用边界元法提取VLSI版图电阻

介绍了ＶＬＳＩ版图验证中电阻提取的基本原理和主要方法，给出了一种新颖的基于边界元法的电阻提取算法。该算法采用变节点单元，较好地解决了实际问题中经常出现的角点问题。通过应用该算法对几个实例进行提取，证明使用本文的算法不仅在精度上而且在占用ＣＰＵ时间上都取得了令人满意的效果     

纤维共晶生长界面前沿三维扩散场解析

修正Ｊａｃｋｓｏｎ和Ｈｕｎｔ关于在垂直生长方向截面上溶质扩散各向同性假设，求解三维Ｌａｐｏｌａｃｅ方程，获得纤维共晶生长界面前沿三维稳态扩散场，并证明Ｊａｃｋｓｏｎ和Ｈｕｎｔ的二维模型是实际生长的二维简化和一阶近似，并用丁二腈（ＳＣＮ）一梓脑（ＣＡＭ）纤维共晶系统计算生长界面前沿溶质分布。     

Influence of gas composition on recurrence of atelectasis after a reexpansion maneuver during general anesthesia

BACKGROUND: Atelectasis, an important cause of impaired gas exchange during general anesthesia, may be eliminated by a vital capacity maneuver. However, it is not clear whether such a maneuver will have a sustained effect. The aim of this study was to determine the impact of gas composition on reappearance of atelectasis and impairment of gas exchange after a vital capacity maneuver. METHODS: A consecutive sample of 12 adults with healthy lungs who were scheduled for elective surgery were studied. Thirty minutes after induction of anesthesia with fentanyl and propofol, the lungs were hyperinflated manually up to an airway pressure of 40 cmH2O. FIO2 was either kept at 0.4 (group 1, n = 6) or changed to 1.0 (group 2, n = 6) during the recruitment maneuver. Atelectasis was assessed by computed tomography. The amount of dense areas was measured at end-expiration in a transverse plane at the base of the lungs. The ventilation-perfusion distributions (VA/Q) were estimated with the multiple inert gas elimination technique. The static compliance of the total respiratory system (Crs) was measured with the flow interruption technique. RESULTS: In group 1 (FIO2 = 0.4), the recruitment maneuver virtually eliminated atelectasis for at least 40 min, reduced shunt (VA/Q < 0.005), and increased at the same time the relative perfusion to poorly ventilated lung units (0.005 < VA/Q < 0.1; mean values are given). The arterial oxygen tension (PaO2) increased from 137 mmHg (18.3 kPa) to 163 mmHg (21.7 kPa; before and 40 min after recruitment, respectively; P = 0.028). In contrast to these findings, atelectasis recurred within 5 min after recruitment in group 2 (FIO2 = 1.0). Comparing the values before and 40 min after recruitment, all parameters of VA/Q were unchanged. In both groups, Crs increased from 57.1/55.0 ml.cmH2O-1 (group 1/group 2) before to 70.1/67.4 ml.cmH2O-1 after the recruitment maneuver. Crs showed a slow decrease thereafter (40 min after recruitment: 61.4/60.0 ml.cmH2O-1), with no difference between the two groups. CONCLUSIONS: The composition of inspiratory gas plays an important role in the recurrence of collapse of previously reexpanded atelectatic lung tissue during general anesthesia in patients with healthy lungs. The reason for the instability of these lung units remains to be established. The change in the amount of atelectasis and shunt appears to be independent of the change in the compliance of the respiratory system.     

双迭片弯曲压电陶瓷换能器及振动模态分析测量

介绍了双迭片弯曲压电陶瓷换能器的制作及边缘固定金属压电陶瓷双迭片弯曲振动，并利用有限元分析了换能器的谐振模式，采用激光多普勒干涉仪对换能器的谐振特性以及振动速度和位移分布进行了测量和分析，结果表明：换能器空载性能良好，通过有限元分析与先进测量手段的结合，能够对换能器器件的制作与分析进行指导。     

松香及其衍生物在浮选分离中的应用

介绍了松香的来源、化学组成及理化性质；讨论了松香及其衍生物在非硫化物矿浮选分离、有色金属离子的浮选分离以及从水溶液中浮选分离有机物等方面的应用情况。     

前馈和反馈相结合的控制策略在宝钢线材厂控冷轧线上的应用实践

在详细分析料坯在水箱内冷却热过程特点的基础上，提出了前馈和反馈相结合的水流量优化控制策略，并将该策略应用于宝钢线材厂控冷轧线上。实际运行结果表明：该策略能够合理地控制水箱水流量，从而保证了线材水箱出口处的温度满足工艺要求，大大提高了线材成品的质量。所做工作对国内同类企业有重要的意义。     

石英晶体监控法镀制高精度光学薄膜

讨论了石英晶体监控法在光学薄膜镀制过程中的应用原理。通过与常规的光学监控法镀制的膜层相比较．证实了石英晶体监控法有助于提高光学薄膜的光学品质。试验表明所镀膜层的光学性能优异，在光通信和激光器等领域具有广阔的应用前景。     

齐莱姆水电站机组制造分包的合理性分析

葛洲坝集团有机电建设有限公司在齐莱姆水电站机电标的投标过程中，通过对各方向情况的了解和分析，同捷克斯可达公司就机组制造签定了分包协议，达到了增投标竞争力，确保履约顺利，转移和消除风全的目的。