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modeling the nitrogen and phosphorus inputs and outputs of financially optimal irish beef production systems

APPLIED ENGINEERING IN AGRICULTURE 2007年第3期23卷 369-377页

作者： Crosson, P. Rotz, C. A. O'Kiely, P. O'Mara, F. P. Wallace, A. Schulte, R. P. O. USDA ARS University Pk PA 16802 USA TEAGASC Grange Beef Res Ctr Dunsany Meath Ireland Univ Coll Dublin Sch Agr Food Sci & Vet Med Dublin 2 Ireland TEAGASC Johnstown Castle Res Ctr Johnstown Castle Wexford Ireland

Challenges currently faced by beef producers in Ireland include reducing their adverse environmental impact and maintaining farm economic margins. Fertilizers are essential for productive farming but they can be harmful to the environment when inappropriately or excessively applied to crop and pasture land. A linear programming model was used to identify financially optimal strategies for calf-to-stocker and calf-to-finish beef cattle production in high- and low-price market scenarios. The high-price scenario resulted in an increase in gross margin of $1,700 and $13,000 on a 40-ha farm for the stocker and finisher options, respectively. The impacts of these systems on environmental indicators were investigated through farm simulation. In general, the high-price scenarios were more intensive and had greater environmental impacts when compared to the low-price scenarios. Nitrogen leaching losses were quantitatively the most important. environmental indicator on well-drained soils with a maximum annual loss of 72 kg N/ha. Volatilization and denitrification losses of nitrogen (N) were also relatively high where more intensive production was practiced with annual losses of 48 and 23 kg N/ha, respectively, in the most intensive scenario identified. Predicted phosphorus losses were small although annual accumulations in the soil of up to 7.5 kg P/ha may lead to greater losses in the future. On poorly drained soils, volatilization losses were greatest with leaching losses in this case the lowest of the loss pathways investigated. Further reduction in inorganic nitrogen application has the potential to reduce N losses, but predicted concomitant reductions in farm gross margins were also considerable.

关键词： beef production linear programming model nitrogen phosphorus simulation model

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Ordinal optimisation approach for locating and sizing of distributed generation

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IET GENERATION TRANSMISSION & DISTRIBUTION 2009年第8期3卷 713-723页

作者： Jabr, R. A. Pal, B. C. Notre Dame Univ Elect Comp & Commun Engn Dept Zouk Mikhael Zouk Mosbeh Lebanon Univ London Imperial Coll Sci Technol & Med Dept Elect & Elect Engn London SW7 2BT England

This study presents an ordinal optimisation (OO) method for specifying the locations and capacities of distributed generation (DG) such that a trade-off between loss minimisation and DG capacity maximisation is achieved. The OO approach consists of three main phases. First, the large search space of potential combinations of DG locations is represented by sampling a relatively small number of alternatives. Second, the objective function value for each of the sampled alternatives is evaluated using a crude but computationally efficient linear programming model. Third, the top-s alternatives from the crude model evaluation are simulated via an exact non-linear programming optimal power flow (OPF) programme to find the best DG locations and capacities. OO theory allows computing the size s of the selected subset such that it contains at least k designs from among the true top-g samples with a pre-specified alignment probability AP. This study discusses problem-specific approaches for sampling, crude model implementation and subset size selection. The approach is validated by comparing with recently published results of a hybrid genetic algorithm OPF applied to a 69-node distribution network operating under Ofgem (UK) financial incentives for distribution network operators.

关键词： crude model evaluation nonlinear programming distribution network operator distributed power generation Distribution networks load flow ordinal optimisation approach linear programming model distributed generation capacity maximisation linear programming Optimisation techniques alignment probability nonlinear programming optimal power flow

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Trajectory sensitivity analysis on the equivalent one-machine-infinite-bus of multi-machine systems for preventive transient stability control

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IET GENERATION TRANSMISSION & DISTRIBUTION 2015年第3期9卷 276-286页

作者： Xu, Yan Dong, Zhao Yang Zhao, Junhua Xue, Yusheng Hill, David John Univ Newcastle Ctr Intelligent Elect Networks Newcastle NSW 2308 Australia Univ Sydney Sch Elect & Informat Engn Sydney NSW 2006 Australia State Grid Elect Power Res Inst Nanjing Jiangsu Peoples R China Univ Hong Kong Dept Elect & Elect Engn Hong Kong Hong Kong Peoples R China

A new approach for power system transient stability preventive control is proposed by performing trajectory sensitivity analysis on the one-machine-infinite-bus (OMIB) equivalence of multi-machine systems. Exact instability time/angle are determined from the equivalent OMIB power-angle curve;the trajectory sensitivity is calculated at the instability time and the transient stability of the multi-machine system is controlled by constraining the OMIB's angle excursion at the instability time to that of the critical OMIB which corresponds to the marginally stable condition of the system. The required preventive control action (generation rescheduling) can be efficiently solved via a linear programming model with the OMIB trajectory sensitivities-based constraints. Simulation results on the New England 10-machine 39-bus system and a 285-machine and 1648-bus system validate its effectiveness and superiority over previous trajectory sensitivity applications to this problem.

关键词： power system transient stability sensitivity analysis trajectory control preventive maintenance power generation control power generation scheduling linear programming trajectory sensitivity analysis one-machine-infinite-bus equivalence multimachine systems power system transient stability preventive control equivalent OMIB power-angle curve exact instability time determination exact instability angle determination angle excursion generation rescheduling linear programming model OMIB trajectory sensitivities-based constraints New England 10-machine 39-bus system power system operation

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Dealing with petroleum surpluses in Brazil through optimization refining model

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ENERGY STRATEGY REVIEWS 2015年 6卷 80-91页

作者： Ferreira Coelho, Jose Mauro Szklo, Alexandre Univ Fed Rio de Janeiro Alberto Luiz Coimbra Inst Postgrad Studies & Res Energy Planning Program Technol CtrIlha Fundao Block CRoom 211Cidade Univ BR-21949972 Rio De Janeiro RJ Brazil

This study develops a model for linear programming to identify the best option for the use of potential surplus oil in Brazil. The methodology is capable of identifying key international markets that could be served by oil exports and oil products from Brazil, in addition to providing investment in new refineries, in the national refinery installed base or in foreign markets. Through a case study application, it was found that the proposed modeling is capable of adequately representing the real problem of the different possibilities of utilization of surplus crude oil from Brazil. This is a relevant tool to design liquid fuels supply policies in petroleum producing countries. It also helps understanding the better strategy for valuing petroleum surpluses. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： Strategic use of surplus oil Brazilian oil surpluses modeling methodology Oil refinery modeling linear programming model

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Integrated design and evaluation of biomass energy system taking into consideration demand side characteristics

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ENERGY 2010年第5期35卷 2210-2222页

作者： Ren, Hongbo Zhou, Weisheng Nakagami, Ken'ichi Gao, Weijun Ritsumeikan Univ Ritsumeikan Global Innovat Res Org Kita Ku Kyoto 6038577 Japan Ritsumeikan Univ Coll Policy Sci Kyoto 6038577 Japan Univ Kitakyushu Fac Environm Engn Kitakyushu Fukuoka 8080135 Japan

In this paper, a linear programming model has been developed for the design and evaluation of biomass energy system, while taking into consideration demand side characteristics. The objective function to be minimized is the total annual cost of the energy system for a given customer equipped with a biomass combined cooling, heating and power (CCHP) plant, as well as a backup boiler fueled by city gas. The results obtained from the implementation of the model demonstrate the optimal system capacities that customers could employ given their electrical and thermal demands. As an illustrative example, an investigation addresses the optimal biomass CCHP system for a residential area located in Kitakyushu Science and Research Park, Japan. In addition, sensitivity analyses have been elaborated in order to show how the optimal solutions would vary due to changes of some key parameters including electricity and city gas tariffs, biogas price, electricity buy-back price, as well as carbon tax rate. (C) 2010 Elsevier Ltd. All rights reserved.

关键词： Design Evaluation Biomass energy system linear programming model Sensitivity analysis

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OPTIMAL MIX OF TECHNOLOGIES FOR RURAL INDIA - THE LIGHTING SECTOR

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INTERNATIONAL JOURNAL OF ENERGY RESEARCH 1991年第8期15卷 653-665页

作者： SINHA, CS KANDPAL, TC INDIAN INST TECHNOL CTR ENERGY STUDIESNEW DELHI 110016INDIA

Despite the obvious associated social benefits, lighting energy for rural areas of India has been largely ignored. Very little attention has been given either to improving efficiencies of existing lighting technologies or to developing alternatives. Comparing technologies for lighting which are both rational and practical for those living in developing countries is difficult owing to the problems of quantifying the social value and assigning rankings based on the quality of the lighting service provided. In the paper, an attempt is made to develop a framework for evaluating the relative economics of some of the common lighting technologies, and this is then incorporated into a linear programming framework to obtain the least-cost option for satisfying the lighting energy demand of a village subject to various constraints in the context of rural areas.

关键词： RURAL ENERGY LIGHTING DECENTRALIZED ENERGY TECHNOLOGIES linear programming model

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Multiattribute decision making models and methods using intuitionistic fuzzy sets

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JOURNAL OF COMPUTER AND SYSTEM SCIENCES 2005年第1期70卷 73-85页

作者： Li, DF Dalian Naval Acad Dept 2 Dalian 116018 Liaoning Peoples R China

The concept of intuitionistic fuzzy sets is the generalization of the concept of fuzzy sets. The theory of intuitionistic fuzzy sets is well suited to dealing with vagueness. Recently, intuitionistic fuzzy sets have been used to build soft decision making models that can accommodate imprecise information, and two solution concepts about the intuitionistic fuzzy core and the consensus winner for group decision-making have also been developed by other researchers using intuitionistic fuzzy sets. However, it seems that there is little investigation on multicriteria and/or group decision making using intuitionistic fuzzy sets with multiple criteria being explicitly taken into account. In this paper, multiattribute decision making using intuitionistic fuzzy sets is investigated, in which multiple criteria are explicitly considered, several linear programming models are constructed to generate optimal weights for attributes, and the corresponding decision-making methods have also been proposed. Feasibility and effectiveness of the proposed method are illustrated using a numerical example. (C) 2004 Elsevier Inc. All rights reserved.

关键词： fuzzy set intuitionistic fuzzy set multiattribute decision making linear programming model

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Group decision-making based on heterogeneous preference relations with self-confidence

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FUZZY OPTIMIZATION AND DECISION MAKING 2017年第4期16卷 429-447页

作者： Liu, Wenqi Dong, Yucheng Chiclana, Francisco Cabrerizo, Francisco Javier Herrera-Viedma, Enrique Sichuan Univ Sch Business Chengdu 610065 Sichuan Peoples R China De Montfort Univ Fac Technol Leicester Leics England Univ Granada DECSAI Granada Spain

Preference relations are very useful to express decision makers' preferences over alternatives in the process of group decision-making. However, the multiple self-confidence levels are not considered in existing preference relations. In this study, we define the preference relation with self-confidence by taking multiple self-confidence levels into consideration, and we call it the preference relation with self-confidence. Furthermore, we present a two-stage linear programming model for estimating the collective preference vector for the group decision-making based on heterogeneous preference relations with self-confidence. Finally, numerical examples are used to illustrate the two-stage linear programming model, and a comparative analysis is carried out to show how self-confidence levels influence on the group decision-making results.

关键词： Preference relations Self-confidence levels Collective preference vector linear programming model

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modelling green and lean supply chains: An eco-efficiency perspective

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RESOURCES CONSERVATION AND RECYCLING 2017年 120卷 75-87页

作者： Carvalho, Helena Govindan, Kannan Azevedo, Susana G. Cruz-Machado, Virgilio Univ Nova Lisboa Fac Ciencias & Tecnol UNIDEMI Dept Mech & Ind Engn Campus Univ P-2829516 Caparica Portugal Univ Southern Denmark Dept Technol & Innovat Ctr Engn Operat Management Campusvej 55 DK-5230 Odense M Denmark Univ Beira Interior UNIDEMI Polo 4Edificio Ernesto Cruz P-6200209 Covilha Portugal Univ Beira Interior CEFAGE UBI Dept Econ & Business Polo 4Edificio Ernesto Cruz P-6200209 Covilha Portugal

This manuscript proposes a model to support decision making and to help managers identify the best set of green and lean supply chain management practices to improve their eco-efficiency. To attain this objective, a mathematical model based on eco-efficiency concepts is suggested to overcome the trade-offs between lean and green practices. To illustrate the model application, a case study from an automotive supply chain is presented. Some management practices that are instituted for green or lean benefits have opposite effects on the environmental and economic performance of companies. One of the main findings of our study is that not all companies belonging to the same supply chain can be absolutely lean or green. There should be compromises in the individual companies' behaviour so the environmental and economic constraints of the supply chain are both satisfied. The proposed model represents a strategic framework to support the design of eco-efficient supply chains. (C) 2016 Elsevier B.V. All rights reserved.

关键词： Fco-efficiency Lean Green Supply chain linear programming model

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Biofuel mix for cooking in rural areas: Implications for financial viability of improved cookstoves

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BIORESOURCE TECHNOLOGY 1996年第2-3期56卷 169-178页

作者： Rubab, S Kandpal, TC INDIAN INST TECHNOL CTR ENERGY STUDIESNEW DELHI 110016INDIA

An attempt to study the financial implications of replacing a traditional biofuel cookstove with an improved one has been made. The role of several factors influencing the cost of an improved cookstove has been discussed. The capital cost of a popular portable metallic cookstove design in India has been expressed in functional form and the fuel savings have been quantified in terms of two cookstove performance indicators-overall thermal efficiency of a pot-cookstove combination and specific fuel consumption of a cookstove. An LP model is proposed for biofuel resource allocation in a rural setting. Expressions for discounted payback period and the net present value of benefits have been derived Results of some typical numerical calculations indicate that it is financially quire attractive to replace a traditional cookstove with an improved one. The results of the financial analysis are relatively more sensitive to the economic life of the cookstove and price(s) of the biofuel(s). Copyright (C) 1996 Elsevier Science Ltd.

关键词： improved cookstoves portable metallic cookstoves biofuel mix linear programming model thermal efficiency specific fuel consumption financial analysis

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