具有模糊可选时间窗的VRPSPD问题及其混合遗传算法

在经典VRP问题的基础上引入了模糊预约时间和可选时间窗的概念,从顾客满意的角度研究了具有同时配送和回收的车辆路径优化问题,建立了求解此问题的多目标混合整数规划模型,设计了求解此模型的混合遗传算法,并对已有文献中的算例进行了估算求解,估算结果表明,基于2-opt的混合遗传算法在求解没有时间窗约束的VRPSPD方面有比较好的性能.     

Combining common-weights DEA window with the Malmquist index: A case of China’s iron and steel industry

In the conventional data envelopment analysis (DEA) window analysis, a decision-making unit (DMU) in each window is treated as different units in each period so that the evaluation for one unit is performed on different scales over time. This paper proposes a novel window analysis based on common weight across time (CWAT), which evaluates each unit in each window by its common scale independent of time. The model for obtaining common weights is described as linear programming. And the paper suggests the Malmquist productivity index (MPI) on CWAT, CWAT MPI, to analyze productivity change by inheriting the result of window analysis. The numerical experiments are illustrated to examine the validity of CWAT and MPI, and the result shows that the proposed method provides a new evaluation scale compared to previous studies. The proposed model is applied to evaluate the performance of China 45 iron and steel enterprises during 2009–2017. The energy and environmental efficiency are calculated using CWAT, and CWAT MPI analyzes the productivity change.     

Disentangling Treatment Effects of Active Labor Market Policies: The Role of Labor Force Status Sequences

This paper estimates treatment effects of two active labor market policies – a training program and a wage subsidy scheme – on participants' employment probabilities. The analysis is based on unique data from the 18th wave of the Polish Labor Force Survey containing detailed and extensive individual labor force status histories. We discuss two variants of an exact covariate matching procedure adapted to the specific nature of the data. Our study confirms and reinforces a point raised in recent research [Heckman, J.J., Smith, J.A. The Pre-programme Earnings Dip and the Determinants of Participation in a Social Programme: Implications for Simple Programme Evaluation Strategies. The Economic Journal 1999; 109; 313-348., Heckman, J.J., Smith, J.A. The Determinants of Participation in a Social Program: Evidence from a Prototypical Job Training Program. Journal of Labor Economics 2004; 22; 243-298.], that pre-treatment labor force status dynamics play a decisive role in determining program participation. We implement a conditional difference-in-differences estimator of treatment effects based on these individual trinomial sequences of pre-treatment labor market status. The estimator employs a “moving window” technique that nicely controls for changes in the macroeconomic environment over time. Our findings suggest that training raises individual employment probability, while wage subsidies display negative treatment effects for participants in the Polish case.     

有里程和软时间窗约束的开放式多车场集送货一体化车辆路径问题研究

基于现代物流业的现实状况和实际需求,研究了一个带有里程和软时间窗约束的开放式多车场集送货一体化车辆路径问题。给出一个遗传算法对该问题进行求解。在该算法中,为了提高其性能,并全面考虑所有约束,论文采取如下措施:(1)在初始种群形成之前,将各个任务的送货点按时间窗进行排序;(2)在所有任务的一个序列中用里程约束来控制车场的插入,并对软时间窗约束采取加入惩罚的方式解决。最后论文举例对该遗传算法进行说明,并对进一步的研究工作进行了展望。     

精细控压钻井技术在塔里木碳酸盐岩水平井成功应用

介绍了精细控压钻井的概念、工作原理及特点,分析了塔中地区应用精细控压钻井技术的必要性,详述了该技术在塔中多口碳酸盐岩水平井的成功应用案例及其效果,并提出了一些建议。     

茂名电信分公司员工考勤系统

人力资源管理系统是典型的信息管理系统(MIS),其开发主要包括后台数据库的建立和维护以及前端应用程序的开发两个方面。对于前者要求建立起数据一致性和完整性强。数据安全性好的库。而对于后者则要求应用程序功能完备,易使用等特点。     

“破窗效应”在中职教育中的应对措施

破窗效应在中职学校的教育教学中具有非常重要的借鉴作用,针对班级管理中出现的各种漏洞需要及时的矫正和修补,以防止职校学生因缺乏正确的判断力而产生的各种行为、思想上的偏差,造成严重的后果。     

窗墙比对室内热舒适性指标PMV影响的研究

通过建立数学模型进行数值模拟计算,在相同节能改造方案下,对窗墙比与热舒适性之间的变化关系进行了研究。研究表明：窗墙比为0.2时室内舒适性指标较高,但窗墙比为0.32和0.4时的室内舒适性指标基本相同,而且窗墙比为0.32时的室内舒适性指标稍小于窗墙比为0.4时的室内舒适性指标,这与通常窗户越小越舒适的说法有所不同。     

Persistency of window dressing practices in the U.S. repo markets after the GFC: The unexplored role of the deposit insurance premium

We investigate whether the regulatory improvements made in the aftermath of the global financial crisis have been effective in limiting bank downward window dressing by means of repos in the United States. We find that a strict application of the Basel III regulation wipes out incentives to engage in window dressing to bolster the level of leverage Tier 1 ratio at quarter-end. We also show that the persistency of window dressing is related to the computation of the Federal Deposit Insurance Corporation assessment base, which motivates banks to engage in window dressing to reduce the deposit insurance premium.     

Predatory trading,Stigma and the Fed׳s Term Auction Facility

Predatory trading may affect the incentives for banks to raise liquidity in times of financial distress. In these periods, borrowing becomes a signal of illiquidity, exposing borrowers to predatory trading and possible insolvency. A stigma of borrowing thus arises, leading distressed banks to take on more illiquid positions than they would otherwise. The Fed׳s Term Auction Facility (TAF) can alleviate this problem. The TAF׳s competitive auction format allows auction winners to signal that they are illiquid but relatively strong. The TAF may therefore be an effective policy tool during financial crises: by altering the signal value of borrowing, this facility supports the injection of liquidity into distressed banks. In normal times, however, this auction facility becomes counterproductive: by cream-skimming the relatively strong banks, the weakest banks are left as potential prey for predators. This suggests that the TAF is a policy best reserved for times of crisis.