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This article quantifies errors arising from various integration methods and from sampling density in the numerical estimation of colorimetric integrals, e.g., tristimulus values. Both data sampling density and various numerical integration method errors will be distinguished. A test is presented to quantify sampling interval requirements for accurate colorimetric calculations for various illuminants. © 1992 John Wiley & Sons, Inc. 相似文献
54.
Assessed the validity of A. Ellis's (1971, 1973, 1981) contention that being religious was negatively correlated with mental health. 28 very religious, 34 atheist, and 33 religiously-neutral individuals seeking consultation were compared on the frequency and number of 8 reported problems. Contrary to Ellis's prediction, there were no significant differences among the groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Cohen Lawrence H.; Burt Charles E.; Bjorck Jeffrey P. 《Canadian Metallurgical Quarterly》1987,23(4):583
A longitudinal design was used to test the effects of life events experienced by young adolescents and their parents. The criteria were the adolescents' depression, anxiety, and self-esteem. The longitudinal analysis revealed a significant effect for the adolescents' controllable, but not uncontrollable, negative events. However, causal analyses revealed that this effect was the result of the significant relation between initial adjustment and the subsequent occurrence of controllable life stress (e.g., school suspension). The longitudinal analysis also revealed the stress-protective role of positive events, but only with respect to girls' self-esteem. There was no longitudinal support for the role of the parents' negative life events. These findings do not support the etiological importance of an accumulation of relatively discrete negative events experienced by early adolescents and their parents, but they do suggest the need (a) to conceptualize (controllable) life stress as a dependent variable in future research on developmental psychopathology; (b) to examine gender differences in early adolescent life stress; and (c) to develop more sophisticated measures of family life stress. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
Multisite microprobes for neural recordings 总被引:1,自引:0,他引:1
Blum N.A. Carkhuff B.G. Charles H.K. Jr. Edwards R.L. Meyer R.A. 《IEEE transactions on bio-medical engineering》1991,38(1):68-74
Multisite, passive microprobes have been developed to allow simultaneous recording of action potential activity from multiple neurons at different locations in the brain. The microprobes were fabricated using standard integrated circuit techniques. The probe is a planar structure that consists of gold electrodes sandwiched between two polyimide dielectric layers and bonded to a molybdenum structural support. Windows in the top dielectric layer expose the electrode sites and bonding pads. In two distinct versions of the probe four or six recordings sites, respectively, of approximately 25 microns 2 are arranged on a dagger-shaped structure which can penetrate the pia. The bonding pads and interconnect wires at the probe head are entirely encapsulated in a tubular fixture that is packed with silicone RTV and sealed with epoxy to protect the interconnections from contact with body fluids. The site impedances at 1 kHz are typically between 2 and 4 M omega. Probe lifetimes for continuous immersion in physiological saline solution, as measured by impedance, have exceeded 750 h. The failure mechanism is believed to be due to moisture and ion absorption in the top dielectric layer. In acute neurophysiological experiments using the four site probes, action potential activity was recorded from physiologically identified neurons in the dorsal column nuclei of anesthetized rat. 相似文献
57.
Wei Yan Matthew Charles Pritchard Chun-Hsien Chen Li Pheng Khoo 《The International Journal of Advanced Manufacturing Technology》2006,29(5-6):616-628
Collaboration with other members of the supply chain is one means by which small and medium sized enterprises (SMEs) can compete
in today’s global business environment. Thus, early stages of the new product development process involve both technical activities,
e.g., product platform definition, and commercial activities, e.g., bidding for contracts. This paper introduces an integrated
collaborative bidding and design system (CBDS) to help SMEs coordinate the two aspects. General sorting was employed for initial
requirements acquisition and platform definition; while a self-organizing map (SOM) neural network was combined with a concurrent
cost-schedule estimation strategy for refinement of design options and bid evaluation/preparation. A case study on cellular
phone design was then applied for illustrating the proposed prototype system. 相似文献
58.
Mou Weimin; Biocca Frank; Owen Charles B.; Tang Arthur; Xiao Fan; Lim Lynette 《Canadian Metallurgical Quarterly》2004,10(4):238
In 3 experiments, the authors investigated spatial updating in augmented reality environments. Participants learned locations of virtual objects on the physical floor. They were turned to appropriate facing directions while blindfolded before making pointing judgments (e.g., "Imagine you are facing X. Point to Y"). Experiments manipulated the angular difference between the learning heading and the imagined heading and between the actual heading and the imagined heading. The effect of actual-imagined on pointing latency was observed for naive users but not for users with brief training or instructions concerning the fact that objects can move with body movements. The results indicated that naive users used an environment-stabilized reference frame to access information arrays, but with experience and instruction the nature of the representation changed from an environment stabilized to a body stabilized reference frame. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Swim Janet K.; Scott Elizabeth D.; Sechrist Gretchen B.; Campbell Bernadette; Stangor Charles 《Canadian Metallurgical Quarterly》2003,84(5):944
Four experiments examined how an actor's intent and the harm experienced by a target influence judgments of prejudice and discrimination. The presence of intent increased the likelihood that participants judged an actor as prejudiced and the actor's behavior as discriminatory. When intent was uncertain, harm influenced judgments of the behavior, which in turn influenced judgments of the actor, and participants were more cautious in their judgments about an actor than an actor's behavior. Harm also played a stronger role in targets' than observers' judgments. Understanding the role of intent and harm on perceptions of prejudice can help explain variations in targets' versus observers', and possibly targets' versus actors', judgments of discrimination and prejudice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献