A technique for uncertainty reduction based on order commonality

The use of commonality is widely diffused as a criterion to reduce uncertainty in demand forecasts for the master production schedule (MPS). Nevertheless, studies have mostly focused on exploiting component commonality in make to stock and assemble to order manufacturing. This paper refers to planning environments with two specific characteristics. First, the degree of certainty of the demand is extremely low, due to product complexity, with poor modularization and standardization, and to the presence of few customers of large dimensions. Second, the delivery lead time is less than the total lead time. In this situation, demand for MPS planning units is extremely uncertain and sporadic. It is therefore necessary to formulate in advance forecasts of customer orders with a redundant configuration. In this paper a technique for the reduction of demand uncertainty is introduced, based on the exploitation of order commonalities. In particular, relations between order commonality and uncertainty reduction in a planning environment with such complex features are illustrated. Then, guidelines for the implementation of the technique in order to reduce over-planning in the master production schedule are provided. Finally, the performances of the technique are empirically analysed by means of both a simulation model and experimental application in a telecommunication systems manufacturer     

关于上海新一轮改革的若干思考

当前是上海加快推进“四个率先”、加快建设“四个中心”和社会主义现代化国际大都市的关键时期，国内外发展的新形势对改革的重点、方式、任务、动力以及实施路径提出了新的要求，上海必须根据当前改革发展的阶段特征，按照顶层设计的改革推进思路，着力围绕转型发展的目标要求，重点在民生改善、服务经济、内外开放、政府改革和改革机制完善等方面实现关键性突破，以带动上海改革的整体推进和持续深化。     

“国防一线”的“三线建设”——云南三线建设的历史研究

云南处于援越抗美和对越自卫反击战的国防一线，同时又是我国地缘国防战略的大后方。既是“一线”又是“三线”的特殊地缘政治环境，赋予了云南三线建设独特的面貌和经验。在1964年至1980年的云南三线建设历程中，经历了两个建设高潮。文章试图真实再现各个阶段的规划部署、实施过程，分析出现的问题，以弥补相关研究的不足。这场特殊的“备战经济”建设，为保卫边疆安全、巩固国防发挥了应有的作用，同时也为云南的经济社会发展做出了重大的贡献。     

计算机课堂“任务驱动”教学模式探索

“任务驱动”教学模式是一种适用于培养学生自学能力和独立分析问题能力的教学方法，在计算机学科教学中运用最广泛．本文就“任务驱动”教学模式的定义、作用及如何才能科学合理设计课堂任务等问题进行了讨论．     

高校教务管理浅论

高等学校教务管理工作运行的好坏,直接影响到教学质量的优劣,因而必须加强教务管理工作.加强教务管理,首先要有明确的工作目标,其次要加强教学管理队伍建设,努力提高队伍素质,再次是要做到严格管理计划,加强制度管理.     

对体育竞赛有关数学应用题的初步探讨

本文归纳总结了体育竞赛有关的数学问题，为体育训练工作者更合理，更科学地分析和掌握运动员的比赛成绩和训练数据提供帮助。     

党的基本路线是党和国家的生命线——论把一个中心和两个基本点统一于发展中国特色社会主义的伟大实践,要牢牢把握"统一"和"实践"两个关键词

一个中心、两个基本点,是党在现阶段基本路线的主要内容。十七大报告强调"党的基本路线是党和国家的生命线",指出要坚持把一个中心和两个基本点"统一于发展中国特色社会主义的伟大实践,任何时候都决不能动摇"。理解这一论断,要牢牢把握两个关键词:一是"统一",即从理论认识上搞清楚一个中心与两个基本点之间以及两个基本点相互之间有机统一的辩证关系。二是"实践",即不能停留在理论认识上或口号上,而要落实在行动中和实践中,为此必须做到制定具体的工作路线和政策,应符合这种"统一"的要求;善于及时总结经验,敢于坚持真理修正错误;正确把握舆论导向,防止"左"和右的干扰。     

谈高校宣传思想工作的创新

学校发展无止境，宣传思想工作创新就无止境。高校宣传思想工作要牢牢把握“八点”，即：研究深点、突出特点、抓住重点、关注热点、工作细点、行动快点、效果好点、勤奋学点，不断创新，促进学校各项建设事业的发展。     

Ad hoc网络中基于拥塞的机会调度算法

无线多跳Ad hoc网络中的节点在业务发送过程中需要竞争共享信道,容易发生局部拥塞导致网络性能下降,而且节点内部采用的先入先出(FIFO)队列容易使队头出现阻塞现象,影响队列中后续分组的发送。为此提出了一种基于拥塞的机会调度算法,发送节点发送RTS帧时目标指向多个下一跳接收节点,这些节点在正确解码RTS帧后根据自身拥塞程度按一定概率依照调度优先级顺序发送CTS帧。仿真结果表明,该算法提高了网络端到端的饱和吞吐量和信道利用率,也提高了业务流之间的公平性。     

A proposed methodology for the prediction of mental workload, based on engineering system parameters

In the design of engineering systems, mental workload is one of the most important factors in the allocation of cognitive tasks. Current methods of task allocation have criteria that are defined in only general terms and are thus not very useful in aiding detailed decision-making in system design. Whilst there are many quantitative criteria available to determine the physical space in human-machine interaction, system designers really require an explicit model and specific criteria for the following identification of the mental workload imposed by the system; prediction of both human and system performance; evaluation of the alternatives of system design; and the design of system components. It is argued that the available methods of workload or performance are either too domain-dependent to apply to the design of other systems, or subject-dependent and thus do not reflect the objective workload imposed by the system. The presented research adopts a new approach to cognitive task analysis in dynamic decision-making systems. Based on the characteristics derived from task analysis, a general conceptual model of the prediction of mental workload in system design is proposed. In the new model, workload is represented by a set of system parameters—task arrival rate, task complexity, task uncertainty, and performance requirements—which are considered to be the main sources of workload. In this context, workload becomes an objective demand of engineering systems, independent of any subjective factors. Whether an individual or population is overloaded depends upon their workload threshold with respect to the specified task and environment. It is hoped that this new model, after both laboratory and industrial validation, could be used by system designers to predict the workload imposed on people by systems.