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131.
运动物体位置跟踪系统可用工作在红外波段的激光 ,测量“调制光波”往返于被测距离上相位差的方法来测定距离。利用 DSP鉴相技术 ,通过快速傅立叶变换软件可快速实时测量运动物体的距离及其运行速度。该系统能极其准确地显示运动物体的实际位置 ,实现对运动物体速度的数字化控制。 相似文献
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从特定消谐的原理出发,建立了产生谐波的数学模型,分析了开关角与各次谐波之间的关系,得到产生谐波不宜采用查表法而应实时计算的结论.对于特定消谐式逆变器的实时控制,进行了硬件和软件方面的设计,并举例分析了实验结果. 相似文献
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XU Dachuan~ HAN Jiye~ & DU Dongle~ . College of Applied Sciences Beijing University of Technology Beijing China . Institute of Applied Mathematics Academy of Mathematics Systems Science Chinese Academy of Sciences Beijing China . Faculty of Administration University of New Brunswick P.O.Box Fredericton NB EB A Canada 《中国科学A辑(英文版)》2005,48(9)
We develop improved approximation algorithms for two NP-hard problems: the dense-n/2-subgraph and table compression.Based on SDP relaxation and advanced rounding techniques,we first propose 0. 5982 and 0. 5970-approximation algorithms respec- tively for the dense-n/2-subgraph problem (DSP) and the table compression problem (TCP). Then we improve these bounds to 0. 6243 and 0. 6708 respectively for DSP and TCP by adding triangle inequalities to strengthen the SDP relaxation.The results for TCP beat the 0. 5 bound of a simple greedy algorithm on this problem,and hence answer an open question of Anderson in an affirmative way. 相似文献
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基于DSP的嵌入式导航计算机分布式系统设计 总被引:4,自引:3,他引:4
为满足MIMU/GPS组合导航系统的小型化、低功耗、低成本等条件,以及越来越高的精度要求,以TI公司TMS320VC5402型DSP器件为核心,设计了一种嵌入式导航计算机分布式系统。此设计可提高系统的精度,更好地满足系统实时性要求。 相似文献
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S. Cint Pinzaru Cs. Müller I. S. Tdor B. Glamuzina V. Chis 《Journal of Raman spectroscopy : JRS》2016,47(6):636-642
Commercially available diarrhetic shellfish poisoning (DSP) marine toxins are limited to micrograms samples invisible to the naked eye or in small amounts of micromole concentration solutions that are not suitable for normal Raman spectroscopy. As the Raman‐derived techniques are increasingly employed in various detection schemes of harmful substances, Raman spectra of the target compounds are essential for molecular recognition, detection and sensing reasons. Using a new μ‐RIM™ stainless steel hydrophobic substrate, we recorded near‐infrared micro‐Raman spectrum of okadaic acid (OA), a DSP marine biotoxin from 75 µg recrystallized toxin after drop coating deposition. Excitation with the 785‐nm line allowed the recovery and assembling of the Raman spectrum over the 100–3200 cm−1 spectral range on several OA microparticles, while the 532‐nm line excited the fluorescence emission that hampered the Raman signal. Density functional theory calculations were conducted on the isolated species both in gas phase and in ethanol solution to accurately assess and interpret the experimentally observed Raman bands. A good correlation between the experimental and theoretical Raman bands allowed for a reliable vibrational Raman assignment. Owing to the molecular geometry with intramolecular hydrogen bonds, the CC conjugated systems together with the methyl groups exhibited dominant OA Raman bands. Unlike domoic acid, an amnesic shellfish poisoning toxin whose carboxyl group showed the most intense Raman band, OA Raman characteristic band was not assigned to carboxyl group. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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