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1.
An experimental and theoretical analysis of the nonlinear coupling mechanism between the two solitary pulses circulating in a two-color femtosecond laser is presented. Two operation regimes; synchronized; and nonsynchronized; and a hysteresis of the transition between the two regimes are clearly observed; while independent modelocking and tunability of the output pulse trains is found in both regimes. Pulses in the range from 15 to 100 fs are synchronized with a timing jitter below 2 fs. The combined effects of cross-phase modulation and negative group velocity dispersion are shown to be responsible for the strong pulse correlation in the synchronized regime. Our experimental observations are in agreement with numerical simulations, thus confirming the theoretical model  相似文献   
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This research was an investigation of children's performance on a task that requires memory binding. In Experiments 1 and 2, 4-year-olds, 6-year-olds, and adults viewed complex pictures and were tested on memory for isolated parts in the pictures and on the part combinations (combination condition). The results suggested improvement in memory for the combinations between the ages of 4 and 6 years but not in memory for the isolated parts. In Experiments 2 and 3, the authors also examined the developmental relationship between performance in the combination condition and free recall of a naturalistic event, finding preliminary evidence that performance on a memory task that requires binding is positively related to performance in episodic memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Since DeLone and McLean (D&M) developed their model of IS success, there has been much research on the topic of success as well as extensions and tests of their model. Using the technique of a qualitative literature review, this research reviews 180 papers found in the academic literature for the period 1992–2007 dealing with some aspect of IS success. Using the six dimensions of the D&M model – system quality, information quality, service quality, use, user satisfaction, and net benefits – 90 empirical studies were examined and the results summarized. Measures for the six success constructs are described and 15 pairwise associations between the success constructs are analyzed. This work builds on the prior research related to IS success by summarizing the measures applied to the evaluation of IS success and by examining the relationships that comprise the D&M IS success model in both individual and organizational contexts.  相似文献   
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This paper explores the scale and scope of transformations in the environmental planning field, and the factors that may advance or impede their widespread adoption. A conceptual model is offered which examines scope (defined as type, breadth and structure of the transformation), and the scale of its impact (categorized as stakeholder, organizational, institutional or societal) and applies it to the analysis of several cases in Israel where environmental transformations, affecting the way in which planning is conducted, have been adopted. Conclusions include identification of conditions for facilitating and advancing transformations, including knowledge of innovative alternatives, initiative, willingness to adopt new practices, and identification of policy windows that emerge during conflict, reform, or crisis. The fostering of relations between environmental non-government organizations and planning systems and leadership roles are also significant in catalyzing environmental transformation.  相似文献   
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Objective: To examine between-groups differences in the associations between aspects of processing speed assessed with an inspection time task and attention-deficit/hyperactivity disorder (ADHD) symptoms. Research Design: Two groups comprising 34 children with cerebral palsy (CP) and 70 nonaffected peers (control), ages 8–16 years, participated in a prospective correlational study. Measures included a visual inspection time task and the Conners' Parent Rating Scale—Revised: Long Version. Results: Children with CP exhibited significantly slower processing speed and more symptoms of inattention and hyperactivity than controls. Significant associations between inspection time and ADHD symptoms were found only in the control group. Conclusions: Findings have implications for clinical assessment and understanding of attentional risks associated with CP. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A quantitative feedback theory design for attenuation of acoustic noise in earphones and headphones is described. Identification including uncertainty is measured for several ears and device location in the ear neighbourhood. Theoretical limitations are discussed. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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Used therapy analogue studies with Ss who feared snakes or rats to evaluate types of behavior therapy. In a small pilot study Es were able to desensitize 4 Ss to fears of snakes or laboratory rats. However, the 2 control Ss also overcame their fears of snakes. They had been instructed to hold the snake when it was presented to them and to act unafraid. They were also told that they would overcome their fears in this manner. It is suggested that any "technique" that helps a person confront the fear of snakes may "cure" him, that studying the treatment of snake fears may be irrelevant to the understanding of treating clinical neuroses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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