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131.
介绍了在VISUAL BASIC环境中研华公司的ADAM-5510数据采集控制器和上位机通信实现的方法。 相似文献
132.
The dynamic properties of the assistant sounders in the black cicada are given and the twitching properties of Contraction in the sounding muscle are revealed in this paper.For the operculum, tymbal cover and joint membrane, each of their vibration periods consists of three subgroup vibrations (SGV_(a,b,c)) corresponding to amplitude-modulation pulse trains (AMPT_(1,2,3)) in every syllable of synchro song. In comparison with the vibration at dorsum, the SGV_(a-c) have a subband with the function of regulating the tone. During calling song continuously, the pressure change inside the resonant cavity and the airspeed through the spiracles on both sides are about 7. 94—15.88 Paand 0.59—0.84 cm~3/s respectively, and they increase by about 7 and 2.6 times as the abdomen is moved. When the contraction motion of the sounding muscle comes up to the critical Sounding state, it further produces the twitching process, and drives the sounding membrane and the toning plate-membrane to produce AMPT_(1-3) and SGV_(a 相似文献
133.
134.
Imatinib is an important anticancer drug, which binds specifically to the Abl kinase and blocks its signalling activity. To model imatinib:protein interactions, we have developed a molecular mechanics force field for imatinib and four close analogues, which is consistent with the CHARMM force field for proteins and nucleic acids. Atomic charges and Lennard‐Jones parameters were derived from a supermolecule ab initio approach. We considered the ab initio energies and geometries of a probe water molecule interacting with imatinib fragments at 32 different positions. We considered both a neutral and a protonated imatinib. The final RMS deviation between the ab initio and force field energies, averaged over both forms, was 0.2 kcal/mol. The model also reproduces the ab initio geometry and flexibility of imatinib. To apply the force field to imatinib:Abl simulations, it is also necessary to determine the most likely imatinib protonation state when it binds to Abl. This was done using molecular dynamics free energy simulations, where imatinib is reversibly protonated during a series of MD simulations, both in solution and in complex with Abl. The simulations indicate that imatinib binds to Abl in its protonated, positively‐charged form. To help test the force field and the protonation prediction, we did MD free energy simulations that compare the Abl binding affinities of two imatinib analogs, obtaining good agreement with experiment. Finally, two new imatinib variants were considered, one of which is predicted to have improved Abl binding. This variant could be of interest as a potential drug. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010 相似文献
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136.
为满足复杂航天光学系统对精度的要求,克服传统基准传递技术与计算机辅助装调技术对多于3片反射镜的复杂光学系统进行装调时存在的局限性,提出了两种技术相结合的装调方法。采用提出的方法对三镜消像散(TMA)空间相机进行了装调,结果显示:三镜在Y向和Z向的失调量分别由18.651和9.879 mm降低到1.036和0.102 mm,系统波前差达到全视场平均值1/14λ(RMS)。结果证明:此方法能有效缩短装调时间并达到系统要求的精度指标,对于多镜复杂光学系统装调具有指导和参考价值。 相似文献
137.
通过学习和研究建构主义教学模式,结合多年的大学物理实验教学经验,在教学中有意识地运用建构主义的教学方法(如支架式教学),提高了大学物理实验的教学效果. 相似文献
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139.
介绍了阿贝-波特空间滤波的实验原理,在Matlab环境下建立了带有图形用户界面(GUI)的计算机仿真平台.不仅可以准确地完成针对不同输入图像、不同滤波要求的滤波过程,还可以通过调整滤波器参数观察滤波效果的差异,形象地展现光学空间滤波过程的物理本质,提高教学效果. 相似文献
140.
In this work, a detailed mathematical and physical model for calculating the fluidic impedance of an artery is developed. Initially, the model calculates the impedance of a healthy artery, and then, it compares this with the alteration in the impedance of an artery with atherosclerosis. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献