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141.
在GS-221高速摄影测量仪中,测角信息采集与处理速度的快慢是重要性能指标之一。本文讨论了如何在尽可能短的时间内对测角信息进行采集和处理的软件实现方法。 相似文献
142.
In this paper, we develop a tool for evaluating performance of a heterogeneous mobile network under different traffic conditions. The traffic condition is specified in a cluster of seven heterogeneous base stations, and “wrap-up” cell structure is applied to account for the traffic that crosses the boundary of the cluster. The performance of the network is specified in metrics which can be computed using the algorithm developed. These metrics relate to call rejection, i.e. the blocking of new calls, and the termination of handoff calls, as well as the carried traffic i.e. the expected number of ongoing calls in a station. These metrics are either measured for a single base station in a cluster, or measured for the average over the whole cluster. We apply the algorithm to some hypothetical data and present the numerical results. We also consider approximating a heterogeneous model with a simpler homogeneous model. Through some numerical results, we demonstrate the magnitude of errors that could result in the approximation. 相似文献
143.
T. Luo C. Yu L.-S. Yan S. Kumar Z. Pan A.E. Willner 《Photonics Technology Letters, IEEE》2006,18(15):1606-1608
We demonstrate a simple optical-fiber-based autocorrelator for picosecond short pulses based on degree-of-polarization measurement while tuning the relative delay of the two orthogonal polarization states of the pulse. The pulsewidths of 20-, 40-, and 80-GHz pulse trains and 2-ps pulses generated by a mode-locked laser are measured. The <-10-dBm optical powers are used in the experiment. The measurement results agree well with the measurements using conventional techniques. Compared with conventional autocorrelators, this technique has the advantages of 1) wavelength independent, 2) significant less alignment, and 3) no high power required. 相似文献
144.
Hydroxyapatite coating on porous silicon substrate obtained by precipitation process 总被引:2,自引:0,他引:2
Chen Shaoqiang Zhu Ziqiang Zhu Jianzhong Zhang Jian Shi Yanling Yu Ke Wang Weiming Wang Xiaohua Feng Xiao Luo Laiqiang Shao Li 《Applied Surface Science》2004,230(1-4):418-424
Hydroxyapatite Ca10(PO4)6(OH)2 (HAP) is known as a bioactive and biocompatible material, HAP coatings were used to improve the biocompatible of substrate by many researcher, In this work, HAP thin films on porous silicon (PS) substrates have been prepared by aqueous precipitation method with rapid thermal annealing (RTA) processes. The HAP films had been prepared under the annealing temperature ranging from 300 to 1000 °C. By the measurement of X-ray diffraction (XRD), it was found that for the crystallinity optimization, the heat-treatment at 850–950 °C for 1 h would be favorable. Atomic force microscopy (AFM) and scanning electron microscope (SEM) measurements reveal a dense and smooth surface of the HAP film, and tightly adherence of the coating on porous silicon substrate after sintered. Thus, by this method, porous silicon could be increased its bioactivity and so that could be used in the biomedical area. 相似文献
145.
Li Taihua An Zhu Luo Zhengming Center for Radiation Physics Institute of Nuclear Science Technology Sichuan Union University Chengdu 《原子与分子物理学报》1997,(1)
MEASUREMENTSOFFeANDCuK-ShelIONIZATIONCROSSSECTIONSBYSLOWELECTRONIMPACTLiTaihuaAnZhuLuoZhengmingCenterforRadiationPhysics,Ins... 相似文献
146.
147.
Examines the use of magnetic fields to functionally stimulate peripheral nerves. All electric fields are induced via a changing magnetic field whose flux is entirely confined within a closed magnetic circuit. Induced electric fields are simulated using a nonlinear boundary element solver. The induced fields are solved using duality theory. The accuracy of these predictions is verified by saline bath experiments. Next, the theory is applied to the stimulation of nerves using small, partially occluded ferrite and laminated vanadium permendur cores. Experiments demonstrate the successful stimulation of peripheral nerves in the African bullfrog with 11 mA, 153 mV excitations. These results offer a new vista of possibilities in the area of functional nerve stimulation. Unlike functional electric stimulation (FES), FMS does not involve any half cell reactions, and thus would not have the commensurate FES restrictions regarding balanced biphasic stimulation, strength duration balances, and oxidation issues, always exercising care that the electrodes remain in the reversible operating regime 相似文献
148.
149.
Gillespie J.K. Fitch R.C. Sewell J. Dettmer R. Via G.D. Crespo A. Jenkins T.J. Luo B. Mehandru R. Kim J. Ren F. Gila B.P. Onstine A.H. Abernathy C.R. Pearton S.J. 《Electron Device Letters, IEEE》2002,23(9):505-507
The low temperature (100°C) deposition of Sc2O3 or MgO layers is found to significantly increase the output power of AlGaN/GaN HEMTs. At 4 GHz, there was a better than 3 dB increase in output power of 0.5×100 μm2 HEMTs for both types of oxide passivation layers. Both Sc2 O3 and MgO produced larger output power increases at 4 GHz than conventional plasma-enhanced chemical vapor deposited (PECVD) SiNx passivation which typically showed ⩽2 dB increase on the same types of devices. The HEMT gain also in general remained linear over a wider input power range with the Sc2O3 or MgO passivation. These films appear promising for reducing the effects of surface states on the DC and RF performance of AlGaN/GaN HEMTs 相似文献
150.
Qun Luo 《Journal of Global Optimization》2006,34(4):589-595
In the paper, by using Ky Fan’s section theorem, we obtain an existence theorem for vector equilibrium problems. Motivated
by the ideas of Kinoshita and McLennan, we introduce the concept of the essential component of the solution set for vector
equilibrium problems, and we prove that there exists at least one essential component of the solution set for every vector
equilibrium problem satisfying some conditions.
Research was partially supported by the Natural Science Foundation of Guangdong Province, P. R. China. 相似文献