精密扇形扫描稳速控制

在扇形扫描中，马达稳速的控制是通过相位补偿实现的。本文提出一种新的稳速控制方法、相位补偿控制，并介绍了相位补偿电路的设计。     

Mesh‐independent p‐orthotropic enrichment using the generalized finite element method

This paper is aimed at presenting a simple yet effective procedure to implement a mesh‐independent p‐orthotropic enrichment in the generalized finite element method. The procedure is based on the observation that shape functions used in the GFEM can be constructed from polynomials defined in any co‐ordinate system regardless of the underlying mesh or type of element used. Numerical examples where the solution possesses boundary or internal layers are solved on coarse tetrahedral meshes with isotropic and the proposed p‐orthotropic enrichment. Copyright © 2002 John Wiley & Sons, Ltd.     

一种网格结构的雷达信号处理单元

介绍了一种采用网络结构，使用五片SHARC芯片组成的相控阵雷达信号处理单元。并介绍了此单元上基于IEEE1149.1边界扫描标准的故障诊断系统。     

Reducing Average and Peak Test Power Through Scan Chain Modification

Parallel test application helps reduce the otherwise considerable test times in SOCs; yet its applicability is limited by average and peak power considerations. The typical test vector loading techniques result in frequent transitions in the scan chain, which in turn reflect into significant levels of circuit switching unnecessarily. Judicious utilization of logic in the scan chain can help reduce transitions while loading the test vector needed. The transitions embedded in both test stimuli and the responses are handled through scan chain modifications consisting of logic gate insertion between scan cells as well as inversion of capture paths. No performance degradation ensues as these modifications have no impact on functional execution. To reduce average and peak power, we herein propose computationally efficient schemes that identify the location and the type of logic to be inserted. The experimental results confirm the significant reductions in test power possible under the proposed scheme.     

构筑企业级信息系统安全体系

本文以跨地区公司为例,探讨企业级信息系统安全体系的构筑,所述的原则和做法可以实现在外部网-内部网-主机-用户体系上,形成多道防线,使企业计算机网络具有相当程度的安全性,从而达到企业信息系统的安全目标。     

基于条码扫描的特种冰箱集存库系统设计与应用

本文将条码扫描器应用于特种冰箱的制造中,建立了一种新型全自动集存库系统,重点分析了本系统的工作原理和硬件配置,及PLC的程序设计和触摸屏组态软件设计。     

PROGRESS IN THE MODELLING OF AIR FLOW PATTERNS IN TIMBER KILNS

Progress in modelling air flow patterns in timber kilns using Computational Fluid Dynamics is reviewed in this work. These simulations are intended to predict the distribution of the flow in the fillet spaces between boards in a hydraulic model of a timber kiln. Here, the flow regime between the boards is transitional between laminar and turbulent flow, with Reynolds numbers of the order of 5000. Running the simulation as a transient calculation has shown few problems with convergence issues, reaching a mass residual of 0.2% of the total inflow after 40-100 iterations per time step for time steps of 0.01 s. Grid sensitivity studies have shown that non-uniform grids are necessary because of the sudden changes in flow cross section, and the flow simulations are insensitive to grid refinement for non-uniform grids with more than 300,000 cells. The best agreement between the experimentally-measured flow distributions between fillet spaces and those predicted by the simulation have been achieved for (effective) bulk viscosities between the laminar viscosity for water and ten times that value. This change in viscosity is not very large (less than an order of magnitude), given that effective turbulent viscosities are typically several orders of magnitude greater than laminar ones. This result is consistent with the transitional flows here.     

Partitioning multiple objective optimal solutions with applications in radiotherapy design

The optimal partition for linear programming is induced by any strictly complementary solution, and this partition is important because it characterizes the optimal set. However, constructing a strictly complementary solution in the presence of degeneracy was not practical until interior point algorithms became viable alternatives to the simplex algorithm. We develop analogs of the optimal partition for linear programming in the case of multiple objectives and show that these new partitions provide insight into the optimal set (both pareto optimality and lexicographic ordering are considered). Techniques to produce these optimal partitions are provided, and examples from the design of radiotherapy plans show that these new partitions are useful. A. Holder. Research conducted at Trinity University, TX, and The University of Mississippi, MS. This research was partially supported by ONR Grant N00014-01-1-0917.     

空爆毁伤地面机动目标扫描准则研究

文中主要针对多爆炸成型弹丸空爆战斗部,在分析区域识别和占空比识别两种不同扫描准则的基础上,应用蒙特卡洛方法计算了战斗部对目标的毁伤概率.通过仿真计算结果对比分析,获得了不同扫描准则对毁伤概率的影响,结果可为多爆炸成型弹丸空爆战斗部设计和选择使用扫描准则提供参考依据.     

三体磨料塑变磨损中磨粒运动方式的研究

对三体磨料磨损中磨粒的运动方式做了进一步的理论分析，基于三体磨料磨损中塑变疲劳磨损起主要作用，为突出塑变疲劳磨损的作用，选择圆形磨料进行研究，分析了圆整磨料在三体磨料磨损界面中滚动、滑动的判定，提出了相对滑动界面的判定。