连续生产模式下的不常用备件联合采购优化分析

针对连续性生产企业不常用备件管理缺货费用难以确定的实际情况,讨论了服务水平约束的基于随机连续盘点策略的联合补充(s,C,S)随机库存问题,经与单独补充策略相比,发现其经济效益明显。同时对影响备件联合采购费用节约的因素进行敏感性分析,指出了进行此类备件库存优化的方向。     

需求率受推广努力水平影响的新能源汽车租赁系统协调契约

考虑由新能源汽车租赁企业和政府组成的二级系统,在需求率为随机且与推广努力水平相关的市场环境下,建立了新能源汽车租赁企业和政府之间的博弈模型,探讨了分散决策、集中决策、收益共享与成本共担契约下的最优车队配置和推广努力水平,并对三种情形下的最优决策进行了比较和分析。研究结果表明：在分散决策情况下无法实现系统协调,通过引入成本共担与收益共享组合契约,当契约参数满足一定条件时,该组合契约模型不仅可以实现系统协调而且可以使系统成员达到帕累托改进。最后通过算例分析,验证了模型了可靠性和有效性。     

Toward an Application Guide for Safety Integrity Level Allocation in Railway Systems

The work in the article presents the development of an application guide based on feedback and comments stemming from various railway actors on their practices of SIL allocation to railway safety‐related functions. The initial generic methodology for SIL allocation has been updated to be applied to railway rolling stock safety‐related functions in order to solve the SIL concept application issues. Various actors dealing with railway SIL allocation problems are the intended target of the methodology; its principles will be summarized in this article with a focus on modifications and precisions made in order to establish a practical guide for railway safety authorities. The methodology is based on the flowchart formalism used in CSM (common safety method) European regulation. It starts with the use of quantitative safety requirements, particularly tolerable hazard rates (THR). THR apportioning rules are applied. On the one hand, the rules are related to classical logical combinations of safety‐related functions preventing hazard occurrence. On the other hand, to take into account technical conditions (last safety weak link, functional dependencies, technological complexity, etc.), specific rules implicitly used in existing practices are defined for readjusting some THR values. SIL allocation process based on apportioned and validated THR values is finally illustrated through the example of “emergency brake” subsystems. Some specific SIL allocation rules are also defined and illustrated.     

基于元胞自动机的知识型组织中知识传播过程仿真研究

建立了知识型组织中知识型成员间知识传播过程的元胞自动机模型,对知识型成员间隐性知识传播过程的影响因素、传播规律等进行了仿真研究。模拟结果表明:知识型成员间的信任、知识传播者的意愿和影响力与知识传播速度正相关;扁平化的组织结构有利于知识自下而上的传播;当组织知识水平达到最优传播规模时,组织的知识传播瞬时速度将达到最大值。     

考虑订货协调成本与数量折扣的改良品供应链水平协调

在单个供应商与多个销售商构成的二级改良品供应链中,销售商们采用联合补货方式不仅可以分摊订货成本,而且由于订货批量的增加从而更易获得供应商提供的数量折扣合同。建立多个销售商在独立补货与联合补货中的利润水平函数,推导联合补货优于独立补货的充要条件。将销售商之间的联合补货行为转化成多人合作博弈问题,证明博弈具有的基本性质,设计基于博弈核心的利润分配方法。通过数值算例和敏感性分析验证了文中所构建模型的正确性。     

Quality management as a tool for job satisfaction improvement in low-level technology organizations: the case of Ethiopia

Human resources are an important determinant of operational performances as it is crucial for quality improvement. Research suggests that issues related to quality of work life of employees are often overlooked in low technology level organizations in the developing countries. This article aims to investigate the relationship between quality management (QM) practices and job satisfaction (JS) in relation with the Ethiopian manufacturing organizations. Data were collected using a structured survey questionnaire and face-to-face interviews of shop-floor workers. Exploratory and confirmatory factor analysis was used to validate the survey instrument and structural equation modelling was used for the analysis. The findings provide evidence that top management commitment, participation of employees and continuous improvement are significantly and positively associated with JS. However, customer focus has insignificant relationship and surprisingly, teamwork showed unexpected negative relationship with JS. The study provides important insights into the true worth of QM implementation in which it enforces the belief that its practices are the decisive factor in enhancing workplace satisfaction of employees.     

Impact of Water Level Rise on Urban Infrastructures: Washington,DC, and Shanghai as Case Studies

The observed global sea level rise owing to climate change, coupled with the potential increase in extreme storms, requires a reexamination of existing infrastructural planning, construction, and management practices. Storm surge shows the effects of rising sea levels. The recent super storms that hit the United States (e.g., Hurricane Katrina in 2005, Sandy in 2012, Harvey and Maria in 2017) and China (e.g., Typhoon Haiyan in 2010) inflicted serious loss of life and property. Water level rise (WLR) of local coastal areas is a combination of sea level rise, storm surge, precipitation, and local land subsidence. Quantitative assessments of the impact of WLR include scenario identification, consequence assessment, vulnerability and flooding assessment, and risk management using inventory of assets from coastal areas, particularly population centers, to manage flooding risk and to enhance infrastructure resilience of coastal cities. This article discusses the impact of WLR on urban infrastructures with case studies of Washington, DC, and Shanghai. Based on the flooding risk analysis under possible scenarios, the property loss for Washington, DC, was evaluated, and the impact on the metro system of Shanghai was examined.     

基于应对等级的突发事件网络舆情热度分析

突发事件应对等级是应急管理部门采取应对措施的基础,而网络舆情热度是突发事件态势发展的一个重要因素。以应对等级为切入点,构建网络舆情热度评价指标体系,从不同应对等级和事件类型的角度选取8个典型案例,运用GooSeeker等工具进行案例数据挖掘,获得各突发事件的舆情热度值,进一步通过构建突发事件应对等级和舆情热度分析图,发现其存在"一致"和"不一致"的对应关系。研究结果表明：一方面,把突发事件应对等级引入网络舆情热度量表,使舆情热度的评价与政府发布的应对等级建立联系,评价指标更加完善。另一方面,获得不同对应关系下应对等级对舆情热度的指标贡献,对突发事件网络舆情应对提出了更有针对性和科学性的建议。     

语言多样性、信息获取与分析师盈余预测质量

考察了语言多样性对分析师盈余预测质量的影响,以及这种影响如何因员工教育水平的不同而变化.基于中国上市公司的实证检验结果显示,语言多样性显著降低了分析师盈余预测质量,但是随着公司员工受教育水平提高,语言多样性对分析师盈余预测质量的负面影响有所减弱.进一步研究发现,分析师与CEO间的校友关系增强了员工教育水平对语言多样性与分析师盈余预测准确性之间关系的正向调节作用.研究结论一定程度上丰富了分析师私有信息获取及其影响机理以及社会关系等方面的文献,而且还可帮助投资者、监管者等利益相关方更好地理解分析师行为,促进资源合理配置,增强资本市场的有效性等方面具有一定的启示意义.     

Estimation of Deprivation Level Functions using a Numerical Rating Scale

Evaluating and quantifying human suffering in humanitarian operations offers an innovative and potentially powerful way to assess the performance of humanitarian logistics (HL) and help build optimization models. Previous studies have suggested deprivation cost as a metric and have estimated deprivation cost functions for water using willingness‐to‐pay. Our study proposes deprivation levels, defined as the degree of human suffering caused by lack of access to a good or service, and estimates deprivation level functions using a numerical rating scale. Analyzing data collected from respondents with and without disaster experience, we find that individuals in the latter category estimate deprivation differently from the beneficiaries of disaster relief. Our study demonstrates that deprivation levels can be expressed as logistic growth functions with a typical S‐shape, and that these can be integrated into HL optimization models to better account for human suffering.