轴类零件直径、偏心、圆度等的自动测量中的角度空间谐波分析

为保证轴类零件的加工精度,通常需要在加工过程中对其直径、偏心、圆度等进行实时自动测量,本文提出了一种角度空间谐波分析法,通过圆周方向大于8点的测量,可计算出直径、偏心、圆度等多个参数,计算精度高。     

Correction to Construction of Panoramic Image Mosaics with Global and Local Alignment

International Journal of Computer Vision -     

Recent Development of Cognitive and Neuropsychological Assessment in Asian Countries.

There is a growing trend of research in neuropsychological assessment in Asia: The mean number of published studies increased from 1.8 in the 1980s to 16.0 in 2 recent years. About 40% of the studies reviewed concerned test development or adaptation, with the latter greatly outnumbering the former. To facilitate the test selection for clinical use, 36 clinical measures were evaluated based on some statistical criteria. The results showed that only 8 neuropsychological tests (5 Chinese. 2 Korean, and 1 Japanese) met the criteria. Given that Asian and Western populations differ on certain cognitive processes, future development of neuropsychological assessment measures in Asia should move from the adaptation of Western tests toward the construction of original tests with better ecological validity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adrenergic regulation of aqueous outflow

Epinephrine increased outflow facility and cyclic AMP in the in vitro perfused human anterior segment with a maximal facility increase of 44% occurring at approximately 2 x 10(-5) M. Cyclic AMP measured in the perfusate from anterior segments increased by 12-14 fold after administration of 10(-5) M epinephrine. Both the facility increase and cyclic AMP rise were blocked by the beta-2 selective antagonist, ICI118,551. While there was a correlation between the facility increase and elevation in cyclic AMP levels, the rise in cyclic AMP preceded the facility increase by about 1 hour, suggesting that the ultimate effect of epinephrine involved a rather slow event such as synthesis and release of prostaglandins or protein synthesis. Subsequent perfusion studies showed that very large concentrations of indomethacin were necessary to block the outflow facility effect of epinephrine, suggesting that prostaglandin synthesis did not underlie the facility effect in this system. However, 5 x 10(-5) M cyclohexamide blocked the effect on outflow facility of both epinephrine and forskolin, but did not block the rise in cyclic AMP. These studies suggest that protein synthesis may play a role in the epinephrine-induced facility increase at some point beyond the second messenger level.     

Systems and Experiment Paper: Construction of Panoramic Image Mosaics with Global and Local Alignment

This paper presents a complete system for constructing panoramic image mosaics from sequences of images. Our mosaic representation associates a transformation matrix with each input image, rather than explicitly projecting all of the images onto a common surface (e.g., a cylinder). In particular, to construct a full view panorama, we introduce a rotational mosaic representation that associates a rotation matrix (and optionally a focal length) with each input image. A patch-based alignment algorithm is developed to quickly align two images given motion models. Techniques for estimating and refining camera focal lengths are also presented.In order to reduce accumulated registration errors, we apply global alignment (block adjustment) to the whole sequence of images, which results in an optimally registered image mosaic. To compensate for small amounts of motion parallax introduced by translations of the camera and other unmodeled distortions, we use a local alignment (deghosting) technique which warps each image based on the results of pairwise local image registrations. By combining both global and local alignment, we significantly improve the quality of our image mosaics, thereby enabling the creation of full view panoramic mosaics with hand-held cameras.We also present an inverse texture mapping algorithm for efficiently extracting environment maps from our panoramic image mosaics. By mapping the mosaic onto an arbitrary texture-mapped polyhedron surrounding the origin, we can explore the virtual environment using standard 3D graphics viewers and hardware without requiring special-purpose players.An erratum to this article can be found at     

Realistic rendering and animation of knitwear

We present a framework for knitwear modeling and rendering that accounts for characteristics that are particular to knitted fabrics. We first describe a model for animation that considers knitwear features and their effects on knitwear shape and interaction. With the computed free-form knitwear configurations, we present an efficient procedure for realistic synthesis based on the observation that a single cross section of yarn can serve as the basic primitive for modeling entire articles of knitwear. This primitive, called the lumislice, describes radiance from a yarn cross section that accounts for fine-level interactions among yarn fibers. By representing yarn as a sequence of identical but rotated cross sections, the lumislice can effectively propagate local microstructure over arbitrary stitch patterns and knitwear shapes. The lumislice accommodates varying levels of detail, allows for soft shadow generation, and capitalizes on hardware-assisted transparency blending. These modeling and rendering techniques together form a complete approach for generating realistic knitwear.     

用于去除单张图像高光的光照约束补色

在计算机视觉研究领域,如何检测和消除图像中的高光(specular)一直是个热点问题,有关的研究结果对于提高计算机视觉算法性能有着重要的影响.针对这一问题,提出了一种检测和消除高光的方法.首先,通过比较高光和漫反射光(diffuse)的色度特性的不同,给出了一种交互检测单色物体表面高光区域的方法;然后,引入补色(inpainting)方法并结合光照约束条件,设计了一种去除单张图像中高光并还原出漫反射分量的新的补色算法.与一般补色方法不同,该算法充分利用了高光区域含有的信息来指导补色过程.通过综合利用观测到的像素值、光源的色度分析(illumination chromaticity analysis)、光源颜色的平滑性等来约束补色过程,保证了算法能够克服一般的补色方法无法保持物体表面细微明暗变化的缺点.实验结果表明,与以往的去除单张图像高光的方法相比,该算法能够提供更好的光源色度估计,从而得到更准确的结果.     

Gas marbles: ultra-long-lasting and ultra-robust bubbles formed by particle stabilization

Bubbles and foams are ubiquitous in daily life and industrial processes. Studying their dynamic behaviors is of key importance for foam manufacturing processes in food packaging, cosmetics and pharmaceuticals. Bare bubbles are inherently fragile and transient; enhancing their robustness and shelf lives is an ongoing challenge. Their rupture can be attributed to liquid evaporation, thin film drainage and the nuclei of environmental dust. Inspired by particle-stabilized interfaces in Pickering emulsions, armored bubbles and liquid marble, bubbles are protected by an enclosed particle-entrapping liquid thin film, and the resultant soft object is termed gas marble. The gas marble exhibits mechanical strength orders of magnitude higher than that of soap bubbles when subjected to overpressure and underpressure, owing to the compact particle monolayer straddling the surface liquid film. By using a water-absorbent glycerol solution, the resulting gas marble can persist for 465 d in normal atmospheric settings. This particle-stabilizing approach not only has practical implications for foam manufacturing processes but also can inspire the new design and fabrication of functional biomaterials and biomedicines.     

切牙牙体、牙周膜的应力分析

本文应用有限单元法,从生物力学的角度,揭示切牙在外力作用下,牙体、牙周膜内部的应力分布,从而为分析牙齿、牙周膜损伤,引起临床病变,提供理论依据。