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991.
Sun Wei Wang Cong Bu Dexu Liu Shengnan Wu Baoqiang Ouyang Minghua 《International Journal of Control, Automation and Systems》2012,10(2):430-436
This paper presents a novel online learning visual servo controller integrating the FCMAC with proportion controller for the
control of position of manipulator end-effector. Since the FCMAC has good learning capability and fast learning speed, and
can save much computer memory space by fuzzy processing of input space division and memory unit activation, it is used to
develop an adaptive control law by learning the relationship between the image feature errors and manipulator input, and the
aim of online learning of the FCMAC is to minimize the output of proportion controller. Furthermore, the FCMAC has no need
for models of robot manipulator and image feature extraction, so that the capability of proposed controller for tasks under
uncertain environment can be improved. Finally, the proposed controller is proved to be effective by the experiment, and compared
with BP neural network. 相似文献
992.
Jinguang Han Willy Susilo Yi Mu Jun Yan 《International Journal of Information Security》2012,11(6):389-401
Oblivious signature-based envelope (OSBE) schemes have demonstrated their potential applications in the protection of users privacy and rights. In an OSBE protocol, an encrypted message can only be decrypted by the receiver who holds a valid signature on a public message, while the sender (encrypter) does not know whether the receiver has the signature or not. Our major contributions in this work lie in the following aspects. We improve the notion of OSBE so that a valid credential holder cannot share his/her credential with other users (i.e., all-or-nothing non-transferability). We clarify the relationship between one-round OSBE and identity-based encryption (IBE) and show that one-round OSBE and semantically secure IBE against the adaptively chosen identity attack (IND-ID-CPA) are equivalent, if the signature in the OSBE scheme is existentially unforgeable against adaptively chosen message attacks. We propose an oblivious access control scheme to protect user privacy without the aid of any zero-knowledge proof. Finally, we also highlight some other novel applications of OSBE, such as attributed-based encryption. 相似文献
993.
994.
支持向量机是一类新型机器学习方法,成功应用于各个领域,算法在分类性能上优于其它学习算法。该文在字符特征提取基础上,将支持向量机理论应用于车牌识别系统,提高识别率和识别速度,具有很好的推广价值。 相似文献
995.
杜 《数码设计:surface》2012,(7):97-99
张爱玲是现代中国自称为"恋衣狂"的仙才作家。她不仅是我国服装文化的研究者,也是身体力行的实践者。她中西交融、化俗为雅、参差对照、猎求奇异和贵族化情结的服装设计艺术,与她的小说《传奇》一样,已成为人们永远讲不完的神话故事。 相似文献
996.
997.
A method of compensating for the lag of the video cameras typically used in angiographic systems is presented for use in sequences of digitized X-ray images. The lag effect is reduced by a straightforward weighted subtraction, which has the undesirable side effect of increasing noise. By superimposing several lag-corrected and appropriately shifted images, however, the signal-to-noise ratio can be restored. The algorithm uses the phase-correlation method to measure the two-dimensional shift of a mobile coronary arterial structure. Processing is confined to a rectangular area of interest (AOI), which encloses a feature of clinical significance. The differences of the phases of the Fourier transforms of two frames is computed, combined with an appropriate filter, and inverse Fourier-transformed to produce a phase-correlation image. The vector separation from the origin of image space of the peak of the phase-correlation image is the estimate of the shift of the artery's position in the second frame as compared to the first. The isolation of the AOI from the surrounding image is achieved by the application of a window and correction for any linear trend in the background intensity. 相似文献
998.
福禄宫位于湖南长沙市城西区,始建于清代光绪年间。解放后,福禄宫因未及时修理维护,朽损情况严重,1983年底被拆毁。通过对残留木制装修构件拼凑,推算出该建筑的蝼蜂窠部分测绘图。福禄宫蝼蜂窠类似于北方斗栱中的平身科,是一种装饰性构件。福禄宫的昂嘴采用翼龙飞凤交错排列的形式,部分昂嘴端部另加雕饰花板。蝼蜂窠采用层层叠置出踩的形式,其表面只施以桐油或光油等透明涂料,未施其它色漆及彩绘。 相似文献
999.
1000.
本文介绍一种利用原水中含有的无机盐,加入廉价的化学试剂除去饮用水中微量铀的简便方法。并对其除铀机理进行了探讨,证明除铀主要是以软化水过程中产生的氢氧化镁表面吸附共沉淀机理进行的。 相似文献