presente investigación tuvo como finalidad evaluar la posible implementación de un sistema de trazabilidad en el mercado de carne de bovino en... |
Tipo: Tesis |
Palavras-chave: Encefalopatía espongiforme bovina; Simulaciones; Valor del inventario; Maestría; Economía; Bovine spongiform encephalopathy; Simulations; Cattle value. |
Ano: 2009 |
URL: http://hdl.handle.net/10521/1305 |
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Parry, Ian W.H.. |
Certain types of expenditure--e.g. mortgage interest and medical insurance- receive favorable tax treatment and are effectively subsidized relative to other (non-tax-favored) expenditures. Labor taxes (e.g. income taxes) can therefore produce efficiency losses by distorting the allocation of consumption, in addition to distorting the labor market. Using evidence on the responsiveness of taxable income to changes in tax rates, a seminal study by Feldstein (1999) estimates that the marginal excess burden of taxation (MEB) could exceed unity, when the effects of tax deductions are taken into account. This is several times larger than in previous studies of the MEB that focus exclusively on labor market effects. This paper develops a "disaggregated" approach... |
Tipo: Working or Discussion Paper |
Palavras-chave: Welfare costs; Tax system; Tax deductions; Simulations; Political Economy; H21; H43. |
Ano: 1999 |
URL: http://purl.umn.edu/10801 |
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Meynard, Christine N.; Leroy, Boris; Kaplan, David. |
Species distribution models (SDMs) have become one of the major predictive tools in ecology. However, multiple methodological choices are required during the modelling process, some of which may have a large impact on forecasting results. In this context, virtual species, i.e., the use of simulations involving a fictitious species for which we have perfect knowledge of its occurrence‐environment relationships and other relevant characteristics, have become increasingly popular to test SDMs. This approach provides for a simple virtual ecologist framework under which to test model properties, as well as the effects of the different methodological choices, and allows teasing out the effects of targeted factors with great certainty. This simplification is... |
Tipo: Text |
Palavras-chave: Artificial species; Environmental niche models; Niche; Simulations; Species distribution modelling; Virtual ecologist. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00501/61308/64864.pdf |
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Registros recuperados: 12 | |
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