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941.
数字图像处理技术在导弹垂直装填中的应用研究 总被引:2,自引:2,他引:0
对舰载导弹垂直发射系统装填过程中存在的问题进行了分析,针对导弹装填效率低提出了计算机控制的“抗摇摆”解决方案,然后对计算机控制的“抗摇摆”系统的分系统即定位传感器部分进行了研究,重点研究了基于视频成像技术的导弹贮运发射箱空间位置坐标测量方法,并对其中的关键技术进行了探讨,给出了图像处理结果。实验表明,该方法具有抗干扰能力强,定位精度高等特点,能够满足导弹垂直装填过程定位要求。 相似文献
942.
Yongshuang?ZhangEmail author Yongxin?Qu Guolin?Liu Shuren?Wu 《Bulletin of Engineering Geology and the Environment》2003,62(3):213-219
Miocene hard clays are widely distributed in eastern China and are associated with extensive damage to engineering structures. This paper presents the engineering geological properties of Miocene hard clays along the middle line of the North–South Diversion Water Project (NSDWP), including areas of the Nanyang Basin as well as the Fangcheng-Baofeng and Handan-Yongnian regions. Results of laboratory testing show that beneath the weathering zone the Miocene hard clays have similar engineering geological properties, including a high clay fraction with significant montmorillonite, high physico-chemical activity, high water content and high to very high shrink/swell. The effects of wetting and drying cycles on the swelling potential of the hard clays are summarized and attention drawn to the importance of these when considering excavation and construction.
相似文献
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943.
基于FPGA高速智能化视觉传感器的研究 总被引:4,自引:0,他引:4
通过FPGA技术与视觉传感技术相结合,构建了集图像采集与处理于一体的智能化视觉传感器,由于采用FPGA实现底层图像处理算法,加速了图像处理速度,提高了传感器的性能,本设计实现了视觉传感器的智能化与网络化,具有很大的应用价值。 相似文献
944.
Yang Xuejun Yi Huizhan Qu Xiangli Zhou Haifang 《Frontiers of Computer Science in China》2007,1(1):94-105
Energy consumption of parallel computers has been becoming the obstruction to higher-performance systems. In this paper, we
focus on power optimization of high-performance interconnection networks for MPI applications in high-performance parallel
computers. Compared with the past history-based work, we propose the idea of compiler-directed power-aware on/off network
links. There are some idle intervals for network links during the execution of parallel applications, at which the links still
consume large amounts of energy. Using on/off network links, compiler first divides load-balancing MPI applications into the
communication intervals and the computation intervals, and then inserts the on/off instruction into the applications to switch
the link state. To avoid the time overhead of state switching, we use a time estimation technique to analyze the computation
time, and insert the on instruction before reaching the communication intervals. Results from simulations and experiments
show that the proposed compiler-directed method can reduce energy consumption of interconnection networks by 20∼70%, at a
loss of less than 1% network latency and performance degradation. 相似文献
945.
Hongwei Qu Huikai Xie 《Journal of microelectromechanical systems》2007,16(5):1152-1161
This paper presents a deep reactive-ion etching (DRIE)-based post-CMOS micromachining process that provides robust electrically isolated single-crystal silicon (SCS) microstructures for integrated inertial sensors. Several process issues arise from previously reported three-axis CMOS microelectromechanical system (MEMS) accelerometers, including sidewall contaminations of SCS microstructures in plasma etch and a severe silicon undercut caused by overheating of suspended microstructures. Solutions to these issues have been found and are discussed in detail in this paper. In particular, a lumped-element model is developed to estimate the temperature rise on suspended microstructures in a silicon DRIE process. Based on the thermal modeling and experiments, a thick photoresist layer has been used as a thermal path to avoid the severe silicon undercut. The sidewall contamination problem is also eliminated using the modified CMOS-MEMS process. A three-axis accelerometer with a low-noise, low-power on-chip amplifier has been successfully fabricated using the new process. Footing effect was observed on the backside of the sensor microstructure, but it has little effect on the structural integrity and sensitivity of the sensor. 相似文献
946.
947.
用射频溅射的方法在强立方织构的CeO2/YSZ/Y2O3/NiW衬底上制备了YBCO超导层. 温度、气压等因素对超导层的外延生长有重要影响. 在基片温度大于780 ℃, 气压在11~160 Pa之间, 都有NiWO4化合物生成;在退火吸氧过程中, 金属基底被氧化. 最终在温度780 ℃, 气压100 Pa的条件下, 制备出了纯(00l)取向的YBCO薄膜, 其平面内φ扫描半高宽小于10°, 超导转变温度为87.2 K, 传导电流为11 A. 相似文献
948.
采用150 A·m-2的高电流密度,电解周期为10 d. 在此电流密度下如采用常规电解会造成电流效率降低和电解产品中γ-MnO2含量降低,阳极如果采用纯钛板, 还会造成阳极的严重钝化.故本实验阳极采用北京有色金属研究总院生产的钛基钛锰涂层阳极, 阴极采用紫铜板,主要通过改变悬浮颗粒加入量来研究悬浮颗粒的加入对于电解工艺的影响.通过实验表明在高电流密度下,无悬浮体或悬浮体含量较低的电解体系,电解效率较低,当悬浮颗粒含量达到或超过0.075 g·L-1时, 电解效率在98%以上.X射线衍射表明 随着悬浮颗粒加入量的增大, 电解产品中γ-MnO2含量不断增加. 相似文献
949.
目前工业档案管理面临信息、数据和知识过载、非结构化以及隐性信息、数据和知识提取三大难题。人工智能在信息、数据和知识处理方面具有很大的优势,有助于解决工业情报管理中的难题,实现工业信息情报的智能化管理,提高信息情报管理的水平,增强企业的竞争力。 相似文献
950.
Live fuel moisture content (LFMC) is one of the most important fuel properties and a critical parameter for wildland fire danger rating estimation and fire behavior analysis. Direct ground measurement of live fuel moisture content has disadvantages of high cost and limited spatial distribution extent. This paper presents an algorithm to retrieve live fuel moisture content from multiple bands of MODIS measurements. We analyzed the physical relationship between surface reflectance and live fuel moisture content using simulated MODIS measurements of diverse leaf samples, derived approximate inversion models, and proposed a semi-physical approach for live fuel moisture retrieval employing multiple MODIS bands. Using simulated MODIS measurements, the correlation coefficients between the true LFMC and estimated LFMC with our inversion models are 0.7738, 0.8397, 0.9560 and 0.9576 respectively. For validation, we tested our inversion method with woody live fuel moisture measurements at fire weather stations in Georgia. The correlation coefficients between measured LFMC and estimated LFMC with our inversion models are 0.5727, 0.6522, 0.7551, and 0.7737 respectively. Both model simulation and station measurements demonstrated advantages of our approach in accuracy. Our study suggests the potential for near real-time applications of live fuel moisture. 相似文献