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排序方式: 共有136条查询结果,搜索用时 365 毫秒
31.
This research aims at finding the best governing policy for offshore outsourcing of business activities. We use Analytical Network Process, a multicriteria decision making methodology, to create the evaluation framework. From the perspective of decision makers, stakeholders, and influence groups, four policy options are evaluated with respect to approximately 50 economic, political, technological and other factors. The model provides both long-term and short-term views of the outsourcing issue concerned to all parties. The all-inclusive approach helps policy makers to decide on the best policy and has the potential to ease tension between proponents and opponents of offshore outsourcing. 相似文献
32.
Kenneth E. Boulding 《Annals of Operations Research》1984,2(1):11-21
Humans are constantly making evaluations about the direction of movement in time of systems perceived as relevant, in terms of whether things are moving to the better or to the worse. The relevant system may be very small or as large as the whole planet earth; evaluations seldom go beyond the solar system. We evaluate things like health, wealth, security, justice, etc. and we have a strange capacity for putting many diverse variables together into a single rough evaluation. Accountants evaluate the state of a balance sheet or position statement quantitatively in terms of dollars; economists evaluate aggregates like the GNP. But almost everyone goes beyond quantification into rough, qualitative evaluations of the total state of a system. The evaluation of overall systems runs into the difficulty that different persons evaluate the same perceived change differently. Nevertheless, there are many processes in society by which differing evaluations are coordinated, even if they are not reconciled. The market is one, politics is another, and the moral order is a third. In large systems we are unlikely to come out with a single answer to even the question of whether things are getting better or worse. But we can identify certain instances where there is wide agreement that a movement is for the worse: the cliffs-disasters, premature deaths, losses of liberty, etc. We can furthermore specify certain dynamic systems likely to produce these dramatic worsenings, and perhaps do something about them. 相似文献
33.
本文提出优化视角下专家权重信息未知的区间直觉模糊三支群决策方法。首先利用区间直觉模糊加权平均算子集结不同专家提供的区间直觉模糊损失评价,获得群体综合损失评价结果。以专家个体与群体综合评价相似度越髙,越能反映群体综合评价意见且赋予髙的专家权重为原则,分别构建专家权重信息完全未知和部分已知的权重确定模型。进而建立确定区间直觉模糊三支决策概率阈值对的优化模型,并提出基于专家权重信息未知的区间直觉模糊三支群决策方法。最后,算例分析及比较结果表明所提出方法的有效性。 相似文献
34.
We examine voting location problems in which the goal is to place, based on an election amongst the users, a given number of facilities in a graph. The user preference is modeled by shortest path distances in the graph. A Condorcet solution is a set of facilities to which there does not exist an alternative set preferred by a majority of the users. Recent works generalize the model to additive indifference and replaced user majority by γ-proportion. 相似文献
35.
Hideyuki Nojiri 《Fuzzy Sets and Systems》1980,3(2):137-150
This paper formulates a fuzzy team decision problem in a changing environment. The concept of a fuzzy set is introduced to formulate the team decision processes in a dynamic environment which contains fuzzy states, fuzzy information functions, fuzzy information signals, fuzzy decision functions and fuzzy actions. 相似文献
36.
Andres Weintraub Richard L. Church Alan T. Murray Monique Guignard 《Annals of Operations Research》2000,96(1-4):271-285
Linear Programming and Mixed Integer Linear Programs have been used for forest planning since the 60's to support decision
making on forest harvesting and management. In particular, during the last two decades of forest management there has been
an increased interest in spatial issues. Further, new environmental concerns, such as resource sustainability and wildlife
protection, impose that increased attention be paid to activities carried out on the ground. Road building needed for access
also requires spatial definiton. As a result, more complex models must be used. We discuss the issues which have led to the
combinatorial nature of some main forest management problems and the solution algorithms that have been proposed for these
problems, including local search heuristics, random search approaches, strengthening of mixed integer model formulations and
Lagrangian relaxation. In this survey, we discuss which of the proposed approaches have been used succesfully, the advantages
and shortcomings of each and what are still open research problems.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
37.
Hopf Bifurcation Analysis for a Delayed Business Cycle Model-The Equivalence of Multiple Time Scales Versus Center Manifold Reduction Methods 下载免费PDF全文
In this paper, we study the Hopf bifurcation of a model with a second order term, which is the business cycle model with delay. Multiple time scales method, which is mainly used by the engineering researchers, and center manifold reduction method, which is mainly used by researchers from mathematical society, are used to derive the two types of normal forms near the Hopf critical point. A comparison between the two methods shows that the two normal forms are equivalent. Scholars can derive the normal form by choosing appropriate methods according to their actual demands. Moreover, bifurcation analysis and numerical simulations are given to verify the analytical predictions. 相似文献
38.
Hamed Jalali Raïsa Carmen Inneke Van Nieuwenhuyse Robert Boute 《European Journal of Operational Research》2019,272(1):195-206
In this article, we consider the impact of finite production capacity on the optimal quality and pricing decisions of a make-to-stock manufacturer. Products are differentiated along a quality index; depending on the price and quality levels of the products offered, customers decide to either buy a given product, or not to buy at all. We show that, assuming fixed exogenous lead times and normally distributed product demands, the optimal solution has a simple structure (this is referred to as the load-independent system). Using numerical experiments, we show that with limited production capacity (which implies load-dependent lead times) the manufacturer may have an incentive to limit the quality offered to customers, and to decrease market coverage, especially in settings where higher product quality leads to higher congestion in production. Our findings reveal that the simple solution assuming load-independent lead times is suboptimal, resulting in a profit loss; yet, this profit loss can be mitigated by constraining the system utilization when deciding on quality and price levels. Our results highlight the importance of the relationship between marketing decisions and load-dependent production lead times. 相似文献
39.
40.
H. Kagiwada R. Kalaba K. Spingarn 《Journal of Optimization Theory and Applications》1980,30(4):589-600
A new generation of C3 (command, control, and communication) models for military cybernetics has been developed in recent papers. Recursive equations for the solution of the C3-problem have been derived for an amphibious campaign with linear time-varying dynamics. Air and ground commanders are assumed to have different modes of intelligence and communications. Numerical results are summarized, and the relative importance of intelligence and communications is discussed. 相似文献