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31.
在以两幅立体图像对作为立体图像资源的自由立体显示技术中,观看者必须处在显示屏中央法线方向的有限区域内,才能观看到最佳立体效果。文章介绍了一种克服上述限制、扩展显示器立体视角的方法———观看者跟踪法。采用摄像头拍摄人脸,通过对视频图像的处理获取观看者眼睛位置的连续参数。根据参数的动态变化,通过控制系统的处理,进行光栅位置的自动调整,从而解决了立体视角范围受限制的问题。采用单片机进行控制系统的数据处理,实现了实时性的要求。在分析光栅位移控制系统结构的基础上,根据理论计算以及实验验证,得出了人脸位置参数与光栅位移的变化关系,并给出了单片机的程序控制流程。实验表明,文章所提出的方法可以将显示器的立体视角扩大至±30°,系统响应时间小于50ms。 相似文献
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33.
A promising means to reduce the component of railway rolling noise radiated by the track is to increase the damping of the rail. This increases the attenuation with distance of vibrations transmitted along the rail and thereby reduces the noise radiated. To achieve this, a tuned, damped mass-spring absorber system has been designed. To cover a wide range of frequencies, multiple tuning frequencies are used along with a material with a high damping loss factor. Suitable materials have been found from extensive tests on samples and prototypes of the damper have been built and tested, both in the laboratory and in the field. Results are very promising with reductions of the track component of noise of around 6 dB being measured. 相似文献
34.
本文在对电力系统有源无功与谐波补偿的原理进行理论分析的基础上,运用其有关分析结果主要讨论一种电力有源滤波器主电路及变结构非线性控制系统的组成和工作原理,给出了一种变结构滞环电流跟踪控制的思路,通过Pspice软件对单相和三相系统进行了仿真研究,仿真结果证实了该系统及控制方法的正确性与可行性。 相似文献
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The response of CR-39 detector has been obtained precisely for protons, deuterons, tritons, alpha-particles and lithiumions with energies of a few MeV/nucleon. The track etch rates were determined from the growth curves of pit radius and summarized as the response functions. The accuracy of this method is high enough to discriminate among hydrogen isotopes under a certain condition. The correlation between the response and LET with various cut-off energies has also been examined. It was found that LET is not an unique parameter describing the response function adequately for different ions by the same expression. 相似文献
37.
We introduce the notion of n-fold track extensions of a category C by a natural system D and prove that such extensions represent classes in the cohomology of C with coefficients in D introduced by Baues–Wirsching. This generalizes a result of Huebschmann on the cohomology of groups. 相似文献
38.
教育体制的改革逐步的渗透于教育教学的各个领域,而体育教学也不例外《。体育与健康》的新课改中明确了体育改革的方向,而传统的田径教学中存在着很多的问题,需要结合新课改的要求对体育教学方法中的田径教学方法进行改革的深入。对此,本文将从三个方向探讨田径教学方法的改革。 相似文献
39.
V. S. Nadkarni 《Indian Journal of Physics》2009,83(6):805-811
This article describes our attempts since 1996 to systematically design and synthesize monomers and corresponding polymers
for nuclear track detection. So far more than 15 homopolymers/copolymers have been prepared and tested by us for this purpose.
Some of these polymers show better track detection characteristics vis-á-vis commercially available poly allyl diglycol carbonate (PADC) track detectors.
相似文献
40.
E. Skladnik-Sadowska J. Baranowski M. Milanese R. Moroso J. Pouzo M. Sadowski J. Zebrowski 《Radiation measurements》2001,34(1-6):315-318
The paper reports the application of Solid-State Nuclear Track Detectors to study the pulsed plasma-ion streams emitted from plasma-focus (PF) type discharges, which were performed within a low-energy PACO device constructed at Instituto de Fisica Arroyo Seco. The PACO device was operated under static initial gas conditions or with dynamic gas puffing. Studies of the structure of the fast deuteron beams were carried out within an energy range from 80 keV to about 2 MeV. Studies of ion energy and an ion angular distribution were also performed. The measurements showed that the fast deuterons are emitted in many “narrow” micro-beams, as in other larger PF devices. The anisotropy of the deuteron angular distribution was explained by the stochastic character of the formation of local ion sources within the PF discharge column. 相似文献