一种自动布线方法：多级线探索法

本文介绍了一种在微机上实现的印制板自动布线方法──多级线探索法及其编程方法。这种方法是基于完备布线算法的概念，通过分析李氏算法和传统线探索法的不足之处而得到的。虽然它也是一种线探索法，但有较传统线探索法更强的探索能力，不需要结合李氏算法而能单独完成布线任务，是一种较理想的算法，通过实验获得了较为满意的效果。     

Finding nondegenerate Hopf bifurcation points for four-dimensional two-parametric systems

We establish a numerically feasible algorithm to find a simplicial approximation A to a certain part of the boundary of the set of stable (or Hurwitz) polynomials of degree 4. Moreover, we have that . Using this, we build an algorithm to find a piecewise-linear approximation to the intersection curve of a given surface contained in ⁴ with . We have also devised an efficient computer program to perform all these operations. The main motivation is to find the curve of nondegenerate bifurcation points in parameter space for a given 2-parametric Hopf bifurcation problem of dimension 4.     

Unscented Kalman filtering in the additive noise case

The unscented Kalman filter(UKF) has four implementations in the additive noise case,according to whether the state is augmented with noise vectors and whether a new set of sigma points is redrawn from the predicted state(which is so-called resampling) for the observation prediction.This paper concerns the differences of performances for those implementations,such as accuracy,adaptability,computational complexity,etc.The conditionally equivalent relationships between the augmented and non-augmented unscente...     

地下管线探测各阶段应重视的要点

主要分析了在地下管线探测各阶段应重视的要点以及相应的处理等问题。     

彩电合格焊点及其激光检测

激光／红外印制电路板焊点检测系统，是８０年代中期出现的世界上最先进的焊点质量检测手段，其检测速度、检测精度、检测可靠性和重复性、自动化程度，都是人工目视等其它方法远远不可比拟的。笔者对大量试验结果进行分析，可以认为：焊点激光红外检测数据、润湿角大小、焊点外形及抗拉强度数值、焊料重量值和合金层，可以作为判断焊点合格与否的标准。     

On the extreme eigenvalues of Toeplitz and real Hankel interval matrices

The purpose of this paper is to evaluate the extreme eigenvalues of a Hermitian Toeplitz interval matrix and a real Hankel interval matrix. A (n×n)-dimensional Hermitian Toeplitz (HT) matrix is determined by the elements of its first row, sayr. If the elements ofr lie in complex intervals (i.e., rectangles of the complex plane), we call the resulting set of matrices an HT interval (HTI) matrix. An HTI matrix can model real world HT matrices where the elements of the vectorr have finite precision (e.g., because of quantization, or imprecise measurement devices). In this paper we prove that the extreme eigenvalues of a given HTI matrix can be easily obtained from the 2^2(n–1) vertex HT matrices where the first element ofr is set to zero. Similarly, as a special case we obtain that the extreme eigenvalues of a real symmetric Toeplitz interval (RSTI) matrix can be obtained from 2 ^n–1 vertex matrices. Based on the above results we provide boxlike bounds for the eigenvalues on non-Hermitian complex and real Toeplitz interval matrices. Finally, we consider a real Hankel interval matrix. We prove that the maximal eigenvalue of a (n×n)-dimensional real Hankel interval matrix can be obtained from a subset of the vertex Hankel matrices containing 2^2n–3 vertex matrices, whereas the minimal eigenvalue can be obtained from another such subset also containing 2^2n–3 vertex matrices.     

On Curvatures and Focal Points of Distributions of Dynamical Lagrangian Distributions and their Reductions by First Integrals

Pairs (Hamiltonian system, Lagrangian distribution) called dynamical Lagrangian distributions, appear naturally in differential geometry, calculus of variations, and rational mechanics. The basic differential invariants of a dynamical Lagrangian distribution with respect to the action of the group of symplectomorphisms of the ambient symplectic manifold are the curvature operator and curvature form. These invariants can be considered as generalizations of the classical curvature tensor in Riemannian geometry. In particular, in terms of these invariants one can localize the focal points along extremals of the corresponding variational problems. In the present paper we study the behavior of the curvature operator, the curvature form, and the focal points of a dynamical Lagrangian distribution after its reduction by arbitrary first integrals in involution. An interesting phenomenon is that the curvature form of so-called monotone increasing Lagrangian dynamical distributions, which appear naturally in mechanical systems, does not decrease after reduction. It also turns out that the set of focal points to the given point with respect to the monotone increasing dynamical Lagrangian distribution and the corresponding set of focal points with respect to its reduction by one integral are alternating sets on the corresponding integral curve of the Hamiltonian system of the considered dynamical distributions. Moreover, the first focal point corresponding to the reduced Lagrangian distribution comes before any focal point related to the original dynamical distribution. We illustrate our results on the classical N-body problem. 2000 Mathematics Subject Classification. 37J15, 37J05, 53D20.     

Application of Rollout Strategy to Test Points Selection for Integer-Coded Fault Wise Table

Test points selection for integer-coded fault wise table is a discrete optimization problem. The global minimum set of test points can only be guaranteed by an exhaustive search which is eompurationally expensive. In this paper, this problem is formulated as a heuristic depth-first graph search problem at first. The graph node expanding method and rules are given. Then, rollout strategies are applied, which can be combined with the heuristic graph search algorithms, in a computationally more efficient manner than the optimal strategies, to obtain solutions superior to those using the greedy heuristic algorithms. The proposed rollout-based test points selection algorithm is illustrated and tested using an analog circuit and a set of simulated integer-coded fault wise tables. Computa- tional results are shown, which suggest that the rollout strategy policies are significantly better than other strategies.     

基于Zinc的雷达显控软件系统设计

提出了将VxWorks操作系统及其图形用户接口工具Zinc引入到雷达显控终端软件设计中的必要性,通过实例介绍了Zinc的界面设计流程,给出了某雷达显控终端软件的设计架构,着重分析了Zinc在终端软件设计中几个关键的实现技术,具有很强的实用性。