开放式数控切割机神经网络误差补偿研究

分析了影响数控火焰切割机加工精度的主要因素,利用开放式数控系统的软件开放性,提出了采用IGCAQBP学习算法的神经网络方法来对包括金属热变形、机械传动误差等非线性因素在内的多种因素造成的加工误差进行误差补偿,设计了嵌入开放式数控系统中的神经网络误差补偿器,给出了实用的补偿器使用方法,并对误差补偿功能进行了扩展,仿真结果和实际应用表明该方法稳定有效。     

完善公司治理，构建良好的内部控制环境

内部控制是解决当前我国一些企业内部管理松弛、制度弱化、会计信息失真以及从源头上治理腐败的重要手段之一。公司治理结构为内部控制提供了外部环境,内部控制为公司治理的有效运作和实施提供了制度保障,只有通过建立完善的公司治理结构,达到公司与所有利害相关者之间利益关系的制衡与协调,才能保证公司决策的科学化,最终维护公司各方面的利益,进而保证内部控制体系的建立及作用的有效发挥。     

现代教育技术对培养创新人才的作用

现代教育技术对创新人才的创新精神和创新能力两大核心要素的培养上,尤其是对创造性思维能力的培养具有无可比拟的独特作用。具有智能模拟功能的教育技术能够促进学习者对知识的自主建构,有力激发学习者的创造动机和创造灵感。协作式学习、多媒体课件以及教师指导的相互配合,能够促进学习者求异发散思维、直觉形象思维和抽象逻辑思维的整全发展,从而提升创新能力。     

Empirical Non-Parametric Control Charts: Estimation Effects and Corrections

Owing to the extreme quantiles involved, standard control charts are very sensitive to the effects of parameter estimation and non-normality. More general parametric charts have been devised to deal with the latter complication and corrections have been derived to compensate for the estimation step, both under normal and parametric models. The resulting procedures offer a satisfactory solution over a broad range of underlying distributions. However, situations do occur where even such a large model is inadequate and nothing remains but to consider non- parametric charts. In principle, these form ideal solutions, but the problem is that huge sample sizes are required for the estimation step. Otherwise the resulting stochastic error is so large that the chart is very unstable, a disadvantage that seems to outweigh the advantage of avoiding the model error from the parametric case. Here we analyse under what conditions non-parametric charts actually become feasible alternatives for their parametric counterparts. In particular, corrected versions are suggested for which a possible change point is reached at sample sizes that are markedly less huge (but still larger than the customary range). These corrections serve to control the behaviour during in-control (markedly wrong outcomes of the estimates only occur sufficiently rarely). The price for this protection will clearly be some loss of detection power during out-of-control. A change point comes in view as soon as this loss can be made sufficiently small.     

浅评海德格尔的技术观

文章对海德格尔关于现代技术的根源、本质及技术与人类的历史命运的关系进行评价,指出了人类要全面审视技术,注意合理地运用技术,以克服技术给人类带来的消极后果,将技术的发展纳入人类稳定而长远发展的规程,从而掌握人类的命运.     

从中国信息化实践看信息技术观的社会形成

中国信息化的技术实践中,不仅能够呈现出技术观的现代性特征,而且还能够反映出后现代特征。通过对中国信息技术观的技术理性和人文理性因素等分析,可以发现信息技术观的形成乃是一个复杂的、与社会相互作用过程的结果。围绕着信息技术发展和技术观的社会形成问题的讨论,具有多方面的社会意义。     

2001—2002赛季CBA与NBA技术统计的比较与分析

对 2 0 0 1— 2 0 0 2赛季CBA与NBA各项技术进行了统计比较与分析 ,建议CBA在应有的基础上继续努力 ,提高球员的身体素质和技术能力 .     

工程建设项目投资控制

论述投资控制的关键环节,提出投资控制工作的实施要点,阐明投资控制工作的必要性、可行性和重大意义.     

Some remarks on the physical models concerning two different approaches to inference in statistical process control

Summary For technological applications it can be useful to identify some simple physical mechanisms, which, on the basis of the available knowledge of the production process, may suggest the most appropriate approach to statistical control of the random quantities of interest. For this purpose the notion of rupture point is introduced firstly. A rupture point is characterized bym randomly arising out of control states, assumed to be mutually exclusive and stochastically independent. Shewhart's control charts seem to represent the natural statistical tool for controlling a rupture point; however it is shown that they are fully justified only when the hazard rates attached to the causes of failure are constant. Otherwise, typically in the presence of time increasing hazard rates, Shewhart's control charts should be completed by a preventive intervention rule (preventive maintenance). In the second place, the notion of dynamic instability point is introduced, which is specifically characterized by assuming that the random quantity of interest is ruled by a stochastic differential equation with constant coefficients. By discretization, developed according to a possibly new approach, it is shown that the former model reduces to an equation error model, which is among the simplest used in adaptive control, and thus particularly easy to deal with in regard to parameter estimation and the definition of the optimum control rule.     

具有反馈控制的Logistic扩散系统周期解的存在与稳定

利用上下解，Ｂｒｏｕｗｅｒ不动点原理及Ｌｙａｐｕｎｏｖ泛函方法，讨论了一类具有反馈控制的Ｌｏｇｉｓｔｉｃ扩散系统的周期解问题；获得了周期解存在且稳定的判别条件．