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901.
Measures of perceptual speed ability have been shown to be an important part of assessment batteries for predicting performance on tasks and jobs that require a high level of speed and accuracy. However, traditional measures of perceptual speed ability sometimes have limited cost-effectiveness because of the requirements for administration and scoring of paper-and-pencil tests. There have also been concerns about the validity of previous computer approaches to administering perceptual speed tests (e.g., see Mead & Drasgow, 1993). The authors developed two sets of computerized perceptual speed tests, with touch-sensitive monitors, that were designed to parallel several paper-and-pencil tests. The reliability and validity of the tests were explored across three empirical studies (N = 167, 160, and 117, respectively). The final study included two criterion tasks with 4.67 and 10 hours of time-on-task practice, respectively. Results indicated that these new measures provide both high levels of reliability and substantial validity for performance on the two skill-learning tasks. Implications for research and application for computerized perceptual speed tests are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
902.
基于高斯映射的CAD网格法向聚类分割方法 总被引:1,自引:0,他引:1
网格模型特征的分割和识别,能够极大地提高复杂机械产品设计中模型重用、模型编辑的效率。由此,提出一种基于高斯映射的法向聚类CAD网格分割方法。对网格模型各面片法向进行高斯映射,建立各单元面片边连接邻域与高斯球面法向的对应关系。对各法向在高斯球面上进行k-means聚类分割,依据法向初始聚类类型和二面角阈值细化分割。将过分割的细小区域进行合并处理,根据各区域邻接矩阵及其类型的相似性进行特征识别和归并处理。本算法能够高效地对复杂机械产品的网格模型进行分割和识别,不受网格疏密的限制。 相似文献
903.
The Addiction Severity Index (ASI) has been extensively used in the United States and Europe as an indicator of the problems of substance abuse patients. Several studies have shown the ASI to be a reliable and valid instrument, but lately doubt has arisen regarding its validity and reliability. The article focuses on a specific scale of the ASI-the Psychiatric Status scale-and its strength in predicting the use of mental health care. A group of 1,027 heroin patients in Rotterdam, the Netherlands, who participated in a methadone program were the subjects. Three indices have been used: the evaluation index, the clinical index, and the composite scores. It appears that no matter which indices are used, the Psychiatric scale does discriminate between those who will have contact with mental health care and those who will not. However, the percentage of false positives is high. None of the indices predicts the intensity and duration of the mental health care treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
904.
Linehan Marsha M.; Comtois Katherine Anne; Brown Milton Z.; Heard Heidi L.; Wagner Amy 《Canadian Metallurgical Quarterly》2006,18(3):303
The authors describe the development of the Suicide Attempt Self-Injury Interview (SASII), an instrument designed to assess the factors involved in nonfatal suicide attempts and intentional self-injury. Using 4 cohorts of participants, authors generated SASII items and evaluated them with factor and content analyses and internal consistency statistics. The final measure was assessed for reliability and validity with collateral measures. The SASII assesses variables related to method, lethality and impulsivity of the act, likelihood of rescue, suicide intent or ambivalence and other motivations, consequences, and habitual self-injury. The SASII was found to have very good interrater reliability and adequate validity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
905.
906.
It seems clear that, for whatever reasons, the dementia of the Alzheimer type patient group (as well as other patient groups) exhibits behavior that is different from the normal control group. G. Storms, T. Dirikx, J. Saerens, S. Verstraeten, and P. P. De Deyn (2003) rightfully argue that the observed behavior (similarity judgments) does not tell us the source (cause) of the differences between the 2 groups. Rather, the focus of the study should be placed more on finding the ways the 2 groups are different. They also point out various methodological problems in some of the previous attempts to characterize the nature of the differences. Further methodological issues in G. Storms et al.'s study are examined. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
907.
Vallerand Robert J.; Blanchard Céline; Mageau Geneviève A.; Koestner Richard; Ratelle Catherine; Léonard Maude; Gagné Marylène; Marsolais Josée 《Canadian Metallurgical Quarterly》2003,85(4):756
Passion is defined as a strong inclination toward an activity that people like, that they find important, and in which they invest time and energy. Two types of passion are proposed: obsessive and harmonious. Obsessive passion (OP) refers to a controlled internalization of an activity in one's identity that creates an internal pressure to engage in the activity that the person likes. Harmonious passion (HP) refers to an autonomous internalization that leads individuals to choose to engage in the activity that they like. HP promotes healthy adaptation whereas OP thwarts it by causing negative affect and rigid persistence. Results from four studies involving more than 900 participants from different populations supported the proposed conceptualization. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
908.
重型数控机床热误差建模及预测方法的研究 总被引:5,自引:0,他引:5
重型数控机床的热误差已经成为影响其加工精度的一个关键问题。针对一台典型的重型落地铣镗床,以机床热误差测量试验为依据,分析该类机床温度场的特点;据此提出一种旨在完成高效温度测点优化的改进系统聚类方法,该方法使用一种兼顾欧氏距离和相关系数的系统聚类准则,可以有效地降低优化后温度测点之间的共线性。基于优化后的温度测点,利用多元线性回归分析,构建了机床的热误差预测模型。现场试验数据表明,该方法可以将热误差预测的均方根误差降低到10μm以下,相较于其他方法有着更高的热误差预测精度,有望在其他重型数控机床的热误差建模和预测研究中得到更大的推广应用。 相似文献
909.
910.
基于ITD模糊熵和GG聚类的滚动轴承故障诊断 总被引:1,自引:0,他引:1
提出了一种本征时间尺度分解模糊熵和GG模糊聚类的滚动轴承故障诊断方法。首先,将滚动轴承的振动信号进行ITD分解,得到若干个固有旋转分量和一个趋势项。然后,将PR分量分别与原始信号进行相关性分析,筛选出前3个含主要特征信息的PR分量,并将筛选的PR分量的模糊熵作为特征向量。最后,将特征向量输入到GG分类器中进行聚类识别。通过模糊熵、样本熵和近似熵对比,实验结果表明模糊熵能更好的表征故障信号的特征信息;通过GG聚类、GK 聚类和FCM聚类对比,实验结果表明GG聚类效果明显优于FCM、GK的聚类效果。因此,实验证明了基于ITD模糊熵和GG聚类的滚动轴承故障诊断方法的有效性和优越性。 相似文献