小型机载数字视频记录系统的设计与实现

采用嵌入式控制模块SOM2386和专用视频处理芯片SZ1510,设计和实现了一种基于电子硬盘存储的嵌入式小型机载数字视频记录系统。给出了系统总体方案,阐述了视音频解码编码、接口、控制及存储单元的硬件设计,介绍了系统的软件设计,并给出了系统软件的整体工作流程。该系统体积小、重量轻、抗震性好、使用维护方便,已在某型飞机上得到应用。     

N-苄基丙烯酰胺的合成

以丙烯腈和苯甲醇为原料，浓硫酸作催化剂，合成了N-苄基丙烯酰胺（N-BAA）。考察了反应温度、反应时间和催化剂用量等因素对产物收率的影响，得出了最佳反应条件：n（丙烯腈）：n（苯甲醇）：n（浓硫酸）=3：1：1．2，反应时间3h，反应温度60℃。在最佳条件下，N-BAA的收率可达92％。每100g粗产物用10％氢氧化钠溶液提纯，精制产物纯度可达99．80％，熔点为64～65℃。通过红外光谱对产物结构进行了表征。     

D.c. conduction studies on thermally evaporated neodymium oxide thin films

Aluminium-neodymium oxide-aluminium thin film capacitors have been prepared by thermal evaporation and the d.c. conduction properties of these films have been studied. The thicknesses of the films have been determined by a multiple beam interferometer. The current-voltage power-law dependence showed that the conduction in these films is space-charge limited. The linear dependence of the current density on the square root of the applied field confirmed the exponential trap distribution. The trap density has been found to be of the order of 10²⁶ m^–3. It has also been observed that the Schottky type of conduction is predominant in the high-field region and the height of the Schottky barrier has been determined. It is seen that the conduction mechanism is an activated process with the activation energy decreasing with increasing field.     

彩色PDP用玻璃基板

本文讨论了彩色ＰＤＰ现用钠钙玻璃的热稳定性，指出由于这种玻璃在热处理过程中易变形和收缩，因而不适合作大面积彩色ＰＤＰ基板材料，介绍了彩色ＰＤＰ基板玻璃的制造方法和特点。最后介绍了日本旭硝子公司和美国康宁公司各自为彩色ＰＤＰ新开发的玻璃基板材料ＰＤ２００和ＣＳ２５。     

同步辐射晶体单色器晶体热应变的模拟与实验结果的比较

报道了同步辐射装置光束线关键部件之一的晶体单色器晶体热应变的ANSYS有限元模拟结果,并与实验结果进行了比对,模拟结果在实验误差范围(约士15%)内与实验数据符合,证明了模拟结果的可靠性.     

Electron-beam controlled switching using quartz and polycrystallineZnS

Results of electron-beam controlled switching experiments with switch samples of quartz crystal and polycrystalline zinc selenide (ZnSe) are presented. For switch samples of both materials, drastic reductions of the switch resistance were induced by the electron beam. The quartz sample showed very fast temporal response (less than 1 ns) with potential applicability for current control. The ZnSe samples, on the other hand, showed longer current transients (on the order of 10 ns) with exponential development of the switch resistance after the electron beam pulse     

YAG：Nd激光照射犬气管粘膜的实验研究

An experimental study for the pathologic changes of the canine tracheal mucosa under YAG:Nd laser ablation was performed in order to master the appropriate parameters for the clinical treatment of YAG:Nd laser. 6 male and female Mongolia dogs weighing 13-18 kg were received 20W YAG:Nd laser treatment and their pathologic changes were examined instantly and 3, 7, 14 and 28 days after ablation.     

Constrained Drying of Aqueous Yttria-Stabilized Zirconia Slurry on a Substrate. I: Drying Mechanism

Aqueous yttria-stabilized zirconia slurry was cast on a substrate to form wet coatings. Both weight loss and thickness reduction were measured, during the drying process. Lateral drying was observed by in situ monitoring of the coating surface. The drying kinetics were classified as an initial constant rate period (CRP), followed by a falling rate period (FRP). Thickness reduction occurred in the CRP stage, and was uneven across the coating because of lateral flow. As tensile stresses developed within the coating because of the constrained volume shrinkage, crack formation and propagation occurred in the FRP stage and affected the drying rate.     

基于DTC的井下架线式电机车变频调速装置设计与应用

分析了井下架线式电机车运行现状及存在的维护量大、维护成本高、故障率高等问题.设计了一种基于DTC的电机车电机变频调速装置,现场应用情况表明其具有起动力矩大、维护量小、故障率低、节约成本的优点.指出了应用DTC变频调速技术改造传统的矿用架线式电机车直流传动系统的必要性及应用前景.     

Modal Kalman filtering based impedance relaying

An algorithm is presented for computer distance relaying. It is based on modal Kalman filtering (MKF) to estimate fundamental phasors, MKF exploits all the measurement information available from a three-phase line and is founded on enhanced models of the electromagnetic transients noise. To support the modeling of noise for different faults, a study of nontrivial electrical networks with accurate electromagnetic transients modeling is made for 400 kV transmission lines. MKF fits the behavior of the different modal noise for the Clarke phasors, but it is invariant for each type of fault, assuring robustness and minimum error variance. To computer distance, Clarke αB phasors are transformed to +/- symmetrical components, and then a well-known expression is used to computer the positive impedance. Statistical analysis if presented to assess observation time versus estimation accuracy for the different types of line faults