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81.
英语网语成因复杂,既受社会因素、心理因素、黑客因素影响,又同人类认知及语言自身发展规律密不可分。深层次探析该语言现象的理据,为研究汉语网语及未来语言的发展趋势提供参考。  相似文献   
82.
The manufacturing industry is currently facing unprecedented challenges from changes and disturbances. The sources of these changes and disturbances are of different scope and magnitude. They can be of a commercial nature, or linked to fast product development and design, or purely operational (e.g. rush order, machine breakdown, material shortage etc.). In order to meet these requirements it is increasingly important that a production operation be flexible and is able to adapt to new and more suitable ways of operating. This paper focuses on a new strategy for enabling manufacturing control systems to adapt to changing conditions both in terms of product variation and production system upgrades. The approach proposed is based on two key concepts: (1) An autonomous and distributed approach to manufacturing control based on multi-agent methods in which so called operational agents represent the key physical and logical elements in the production environment to be controlled – for example, products and machines and the control strategies that drive them and (2) An adaptation mechanism based around the evolutionary concept of replicator dynamics which updates the behaviour of newly formed operational agents based on historical performance records in order to be better suited to the production environment. An application of this approach for route selection of similar products in manufacturing flow shops is developed and is illustrated in this paper using an example based on the control of an automobile paint shop.  相似文献   
83.
ABSTRACT

Annual net cash returns and net capital gains provide farmers with their actual and potential monetary rewards, respectively. This article reports on a national farm survey showing both actual and potential returns, on average, are not as high as might be imagined. This is supported by the findings of earlier studies and has implications for rural societies and their associated economies. Data on income, expenses and profit is presented as is data on farm value changes over the life of each farm. The information is adjusted for inflation to provide ‘real’ data. The profit and net capital gain figures are divided into groupings based on a range of criteria such as total farm capital, and labour compliment as a reflection of farm size. Statistically significant differences occur for some groupings such as farm type and farm size.  相似文献   
84.
Traceability is normally difficult to achieve in continuous processes, since there are no natural batch structures. In this article, we demonstrate flow-based simulation using process data to improve traceability in a continuous pelletising process. Using the simulation model, the engineers could test the impacts of process disturbances, identify cause and effect relations and aid control in case of process disturbances. In a field trial where the chemistry of an additive was varied during production of a special product, the simulation forecasts predicted the level of the chemical content after the plant within the errors that the engineers found acceptable.  相似文献   
85.
通过分析实际供水管网系统的特征,对管网工况分析所涉及的几个尚未解决的计算问题进行了研究,提出了用计算机进行工况分析的思路与框架,为管网运行调度及研究管网水质模型打下了良好基础.  相似文献   
86.
为增强安全关键系统的高可信能力,在分析高可信保障机制现状的基础上,提出了一种多层次的高可信软件架构。该架构采用时空分离思想、虚拟机技术,为基于MLS的嵌入式安全关键系统提供了一种整体解决方案。基于该架构,研究了多层次的安全和防危策略管理方法、信息流控制机制、可信软件的评估和认证方法,为安全关键嵌入式系统提供可认证的安全服务。  相似文献   
87.
知识流模型及其在航天企业中的应用   总被引:16,自引:0,他引:16  
知识管理的理论和实践吸引了众多学者和企业家的关注,但在具体的实施方法上一直没有形成共识。管理的对象是“知识”,对于知识流动的理解、监测乃至控制是顺利实施知识管理项目的基础。已有的研究对知识流的讨论集中于描述概念,或通过统计分析或调查问卷得到对专利、引用等知识流动的描述。把Petri网理论用在对知识流进行刻画中,提出知识流的Petri网模型,能够描述知识分布的拓扑结构、知识存量、一定时期的知识流量和流速,使得管理人员便于监控和管理知识流动,更好地实施知识管理。把基于Petri网的知识流模型应用于航天企业中,通过实证分析说明该知识流模型对知识流动的刻画能力,并通过对现状的分析,为改进知识流动效率,实现知识管理目标提供支持。  相似文献   
88.
大学英语教学与综合能力培养   总被引:1,自引:0,他引:1  
本文根据修订后的<大学英语教学大纲>,倡导在教学实践中运用现代外语教学理论,推行以学生为主体以实践为中心的教学模式,打好大学生英语语言基础,提高大学生运用英语语言的综合能力.  相似文献   
89.
在分析国外有关文献的基础上,对HFC-134a水平管内流动沸腾换热研究的现状和已取得的成果进行了综述,指出了该领域进一步研究的方向.  相似文献   
90.
This paper evaluates the impact of a recent Norwegian family-policy reform. The reform provides benefits of up to NOK 3,000 (approximately € 400) per month to families with one- to three-year-old children, who do not utilize state-subsidized day-care centres. We investigate the reforms effect on parents labour force participation. We find that, on average, the reform reduced womens labour force participation and increased the specialization of work between couples. We find that the effect of the reform depends on womens schooling. Specifically, the labour force participation of highly educated mothers fell by more than that of mothers with less education.I am grateful to Associate Professor Espen Bratberg and Professor Alf Erling for their valuable comments. My special thanks to Kjell Vaage, Arild Aakvik and Afsane Bjorvatn for helpful suggestions. This paper was presented in a seminar at the Department of Economics, University of Bergen, Norway. I am thankful to the participants of the seminar for their positive feedback. The paper has also benefited from the reports given by three anonymous referees. I am also thankful to Professor Heather Joshi for helpful remarks on the paper. Responsible editor: Christoph M. Schmidt.  相似文献   
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