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91.
92.
叙述运用CWCO2相干激光雷达测量运动目标速度的原理和实验装置,并给出了实验结果,测速精度为0.01m/s速度分辨率为0.05m/s,外场实验表明,对于漫射目标,作用距离200m。 相似文献
93.
94.
In this paper, a new real-time sensor system has been developed to detect chatter in milling operations. In the developed sensor system, a pattern recognition technique based on an unsupervised neural network using the adaptive resonance theory (ART) is adopted for detection of milling chatter. The features on the cutting force spectrum are fed into the sensor system to classify the milling process with or without chatter. The experimental results indicate that the proposed sensor system can accurately detect milling chatter regardless of the variation in cutting conditions. 相似文献
95.
The interactions of VOHPO4· 0.5H2O and (VO)2P2O7 with the ammoxidation feed and the single components such as ammonia, oxygen, water and component mixtures were studied in detail using XRD and temperature-programmed reaction spectroscopy. The aim of this work was to improve the knowledge of the formation of the active phases or active sites of the catalysts from their precursors under the condition of the ammoxidation reaction. Similar catalytic properties of various applied VPO materials were discussed in terms of the presence of similar structure elements (domains of adjacent edge-sharing VO6 octahedra-units and P-O-NH4 groups). 相似文献
96.
Akira Ishizaki Kazuhiko Takasaki Shoji Shimomura Kouichi Masaki Kanji Kitazawa 《Electrical Engineering in Japan》1996,116(5):128-137
Although brushless resolvers have been used widely as angular position transducers, they are expensive due to their intricate construction, involving a rotary transformer to supply the exciting coils wound on the rotor poles with the current. It is shown theoretically in this paper that the resolver without rotary transformer or brushes can be realized by simple construction, which consists of the stator core with both 4-poles exciting windings and 2-poles output ones and the rotor core carrying no windings. In this resolver the rotor core has minimum gap at one side and a maximum gap at another side of the diameter. It is characterized by an outer surface form that makes the fluctuation part of gap permeance very in proportion to cos θ, where θ represents the angular position of a point in the air gap with respect to the origin on the rotor, the point of minimum air gap. The method determining the rotor form to embody the aforementioned gap permeance variation is also shown. It has been confirmed not only by simulation but also experiment that the 2-phase output voltages of a model designed based on the theory have sinusoidal waveforms with very small harmonic contents. Moreover, the rotor position detected by processing the output voltages through the conventional resolver/digital converter was within acceptable engineering accuracy. 相似文献
97.
形态学边缘检测的新算法及其应用 总被引:3,自引:0,他引:3
刘岚岚 《红外与毫米波学报》1998,17(5):386-390
提出了一种基于数学形态学的边缘检测的所算法,该算法具有简便和灵活可编程控制等优点,比原来主算法更国完善,在实际应用中有着很好的前景,并给出了实验结果。 相似文献
98.
How to study drying shrinkage microcracking in cement-based materials using optical and scanning electron microscopy? 总被引:3,自引:0,他引:3
Three different ‘destructive’ microscopy methods were tested on their ability to show drying shrinkage microcracks on a specimen cross-section. The first two were methods in which the microcracks were impregnated with a fluorescent epoxy and examined with fluorescence microscopy. In one method, the impregnation was applied before making the cross-section and in the other after making the cross-section. In the third method, the sample was kept wet constantly and examined in an environmental scanning electron microscope (ESEM). It was concluded that the method in which the dried specimen was impregnated before making the cross-section was the most reliable method to record drying shrinkage microcracks. With this method, it was possible to impregnate the complete drying shrinkage microcrack pattern in the studied cement-based materials from the surface, and there was no risk of recording microcracks introduced by sample preparation. 相似文献
99.
陈明志 《数字社区&智能家居》2006,1(12):159-160
本文对数字图像中几种具有代表性的边缘检测算子进行了理论分析,并通过VC编程实验,对各种算法进行实现,通过比较得出了各自的优缺点和适用范围。 相似文献
100.
陈希武 《中国计量学院学报》1992,(1)
本文提出并研制成补偿式光纤F-P干涉仪信号处理系统,提出了用来测量微小位移信号的三种方法及电路,即透射峰时间间隔测量法、光脉冲基波幅度测量法(精密整流法)、鉴相法。测试结果表明:时间间隔测量法,它的最大灵敏度达到0.26纳米/微秒;精密整流法,最大灵敏度为2.38纳米/伏特。 相似文献