The Open Operational Research Journal最新文献

{"title":"An Efficient Solution Method for 0-1 Random Fuzzy Programming Problems Considering the Relaxation Problems","authors":"T. Hasuike, H. Ishii, H. Katagiri","doi":"10.2174/1874243200802010038","DOIUrl":"https://doi.org/10.2174/1874243200802010038","url":null,"abstract":"This paper considers a general 0-1 random fuzzy programming problem including some previous 0-1 stochastic and fuzzy programming problems. The proposal problem is not a well-defined problem due to including random fuzzy variables. Therefore, by introducing chance constraint and fuzzy goal for objective function and considering the maximi- zation for the degrees of possibility that the objective function value satisfies the fuzzy goal, main problem is transformed into a deterministic equivalent problem. Furthermore, by using the assumption that each random variable is distributed ac- cording to a normal distribution, the problem is equivalently transformed into a basic 0-1 programming problem, and the efficient strict solution method to find an optimal solution is constructed.","PeriodicalId":337071,"journal":{"name":"The Open Operational Research Journal","volume":"195 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122521958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Variational Inequalities for Modeling Auction Markets with Price Mappings","authors":"I. Konnov","doi":"10.2174/1874243200802010029","DOIUrl":"https://doi.org/10.2174/1874243200802010029","url":null,"abstract":"We propose several new models for separate and spatially distributed auction based markets where partici- pants' reactions are described by general price mappings and show that they admit equivalent variational inequality for- mulations. This approach is utilized for the derivation of existence and uniqueness results and for construction of efficient solution methods.","PeriodicalId":337071,"journal":{"name":"The Open Operational Research Journal","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124218060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the Efficiency of Feasible Solutions of a Multicriteria Assignment Problem","authors":"A. Bufardi","doi":"10.2174/1874243200802010025","DOIUrl":"https://doi.org/10.2174/1874243200802010025","url":null,"abstract":"The particular structure of the assignment problem made of it a very popular subject of study and an important research tool in operations research and management science. In addition to the importance that the assignment problem represents in its own, it can appear as a relaxation of more complex combinatorial optimization problems. That is why the assignment problem has received great attention from the operations research community. The assignment problem may appear as an optimization problem with multiple objectives. In this paper, we address the problem of efficiency of feasible solutions of a multicriteria assignment problem. It is done in two steps. In the first step, we determine whether or not a given feasible solution of a multicriteria assignment problem is efficient. In a second step, if the feasible solution is not ef- ficient, we provide an efficient solution that dominates it. The proposed method consists of transforming the original prob- lem into an assignment problem with side constraints for which solution techniques already exist.","PeriodicalId":337071,"journal":{"name":"The Open Operational Research Journal","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126017218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Minimizing Makespan on Parallel Machines with Machine Eligibility Restrictions","authors":"Chien-Hung Lin, C. Liao","doi":"10.2174/1874243200802010018","DOIUrl":"https://doi.org/10.2174/1874243200802010018","url":null,"abstract":"In this paper, we consider a parallel machine problem where machines and jobs can be classified into two levels: high and low levels. A high-level machine can process all jobs while a low-level machine can process only low-level jobs. The objective of the problem is to minimize the makespan. This problem is a special case of the parallel machine problem with machine eligibility restrictions. The problem is NP-hard and a heuristic algorithm has recently been proposed. However, there are no algorithms in the literature that can solve the problem to optimality. In this paper, we develop such an exact algorithm by utilizing some useful properties inherent in the problem. Computational experiments show that the developed algorithm can find the optimal solution for various-sized problems in a short time.","PeriodicalId":337071,"journal":{"name":"The Open Operational Research Journal","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121619558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long Memory and Structural Breaks in the Spanish Stock Market Index","authors":"G. Caporale, L. Gil‐Alana","doi":"10.2174/1874243200802010013","DOIUrl":"https://doi.org/10.2174/1874243200802010013","url":null,"abstract":"It is well known that the Spanish stock market index (IBEX 35) exhibits unit roots. However, the implications of possible structural breaks in this series have not been deeply investigated. In this paper, we show that, when including a break at the beginning of 1998, the order of integration of the series becomes slightly smaller, strengthening the evidence of mean-reverting behaviour. When the break date is supposed to be unknown, it is found to be January 1998, with both subsamples still being characterised by a high degree of persistence.","PeriodicalId":337071,"journal":{"name":"The Open Operational Research Journal","volume":"212 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130525826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparing Fundamentals of Additive and Multiplicative Aggregation in Ratio Scale Multi-Criteria Decision Making","authors":"E. U. Choo, W. Wedley","doi":"10.2174/1874243200802010001","DOIUrl":"https://doi.org/10.2174/1874243200802010001","url":null,"abstract":"Additive and multiplicative aggregations of ratio scale preferences are frequently used in multi-criteria decision making models. In this paper, we compare the advantages and limitations of these two aggregation rules by exploring only their fundamental properties after ratio scaled local priorities and criteria weights have been successfully generated from the decision maker. The comparisons of these properties are therefore independent of ancillary procedures such as interac- tive elicitations from decision makers, pairwise comparisons and calculations of local priorities and criteria weights. We compare six fundamental properties of the two aggregation rules. The criteria weights used in the multiplicative aggrega- tion have complicated meanings which are not well understood and often mixed up in the ambiguous notion of \"criteria importance\". As the scaling factors of the local preference values do not appear explicitly in the computations of the rela- tive ratios of the overall preferences in the multiplicative aggregation model, the relative ratios remain unchanged when the scaling factors are changed or an alternative is added or deleted. Furthermore, the relative ratios in the multiplicative aggregation do not depend on similar local preference values which cancel each other out mathematically. It is quite evi- dent that the additive aggregation model is superior and easier for decision makers to use and understand. We recommend the additive aggregation rule over the multiplicative aggregation rule. Fundamental basic elements of the MCDM framework are first depicted without any specific interpretations im- posed on these elements. It is assumed that no relevant crite- rion is missed and each criterion is autonomous. In section 3, the measures of criteria weight, local and overall preferences are assumed to be in ratio scale. Some necessary conditions and the role of normalization are discussed. We then give a brief literature review, with particular attention to the differ- ent ancillary procedures and contradicting opinions in model interpretations. Additive and multiplicative aggregation rules are formally introduced in Section 5. In Section 6, we elabo- rate and compare the fundamental properties of these aggre- gation rules. Finally, we summarize and give some conclu- sions. 2. BASIC ELEMENTS OF MCDM MODEL The basic elements of a typical MCDM model include a set A={A1,A2,…,An} of n alternatives A1,A2,…,An and a set C={C1,C2,…,Cm} of m criteria C1,C2,…,Cm. The effect of the criteria C1,C2,…,Cm in C is represented by positive num- bers w1,w2,…,wm respectively. The vector w=(w1,w2,…,wm) is called the criteria weight vector of the criteria C1,C2,…,Cm in C. The criteria weight vector w is derived from question- ing the DM. The alternatives A1,A2,…,An can be evaluated under each individual criterion Cp, p=1,2,…,m. For each criterion Cp (p=1,2,…,m), the local preference of the alterna- tives A1,A2,…,An in A with respect to Cp is represented b","PeriodicalId":337071,"journal":{"name":"The Open Operational Research Journal","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116893904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Approximation Algorithm for the Capacitated Arc Routing Problem","authors":"Sanne Wøhlk","doi":"10.2174/1874243200802010008","DOIUrl":"https://doi.org/10.2174/1874243200802010008","url":null,"abstract":"In this paper we consider approximation of the Capacitated Arc Routing Problem, which is the problem of serv- icing a set of edges in a graph using a fleet of capacity constrained vehicles. We present a 7  3  2 W approximation algorithm for the problem and prove that this algorithm outperforms the only existing approximation algorithm for the problem. Fur- thermore, we give computational results showing that the new algorithm performs very well in practice. When solving an optimization problem to suboptimality, two goals are followed. The first goal is to obtain a solution that is as close to the optimal as possible, which leads to the construction of problem specific heuristics and meta heuris- tics, where the latter often outperforms the former. The sec- ond goal is to obtain a solution, which is guaranteed to be within a certain factor of the optimal. This goal leads to the construction of approximation algorithms. In this paper we will present an algorithm for the Capaci- tated Arc Routing Problem (CARP) with the triangle ine- quality preserved by the cost matrix, which is an approxima- tion algorithm with at most the same approximation factor as the only existing approximation algorithm for the problem, and which performs very well in practice, in that it is highly competitive to the existing problem-specific heuristics for the problem on the set of 143 benchmark instances. We refer to the algorithm as A-ALG.","PeriodicalId":337071,"journal":{"name":"The Open Operational Research Journal","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126987077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimal Population Size and Urban-Rural Composition of a Distant, Large, Arid Island: A Model and Some Numerical Simulations","authors":"Amnon Levy, R. Zamani","doi":"10.2174/1874243200701010009","DOIUrl":"https://doi.org/10.2174/1874243200701010009","url":null,"abstract":"Low population density and large distance from civilization centers generate high costs of isolation. Immigra- tion reduces these costs for veteran residents but reduces social and cultural cohesion, increases the demand for scarce re- sources and affects the rate of urban unemployment. An expected net benefit maximization model for determining the op- timal population size and the equilibrium urban-rural composition of an island similar to Australia is constructed. The model is simulated for various agricultural water prices. The simulation results illustrate the central role of the effect of immigration on urban unemployment rate in the determination of the island's optimal population size. INTRODUCTION This paper deals with the optimal population size and rural-urban composition of a distant, large, arid island. The island's current population is small and has a low fertility rate. Distance and dispersion hinder communication and provision of commodities and services and the island's in- habitants bear mental and material costs of isolation. Immi- gration is the main way for increasing the island's population density, strengthening the island's international integration and, thereby, moderating the costs of isolation borne by the island's inhabitants. However, immigration reduces the is- land's levels of cultural and social cohesion. It also affects the island's rural and urban land and water use and natural","PeriodicalId":337071,"journal":{"name":"The Open Operational Research Journal","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121108318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Impacts of Asian Currency Crisis on International Portfolio Diversification","authors":"Takkee Hui, R. Kurniawan, Hsuan-Yi Cheng","doi":"10.2174/1874243200701010001","DOIUrl":"https://doi.org/10.2174/1874243200701010001","url":null,"abstract":"This paper is to investigate the benefits of including bonds and stocks markets in the optimal portfolio using the classical model. Three types of investments: stocks alone, bonds alone, and a mix of stocks and bonds are considered. Ef- ficient frontier is constructed for each type of investment. This study is also to include international diversification choices before and after the recent Asian currency crisis. It has been shown that the risk of investment can be reduced by diversifi- cation across countries. For both before and after Asian currency crisis, our results show that investing in the bond mar- kets alone will provide substantial return and optimal risk reduction for investors who are risk averse. However, the com- bination of stocks and bonds will provide a better mix giving a highest return per unit risk. After the Asian currency crisis, the bond markets selected are shifted from North America markets to Oceania markets and France market. This analysis provides a comprehensive study for Singaporean investors but the research can be repeated from a different perspective such as Japan and US point of view.","PeriodicalId":337071,"journal":{"name":"The Open Operational Research Journal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130422763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Sensitivity Analysis of the International Investment Decision Model","authors":"Tsui-Yii Shih, C. Trappey","doi":"10.2174/1874243200802010060","DOIUrl":"https://doi.org/10.2174/1874243200802010060","url":null,"abstract":"Johanson and Vahlne's research provides a starting point for building a model that suits general international investments and decision making processes. This research derives an integer programming investment decision model that also considers investment costs and the risk attitudes of firms. The sensitivity analysis of the revised model demonstrates how risk attitudes and investment costs influence the optimal investment decision. Compared to the cost factors, the influ- ence of attitudes toward risk are the key to the overall decision making process.","PeriodicalId":337071,"journal":{"name":"The Open Operational Research Journal","volume":"227 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123246089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}