A visual planning solution to streamline the processes of hybrid cross-dockings

Cross-docking is a logistic strategy widely adopted both in manufacturing and distribution contexts. Despite the huge number of researches on this topic, most of them remain rather theoretical as they do not pay enough attention to operational aspects and daily functioning patterns of cross-dockings. This article aims at introducing a new focus for cross-docking research by proposing a visual planning solution to manage daily operation of a manufacturing cross-docking. By avoiding complex optimization algorithms and by adopting concepts belonging to the lean management theory, the article shows the potential of visual planning techniques to improve performance of cross-dockings. Starting from a specific industrial context, the shipping warehouse of an Italian company of the oil andand gas sector, a visual management methodology has been proposed to support the operation of cross-dockings. Although developed in a particular context, the proposed methodology and its underlying principles are to be considered general and potentially applicable to a wide range of cross-dockings. The methodology fully exploits an analytical tool, namely, the Safety Margin coefficientthat could be used for capacity planning purposes and to evaluate quantitatively the system performance at a given time instant.     

Let's Call it Quits: Break‐Even Effects in the Decision to Stop Taking Risks

“Chasing” behavior, whereby individuals, driven by a desire to break even, continue a risky activity (RA) despite incurring large losses, is a commonly observed phenomenon. We examine whether the desire to break even plays a wider role in decisions to stop engaging in financially motivated RA in a naturalistic setting. We test hypotheses, motivated by this research question, using a large data set: 707,152 transactions of 5,379 individual financial market spread traders between September 2004 and April 2013. The results indicate strong effects of changes in wealth around the break‐even point on the decision to cease an RA. An important mediating factor was the individual's historical long‐term performance. Those with a more profitable trading history were less affected by a fall in cash balance below the break‐even point compared to those who had been less profitable. We observe that break‐even points play an important role in the decision of nonpathological risk takers to stop RAs. It is possible, therefore, that these nonpathological cognitive processes, when occurring in extrema, may result in pathological gambling behavior such as “chasing.” Our data set focuses on RAs in financial markets and, consequently, we discuss the implications for institutions and regulators in the effective management of risk taking in markets. We also suggest that there may be a need to consider carefully the nature and role of “break‐even points” associated with a broader range of nonfinancially‐focused risk‐taking activities, such as smoking and substance abuse.     

基于活动敏感性的动态缓冲监控方法研究

缓冲监控问题对于企业成功应用关键性项目管理,提高项目进度管理绩效和确保项目按时完工,都至关重要。本文针对现有缓冲监控方法在项目进度监控中所存在的忽视内部情况的问题,引入项目进度风险分析方法中的活动敏感性信息。研究了动态环境下活动敏感性指标的计算和监控阀值的设定,在缓冲的黄区监控中集成了考虑活动敏感信息的动态监控过程。在综合考虑缓冲指标和活动关联度指标的监控指标体系,综合设置各指标的监控阀值的基础上,提出了基于活动敏感性信息的关键链动态缓冲监控方法。最后通过一个算例将所提方法与现有方法进行比较,实验结果表明,合理设置活动关联度的监控阀值后,所提方法在总赶工时间、总赶工活动数、超计划完工次数以及监控负荷这四个绩效方面的结果更优。     

作业成本动因选择、合并与评价的系统方法构建

目前学术界关于作业成本动因选择与合并的研究,缺乏对动因留选与留选个数的探讨,而关于对成本动因选择合并的评价的研究未见。可以通过聚类分析建立模型,得到成本动因的相关类,再结合主成分分析指导留选动因的个数,最终确定留选动因,并首次建立评价动因选择与合并优劣性的主成分分析模型。实证分析表明,此系统方法更好地解决了成本动因选择与合并的问题,相同数据下该方法比矩阵理论与距离聚类分析结果更优,作业成本管理系统的复杂性与信息成本显著降低。本文为作业成本动因的选择与合并以及评价提供了一套系统方法。     

并行工程产品开发过程定量化建模与计划制订

由于现有的一些并行工程定量化模型中修改设计微循环的细节特征描述得还不够充分 ,本文提出了一种新的基于产品 -工艺设计活动对网络的定量化模型来描述并行工程产品开发过程 ,并且给出了产品 -工艺设计活动对平均持续时间与产品或工艺设计活动资源占用率的计算方法 .在此基础上 ,将并行工程产品开发过程的计划制订问题建模成一个有资源约束的项目调度问题 .与其它此类问题不同的是 ,在本文中 ,分配给产品开发项目的各类资源的数量不是事先给定的 ,而是与最优产品开发计划一起获得的 ,所以这是一个资源分配与计划制订的集成优化问题 .本文提出了一种新的基于分枝定界的算法来解决此问题并引入一个启发式规则来提高算法的搜索效率     

Health Risk Assessment of a Modern Municipal Waste Incinerator

During the modernization of the municipal waste incinerator (MWI, maximum capacity of 180,000 tons per year) of Metropolitan Grenoble (405,000 inhabitants), in France, a risk assessment was conducted, based on four tracer pollutants: two volatile organic compounds (benzene and 1, 1, 1 trichloroethane) and two heavy metals (nickel and cadmium, measured in particles). A Gaussian plume dispersion model, applied to maximum emissions measured at the MWI stacks, was used to estimate the distribution of these pollutants in the atmosphere throughout the metropolitan area. A random sample telephone survey (570 subjects) gathered data on time-activity patterns, according to demographic characteristics of the population. Life-long exposure was assessed as a time-weighted average of ambient air concentrations. Inhalation alone was considered because, in the Grenoble urban setting, other routes of exposure are not likely. A Monte Carlo simulation was used to describe probability distributions of exposures and risks. The median of the life-long personal exposures distribution to MWI benzene was 3.2·10^–5 g/m³ (20th and 80th percentiles = 1.5·10^–5 and 6.5·10^–5 g/m³), yielding a 2.6·10^–10 carcinogenic risk (1.2·10^–10–5.4·10^–10). For nickel, the corresponding life-time exposure and cancer risk were 1.8·10^–4 g/m³ (0.9.10^–4 – 3.6·10^–4 g/m³) and 8.6·10^–8 (4.3·10^–8–17.3·10^–8); for cadmium they were respectively 8.3·10^–6 g/m³ (4.0·10^–6–17.6·10^–6) and 1.5·10^–8 (7.2·10^–9–3.1·10^–8). Inhalation exposure to cadmium emitted by the MWI represented less than 1% of the WHO Air Quality Guideline (5 ng/m³), while there was a margin of exposure of more than 10⁹ between the NOAEL (150 ppm) and exposure estimates to trichloroethane. Neither dioxins nor mercury, a volatile metal, were measured. This could lessen the attributable life-long risks estimated. The minute (VOCs and cadmium) to moderate (nickel) exposure and risk estimates are in accord with other studies on modern MWIs meeting recent emission regulations, however.     

论栗木文化意蕴的形成及其表现

森林文化是近十年来一个新兴的学术研究领域,它吸引了自然科学和人文社会科学方面的一批学者,经过不懈的努力,使这片园地结出了丰硕的果实。这些研究除了从整体上对森林制度、生态文明、森林文化进行探讨外,还具体到单种树木,比如松柏文化、杨柳文化、槐文化等。栗木文化隶属于森林风俗文化范畴,栗木及其果实具有很强的实用性,正因为如此,中国古人赋予了它较为丰富的文化内涵,特别是生殖崇拜主题。这些文化观念又往往通过宗社祭祀和其他民俗活动具体形象地呈现出来,深刻反映出古代人们的土地崇拜、生殖崇拜等观念,对我们了解古代文化以及当前有关民间遗俗有重要的参考价值。     

权力机关撤销具体行政行为探析

从抽象行政行为和具体行政行为二者的关系及权力机关的职能诸方面看 ,权力机关撤销具体行政行为十分必要 ,撤销具体行政行为的原则方法必须适当     

论学术道德建设的运行机制

学术道德建设的机制是多种机制的整合。学术道德建设主要应形成学术道德教育培养机制、学术道德舆论引导机制和学术活动规范综合运行机制。这些机制的良性运行 ,才能促进学术活动的健康有序发展     

宋代蹴鞠运动的繁荣及成因

宋代的蹴鞠运动和前代相比,已经有了很大的变化,不仅在以宫廷为代表的上流社会中流行,并且也在民间盛行,甚至军队中的蹴鞠活动也脱离"讲武之有材"的元貌。由于向着休闲和娱乐的方向发展,在民间的蹴鞠运动甚至出现了职业化的发展势头。宋代蹴鞠运动之所以出现如此繁荣局面的原因,除两宋社会阶级、社会生活变化的推动外,最重要的是,宋代人们的思想观念已经发生了极大的改变:蹴鞠运动不再是卑贱者的行为。