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101.
通过与其它传感技术的对比,简要分析了激光视觉在焊接生产中得到成功应用的原因。分析了早期激光视觉系统的特征和当时面临的挑战。介绍了Servo-Robot激光视觉的关键技术和已取得的显著进步,阐述了集成激光视觉的移动式便携焊接机器人和激光视觉在焊缝质量检测中的应用。展望了激光视觉系统的未来和智能视觉在提高机器人性能方面发展的显著进步,包括改进机器人人工示教、离线编程及视觉辅助机器人示教。 相似文献
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Zdenek Nejedlý John L. Campbell Jeff Brook Robert Vet Robert Eldred 《Aerosol science and technology》2013,47(1):96-108
The GAViM program provides fine particulate and visibility data for several remote locations in Canada. Two long-term intercomparison studies between the GAViM and a major U.S. aerosol monitoring network, IMPROVE, were used to evaluate the uncertainty in the analytical data produced by proton induced x-ray emission (PIXE), proton elastic scattering analysis (PESA), and gravimetric analysis. GAViM and IMPROVE agreed well for elements from Fe to Zn where PIXE is the most sensitive; the relative difference between the 2 networks for Fe and Zn was <2%. Some lighter elements, e.g., sodium or sulphur, revealed a difference of 10-20%. Furthermore, an empiric conversion scheme for the GAViM absorption data produced by the laser integrated plate method (LIPM) was derived from the comparison to the IMPROVE thermal/optical reflectance (TOR) data. This conversion depends on the aerosol composition and is therefore site specific. It allows estimation of the elemental carbon concentrations from the historic raw light absorption values obtained by LIPM. If the mass attenuation coefficient of the fine aerosol collected at the 2 remote GAViM sites is assumed to be equal to 10 m 2 /g, then the results imply that the light absorption coefficient measured by LIPM is generally higher than the true value by up to a factor of 1.3 or 1.8, respectively. In both cases, LIPM overestimated the black carbon content, mostly for the lightly loaded samples. 相似文献
104.
Wyman Peter A.; Brown C. Hendricks; Inman Jeff; Cross Wendi; Schmeelk-Cone Karen; Guo Jing; Pena Juan B. 《Canadian Metallurgical Quarterly》2008,76(1):104
Gatekeeper-training programs, designed to increase identification and referral of suicidal individuals, are widespread but largely untested. A group-based randomized trial with 32 schools examined impact of Question, Persuade, Refer (QPR) training on a stratified random sample of 249 staff with 1-year average follow-up. To test QPR impact, the authors introduced and contrasted 2 models of gatekeeper-training effects in a population: gatekeeper surveillance and gatekeeper communication. Intent-to-treat analyses showed that training increased self-reported knowledge (effect size [ES] = 0.41), appraisals of efficacy (ES = 1.22), and service access (ES = 1.07). Training effects varied dramatically. Appraisals increased most for staff with lowest baseline appraisals, and suicide identification behaviors increased most for staff already communicating with students about suicide and distress. Consistent with the communication model, increased knowledge and appraisals were not sufficient to increase suicide identification behaviors. Also consistent with the communication model were results from 2,059 8th and 10th graders surveyed showing that fewer students with prior suicide attempts endorsed talking to adults about distress. Skill training for staff serving as "natural gatekeepers" plus interventions that modify students' help-seeking behaviors are recommended to supplement universal gatekeeper training. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
Greenberg Jeff; Pyszczynski Tom; Solomon Sheldon; Rosenblatt Abram; Veeder Mitchell; Kirkland Shari; Lyon Deborah 《Canadian Metallurgical Quarterly》1990,58(2):308
Three experiments were conducted to test the hypothesis, derived from terror management theory, that reminding people of their mortality increases attraction to those who consensually validate their beliefs and decreases attraction to those who threaten their beliefs. In Study 1, subjects with a Christian religious background were asked to form impressions of Christian and Jewish target persons. Before doing so, mortality was made salient to half of the subjects. In support of predictions, mortality salience led to more positive evaluations of the in-group member (the Christian) and more negative evaluations of the out-group member (the Jew). In Study 2, mortality salience led to especially negative evaluations of an attitudinally dissimilar other, but only among subjects high in authoritarianism. In Study 3, mortality salience led to especially positive reactions to someone who directly praised subjects' cultural worldviews and especially negative reactions to someone who criticized them. The implications of these findings for understanding in-group favoritism, prejudice, and intolerance of deviance are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
The author describes the process that led him to run for election to the Arizona State House of Representatives. His decision was more the result of an interest in the political process and a commitment to the principles of the democratic process than simply a belief that he could effect major changes in the delivery of mental health care to Arizona's citizens. He is now 1 voice out of the 91 in the Arizona State House of Representatives, not 1 voice in about 5 million residents of the state. His training as a psychologist, including training in the scientific method, has helped him become a better representative. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Research has demonstrated that oral reading fluency probes are reliable and valid for indexing reading achievement. If these probes are to be used for decision making, bias must be examined for various factors, including ethnicity, gender, language background, and socioeconomic status. Data from nearly 4,000 Caucasian and Hispanic students in grades one through three were used to examine potential bias in oral reading fluency scores predicting Stanford Achievement Test-Ninth Edition (SAT-9; Harcourt Brace & Co., 1997a, 1997b) Total Reading scores. Using a series of hierarchical multiple regression models, bias was first examined using concurrent SAT-9 scores as the criterion and then examined using subsequent SAT-9 scores as the criterion. The results reveal that it is the combination of factors, not any one in isolation, that significantly contributes to intercept bias findings. Overall, home language emerged as the strongest factor influencing bias in the prediction of SAT-9 scores from oral reading fluency scores. The implications of these findings are discussed as related to current and proposed uses of oral reading fluency probes. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
109.
Stice Eric; Rohde Paul; Seeley John R.; Gau Jeff M. 《Canadian Metallurgical Quarterly》2008,76(4):595
In this depression prevention trial, 341 high-risk adolescents (mean age = 15.6 years, SD = 1.2) with elevated depressive symptoms were randomized to a brief group cognitive-behavioral (CB) intervention, group supportive-expressive intervention, bibliotherapy, or assessment-only control condition. CB participants showed significantly greater reductions in depressive symptoms than did supportive-expressive, bibliotherapy, and assessment-only participants at posttest, though only the difference compared with assessment controls was significant at 6-month follow-up. CB participants showed significantly greater improvements in social adjustment and reductions in substance use at posttest and 6-month follow-up than did participants in all 3 other conditions. Supportive-expressive and bibliotherapy participants showed greater reductions in depressive symptoms than did assessment-only controls at certain follow-up assessments but produced no effects for social adjustment and substance use. CB, supportive-expressive, and bibliotherapy participants showed a significantly lower risk for major depression onset over the 6-month follow-up than did assessment-only controls. The evidence that this brief CB intervention reduced risk for future depression onset and outperformed alternative interventions for certain ecologically important outcomes suggests that this intervention may have clinical utility. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.