基于超图模型的大规模门级网表层次化聚类算法

为了克服现有层次化方法通用性差、运算效率不高、电路结构提取不准等缺点,提出了一种基于超图模型的层次化聚类算法.首先对网表中最基本的迭代、总线、扇入和串联结构进行自动识别,然后将这4种基本结构按不同的组合方式进行多级聚类,最终建立起了网表的层次化结构.由于文中基本结构聚类算法是专门针对超图数据结构设计的,其时间复杂度较低.实验结果表明,该算法既可以得到较准确的层次信息,又能保证较高的运算速度,对各种应用均有较好的效果.     

LabVIEW在数字电路教学中的应用

根据LabVIEW的功能特点,提出了用LabVIEW对数字电路进行仿真教学.本文以74148集成8线-3线优先编码器为例分析了LabVIEW在数字电路教学中的应用,并完成了4线-2线、8线-3线、10线-4线普通编码器和优先编码器的设计,将各个编码器程序集成在一个主程序面板中,用数字显示的方式将结果显示出来.通过仿真验证其结果与实际元器件的功能完全相同,这样既丰富了教学方法和手段,又提高了教学质量,增强了学生学习的兴趣和积极性.     

闭环驱动微陀螺电路建模与仿真

微机械陀螺以抗;中击强度高、功耗低等优点在军事、民用方面都有着巨大的应用潜力,是各国研究机构和公司研究的一个重点方向。系统建模与仿真可以验证陀螺接口电路方案的可行性,指导具体模块电路的实现,实现结构与电路的协同优化设计。本文从陀螺接口电路的工作原理出发,对其进行数学语言描述,最终实现它的Simulink建模与仿真,从而验证电路方案设计的可行性,为后续工作奠定基础。     

Oriented energy,nearness and fault diagnosis

This paper describes why the k-dimension maximal oriented energy subspace of the measurable voltage-change matrix id the optimal feature to locate faults in a population of circuits. The paper elaborately designs a "nearness" concept, which is used to construct a fault candidate set in a small size, and proposes a maximal nearness criterion. On the basis of these, the paper presents a novel algorithm to efficiently improve the accuracy and speed of fault locating.     

PI k mass production and an optimal circuit for the Nečiporuk slice

Letf: {0,1} ⁿ {0,1} ^m be anm-output Boolean function inn variables.f is called ak-slice iff(x) equals the all-zero vector for allx with Hamming weight less thank andf(x) equals the all-one vector for allx with Hamming weight more thank. Wegener showed that PI _k -set circuits (set circuits over prime implicants of lengthk) are at the heart of any optimum Boolean circuit for ak-slicef. We prove that, in PI _k -set circuits, savings are possible for the mass production of anyFX, i.e., any collectionF ofm output-sets given any collectionX ofn input-sets, if their PI _k -set complexity satisfiesSC _m (FX)3n+2m. This PI _k mass production, which can be used in monotone circuits for slice functions, is then exploited in different ways to obtain a monotone circuit of complexity 3n+o(n) for the Neiporuk slice, thus disproving a conjecture by Wegener that this slice has monotone complexity (n ^3/2). Finally, the new circuit for the Neiporuk slice is proven to be asymptotically optimal, not only with respect to monotone complexity, but also with respect to combinational complexity.     

大型同步调相机转子故障温度场分析

随着特高压交直流输电的发展,同步调相机以其快速动态响应能力重新受到关注,同步调相机的安全运行关乎电网的稳定性。论文以TTS-300-2型双水内冷同步调相机为研究对象,建立了其转子三维模型,计算并分析了转子不同负荷下、同一位置不同水路堵塞程度时的转子三维温度场,转子匝间短路和水路堵塞同时存在时的温度场以及转子水路堵塞时的热应力情况,评估故障产生的影响和同步调相机带病运行能力。结果表明,不同负荷下转子温度场分布相似;转子出现故障会导致温度分布不平衡;单个槽内堵塞匝越多,转子温度场畸变越明显;且随堵塞程度的增加,转子热应力随之增加。     

A fully differential transimpedance amplifier with integrated differential photodetector in standard CMOS process for optical communications and interconnects

A fully differential transimpedance amplifier (TIA) with integrated differential photodetector in standard CMOS technologies has been realized for optical receivers in optical communications and optical interconnects. And a novel, fully differential photodetector aiming to convert the incident light into a pair of fully differential photo-generated currents and ensure the differential symmetry on circuit configuration and model has also been proposed for the differential TIA to achieve the fully differentia...     

面向分组密码的NCL电路处理模型

根据分组密码操作方式的特点,提出一种面向分组密码处理的NCL电路模型。采用双异步流水线并行工作方式、线性握手和非线性握手混合的握手方式以及基于NCL闭环流水线的控制方式,将AES算法在该模型上进行映射,使用异步电路综合工具Balsa在1 µm工艺下进行综合和仿真,结果证明该模型有效。     

A bandpass filter with adjustable bandwidth and predictable transmission zeros

In this article, a microstrip bandpass filter with an adjustable bandwidth and predictable transmission zeros is proposed. The proposed filter is implemented by combining two hairpin edge‐coupled resonators with interdigital capacitors. Compared to typical edge‐coupled filters, the proposed filter provides a wider bandwidth resulting from a higher coupling strength between its resonators. To further increase the coupling and consequently the bandwidth, a pair of etched slots in the ground plane is used. By adjusting the geometrical parameters of the interdigital capacitors and etched slots, the bandwidth can be easily adjusted. The filter features two transmission zeros, which are determined by means of the semi‐analytical model developed as part of this work. Furthermore, the proposed filters can be cascaded to obtain a sharper cutoff frequency response. Frequency responses of the filters from measurements are in good agreement with those simulated using IE3D in the 5–9 GHz range. © 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010.     

Joint stiffness identification of six-revolute industrial serial robots

Although robots tend to be as competitive as CNC machines for some operations, they are not yet widely used for machining operations. This may be due to the lack of certain technical information that is required for satisfactory machining operation. For instance, it is very difficult to get information about the stiffness of industrial robots from robot manufacturers. As a consequence, this paper introduces a robust and fast procedure that can be used to identify the joint stiffness values of any six-revolute serial robot. This procedure aims to evaluate joint stiffness values considering both translational and rotational displacements of the robot end-effector for a given applied wrench (force and torque). In this paper, the links of the robot are assumed to be much stiffer than its actuated joints. The robustness of the identification method and the sensitivity of the results to measurement errors and the number of experimental tests are also analyzed. Finally, the actual Cartesian stiffness matrix of the robot is obtained from the joint stiffness values and can be used for motion planning and to optimize machining operations.