Statistical analysis of large on-chip power grid networks by variational reduction scheme

One of the most critical challenges in today's CMOS VLSI design is the lack of predictability in chip performance at design stage. One of the process variabilities comes from the voltage drop variations in on-chip power distribution networks. In this paper, we present a novel analysis approach for computing voltage drops of large power grid networks under process variations. The new algorithm is very efficient and scalable for huge networks with a large number of variational variables. This approach, called variational extended truncated balanced realization (varETBR), is based on model order reduction techniques to reduce the circuit matrices before the variational simulation. It performs the parameterized reduction on the original system using variation-bearing subspaces. After the reduction, Monte Carlo based statistical simulation is performed on the reduced system and the statistical responses of the original system are obtained thereafter. varETBR calculates variational response Grammians by Monte Carlo based numerical integration considering both system and input source variations in generating the projection subspace. varETBR is very scalable for the number of variables and flexible for different variational distributions and ranges as demonstrated in experimental results. Experimental results, on a number of IBM benchmark circuits up to 1.6 million nodes, show that the varETBR can be 1900X faster than the Monte Carlo method and is much more scalable than one of the recently proposed approaches.     

CFRE 采办模式在降低工程成本中的作用

简要介绍平湖油气田开发项目设备采办的“实报实销”(CFRE)模式，和运用这种采办模式降低工程成本的几点体会。     

利用VFP编程实现Excel表数据转移

基于实现生成降水量合理性对照表的目的，对程序设计思想和实现方法做简要介绍。主要是利用VFP编程语言自动实现EXCEL表格内数据批量转移至另一个EXCEL表内，而省去繁琐的人工劳动，并减少手工操作过程中出错的可能性。     

Minimal representations of continuous-time processes having spectral density with zeros in the extended imaginary axis

Given a process y with stationary increments and rational incremental spectral density Φ(s), we parametrize minimal state-space representations of dy. We consider the case when Φ(s) may have zeros on the imaginary axis including infinity and we analyze the zero structure of each state-space representation.     

我国新型城镇化的发展维度与实现路径

分析我国的城镇化进程中存在的政府角色错位、内在驱动力不足、人的城镇化严重不足、布局亟待优化调整等问题;然后指出推进城镇化需要关注产业经济发展、城镇文化建设与制度创新等三个发展维度;最后提出我国社会的城镇化的实现路径,包括培育与发展民营经济、创新政府职能、妥善解决"三农问题"问题。     

大动态范围PGA电路的设计与实现

本文通过理论分析与实验研究,介绍了一个大动态范围ＰＧＡ电路的设计与实现过程,并从理论和实践上证明：大动态范围ＰＧＡ电路是压缩大动态模拟信号动态范围并可提高信号检测精度的一种行之有效的技术方案。     

基于ERA的统计能量分析参数确定方法

统计能量分析（SEA）是解决复杂结构高频动力学问题的有效方法,正确估计统计能量分析参数则是利用该方法得到可靠分析结果的关键。论文基于特征系统实现算法(ERA)提出一种确定统计能量分析参数的方法,首先应用ERA辨识统计能量分析系统的最小阶功率流模型,然后利用辨识模型的特征对修正初始统计能量分析模型,进而得到较精确、可靠的参数。三子系统SEA模型的仿真结果验证了利用该方法得到的统计能量分析参数的正确性,而且在一定测量噪声干扰下仍能保持较好的精度。最后,对铝蜂窝夹层结构小卫星的SEA模型进行了仿真,进一步验证了算法可应用于复杂结构的统计能量分析参数识别。     

DCS集散控制系统在制氧系统中的应用

4#20000制氧机采用了美国ABB公司的Industrial IT集散控制系统,本文主要介绍该系统的硬件配置、软件开发以及系统实现的功能,该系统在最大程度上满足了生产的需要。     

Controller reduction via frequency weightings considering $H_{\infty}$ property preservation

In this paper, a new controller reduction method is proposed to preserve the property using frequency weightings. It is necessary to consider decreasing degradation of property for controller reduction. It is well known that all controllers are represented by free parameters which are stable and bounded. In the paper, frequency weightings are given to stabilize the free parameters, and low‐order controller is provided by using frequency‐weighted balanced technique. Some numerical examples are given to show the effectiveness of the method. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(2): 63–69, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20683     

一种改进的定点FFT溢出处理方法

针对定点快速傅里叶变换（FFT）在运算准确度与实现复杂度方面不能兼顾的问题,对定点FFT算法的溢出检测方法进行了研究,并在Welch方法的基础上,提出了新的溢出检测方法.在所提方法中,将溢出检测模块放在每个蝶形运算开始的位置,对将要参加本次运算的输入数据进行溢出检测,且每个蝶形中只需一次检测.与Welch的方法相比,所提方法误差小,仿真结果表明,当平均误差（均方根误差与运算结果均方根的比值）或信号量化噪声比相同时,所提方法可节约一定的比特数.