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A Comparison of Parametric Approximation Techniques to Continuous-Time Stochastic Dynamic Programming Problems AgEcon
Kompas, Tom; Chu, Long.
We compare three parametric techniques to approximate Hamilton-Jacobi-Bellman equations via unidimensional and multidimensional problems. The linear programming technique is very efficient for unidimensional problems and offers a balance of speed and accuracy for multidimensional problems. A comparable projection technique is shown to be slow, but has stable accuracy, whereas a perturbation technique has the least accuracy although its speed suffers least from the curse of dimensionality. The linear programming technique is also shown to be suitable for problems in resource management, including applications to biosecurity and marine reserve design.
Tipo: Journal Article Palavras-chave: Stochastic dynamic programming; Parametric approximation; Perturbation; Projection; Linear programming; Optimal fishing; Marine reserves; Research Methods/ Statistical Methods; Resource /Energy Economics and Policy; C61; C63; Q22.
Ano: 2010 URL: http://purl.umn.edu/95044
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ALLOCATING LAND TO NEW YORK'S CONSERVATION RESERVE ENHANCEMENT PROGRAM TO MAXIMIZE NET ENVIRONMENTAL BENEFITS AgEcon
Jaroszewski, Laura; Poe, Gregory L.; Boisvert, Richard N..
A programming model is used to assess the welfare effects of regional and practice specifications contained in New York State's Draft Conservation Reserve Enhancement Program (CREP) proposal. Net social benefits are nearly 75% lower than options that explicitly account for opportunity costs of production, environmental benefits, and participation response functions. Keywords: benefit cost analysis, conservation programs, participation, linear programming
Tipo: Conference Paper or Presentation Palavras-chave: Benefit cost analysis; Conservation programs; Participation; Linear programming; Environmental Economics and Policy; Land Economics/Use.
Ano: 2000 URL: http://purl.umn.edu/21882
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Allocation of storage yards in management plans in the Amazon by means of mathematical programming. Repositório Alice
SILVA, E. F. da; SILVA, G. F. da; FIGUEIREDO, E. O.; BINOTI, D. H. B.; MENDONÇA, A. R. de; TORRES, C. M. M. E.; PEZZOPANE, J. E. M..
The present study aimed to optimize the location of wood storage yards in forest management for the production of wood in the Brazilian Amazon. The area of forest management studied was 638.17 ha, with 1478 trees selected for harvest with a diameter at breast height of at least 50 cm in accordance with Brazilian legislation. Taking the topography into account-permanent preservation areas, restricted areas, and remaining trees-and using GIS tools, 7896 sites were identified that could be used as wood storage yards. By using mathematical programming techniques, more specifically binary integer linear programming, and based on the classical p-median model, optimal locations for the opening of yards were defined. Four scenarios were proposed combining distance...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Estaleiro; Manejo florestal; Administração florestal; Planejamento florestal; Extração da madeira; Madeira; Armazenamento; Método de otimização; Programação linear; Forest management; Logging; Sort yards; Manejo forestal; Linear programming; System optimization; Explotación forestal; Patios de clasificación; Programación lineal; Optimización de los sistemas.
Ano: 2018 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1088822
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Alocação otimizada de torres para detecção de incêndios florestais. Repositório Alice
AGUIAR, M. O.; LEITE, C. C. C.; VIANA, J. C. C.; MATIAS, H. de B.; SILVA, R. F.; FIGUEIREDO, E. O..
O controle de incêndios florestais através da alocação de torres para a detecção de fumaça é considerado um sistema eficaz para o controle inicial do fogo. O desafio imposto aos pesquisadores é a inserção das torres em posições que otimizem a área de abrangência de cada uma delas. Desta forma, o objetivo deste estudo é propor um novo método heurístico capaz de alocar, de maneira otimizada, as torres em áreas florestais. Conclui-se que o algoritmo implementado foi capaz de alocar as torres respeitando todas as restrições do problema.
Tipo: Artigo em anais de congresso (ALICE) Palavras-chave: Torre de detecção de fumaça; Otimização da área de abrangência; Heurística; Heuristic; Algoritmo heurístico; P-mediana; Bujari (AC); Acre; Amazônia Ocidental; Floresta tropical; Floresta nativa; Incêndio florestal; Controle ambiental; Programação linear; Tropical rain forests; Forest fire management; Smoke; Linear programming; Algorithms; Western Amazon; Bosque tropical húmedo; Manejo de incendios forestales; Humo; Programación lineal; Algoritmos; Amazonia Occidental.
Ano: 2016 URL: http://www.alice.cnptia.embrapa.br/handle/doc/1067265
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Análisis multiobjetivo de la distribución de agua en el sector agrícola de la Comarca Lagunera, México. Colegio de Postgraduados
Jesús Lozano, Luis.
El objetivo de este estudio fue determinar un patrón óptimo de cultivos en el sector agrícola de la Comarca Lagunera considerando de manera simultánea la maximización de la ganancia y la minimización del consumo de agua, dos criterios de optimización usualmente en conflicto. Se formularon dos modelos, uno de programación lineal para replicar el patrón actual de cultivos como base de referencia en el análisis comparativo, y un segundo modelo de programación compromiso que considera de manera simultánea los objetivos en conflicto. Los resultados indican que una estructura productiva más eficiente que la actual, debería considerar el aumento de la superficie de hortalizas ya que estos cultivos consumen sólo el 5% del recurso agua, pero aportan 21% del...
Palavras-chave: Productividad del agua; Programación lineal; Programación compromiso; Water productivity; Linear programming; Compromise programming; Maestría; Economía.
Ano: 2012 URL: http://hdl.handle.net/10521/691
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Analysis and optimization regarding the activity of a Hungarian Pig Sales and Purchase Cooperation AgEcon
Balogh, Peter; Ertsey, Imre; Fenyves, Veronika; Nagy, Lajos.
In many ways, the Hungarian pork chain faces considerable disadvantages when compared to the situation in competing countries. In countries endowed with a modern meat chain, heavy concentration is the rule, but in Hungary decentralization still prevails, although thankfully the chain is not disintegrating even further. In our research we used the operation of co-operatives as a model in terms of a generalized network problem. The model allows the quantification of the number of pigs from given farms to slaughterhouses, the maximum sales revenue, the delivery threshold prices, and an analysis of the impact co-operative members exert on sales revenues.
Tipo: Journal Article Palavras-chave: Pork production; Integration; Network; Linear programming; Demand and Price Analysis; Farm Management; Livestock Production/Industries; Research Methods/ Statistical Methods.
Ano: 2009 URL: http://purl.umn.edu/49192
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Application of decision support methods in preparation for a Hungarian bio-fuel programme AgEcon
Lakner, Zoltan; Vizvari, Bela.
Under current market circumstances and those predictable in the near future, further increasing agricultural production seems to be rather groundless. By utilising agro-ecological conditions more efficiently, one eighth of Hungary’s gasoline demand could be satisfied from maize production, without considerably decreasing current agricultural production for human and animal consumption. For realisation of biofuel programmes a relatively stable socio-economic environment is essential. There is considerable pressure on government from different stakeholders to shift the risks of large-scale investments to the state budget. In the long-run, under the conditions of a liberalised world market the feasibility of biofuel-programmes based on European raw materials,...
Tipo: Journal Article Palavras-chave: Agro-ecological potential; Land usage; Linear programming; Deterministic modelling; Multi-issue actor analysis; Agricultural and Food Policy; Research Methods/ Statistical Methods; Resource /Energy Economics and Policy.
Ano: 2008 URL: http://purl.umn.edu/48087
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Avaliação bioeconômica ex ante de investimentos e planejamento forrageiro em sistemas de produção de bovinos de corte a pasto no Cerrado Repositório Alice
VELOSO, R. F.; BARIONI, L. G.; MALAQUIAS, J. V.; GOMES, E. G.; SILVA, O. D. D. da; CUNHA, M. A. D. da.
Neste estudo, um modelo de programação linear foi construído para estabelecer estratégias de planejamento forrageiro e de investimentos ótimos na renovação das pastagens e na compra de animais, numa fazenda de bovinos de corte, com as opções de cria, de recria e de engorda, localizada em uma região periférica do bioma Cerrado. O objetivo dessa ferramenta é maximizar a receita líquida no final de um período de planejamento de 8 anos com fluxo de caixa mensal. Planilhas eletrônicas foram usadas para construção do modelo e preparação de dados. Em seguida, utilizando-se macros do Visual Basic para aplicativos, geraram-se arquivos no formato MPS para os ?Solvers? do Lindo Systems, do SAS e do LPSolve software. O modelo incorpora custos fixos mensais, provisões...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Estratégia comercial; Modelo bioeconômico; Variável inteira; Integer variables; Programação linear; Bioeconomic models; Linear programming.
Ano: 2013 URL: http://www.alice.cnptia.embrapa.br/handle/doc/1033589
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AVALIAÇÃO ECONÔMICA DE DIFERENTES ESTRATÉGIAS DE GANHO DE PESO DIÁRIO NA TERMINAÇÃO DE BOVINOS EM CONFINAMENTO AgEcon
Resende Filho, Moises de Andrade.
Esse artigo avalia a viabilidade econômica da terminação de bovinos em confinamento para o ano de 2008. Dezessete cenários são simulados considerando-se diferentes ganhos de peso vivo diário para 220 animais, machos castrados, ½ Zebu  ½ Holandês, com peso inicial médio de 354 kg, confinados por 120 dias. Utiliza-se equações capazes de gerar os valores das exigências nutricionais dos animais para cada estratégia de ganho de peso. Os valores calculados das exigência nutricionais parametrizam um modelo de programação linear capaz de minimizar o custo da ração a ser fornecida. Assim, o custo da alimentação dos animais que é o único custo variável do confinamento, é calculado multiplicando-se o custo por kg da ração de custo mínimo pelo consumo voluntário de...
Tipo: Conference Paper or Presentation Palavras-chave: Custos de produção; Programação linear; Minimização do custo da ração; Lucratividade; Production costs; Linear programming; Ration cost minimization; Profitability; Livestock Production/Industries.
Ano: 2008 URL: http://purl.umn.edu/112737
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Beekeepers' honeybee colony selection practice in Tigray, Northern Ethiopia. Repositório Alice
TILAHUN, M.; ABRAHA, Z.; GEBRE, A.; DRUMOND, P. M..
Selection of colonies plays an important role for successful harvesting of desired products from honeybees. The purpose of this study was therefore to assess local knowledge and experience of beekeepers in Tigray regional state of Ethiopia with regard to colony selection and management practices during purchase and multiplication. Respondent selection was carried out based on the existing conventional agroecological zones namely Dega (highland), Kolla (lowland) and Weinadega (midland). Four woredas (districts) from Dega zone, and three from each of Kolla and Weinadega zones were sampled. A total of 185 beekeepers were interviewed to understand the criteria they were using to select colonies. Preference ranking data were indexed using linear programming....
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Tigray; Etiópia; Apicultura; Pequeno produtor; Abelha; Colônia; Seleção; Método de otimização; Programação linear; Apiculture; Beekeepers; Honey bee colonies; Selection criteria; System optimization; Linear programming; Apicultores; Colonias de abejas mielíferas; Criterio de selección; Optimización de los sistemas; Programación lineal.
Ano: 2016 URL: http://www.alice.cnptia.embrapa.br/handle/doc/1043917
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Cost-Minimizing Food Budgets in Ghana AgEcon
Darko, Francis Addeah; Allen, Benjamin; Mazunda, John; Rahimzai, Rafiullah; Dobbins, Craig L..
Replaced with revised version of paper on 01/14/2011.
Tipo: Journal Article Palavras-chave: Developing countries; Nutrition; Minimum costs; Linear programming; Food Consumption/Nutrition/Food Safety.
Ano: 2010 URL: http://purl.umn.edu/96161
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DEMAND ESTIMATION FOR AGRICULTURAL PROCESSING CO-PRODUCTS AgEcon
Wachenheim, Cheryl J.; Novak, Patrick J.; DeVuyst, Eric A.; Lambert, David K..
Co-products of processing agricultural commodities are often marketed through private transaction rather than through public markets or those in which public transaction information is recorded or available. The resulting lack of historical price information prohibits the use of positive time series techniques to estimate demand. Demand estimates for co-products are of value to both livestock producers, who obtain them for use in livestock rations, and processors, who must sell or otherwise dispose of them. Linear programming has long been used, first by researchers and later as a mainstream tool for nutritionists and producers, to formulate least-cost livestock rations. Here it is used as a normative technique to estimate step function demand...
Tipo: Working or Discussion Paper Palavras-chave: Co-products; Demand estimation; Econometrics; Linear programming; Agribusiness.
Ano: 2001 URL: http://purl.umn.edu/23488
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Development of nature-oriented dairy farm systems with an optimization model: the case of ‘Farming for Nature’ in ‘de Langstraat’, the Netherlands AgEcon
Schrijver, R.A.M.; Berentsen, Paul B.M.; Groeneveld, Rolf A.; Corporaal, A.; de Koeijer, T.J..
‘Farming for Nature’, a relatively new policy instrument being tried out in the Netherlands, is evaluated. The concept has been designed to allow dairy farmers to improve nature conservation on their farms. Under the scheme, no manure, fertilizer, or feed – concentrates or roughage - may be imported into farm systems from external sources. The feasibility of such a self-sustaining system and the conditions required for it to deliver the desired results, are explored with a farm-based linear programming model known as FIONA (Farm based Integrated Optimization Model for Nature and Agriculture). The model is explained and applied to ‘de Langstraat’, a region in southern Netherlands. The results show that levels of production under the ‘Farming for Nature’...
Tipo: Journal Article Palavras-chave: Nature management; Dairy farming system; Linear programming; Farm-economics; Farm Management; Land Economics/Use.
Ano: 2006 URL: http://purl.umn.edu/97194
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Energy efficiency improvement for broiler production using non-parametric techniques CIGR Journal
Ebrahimi, Sajjad; Mesri Gundoshmian, Tarahom; Abdi, Reza; Raei Jadidi, Mehri.
The goal of this study was to evaluate the sustainability and efficiency of broiler production with regard to energy consumption in Ardabil province, Iran. To reach the goal, linear programming model and Data Envelopment Analysis (DEA) were employed.  Data were collected from the farmers using a face–to–face questionnaire performed in September–December 2014 period.  The DEA application results showed that the average values of technical, pure technical and scale efficiency scores of producers were 0.949, 0.988 and 0.960, respectively.   Also, energy saving target ratio for broiler production was calculated as 8.33%, indicating that by following the recommendations resulted from this study, about 12316.85 MJ/(1000 bird) of total input energy could be saved...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Energy efficiency; Data Envelopment Analysis; Linear programming; Technical efficiency; Broiler.
Ano: 2016 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3562
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Entscheidungsunterstutzung bei der Gestaltung von Agrarumwelt-programmen: Ein Interaktiver, PC-Gestutzter Programmierungs-ansatz fur Sachsen-Anhalt AgEcon
Kirschke, Dieter; Daenecke, Ernst; Hager, Astrid; Kastner, Kerstin; Jechlitschka, Kurt; Wegener, Stefan.
The increasing importance of measures under the so called "second pillar" of the Common Agricultural Policy of the European Union raises new challenges to decision-makers. The definition and operationalisation of goals as well as the implementation of concrete measures is a complex task. Decisions have to be made on priorities for goals and measures and finally on the allocation of the budget. In this article we demonstrate how policy-making in complex systems can be supported by co-operation between scientists, policy-makers and administrators. Using a participatory computer-aided programming approach the case of improving the agri-environmental programme of Saxony-Anhalt is examined. Based on interactive simulations together with stakeholders and...
Tipo: Working or Discussion Paper Palavras-chave: Agri-environmental policy; Agri-environmental programmes; Decision-making support; Linear programming; Policy consulting; Priority setting; Saxony-Anhalt; Environmental Economics and Policy.
Ano: 2004 URL: http://purl.umn.edu/18820
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Farm and catchment scale effects of managing dry-land salinity with pastoral and woody perennials AgEcon
Finlayson, John D.; Bathgate, Andrew D.; Hoque, Ziaul; Nordblom, Thomas L.; Theiveyanathan, Tivi; Crosbie, Russell; Mitchell, David.
Dry land salinisation is a significant cause of land and water degradation in Australia. Changing land use from annual to perennial crops has been widely proposed as a means to reduce land degradation and increase the productivity of saline land. However, in many areas annual crops are financially more attractive than perennial crops. Increases in perennial crops might also reduce local stream flows with adverse effects on in-stream values. As such salinity control is likely to involve significant tradeoffs between public and private costs and benefits. This paper considers the impact of planting differing areas of pastoral and woody perennials on farm profitability (P), and water (W) and salt (S) exports from the Little River catchment in New South Wales...
Tipo: Conference Paper or Presentation Palavras-chave: Bio-economic modelling; Linear programming; Farm systems; Catchments; Dryland salinity; Land Economics/Use.
Ano: 2007 URL: http://purl.umn.edu/10409
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Farm-level Economic Evaluation of Net Feed Efficiency in Australia’s Southern Beef Cattle Production System: A Multi-period Linear Programming Approach AgEcon
Alford, Andrew R.; Griffith, Garry R.; Cacho, Oscar J..
Selection of beef cattle for increased net feed efficiency is a current major focus for research. At present the trait seems to be more apparent in Australia’s southern beef production system which is dominated by mixed farming enterprises. Farm-level evaluation of net feed efficiency should take account of the farming system for which it is proposed along with the dynamic nature of genetic selection. Gross margin, linear programming and multi-period linear programming approaches to evaluation of the trait at the farm-level using a representative farm are compared. Implications of the trait for researchers and beef producers are identified
Tipo: Conference Paper or Presentation Palavras-chave: Farm-level evaluation; Genetic traits; Linear programming; Farm Management.
Ano: 2003 URL: http://purl.umn.edu/57826
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Financing Agri-Environmental Programs in Poland: The Importance of Regional Preferences AgEcon
Ziolkowska, Jadwiga; Kirschke, Dieter.
The main objective of the paper is to study the importance of regional preferences in financing agri-environmental programs. The analysis is based on results of a case study conducted in South-eastern Poland. As environmental protection in agriculture is complex and often considered in political strategies, it is worth analyzing the differences in perception of the respective environmental objectives from a regional perspective. Taking into account natural conditions and the economic situation in agriculture in the voivodship Podkarpackie, the question is, how regional objectives could be achieved effectively with a given budget. Using linear programming, we discuss in this paper, how regional preferences would guide budget allocation.
Tipo: Conference Paper or Presentation Palavras-chave: Agri-environmental programs; Environmental objectives; Linear programming; Budget allocation; Poland; Environmental Economics and Policy; Q14; Q57; C6.
Ano: 2006 URL: http://purl.umn.edu/25658
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Food vs. Wood: Dynamic Choices for Kenyan Smallholders AgEcon
Peralta, Maria Alexandra; Swinton, Scott M..
Natural resource management
Tipo: Conference Paper or Presentation Palavras-chave: Agroforestry; Eucalyptus; Food security; Kenya; Linear programming; Smallholder agriculture; Whole farm model; Crop Production/Industries; International Development; Production Economics; Resource /Energy Economics and Policy; O13; Q12.
Ano: 2009 URL: http://purl.umn.edu/49401
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How can dairies maximize their profits and properly remunerate their dairy farmers? Scientia Agricola
Meneghini,Rafael Cedric Möller; Cassoli,Laerte Dagher; Martines Filho,João Gomes; Xavier,Carlos Eduardo Osório; Santos,Marcos Veiga dos; Caixeta Filho,José Vicente; Natel,Andressa Santanna; Machado,Paulo Fernando.
ABSTRACT The current pricing process of raw milk in Brazil discourages producers from improving milk composition, which affects both yield and quality of dairy products. Furthermore, small and medium-sized dairies face great difficulties when it comes to planning production. Thus, a linear programming model was developed to price the raw milk and determine the optimal mix (combination of quantities) of dairy products that maximizes total contribution margin (TCM) under daily scenarios of high (January) and low (July) raw milk supplies (summer and winter, respectively) by comparing optimal solutions with actual results. The TCM of optimal and actual mixes were higher in January due to the greater availability of raw material. Packaging was a limiting factor...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Contribution margin; Dairy products; Linear programming; Milk components; Milk pricing.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162016000100051
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