一种优化的AP-CAPSA中文文本结构分析算法*

从段落向量空间模型、特征词权重等多个侧面分析比较了已有的文本结构分析算法,提出了优化的AP-CAPSA算法;给出了算法性能的评价准则,并在不同的语料集合上进行了测试。实验表明该方法能够更有效地反映文本的结构,为中文自动摘要系统奠定了重要的理论基础。     

基于PLC的工业发酵自动控制解决方案

介绍了工业发酵自动化系统的构成，详细讲解了PLC在啤酒发酵罐区监控系统中，数据采集和对现场执行机构动作监控方面的应用。     

Numerical evaluation of the effects of friction and geometric nonlinearities on the energy release rate in three- and four-point bend end-notched flexure tests

Nonlinear finite element analyses are used to examine the effects of friction and geometric nonlinearities on the energy release rate in three- and four-point bend end-notched flexure tests. Energy release rates are first determined by a recently developed direct energy balance approach. It is shown that the finite diameter loading rollers that are typically used in practical test set-ups cause both tests to be inherently nonlinear. The effect of these nonlinearities on the energy release rate is shown to be larger in the four point than the three point test and to increase with increasing roller diameter, increasing coefficient of friction along the crack plane, and decreasing supporting span length. For the four point test, the effect of these nonlinearities is also shown to increase with increasing ratio of inner to outer span length. Next, energy release rates at the onset of crack advance are determined by a simulated compliance calibration technique. This “perceived toughness” is compared with predictions of the “true toughness” given by the direct energy balance approach at the same load. It is shown that perceived toughnesses from this simulated compliance calibration procedure are larger than previously reported results that were obtained in a similar fashion using linear theory. In addition, the perceived toughness is shown to strongly depend upon the range used for fitting the load versus deflection data to obtain compliance. These findings are used to make some general recommendations regarding use of the two test methods and their associated data reduction techniques.     

基于电流实部与虚部双向追踪的输电设备利用份额模型及应用

:针对输电设备利用份额的传统定义不能计及有功和无功潮流的耦合作用,基于电流的实部与虚部分量提出输电设备利用份额的新模型及定义。该模型将节点和支路功率转换为电流,通过对电流的实部和虚部分别进行双向追踪,可得到全网用户对输电网的利用份额。该模型不受分配模式的限制,通过恰当处理对地支路,可直接用于联营体模式下输电损耗和成本的完全分摊,文中给出了相关证明。采用“节点分裂”的等效方法和面向元件的分配模式,该方法可实现联营-双边交易共存模式下输电损耗的分摊。以5节点系统为例,对新定义和几种不同定义进行了比较,并对双边交易的增量和边际损耗及本文结果进行了分析。给出的IEEE-30节点算例验证了该方法的有效性。     

零电压零电流开关全桥PWM变换器的研究

文本通过分析全桥ZVZCS PWM变换器的工作原理,得出其与传统的全桥ZVZCS PWM变换器的不同之处,然后具体分析对于变化的负载电流,电路环流是如何自我调节以实现ZCS的,并给出了一些影响实现ZVZCS的关键元器件的参数设计公式。最后样机的试验波形证了本文的分析研究。     

Quantum-mechanical effects and gate leakage current of nanoscale n-type FinFETs: A 2d simulation study

This paper simulates a kind of new sub-50 nm n-type double gate MOS nanotransistors by solving coupled Poisson-Schrödinger equations in a self-consistent manner with a finite element method, and presents a systematic simulation-based study on quantum-mechanical effects, gate leakage current of FinFETs. The simulation results indicate that the deviation from the classical model becomes more important as the gate oxide, gate length and Fin channel width becomes thinner and the Fin channel doping increases. Gate tunneling current density reduces with the body thickness decreasing. Excessive scaling increases the gate current below Fin thickness of 5 nm. The gate current can be dramatically reduced beyond 10¹⁷ cm⁻³ with the Fin body doping increasing. In order to understand the influence of electron confinement, quantum mechanical simulation results are also compared with the results from the classical approach. Our simulation results indicate that quantum mechanical simulation is essential for the realistic optimization of the FinFET structure.     

基于规则和统计的中文自动文摘系统

自动文摘是自然语言处理领域里一个重要课题,本文在传统方法基础上提出了一种中文自动文摘的方法。在篇章结构分析里,我们提出了基于连续段落相似度的主题划分算法,使生成的文摘更具内容全面性与结构平衡性。同时结合了若干规则对生成的文摘初稿进行可读性加工处理,使最终生成的文摘更具可读性。最后提出了一种新的文摘评价方法(F-new-measure)对系统进行测试。系统测试表明该方法在不同文摘压缩率时,评价值均较为稳定。     

铝电解槽热平衡测试计算中的几点问题

由于缺乏正规的标准，铝电解槽能量平衡测试中存在着一些概念混淆、计算方法和公式错误的情况，应引起测试工作者的注意，在测试计算前应认真制订方案，多查一些参考资料，核实所用公式、数据，避免发生失误。同时对于类似计算，由于计算机的应用，应尽可能采取精确算法。没必要采取一些非常粗糙的近似算法和经验值。     

西藏自治区藏中电网光纤通信网的建设及发展

西藏自治区由于受地理环境等多方面因素的制约，长期以来各地区级的电网均独立运行，造成通信网发展相对滞后。但近几年随着电业大发展，地区电网相互连接共同进行，促进了通信网的快速发展。文章详细介绍了藏中电网光纤通信网的发展现状，包括网络拓扑结构、SDH和PCM设备、光纤线路的建设情况以及现存的问题，并阐述了今后的发展规划。     

一种晶闸管整流器全关断检测电路

本文提出并介绍了欧姆逻辑无环流检测的一种方案——晶闸管流器全关断检测，并与软件检测和电流互联器检测进行比较分析，最终得出晶闸管全关断检测方案准确可行的结论。全关断的输出信号与上述两种信号进行综合利用，从而准确可靠地实现了欧姆的逻辑无环流控制。