Job stress, job strain, and psychological withdrawal among Dutch university staff: towards a dualprocess model for the effects of occupational stress

This study examined the antecedents of job strain (emotional exhaustion, health complaints) and withdrawal behaviour (e.g. lowered organizational commitment) among a cross-sectional sample of 131 academic staff members of the law department of a large Dutch university. Conservation of resources theory (Hobfoll, 1989) provided the theoretical background for this study. Strains and withdrawal behaviours were expected to be most prominent among those who reported having few resources and/or who reported high job demands. Structural equation modelling revealed that this was indeed the case. As predicted, differential patterns of effects emerged for job demands and job resources. Analysis of the effects of four job-specific stressors revealed that especially the structural aspects of a staff member's teaching task (e.g. the number of students in their classes) contributed strongly to perceived job demands. Theoretical and practical implications of the study are discussed.     

Applicability of a Neuroprobabilistic Integral Risk Index for the Environmental Management of Polluted Areas: A Case Study

Recently, we developed a GIS-Integrated Integral Risk Index (IRI) to assess human health risks in areas with presence of environmental pollutants. Contaminants were previously ranked by applying a self-organizing map (SOM) to their characteristics of persistence, bioaccumulation, and toxicity in order to obtain the Hazard Index (HI). In the present study, the original IRI was substantially improved by allowing the entrance of probabilistic data. A neuroprobabilistic HI was developed by combining SOM and Monte Carlo analysis. In general terms, the deterministic and probabilistic HIs followed a similar pattern: polychlorinated biphenyls (PCBs) and light polycyclic aromatic hydrocarbons (PAHs) were the pollutants showing the highest and lowest values of HI, respectively. However, the bioaccumulation value of heavy metals notably increased after considering a probability density function to explain the bioaccumulation factor. To check its applicability, a case study was investigated. The probabilistic integral risk was calculated in the chemical/petrochemical industrial area of Tarragona (Catalonia, Spain), where an environmental program has been carried out since 2002. The risk change between 2002 and 2005 was evaluated on the basis of probabilistic data of the levels of various pollutants in soils. The results indicated that the risk of the chemicals under study did not follow a homogeneous tendency. However, the current levels of pollution do not mean a relevant source of health risks for the local population. Moreover, the neuroprobabilistic HI seems to be an adequate tool to be taken into account in risk assessment processes.     

基于卓越绩效模式的供应链质量成本优化研究

本文以供应链质量成本为主要研究对象,分析归纳供应链质量成本研究现状,结合卓越绩效模式方法,提出质量成本核算体系,建立基于卓越绩效模式的供应链质量成本模型。通过一个应用案例,采用遗传算法求解,证明该方法使供应链成本得到了优化。     

The Pursuit of Productivity

This study names a pantheon of entrepreneurs and managers who have introduced a range of far‐reaching productivity innovations throughout modern history. The thread tying together all of the innovations, in whatever sector of the economy one examines, is the theory of swift, even flow. The study argues why swift, even flow explains the power and long‐lasting nature of these innovations and why other factors thought by some to affect productivity fall short.     

基于Hawkes过程的国际原油市场与中国股票市场大幅波动联动性研究

考虑国际原油市场与中国股票市场之间的大幅波动存在联动性,本文采用二维标值Hawkes模型对2007年至2019年8月的布伦特原油期货和沪深300指数的日度数据中大幅波动的单市场延续和跨市场传染的传播特性进行建模。实证结果表明：(1)Hawkes过程可以较好地拟合国际原油和中国股市之间大幅波动的自激发和互激发效应,并捕捉资产收益率在时间和空间上的聚集性、持续性和溢出性;(2)原油市场和中国股市的大幅波动均存在较强的自激发效应;(3)原油市场和中国股市之间大幅波动的互激发效应具有统计意义上的显著性,但在实际影响方面相比于自激发效应更为微弱。本研究对股票市场建设、资产配置和风险防范均有一定意义。     

基于需求预测的两级动态配送路径优化研究

针对传统响应式配送难以应对海量动态客户需求的困境,在此提出基于需求预测的两级动态配送路径优化方法。利用历史数据从需求预测、需求聚类和需求配额三个维度,处理电商物流配送过程中的动态需求;建立基于需求预测的单阶段和多阶段两级车辆配送路径优化模型,并针对问题特性利用分支定界算法与CW-禁忌搜索算法生成两个阶段的最优配送路径。最后结合实验案例对模型与算法的有效性进行验证,试验结果表明本文设计方法具有较好的动态场景适应度和客户响应能力。     

创新驱动下光伏产业供应链的竞协研究——基于政府竞争政策

将政府竞争政策与技术创新因素引入到两级多晶硅供应链博弈模型中,研究不同情形下政府竞争奖励与技术创新努力水平对于各级制造商最优利润的影响。构建关于硅片批发价与光伏系统销售量的利润博弈模型,求得了各级制造商的最优利润函数,并通过实证研究分析了竞争与协调两种情形下竞争政策与技术创新因素对于各级制造商最优与整体供应链总利润的影响。研究表明：(1)政府竞争政策有利于增加制造商的利润;(2)技术创新努力水平的升高可以较快的增加制造商的利润;(3)与竞争情形相比,协调情形下各制造商的利润及整个供应链总利润更高。     

回收竞争下考虑CSR行为的闭环供应链定价决策及协调

研究考虑企业社会责任(CSR)行为的闭环供应链定价决策及协调问题,分别构建了单个第三方回收及两个第三方回收竞争下的闭环供应链博弈模型,分别从企业与消费者两个视角分析了CSR投入对供应链成员的定价策略及系统总收益的影响,并建立了基于“收益共享”与“回收成本共担”相结合的契约协调模型。研究表明,两个第三方回收商间的适度竞争不仅可以降低产品价格、提升废旧产品回收效率,同时对提高企业的CSR投入水平以及收益水平也起到积极的促进作用。最后,在契约参数的可行性范围内,“收益共享-成本共担”契约在使供应链总收益达到最大的同时,还成功改善了每个成员企业的收益。     

我国股票市场收益率偏度对风险补偿的影响研究

收益率与波动率之间的关系(风险补偿)在金融资产定价和风险管理中至关重要,但二者之间的研究却一直没有定论。金融理论表明为正向关系,但实证却往往得到相反的结果。众所周知,尖峰厚尾以及负偏是收益率的典型特性。这些内在属性对风险补偿无疑有着重要的影响。本文研究表明,收益率的负偏和尖峰厚尾会导致风险补偿系数减小,进而导致风险补偿系数在实证当中的不确定性。虽然各个行业的夏普比率相差无几,我国股票市场的第“I”类、第“II”类风险补偿以及风险价格在不同行业之间存在较大的差异,且三者随着投资期限的增长,分别有下降、上升和轻微上升的趋势。     

基于服务化的制造企业与服务提供商的演化博弈分析

制造企业从传统制造向服务型制造转变是其转型升级、提升竞争力的重要路径之一。而企业在转型过程中受自身资源约束,往往需要服务提供商的配合。本文在构建制造企业与服务企业的收益函数基础上,建立两方非对称演化博弈模型,探究制造企业与服务提供商合作实施服务化策略的规律,并运用MATLAB仿真,深入研究相关因素对制造企业与服务提供商合作实施服务化策略的影响作用。研究表明,制造企业对服务提供商所提供服务的依赖度、服务化制造企业与未服务化制造企业间的差异化竞争度、双方合作前后的收益和成本、合作不成功造成的损失、收益的分配等因素是合作意愿的重要影响因素,且差异化竞争度比服务依赖度对合作意愿的影响作用更强烈、与收益相比博弈主体对成本的变化更敏感、服务提供商更易动摇合作的意愿、存在最优的收益分配系数使制造企业与服务提供商采取合作策略的意愿最强。