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1.
Shark-diving tourism provides important economic benefits to the Maldives. We examine the link between shark conservation actions and economic returns from diving tourism. A combined travel cost and contingent behaviour approach is used to estimate the dive trip demand under different management scenarios. Our results show that increasing shark populations could increase dive-trip demand by 15%, raising dive tourists’ welfare by US$58 million annually. This could result in annual economic benefits for the dive-tourism industry of >US$6 million. Conversely, in scenarios where shark populations decline, where dive tourists observe illegal fishing, or if dive operators lack engagement in shark conservation, dive trip demand could decrease by up to 56%. This decline causes economic losses of more than US$24 million annually to the dive tourism industry. These results highlight the dependence of the shark-diving industry on the creation and enforcement of appropriate management regimes for shark conservation.  相似文献   
2.
Motor carrier safety is an important concern of shippers, carriers, policy makers, consignees, insurance providers, and the motoring public. One aspect of carrier safety that has garnered substantial attention is whether carriers making greater use of owner–operators are more or less safe vis‐à‐vis carriers making greater use of employee drivers. Currently, conflicting theoretical predictions exist regarding the direction of this relationship. In this article, we offer a reconciliation of the alternative theoretical predictions by developing a coherent theory that merges sociological rational choice theory and theory regarding motor carrier safety. We subject our theory to empirical testing by fitting a series of seemingly unrelated regression models to a vector of safety measures tracked as part of the Federal Motor Carrier Safety Administration's Compliance, Safety, and Accountability program. Our results are consistent with our proposed theory of owner—operator safety and provide meaningful theoretical and managerial implications and directions for future research.  相似文献   
3.
ABSTRACT

A compact cat swarm optimization scheme (cCSO) is proposed in this paper, which is designed to solve application domains plagued with limited memory and less-computation power, as a member of cat swarm optimization algorithms (CSO), it composes of two sub-modes, i.e., tracing and seeking modes, so it keeps the same search logic of CSO. On the other hand, cCSO inherits the main feature of compact algorithms, a normal probabilistic model is used to represent the population of solutions instead of processing an actual population, which ensures the cCSO to have the modest memory requirement. The updating vector for the probabilistic model provides a clear moving direction for cats in next step. A cat without historical position and velocity is applied in the algorithm. When the cat is in seeking mode, it employs a differential operator to update the cat’s position, which makes it possible for the cat to have multiple searching directions. Experimental results show that cCSO has pretty performance compared with respect to some population-based testing benchmarks. And it also shows superior performance in convergence rate to some compact optimization algorithms. The case study of gray image segmentation proves that it suits for solving the optimization problem by limited hardware.  相似文献   
4.
Data envelopment analysis (DEA) has recently become relatively popular with road safety experts. Therefore, various decision-making units (DMUs), such as EU countries, have been assessed in terms of road safety performance (RSP). However, the DEA has been criticized because it evaluates DMUs based only on the concept of self-assessment, and, therefore does not provide a unique ranking for DMUs. Therefore, cross efficiency method (CEM) was developed to overcome this shortcoming. Peer-evaluations in addition to self-evaluation have made the CEM to be recognized as an effective method for ranking DMUs. The traditional CEM is based only on the standard CCR (Charnes, Cooper and Rhodes) model, and it evaluates DMUs according to their position relative to the best practice frontier while neglecting the worst practice frontier. However, the DMUs can also be assessed based on their position relative to the worst practice frontier. In this regard, the present study aims to provide a double-frontier CEM for assessing RSP by taking into account the best and worst frontiers simultaneously. For this purpose, the cross efficiency and cross anti-efficiency matrices are generated.Even though a weighted average method (WAM) is most frequently used for cross efficiency aggregation, the decision maker's (DM) preference structure may not be reflected. For this reason, the present study mainly focuses on the evidential reasoning approach (ERA), as a nonlinear aggregation method, rather than the linear WAM. Equal weights are often used for cross efficiency aggregation; consequently, the effect of the DM's subjective judgments in obtaining the overall efficiency is ignored. In this respect, the minimax entropy approach (MEA) and the maximum disparity approach (MMDA) are applied for determining the ordered weighted averaging (OWA) operator weights for cross efficiency aggregation. The weighted cross efficiencies and cross anti-efficiencies are then aggregated using the ERA. Finally, the proposed method, called DF-CEM-ERA, is used to evaluate the RSP of EU countries as well as Serbian police departments (PDs).  相似文献   
5.
This study investigates the advantages and the potentiality of the ‘tourist kit’, an Italian solution based on the concept of a prepaid card that is issued by a large postal operator. The destination card can be reloaded by tourists according to their needs and its validity is not restricted to short periods. Thus, the kit provides tourists with an integrated, practical, and flexible tool capable of making their stay more enjoyable as it allows cardholders to choose and buy many products and services at discounted prices. The kit creates customer loyalty by utilising smart technology aimed at collecting accurate tourist information. This model deserves attention because it is probably the world's first case of a large postal operator entering the tourism sector with the proposal of an integrated and advanced destination card scheme. This research also discusses interesting opportunities and challenges related to the implementation of new generation tourist cards.  相似文献   
6.
Future 5G networks aim at providing new high-quality wireless services to meet stringent and case-specific needs of various vertical sectors beyond traditional mobile broadband offerings. 5G is expected to disrupt the mobile communication business ecosystem and open the market to drastically new sharing based network operational models. 5G technical features of network slicing and small cell deployments in higher carrier frequencies will lower the investment barrier for new entrants to deploy local radio access networks and offer vertical specific services in specific areas and allow them lease the remaining required infrastructure on demand from mobile network operators (MNO) or infrastructure vendors. To realize the full vision of 5G to benefit the society and promote competition, innovation and emergence of new services when the 5G end-to-end network spans across different stakeholders administrative domains, the existing regulations governing the mobile communication business ecosystem are being refined. This paper provides a tutorial overview on how 5G innovations impact mobile communications and reviews the regulatory elements relevant to 5G development for locally deployed networks. This paper expands the recent micro licensing model for local spectrum authorization in future 5G systems and provides guidelines for the development of the key micro licensing elements. This local micro licensing model can open the mobile market by allowing different stakeholders to deploy local small cell networks with locally issued spectrum licenses ensuring pre-defined quality guarantees for the vertical sectors’ case specific needs.  相似文献   
7.
赫兵 《价值工程》2014,(30):19-21
本文从企业控制环境、风险评估、控制活动以及信息沟通四个方面针对广东省高速公路交通企业开展实地问卷调研。并对调研结果进行统计分析。调研结果显示:目前在交通企业目前内部控制体系中普遍存在组织架构不健全、资金、债务管理不善等问题。立足于调研结果,通过分析交通企业风险产生的环节,总结得出交通企业风险产生机制。结果表明,交通企业风险产生环节主要是1工程准备和施工环节;2融资信贷环节;3市场开拓、项目合作与并购环节。而这些环节之所会引发风险的产生最根本的原因是企业内部控制失调。鉴于此,本研究结合交通企业自身的特点,运用全面风险管理论,提出改善企业内部控制,并与风险管理相结合的方法。  相似文献   
8.
This paper studies the income fluctuation problem without imposing bounds on utility, assets, income or consumption. We prove that the Coleman operator is a contraction mapping over the natural class of candidate consumption policies when endowed with a metric that evaluates consumption differences in terms of marginal utility. We show that this metric is complete, and that the fixed point of the operator coincides with the unique optimal policy. As a consequence, even in this unbounded setting, policy function iteration always converges to the optimal policy at a geometric rate.  相似文献   
9.
经营者持股效应的理论分析   总被引:2,自引:0,他引:2  
现代企业制度产生“两权分离”,形成委托——代理关系,产生代理问题,而经营者持股是解决代理问题的一种激励方案。本文认为,经营者持股可以满足代理人的多种需要,从而激励代理人产生有利于实现企业目标的行为;经营者持股是代理人参与企业剩余分配的有效方式,是建立激励契约的必然选择。  相似文献   
10.
侯婕 《价值工程》2015,(3):211-212
作者精要总结自身对CAD软件的研究,同时联系参与CAD室内设计的经历,分析利用CAD软件为建筑室内进行设计的主要操作技术与相关技巧,深化设计师们对CAD软件的认识。  相似文献   
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