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41.
This paper presents an effective and efficient method for solving a special class of mixed integer fractional programming (FP) problems. We take a classical reformulation approach for continuous FP as a starting point and extend it for solving a more general class of mixed integer (0–1) fractional programming problems.To stress the practical relevance of the research we focus on a real-life application in paper production industry. The constantly advancing physical knowledge of large scale pulp and paper production did have a substantial impact on an existing DSS in which mixed integer (0–1) fractional programming is introduced. We show that the motivation to solve a real-life fractional programming problem can provide the basis for a new approach in a new context that has an added value of its own, even outside the given application area. We describe the main characteristics of the DSS, the necessity to develop a non-iterative solution procedure and demonstrate both the effectiveness and efficiency of the proposed approach from practical data sets.  相似文献   
42.
Economic issues linked to career counseling are a cause for concern to policy makers in developed countries because they expect career practitioners to provide evidence of the efficiency of career counseling interventions. The aim of this study was to test an individual evaluation method mixing time series (outcomes) and life narrative (processes). The method used 5 items related to 1 client's career decision self‐efficacy and studied the evolution of those items throughout the intervention of 1 career counselor (43 days). Changepoint analysis helped in identifying the changes that have to be taken into account for time series and which are contextualized in the client's verbatim analysis. This mixed method highlighted that the career counselor's intervention increased the client's career decision self‐efficacy. Practitioners could use the methodology proposed in this article to evaluate their interventions. They could also report their practice to clients, employers, and decision makers.  相似文献   
43.
国家主体型、国家—个人主体型和个人主体型三种不同类型的程序主体性,反应了诉讼程序从国家控制到个体的人的自由的发展趋势。现代诉讼程序强调程序主体的个人主体性,个体的人应当成为程序独立的自主、自在性主体,这就需要其在诉讼程序中具有独立的属己利益支撑。民事诉讼程序应当淡化国家色彩,以个人的程序利益保障为基点,实现个人的独立性程序地位,进而使民事诉讼程序获得真正的独立性。  相似文献   
44.
We address the staff rostering problem in call centers with the goal of balancing operational cost, agent satisfaction and customer service objectives. In metropolitan cities such as Istanbul and Mumbai, call centers provide the transportation of their staff so that shuttle costs constitute a significant part of the operational costs. We develop a mixed integer programming model that incorporates the shuttle requirements at the beginning and end of the shifts into the agent-shift assignment decisions, while considering the skill sets of the agents, and other constraints due to workforce regulations and agent preferences. We analyze model solutions for a banking call center under various management priorities to understand the interactions among the conflicting objectives. We show that considering transportation costs as well as agent preferences in agent-shift assignments provides significant benefits in terms of both cost savings and employee satisfaction.  相似文献   
45.
This paper investigates an integrated production and transportation scheduling problem in an MTO supply chain. A harmony search-based memetic optimization model is developed to handle this problem, in which certain heuristic procedures are proposed to convert the investigated problem into an order assignment problem. A novel improvisation process is also proposed to improve the optimum-seeking performance. The effectiveness of the proposed model is validated by numerical experiments. The experimental results show that (1) the proposed model can solve the investigated problem effectively and that (2) the proposed memetic optimization process exhibits better optimum-seeking performance than genetic algorithm-based and traditional memetic optimization processes.  相似文献   
46.
The cost of an uncontrolled incursion of invasive alien species (IAS) arising from undetected entry through ports can be substantial, and knowledge of port‐specific risks is needed to help allocate limited surveillance resources. Quantifying the establishment likelihood of such an incursion requires quantifying the ability of a species to enter, establish, and spread. Estimation of the approach rate of IAS into ports provides a measure of likelihood of entry. Data on the approach rate of IAS are typically sparse, and the combinations of risk factors relating to country of origin and port of arrival diverse. This presents challenges to making formal statistical inference on establishment likelihood. Here we demonstrate how these challenges can be overcome with judicious use of mixed‐effects models when estimating the incursion likelihood into Australia of the European (Apis mellifera) and Asian (A. cerana) honeybees, along with the invasive parasites of biosecurity concern they host (e.g., Varroa destructor). Our results demonstrate how skewed the establishment likelihood is, with one‐tenth of the ports accounting for 80% or more of the likelihood for both species. These results have been utilized by biosecurity agencies in the allocation of resources to the surveillance of maritime ports.  相似文献   
47.
The purpose of this article is to obtain the jackknifed ridge predictors in the linear mixed models and to examine the superiorities, the linear combinations of the jackknifed ridge predictors over the ridge, principal components regression, r?k class and Henderson's predictors in terms of bias, covariance matrix and mean square error criteria. Numerical analyses are considered to illustrate the findings and a simulation study is conducted to see the performance of the jackknifed ridge predictors.  相似文献   
48.
随着网络视频运营商收费节目试看的兴起,而节目试看对网络视频运营商诸如市场规模,利润等市场策略的影响所知甚少。本文在考虑网络用户情绪效用情况下,通过构建高质量视频运营商首播节目与后来跟进的低质量视频运营商播出该节目的博弈模型,研究高质量视频运营商首播节目之前提供节目试看对两个运营商收费模式下的节目最优收费价格和免费模式下的最优嵌入广告量以及视频节目提供模式选择的影响。研究表明,高质量视频运营商在节目首播之前提供节目充分试看能够实现节目最优收费价格最高,利润最大,因此节目充分试看是其最优策略;并且低质量运营商在其单位广告收益与用户单位广告"成本"满足一定条件下,高质量运营商提供的节目的充分试看能够减少低质量运营商总利润,因此避免低质量视频运营商搭乘节目试看的顺风车;高质量视频运营商提供节目充分试看情况下,高质量视频运营商只采取收费模式为其最优市场策略,低质量视频运营商采取免费模式为其最优市场策略。本文的研究成果对网络视频运营商日常运营有一定的管理学启示与应用价值。  相似文献   
49.
刑事审后程序是指除审判监督程序外刑事判决生效后一系列程序的总称,包括刑事执行程序、被害人的权利保障程序以及刑罚被执行完毕人员的前科消灭程序等内容。刑事诉讼法学界除了对作为刑事审后程序重要内容的刑事执行程序研究较为充分外,还没有人对刑事审后程序作过系统的专门研究。对刑事审后程序进行系统的理论研究,特别是建立和完善被害人损害赔偿制度和被害人国家补偿制度,建立刑罚被执行完毕人员前科消灭的法律制度,不仅有助于完善我国刑事诉讼法,也有助于社会主义和谐社会的构建。  相似文献   
50.
In this article, to reduce computational load in performing Bayesian variable selection, we used a variant of reversible jump Markov chain Monte Carlo methods, and the Holmes and Held (HH) algorithm, to sample model index variables in logistic mixed models involving a large number of explanatory variables. Furthermore, we proposed a simple proposal distribution for model index variables, and used a simulation study and real example to compare the performance of the HH algorithm with our proposed and existing proposal distributions. The results show that the HH algorithm with our proposed proposal distribution is a computationally efficient and reliable selection method.  相似文献   
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