试析《Paprika》——解读粉川警部的梦境

本文通过粉川警部的三个梦境来阐释动画影片中的部分蒙太奇手法。在该影片中,蒙太奇并不是导演在作品中的"例行公事",而是鲜明风格的体现。不同的运用方式营造着不同的"蒙太奇作用",在该片中主要体现在剪辑和蒙太奇效果上。     

In vivo interactive visualization of four-dimensional blood flow patterns

In this paper we give an overview over a series of experiments to visualize and measure flow fields in the human vascular system with respect to their diagnostic capabilities. The experiments utilize a selection of GPU-based sparse and dense flow visualization algorithms to show the diagnostic opportunities for volumetric cardiovascular phase contrast magnetic resonance imaging data sets. Besides classical hardware accelerated particle and line-based approaches, an extensible tublet-based visualization, a four-dimensional volumetric line integral convolution and a new two-dimensional cutting plane tool for three-dimensional velocity data sets have been implemented. To evaluate the results, several hearts of human subjects have been investigated and a flow phantom was built to artificially simulate distinctive flow features. Our results demonstrate that we are able to provide an interactive tool for cardiovascular diagnostics with complementary hardware accelerated visualizations. Electronic Supplementary Material  The online version of this article () contains supplementary material, which is available to authorized users.

Assessment of drivers' visual perception of information displayed in LED traffic signs at road construction sites

This study investigated drivers' visual perception of information displayed in LED traffic signs under different levels of environmental luminance. Concerning the information displayed, the environmental luminance comprised four luminance contrasts, two arrow types, and three environmental luminances, which were used to identify the visibility of traffic signs at the reading distance. Regarding visible distance, visibility involved reading starting and end points, extent of glare, comfortable distance, and glare distance. According to the study results obtained by using a highly reliable glare assessment method and studying the LED traffic signs, the lower the luminance contrast of traffic signs was the higher glare the participants perceived. A luminance contrast of 6200:2066 cd/m² provided the farthest comfortable and glare distances, enabling drivers to notice the signs comparatively earlier and have sufficient time to react accordingly. Overall, arrow type “<<<” outperformed “←” because the former was easier for drivers to read and created less glare. Regarding environmental luminance, traffic signs displayed in high and medium luminance environments (i.e., extremely sunny and cloudy days, respectively) each featured their own advantage, whereas those displayed in low luminance environments (nights) have to be further improved.     

数据缓存按需同步的设计与应用

数据缓存可以显著提高读取性能,但也需要及时同步以保证数据实时性。数据源变化触发的即时同步是一种通用的解决方案。但是大压力下,数据快速变化导致的频繁同步必然对服务器性能和通信效率产生负面影响。本文介绍的数据缓存按需同步方案根据业务需求定制同步策略,可以在满足实时性指标的基础上改善服务器性能和通信效率。该方案已经成功应用于笔者团队研发的UniBase分布式内存数据库,并在实际项目中证明了其可行性。     

基于干预规则挖掘因果关系与分段干预事件及对比不等式

为揭示亚复杂系统(SCS)在干预下的特殊行为,提出了对比不等式概念,提出并实现了分段干预规则的挖掘算法;通过在亚复杂系统中施加扰动式干预并分析其动力学效应,提出并实现了基于扰动因果关系挖掘算法。在真实数据上的实验表明,分段干预规则发现了传统挖掘方法难以发现的新干预事件,因果挖掘算法发现了传统方法难以发现的因果关系。     

Simultaneous speckle reduction and contrast enhancement for ultrasound images: Wavelet versus Laplacian pyramid

Speckle can be described as random multiplicative noise. It hampers the perception and extraction of fine details in the image. Speckle reduction techniques are applied to ultrasound images in order to reduce the noise level and improve the visual quality for better diagnoses. It is also used as preliminary treatment before segmentation and classification. Several methods have been proposed for speckle reduction in ultrasound images. Multiscale contrast enhancement has proven to be very efficient for x-ray images. A recent study by Dippel et al. doing a comparison, contrast enhancement of radiographs (x-ray and mammography), between the Laplacian pyramid and the wavelet one proves that the Laplacian pyramid method gives a better result than the wavelet one; the filtering aspect was not taken into account. In ultrasound images a strong contrast variation exists which is different from x-ray and mammography. In this paper a wavelet pyramid with simultaneous speckle reduction and contrast enhancement was applied for the first time on ultrasound images with the area of interest and compared to a Laplacian enhancement pyramid. The optimum choice of wavelet bases for ultrasound images is investigated in this study. In order to realize a fair comparison, the same nonlinear modification in both multiscale schemes is used. The comparison proves that the wavelet pyramid gives a much better result than the Laplacian one for simultaneous speckle reduction and contrast enhancement of ultrasound images. The text was submitted by the author in English. Ali Samir Saad, 1964. 1996 PhD in image processing, Polytechnics School of the Engineering University of Nantes, France. 1993 Masters in Electronics. 1990 Masters in Digital Image Processing, Institute of Computer Sciences and Communication University of Rennes, France. 1989 BS in Electrical Engineering, University of Saint-Etienne. Academy of Lyon, France. 1996–2000 Research associate at the National Center for Macromolecular Imaging. Baylor, Houston, Texas. Assistant professor at King Saud University, Dept. of Biomedical Technology. Area of research in medical image processing and analysis, 23 publications, member of the American Association for the Advancement of Sciences. Marquis Who’s Who in the World; Cambridge Blue Book 2006.     

一种结合灰度和边缘信息的局部特征描述算法

针对单一特征引导图像匹配的准确度有限,提出了一种同时使用灰度和边缘信息的特征描述子。该描述子将图像的几何特征与灰度信息结合起来,首先计算每个特征点的灰度对比直方图,然后引入边缘属性以增强边缘的匹配。实验结果表明,该算法由于同时采用灰度信息与边缘信息引导图像匹配,其匹配效果好于单独使用灰度或边缘的图像匹配算法,在一定程度上降低了误匹配率,同时满足旋转和光照不变性,对图像灰度变化和噪声不敏感,具有良好的匹配性能。     

基于结构信息的图像质量评价模型

针对客观数字图像质量评价方法结构相似度（SSIM）算法对严重失真类型的评价值与主观评价（MOS）值之间存在着明显差异的问题,对几种将SSIM算法与人眼视觉系统（HVS）特性相结合的算法基于图像边缘的ESSIM算法、基于空间域频域敏感的HSSIM算法,以及基于信息内容权值的IWSSIM算法进行了比较。从实验数据可知,ESSIM,HSSIM算法的准确性有不同程度的提高,而IWSSIM模型在比较主客观值相关的单调性方面更为稳定。实验结果为今后结构相似度算法的改进提供了依据,指明研究方向。     

Recency effects as a window to generalization: Separating decisional and perceptual sequential effects in category learning.

Accounts of learning and generalization typically focus on factors related to lasting changes in representation (i.e., long-term memory). The authors present evidence that shorter term effects also play a critical role in determining performance and that these recency effects can be subdivided into perceptual and decisional components. Experimental results based on a probabilistic category structure show that the previous stimulus exerts a contrastive effect on the current percept (perceptual recency) and that responses are biased toward or away from the previous feedback, depending on the similarity between successive stimuli (decisional recency). A method for assessing these recency effects is presented that clarifies open questions regarding stimulus generalization and perceptual contrast effects in categorization and in other domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

一次成井技术在杨家坝铁矿采矿中的应用

采用中深孔微差爆破一次形成切割天井,加快采矿强度,确保生产安全。