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51.
With time-based competition and rapid technology advancements, effective manufacturingscheduling and supply chain coordination are critical to quickly respond to changing marketconditions. These problems, however, are difficult in view of inherent complexity and variousuncertainties involved. Based on a series of results by the authors, decomposition and coordination byusing Lagrangian relaxation is identified in this paper as an effective way to control complexity anduncertainty.A manufacturing scheduling problem is first formulated within the job shop context withuncertain order arrivals, processing times, due dates, and part priorities as a separable optimizationproblem. A solution methodology that combines Lagrangian relaxation, stochastic dynamicprogramming, and heuristics is developed. Method improvements to effectively solve large problemsare also highlighted. To extend manufacturing scheduling within a factory to coordinate autonomicmembers across chains of suppliers, a decentralized supply chai  相似文献   
52.
介绍ERP内涵,以正确认识ERP,ERP具有个性的和动态的特征,运用ERP必须进行业务流程重组。  相似文献   
53.
本文用高等几何的知识和有关三角函数的重要不等式十分简捷地解决了椭圆内接n边形的最大面积问题。  相似文献   
54.
Shape skeletonization (i.e., medial axis extraction) is powerful in many visual computing applications, such as pattern recognition, object segmentation, registration, and animation. In this paper, the authors expand the use of diffusion equations combined with distance field information to approximate medial axes of arbitrary 3D differential properties. It offers an alternative solids represented by polygonal meshes based on their but natural way for medial axis extraction for commonly used 3D polygonal models. By solving the PDE along time axis, this system can not only quickly extract diffusion-based medial axes of input meshes, but also allow users to visualize the extraction process at each time step. In addition, the proposed model provides users a set of manipulation toolkits to sculpt extracted medial axes, then use diffusion-based techniques to recover corresponding deformed shapes according to the original input datasets. This skeleton-based shape manipulation offers a fast and easy way for animation and deformation of complicated mesh objects.  相似文献   
55.
This paper reflects on my experience as an insider researcher attempting to use critical systems ideas and practices to promote quality improvement in a university engineering department. Reflection is a key part of learning. This paper is intended to contribute to critically, self-reflective learning for the community of systems practitioners. These reflections on my questions about participation, ethics, politics of process, and the choices and actions resulting from them may help others to formulate their own. The complexity of systems practice places substantial demands on the researcher, particularly in the case of insider, practitioner research. Nevertheless, the exploration of critical systems approaches to critique boundaries and structure ‘problems’ in the core aspects of higher education in locally meaningful ways should continue. While demanding, it still can work to promote learning about authentic quality.  相似文献   
56.
57.
计算机技术人才是我区“实现跨越式发展和长治久安”的战略性目标基本资源,是我区实现“信息化带动工业化”的人才支撑。我校担负着培养本地区计算机人才的主要任务。文章分析了就我校计算机专业课教学中目前存在的诸多“不相适应”现象,做了调查分析,并依此提出了几点教学革新建议。  相似文献   
58.
We consider the stability of a random Riccati equation with a Markovian binary jump coefficient. More specifically, we are concerned with the boundedness of the solution of a random Riccati difference equation arising from Kalman filtering with measurement losses. A sufficient condition for the peak covariance stability is obtained which has a simpler form and is shown to be less conservative in some cases than a very recent result in existing literature. Furthermore, we show that a known sufficient condition is also necessary when the observability index equals one.  相似文献   
59.
In the present paper, we focus on constructive spherical codes. By employing algebraic geometry codes, we give an explicit construction of spherical code sequences. By making use of the idea involved in the proof of the Gilbert-Varshamov bound in coding theory, we construct a spherical code sequence in exponential time which meets the best-known asymptotic bound by Shamsiev and Wyner.  相似文献   
60.
高荪芳 《山西科技》2007,(6):80-80,90
教师与学生之间的良好关系是教学过程顺利进行的重要因素。在教学过程中培养学生认识事物的能力和素养,培养具有良好情商的社会主义新人,这是教师义不容辞的责任。  相似文献   
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