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	Provedor de dados 31 (22) 5 (3) 52 (1) Autor Kim, C.S. (3) Mairet, Francis (3) Richards, Timothy J. (3) Cacho, Oscar J. (2) Ellsworth, Peter (2) Gouze, Jean-luc (2) Lewandrowski, Jan (2) Lyon, Kenneth S. (2) Naranjo, Steve (2) Schaible, Glenn D. (2) Sedjo, Roger A. (2) Tronstad, Russell (2) Yegorov, Ivan (2) Bayen, Térence (1) Burnett, Kimberly M. (1) Börner, Jan (1) De Jong, Hidde (1) Doole, Graeme J. (1) Eagle, Alison J. (1) Eiswerth, Mark E. (1) Mais... Palavra-chave Optimal control (26) Resource /Energy Economics and Policy (10) Environmental Economics and Policy (9) Invasive species (4) Bioeconomics (3) Crop Production/Industries (3) Q57 (3) Bacterial growth (2) Externalities (2) Hazard function (2) Land Economics/Use (2) Permits (2) Public Economics (2) Q20 (2) Q23 (2) Risk and Uncertainty (2) Spatial-temporal model (2) Adaptive management (1) Advertising (1) Australia (1) Mais... Tipo do documento Conference Paper or Presentation (9) Journal Article (6) Working or Discussion Paper (6) Text (3) Info:eu-repo/semantics/article (1) Presentation (1) Mais... Ano 2020 (1) 2019 (1) 2018 (1) 2012 (1) 2011 (2) 2010 (6) 2009 (3) 2007 (1) 2006 (1) 2005 (3) 2004 (1) 2002 (1) 2001 (1) 2000 (1) 1996 (2) Mais... País United States (22) France (3) Brazil (1) Idioma Inglês (26)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 26 Primeira ... 1 2 ... Última Variational calculus (optimal control) applied to the optimization of the enzymatic synthesis of ampicillin 52 Ribeiro,Marcelo Perencin de Arruda; Giordano,Roberto de Campos. In this work, optimal control techniques were used to optimize the feed of reactants during the enzymatic synthesis of ampicillin in a semi-batch reactor. Simulation results showed that a semi-batch integrated reactor (with product crystallization) might achieve 88% 6-APA (6-aminepenicillanic acid) conversion and 92% of PGME (phenylglycine methyl ester) yield, with a productivity between 3.5 and 5.5 mM min-1. Tipo: Info:eu-repo/semantics/article Palavras-chave: Synthesis of beta-lactam antibiotics; Fed-batch reactor optimization; Optimal control. Ano: 2005 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132005000400003 Parameter Estimation for Dynamic Resource Allocation in Microorganisms: A Bi-level Optimization Problem 5 Mairet, Francis; Bayen, Térence. Given their key roles in almost all ecosystems and in several industries, understanding and predicting microorganism growth is of utmost importance. In compliance with evolutionary principles, coarse-grained or genome-scale models of microbial growth can be used to determine optimal resource allocation scheme under dynamic environmental conditions. Resource allocation approaches have given important qualitative results, but it still remains a gap towards quantitiative predictions. The first step in this direction is parameter calibration with experimental data. But fitting these models results in a bi-level optimization problem, whose numerical resolution involves complex optimization issues. As a case study, we present here a coarse-grained model... Tipo: Text Palavras-chave: Bi-level optimization; Optimal control; Pontryagin’s principle; Chattering; Microbial growth; Microalgae. Ano: 2020 URL: https://archimer.ifremer.fr/doc/00690/80163/83228.pdf Optimal feedback strategies for bacterial growth with degradation, recycling, and effect of temperature 5 Yegorov, Ivan; Mairet, Francis; Gouze, Jean-luc. Mechanisms of bacterial adaptation to environmental changes are of great interest for both fundamental biology and engineering applications. In this work, we consider a continuous-time dynamic problem of resource allocation between metabolic and gene expression machineries for a self-replicating prokaryotic cell population. In compliance with evolutionary principles, the criterion is to maximize the accumulated structural biomass. In the model, we include both the degradation of proteins into amino acids and the recycling of the latter (ie, using as precursors again). On the basis of the analytical investigation of our problem by Pontryagin's maximum principle, we develop a numerical method to approximate the switching curve of the optimal feedback control... Tipo: Text Palavras-chave: Bacterial growth; Chattering regime; Effect of temperature; Feedback strategy; Optimal control; Pontryagin's maximum principle; Protein degradation; Recycling; Resource allocation; Singular regime; Switching curve. Ano: 2018 URL: https://archimer.ifremer.fr/doc/00434/54592/56057.pdf Optimal control of bacterial growth for the maximization of metabolite production 5 Yegorov, Ivan; Mairet, Francis; De Jong, Hidde; Gouze, Jean-luc. Microorganisms have evolved complex strategies for controlling the distribution of available resources over cellular functions. Biotechnology aims at interfering with these strategies, so as to optimize the production of metabolites and other compounds of interest, by (re)engineering the underlying regulatory networks of the cell. The resulting reallocation of resources can be described by simple so-called self-replicator models and the maximization of the synthesis of a product of interest formulated as a dynamic optimal control problem. Motivated by recent experimental work, we are specifically interested in the maximization of metabolite production in cases where growth can be switched off through an external control signal. We study various optimal... Tipo: Text Palavras-chave: Optimal control; Nonlinear dynamical systems; Mathematical modelling; Bacterial growth; Biotechnology. Ano: 2019 URL: https://archimer.ifremer.fr/doc/00486/59791/63028.pdf A Dynamic Optimisation Model of Weed Control 31 Cacho, Oscar J.; Jones, Randall E.. It is argued in this paper that static approaches to weed management, where the benefits and costs are only considered within a single season, are inappropriate for assessing the economic benefits of weed control technologies. There are carryover effects from weed management as weeds that escape control in one season may reproduce and replenish weed populations in following seasons. Consequently, it is appropriate to view weed control in the context of a resource management problem where the goal is to determine the optimal inter-temporal level of weed control that maximises economic benefits over some pre-determined period of time. A dynamic optimisation model for weed control is presented. Using the tools of comparative static analysis and Pontryagin's... Tipo: Working or Discussion Paper Palavras-chave: Weed control; Resource economics; Optimal control; Dynamic programming; Wild oats; Farm Management. Ano: 2000 URL: http://purl.umn.edu/12902 Market-Based Instruments for the Optimal Control of Invasive Insect Species: B. Tabaci in Arizona 31 Richards, Timothy J.; Ellsworth, Peter; Tronstad, Russell; Naranjo, Steve. Invasive insect species represent perhaps one of the most significant potential sources of economic risk to U.S. agricultural production. Private control of invasive insect species is likely to be insufficient due to negative externality and weaker-link public good problems. In this study, we compare a system of Pigouvian taxes with tradable permits for invasive species control. While the emissions control literature shows that taxes are preferred to permits under cost uncertainty, invasive species control involves correlated cost and benefit uncertainty, so we expect a quantity-based system to be preferred. Monte Carlo simulations of optimal steady-state outcomes confirm our expectations. Tipo: Conference Paper or Presentation Palavras-chave: Externalities; Invasive species; Optimal control; Permits; Spatial-temporal model; Taxes.; Environmental Economics and Policy; Public Economics; Risk and Uncertainty; H23; L51; Q28; Q57.. Ano: 2010 URL: http://purl.umn.edu/61189 Permanence of Carbon Sequestered in Forests under Uncertainty 31 Kim, C.S.; Lewandrowski, Jan; Sands, Ronald D.; Johansson, Robert C.. In this paper we examine the issue of permanence in the context of sequestering carbon through afforestation. We develop a dynamic nested optimal control model of carbon sequestration associated with the decision to afforest a tract of land given there are uncertainties associated with fire and insect/disease hazards. Conceptually, these potential hazards are similar in that their occurrence at any time t is uncertain and landowners can take specific actions – although generally different actions - in any time period t to reduce the probability of sustaining losses related to them. The hazards differ, however, in that fire represents a large loss in carbon at a moment in time, while insect/disease infestations are more likely to be reflected in a period... Tipo: Conference Paper or Presentation Palavras-chave: Carbon sequestration; Uncertainty; Optimal control; Hazard function; Forestry; Permanence; Environmental Economics and Policy; Land Economics/Use. Ano: 2011 URL: http://purl.umn.edu/103565 Timber Supply Model 96: A Global Timber Supply Model with a Pulpwood Component 31 Sedjo, Roger A.; Lyon, Kenneth S.. This study involves an update of our earlier Timber Supply Model, which was fully developed in our book, The Adequacy Of Global Timber Supply by Sedjo and Lyon (1990), published by Resources for the Future. The new version, called Timber Supply Model 1996 (TSM96), uses an economic market supply/demand approach to project an intertemporal time path of the world's price and output level of industrial wood. As did the original TSM, the TSM96 provides projections of the time path of the equilibrium output levels of the several regions into which the world has been subdivided. A major new feature of TSM96 is that industrial wood, treated as homogeneous in the earlier study, has be subdivided into two different wood types -- pulpwood and solidwood. The supply of... Tipo: Working or Discussion Paper Palavras-chave: Timber models; Markets; Optimal control; Projections; Timber supply; Resource /Energy Economics and Policy; C62; Q21; Q23. Ano: 1996 URL: http://purl.umn.edu/10696 Multiregional Invasive Species Management: Theory and an Application to Florida's Exotic Plants 31 Kim, C.S.; Lee, Donna J.; Schaible, Glenn D.; Vasavada, Utpal. This research develops a multiregional optimal control model that incorporates regional allocation of a public budget for controlling invasive plants when regionally differential recreation demand functions and species control costs are present. Our equimarginal condition for optimal budget allocation equates the relative marginal economic benefits per dollar spent across regions. The model was applied to Florida Public Conservation Land regions, and results indicate that the magnitude of an annual management budget affects its distribution among species management regions, but the size of the intrinsic growth rate does not affect the pattern of budget allocation among regions. Tipo: Journal Article Palavras-chave: Budget allocation; Equimarginal condition; Florida invasive species; Invasive plants; Optimal control; B41; C02; Q51; Q57. Ano: 2007 URL: http://purl.umn.edu/37141 Dynamic Programming and Learning Models for Management of a Nonnative Species 31 Eiswerth, Mark E.; van Kooten, G. Cornelis; Lines, Jeff M.; Eagle, Alison J.. Nonnative invasive species result in sizeable economic damages and expensive control costs. Because dynamic optimization models break down if controls depend in complex ways on past controls, non-uniform or scale-dependent spatial attributes, etc., decision support systems that allow learning may be preferred. We compare three models of an invasive weed in California’s grazing lands: (1) a stochastic dynamic programming model, (2) a reinforcement-based, experience-weighted attraction (EWA) learning model, and (3) an EWA model that also includes stochastic forage growth and penalties for repeated application of environmentally harmful control techniques. Results indicate that EWA learning models may be appropriate for invasive species management. Tipo: Working or Discussion Paper Palavras-chave: Invasive weed species; Optimal control; Adaptive management; Environmental Economics and Policy; C73; Q57. Ano: 2005 URL: http://purl.umn.edu/37015 Optimal Control of Brucellosis in Bison in the Yellowstone National Park Area 31 Xie, Fang; Horan, Richard D.. Brucellosis is a highly infectious bacterial disease that causes infected females to abort their calves. It has caused devastating losses to U.S. farmers over the last century. The only known focus of Brucellosis left in the nation is wildlife such as bison and elk in the Greater Yellowstone Area. Vaccination and test-and-slaughter have been applied to brucellosis management in bison, and there has been discussion that a combination of both could potentially eradicate the disease in the Yellowstone National Park. However, there is no study on how to allocate resources between the two actions. This paper investigates the optimal allocation of these two selective management options, in a bioeconomic framework, when there are both existence and recreational... Tipo: Conference Paper or Presentation Palavras-chave: Bioeconomics; Brucellosis; Disease ecology; Epidemiology; Optimal control; Susceptible-infected-recovered (SIR) model; Resource /Energy Economics and Policy. Ano: 2010 URL: http://purl.umn.edu/61334 Modelling Environmental Effects of Agriculture: The Case of Organic Rye and Grey Partridge 31 Miettinen, Antti; Huhtala, Anni. Our optimal control model identifies economic reasons as to why farmland bird populations have dramatically declined in modern agricultural landscapes. By integrating recreational wildlife values into farm level decision-making on arable crop choice and herbicide use, we derive those economic instruments needed for creating suitable conditions for game bird species on farmland. Based on the Finnish data available on the grey partridge (Perdix perdix), we illustrate how the optimal acreage subsidy for organically-grown areas, herbicide tax rates and the hunting licence fee could be estimated in monetary terms. Finally, we discuss the benefits and costs of cultivating organic cereals which will enhance preservation of the grey partridge. Tipo: Conference Paper or Presentation Palavras-chave: Environmental benefits; Grey partridge; Herbicides; Optimal control; Rye; Environmental Economics and Policy; Q57; Q18; H41. Ano: 2005 URL: http://purl.umn.edu/24462 A Practical Algorithm for Multiple-Phase Control Systems in Agricultural and Natural Resource Economics 31 Doole, Graeme J.. Many important problems in agricultural and natural resource economics concern an intertemporal choice between alternate dynamic systems. This significance has motivated a theoretical literature generalizing the necessary conditions of Optimal Control Theory to multiple-phase problems. However, gaining detailed insight into their practical management is difficult because general numerical solution methods are not available. This paper resolves this deficiency through the development of a flexible and efficient computational algorithm based on a set of necessary conditions derived for finite-time, multiple-phase systems. Its effectiveness is demonstrated in an application to a nontrivial crop rotation problem. Tipo: Journal Article Palavras-chave: Crop management; Multiple-phase systems; Optimal control; Crop Production/Industries; Resource /Energy Economics and Policy. Ano: 2009 URL: http://purl.umn.edu/50082 Market-Based Instruments for the Optimal Control of Invasive Insect Species: B. Tabaci in Arizona 31 Richards, Timothy J.; Ellsworth, Peter; Tronstad, Russell; Naranjo, Steve. Invasive insect species represent perhaps one of the most significant potential sources of economic risk to U.S. agricultural production. Private control of invasive insect species is likely to be insufficient due to negative externality and weaker-link public good problems. In this study, we compare a system of Pigouvian taxes with tradable permits for invasive species control. While the emissions control literature shows that taxes are preferred to permits under cost uncertainty, invasive-species control involves correlated cost and benefit uncertainty. Hence, we expect a quantity-based system to be preferred. Monte Carlo simulations of optimal steady-state outcomes confirm our expectations. Tipo: Journal Article Palavras-chave: Externalities; Invasive species; Optimal control; Permits; Spatial-temporal model; Taxes; Crop Production/Industries; Resource /Energy Economics and Policy. Ano: 2010 URL: http://purl.umn.edu/97852 Safe Minimum Standards in Dynamic Resource Problems -- Conditions for Living on the Edge of Risk 31 Margolis, Michael; Naevdal, Eric. Safe Minimum Standards (SMSs) have been advocated as a policy rule for environmental problems where uncertainty about risks and consequences are thought to be profound. This paper explores the rationale for such a policy within a dynamic framework and derives conditions for when SMSs can be summarily dismissed as a policy choice and for when SMSs can be defended as an optimal policy based on standard economic criteria. We have determined that these conditions can be checked with quite limited information about damages and risks. In order to analyze the SMSs in a dynamic setting, we have developed a method for solving optimal control problems where the state space is divided into risky and non-risky subsets. Tipo: Working or Discussion Paper Palavras-chave: Safe minimum standards; Optimal control; Critical zone; Threshold effects; Mixed risk spaces; Risk and Uncertainty; C61; Q20; Q30. Ano: 2004 URL: http://purl.umn.edu/10568 Induced-Innovation and Invasive Species Management 31 Kim, C.S.; Schaible, Glenn D.; Lewandrowski, Jan. Public policy for managing invasive species has largely focused on preventive measures prior to detection (stage 1) and on the use of chemical/mechanical or biological control measures after the establishment and dispersion of the invasive species (stage 2). Optimal management policy depends both on the initial stock of the invasive species and on the costs associated with conventional control measures. However, little attention has focused on how an induced technology such as Bt corn and Bt cotton is developed and adopted by farmers (stage 3), or how it affects the manageability of economic and ecological damages from an invasive species. This analysis evaluates the optimal allocation of management resources between preventive and control measures for... Tipo: Conference Paper or Presentation Palavras-chave: Invasive species; Preventive measures; Control measures; Induced technology; Hazard function; Optimal control; Comparative dynamic analysis; Environmental Economics and Policy; Production Economics. Ano: 2010 URL: http://purl.umn.edu/60985 Heterogeneity among agent types and second-best management for non-market ecological services 31 Fenichel, Eli P.. Second-best management affects different agent types differently, and heterogeneity among agents may create instances when only second best management is feasible. Capital-theoretic bioeconomic modeling often has imposed representative agent assumptions that may not capture this heterogeneity. Interactions between agent heterogeneity and second-best management have received little attention. Such heterogeneity is particularly important when management actions do not directly affect extensive margin decisions. We employ a microparameter model in a dynamic bioeconomic model to incorporate agent heterogeneity and intensive and extensive margin decisions for a nonmarket good, recreational fishing. The model yields qualitatively different management... Tipo: Conference Paper or Presentation Palavras-chave: Entry-exit; Microparameter; Bioeconomics; Recreational fishing; Landing limits; Optimal control; Resource /Energy Economics and Policy; Q20; Q22; Q26. Ano: 2009 URL: http://purl.umn.edu/48995 The Economics of Commonly Owned Groundwater When User Demand Is Perfectly Inelastic 31 Wang, Chenggang; Segarra, Eduardo. This paper provides a theoretical analysis of the common-pool resource dilemma in extracting nonrenewable groundwater resources when water demand is perfectly inelastic. It complements the existing theory of groundwater use, which assumes away the possibility of demand perfect inelasticity. Under perfectly inelastic water demand, the common-pool resource dilemma is by-passed if groundwater users are equally productive in water use. If they are not, a new type of inefficiency can arise due to the lack of a rationing mechanism on the basis of productivity. Our analysis suggests that groundwater management research should pay more attention to water demand elasticity and productivity heterogeneity. Tipo: Journal Article Palavras-chave: Common-pool resources; Groundwater extraction; Groundwater management; Groundwater use; Irrigation water demand; Optimal control; Pumping externality; Water demand elasticity; Resource /Energy Economics and Policy. Ano: 2011 URL: http://purl.umn.edu/105533 The effect of storms on Optimal Beach Managenent 31 Gopalakrishnan, Sathya; McNamara, Dylan; Smith, Martin D.; Murray, Brad. Tipo: Presentation Palavras-chave: Beach Nourishment; Climate Change; Storms; Optimal control; Environmental Economics and Policy; Resource /Energy Economics and Policy; Q54. Ano: 2012 URL: http://purl.umn.edu/124375 Approximating optimal numerical solutions to bio-economic systems: How useful is simulation-optimization? 31 Börner, Jan; Higgins, Steven Ian; Scheiter, Simon; Kantelhardt, Jochen. For applications in agricultural economics, complex ecological systems are often oversimplified to the extent that ecologists rarely consider model results valid. Recursive optimization of complex systems represents an alternative, but requires strong assumptions regarding time preference and uncertainty. In this paper we explore the implications of merely approximating “true” optima of complex dynamic optimization problems using a technique called simulation-optimization. We develop a standard discrete renewable resource use problem and solve it numerically using both simulation-optimization and non-linear mathematical programming. We subsequently introduce non-linearity and uncertainty and graphically compare the performance of simulation-optimization... Tipo: Conference Paper or Presentation Palavras-chave: Optimal control; Simulation; Ecological economic systems; Interdisciplinary modeling; Environmental Economics and Policy; Research Methods/ Statistical Methods. Ano: 2009 URL: http://purl.umn.edu/51407 Registros recuperados: 26 Primeira ... 1 2 ... Última

Empresa Brasileira de Pesquisa Agropecuária - Embrapa Todos os direitos reservados, conforme Lei n° 9.610 Política de Privacidade Área restrita		Embrapa Parque Estação Biológica - PqEB s/n° Brasília, DF - Brasil - CEP 70770-901 Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC: https://www.embrapa.br/fale-conosco