带有限等待的动态HFS调度的拉格朗日松弛算法

作为基于最优化的近似算法,分析了拉格朗日松弛算法的分解策略,设计了算法的实现优化过程.针对从钢铁生产提炼出的带有限等待时间要求的动态HFS调度,采用基于工件解耦的分解策略,应用拉格朗日松弛算法进行求解,以最小化总加权完成时间和工件等待惩罚之和.该算法将工件耦合约束松弛到目标函数中,将形成的松弛问题分解成多个更易求解的工件级子问题,进而利用动态规划求解这些子问题,通过拉格朗日乘子的更新迭代过程获得原问题的近优解.对不同问题规模的测试结果表明,该算法能在较短的计算时间内得到较好的近优解,说明了拉格朗日松弛算法求解等待时间受限的HFS调度的可行性和有效性.     

Cross-cultural aging in cognitive and affective components of subjective well-being.

The present study examined age and cultural differences in cognitive and affective components of subjective well-being. A sample of 188 American and Chinese young and older adults completed surveys measuring self-life satisfaction, perceived family's life satisfaction, positive affect, and negative affect. Across cultures, older adults reported lower negative affect than did young adults. Americans reported higher self-life satisfaction, perceived family's life satisfaction, and positive affect than did Chinese. In addition, perceived family's life satisfaction was more related to self-life satisfaction for Chinese than for Americans. Findings are discussed in light of socioemotional selectivity theory and theories on culture and self-construal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A constraint-based approach for the shift design personnel task scheduling problem with equity

This paper presents an industrial problem which arises in a company specialized in drug evaluation and pharmacology research. The aim is to build employee timetables covering the demand given by a set of fixed tasks. The optimality criterion concerns the equity of the workload sharing. A solution to this problem is the assignment of all tasks whose resulting working shifts respect tasks requirements as well as legal and organizational constraints. Scheduling problems usually consider a fixed set of shifts which have to be assigned to a given number of employees whereas in our problem shifts are not fixed and are deduced from the task assignment. In the following, we refer to this problem as the shift-design personnel task scheduling problem with an equity criterion (SDPTSP-E), in reference to the shift minimization personnel task scheduling problem (SMPTSP). Even if the SDPTSP-E is related to several problems, none of them allow to grasp its full complexity. Consequently, we propose a dedicated method based on constraint programming. Several branching and exploration strategies are proposed and tested.     

Approximating Satisfiable Satisfiability Problems

We study the approximability of the Maximum Satisfiability Problem (MAX SAT) and of the boolean k -ary Constraint Satisfaction Problem (MAX k CSP) restricted to satisfiable instances. For both problems we improve on the performance ratios of known algorithms for the unrestricted case. Our approximation for satisfiable MAX 3CSP instances is better than any possible approximation for the unrestricted version of the problem (unless P=NP). This result implies that the requirement of perfect completeness weakens the acceptance power of non-adaptive PCP verifiers that read 3 bits. We also present the first non-trivial results about PCP classes defined in terms of free bits that collapse to P. Received August 1997; revised February 1999.     

Need satisfaction and adolescent pathological internet use: Comparison of satisfaction perceived online and offline

This study investigated the role of need satisfaction in adolescent pathological internet use by comparing the differences in the perception of need satisfaction online and offline. A compensatory satisfaction theory was proposed to explain the role of need satisfaction online in pathological internet use. Cross-sectional data were collected from 4559 Chinese students from 12 to 20 years of age. The participants responded to an anonymous questionnaire concerning their internet use behavior, their perceived level of need and their need satisfaction online and offline. The results of structural equation modeling showed that pathological internet use was predicted not by the level of need, but rather by the way in which the need was satisfied. Need satisfaction perceived online predicted adolescent pathological internet use positively, while need satisfaction perceived offline predicted pathological internet use negatively. Furthermore, the direct comparison of need satisfaction online and offline showed that the advantage of need satisfaction online completely mediated the effect of unsatisfied need on adolescent pathological Internet use. Enlightenment of the theory and implications for efforts to encourage offline activities are discussed.     

The relationship between voluntary employer changes and perceived job stress in Taiwan.

Although the career strategy of voluntary employer changes has been recognized, it remains unclear whether those adopting such a strategy pay a price of higher job stress or experience a benefit of lower job stress. Two competing hypotheses of the relationship between voluntary employer changes and perceived job stress were proposed. Data from a survey of master's of business administration degree holders in Taiwan supported the hypothesis of a negative relationship. Those with more voluntary employer changes perceive lower job stress. This finding expands the knowledge of the link between behavioral characteristics and job stress. The situations for this finding are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A hybrid Bayesian-frequentist predictive design for monitoring multi-stage clinical trials

Abstract

In this article, we propose a hybrid-Bayesian frequentist approach using a Bayesian sequential prediction of the index of satisfaction. For interim analysis that addresses prediction hypothesis, such as futility monitoring with delayed outcomes, the prediction of satisfaction properly accounts for the amount of data remaining to be observed in a clinical trial and has the flexibility to incorporate additional information via auxiliary variables. The prediction of satisfaction design guarantees the type I error rate and does not require intensive computation or comprehensive simulation. The design is retrospectively applied to a lung cancer clinical trial.     

Production system-based simulation for backward on-line job change scheduling

Backward on-line job change scheduling, referring to the on-line job change scheduling of a current processing step to satisfy the job change schedule of the subsequent processing step, is a common problem in modern Fabs. In this research, the production system-based simulation methodology is proposed to solve the backward on-line job change scheduling problem. This simulation is processed by the state change that is caused by an execution of the operator, and it finds the schedule with the best handle values considering the current status. Several simulation runs with diverse handle values were required to find the best values because the status of the shop floor can change dynamically. To validate the simulation, this production system-based simulation is applied to the on-line job change scheduling of a tire belt processing step as part of the tire manufacturing process.     

建成环境满意度对乡村新型社区居民自评健康的影响分析——以成都市远郊 4 个社区为例

在健康城市研究领域,对健康城市社区建成环境的研究居多,而对健康乡村社区建成环境的研究不足,将个体自评健康应用到健康乡村的研究对促进健康村镇研究具有积极意义。选取四川省成都市蒲江县4个新村社区作为乡村新型社区典型案例,开展以村民个体为单位的问卷调查,获取411份问卷样本数据。基于此,分析乡村新型社区居民自评健康结果的特点,探析建成环境对居民自评健康的影响。研究显示,在乡村新型社区建成环境中,显著影响居民自评健康的环境感知指标为：住房质量、交通条件设施、体育健身设施、幼托设施、村庄内绿化和卫生环境的满意度。结合田野调查和深度访谈,从健康角度提出了乡村社区规划设计的建议。