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161.
In this article, we report and discuss our experience with actor-relational approaches (ARA) in the regeneration of a postwar housing estate in Luchtbal, Antwerp, Belgium. ARA are informed by post-structuralist ideas of space, complexity theory, and actor network theory. Although ARA itself is not new, the application of ARA to deprived area's such as Luchtbal is novel. We report how the approach has been elaborated, its process and outcome. We conclude with our evaluation from an insider's perspective.  相似文献   
162.
Unequal Regionalism: Regional Planning in China and England   总被引:1,自引:0,他引:1  
This paper responds to the revival of regionalism in the past two decades by showing that such a re-emergence is unequal. Comparing the practice of regional planning in China and England, this paper has demonstrated that the party-state in China and the liberal-democratic state in England have responded differently to this revival and developed different framework for regional administration and planning. These variations have not only elaborated planners' concern about planning practice in a ‘context of difference’ from social dimension to geographical variations, but also echoed geographers' affirmation that global trends take on different characters in local setting.  相似文献   
163.
It is often proclaimed that planning concepts serve an innovative function in the political process. They are praised as powerful tools that carry new insights and understandings into policy arenas. By examining the emergence and development of a new planning concept in the Dutch national spatial policy-making process, the deltametropolis concept, this paper questions this position. It argues that new spatial concepts tend to lose much of their innovative capacities when they enter the political arena and become encased in the traditional urban–rural planning discourse, thus reaffirming established planning orientations. The Dutch case of the deltametropolis illustrates that new spatial concepts may entail potential for innovation as much as for lock-in.  相似文献   
164.
本文基于实物期权理论,针对研发项目阶段性特点,结合博弈论的思想,分析了多个研发项目组成的投资状态组合,构建了研发项目动态选择模型。首先,根据研发项目多阶段的特征,利用孪生证券的思想,基于实物期权理论,建立了项目中止决策准则;在此基础上分析研发项目的投资决策状态,建立了二十五个状态的切换场景;然后通过实际算例对模型进行验证和分析,得出了研发项目投资的影响范围概念图,最终实现两个项目的最优投资决策目标。  相似文献   
165.
In semiconductor manufacturing, machines are usually qualified to process a limited number of recipes related to products. It is possible to qualify recipes on machines to better balance the workload on machines in a given toolset. However, all machines of a toolset do not have equal uptimes and may further suffer from scheduled and unscheduled downtimes. This may heavily impact an efficient recipe-to-machine qualification configuration. In this paper, we propose indicators for recipe-to-machine qualification management based on the overall toolset workload balance under capacity constraints. The models, deployed in industry, demonstrate that the toolset capacity must be considered while managing qualifications. Industrial experiments show how capacity consideration leads to an optimal qualification configuration and therefore capacity utilization.  相似文献   
166.
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   
167.
本文在对以顾客为中心的生产组织形式、生产类型和生产方式分析的基础上,提出了以顾客为中心生产的集成计划与控制方法体系、模型和运行机制;同时针对以顾客为中心的联盟合作生产组织形式,给出了相应的合作生产管理策略,从而拓展了现有的生产计划与控制方法,并为以顾客为中心的多企业联盟合作生产目标的实现提供了新的管理策略.  相似文献   
168.
When raw material suppliers of a global supply chain are situated in developing countries, not only will there be long lead times but there could also be a possibility of material losses in transit. The magnitude of the losses will be uncertain and can be significant. We consider the optimization of order quantity decisions in such situations. The long lead times imply that we need to take into account the uncertainty in finished goods demands for which the raw materials are to be ordered. The order quantities have to be optimized carefully as they determine the “real options” that become available later in production plans. Using data from the plywood industry and using stochastic programming we demonstrate a method for solving such problems. The method combines simulation and optimization. An interesting observation we make is that the optimal order quantity of a material need not be monotonic in expected loss of that material. In addition, we offer explanations as to why the expected loss need not be monotonic.  相似文献   
169.
In a job shop, because of large setup times, each operation is assigned to only one machine. There is no alternative routing. In a flexible manufacturing system, each manufacturing operation can often be performed on several machines. Therefore, with automated equipment, the capacity of a machine to perform certain operations is not independent of the capacity of other machines. Often, however, operations managers can use a route‐independent answer to production planning questions. For example, how much can be produced of a certain part type and when are important capacity questions in business negotiations, when the detailed routing and scheduling are not yet of interest or cannot be known. This paper provides a mathematical model for the route‐independent analysis of the capacity of flexible manufacturing systems based on a concept of operation types. An example is provided both to illustrate the use of operation types and to highlight the differences between the traditional route‐dependent and the proposed route‐independent formulations of capacity constraints. Some computational results are also given. Finally, a sensitivity analysis is developed to analyze the feasibility of production plans when production requirements and machine capacities can change.  相似文献   
170.
资源约束型项目调度的优化是一个NP-hard问题,其求解难度随着资源约束项的增多呈指数方式增长,传统的基于Excel表的手工优化方法不能及时计算出有效的资源配置方式,从而影响项目管理人员的资源调度.针对多资源约束型项目调度的优化问题提出基于遗传算法的资源约束型项目调度的优化方法,该算法采用基于活动优先权的十进制编码方式,结合活动的存储邻接矩阵,有效地解决活动调度违例现象;运用优先抢占模式的资源分配方式安排活动资源,避免资源分配中的冲突问题;并为该算法设计了启发式遗传算法的C语言程序,通过计算机的多次迭代运算得出满足资源约束的最优工期.实践结果表明,遗传算法可以快速有效地解决企业项目调度的优化问题,适合在企业项目进度管理中推广运用.  相似文献   
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