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91.
[Correction Notice: An erratum for this article was reported in Vol 23(2) of Psychological Assessment (see record 2011-09525-001). There was an omission in the author note. The author note should have included a disclosure as follows, “Russell A. Barkley receives royalties for books, videos, and rating scales from Guilford Publications, and is the author of Barkley Adult ADHD Rating Scale-IV (BAARS-IV), Barkley Deficits in Executive Functioning Scale (BDEFS), and Barkley Functional Impairment Scale (BFIS), all published by Guilford Press.”] Experts recommend that clinicians evaluating adults for attention-deficit/hyperactivity disorder (ADHD) obtain information from others who know the patient well. The authors examined correspondence between the self- and other-ratings of ADHD symptoms and impairment using 3 groups of adults recruited on the basis of their severity of ADHD: ADHD diagnosis (n = 146), clinical controls self-referring for ADHD but not diagnosed (n = 97), and community controls (n = 109). The influences of diagnostic group, informant relationship, sex of participant, IQ, and comorbid anxiety and depression on self-informant disparities were also examined. Results indicated moderate to high agreement (.59–.80) between self and others on current functioning and slightly lower levels (.53–.75) between self- and parent ratings of childhood functioning. Examination of difference scores between self- and other ratings revealed small mean disparities (?0.1 to +5.0 points) but substantial variation (SDs = –2.4 to 8.9 points) for both current and childhood ratings. Clinic referrals not diagnosed with ADHD, particularly women, had higher disparities than was evident in the ADHD and community groups. Age, IQ, and education were not associated with disparities in most ratings. Higher anxiety, in contrast, was associated with greater disparities on all current and childhood measures of both ADHD and impairment. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
92.
基于运动和视差信息的立体视频质量客观评价   总被引:3,自引:3,他引:0  
在研究人类 立体视觉特性及现有立体图像/视频质量评价算法的基础上,提出了一种基于运动信息和视 差信息的立 体视频质量的客观评价方法。方法包括视频质量评价(VQA)和视频立体感评价(VSSA)两个指 标,其中VQA的估计基于梯度的结构相似度(GSSIM) 算法,并充分考虑了帧内的亮度信息和结构信息、帧间运动信息以及人眼的感知特性对视频 质量的影响, 特别是根据人类的视觉特性,对左右视点的质量赋予了不同的权重;VSSA的估计 是通过计算参考 视频的绝对差值图和降质视频的绝对差值图之间的峰值信噪比(PSNR)而得到。实验结果表明,本文方法对基于H.264 编码的失真视频的评价结果与主观测试有较高的一致性,很好地体现人眼的视觉特性。  相似文献   
93.
The WHO Housing and health guidelines recommend a minimum indoor temperature of 18°C to prevent cold-related diseases. In Japan, indoor temperatures appear lower than in Euro-American countries because of low insulation standards and use of partial intermittent heating. This study investigated the actual status of indoor temperatures in Japan and the common characteristics of residents who live in cold homes. We conducted a nationwide real-world survey on indoor temperature for 2 weeks in winter. Cross-sectional analyses involving 2190 houses showed that average living room, changing room, and bedroom temperatures were 16.8°C, 13.0°C, and 12.8°C, respectively. Comparison of average living room temperature between prefectures revealed a maximum difference of 6.7°C (Hokkaido: 19.8°C, Kagawa: 13.1°C). Compared to the high-income group, the odds ratio for living room temperature falling below 18°C was 1.38 (95% CI: 1.04-1.84) and 2.07 (95% CI: 1.28-3.33) for the middle- and low-income groups. The odds ratio was 1.96 (95% CI: 1.19-3.22) for single-person households, compared to households living with housemates. Furthermore, lower room temperature was correlated with local heating device use and a larger amount of clothes. These results will be useful in the development of prevention strategies for residents who live in cold homes.  相似文献   
94.
一种用于焊接工件三维重建的视差图分割算法   总被引:1,自引:1,他引:0       下载免费PDF全文
王军  梁志敏  高洪明 《焊接学报》2009,30(11):101-104
在遥控焊接中采用立体视觉传感建立焊接工件的三维模型时,视差图的分割是重要步骤之一.文中对经典USF平面距离图分割算法进行改进,通过增加区域合并步骤,使之能够分割含有圆柱面的立体视差图.区域合并步骤分为边界探测和合并曲面两步.在边界探测步骤记录平面分割所得区域的边界像素;合并曲面步骤通过比较相邻区域的边界像素间的法向量夹角和距离,判断相邻区域是否属于同一曲面,并将属于同一曲面的区域赋予相同的标签.文中给出了马鞍形工件的立体视差图分割结果,证明了算法的可行性.
Abstract:
In remote welding, the segmentation of disparity map is an important step to create 3D model of weld workpiece by stereo vision sensor. In this paper, the USF plane range image segmentation algorithm was introduced into disparity map segmentation, and by a region combination step, the revised algorithm can deal with the disparity map containing cylinder surface. The combination step could be divided into boundary detecting and curve region relabeling. During boundary detection, the pixel at the boundary of the segmented region after plane segmentation was recorded. In curve region relabehng, the adjacent regions in the same curved surface were assigned with the same label by comparing the boundary pixels' normal direction and distance between them. A segmented result of disparity map of saddle workpiece is shown to prove the feasibility of the algorithm.  相似文献   
95.
王翀  赵力  齐增义  罗琳 《信号处理》2010,26(3):347-353
本文提出了一种新颖的基于改进BP算法的中间视合成方法。方法中首先改进了BP(Belief Propagation)算法来提高视差估计的正确率,然后在视图插值中设计了新的插值策略,在区域分类的基础上有针对地进行中间视合成。实验结果表明,采用本文提出的中间视合成方法可以获得具有很好视觉效果的虚拟视图。   相似文献   
96.
轴承行业热处理装备技术水平分析及对策探讨   总被引:2,自引:0,他引:2  
张伟 《热处理》2001,16(4):5-11
综述了国内外轴承行业在退火、淬火回火、渗碳和感应加热等热处理装备方面的现状和存在的差距,提出了改变我国轴承热处理落后面貌的对策。  相似文献   
97.
A variational h‐adaptive finite element formulation is proposed. The distinguishing feature of this method is that mesh refinement and coarsening are governed by the same minimization principle characterizing the underlying physical problem. Hence, no error estimates are invoked at any stage of the adaption procedure. As a consequence, linearity of the problem and a corresponding Hilbert‐space functional framework are not required and the proposed formulation can be applied to highly non‐linear phenomena. The basic strategy is to refine (respectively, unrefine) the spatial discretization locally if such refinement (respectively, unrefinement) results in a sufficiently large reduction (respectively, sufficiently small increase) in the energy. This strategy leads to an adaption algorithm having O(N) complexity. Local refinement is effected by edge‐bisection and local unrefinement by the deletion of terminal vertices. Dissipation is accounted for within a time‐discretized variational framework resulting in an incremental potential energy. In addition, the entire hierarchy of successive refinements is stored and the internal state of parent elements is updated so that no mesh‐transfer operator is required upon unrefinement. The versatility and robustness of the resulting variational adaptive finite element formulation is illustrated by means of selected numerical examples. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
98.
Traditional methods of constructing virtual environ-ment are based on3D geometry models.Although ithas the advantage of easy interaction,it has the prob-lem of complex modeling and slowdisplaying.RecentlyImage Based Rendering(IBR)method has been pro-duced,which models the environment using pieces ofimages.In this method requiring time does not rely onthe environmentcomplexity,butithas the disadvantageof difficult interaction.In order to take advantage oftheir merits concurrently,a method bl…  相似文献   
99.
基于图割的图像匹配算法   总被引:11,自引:0,他引:11  
王年  范益政  鲍文霞  韦穗  梁栋 《电子学报》2006,34(2):232-236
用标号表示视差,建立能量函数,把匹配问题转化为能量函数最小化问题;通过构造网络,使能量与网络的割的容量相联系;利用图的网络流理论给出能量函数的最小化,从而获得图像匹配的视差数据.与目前已有基于图割的匹配算法相比,本算法将标号从1维向量推广到2维向量,适用于更一般情形下的视觉匹配,并且在全局上获得能量函数最小.实验结果表明,所提的匹配算法准确率较高.  相似文献   
100.
基于对应点匹配的物体深度信息测量   总被引:4,自引:0,他引:4  
提出了一种基于对应点匹配的物体深度信息测量方法。首先给出了物理图像坐标系与像素坐标系之间的关系;其次,借助于相关法计算两幅图像中目标的相似度,以实现同一目标在不同成像中的匹配;然后从目标几何形状的角点出发,结合对应点的外极线约束条件,提出一种有效的对应点匹配算法,并利用对应点的视差计算基于光轴平行的双摄像机成像的目标深度信息。计算机仿真结果验证了算法的有效性。  相似文献   
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