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31.
微波仪器远程自动测试系统的设计与实现 总被引:3,自引:1,他引:2
针对大多通信测试仪器仅局限于本地测试监控的现状,提出了一种将本地测试仪器用于对远程微波设备进行测试监控的开发模式,从而实现了远程仪器的自动化测试。分别就系统中的关键技术和交互方式作了详细的介绍,得出系统具有较强的可扩展性,且简单易操作的特点,相信该系统会有广阔的的应用前景。 相似文献
32.
Cu—Zn—Al系合金热弹性马氏体相变的热滞 总被引:3,自引:0,他引:3
韩明 《有色金属材料与工程》1997,18(2):53-55
本文通过热处理工艺及添加第四组元研究了Cu-Zn-Al系记忆合金的相变热滞。结果表明,淬火冷却速度影响合金的相变热滞大小,随着母相时效时间的延长,马氏体相变热滞变大.Mn元素的加入可以减小CU-Zn-Al合金相变热滞. 相似文献
33.
在一定实验条件下,屏蔽暂堵的反排解堵效率随压差、温度的增大而增大,反排解堵在很短的时间内就可完成。一般的反排解堵率都在60%以上,但反徘不能完全解堵。 相似文献
34.
M. S. Han S. R. Hahn H. C. Kwon Y. Bin T. W. Kang J. H. Leem Y. B. Hou H. C. Jeon J. K. Hyun Y. T. Jeoung H. K. Kim J. M. Kim T. W. Kim 《Journal of Electronic Materials》1998,27(6):680-683
Double-crystal x-ray rocking curve (DCRC) and secondary-ion mass-spectroscopy (SIMS) measurements have been performed to investigate the effect of rapid thermal annealing on the interdiffusion behavior of Hg in HgTe/CdTe superlattices grown on Cd0.96Zn0.04Te (211)B substrates by molecular beam epitaxy. The sharp satellite peaks of the DCRC measurements on a 100-period HgTe/CdTe (100Å/100Å) superlattice show a periodic arrangement of the superlattice with high-quality interfaces. The negative direction of the entropy change obtained from the diffusion coefficients as a function of the reciprocal of the temperature after RTA indicates that the Hg diffusion for the annealed HgTe/CdTe superlattice is caused by an interstitial mechanism. The Cd and the Hg concentration profiles near the annealed HgTe/CdTe superlattice interfaces, as measured by SIMS, show a nonlinear behavior for Hg, originating from the interstitial diffusion mechanism of the Hg composition. These results indicate that a nonlinear interdiffusion behavior is dominant for HgTe/CdTe superlattices annealed at 190°C and that the rectangular shape of HgTe/CdTe superlattices may change to a parabolic shape because of the intermixing of Hg and Cd due to the thermal treatment. 相似文献
35.
蒙特卡罗方法在空间辐射制冷器理论分析及热设计计算中的应用 总被引:1,自引:1,他引:0
介绍了二级抛物面型辐射制冷器的热物理模型及用蒙特卡罗方法数值模拟解决其热流理论和辐射热耦合表面(漫发射、镜反射)辐射热交换的处理方法。 相似文献
36.
The incidence of stress fractures is increasing among competitive and recreational athletes as well as among children and the elderly. By understanding the continuum of bone's response to stress and maintaining an appropriate index of suspicion, the health care provider can diagnose these injuries appropriately. An accurate history and examination is essential and will differentiate stress fractures from other stress reactions. The more common stress fractures are discussed. 相似文献
37.
PC/PET共混物的非等温结晶动力学 总被引:9,自引:0,他引:9
采用等速变温DSC法对PC/PET共混体系的非等温结晶动力学进行了研究,结果表明,从玻璃态结晶时,随着PC含量的增加,PET组分的结晶速率先增加后降低。耐从熔体结晶时,体系的结晶速率随着PC含量的增加而增加,讨论了PC对PET组分结晶过程的影响。 相似文献
38.
Cheol-Min Park Byung-Hyuk Min Jae-Hong Jun Juhn-Suk Yoo Min-Koo Han 《Electron Device Letters, IEEE》1997,18(1):16-18
We have fabricated a self-aligned offset-gated poly-Si thin film transistor (TFT) by employing a novel photoresist reflow process. The gate structure of the new device is consisted of two unique patterns: A main-gate and a sub-gate. The new fabrication method extends the gate-oxide over the offset region. With the assistance of the sub-gate and reflowed photoresist a self-aligned offset region is successfully obtained due to the offset oxide acting as an implantation mask. The poly-Si TFT with symmetrical offsets is easily fabricated and the new method does not require any additional offset mask step. Compared with the misaligned offset gated poly-Si TFTs, excellent symmetric electrical characteristics are obtained 相似文献
39.
Motoharu Fujigaki In Hong Yang Yoshiharu Morimoto Eung Kyo Han 《NDT & E International》1996,29(4):197-203
There is no good method to measure the shape and the strain distributions of a structure changing with time. We have previously proposed the Fourier transform grid method (FTGM) to measure the three-dimensional shape and surface strain distributions of stationary objects by analysing the two-dimensional grating images recorded with two cameras. In the stereoscopic method, it is very important to determine the accurate geometric parameters of the camera system. In this paper, the positions and the directions of cameras are accurately determined using the FTGM applied to images of a reference object on which a two-dimensional grating is drawn. Applications for analysing shape and strain distributions of vibrating rubber plates and a moving human skin are shown. 相似文献
40.
Gang Chen Zhonghua Yang Chor Ping Low 《Industrial Informatics, IEEE Transactions on》2006,2(4):269-280
In this paper, we address agent coordination from a dynamic systems perspective and propose a dynamic coordination model, which is inspired by biological metabolic systems. A new coordination mechanism through dynamic local adjustment (CDLA) is presented, and coordination is achieved when every agent utilizes explicitly the global system dynamics and performs iteratively a dynamic local adjustment procedure. The CDLA mechanism is investigated in an example multiagent shop floor system. The results show that the example manufacturing process is well-coordinated and the coordination approach is practically applicable and effective 相似文献