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In this article we consider the scalar transport governed by the convection-diffusion equation with linear production in two dimensions. The underlying idea in the development of a steady discretization scheme is to incorporate the analytical solution, obtained within a one-dimensional context, into the formulation. The method adopted here features exponential character in the weighted coefficients of the matrix equation, which generates a scheme with high accuracy. The analysis is followed by extending this discretization scheme to solve the convection-diffusion-production equation with a source term. In this article we present an analytical validation study of the method applied to two classes of model equations. Having verified that the method applies equally well for a transport scalar in either case with constant or variable flow velocity, we employ the one-dimensional scheme in the predictor and corrector steps to obtain the two-dimensional solution in an alternating direction-implicit fashion. The result obtained for the test considered in this article follows the trend of analytic data. 相似文献
165.
Tony Book 《Renewable Energy》1999,16(1-4)
The literature on creating consumer awareness and acceptance of solar water heating systems for marketing purposes is sparse. This paper discusses some of the sophisticated marketing techniques available and some results.Selling solar water heating systems in Northern European latitudes requires a degree of persistence and commitment that is probably not required in what are regarded as the “sunny climes” around the Mediterranean, the Middle East, Africa, South East Asia and Australasia. 相似文献
166.
Confirmatory factor analysis with robust weighted least squares estimation of the 103 dichotomously scored items of the Child Behavior Checklist/6-18 (T. M. Achenbach & L. A. Rescorla, 2001) in a sample of 516 girls adopted from China (ages 6.0-15.7 years; M = 8.2, SD = 1.9) indicated that the fit of the 8-factor model was good (root-mean-square error of approximation = .047) and was slightly better than what T. M. Achenbach and L. A. Rescorla (2001) reported for the same model (.06). Support for the 2nd-order factor structure of Internalizing and Externalizing Problems also was provided. Comparisons of the mean scores for the syndromes and Internalizing, Externalizing, and Total Problems revealed mostly small differences between the sample of adopted Chinese girls and T. M. Achenbach and L. A. Rescorla's normative samples. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The Oregon 1994 Death With Dignity Act prescribes an evaluation by a psychologist or psychiatrist when the patient is suspected to be suffering from impaired judgment. Several attempts have been made to propose procedures for assessing end-of-life mental conditions and competence. The psychologist's role may include ethical considerations, protecting patients' rights to autonomy, ensuring competent judgment, preventing unnecessary suffering and inappropriate diagnoses of mental disorders, and supporting family members and the health care team. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Tony Wynohrad 《真空研究与实践》2013,25(5):32-35
Ion pumps continue to be a staple in ultra‐high vacuum (UHV) applications. Since their adoption as a primary UHV pump in the 1960's, it has been known that a variety of particles can emanate from within the ion pump and cause undesirable effects on current measurements and optics components. Historically the solution has been baffling and shielding which results in longer conductance paths to the ion pump. Those solutions can work, but require a larger pump and more vacuum plumbing to compensate for conductance losses. The first step was to fully understand the nature of the particles and their charges. Once those were characterized options for emissions reduction were evaluated. It was determined that an efficient design of shielding near the source of the particle generation site was the most cost effective solution. With a slight modification to the chamber of a small ion pump, internal shielding was developed that reduced the emissions by a factor of up to 1000 times. 相似文献
170.
Halford W. Kim; Wilson Keithia; Watson Bronwyn; Verner Tony; Larson Jeffry; Busby Dean; Holman Thomas 《Canadian Metallurgical Quarterly》2010,24(2):188
To evaluate the effective components of couple relationship education, 59 newlywed couples were randomly assigned to one of two couple relationship programs (CRE): (1) RELATE, which involved receiving feedback on their relationship based on the on-line RELATE assessment; or (2) RELATE + Couple CARE, which was RELATE plus completing the 6 unit Couple CARE relationship skill training program. Relative to RELATE, RELATE + Couple CARE produced more improvement in couple communication, and high relationship satisfaction across the next 12 months in women. Men sustained high and similar relationship satisfaction in either condition. Skill training CRE has additional benefits for couples beyond assessment and feedback. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献