基于报童模型的两级供应链回购契约协调研究

研究具有单一供应商和单一销售商的供应链系统回购契约协调机制。分析了报童模型下两级供应链双边际化效应,建立了基于报童模型的分散式系统、集中式系统的供应商、销售商利润模型,讨论了如何通过回购契约来消除"双边际化效应"。结果表明:回购契约的采用使批发价格比不采用契约时的批发价格低,且使订货量增加,从而使供应链的总利润增加,并且减少了缺货带来的损失,同时更好的满足了顾客需要。最终实现了独立个体最优决策与系统最优决策一致化的供应链协调。     

基于损失厌恶型参与者的易逝品供应链价格补贴契约研究

本文运用前景理论,探讨存在缺货损失情况下由损失厌恶型零售商和损失厌恶型供应商组成的供应链价格补贴契约设计。文章研究供应商为损失厌恶型时,损失厌恶型零售商分别在批发价格契约和价格补贴契约下的订货行为。研究结果表明损失厌恶型零售商在批发价格契约下的最优订货量可能偏离系统最优订货量,损失厌恶型供应商通过价格补贴契约可以协调整个供应链。最后通过算例分析,验证了价格补贴契约在协调供应链中的有效性。     

基于多级折扣价格的易逝品订货策略研究

基于价格折扣条件下的报童模型,研究了分销商面向折拐的需求价格曲线.采用呈等差数列下降的多级折扣价格销售产品,以期望利润最大为目标,给出了求解最优折扣次数的算法,进而得到相应的分销商最优订货量.与需求价格曲线的斜率b不变时相比较,b增大对最优订货量无显著影响;b减小对最优订货量有显著影响.     

基于预期的报童问题研究

Koszegi与Rabin认为参照点往往由决策者的理性预期确定，本文选取报童的预期作为参照点，利用参照依赖偏好理论对报童问题进行了研究。研究发现，基于预期的报童的最优订货量不仅与货物销售的概率分布、价格等有关还与报童的损失厌恶程度有关。如果报童是损失厌恶的，报童的订货量要小于经典报童问题的订货量；反之，报童的订货量则大于经典报童问题的订货量，该结论与大部分实证结果是一致的。最后，用算例来验证了文中有关结论的正确性。     

损失厌恶的报童-预期理论下的报童问题新解

本文在决策理论——预期理论框架下,重新对报童问题进行了讨论,给出了损失厌恶的报童的最优订货量的计算公式,此外还进行了必要的比较静态分析。     

一类基于报童模型的新产品推广研究

在易逝品的新产品推广中,市场需求同时受到价格和非价格因素的影响.本文以需求受价格和广告投人影响的报童问题为研究对象,需求函数采用混合形式,研究了一类随机需求下新产品推广的报童问题.建立了需求受价格和广告投入影响的报童问题的数学模型,求解得出最优定价、广告投入和订货量.通过对模型的求解和算例分析,与需求仅受价格影响的报童问题做了比较研究,结果显示,本文建立的模型能为零售商带来更多的利润.     

供应链融资结构视角下的零售商订购策略研究

本文引入供应链融资结构因素，在传统库存管理模型基础上，研究零售商在面临随机市场需求情形下考虑股权和债权等融资方式的订购策略，建立允许零售商延期支付的最优订购模型，利用最优化理论与方法得到了该模型的最优解，证明了最优解的存在性和唯一性，并分析了债权融资比例、价格成本比例系数、销售价格、订货周期、回购价格、进货价格、缺货成本、库存成本、以及融资利率等因素对最优解的影响。进一步，通过数值示例深入探讨具体市场环境下零售商的最优订购量，并进行了敏感性分析。研究发现，债权融资比例、价格成本比例系数、进货价格、订购周期、库存成本与零售商订购量存在负相关关系；缺货成本、回购价格、销售价格与零售商订购量正相关。相关研究结论可以为零售商订购行为提供科学指导，并为其库存管理提供重要决策依据。     

基于CVaR的供应链联合促销的回购契约协调研究

运用CVaR方法,考察了风险中性的供应商和风险规避的销售商联合促销报童类商品的供应链的回购契约协调问题,从讨论中获得一些管理启示。讨论了既定回购契约下渠道成员的最优决策,并分析了回购契约参数、销售商风险规避系数、商品残值和缺货成本等外生参数对渠道成员决策的影响。研究表明传统回购契约不能完成渠道协调,但引入成本分担机制的回购契约能协调不过于规避风险的供应链;指出商品残值和缺货成本对上述结论没有影响,但它们对契约选择空间和能被回购契约协调的供应链的范围具有重要影响。最后,对文中主要结论进行了数值分析。     

基于合同理论的逆向供应链定价策略研究

利用合同理论的方法,借鉴类似回购合同的假设,研究"制造商-零售商"二级供应链中3种不同质量水平的产品回收最优定价问题,以最大化零售商、制造商和供应链的利润。该闭环供应链中只有一个制造商和零售商,零售商负责产品的回收。从分析可知,通过调整参数值,在回收率确定或随机的情况下供应链都可以达到协调,也都可以找到最优订货量和回收价格。研究发现,零售商的最优价格与最优订货量紧密相关,制造商的回收价格并不影响供应链的总体利润。     

季节性易逝品预售与回购联合决策研究

基于季节性易逝品短销售期和短保质期的“双短”特性,其高额利润通常伴随着较大需求不确定性,而且一旦错过销售季节,其极低的残值将导致巨大经济损失与资源浪费.折价预售策略将鼓励消费者提前购买,经销商也可通过预售产品数量的获知来提升市场需求预测的准确性.但消费者在享受预购折价优惠的同时,也可能承担未见到实物产品即进行购买的期望价值损失.此时,经销商若采取回购,则是对消费者利益的直接保障,而在产生回购成本的同时,也可以通过提高预售价格与降低实物订货量等方式带来新增利润.考虑策略型消费者行为,对预售与回购联合策略和单一预售策略进行对比,构建两种策略下的经销商收益模型,并得出相应的最优预售价格与最优订购量.研究发现,当商品单位成本较大或回购价格较低时,预售与回购联合策略的实施能够使经销商获得更优收益,且最优预售价格高于单一预售策略,最优订货量则低于单一预售策略,从而为经销商营销策略选择进行决策支持.     

Power,authority and legitimacy

Management, human resources, organization, control, leadership, etc., all seem to be just so many euphemisms for power, and this suggests a discourse of management and organization that calls things by their proper name. This paper on the contrary stresses the need to resolve the concept of ‘power’ itself into more differentiated notions, and proposes that clarification may be derived from distinctions once explicit in the vocabulary of Classical antiquity, but lost in modern European languages. It argues that nothing but confusion in thinking about organizations, management and legitimation can result from the failure to recognize that the phenomena this vocabulary identifies and distinguishes are irreducibly different.     

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.     

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.     

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.