NUMERICAL STUDY OF TOPOLOGICAL STRUCTURE OF 3-D TRANSONIC VISCOUS FLOW FIELD (TVFF) INSIDE TURBINE CASCADE

ＮＵＭＥＲＩＣＡＬＳＴＵＤＹＯＦＴＯＰＯＬＯＧＩＣＡＬＳＴＲＵＣＴＵＲＥＯＦ３ＤＴＲＡＮＳＯＮＩＣＶＩＳＣＯＵＳＦＬＯＷＦＩＥＬＤ（ＴＶＦＦ）ＩＮＳＩＤＥＴＵＲＢＩＮＥＣＡＳＣＡＤＥＧｕｏＹａｎｈｕ，ＳｈｅｎＭｅｎｇｙｕ，ＷａｎｇＢａｏｇｕｏ（Ｄｅ...     

某型战机追踪导引研究

基于对广泛应用与研究的各种比例导引律的比较与分析，提出应用纯比例导引实现战机追踪导引的方法，并通过追踪以不同机动方式逃逸的飞行目标的仿真，说明了它的正确性与可行性。     

VLSI积木块布图设计中一种提高布通率的总体布线算法

论述了积木块布图设计中一种旨在提高布通率的总体布线算法。该算法以求解最小斯坦纳树算法为基础，采用总体布线资源动态调整，不断优化的方法，获得很高的布通率，该算法在ＶＬＳＩ－ＣＡＤ系统中应用取得很好的效果。     

电子侦察系统中分布式光传输的同步技术

针对网络化电子侦察中数据多径传输的同步性问题,设计了一种新型的分布式光传输技术方案。构造了Unique ID数据包作为传输单元,用于平衡不同信道的延时差异。在保证数据高速实时传输的前提下,能够较好地实现多源、多节点复杂网络中数据的同步传输。     

工程常见塔间距下大型冷却塔的双塔干扰效应

针对工程常见塔间距下冷却塔双塔干扰效应采用风洞试验方法进行研究,通过增加模型表面粗糙度来补偿模型试验的雷诺数效应,变化塔间距和风向角进行125种工况的风洞试验,进行基于有限元的风致响应计算,获得不同风向角和塔间距下的整体风荷载和风致响应,并以此进行双塔的干扰效应研究。研究发现双塔并行放置时,由于"狭缝效应"的存在使得顺风向塔底剪力的干扰系数大于1,此时塔间距越小,干扰效应越显著;本文研究的塔间距下基于多组风荷载和风致响应指标的干扰系数最大值约为1.15;顺风向塔底剪力和弯矩的干扰系数最大值大约出现在67.5°风向,基于风致响应指标的最大值出现在90°≤θ≤150°之间的风向。     

Evaluation of Characteristics of Non-Metallic Inclusions in P/M Ni-Base Superalloy by Automatic Image Analysis

Non-metallic inclusions,especially the large ones,within P/M Ni-base superalloy have a major influence on fatigue characteristics,but are not directly measurable by routine inspection.In this paper,a method,automatic image analysis,is proposed for estimation of the content,size and amount of non-metallic inclusions in superalloy.The methodology for the practical application of this method is described and the factors affecting the precision of the estimation are discussed.In the experiment,the characteristics of the non-metallic inclusions in Ni-base P/M superalloy are analyzed.     

钢制螺栓镀锌后脆性断裂分析

着重分析了钢制螺栓镀锌后产生脆性断裂的原因及应采取的预防措施.     

Research and Development of Ceramic Cutting Tools in China

The research and development of various classes of ceramic cutting tools in China are described,because manufacturing efficiency is fundamental to the growth of China's economy.     

试谈我国IT企业的营销及其对策

与工商企业不同，ＩＴ企业具有市场需求的多样性、高风险性等营销特点。面对国内外企业的竞争，我国ＩＴ企业应根据其营销特点，制定出相应的宏观战略和微观策略。     

The plasma sheet and boundary layers under northward IMF: A multi-point and multi-instrument perspective

During conditions of northward interplanetary magnetic field (IMF), the near-tail plasma sheet is known to become denser and cooler, and is described as the cold-dense plasma sheet (CDPS). While its source is likely the solar wind, the prominent penetration mechanisms are less clear. The two main candidates are solar wind direct capture via double high-latitude reconnection on the dayside and Kelvin–Helmholtz/diffusive processes at the flank magnetopause. This paper presents a case study on the formation of the CDPS utilizing a wide variety of space- and ground-based observations, but primarily from the Double Star and Polar spacecraft on December 5th, 2004. The pertinent observations can be summarized as follows: TC-1 observes quasi-periodic (∼2 min period) cold-dense boundary layer (compared to a hot-tenuous plasma sheet) signatures interspersed with magnetosheath plasma at the dusk flank magnetopause near the dawn-dusk terminator. Analysis of this region suggests the boundary to be Kelvin–Helmholtz unstable and that plasma transport is ongoing across the boundary. At the same time, IMAGE spacecraft and ground based SuperDARN measurements provide evidence of high-latitude reconnection in both hemispheres. The Polar spacecraft, located in the southern hemisphere afternoon sector, sunward of TC-1, observes a persistent boundary layer with no obvious signature of boundary waves. The plasma is of a similar appearance to that observed by TC-1 inside the boundary layer further down the dusk flank, and by TC-2 in the near-Earth magnetotail. We present comparisons of electron phase space distributions between the spacecraft. Although the dayside boundary layer at Polar is most likely formed via double high-altitude reconnection, and is somewhat comparable to the flank boundary layer at Double Star, some differences argue in favour of additional transport that augment solar wind plasma entry into the tail regions.