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51.
随着使用电脑作为信息来源的与日俱增,触摸屏以其易于使用、坚固耐用、反应速度快、节省空间、易于交流等优点,并作为一种最为友善的人机接口在平板电脑上的应用也会越来越普及.针对上述实际状况,该文介绍了平板电脑触摸屏性能试验的技术依据,试验方法和程序. 相似文献
52.
Xu Cheng Rong Jiawei Chen Yulin Wu Hang Duan Shihong 《International Journal of Wireless Information Networks》2022,29(1):1-13
International Journal of Wireless Information Networks - Source seeking problem has been faced in many fields, especially in search and rescue applications. We proposed a virtual structure-based... 相似文献
53.
54.
信号的自动识别是非协作通信领域研究的重要课题。通过对现有研究成果的应用,针对实际工程给出一种基于时频域处理的MSK信号调制识别算法。该算法结构简单,计算量较小,具有较好的识别性能。 相似文献
55.
The structural and electronic properties of a pentacene monolayer adsorbed on the Au(1 1 1) surface have been studied with a density-functional theory (DFT) approach. A thermally stable adsorption geometry of the pentacene monolayer on the gold surface is found, from which the adsorption energy per pentacene molecule can be evaluated. Our results illustrate how the electron charge distribution initially present over the clean gold surface is pushed back upon adsorption of the pentacene monolayer; this push-back (pillow effect) leads to a significant work-function decrease for the modified gold surface. The electronic couplings between the highest occupied molecular orbital of pentacene and the Au(1 1 1) surface and between adjacent pentacene molecules within the monolayer, were extracted from the calculated band structures; the pentacene–gold surface electronic coupling is found to be about five times smaller than the electronic coupling between pentacene molecules. 相似文献
56.
Dynamic restoration algorithms which support real-time and multi-services recovery are significant for the survivability of
WDM (wavelength division multiplexed) networks. In this article, an intelligent dynamic restoration algorithm for multi-services
in WDM networks based on the partheno genetic algorithm is proposed. In these networks, partial wavelength conversion is used.
The algorithm is implemented within an interconnected multilayer-graph model and two kinds of optical networks matrix models.
Compared with the basic restoration scheme, the proposed algorithm can make use of available network state information and
can restore the affected multi-services fast and parallel. Simulation showed that the proposed algorithm can improve the restoration
efficiency under high loads and reduce the service disruption ratio on the basis of fully utilizing resources of the network.
相似文献
Na ZhuEmail: |
57.
Qifeng Han Chenghong Duan Changjian Ji Kai Qiu Fei Zhong Xinhua Li Zhijun Yin Xiancun Cao Xiuju Zhou Yuqi Wang 《Journal of Electronic Materials》2008,37(8):1058-1063
Self-seeded aluminum nitride (AlN) crystals were successfully grown in a tungsten crucible by the sublimation method. The
polarities along the growth direction of these AlN samples were characterized by chemical etching, combined with high-resolution
transmission electronic microscopy (HRTEM) and Raman spectroscopy. It has been proven by our experimental results that etching
in KOH solution and in molten KOH-NaOH can be a reliable method to determine the surfaces with different polarities. Chemically
active N-polar (0001) AlN surfaces were removed appreciably, while only etch pits related to threading dislocations were observed
on Al-polar surfaces after chemical etching. HRTEM images revealed that there are noticeable inversion domain boundaries in
the samples. Raman spectrum measurements showed the vibration mode change before and after etching in the same geometrical
arrangement. 相似文献
58.
近年来,计算机技术在竞技体育中应用的范围越来越广。运动员在训练中采用先进的科学技术可以提高其训练的效果。本文阐述了三维人体运动的计算机辅助分析在体育中的应用,包括三维人体运动的定义,分析了基于骨骼蒙皮法构建运动员模型,最后阐述了运动数据的预处理、提取和分析。 相似文献
59.
电力宽带的改进措施与拓展应用 总被引:1,自引:0,他引:1
随着互联网业务的快速增长,宽带技术应用日益广泛.本文通过对电力载波宽带技术(PLC)的进一步分析,给出了干扰的成因和对抗的措施,研究了通信新技术(如FDM、ATM等)在PLc中的作用,提出了电力宽带的拓展运用模式. 相似文献
60.
A Green's function approach to the analysis of semiconductor lasers is formulated in a form suitable for complex cavity structures. Both the spontaneous emission rate and the effective phase-amplitude coupling factor can be accurately evaluated. For distributed-feedback (DFB) lasers, the spontaneous emission rate is strongly dependent on both the facet reflectivities and the grating coupling coefficients. The effective phase-amplitude coupling factor depends on the wavelength detuning from the gain maximum. The calculated linewidth of DFB lasers differs considerably from previous calculated results and gives better agreement with experimental results. For composite-cavity lasers, the frequency dependence of the equivalent reflectivity has a strong impact on the phase-amplitude coupling factor and the spontaneous emission rate. Distributed Bragg reflector (DBR) lasers are investigated as an example of a composite-cavity structure 相似文献