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91.
Management of imprecision and uncertainty for production activity control   总被引:2,自引:0,他引:2  
The operational levels of production management, often called production activity control (PAC) or manufacturing process control, require increasing reaction capabilities in order to adapt the workshop management to the changes of its environment. It often implies giving more responsibilities to the low decision levels. However, the management of the corresponding degrees of freedom is generally unusual. In such a situation, decision support systems (DSSs) provide a way to reconcile the satisfaction of mid-level objectives and the reaction requirements. A conceptual model is described that provides a design framework for a PAC DSS. Since the available knowledge lies mainly in expertise, a DSS has been implemented using a knowledge-based system. The uncertainty and imprecision of the managed information led to the use of fuzzy logic as a modeling tool. Moreover, various inference semantics have been implemented in the expert rules because different kinds of reasoning have been identified. Two versions of the DSS are described and several examples of implemented reasoning processes are developed.  相似文献   
92.
滕洪孟  林明霞  娄云鹏 《黄金》2004,25(11):1-5
介绍了作业成本法的概念、计算原理、核算过程及数学模型;通过应用作业成本法对焦家金矿高水材料厂产品成本的计算、分析,其计算结果与实际相符;为管理者决策提供了依据。  相似文献   
93.
Abstract This research makes use of learning time intensity, burst evaluating equations, and state denotation approaches to evaluate the learning time characteristics of students. Through comparing learning time intensity, six burst styles and three diligence styles are categorized. From the statistical results and interaction content analysis, some pedagogical phenomena were found. The first finding is that the more diligent learners were, the higher the quality and quantity of their interaction. The second is that learners whose learning time intensity was mainly located in the early period of the course and whose interaction content included many complaints were suspected to be possible dropouts. The third finding is that learners whose learning time intensity was mainly located in the later period had achievements that were significantly different from those of the regular periodical reading learners whose learning time intensity was distributed in all periods of the course. The above findings raise some issues and suggestions for those concerned with proposing asynchronous courses. As students can pace their own learning in an asynchronous learning environment, it is hard to avoid getting used to intermittent intensive reading. Instructors should consider seriously how to guide students to learn in a proper sequence through a well‐scheduled instructional programme. It is necessary to encourage students to exercise self‐discipline in regular on‐line reading for better learning outcomes.  相似文献   
94.
稀土钙钛矿催化剂制备方法的研究进展   总被引:12,自引:5,他引:12  
冉锐  吴晓东  翁端 《稀土》2004,25(5):46-50
稀土钙钛矿超微粉体的常规制备方法主要有机械混合法、化学共沉淀法、溶胶-凝胶法以及微乳液法等等。本文总结了以上各种方法的制备过程、特点以及在工艺优化方面国内外所取得的研究进展,并从机理上探讨了上述工艺对稀土钙钛矿催化剂相关性能的影响。  相似文献   
95.
水与可持续发展   总被引:3,自引:5,他引:3  
论述了水在可持续发展中的地位。当今存在的4大水问题,评估了未来的水形势,提出了解决水问题的途径。  相似文献   
96.
本文以行为导向型教学模式为切入点,探讨了这种开放式教学模式在德语二外教学中如何实现语言知识和文化意识的相互统一,以达到提高学员跨文化能力的教学目的。  相似文献   
97.
本文描述了教师和学生在网络教学中各自的活动和所扮演角色,并在此基础上探讨了教师如何更好地利用网络进行教学。  相似文献   
98.
互动式教学模式在实践中的运用   总被引:3,自引:0,他引:3  
论述了互动式教学模式依据的理论基础、涵义以及在课堂实践中的具体实施,旨在唤起和培养学生参与课堂活动意识,创造一种轻松、和谐、互补的教学环境,从而提高学生的语言应用能力。  相似文献   
99.
Although it is known that there are fundamental personality differences in the behavioral responses to emotional stimuli, traits have scarcely been investigated in this context by means of functional imaging studies. To maximize the variance with respect to personality, the authors tested 12 control subjects and 12 subjects who had sadomasochistic experiences with respect to the relationship between J. A. Gray's (1970) personality dimensions, the behavioral approach system (BAS) and the behavioral inhibition system (BIS), and brain activity in regions of interest. The BIS was associated with activity in numerous brain areas in response to fear, disgust, and erotic visual stimuli, whereas few associations could he detected between the BAS and brain activity in response to disgust and erotic stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
Recent studies have shown that both systemic and intra-nucleus accumbens (NAc) or intra-amygdala administration of dopamine D? receptor ligands modulate reward-related learning. A previous study (H. Aujla, H. Sokoloff, & R. J. Beninger. 2002) showed that systemic administration of the partial dopamine D? receptor agonist BP 897 selectively blocked the expression, but not the acquisition, of amphetamine-conditioned activity. This suggested the hypothesis that intra-NAc or intra-basolateral amygdala (BLA) BP 897 would attenuate the expression, but not the acquisition, of amphetamine-conditioned activity. Rats were habituated to activity-monitoring chambers for 5 days, for 1 hr each day. Conditioning occurred on the next 3 days, followed by a single 1-hr test session. Intra-NAc or intra-BLA infusions of BP 897 during test, but not during conditioning, attenuated intra-NAc amphetamine conditioned activity. Results indicate that the ability of BP 897 to attenuate the expression of conditioned activity is mediated in part by the NAc and BLA. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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