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141.
Recent empirical studies have evaluated if modifying electronic gambling machine (EGM) structural features could encourage safer gambling behaviors and decrease gambling-related problems. Several of these studies refer to Harm Reduction (HR), suggesting that the HR paradigm is useful to design, implement and test the efficacy of various prevention and treatment programs applied to EGM users. After reviewing the origins of HR and specifying its operational definition, this paper discusses the relevance of the HR framework for the study of measures related to EGM use and gambling in general. Examples are given to illustrate the arguments. The results show that HR has been over-inclusive in the field of gambling. A specific and operational definition and application of the HR framework is required for HR to be useful for the advancement of research in the gambling field. Disclosure: At the time of the study, Michael Cantinotti held a scholarship from the Loterie Romande (public-benefit lottery in Switzerland) for his doctoral studies. This study was funded by the Fonds pour la prévention et le traitement du jeu of the Fondation de l’Université Laval. During the study, the Centre québécois d’excellence pour la prévention et le traitement du jeu received financial support from the Ministère de la Santé et des Services Sociaux du Québec, the Fonds Québécois de la Recherche pour la Santé et la Culture, Loto-Québec, the Ontario Problem Gambling Research Center, and Harrah’s Operating Funds.  相似文献   
142.
Although there has been much speculation about the possible links between gambling and crime rates, relevant quantitative evidence has been practically non-existent in Australia to date. This paper reports the results of research that utilised a model designed to investigate the potential relationship between electronic gaming machine expenditures and property (income-generating) crime rates reported to police in local areas in South Australia in 2002–2003. The research found that the higher the expenditures on gaming machines in a particular local area per adult, the higher the income-generating crime rate in that area. No such relationship was found between gaming machine expenditure and non-income-generating crime rates. However, further research is required before any policy-relevant conclusions can be drawn.  相似文献   
143.
Quan-Ke Pan 《Omega》2012,40(2):166-180
Lot-streaming flow shops have important applications in different industries including textile, plastic, chemical, semiconductor and many others. This paper considers an n-job m-machine lot-streaming flow shop scheduling problem with sequence-dependent setup times under both the idling and no-idling production cases. The objective is to minimize the maximum completion time or makespan. To solve this important practical problem, a novel estimation of distribution algorithm (EDA) is proposed with a job permutation based representation. In the proposed EDA, an efficient initialization scheme based on the NEH heuristic is presented to construct an initial population with a certain level of quality and diversity. An estimation of a probabilistic model is constructed to direct the algorithm search towards good solutions by taking into account both job permutation and similar blocks of jobs. A simple but effective local search is added to enhance the intensification capability. A diversity controlling mechanism is applied to maintain the diversity of the population. In addition, a speed-up method is presented to reduce the computational effort needed for the local search technique and the NEH-based heuristics. A comparative evaluation is carried out with the best performing algorithms from the literature. The results show that the proposed EDA is very effective in comparison after comprehensive computational and statistical analyses.  相似文献   
144.
一类新型批处理机调度问题的理论分析   总被引:1,自引:0,他引:1  
钢卷在冷轧生产中,为了改进其性能,需要在罩式炉进行退火,退火过程由加热、保温和降温三段组成,而这三段处理时间由于工艺上的要求不能归结为一个时间,这与传统批处理机调度有明显的差别.对新型批处理机的总加权完成时间最小化问题建立了非线性整数规划模型,开发了基于动态规划的启发式算法.通过理论分析,获得该算法的误差性能比为3.对于三段中的某一段板卷的处理时间相同的情况,证明了启发式算法的误差性能比是2,而且证明是紧界.对于三段中的某二段板卷的处理时间相同的情况,证明了启发式算法是最优算法.对启发式算法扩展到带有任意段的加工时间的一般情况进行了性能分析.  相似文献   
145.
We consider the transport of containers through a fleet of ships. Each ship has a capacity constraint limiting the total number of containers it can carry and each ship visits a given set of ports following a predetermined route. Each container has a release date at its origination port, and a due date at its destination port. A container has a size 1 or size 2; size 1 represents a 1 TEU (20‐foot equivalent unit) and size 2 represents 2 TEUs. The delivery time of a container is defined as the time when the ship that carries the container arrives at its destination port. We consider the problem of minimizing the maximum tardiness over all containers. We consider three scenarios with regard to the routes of the ships, namely, the ships having (i) identical, (ii) nested, and (iii) arbitrary routes. For each scenario, we consider different settings for origination ports, release dates, sizes of containers, and number of ports; we determine the computational complexity of various cases. We also provide a simple heuristic for some cases, with its worst case analysis. Finally, we discuss the relationship of our problems with other scheduling problems that are known to be open.  相似文献   
146.
This paper studies appointment scheduling for a combination of routine patients who book well in advance and last‐minute patients who call for an appointment later that same day. We determine when these same‐day patients should be scheduled throughout the day, and how the prospect of their arrivals affects the appointment times of the routine patients. By formulating the problem as a stochastic linear program, we are able to incorporate random and heterogeneous service times and no‐show rates, ancillary physician tasks, and appointment delay costs for same‐day patients who prefer to see the doctor as early as possible. We find that the optimal patient sequence is quite sensitive to the no‐show probabilities and the expected number of same‐day patients. We also develop two simple heuristic solutions to this combinatorial sequencing problem.  相似文献   
147.
为减少对主干网络带宽的消耗,提出了一套数据流量优化方法。首先通过把Peer间的邻居关系明确划分为物理邻居关系和逻辑邻居关系,并用探路者算法来发现Peer的物理邻居,实现拓扑匹配;然后在数据调度算法中,引入通报/退避机制,把大部分数据传输控制在城域网络内部。通过建立模拟仿真环境进行实验分析,证实了该方法可以减少90%以上的网络数据流量。  相似文献   
148.
机器功能主义是功能主义的一种重要形式,是一种对心灵的本体论问题和其它心理属性具有较强的解释力的,克服了逻辑行为主义和类型同一论部分困难的哲学理论。但机器功能主义虽然作为一种主流的理论也有其局限性,例如在解释感受性质等问题上具有不可克服的困难。  相似文献   
149.
基于已设计的机械及气动系统,选择欧姆龙公司CP1HX40DTD PLC研制纸箱包装机控制系统。并进行了I/O点分配、PLC外部接线图及程序控制流程图设计,实现了纸板供送、待装箱产品输送、纸箱装箱成形、喷胶封箱整形等工作过程的自动控制。[HTK]具有很高的可靠性和性价比。  相似文献   
150.
在讨论人脸识别算法的基础上,提出了基于支持向量机算法的人脸识别技术,进而分析了其原理,确定了多项式的核,并利用人脸数据对多项式核的SVM进行训练,根据训练结果进行识别实验,结果表明:SVM与传统方法比较,对人脸具有较高的识别率。  相似文献   
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