考虑跨渠道退货的双渠道供应链最优策略

基于零售商线上线下销售与消费者退货并存的双渠道供应链,构建考虑退货的双渠道供应链定价模型以及考虑跨渠道退货策略的双渠道供应链定价决策模型。通过理论分析和数值实验对比,研究集中决策与分散决策下的零售商最优定价策略以及总利润的变化情况,同时分析在不同退货策略下顾客偏好以及退货率对零售商定价和收益的影响。结果表明：零售商渠道的最优价格设置与顾客对渠道的偏好成正比,与退货率成正比。当顾客对某一渠道偏好程度高时,分散决策下的利润要高于集中决策,并且随着该渠道退货率的提高,这种利润差距会进一步扩大,因此零售商应实施分散决策的渠道策略,鼓励线上线下两个渠道进行竞争,从而获得更大的收益。从仿真结果可以看出,对于一般的服装产品,提供跨渠道退货服务的零售商总利润更高,在一定条件下跨渠道服务水平的投入会增加零售商的收入,但这种投入应该控制在一个合理的水平上,并保持服务与顾客回报之间的正相关关系。     

含有自治复原退货物流的单周期库存问题研究

研究电子商务模式中含有自治复原退货物流的单周期库存控制问题.在考虑退货价对需求影响的基础上,通过引入可再售退货产品率,将退货品分为可再销售和不可再销售两部分进行分析,以销售商的利润最大化为目标,借助报童模型建立了自治复原退货物流下考虑退货价对需求影响的单周期库存模型,分析模型中最优订货量、退货价和利润的求解方法,通过数值分析探讨模型中各参数(退货价对需求的影响因子、退货率、可再售退货率)对利润、最优退货价和订购量大小的影响以及造成这些影响的原因.研究结果发现,商家应该在制定策略时考虑退货价对需求的影响,并大胆地提出和宣传自己的退货政策,以增加顾客对退货价的敏感度,从而获取更多的利润.     

考虑无缺陷退货下零售商转运的供应链回购契约研究

针对由单个供应商和同一连锁企业的两个零售商组成的供应链系统中无缺陷退货问题。在随机需求下,假设零售商努力水平与无缺陷退货率成反比,以及两个零售商之间可以相互进行库存转运,建立了期望收益决策模型。通过比较集中决策和分散决策下零售商订货量及各方期望利润,确定了零售商最优订货量和最优努力水平,并提出了改进的差异化回购契约,算例分析表明,改进的差异化回购契约能够达到供应链协调。     

考虑退货的定价和订货优化及信息发布美化策略

考虑顾客由感知差异引起的退货行为，以及促销期与日常销售期不同的行为特点，对日常销售期和促销期顾客购买率和退货率分别进行了解析表述.在此基础上分析了确定需求下信息发布美化策略对最大利润的影响.建立了随机需求下在线零售商的期望利润模型，对定价和订货量进行联合优化.最后通过算例分析了在感知价值和感知差异服从更为一般的分布形式且存在相关性条件下，最优策略下的预期利润随信息发布美化程度的变化规律，以及相关性对信息发布美化策略有效性的影响.研究结果表明，基于感知价值和感知差异构建的购买率和退货率模型可较好解释已有实证研究结果，以此为基础对定价和库存进行联合优化更符合实际，优化条件下的最大利润随信息发布美化程度的提高先增后降，取得最大利润的信息美化值促销期大于日常销售期，且线性相关程度越高的产品取得最大利润的信息美化值越大。     

考虑退货价格的易逝品供应链协调性研究

考虑由一个制造商和一个零售商组成的供应链,制造商以批发价格为零售商提供一种易逝品,零售商再以零售价格将产品销售给顾客;零售商以一定的退货价格回收顾客的退货产品,制造商对零售商的顾客退货产品及销售季节结束后的剩余产品进行回收,零售商的退货价格不仅对产品的需求有影响,而且对顾客的退货率也产生影响.在这样的条件下,建立了需求不确定环境下顾客退货及制造商回收的模型,结果表明,制造商简单回收顾客的退货产品和销售季节结束后的剩余产品并不能实现供应链协调,而基于回馈与惩罚策略的制造商回收策略能够实现供应链的协调.最后,给出了供应链协调下的模型优化方法,并以数值实例计算了易逝品供应链协调下的最优退货价格和最优订货量,并分析了各种参数变动对最优退货价格、最优订货量和集中式供应链最优利润的影响.     

考虑跨渠道退货的双渠道闭环供应链决策研究

双渠道闭环供应链存在制造商网络直销渠道和零售商实体店零售渠道。消费者会对购买不满意的产品进行退货，由于网上商店购买的产品缺乏现场体验故退货率较高。相比线下实体商店，线上退货流程更为复杂，这往往容易影响消费者购物体验。因此本文设计考虑跨渠道退货的双渠道闭环供应链结构，并分析跨渠道退货率以及渠道消费偏好对供应链的决策影响，基于Stackelberg博弈和Nash均衡博弈理论，从集中式决策与分散式决策两方面研究不同闭环供应链结构下的定价决策与利润分配，并结合数值算例进行分析。研究结果表明，跨渠道退货率以及消费者渠道偏好对闭环供应链的定价策略以及利润分配等决策具有显著影响。     

考虑退货风险的制造商双渠道供应链定价决策研究

针对事前不确定性导致的退货问题，从消费者行为出发，建立考虑定价差异和退货风险双重因素的市场需求函数，通过Stackelberg博弈模型研究四种不同市场需求情形在不同定价模式下双渠道供应链的最优决策。在数值仿真部分，对不同情形决策之间比较、供应链收益进行比较分析。研究表明：电子渠道销售价格与电子渠道的市场基本需求成正比，批发价和传统渠道销售价格与传统渠道的市场基本需求成正比，实体店体验服务水平和传统渠道的市场基本需求的关系（线性关系）则根据某些条件而定；退货风险对供应链决策的影响与定价模式、市场需求影响因素相关；制造商偏好于定价不相等模式，零售商偏好于定价相等模式；退货风险与定价差异对供应链成员收益的影响与定价模式相关，对整体供应链收益的影响与定价模式和退货率大小有关。     

考虑消费者后悔的库存及退货策略研究

消费者预期后悔对在线零售商的决策有显著影响.在考虑消费者预期后悔、需求不确定性以及是否提供退货的情况下,构建了零售商定价和库存优化模型.研究发现,当零售商不提供退货时,消费者的保留价格、零售商的最优价格、最优订货量和期望利润均随着迟疑后悔强度的减弱或购买后悔强度的增加而减小.零售商提供全额退款提高消费者的保留价格,并使得零售商在一定条件下不受消费者预期后悔的影响.零售商是否提供全额退款受到消费者预期后悔、消费者退货成本、产品边际成本和回收残值的综合影响:当退货成本较小且预期后悔满足一定条件时,提供退货是有利的;否则,提供全额退款会降低零售商的期望利润.研究强调在制定退货决策时考虑消费者预期后悔和退货成本的重要性.     

基于库存价值改变和随机需求的经济订货批量模型

大多数库存研究的重点都集中在各种复杂的限制条件和模型的变换上.没有考虑到库存本身可能发生贬值或增值的情况,而实际中库存本身常常会发生价值变化.针对以往库存模型中没有考虑库存价值变化的问题,提出了在需求为随机连续分布、库存价值发生变化情况下的单周期经济订货批量模型,给出了最优订货策略.模型中以先进先出为假设条件,基于报童模型的思想,以订货量为决策变量、期望收益为目标函数,结合随机需求的分布情况得到最优订货量和最大期望收益,并给出了相应的数学证明.通过算例对模型进行说明,并对影响最优订货批量和最大期望收益的各个参数进行敏感性分析.     

基于信息更新与服务水平约束的供应链订货及协调决策

研究由一个供应商和一个零售商及一组顾客组成的单周期供应链系统。供应商向零售商提供两次订 货机会,零售商根据第一阶段的订货情况及市场信号,对需求信息进行更新预测,确定第二阶段是否需要补货。首先,通过分析顾客购买与退货决策,确定产品的最优零售价格与退货价格。其次,对零售商的订 货策略进行研究,以两阶段利润之和最大化为目标函数,引入服务水平约束,确定了零售商第一阶段和第 二阶段的最优订货量,并探讨了市场信号和服务水平约束对零售商最优订货策略及期望利润的影响。结果表明,当目标服务水平设定较低时,零售商的订货策略与不设定服务水平约束时的情形相同;但是无论是高目标服务水平还是低目标服务水平,若二次订货时点上的市场信号为低值时,零售商无需二次订货,而若此时点的市场信号为高值时,零售商需要进行二次订货,目标服务水平的高低将对第二次的订货量产生影响。最后,证明了基于差别定价的回购契约能够实现上述供应链系统的协调。     

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.