支持MLS的多层次嵌入式高可信软件架构

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。     

知识流模型及其在航天企业中的应用

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。     

HFC－134a水平管内流动沸腾换热研究的进展

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．     

地理教育的现状与改革的思考

高考文科取消地理科目后，中学地理教育及高师地理教育均受到冲击，但地理科学的特殊地位决定了它是不可能被取代的．地理科学的发展应在应用方面找出路，并不断深化地理教育改革．     

现金流量表编制方法改进设想

根据《企业会计准则 -现金流量表》的要求 ,企业在编制现金流量表时应采用直接法报告经营活动现金流量 ,传统的直接法有工作底稿法和 T形帐户法 ,在这两种方法的操作中都要面对费脑筋的“调整分录”和“分析填列”,难度高、工作量大、自动化程度低 ,缺乏普及和实用性 ,而代码日记法则能克服这些缺陷 ,体现了简便易行的特点     

一种求解双目标flow shop排序问题的进化算法

提出一种求解双目标flow shop排序的递进多目标进化算法.算法采用改进的精英复制策略,在实现精英保留的前提下降低了计算复杂性;通过递进进化模式增加群体多样性,改善了算法收敛性;通过群体进化过程中对非劣解集进行竞争型可变邻域启发式搜索,增强了算法局部搜索性能.采用新算法和参照算法NSGA-II对31个标准双目标flow shop算例进行优化.研究结果表明,新算法在所有算例的求解中均获得了优于NSGA-II的非劣解集,验证了算法的有效性.     

Book Reviews

This article examines some difficulties associated with the Haynes–Stone model and attempts to clarify how the model can be justified as representing the hypothesis that “quantity is demand determined and price is supply determined.” It also argues that the applications of such a model as was done by Haynes and Stone might not have resolved the controversies related to the Phillips curve and the supply function of exports (or imports).     

休闲消费中的流体验生命周期探究

体验是随着消费者休闲消费的经验不断丰富而不断变化的，是一个动态的过程。体验如何变化以及休闲消费企业针对体验的动态过程的对策是需要解决的一个问题。利用流理论，从心理学角度探究休闲消费中的消费者体验主要有以下几点：首先，对心理学视角下的三个代表体验理论进行述评；其次，基于流体验理论提出休闲消费的流体验生命周期以及体验的总效用模型；最后，基于流体验生命周期从个人和休闲两个层面，提出提高消费者休闲消费倾向的对策。     

Correlates of perceived effectiveness of the Safe Schools/Healthy Students Initiative

A three-level growth-curve model was applied to estimate perceived impact growth trajectories, using multi-year data from project and school surveys on outcome and program implementation collected from 59 sites and approximately 1165 participating schools in the Safe Schools and Healthy Students Initiative. Primary interest is to determine whether and how project-level and school-level correlates affect schools’ perceptions of the Initiative's effectiveness over time when the effects of the pre-grant environmental conditions, grant operations, and near-term outcomes are considered. Coordination and service integration, comprehensive programs and activities for early childhood development, and change in school involvement were found to be significant predictors of school-perceived overall impact when the effect of poverty was considered. Partnership functioning, perceived importance of school resources, and school involvement were found to be significant predictors of school-perceived impact on substance use prevention when the effect of poverty was considered.     

Designing a multiple state repetitive group sampling plan based on the coefficient of variation

A multiple state repetitive group sampling (MSRGS) plan is developed on the basis of the coefficient of variation (CV) of the quality characteristic which follows a normal distribution with unknown mean and variance. The optimal plan parameters of the proposed plan are solved by a nonlinear optimization model, which satisfies the given producer's risk and consumer's risk at the same time and minimizes the average sample number required for inspection. The advantages of the proposed MSRGS plan over the existing sampling plans are discussed. Finally an example is given to illustrate the proposed plan.