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71.
This paper presents a bi-level robust optimization model, where a food company maximizes its profit and minimizes post-harvest loss by optimally deploying grain processing/storage facilities and determining grain purchase price, while a group of spatially distributed non-cooperative farmers determine harvest time, shipment, storage, and market decisions under yield uncertainty and market equilibrium. The non-cooperative behavior of the food company and the farmers is represented by a bi-level Stackelberg leader follower’s game model with mixed-integer decision variables. The proposed model and solution approach are applied to case studies for Illinois and Brazil. 相似文献
72.
This paper aims to measure the perceived container leasing prices at different ports by presenting a two-stage optimization method. In stage I, we propose a practical liner shipping network design problem with empty container repositioning. The proposed problem further considers the use of foldable containers and allows the mutual substitution between empty containers to decrease the number of empty containers to be repositioned. In stage II, the inverse optimization technique is used to determine the perceived container leasing prices at different ports, based on the solution obtained in stage I. Based on a set of candidate liner shipping service routes, a mixed-integer nonlinear programming model is built for the proposed problem in stage I. The nonlinear terms are linearized by introducing the auxiliary variables. Numerical experiments based on a realistic Asia-Europe-Oceania liner shipping network are carried out to account for the effectiveness of our two-stage optimization method. 相似文献
73.
Growing importance of intermodal transportation necessitates modeling and solving load planning problems by taking into account various complex decisions simultaneously like transportation mode/service type selection, load allocation, and outsourcing. This paper presents a mixed-integer mathematical programming model for a multi-objective, multi-mode and multi-period sustainable load planning problem by considering import/export load flows to satisfy transport demands of customers and many other related issues. Several multiple objective optimization procedures are utilized in order to handle conflicting objectives simultaneously under crisp and fuzzy decision making environments. A real-life case study is also performed to present application and usefulness of the proposed model. 相似文献
74.
This paper considers the design of an immobile service system in which each facility’s service process is subject to the risk of interruptions. The location-capacity decisions and allocations are simultaneously made to maximize the difference between the service provider’s profit and the sum of customers’ transportation and waiting costs. An efficient Lagrangian-based solution algorithm is developed, which solves large-sized instances with up to 50 service facilities and 500 customers in a few seconds. Several sensitivity analyses and managerial insights are presented. The model is also applied to a case study on a logistics network design problem in the zinc mining industry. 相似文献
75.
76.
Air transport demand forecasting is receiving increasing attention, especially because of intrinsic difficulties and practical applications. Total passengers are used as a proxy for air transport demand. However, the air passenger time series usually has a complex behavior due to their irregularity, high volatility and seasonality. This paper proposes a new hybrid approach, combining singular spectrum analysis (SSA), adaptive-network-based fuzzy inference system (ANFIS) and improved particle swarm optimization (IPSO), for short-term air passenger traffic prediction. The SSA is used for identifying and extracting the trend and seasonality of air transport demand and the artificial intelligence technologies, including ANFIS and IPSO, are utilized to deal with the irregularity and volatility of the demand. The HK air passenger data are collected to establish and validate the forecasting model. Empirical results clearly points to the enormous potential that the proposed approach possesses in air transport demand forecasting and can be considered as a viable alternative. 相似文献
77.
经济增速维持高位、就业形势趋好、收入分配格局改善等利好因素支撑着我国居民消费的长期增长趋势。但是,消费率偏低仍然是困扰我国经济发展方式转变的主要困难。收入分配差距大、公共服务不健全、消费环境不佳、通货膨胀、外部不确定性等矛盾同时制约着消费增长。必须长期制度创新与短期政策优化相结合,力促居民消费增长。 相似文献
78.
79.
随着我国加入WTO及世界经济一体化 ,我国在医药流通领域的管制将于 2 0 0 5年放开。以我国医药零售业的代表企业———深圳一致药业股份有限公司、上海华氏大药房有限公司为例同世界巨头———CVS和Walgreen在企业的发展历史、赢利模式、绩效评价指标分析等方面做横向比较 ,找出我国医药零售企业和世界巨头的差距 ,在此基础上才能从产业组织结构优化的角度制定出相应的措施 相似文献
80.
This paper analyzes long-term comovements between hedge fund strategies and traditional asset classes using multivariate cointegration
methodology. Since cointegrated assets are tied together over the long run, a portfolio consisting of these assets will have
lower long-term volatility. Thus, if the presence of cointegration lowers uncertainty, risk-averse investors should prefer
assets that are cointegrated. Long-term (passive) investors can benefit from the knowledge of cointegrating relationships,
while the built-in error correction mechanism allows active asset managers to anticipate short-run price movements. The empirical
results indicate there is a long-run relationship between specific hedge fund strategies and traditional financial assets.
Thus, the benefits of different hedge fund strategies are much less than suggested by correlation analysis and portfolio optimization.
However, certain strategies combined with specific stock market segments offer portfolio managers adequate diversification
potential, especially in the framework of tactical asset allocation.
相似文献
Dieter G. KaiserEmail: |