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21.
目前,针对供应链协同度的分析主要集中在单制造商与单供应商之间,为将协同度问题更为一般化,现将供应链协同问题扩展到多供应商、单制造商与多经销商情景中.基于供应链整体运营效率的角度,以制造商为主导,从多经销商、单制造商、多供应商与供应链稳定性四个维度构建供应链协同发展指标体系,将评价指标作为供应链子系统的序参量,运用协同学理论的有序度方法分析供应链子系统的协同性及供应链整体系统的协同度.实例分析说明评价指标体系和协同模型的有效性和可行性,针对协同测度结果提出了供应链系统的协同发展对策.  相似文献   
22.
女娲与伏羲是我国上古神话内容体系中的重要人物,且二者经常相伴出现,粘合度甚高。女娲伏羲神话的形成演变具有一定的历史特点及内在规律,即女娲神话最初以“单性异体”的形貌出现,成为中华民族的创世始祖神;后与社会发展形态适应,出现伏羲女娲相结合的“两性合体”神话,女娲成为伏羲的配偶神;随着男性权力的日益巩固,伏羲成为文明时代的先祖,演变为“三皇”之首,地位不断升高。女娲神话与伏羲神话的发展脉络彼此交错,既自为一体又相互结合。梳理其演变轨迹,分析二神神话不同阶段出现的原因及内涵,有助于探索中国神话的历史文化意蕴及其民族文化精神。  相似文献   
23.
目的探索THADA基因(rs1465618,G/A),(rs2660753,A/G),LOC101929491基因(rs7679673,A/C)和PRNCR1基因(rs1016343,C/T)等4个单核苷酸多态性位点(SNPs)的常见变异与中国北方人群前列腺癌(PCa)的关联。方法采集来自北京医院的138名正常对照和125例PCa患者的血液样本和临床信息。提取样本DNA,用高分辨率熔解曲线分析技术(HRM)对4个SNP(rs1465618,rs2660753,rs7679673和rs101634343)进行基因分型。结果 rs1465618的GG基因型与AG和AA基因型在病例组与对照组间存在显著性差异(P=0.015,OR=1.985;95%CI=1.012~7.732),病例组与对照组间其余3个SNP位点rs2660753(P=0.545),rs7679673(P=0.634),rs1016343(P=0.705)的各个基因型分布没有统计学意义(P0.05)。病例组不同基因型间的表型和环境影响因素分析观察到,rs1465618与常食用蛋类有关(P=0.004),rs2660753与常食用豆制品有关(P=0.04),rs7679673与Gleason评分等级(P=0.034)、PSA浓度等级(P=0.035)及自觉营养状况(P=0.019)均有关,rs1016343与年龄有关(P=0.019)。数量性状分析表明,rs2660753与PCa患者的病程有关(P=0.023),rs1016343与PCa患者食用蛋类数量有关(P=0.002)。结论 rs1465618与中国北方人群的PCa患病显著关联,而rs2660753、rs7679673和rs1016343的常见变异与中国北方人群PCa患病表型和环境影响因素有明显关联。  相似文献   
24.
Over the past 30 years a systemic approach has been applied to complex cases involving intellectual disability and behaviours of concern. This paper describes a model that draws on systemic family therapy and network therapy as well as the use of a reflective team. A single session intervention was provided for families of people with intellectual disability. A systemic consultation was used as a pre‐session meeting for professionals working with the family. The systemic consultation and single session therapy allowed the family and the professional network to gain insight. Involving the professionals in the therapy session also enhanced the alliance between professionals and family. This approach assists everyone involved in the case to find a way to progress.  相似文献   
25.
为实现除尘器区低温省煤器的节能改造,基于FLUENT6.3软件,对除尘器区低温省煤器烟道的流场进行数值模拟研究。研究结果表明:除尘器前烟道内流场严重不均,转弯处有明显的高速区与漩涡区,局部速度高达32 m/s;加装低温省煤器后,两低温省煤器内流场不均,最大速度偏差系数达79.3%,严重影响低温省煤器的换热效果,同时会磨损、冲刷低温省煤器管路,危及低温省煤器的安全;除尘器入口处出现大面积的低速区域,导致进入除尘器后流场紊乱、除尘器电耗高、除尘效率低等现象,除尘器前烟道内整流消涡可以根治除尘器工作效率的问题。  相似文献   
26.
Critical infrastructure systems must be both robust and resilient in order to ensure the functioning of society. To improve the performance of such systems, we often use risk and vulnerability analysis to find and address system weaknesses. A critical component of such analyses is the ability to accurately determine the negative consequences of various types of failures in the system. Numerous mathematical and simulation models exist that can be used to this end. However, there are relatively few studies comparing the implications of using different modeling approaches in the context of comprehensive risk analysis of critical infrastructures. In this article, we suggest a classification of these models, which span from simple topologically‐oriented models to advanced physical‐flow‐based models. Here, we focus on electric power systems and present a study aimed at understanding the tradeoffs between simplicity and fidelity in models used in the context of risk analysis. Specifically, the purpose of this article is to compare performance estimates achieved with a spectrum of approaches typically used for risk and vulnerability analysis of electric power systems and evaluate if more simplified topological measures can be combined using statistical methods to be used as a surrogate for physical flow models. The results of our work provide guidance as to appropriate models or combinations of models to use when analyzing large‐scale critical infrastructure systems, where simulation times quickly become insurmountable when using more advanced models, severely limiting the extent of analyses that can be performed.  相似文献   
27.
Large‐scale outages on real‐world critical infrastructures, although infrequent, are increasingly disastrous to our society. In this article, we are primarily concerned with power transmission networks and we consider the problem of allocation of generation to distributors by rewiring links under the objectives of maximizing network resilience to cascading failure and minimizing investment costs. The combinatorial multiobjective optimization is carried out by a nondominated sorting binary differential evolution (NSBDE) algorithm. For each generators–distributors connection pattern considered in the NSBDE search, a computationally cheap, topological model of failure cascading in a complex network (named the Motter‐Lai [ML] model) is used to simulate and quantify network resilience to cascading failures initiated by targeted attacks. The results on the 400 kV French power transmission network case study show that the proposed method allows us to identify optimal patterns of generators–distributors connection that improve cascading resilience at an acceptable cost. To verify the realistic character of the results obtained by the NSBDE with the embedded ML topological model, a more realistic but also more computationally expensive model of cascading failures is adopted, based on optimal power flow (namely, the ORNL‐Pserc‐Alaska) model). The consistent results between the two models provide impetus for the use of topological, complex network theory models for analysis and optimization of large infrastructures against cascading failure with the advantages of simplicity, scalability, and low computational cost.  相似文献   
28.
本文研究了空气中多种醛酮的测定。目前国内仅对空气中甲醛的测定研究较多,国外报导的方法需用萃取、浓缩等一系列前处理过程,方法麻烦,易引入杂质造成污染。本文报导的方法系采用2.4—二硝基苯肼的甲醇强酸溶液吸收空气中醛酮直接注入液相色谱仪中进行分离测定。研究表明:本法分离效果好,重复性好,方法简便,速度快,测定的精密度和准确度符合微量分析误差的要求。  相似文献   
29.
There are increasing numbers of families in Australia headed by sole parents, but little is known about the experiences of those who also care for a child with a disability. Additional caring responsibilities have previously been shown to impact on the work participation of parents. This study involved qualitative analyses of interview data conducted with sole mothers with school‐aged children with disability (N = 11). Thematic analysis revealed four themes that enabled and supported participation in the workforce: social support; managing appointments; characteristics of the workplace; and the role of the school. Results suggest the importance of practical help from family and friends in facilitating participation in paid employment. Additionally, the importance of flexible appointment scheduling on the part of service providers was highlighted, as well as the importance of workplace flexibility and supportive workplace cultures. Such factors were important in supporting sole mothers to balance work with care, with important implications for personal and family wellbeing.  相似文献   
30.
In electronics Fabs such as semiconductor Fabs and liquid crystal display (LCD) Fabs, which are capital-intensive, finite-capacity planning is critical to achieving full-capacity production and on-time production. However, existing finite-capacity planning methods do not adequately reflect the actual capacity profiles of an electronics Fab. In this paper, we propose a new Fab-level capacity-filtering procedure to generate finite-capacity plan: a backward capacity-filtering procedure for generating finite-capacity release plan. When developing the Fab-level filtering procedures, we use stage-level capacity-filtering algorithms as a key building block. In this study, we enhance the previous capacity-filtering algorithms proposed by one of the authors in order to facilitate the practical requirements of electronics Fabs. We apply the proposed capacity-filtering method to a modern LCD–TFT Fab in Korea. Performance analyses demonstrate that the proposed method is superior to existing methods.  相似文献   
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