Existing cropping systems in Northern Zambia cause deforestation and soil degradation. To reduce the environmental problems, the potential of alley cropping and pigeon peas replacing the existing cropping systems was ...
详细信息
Existing cropping systems in Northern Zambia cause deforestation and soil degradation. To reduce the environmental problems, the potential of alley cropping and pigeon peas replacing the existing cropping systems was analyzed by the use of multi-objective programming models of peasant households. The models were formulated based on the theories of Chayanov and Nakajima which are suitable under conditions of imperfect labour markets. Risk was incorporated in the models in relation to weather and fertilizer supply. The models provide an opportunity to relate key characteristics of new technologies to key characteristics of peasants' preferences and resource constraints. The models may also be used to identify minimum performance levels required for new technologies to be found acceptable. Models of a small male-headed household are presented under varying conditions: for high and low population densities, with and without fertilizer subsidies, and for households with and without access to off-farm employment under high population density conditions. The analysis showed that the alley cropping technology is very unlikely to replace the chitemene system where there is still sufficient woodland for its continuation. The technology may have higher potential in more densely populated areas, where more intensive forms of agriculture are practised and where there is access to inputs such as lime and fertilizer. The removal of fertilizer subsides as a result of the Structural Adjustment Programs, may favour alley cropping because this technology may increase the efficiency of fertilizer use and reduce the need for nitrogenous fertilizers. The potential of the technology depends very much on the management level and location-specific performance of the trees. The pigeon pea technology has high potential if it is accepted as food since it has a very favourable yield per unit of labour, requires no monetary inputs, and can grow in very poor soils. Pigeon pea also has potential a
We show by counterexample that one of the results in the paper "On Pareto optima, the Fermat-Weber problem, and polyhedral gauges", by R. Durier, Mathematical programming 47 (1990), does not hold. The stated...
详细信息
We show by counterexample that one of the results in the paper "On Pareto optima, the Fermat-Weber problem, and polyhedral gauges", by R. Durier, Mathematical programming 47 (1990), does not hold. The stated characterization of properly efficient points for a scalar location problem is only true in dimension 1 and 2. For higher dimensions, the property stated is necessary, but not sufficient.
We present a method of obtaining some classes of generalized V-univex type-I multiobjective optimization problems starting from classes of problems involving functions defined on R". In this way, examples of mult...
详细信息
ISBN:
(纸本)9789955282839
We present a method of obtaining some classes of generalized V-univex type-I multiobjective optimization problems starting from classes of problems involving functions defined on R". In this way, examples of multiobjective optimization problems given in previous articles, which are mentioned in the references, can be reformulated as optimization problems with generalized vectorial functions and having the same properties as the original ones.
Rural-urban land conversion is an inevitable phenomenon in urbanization arid industrialization. And the decision-making issue about this conversion is multi-objective because the social decision maker (the whole of c...
详细信息
Rural-urban land conversion is an inevitable phenomenon in urbanization arid industrialization. And the decision-making issue about this conversion is multi-objective because the social decision maker (the whole of central government and local authority) has to integrate the requirements of different interest groups (rural collective economic organizations, peasants, urban land users and the ones affected indirectly) and harmonize the sub-objects (economic, social and ecological outcomes) of this land allocation process. This paper established a multi-objective programming model for rural-urban land conversion decision-making and made some social welfare analysis correspondingly. Result shows that the general object of rural-urban land conversion decision-making is to reach the optimal level of social welfare in a certain state of resources allocation, while the preference of social decision makers and the value judgment of interest groups are two crucial factors which determine the realization of the rural-urban land conversion decision-making objects.
In this present article we have given some multiobjective programming problems with their symmetric duals and have derived weak and strong duality results with respect to such programs. Moreover, we have also used mos...
详细信息
In this present article we have given some multiobjective programming problems with their symmetric duals and have derived weak and strong duality results with respect to such programs. Moreover, we have also used most general type of invexity assumptions involved with the functions which are related to the programming problems. It is to be pointed out that the objective functions in such programs contain terms like support functions which in turn are able to give results on particular classes of programs involving quadratic terms. Our results in particular give as special cases some earlier results on symmetric duals given in the current literature. (c) 2004 Published by Elsevier B.V.
A weight assessing method is given for solving a multiple attribute decision problem involving one decision maker. The method provides significant freedom to the decision maker who is asked only to specify certain gro...
详细信息
A weight assessing method is given for solving a multiple attribute decision problem involving one decision maker. The method provides significant freedom to the decision maker who is asked only to specify certain groups of attributes and the corresponding joint weights. The method then provides a sophisticated interaction between various levels of the attributes involved. Furthermore, if the decision maker wishes to give additional information of the above-mentioned kind, he establishes an interaction on the level of the solution process. This can compensate for the inherent limitations of any method based on scalar utility functions by allowing a certain intransitivity and incomparability of preferences, which are natural in multiple attribute situations. [ABSTRACT FROM AUTHOR]
In this paper we develop a multicriteria credibilistic framework for portfolio rebalancing. We use an expected value model with fuzzy parameters considering return, risk and liquidity as key financial criteria. The tr...
详细信息
In this paper we develop a multicriteria credibilistic framework for portfolio rebalancing. We use an expected value model with fuzzy parameters considering return, risk and liquidity as key financial criteria. The transaction costs are assumed to be paid on the basis of incremental discounts and are adjusted in the net return of the portfolio. A solution procedure based on fuzzy goal programming and a hybrid intelligent algorithm that combines fuzzy simulation with a real-coded genetic algorithm is presented to solve the portfolio rebalancing problem. The approach adopted here has the advantage of handling the multicriteria portfolio rebalancing problem where the fuzzy parameters are characterized by general functional forms. An empirical study is included to demonstrate the effectiveness of the solution approach and efficiency of the model in practical applications of rebalancing an existing portfolio. (c) 2012 Elsevier B.V. All rights reserved.
This study addresses a fundamental difficulty in designing cellular manufacturing (CM) systems, the cell formation problem. This problem has its strategic importance in that it affects the fundamental structure and ov...
详细信息
This study addresses a fundamental difficulty in designing cellular manufacturing (CM) systems, the cell formation problem. This problem has its strategic importance in that it affects the fundamental structure and overall layout of a CM system. A heuristic model is developed which assigns parts and machines to manufacturing cells while taking into account machine capacities, product routings, relevant costs, and several objectives of production systems. A full factorial experimental design is used to evaluate the effects of environmental factors on the performance of the heuristic model. Large cell formation problems are solved with the heuristic model to further characterize the model with respect to solution characteristics and computer run time.
In this paper, we propose a method for the solution of a multiobjective optimal control problem (MOOCP) in a linear distributed-parameter system governed by a wave equation. An explicit solution for the wave equation ...
详细信息
In this paper, we propose a method for the solution of a multiobjective optimal control problem (MOOCP) in a linear distributed-parameter system governed by a wave equation. An explicit solution for the wave equation is derived and the control problem of this distributedparameter system is reduced to an approximate multiobjective programming problem. The fuzzy goals are incorporated for objectives and the equilibrium problem in terms of maximization of the degree of attainment for the aggregated fuzzy goals is considered. The solution of the equilibrium optimization problem is a Pareto optimal solution with the best satisfaction performance which is achieved by using a metaheuristic algorithm such as the simulated annealing (SA) together with the simplex method of linear programming (LP) problems. An illustrative numerical example is presented to indicate the efficiency of the proposed method and the capability of the SA in finding optimal solution compared with two popular metaheurestics. (C) 2014 Production and hosting by Elsevier B. V. on behalf of Ain Shams University.
Purchases from vendors involve significant costs for many firms. Decisions related to these purchases include the selection of vendors and the determination of order quantities to be placed with the selected vendors. ...
详细信息
Purchases from vendors involve significant costs for many firms. Decisions related to these purchases include the selection of vendors and the determination of order quantities to be placed with the selected vendors. Such decisions are frequently multiobjective in nature. That is, they are evaluated by more than one criterion. At least 23 criteria for various vendor selection problems have been identified. In this article, we present a multiobjective approach to systematically analyze the inherent tradeoffs involved in multicriteria vendor selection problems. The approach is motivated by, and demonstrated with, an actual purchasing problem facing a division of a Fortune 500 company.
暂无评论