面向对象的桌面应用框架层次模型

当前有一类加入了互联网络特色的桌面应用，如即时通和游戏等，正不断取得市场上的成功。针对这种桌面应用，从高层视角给出了一种面向对象的应用框架层次模型，以帮助这类应用的快速开发．模型分三层：管理层、主框层、大粒度GUI构件层。描述了各层的主要成分和责任，以及各层之间的关系，并在最后给出了一个实例。     

井下套管阀研究及室内试验

随着欠平衡钻井技术的深入研究和推广应用,全过程欠平衡钻井技术已成为研究热点。除了常规的欠平衡装备外,全过程欠平衡钻井还需配备井下套管阀,为此,研制了一种双液控井下套管阀。为检验该阀的使用可靠性,进行了全面的室内试验和测试,试验内容包括压力密封能力,高压、有流动情况下阀板关闭的动作准确性,模拟现场阀板下憋压时打开阀板的作业程序,检测在各种密封压力时阀的微泄漏量。试验结果表明,该阀达到设计要求,能够满足全过程欠平衡作业的工艺要求。     

垂直铺膜防渗技术在大堤防渗加固工程中的应用

在高水河大堤防渗加固工程中,根据堤身的实际情况,结合地质和施工条件,采用压力灌浆及砼地下连续墙相结合的方法来进行垂直铺膜防渗加固。通过对垂直铺膜前后测压管水头对比研究,分析了大堤外观干、湿土变化和大堤内干土质量密度、密实度的变化,说明了垂直铺膜防渗技术在大堤防渗应用造价低,防渗效果显著,有利于改善大堤的稳定性和安全性。垂直铺膜防渗技术应用于临时防渗及平原低水头水库和河道堤防等工程,实用性强,具有推广价值。     

电磁发射兵器用电容器的选取

本文首先从理论上论述了膜电容器的储能密度与寿命之间的关系，对国际电容器制造水平和趋势进行了分析，提出采用干式金属化膜电容器作为储能元件。最后，根据电磁发射兵器整体寿命配合原则，提出高储能密度脉冲电容器的合理寿命指标。     

New hybrid fuzzy controller for direct torque control induction motor drives

A new hybrid fuzzy controller for direct torque control (DTC) induction motor drives is presented in this paper. The newly developed hybrid fuzzy control law consists of proportional-integral (PI) control at steady state, PI-type fuzzy logic control at transient state, and a simple switching mechanism between steady and transient states, to achieve satisfied performance under steady and transient conditions. The features of the presented new hybrid fuzzy controller are highlighted by comparing the performance of various control approaches, including PI control, PI-type fuzzy logic control (FLC), proportional-derivative (PD) type FLC, and combination of PD-type FLC and I control, for DTC-based induction motor drives. The pros and cons of these controllers are demonstrated by intensive experimental results. It is shown that the presented induction motor drive is with fast tracking capability, less steady state error, and robust to load disturbance while not resorting to complicated control method or adaptive tuning mechanism. Experimental results derived from a test system are presented confirming the above-mentioned claims.     

A new Pd-oxide-Al/sub 0.3/Ga/sub 0.7/As MOS hydrogen sensor

A new and interesting Pd-oxide-Al/sub 0.3/Ga/sub 0.7/As MOS hydrogen sensor has been fabricated and studied. The steady-state and transient responses with different hydrogen concentrations has been measured at various temperatures. Based on the large Schottky barrier height and presence of oxide layer, the studied device exhibits a high hydrogen detection sensitivity and wide temperature operating regime. The studied device exhibits the low-leakage current and obvious current changes when exposed to hydrogen-contained gas. Even at room temperature, a very high hydrogen detection sensitivity of 155.9 is obtained when a 9090 ppm H/sub 2//air gas is introduced. Furthermore, when exposed to hydrogen-contained gas at 95/spl deg/C, both the forward and reverse currents are substantially increased with increased hydrogen concentration. In other words, the studied device can be used as a hydrogen sensor under the applied bidirectional bias. Under the applied voltage of 0.35 V and 9090 ppm H/sub 2//air hydrogen ambient, a fast adsorption response time about 10 s is found. The transient and steady-state characteristics of hydrogen adsorption are also investigated.     

高压25MW背压式汽轮机振动分析与处理

厂内一台B25汽轮机,因振动超差,进行了20个月的分析、计算和试验,最后发现中心孔内有250 g左右的油水化合物,造成转子热弯曲,激发汽轮机出现振动严重超标.     

一种计算机实时控制系统的分析及其DCS实现

简述了计算机实时控制及分布式控制系统(DCS)的一般特点．并以某型水下机器人的控制系统为例，详细介绍了一种小型实时DCS系统的具体实现。     

应用激光活化饵料藻种的研究

应用Nd:YAG激光(波长1.06μm,功率5w,照射时间0.5-3 min)和Ar+激光(波长488nm,功率70mw,照射时间5-15min)对长期保存的不同保存形式的塔胞藻(Pyramidomonassp.)进行辐照处理。研究了不同剂量激光辐照对藻体生长和叶绿素含量的影响。实验结果表明:照射剂量为60s的Nd:YAG激光及剂量为15min的Ar+激光对液体保存形式的藻种有较明显的促长效果,接种后这两种激光处理组的比生长速率分别较对照提高达53.33%和28.89%,叶绿素含量分别增加73.33%和65.69%。两种激光对液体保存藻种的活化效果均好于固体保存种。