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991.
Saleh Al-Takrouri Author Vitae Andrey V. Savkin Author Vitae 《Pattern recognition》2010,43(6):2054-2067
A new approach to texture recognition and inpainting problems is proposed. The approach is based on the robust model validation and state estimation techniques. The proposed solutions require the modeling of textures by using uncertain dynamical systems. We propose a new modeling method which is efficient in terms of computational and memory requirements. The main aspects of the modeling method include system identification and order reduction of marginally stable uncertain discrete-time systems. To demonstrate the results, both static-image textures and video textures (also known as dynamic textures) are considered. 相似文献
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994.
Ákos Zarándy Csaba Rekeczky 《International Journal of Circuit Theory and Applications》2011,39(10):983-1005
Topographic and non‐topographic image processing architectures and chips, developed within the CNN community recently, are analyzed and compared. It is achieved on a way that the 2D operators are collected to classes according to their implementation methods on the different architectures, and the main implementation parameters of the different operator classes are compared. Based on the results, an efficient architecture selection methodology is formalized. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
995.
本文从"影像"与"建筑"的关系这一角度出发,试图针对朱利斯·舒尔曼和查尔斯·伊姆斯等人的建筑影像控制"展开分析,并由此扩展为对战后美国现代主义建筑的兴起与其自身的"影像"之关系的研究.这一研究将有助于在媒介泛滥的今天重新审视那一段广为人知的历史,帮助人们更加立体地看待美国现代主义成形的历程,从而明晰"影像控制"制造的"... 相似文献
996.
Experimental characterization of sheet metal deformation during electro-hydraulic forming 总被引:1,自引:0,他引:1
Aashish Rohatgi Elizabeth V. Stephens Ayoub Soulami Richard W. Davies Mark T. Smith 《Journal of Materials Processing Technology》2011,211(11):1824-1833
A novel experimental technique, that combines high-speed imaging and digital image correlation techniques, has been developed and applied to investigate the high-rate deformation behavior of aluminum sheet during electro-hydraulic forming (EHF). Aluminum alloy AA5182-O sheets (1 mm thick and ∼152 mm diameter) were EHF deformed by high-energy (up to ∼21 kJ) pressure-pulse and the time-evolution of sheet-displacement, velocity, strain and strain-rate quantified. The data shows that different locations on the sheet undergo unique deformation history that is not apparent from the conventional post-mortem strain measurement (using etched circle/grid pattern) approach. Under the experimental conditions used in this work, the sheets were formed into domes and the maximum strain-rate observed was ∼664/s. Further, this maximum strain-rate was observed at an off-apex location and was ∼2.5 times greater than the maximum strain-rate at the dome apex. The maximum velocity observed was ∼100 m/s and the velocity-time data showed evidence of pressure-wave reverberations during the forming process. We believe that knowledge of such time-evolution of sheet deformation is necessary for a better understanding and accurate modeling of sheet formability that has often been reported to exceed quasi-static forming limits under high-rate forming conditions. 相似文献
997.
The paper presents measurements acquired with Large-Scale Particle Image Velocimetry (LSPIV) during normal flows and floods in the Iowa River (U.S.A). For normal flows, comparison is made with measurements obtained with Acoustic Doppler Current Profilers (ADCP) in order to test LSPIV’s performance and to address concerns potentially affecting the accuracy of the measurements. The historic flood of the Iowa River during the summer of 2008 was captured for testing LSPIV capabilities during extreme flows. Lacking alternative measurements during the flood, the LSPIV measurements are compared to the rating curve extrapolated for high flows using a one-to-one discharge–stage relationship. The comparison reveals limitations of the single-values rating curve for providing discharge estimates during high flows. Finally, the paper summarizes lessons learned during these and previous LSPIV studies with the intent to chart the research needed to enhance this promising non-intrusive field measurement technique. 相似文献
998.
In this paper, a novel colour image encryption algorithm based on chaos has been proposed. We use chaotic system to encrypt the R, G, B components of a colour image at the same time and make these three components affect each other. So the correlations between R, G, B components can be reduced and the security of algorithm is increased. Simulation results show that the proposed algorithm can encrypt colour image effectively and resist various typical attacks. 相似文献
999.
当前户外LED显示屏的图像质量主要靠业内人士进行简单的主观评价,不确定因素多,尚未形成规范的评价标准。本文参考通用的图像质量主观评价方法,针对LED显示屏显示特性,探讨了主观评价中的各个环境因素的控制方法,并定义了一系列主观评价测试图像的类型,能对显示屏的均匀性、对比度、色彩还原性等显示性能进行更规范更全面的评价。 相似文献
1000.
本文通过对乾久美子的几个商店空间设计案例的读解和分析,展现建筑师利用建筑室内表面颜色虚拟人工照明,创造具有趣味性和矛盾性空间的设计手法,以及她在小型商业室内空间设计中的独特思考。 相似文献