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41.
This paper addresses a novel sustainable hub location problem (SHLP) in which two new environmental-based cost functions accounting for air and noise pollution of vehicles are incorporated. To cope with uncertain data incorporated in the model, a mixed possibilistic–stochastic programming approach is proposed to construct the crisp counterpart. A simulated annealing (SA) and an imperialist competitive algorithm (ICA) with a new solution representation are developed to solve real-sized instances whose performances are compared with a proposed lower bound. Finally, some computational experiments are provided to demonstrate the effectiveness of the proposed model and solution approaches.  相似文献   
42.
Biofuels are emerging as a prominent renewable and sustainable energy sources in developed countries. In this sense, this paper presents a case study in which a biorefinery has to be sited in Northern Spain. Thus, the strategic decision of locating such a facility is deeply investigated through strategic policy evaluation. Then, tactical decisions ranging from purchasing and transportation policies to storage protocols are carried out. Only local and limited biomass can be harvested for supplying the biorefinery through a heterogeneous vehicle fleet. Moreover two different and mutually exclusive storage strategies are evaluated: direct supply from crops to biorefinery and using intermediate-collectors. Additionally, crop exploitation factors and biorefinery sizes are used to generate several scenarios in which the strategic decision of location as well as all the tactic decisions are made. Some mixed integer linear programming models are proposed to figure out all relevant decision problems.The results suggest that the Northwest study area as the best option to locate the biorefinery and recommend the intermediate-collector storage strategy. Moreover, the key information about critical biomass, crops and times are also provided.  相似文献   
43.
城镇化目前已经成为扩大改革开放的一项重要举措,但随着而来的就是相关基础服务设施不完善,严重影响了新城镇广大居民的生活质量和水平。因此,对于新建城镇相关物流服务设施的选址问题就变得尤为重要,交叉中值模型则是一个城镇区域内单一设施连续点选址的非常适合的方法。  相似文献   
44.
High-speed rail has developed both nationally and internationally in Europe as a successful alternative to both air and road over distances of 400–600 km. Inter-city traffic, especially between the major metropolitan areas in North-west Europe has benefitted greatly from the investment in this network. This paper explores two issues: the impact on the intermediate areas between these major metropolitan areas and the creation of potential cross-border inter-regional services. The evidence shows how both levels of service and potential economic impacts have been much less pronounced in these intermediate areas. Such areas have been affected both by a failure to see greatly improved direct access to major cities other than within their own countries and a lack of new cross-border inter-regional services. The paper argues that the creation of the high-speed rail TEN-T has not met the primary objectives of reducing regional disparities in accessibility or reducing the effect of national borders on regional integration. To achieve this requires not just infrastructure provision but an appropriate regulatory framework for service provision and accompanying measures at the local level.  相似文献   
45.
We propose a network flow model for dynamic selection of temporary distribution facilities and allocation of resources for emergency response planning. The model analyzes the transfer of excess resources between temporary facilities operating in different time periods in order to reduce deprivation. Numerical analysis shows that the location of temporary facilities is determined by the demand and supply points. This work contributes to the emergency response planning that requires a quick response for the supply of relief materials immediately after a disaster hits a particular area.  相似文献   
46.
This paper aims to review past literature on hotel location models and evaluate the state of the art, as well as set out future directions. This study divides hotel location models into three major categories: theoretical models, empirical models, and operational models. Four theoretical hotel location models are reviewed and discussed, including the tourist-historic city model, the mono-centric model, the agglomeration model, and the multi-dimensional model. Based on previous literature, six empirical models and three operational models of hotel location are elaborated. Furthermore, some challenges related to hotel location studies are discussed, and future research directions are provided. In particular, we advocate the development of more sophisticated hotel location models and the use of Geographic Information System (GIS) in hotel location analysis.  相似文献   
47.
The emergence of Brazil, Russia, India and China (BRIC) as international locations for foreign direct investment in R&D is a sign that multinationals are relocating their technological activities to new territories. This trend may weaken the supremacy of the developed countries until now considered leaders in innovation, and may mean the loss of the competitive advantages enjoyed by the countries considered intermediate innovators. This paper examines the situation of Spain as a typical intermediate economy and compares it to its main competitors among the BRICs. Based on eight case studies of subsidiaries with R&D centres in Spain, we conclude that the policies adopted by certain emerging economies to develop their national innovation systems are proving effective and that these countries now pose a threat to intermediate economies. However, the BRICs still lag behind in terms of the security of their institutional framework; this situation leaves intermediate countries in an advantageous position.  相似文献   
48.
This paper provides a systematic framework to determine local delivery centre (LDC) locations and service areas to reduce delivery costs and balance the allocation of parcel delivery loads to promote sustainable LDC development. Based on a case study of a parcel distribution company in Korea, this study proposes two strategies for LDC service area delineation within each terminal service boundary that either minimises the total delivery time or balances the allocation of delivery loads. This research contributes to improving cost efficiency and balancing delivery load allocations in planning LDC locations and service areas that can potentially promote the long-term mutual sustainable development of parcel distribution companies and their local delivery counterparts.  相似文献   
49.
This paper proposes a new strategic planning model for high-speed rail ventures. It is a mixed-integer optimization model that applies to a given line and focuses on two key strategic decisions: station location and fleet composition. Our purpose is to improve on previous station location models by including fleet composition decisions. In the new model, we additionally take into account in an approximate fashion the interrelationships between strategic and subsequent tactical decisions, regarding line planning, train scheduling and fleet assignment issues. The usefulness of the model is demonstrated for a case study involving a planned Lisbon-Oporto high-speed rail line.  相似文献   
50.
The problem of sequentially estimating a location parameter and powers of a scale parameter is considered in the case when the observations become available at random times. Certain classes of sequential estimation procedures are derived under an invariant balanced loss function and with the observation cost determined by a convex function of the stopping time and the number of observations up to that time.  相似文献   
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