Loss-averse测度下考虑政府补贴的双第三方回收再制造闭环供应链

以制造商、零售商及两个第三方回收商构成的再制造闭环供应链为背景,使用Loss-averse函数测度零售商的风险规避特性、古诺(Cournot)模型刻画第三方回收商的竞争特性,将政府补贴作为内生变量,构建了第三方回收再制造闭环供应链模型,分析了风险特性、政府补贴及竞争特性对供应链的影响,证明了收益费用共享契约可以克服双重边际效应和风险规避效应,优化loss-averse测度的考虑政府补贴的双第三方回收再制造闭环供应链;最后,通过仿真研究,验证了该模型的有效性及实用性,得出了政府补贴、风险特性、竞争特性等与供应链成员期望利润等之间的关联关系,为再制造产业发展的科学决策提供决策支持和参考。     

Downside-Risk测度下三层供应链协调契约研究

以制造商是风险中性、分销商和销售商具有下行风险特性的三层供应链系统为背景,研究了风险规避特性对供应链协调性的影响,证明了Downside-Risk测度下三层供应链不协调。依据供应链协调的基本思想和方法,将补偿政策与收益共享、产品回购等契约相结合,建立了Downside-Risk测度下三层供应链协调模型,设计了风险共享契约,既能满足下行风险约束,又保证供应链参与方利润均有增量,实现了Downside-Risk测度下供应链的协调和风险控制,最后通过算例验证了契约的可行性和有效性。     

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。     

专利保护下闭环供应链的再制造策略研究

在专利完善市场,受专利保护的原制造商享有产品再制造的专有权利,只有获得原制造商的专利许可,第三方再制造商才能进行旧产品的回收再制造。本文分析了受专利保护下原制造商所采取的不同再制造策略:阻止旧产品再制造(N策略)、原制造商自己再制造(O策略)和许可第三方再制造商进行再制造(A策略),并建立了由零售商负责旧产品回收的闭环供应链模型。通过比较发现,只有在第三方再制造商处理旧产品的节省成本足够低时,受专利保护的原制造商才会选择许可第三方再制造商进行旧产品再制造。     

零售商与第三方回收下闭环供应链回收与定价研究

基于市场细分建立了零售商回收与第三方回收废旧产品情形的闭环供应链决策模型,通过对两种情形决策变量的求解与比较,讨论了回收努力程度和产品定价的区别,分析了制造商与零售商的利润随消费者偏好系数的变化规律.结果表明:与第三方回收相比零售商回收情形回收努力程度较高,但零售商不具有参与闭环供应链的积极性;第三方回收情形零售商具有参与闭环供应链的积极性,但回收努力程度较低;第三方回收情形新制造与再制造产品的零售价均高于零售商回收情形的零售价,零售商回收对消费者有利.     

第三方回收商领导型两级闭环供应链的回收与定价策略

与一般废旧产品的回收产品再制造相比,废弃电子电器产品回收拆解后需要兼顾产品与零部件再制造,从而减少电子电器产品对环境的污染,推进资源的重复利用。为了探讨第三方回收商的回收与定价策略对供应商和制造商的影响,本文构建由单一供应商、制造商和第三方回收商组成的两级再制造闭环供应链,建立Stackelberg博弈模型,研究两级再制造情形下和仅产品再制造情形下回收商的有效回收比例、回收定价和回收努力程度等决策,并对两种再制造情形下供应链各成员的决策与收益进行对比分析。研究发现：对于回收商而言,回收数量、有效回收比例的增加有助于回收商获得更多的额外收益。如果在仅产品再制造情形下的有效回收比例较大,回收商的决策和收益主要取决于无效零部件的回收价。当无效零部件的回收价较低时,回收商在仅产品再制造情形下的决策和收益更优;反之,回收商在两级再制造情形下的决策和收益更优。对于其他供应链成员而言,两种再制造策略都能够降低供应商和制造商的定价,促进市场需求的增加。具体而言,不同的再制造策略对批发价、零售价和市场需求的影响与有效回收比例和无效零部件的回收价密切相关。     

双边网络环境下考虑消费者行为的两期供应链回收定价模型研究

闭环供应链管理是促进经济与环境双重效益提高的有效途径，已成为电子废弃物回收利用的核心解决方案。本文考虑包括制造商和第三方回收平台组成的闭环供应链模型，构建了完全垄断的两期动态博弈双边平台，分析和比较了分散决策和集中决策下闭环供应链的最优回收定价和利润，并利用收益共享契约来实现闭环供应链帕累托改进，最后用数值仿真分析了再制造比例、用户对平台利润贡献率对供应链利润的影响，验证了契约协调的有效性。研究表明：交叉网络外部性强度与平台向两边征收的价格、各主体利润和总体利润存在相关关系。第三方回收平台通过补贴消费者可有效增加回收效用，提高了回收率与消费者回收意识。实施收益共享契约的互利性使各主体积极主动实施契约，提高了各方与总体利润。     

混合需求下考虑专利保护因素的闭环供应链定价与协调

在新产品需求为随机需求,再制造产品需求受销售价格影响的混合需求条件下,以博弈论为主要工具,研究了受专利保护的再制造闭环供应链的定价与协调问题,分析了集中决策和分散决策两种情形下的新产品最优订购量、废旧产品最优回收价格、最优专利许可费用、再制造品最优零售价格以及供应链的最优利润,并通过收益分享一费用分担契约对闭环供应链系统进行了协调,并通过数值算例验证了集中决策和分散决策情形下再制造成本节约对供应链成员的最优决策和利润的影响,以及收益分享.费用分担契约对闭环供应链的协调效果。研究表明再制造受专利保护的情况下,原制造商能通过专利许可费来影响第三方再制造商回收的废旧产品的回收价格和回收量,进而去影响原制造商和第三方再制造商的收益。     

闭环供应链上的回收激励契约设计与政府补贴再制造政策的优化

废旧工业产品的回收再制造活动具有较大的正向外部经济特性,常常导致企业从事该项活动的动力不足。从节约资源和保护环境的目的出发,各国政府大都制定了给予补贴以鼓励回收再制造活动的政策。而且新产品和再制造产品一般具有一定的感知价值差异,可能会影响到再制造成本优势的发挥。将政府也作为一个决策主体,建立了以政府为领导者、制造商和再制造商、回收商为跟随者的三级非线性闭环供应链上的Stackelberg主从博弈模型,其中嵌套了基于委托代理关系分析基本技术框架的再制造商对回收商回收努力的最优激励契约。分析求解了政府和制造商、再制造商等的最优决策。政府的补贴政策将有效提高再制造品的竞争优势,同时有效降低废旧产品的掩埋等处理成本,有利于生态环境的保护。政府最优补贴下再制造商对回收商的最优激励机制设计可以有效提高废旧工业品的回收再制造效率。新产品和再制造产品的相互替代程度将间接影响到政府的最优补贴决策。同时通过数值分析得到再制造的比较成本优势对闭环供应链决策的影响。可供政府有关部门在政策制定以及闭环供应链上的企业决策时参考。     

渠道结构对第三方负责回收闭环供应链的影响

研究了四种渠道结构对第三方负责回收闭环供应链的影响。分别建立了四种再制造闭环供应链模型,给出了这些模型的最优零售价格、批发价格、回收比例以及各方的最优利润,并对这四种模型进行了比较分析。研究发现回收方制定回收策略时需考虑回收品价格和回收努力成本的大小,闭环供应链中任意两方的战略联盟有利于另外一方利润的增加,而且,闭环供应链中的任意两方都有战略联盟的动机。     

Criteria for selecting a production control philosophy

Logistic objectives constitute a compromise between having short leadtimes and a low volume of work in progress on the one hand and a high resource loading and due date obligation on the other. Miscellaneous production planning approaches offered today provide different combinations of logistic objectives for satisfying a manufacturing strategy. To combine the strength of the various approaches into a unified system, a new approach based on a dynamic and distributed production planning methodology is proposed. To customize the approach, various analyses and specifications have to be made and for that reason some important characteristics and criteria for analysing production control philosophies will be given.     

The social construction of the meaning of acute stressors: a qualitative study of the personal accounts of police officers using a stress counselling service

The police profession is one in which acute stressors are encountered more frequently than in other occupations. Using the personal accounts of 35 police officers attending an in-house stress counselling clinic, the aim of the present study was to provide a qualitative examination of how the institutional context of policing influenced the ways in which acute stressors signified to individual police officers experiencing felt distress. Using the framework of Rational Emotive Behaviour Therapy as an analytical tool, it is argued that beliefs contributing to the experience of felt distress are related to the way in which policing as both an identity and an activity is constructed through the police organizational culture. Not only do these constructions influence the ways in which officers perceive themselves and their environments, but they also operate at the collective level to 'normalize' some emotional responses and to 'pathologize' others which, it is argued, could impact upon the outcomes of interventions such as stress counselling.     

The moderating role of social support in Karasek's job strain model

This paper examines whether social support is a boundary-determining criterion in the job strain model of Karasek (1979). The particular focus is the extent to which different sources of social support, work overload and task control influence job satisfaction, depersonalization and supervisor assessments of work performance. Hypotheses are tested using prospective survey data from 80 clerical staff in a university setting. Results revealed 3-way interactions among levels of support (supervisor, co-worker, non-work), perceived task control and work overload on levels of work performance and employee adjustment (self-report). After controlling for levels of negative affect in all analyses, there was evidence that high levels of supervisor support mitigated against the negative effects of high strain jobs on levels of job satisfaction and reduced reported levels of depersonalization. Moreover, high levels of non-work support and co-worker support also mitigated against the negative effects of high strain jobs on levels of work performance. The results are discussed in terms of the importance of social support networks both at, and beyond, the work context.     

Job insecurity, coping resources and personality dispositions in occupational strain

This paper presents research on the relationships between the work-related stressor of perceived job insecurity and various indicators of occupational strain, taking into account employees' personality dispositions (trait negative and positive affectivity) and coping resources. Respondents were 222 Australian public servants surveyed during organizational restructuring that involved downsizing and threat to job certainty. The research was formulated within an adaptation of Osipow, Doty, and Spokane's (1985) framework of stress-strain-coping that included the possible direct as well as moderating effects of personality dispositions in reporting occupational strain (Parkes, 1990). Findings from hierarchical regression analyses indicate consistent significant independent effects of personality dispositions, coping resources and perceived job insecurity on various indicators of strain. There was also support for the moderating roles of negative affectivity and self-care in the relation between perceived job insecurity and physical strain. Implications for the role of dispositional factors, especially negative affectivity, and the utility of various coping resources in accounting for occupational strain in times of threatened job security are discussed.     

Introduction to Special Section on Sensitivity Analysis and Summary of NCSU/USDA Workshop on Sensitivity Analysis

This guest editorial is a summary of the NCSU/USDA Workshop on Sensitivity Analysis held June 11–12, 2001 at North Carolina State University and sponsored by the U.S. Department of Agriculture's Office of Risk Assessment and Cost Benefit Analysis. The objective of the workshop was to learn across disciplines in identifying, evaluating, and recommending sensitivity analysis methods and practices for application to food‐safety process risk models. The workshop included presentations regarding the Hazard Assessment and Critical Control Points (HACCP) framework used in food‐safety risk assessment, a survey of sensitivity analysis methods, invited white papers on sensitivity analysis, and invited case studies regarding risk assessment of microbial pathogens in food. Based on the sharing of interdisciplinary information represented by the presentations, the workshop participants, divided into breakout sessions, responded to three trigger questions: What are the key criteria for sensitivity analysis methods applied to food‐safety risk assessment? What sensitivity analysis methods are most promising for application to food safety and risk assessment? and What are the key needs for implementation and demonstration of such methods? The workshop produced agreement regarding key criteria for sensitivity analysis methods and the need to use two or more methods to try to obtain robust insights. Recommendations were made regarding a guideline document to assist practitioners in selecting, applying, interpreting, and reporting the results of sensitivity analysis.     

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.     

Distinguishing traumatic, vicarious and routine operational stressor exposure and attendant adverse consequences in a sample of police officers

Problems in studying occupational stress within the police service are identified and the paucity of work on operational duties as potential stressors are discussed. The present study reports the results of a factor analysis of operational stressors (N = 601 serving British police officers) that revealed three factors: exposure to death and disaster; violence and injury; sexual crime. These were demonstrated to be reliable scales and were included in logistic regression models together with a range of demographic and psychological variables. Models were applied to men and women separately, which showed there to be different predictors of the likelihood of suffering distress (measured by the General Health Questionnaire, GHQ) in terms of the officer's gender and operational role. Overall the model for women officers was better at predicting psychological distress than that for men. These findings are related to aspects of the police occupational culture. Further discussion is offered that conceptualizes police operational stressors as traumatic, routine and vicarious. Finally, some implications are drawn for the provision of stress intervention in the light of this differentiation.     

Dermal Uptake of 18 Dilute Aqueous Chemicals: In Vivo Disappearance‐Method Measures Greatly Exceed In Vitro‐Based Predictions

Average rates of total dermal uptake (K_up) from short‐term (e.g., bathing) contact with dilute aqueous organic chemicals (DAOCs) are typically estimated from steady‐state in vitro diffusion‐cell measures of chemical permeability (K_p) through skin into receptor solution. Widely used (“PCR‐vitro”) methods estimate K_up by applying diffusion theory to increase K_p predictions made by a physico‐chemical regression (PCR) model that was fit to a large set of K_p measures. Here, K_up predictions for 18 DAOCs made by three PCR‐vitro models (EPA, NIOSH, and MH) were compared to previous in vivo measures obtained by methods unlikely to underestimate K_up. A new PCR model fit to all 18 measures is accurate to within approximately threefold (r = 0.91, p < 10^?5), but the PCR‐vitro predictions (r > 0.63) all tend to underestimate the K_up measures by mean factors (UF, and p value for testing UF = 1) of 10 (EPA, p < 10^?6), 11 (NIOSH, p < 10^?8), and 6.2 (MH, p = 0.018). For all three PCR‐vitro models, log(UF) correlates negatively with molecular weight (r² = 0.31 to 0.84, p = 0.017 to < 10^?6) but not with log(vapor pressure) as an additional predictor (p > 0.05), so vapor pressure appears not to explain the significant in vivo/PCR‐vitro discrepancy. Until this discrepancy is explained, careful in vivo measures of K_up should be obtained for more chemicals, the expanded in vivo database should be compared to in vitro‐based predictions, and in vivo data should be considered in assessing aqueous dermal exposure and its uncertainty.     

Systems Resilience for Multihazard Environments: Definition,Metrics, and Valuation for Decision Making

The United Nations Office for Disaster Risk Reduction reported that the 2011 natural disasters, including the earthquake and tsunami that struck Japan, resulted in $366 billion in direct damages and 29,782 fatalities worldwide. Storms and floods accounted for up to 70% of the 302 natural disasters worldwide in 2011, with earthquakes producing the greatest number of fatalities. Average annual losses in the United States amount to about $55 billion. Enhancing community and system resilience could lead to massive savings through risk reduction and expeditious recovery. The rational management of such reduction and recovery is facilitated by an appropriate definition of resilience and associated metrics. In this article, a resilience definition is provided that meets a set of requirements with clear relationships to the metrics of the relevant abstract notions of reliability and risk. Those metrics also meet logically consistent requirements drawn from measure theory, and provide a sound basis for the development of effective decision‐making tools for multihazard environments. Improving the resiliency of a system to meet target levels requires the examination of system enhancement alternatives in economic terms, within a decision‐making framework. Relevant decision analysis methods would typically require the examination of resilience based on its valuation by society at large. The article provides methods for valuation and benefit‐cost analysis based on concepts from risk analysis and management.     

UNIX系统性能监控简述及shell系统资源统计程序

本文简要阐述了unix系统中(主要以IBM的AIX为例)进行系统性能管理的几种命令行工具,并通过编写shell实例程序,运用其中提到的工具实现系统资源利用率的统计程序,为做好unix系统管理和调优提供参考.