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排序方式: 共有8081条查询结果,搜索用时 15 毫秒
41.
Akira Ishizaki Kazuhiko Takasaki Shoji Shimomura Kouichi Masaki Kanji Kitazawa 《Electrical Engineering in Japan》1996,116(5):128-137
Although brushless resolvers have been used widely as angular position transducers, they are expensive due to their intricate construction, involving a rotary transformer to supply the exciting coils wound on the rotor poles with the current. It is shown theoretically in this paper that the resolver without rotary transformer or brushes can be realized by simple construction, which consists of the stator core with both 4-poles exciting windings and 2-poles output ones and the rotor core carrying no windings. In this resolver the rotor core has minimum gap at one side and a maximum gap at another side of the diameter. It is characterized by an outer surface form that makes the fluctuation part of gap permeance very in proportion to cos θ, where θ represents the angular position of a point in the air gap with respect to the origin on the rotor, the point of minimum air gap. The method determining the rotor form to embody the aforementioned gap permeance variation is also shown. It has been confirmed not only by simulation but also experiment that the 2-phase output voltages of a model designed based on the theory have sinusoidal waveforms with very small harmonic contents. Moreover, the rotor position detected by processing the output voltages through the conventional resolver/digital converter was within acceptable engineering accuracy. 相似文献
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43.
Thomas G. Fiske Louis D. Silverstein 《Journal of the Society for Information Display》2006,14(1):101-105
Abstract— A preferred method for determining the grating modulation of a rear‐projection display using a grating image and Fourier analysis is prescribed. This method is insensitive to spatial image noise and is in better correspondence with the response of the human visual system than is the standard technique. This method is not limited to rear‐projection displays and can be applied to any display technology. 相似文献
44.
A new expression of the weights update equation for the affine projection algorithm (APA) is proposed that improves the convergence rate of an adaptive filter,particularly for highly colored input sign... 相似文献
45.
Google地图是Google向全球提供的电子地图服务,包括丰富的地图和黄页资源,特别是局部详细的卫星地图。通过具体分析Google Map不同坐标系下的坐标转换、Web墨卡托投影方式、地图瓦片URL组织结构,系统地研究了Google地图的算法及实现,并在VS2008环境下用C#语言实现了任意缩放系数下指定地图类型URL的合成和对应图片的下载。文中列出了部分程序代码以帮助大家进行后续开发设计,更有效地将Google地图集成到应用系统中。实验证实,该方法能够快速准确地下载指定范围的地图。 相似文献
46.
针对RoboCup中型组足球机器人比赛中光照变化会使颜色发生色彩漂移,影响颜色识别的准确性问题,提出一种基于光照变化补偿的颜色识别方法。该方法首先利用球的历史信息预测球的位置,然后在较小的区域内用基于色调直方图反向投影的方法找到球后,通过球的亮度直方图的变化计算出光照变化率,用于动态补偿颜色查找表。实验表明该方法能提高颜色识别的光照自适应性。 相似文献
47.
Tomoyoshi Shimobaba Takashi Kakue Nobuyuki Masuda Tomoyoshi Ito 《Journal of the Society for Information Display》2012,20(9):533-538
Holographic projection is for laser displays and has the merits of being aberration free, producing high‐contrast images, having the ability of color reconstruction with one spatial light modulator, and so on. In this paper, we propose a zoomable holographic projection without using a zoom lens and verify the proposed method by using numerical simulation. Although such a system can be readily realized to use the features of holography, which is capable of recording a large image exceeding the hologram size, the required calculation is very time consuming. For acceleration, we used shifted Fresnel diffraction for setting different sampling rates on a hologram and projected image. The proposed method can project any zoom‐in and zoom‐out image between zeroth‐order and first‐order lights, and the processing time and required memory for the zoom are constant. 相似文献
48.
Tsukasa Kinjo Naoki Saito Makoto Omodani 《Journal of the Society for Information Display》2012,20(10):559-565
Projected image on a screen is not always vivid enough when it is projected in a bright room. We generally have to choose either vivid image in a dark room or dull image in a bright room. We have suggested a new projection system which can realize high contrast image projection in a bright room. It is consisted of electronic paper screen, projector, and light‐emitting diode room light. The electronic paper (e‐Paper) screen alternates its whole surface white/black with 120 Hz. Room lights are controlled with the same frequency of 120 Hz with the opposite phase as that of the e‐Paper screen. We have confirmed that our new system has achieved higher contrast than the conventional projection system and also enough readability of paper documents in the room simultaneously. We have thus confirmed that our new system can bring an ideal condition, for audience, which can realize a vivid image projection in a bright room. 相似文献
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