基于企业业绩的最优现金周期研究——以我国制造业上市公司为样本

从现金周期对资产周转率和销售利润率正反两方面影响入手,构建基于企业业绩(ROA)最大化的最优现金周期模型,证明最优现金周期的存在性,考察影响最优现金周期的因素,并以我国制造业上市公司为样本,运用主成分分析、多元线性回归等方法,实证检验企业业绩与现金周期的关系,发现存在倒U型关系,即存在最优现金周期,据此针对样本公司给出了相应的对策建议,大多数现金周期长于最优现金周期的公司应适当进行压缩,少部分现金周期短于最优现金周期的公司应适当进行延长,以降低成本,提升各自的业绩。     

印尼J区块层序地层与沉积相特征研究

利用层序地层学理论,对印尼J区块古近系—新近系的层序地层和沉积相特征进行了研究。古近系—新近系可以分为7个中期基准面旋回（SQ1SQ7）和17个短期基准面旋回。SQ1SQ7沉积时期,沉积环境从陆相河流环境逐渐过渡到三角洲环境和浅海环境,再到河流环境,为一完整的水进-水退旋回。中下部层序上升旋回占主体,属海进式沉积组合序列;上部层序下降旋回占主体,多为海退式沉积组合序列。结合层序特征,指出区块西部凸起带SQ5旋回的浊积砂体、基底风化壳、碳酸盐岩台地和东部斜坡带的下切谷为区块的有利勘探区带。研究结果对该盆地的石油勘探具有指导意义。     

桥梁维修寿命周期社会成本及维修决策研究

为了研究桥梁维修决策中桥梁维修期间社会成本核算和最优维修方案选择的问题,文章进行了桥梁维修寿命周期社会成本组成分析、社会成本测度模型分析和维修方案选择模型分析,即在满足桥梁使用功能的基础上,综合考虑桥梁维修的经济成本、社会成本和维修后的再使用寿命,以总成本最小化为目标对不同维修的维修成本和维修后再使用寿命周期进行评估。通过模型分析,选择最优维修方案,提出了以维修寿命周期成本最小化为目标的维修决策模型。     

冷却剂参数对铣槽喷管低周疲劳寿命的影响

采用有限体积流固耦合计算方法、非线性有限元热结构耦合分析方法和局部应变法研究大面积比铣槽喷管三维再生冷却槽道在循环工作条件下的热结构变形与低周疲劳寿命,并对比分析了冷却剂质量流量与入口温度对铣槽喷管疲劳使用寿命的影响。计算结果表明,铣槽喷管热结构响应呈现复杂的三维效应,应变较大位置主要分布在与肋连接的内衬区域,喷管中部的残余应变量最大;冷却槽道低周疲劳寿命分布和热结构响应基本一致,最小寿命位于喷管中部与肋相连的内衬区域燃气侧;随冷却剂质量流量增加,铣槽喷管低周疲劳寿命不断提高;随冷却剂入口温度增加喷管尾部低周疲劳寿命值不断降低,而喷管中前部的低周疲劳寿命值却不断提高,当冷却剂入口温度为280K左右时,本文的铣槽喷管总体使用寿命达到最大。      

独生子女家庭结构演变与养老方案选择研究①——以安徽省为例

独生子女家庭关系简单、脆弱,具有很强的风险性,为此引起学界和政府高度关注。文章利用2010年全国第六次人口普查数据资料,利用生命表方法构建独生子女家庭生命表．并推算丧子家庭、丧偶家庭、单人家庭等各类家庭结构演变趋势。得出：独生子女家庭中,丧子家庭在子女60岁时达到高峰,比例达到3．1％,其中丧子的父母单人家庭比例达到高峰值2．6％,丧子的父母空巢家庭在独生子女50岁达到高峰1．1％：独生子女单亲家庭（丧父或丧母）在独生子女55岁时达到峰值50％。不同的独生子女家庭,有着不同的养老需求,政府应该根据不同的家庭属性设置多样化的养老支持方案。     

Corporate Governance and Firm Performance: A Sociological Analysis Based on Chinese Experience

Based on the 1997-2007 panel data of 676 listed companies and in-depth interviews with the senior executives, independent directors, fund managers and securities analysts of these companies, this paper tries to analyze the relationship between corporate governance and firm performance from a sociological perspective. The results show that the relationship between corporate governance and firm performance in the Chinese institutional environment is sharply different from the predictions of the agency theory. The empirical findings from China lend strong support to the new institutional argument that “best” corporate governance practices are socially “constructed” by various social forces and interests groups in specific social, political and cultural contexts, and how “good” a corporate governance practice is depends to a large extent on whether it fits in with the institutional environment in which it is embedded. There exists no universally “best” model of corporate governance across the world. Our empirical sociological study based on Chinese experience offers new perspectives and evidence for deconstructing the global myth of corporate governance.     

Female entrepreneurship: business,marriage and motherhood in England and Wales, 1851–1911

ABSTRACT

This article offers a new perspective on what it meant to be a business proprietor in Victorian Britain. Based on individual census records, it provides an overview of the full population of female business proprietors in England and Wales between 1851 and 1911. These census data show that around 30% of the total business population was female, a considerably higher estimate than the current literature suggests. Female entrepreneurship was not a uniform experience. Certain demographics clustered in specific trades and within those sectors employers and own-account proprietors had strikingly different age, marital status and household profiles. A woman’s life cycle event such as marriage, motherhood and widowhood played an important role in her decision whether to work, the work available to her and the entrepreneurial choices she could make. While marriage and motherhood removed women from the labour force, they had less of an effect on their levels of entrepreneurship. Women who had young children were more entrepreneurial than those who had none, and entrepreneurship rates rose with the arrival of one child and continued to rise the more children were added to the family.     

Multiple In‐Cycle Transshipments with Positive Delivery Times

We study a centralized inventory sharing system of two retailers that are replenished periodically. Between two replenishments, a unit can be transshipped to a stocked‐out retailer from the other. It arrives a transshipment time later, during which the stocked‐out retailer incurs backorder cost. Without transshipment, backorder cost is incurred until the next replenishment. Since the transshipment time is shorter than the time between two replenishments, transshipments can reduce the backorder cost at the stocked‐out retailer and the holding costs at the other retailer. The system is directed by a centralized inventory manager, who minimizes the long‐run average cost consisting of replenishment, holding, backorder, and transshipment costs. The transshipment policy is characterized by hold‐back inventory levels, which are nonincreasing in the remaining time until the next replenishment. The transshipment policy differs from those in the literature because we allow for multiple transshipments between replenishments, positive transshipment times, and backorder costs. We also discuss the challenges associated with positive replenishment time and develop upper and lower bounds of average cost in this case. Bounds are numerically shown to have an average gap of 1.1%. A heuristic solution is based on the upper bound and differs from the optimal cost by at most this gap.     

The Network Origins of Aggregate Fluctuations

This paper argues that, in the presence of intersectoral input–output linkages, microeconomic idiosyncratic shocks may lead to aggregate fluctuations. We show that, as the economy becomes more disaggregated, the rate at which aggregate volatility decays is determined by the structure of the network capturing such linkages. Our main results provide a characterization of this relationship in terms of the importance of different sectors as suppliers to their immediate customers, as well as their role as indirect suppliers to chains of downstream sectors. Such higher‐order interconnections capture the possibility of “cascade effects” whereby productivity shocks to a sector propagate not only to its immediate downstream customers, but also to the rest of the economy. Our results highlight that sizable aggregate volatility is obtained from sectoral idiosyncratic shocks only if there exists significant asymmetry in the roles that sectors play as suppliers to others, and that the “sparseness” of the input–output matrix is unrelated to the nature of aggregate fluctuations.     

基于PDCA的供应链视角下物流客户服务绩效评价研究

在系统总结国内外相关文献的基础上,设计了基于PDCA循环的供应链视角下物流客户服务绩效评价流程,并针对每个流程给出了控制重点,旨在通过对绩效评价流程的规范管理,不断提高物流客户服务绩效和供应链整体绩效水平。在绩效评价方案设计环节提出了给予供应链整体绩效提升的物流客户服务绩效评价方法和指标体系,在绩效评价方案实施环节给出了应用模糊层次分析法选择物流服务商的步骤。