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31.
In this paper we propose a 4-index formulation for the uncapacitated multiple allocation hub location problem tailored for urban transport and liner shipping network design. This formulation is very tight and most of the tractable instances for MIP solvers are optimally solvable at the root node. While the existing state-of-the-art MIP solvers fail to solve even small size instances of problem, our accelerated and efficient primal (Benders) decomposition solves larger ones. In addition, a very efficient greedy heuristic, proven to be capable of obtaining high quality solutions, is proposed. We also introduce fixed cost values for Australian Post (AP) dataset.  相似文献   
32.
This study contributes to research on the impact that consumer buzz has on movie distribution and box office success by examining the impact of buzz generated about the individual stars and about the movie itself. The results indicate that movie buzz is instrumental in boosting box office revenue throughout the theatrical release, not just in the later run, as has been suggested in previous studies. Star buzz can enhance box office receipts during the opening week and can contribute to the public's anticipation of the movie pre-release. However, early buzz can have a negative impact on revenue during subsequent weeks if the movie fails to resonate with the audiences. Model simulations reveal that, even for poorly received films, the overall impact of star buzz is positive because the initial revenue boost normally outweighs the later decline. Thus, this study empirically demonstrates the positive impact of star buzz on revenue, which helps shed light on the long-standing debate regarding the importance of star participation in the success of a movie.  相似文献   
33.
针对百度文库侵权案例的辨析,本文对百度搜索引擎ISP在实质性非侵权用途、共同侵权、避风港原则等方面进行认定。从而提出对我国在网络侵权方面应加强完善间接侵权规则、界定网络服务主体的性质、适当加大网络服务提供商的责任以及制定《网络侵权责任法》的规制建议。通过本文的研究,寻求搜索引擎行为在法律规制过程中所追求的价值目标。  相似文献   
34.
针对双站定位涉及的跳频信号多普勒频差估计问题,提出了归一化的频差最大似然估计算法,利用两个定位站接收到的跳频脉冲串信号,构建一个关于基准跳频频率多普勒频差的似然函数,通过网格搜索得到使似然函数最大的多普勒频差估计,既解决了跳频信号在不同跳频频率上多普勒频差不一致的问题,又充分利用在不同频率的脉冲串信号提高了多普勒频差估计精度。通过仿真对算法的性能进行了评估,结果表明,与基于子空间的算法比较,在脉冲数达到240个时,所提算法执行效率提升30%以上。  相似文献   
35.
刘丙泉  潘鹏杰 《价值工程》2010,29(17):158-159
随着我国电子商务发展的不断深入,这种新型的商业模式提高了对互联网情报信息搜索量和质的要求;元搜索引擎技术的不断进步使信息检索量有了很大的提高,但检索响应时间和检索准确度成为制约该技术在电子商务领域应用的瓶颈;本文通过基于传统的k-means聚类算法,优化了其类别选择机制获得了信息检索的高准确度和快速响应;实证结果表明,优化的k-means聚类算法具有较高的聚类质量和算法弹性,是元搜索引擎技术的有利补充。  相似文献   
36.
人民银行国库部门的资金风险主要是内控体系不健全,内控制度执行不到位。构建国库部门内控体系的基本原则,建立科学高效的国库业务流程,制定重点环节风险防范机制,针对风险点落实具体风险防范措施,是人民银行国库资金风险点查找与防范的有效方法。  相似文献   
37.
Many fundraising charities invest heavily in content marketing, often using consultants to direct their content-marketing efforts. Thus it is vital to establish whether certain key aims of content marketing suggested by literature in the field actually match the aspects of content marketing deemed most important by charity donors. This paper examines the significance attached by samples of charities, donors, and content-marketing consultancies to four possible major objectives of content marketing—the attainment of high–search-engine-results-page rankings, image enhancement through impression management, the stimulation of public perceptions of organizational transparency, and the creation of messages that “go viral.” Several major differences in perceptions emerged among the three groups, with substantial implications for how fundraising charities should manage their content-marketing programs and activities. Charity managements need to consider carefully and critically the possible returns on large-scale expenditures intended to pursue the putative aims of content marketing that are routinely advocated by practitioner and academic literature.  相似文献   
38.
The implications of current trends in nanotechnology for the agri-food sector in India are assessed. Using published literature and patents data, a model to organize the information is developed through a specially designed database. The database allows mapping research themes in nanotechnology to specific sectors in the agricultural value chain to enable a rational assessment of the potential applications of nanotechnology in the agri-food sector, identifying and prioritizing research needs across the agricultural value chain, and assessing the environmental and societal implications of this emerging technology.  相似文献   
39.
In this paper, we consider a flowshop scheduling problem with sequence-dependent setup times and a bicriteria objective to minimize the work-in-process inventory for the producer and to maximize the customers' service level. The use of a bicriteria objective is motivated by the fact that successful companies in today's environment not only try to minimize their own cost but also try to fulfill their customers' need. Two main approaches, permutation and non-permutation schedules, are considered in finding the optimal schedule for a flowshop. In permutation schedules the sequence of jobs remains the same on all machines whereas in non-permutation schedule, jobs can have different sequence on different machines. A linear mathematical model for solving the non-permutation flowshop is developed to comply with all of the operational constraints commonly encountered in the industry, including dynamic machine availabilities, dynamic job releases, and the possibility of jobs skipping one or more machines, should their operational requirements deem that it was necessary. As the model is shown to be NP-hard, a metasearch heuristic, employing a newly developed concept known as the Tabu search with embedded progressive perturbation (TSEPP) is developed to solve, in particular, industry-size problems efficiently. The effectiveness and efficiency of the search algorithm are assessed by comparing the search algorithmic solutions with that of the optimal solutions obtained from CPLEX in solvable small problem instances.  相似文献   
40.
We study the business‐cycle behavior of segmented labor markets with flexibility at the margin (e.g., just affecting fixed‐term contracts). We present a matching model with temporary and permanent jobs (i) where there is a gap in the firing costs associated with these types of jobs and (ii) where there are restrictions in the creation and duration of fixed‐term contracts. We show that a labor market with ``flexibility at the margin'' increases the unemployment volatility with respect to one that is fully regulated. This analysis yields new insights into the interpretation of the recent volatility changes witnessed in the OECD area.  相似文献   
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