超临界600MW机组低压加热器疏水改造

超临界600MW机组^#7、^#8低压加热器存在疏水不畅的问题,主要原因是^#7、^#8低压加热器的汽侧压力之差较小,疏水水位差较大,疏水管线阻力大。在某公司进行的疏水改造中,通过减少疏水水位差、去掉疏水闸阀、优化管线布置等措施,减少了系统阻力。改造后,机组负荷在300MW时,实现了^#7、^#8低压加热器的正常疏水。     

基于神经网络的自密实混凝土间隙通过能力评价

为评价自密实混凝土间隙通过能力,首先以J形环装置对C40自密实混凝土间隙通过能力进行试验,再应用神经网络进行数值模拟,并对试验数据和模拟后的误差进行正交分析。结果表明,采用直径为300 mm的J形环,钢筋净距为最大粒径2.5倍时,是最优的,可以用来测试自密实混凝土的间隙通过性能。其评价指标为:H值为8 mm~12 mm,内外高差为5 mm~8 mm,扩展度为675 mm~700 mm。     

大采高工作面过断层围岩控制分析

以大采高工作面过断层围岩控制为对象开展探究。结合具体工程实际,在利用数值模拟手段分析围岩破坏特征的基础上,对围岩控制方式做出探究,并对其应用效果进行分析。结果表明,所设计方案实现了对围岩的有效控制,提升了工作面过断层的安全性。     

关于IGBT驱动电路的性能分析

分析了一个理想的IGBT驱动电路应具备的基本性能     

Integrated evolutionary neural network approach with distributed computing for congestion management

Electric supply industry is facing deregulation all over the world. Under deregulated power supply scenario, power transmission congestion has become more intensified and recurrent, as compared to conventional regulated power system. Congestion may lead to violation of voltage or transmission capacity limits, thus threatens the power system security and reliability. Also the growing congestion may lead to unanticipated divergent electricity pricing. Owing to these facts congestion management has become a crucial issue in the deregulated power system scenario.Fast and precise prediction of nodal congestion prices in real time deregulated/spot power market may enable market participants and system operators to keep pace with the congestion by taking preventive measures like transaction rescheduling, bids (both for supplying and consuming electricity) modification, regulated dispatch of electric power, etc. This paper proposes an integrated evolutionary neural network (ENN) approach to predict nodal congestion prices (NCPs) for congestion management in spot power market. Distributed computing is employed to tackle the heterogeneity of the data in the prediction of NCP values. Developed ENNs have been trained and tested under distributed computing environment, using a message passing paradigm. Proposed hybrid approach for NCP prediction is demonstrated on a 6-bus test power system with and without distributed computing. The proposed approach not only demonstrated the computing efficiency of the developed ENN model over the conventional optimal power flow method but also shows the time saving aspect of distributed computing.     

浅谈新车型涂装生产准备通过性分析

以奇瑞公司某涂装线为例,对新车型在该涂装线进行生产试制前的非标及机械化设备的通过性进行分析介绍。     

并行稀疏矩阵与向量乘的负载平衡和通信优化

本文考虑了在工作站机群上实现大型稀疏矩阵和向量乘的负载平衡。提出了一个快速负载平衡和有效的消息传递技术相结合的方法,来缓解计算和节点间通信。该方法的性能在工作站机群上进行测试,可获得良好结果;并且,通过I/O延迟隐藏和整体负载平衡使I/O开销能有效地分摊。     

AN ARGUMENT-BASED APPROACH TO NONMONOTONIC REASONING*

We define an argument system to be a pair consisting of a set of inference rules and a set of completeness conditions. Inference rules are used to build arguments. Completeness conditions are used to define argument structures, which are sets of arguments supporting belief sets. We reformulate Reiter's default logic as special argument systems. This enables us, among other things, to apply the negation-as-failure rule to general default theories. We also speculate on some other potential uses of our argument systems.     

PVM与网络并行计算

松散耦合的异构型并行处理系统近年来又有较大的发展，这种只能支持粗粒度并行的计算环境，由于通讯硬件的更新和软件环境的开发，其性能已经能够与某些ＭＰＰ机相媲美，因而形成并行处理领域一个强有力的分支－网络计算，本文围绕ＰＶＭ，讨论网络计算的软件环境，概述其特色和发展，并与其它基于消息传递的软件环境相比较，最后预测ＰＶＭ未来可能面临的问题和发展方向。     

一类IMBq方程的第二初边值问题

本文应用Galerkin方法和Leray-Schauder不动点原理,建立了一类IMAq方程的第二初边值问题解的存在唯一性。