DCS的现状与发展趋势

叙述ＤＣＳ的进展。目前的ＤＣＳ正面临来自用户需求的挑战，为保住全球市场竞争优势，制造加工行业用户需要建立集过程控制数据与商业信息于一体的ＣＩＭＳ。未来ＤＣＳ应具备服从国际标准的开放性和互换操作性。以ＩＳＰ现场总线为基础的系统结构可能成为未来的ＤＣＳ。提高应用水平有助于发展未来的ＤＣＳ     

一种高分辨力柔性触觉传感器

本文描述了一种基于全内反射原理，用透明橡胶材料作为波导板的柔性触觉传感器。该传感器除具有一般刚性波导板触觉传感器的高分辨力等特点外，还具有柔性好，力灵敏阈值低，不怕碰撞等特点，该传感器特别适合装在智能机器人手爪上，为机器人系统高效率地获取物体形状，位置和姿态信息，实现智能抓握物体，操作物体等功能提供了有效的手段。     

韩江三角洲海岸变迁遥感调查研究

利用1:10万TM影像，对广东东部韩江三角洲地区的海岸变迁及河道演变进行了调查研究。划分了不同时期的海岸界线和古河道遗迹，提出韩江三角洲的形成是河流动力和海洋动力共同作用的结果，对研究历史海平面变化及环境演变具重要意义。     

A mechanism for transgranular stress-corrosion cracking

A model is proposed to explain transgranular-stress corrosion cracking (T-SCC) in face-centered cubic (fcc) materials. Crack propagation is shown to be anisotropic, in that growth near {110} < 001> is discontinuous due to crack arrest by dislocation blunting whereas growth away from this growth orientation is continuous. For the former case, renucleation of arrested cracks involves active dissolution of shear bands at the crack tip, which changes the stress state at Lomer-Cottrell locks, causing them to fail by cleavage. Once the crack is nucleated, its instantaneous macroscopic crack-growth velocity is considered to be comprised of multiple nucleation of microcracks with intervening arrests. This microcracking results from the interaction of the stress fields from neighboring cracks which are forming simultaneously, the crack-opening constraint due to ligaments which act as “bridges” behind the crack front, and the localized dissolution at the microcrack tip which affectsK _IC and leads to the “cobblestone” appearance. Experimental evidence and theoretical considerations are presented to support the model. The system studied was Cu-25 at. pct Au in 0.6 M NaCl solution at potentials between 300 and 400 mV (sce), which precludes hydrogen embrittlement. This article is based on a presentation made in the symposium “Quasi-Brittle Fracture” presented during the TMS fall meeting, Cincinnati, OH, October 21–24, 1991, under the auspices of the TMS Mechanical Metallurgy Committee and the ASM/MSD Flow and Fracture Committee.     

The current aspects of seroepidemiological research in combined foci of leishmaniasis

The accuracies of ultrasonography (US) and computed tomography (CT) for determining tumor invasion of the chest wall in lung cancer were compared in a retrospective study of 120 patients. US findings were evaluated preoperatively according to the following criteria: disruption of pleura, extension through the chest wall, and fixation of tumor during breathing. CT findings were evaluated with the following criteria: obtuse angle of the mass to the pleural surface, more than 3 cm contact with the pleural surface, and visible pleural thickening associated with the mass. Chest wall invasion was judged as positive when at least two of the three findings were present with either technique. Nineteen of the 120 patients had chest wall invasion by tumor. The sensitivity of US was 100% and the specificity was 98%. The sensitivity of CT was 68% and the specificity was 66%. The accuracy of US and CT were 98% and 67%, respectively.     

A Linear Cross-Coupled Control System for High-Speed Machining

We present a linear cross-coupled controller to improve highspeed contouring accuracy independently of tracking accuracy in a biaxial machine tool feed drive servomechanism. Unlike conventional cross-coupled controllers, the cross-coupled controller presented here is a linear system, so it is very easy to perform the stability and steady-state error analysis, and to optimise the controller parameters. The proposed controller is evaluated experimentally on a CNC LOM machine and compared to an uncoupled controller and a conventional cross-coupled controller. Controller performance is evaluated for a circular contour at a feedrate of 30 m min _1 . The experimental results show that the proposed controller can greatly reduce the contour error at large feedrates. The linear cross-coupled controller is simple to implement and is practical.     

自动力套管补贴加固技术及其在B125井的应用

随着油田开发时间的延长，油水井井下套管的损坏将越来越严重，套管故障井将越来越多，为了恢复套损井生产，将套管损坏所造成的损失降到最低，在配套波纹管补贴，水动力补贴，爆炸补贴等专门修套技术的基础上，通过认真调查研究，又配套了操作方便简单，适用套管损坏类型广的自动力套管补贴加固技术，使各种套管变形，套管断错（错开没有位移或位移量不大时）、套管破裂，误射孔井段封堵，已射开水层封堵等修井作业的难度进一步降低，从而进一步提高了修复井综合开发经济效益。     

既有钢筋混凝土框架结构抗震加固若干问题探讨

针对钢筋混凝土框架结构抗震加固问题的复杂性 ,本文深入分析了抗震加固结构的受力特征 ,探讨了卸荷对加固构件承载力的影响 ,并针对抗震加固后的“隐含危险转移”问题提出了相应的对策。最后 ,提出了抗震加固的基本原则 ,可供结构抗震加固时参考     

预处理工艺对硬质合金与金刚石膜间粘结力的影响

在两种经不同预处理的硬质合金YG8基底上，采用微波等离子体化学气相沉积法，在微波功率2kW，压强4.0kPa和6.5kPa，CH4和H2流量分别为1.6cm/s和100.0cm/s的条件下生长金刚石薄膜。利用X射线衍射检测了金刚石薄膜是否存在，用拉曼光谱分析了薄膜的质量，用金相显微镜观察了薄膜的洛氏硬度压痕，标定并比较了不同预处理工艺膜与基底的结合力。实验结果表明，不同的预处理方法对于粘结力的影响不大，最主要的因素是钴含量的多少。     

异丙苯在Cu-HMS分子筛上的催化氧化

以含Cu的中孔分子筛(Cu-HMS)为催化剂,研究异丙苯的催化氧化。研究发现,Cu-HMS催化剂的加入使异丙苯氧化的诱导期显著缩短。在75℃下,以Cu-HMS为催化剂,O2为氧化剂的纯异丙苯氧化反应,苯乙酮为主要副产物,反应的选择性和转化率都很高。当催化剂用量为1 5×10-4mol/ml时,反应8h后,异丙苯转化率为32 7%,目的产物的累积浓度(质量分数)为37 7%,选择性为99%;反应12h后,异丙苯转化率为42 4%,目的产物的累积浓度为46 3%,选择性为95 6%。