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141.
Value Stream Mapping (VSM) is a very popular tool in lean environments to represent production flows, mapping value stream of a product or family of products, and helps to identify some types of waste. Although very popular, this tool has some limitations as already described in many publications, especially in terms of restrictions in showing most types of waste as well as in its inability to represent various production routes. The purpose of this study is to introduce the waste identification diagram (WID), a new tool to represent production units with its different forms of waste, which overcomes some VSM limitations. The originality of WID comes from the use of its symbols’ dimensions to convey, in a visual and immediate way, relevant information about a production unit. In this paper, WID is applied on a production unit of a lift manufacturer, for testing its performance and comparing it to VSM. The main findings are that WID is in general more effective than VSM in terms of representation of complex production units and in terms of identification of more forms of waste. WID must however overcome some of its limitations such as the lack of information-flow representation and the links to suppliers and clients.  相似文献   
142.
Risk assessments are crucial for identifying and mitigating impacts from biological invasions. The Fish Invasiveness Scoring Kit (FISK) is a risk identification (screening) tool for freshwater fishes consisting of two subject areas: biogeography/history and biology/ecology. According to the outcomes, species can be classified under particular risk categories. The aim of this study was to apply FISK to the Iberian Peninsula, a Mediterranean climate region highly important for freshwater fish conservation due to a high level of endemism. In total, 89 fish species were assessed by three independent assessors. Results from receiver operating characteristic analysis showed that FISK can discriminate reliably between noninvasive and invasive fishes for Iberia, with a threshold of 20.25, similar to those obtained in several regions around the world. Based on mean scores, no species was categorized as “low risk,” 50 species as “medium risk,” 17 as “moderately high risk,” 11 as “high risk,” and 11 as “very high risk.” The highest scoring species was goldfish Carassius auratus. Mean certainty in response was above the category “mostly certain,” ranging from tinfoil barb Barbonymus schwanenfeldii with the lowest certainty to eastern mosquitofish Gambusia holbrooki with the highest level. Pair‐wise comparison showed significant differences between one assessor and the other two on mean certainty, with these two assessors showing a high coincidence rate for the species categorization. Overall, the results suggest that FISK is a useful and viable tool for assessing risks posed by non‐native fish in the Iberian Peninsula and contributes to a “watch list” in this region.  相似文献   
143.
144.
The Fish Invasiveness Scoring Kit (FISK) is currently one of the most popular pre‐screening tools for freshwater fishes. A recent upgrade has ensured its wider climatic relevance to countries with subtropical regions. This enhancement is of particular importance to Australia, which encompasses tropical, arid, and temperate zones, and where the introduction of non‐native fish species poses a significant risk to biodiversity. In this study, 55 fish species previously evaluated in a U.K.‐based calibration of FISK are reassessed for their potential invasiveness in the Murray‐Darling Basin (MDB; southeastern Australia), the continent's largest catchment encompassing arid and temperate climates. Approximately half of the species were classed as “medium risk” and the other half as “high risk,” and the ≥19 threshold previously identified from the calibration study was confirmed. The three highest scoring species (common carp Cyprinus carpio carpio, goldfish Carassius auratus, and eastern mosquitofish Gambusia holbrooki) were those already present and invasive in the area, whereas nearly half of the tropical and subtropical species had lower scores compared to U.K. assessments, possibly because of climate change predictions of drier conditions across the MDB. There were some discordances between FISK and two Australian‐based assessment protocols, one of which is qualitative and the other represents a simplified version of FISK. Notably, the Australian origins of FISK should provide for an additional reason for further applications of the tool in other RA areas (i.e., drainage basins) of the continent, ultimately encouraging adoption as the country's reference screening tool for management and conservation purposes.  相似文献   
145.
Adapted from the weed risk assessment (WRA) of Pheloung, Williams, and Halloy, the fish invasiveness scoring kit (FISK) was proposed as a screening tool for freshwater fishes. This article describes improvements to FISK, in particular the incorporation of confidence (certainty/uncertainty) ranking of the assessors' responses, and reports on the calibration of the score system, specifically: determination of most appropriate score thresholds for classifying nonnative species into low-, medium-, and high-risk categories, assessment of the patterns of assessors' confidences in their responses in the FISK assessments. Using receiver operating characteristic (ROC) curves, FISK was demonstrated to distinguish accurately (and with statistical confidence) between potentially invasive and noninvasive species of nonnative fishes, with the statistically appropriate threshold score for high-risk species scores being ≥19. Within the group of species classed as high risk using this new threshold, a "higher risk" category could be visually identified, at present consisting of two species (topmouth gudgeon Pseudorasbora parva and gibel carp Carassius gibelio ). FISK represents a useful and viable tool to aid decision- and policymakers in assessing and classifying freshwater fishes according to their potential invasiveness.  相似文献   
146.
Consider a group consisting of S members facing a common budget constraint p'ξ=1: any demand vector belonging to the budget set can be (privately or publicly) consumed by the members. Although the intragroup decision process is not known, it is assumed to generate Pareto‐efficient outcomes; neither individual consumptions nor intragroup transfers are observable. The paper analyzes when, to what extent, and under which conditions it is possible to recover the underlying structure—individual preferences and the decision process—from the group's aggregate behavior. We show that the general version of the model is not identified. However, a simple exclusion assumption (whereby each member does not consume at least one good) is sufficient to guarantee generic identifiability of the welfare‐relevant structural concepts.  相似文献   
147.
This paper extends Imbens and Manski's (2004) analysis of confidence intervals for interval identified parameters. The extension is motivated by the discovery that for their final result, Imbens and Manski implicitly assumed locally superefficient estimation of a nuisance parameter. I reanalyze the problem both with assumptions that merely weaken this superefficiency condition and with assumptions that remove it altogether. Imbens and Manski's confidence region is valid under weaker assumptions than theirs, yet superefficiency is required. I also provide a confidence interval that is valid under superefficiency, but can be adapted to the general case. A methodological contribution is to observe that the difficulty of inference comes from a preestimation problem regarding a nuisance parameter, clarifying the connection to other work on partial identification.  相似文献   
148.
R&D项目中止决策的小波网络模式识别   总被引:14,自引:1,他引:14  
如何科学、合理、有效地识别和中止那些行将失败或没有前途的 R&D项目 ,对于企业成功地进行技术创新、建立和保持竞争优势 ,显然具有十分重要的理论价值和实践意义 .本文根据中止决策的实质及模式识别的基本原理 ,探讨了定量地中止 R&D项目的一般模式识别程序 .同时 ,基于小波基具有很强的自适应数据和函数变化的能力 ,进一步研究给出了一种基于小波网络的 R&D项目中止决策分析模式识别新方法 ,并在最小均方能量准则下 ,采用相应的共轭梯度学习算法求解子波函数线性组合的尺度和时延参数 ,以及神经网络的权值 .本研究不仅克服了现有 R&D项目中止决策分析技术在构造与求解模型方面的某些局限性 ,并且为R&D项目的跟踪管理提供了一种新的理论依据 ,为具体决策单位和政府有关部门对正在实施的 R&D项目作中止决策提供了一种可操作的决策方法和程序  相似文献   
149.
王安石精神主要表现为:追求真理的无畏战斗精神,富国强兵的爱国主义精神,革故鼎新的革新精神,务实有为的实干精神。弘扬王安石的精神,要善于从历史与现实的比较中借鉴,积极推进当代中国的改革和现代化建设大业,从传统与时代的结合中创新,造就具有鲜明时代特色的民族精神。  相似文献   
150.
栗原小获、伊丹才让、南永前三位当代少数民族诗人诗作的外部风格的共同点是对本民族有着深厚的感情;诗作整体热烈,激情豪迈。又由于诗人的生存环境,所受本民族文化影响的差异等原因,诗作呈现的语言风格十分别异。三位诗人诗作文本的文化超越性是诗作抒情主体所袁现的人类之爱,是抒情主体在诗中所表现的超越民族、超越个体的文化关怀和文化命运感。  相似文献   
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