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Reduction of optical proximity effects (OPE), at deep uv wavelength of 248nm, caused by the variation of stepper lens operating conditions is investigated. It is shown that many of these effects, which increase as the Rayleigh limit is approached, can be minimised, and in many cases eliminated, by suitable choice of lens numerical aperture (NA) and partial coherence (sigma, σ).
Application of these results should enable the user of advanced wafer steppers to carry out high resolution lithography with a minimum of time consuming optical proximity correction (OPC). 相似文献
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A structural model of science achievement and attitude: An extension to high school. 总被引:1,自引:0,他引:1
A previous structural model of Walberg's theory of educational productivity (A. J. Reynolds and H. J. Walberg, 1991) was tested with a national probability sample of 2,535 10th graders for science achievement and attitude. Using data from the Longitudinal Study of American Youth, a 3-wave design incorporated information from students, teachers, and parents. Results indicate that a revised mediated-effects model fit the data best and accounted for substantial variance in Grade 11 science achievement (56%) and attitude (44%). The variables prior achievement, home environment, exposure to mass media through reading, and instructional time had the greatest total effects on science achievement. Prior attitude, home environment, motivation, and prior achievement made the greatest total contributions to science attitude. Although there were different weightings of the factors between the present study and Reynolds and Walberg (1991), both studies support a mediated-effects model of educational productivity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Language-level support for object persistence frees programmers from having to confront a broad class of database issues from within their applications. By virtue of its metaobject protocol, CLOS is a language whose semantics can be tailored by individual programmers. We used the metaobject protocol to extend CLOS with support for object persistence. Our goal was to obtain a version of CLOS with persistence to which we could easily port a commercial geometric CAD modeling system. We describe the design and implementation of our persistence extension and highlight the strengths and weaknesses exhibited by the CLOS metaobject protocol during our experiment. For many aspects of the implementation we found that the metaobject protocol was ideal. In other cases we had to choose among paying a large performance penalty, extending the protocol, and bypassing the protocol by modifying the language implementation directly. 相似文献
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Avants S. Kelly; Margolin Arthur; Kosten Thomas R.; Rounsaville Bruce J.; Schottenfeld Richard S. 《Canadian Metallurgical Quarterly》1998,66(6):924
In response to a need to match drug users to the most appropriate and cost-effective level of care, it was hypothesized that socially anxious methadone-maintained patients would attain greater benefit from coping skills training provided in the context of a low-intensity enhanced standard methadone maintenance intervention (E-STD) than in the context of a high-intensity, socially demanding day treatment program (DTP). Social anxiety was assessed in 307 methadone-maintained patients using the Social Anxiety and Distress Scale prior to randomization to either E-STD or DTP. The hypothesis was supported: Socially anxious patients were drug free longer during treatment, were more likely to be abstinent at treatment completion, and had greater reductions in HIV risk behaviors if assigned to the lower intensity intervention, which was provided at ? the cost of the DTP. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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For standard, single-level mathematical programs, any optimal solution remains optimal when an inactive (i.e., irrelevant) constraint is added to the problem, a property termed independence of irrelevant constraints (IIC). In general, bilevel mathematical programs do not possess the IIC property. This paper presents necessary and sufficient conditions for the IIC property to hold for a bilevel program. A straightforward test is described that concludes whether or not a bilevel program is IIC. 相似文献
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Bachant Janet L.; Lynch Arthur A.; Richards Arnold D. 《Canadian Metallurgical Quarterly》1996,13(1):153
The authors respond to the "relational" issue of Psychoanalytic Psychology (PP; Vol. 12, No. 1) and support Karol Marshall's remonstration about the need to clarify what exactly the category relational refers to. It is noteworthy that in this issue of PP the relational thinkers do not engage the specific topics of our essay. The author's article attempted to review the most comprehensive relational thinkers of that time across theoretical variables. Relationalists have begun to spell out the technical consequences of their perspective in recent discussions of neutrality, authority, and self-disclosure, among other issues. This is a useful trend in the relational literature, and we hope it continues. We are concerned, however, that the relational thinkers writing in this issue tend to dismiss the contributions to PP 12(1) because the perspectives presented there did not satisfy the relationalist vision of how scientific exchange should be undertaken. Although we feel that it is important for emerging points of view to be able to elaborate assumptions, constructs, and principles within their own framework and in their own way, constructive dialogue, much less a comparative analysis of the contributions and limitations of different points of view, requires that we have some common ground. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献