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21.
The non-linear thermo-metallurgical problem, relevant for the cooling of a molten metal including the macro-segregation that occurs during the cooling process, is studied here. Due to the strong non-linearities involved in phase transformations, it is necessary to use a fine resolution in space-time in a finite element approximation in order to meet accuracy requirements. We derive space-time FE-methods based on the discontinuous and continuous Galerkin method in time for the energy equation. This formulation integrates the stored energy exactly for a given heat flux. When macro-segregation is incorporated into the model, the problem can be formulated in such a way that the phase-transition drives a flow of species. In addition, diffusion is possible throughout the domain. The model can be further rewritten using a potential approach. By this approach for modelling macro-segregation, we are able to obtain discretizations that guarantee that the balance equations are satisfied, and it is possible to solve the phase-transition problem either as a field problem or as a local problem (defined by a local evolution rule).  相似文献   
22.
Changes in maladaptive cognitions may constitute therapeutic processes of multidisciplinary pain programs. A cross-lagged panel design was used to determine whether (a) early-treatment cognitive change predicted late-treatment outcome index change, but not vice versa; and (b) these effects remained significant with depression change controlled. Ninety chronic pain patients, in a 4-week multidisciplinary program, completed measures of catastrophizing, pain helplessness, depression, pain, interference, and activity level at pre-, mid-, and posttreatment. With depression changes controlled, early-treatment catastrophizing and pain helplessness changes predicted late-treatment outcome index changes, but not vice versa; early-treatment depression changes predicted late-treatment activity changes, but not vice versa. Findings advance understanding of pain treatment process and suggest that negative cognition changes may indeed affect improvements in treatment outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
23.
With worldwide energy consumption rising, there is a need to reduce energy use of the housing stock. While this general idea is well-known, there is an overwhelming amount of product data and manufacturers claims through which the homebuilder or designer must sort to make informed selections of energy-efficient upgrades. The main objective of this research was to identify cost effective–energy efficient upgrades from a group of 16 commonly available choices, and rank them according to the most beneficial for the least cost. This study was conducted in Phoenix, Arizona, and included a sample of 30 production-style homes typical of the Phoenix metropolitan area. Energy-simulation software was used to perform energy evaluations and derive the benefits of each upgrade. The cost of each upgrade was obtained from a database of national average costs and from a local context. Differences in the selection of beneficial upgrades vary dramatically with the source of the cost information. This research provides a generic methodology that can be used by builders and designers to select appropriate energy-efficient upgrades for a given geographic area that will provide high operating benefits relative to the amount of capital investment.  相似文献   
24.
There is an absence of comprehensive, systematically gathered data concerning psychologists' beliefs about and compliance with ethical principles. Furthermore, we know little about which resources are valued as effective in guiding appropriate behavior. Survey data were collected from 456 APA Division 29 members regarding the degree to which they engaged in each of 83 behaviors and the degree to which they considered each behavior to be ethical. These data were categorized and examined in terms of five principles derived from the Hippocratic oath (avoiding harm, competence, avoiding exploitation, respect, and confidentiality) as well as two additional principles (informed consent; social equity and justice). Twelve of the behaviors were very difficult for participants to evaluate on the basis of ethics. Seven of the 83 behaviors were practiced by over 90% of the participants; 16 by fewer than 10%. Colleagues, the APA Ethical Principles, and internship training were rated as the most helpful resources in guiding behavior; state and federal laws, published research, and local ethics committees were rated least helpful. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
25.
Kenneth Train 《Energy》1985,10(12):1243-1253
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26.
A framework for incorporating uncertainty in risk management is developed and applied to two aspects of decision making: meeting standards or safety goals, and cost-benefit criteria. The framework is applied to several case studies including toxic chemicals in water, failure of civil engineering structures and nuclear power plants. The framework proposes that decisions be based on a level of confidence, in addition to comparing best estimate or point values with standards and goals.  相似文献   
27.
This article reports the results of a study conducted to examine the ability of the Situational Outlook Questionnaire (SOQTM) to effectively discern climates that either encourage or discourage creativity and the ability to initiate change in a team setting. The purpose of the study is to examine the concurrent criterion–related validity of the SOQ. The article explores the characteristics in an organisational climate that promote teamwork and some of the tripwires one needs to be aware of in the formation and management of teams. Nine dimensions of the climate for creativity and change as measured by the Situational Outlook Questionnaire are put forward and defined in relation to teams. The methodology and results of the study are reported. The results show that when subjects (N7equals;154) complete the SOQ based on their recollection of a best– and worst–case team experience, the measure is able to consistently and significantly discriminate between the two types of experiences. Conclusions, implications, and areas for future research to further examine the validity of the SOQ are explored.  相似文献   
28.
Examined the relation between gender and reactions to different styles of advertising tobacco and alcohol products among 41 females and 34 males (aged 12–16 yrs) and their parents (39 mothers and 36 fathers). Self-monitoring was also examined as a possible correlate. Ss rated magazine advertisements oriented toward the product's image or qualities. Girls liked image-oriented advertisements more and perceived them to be more persuasive than quality-oriented advertising. This gender difference was not observed among adults. All Ss liked image-oriented more than quality-oriented advertising. Moreover, image-oriented advertisements were seen as more persuasive than quality-oriented advertisements by girls' parents who were high in self-monitoring. Results suggest that girls in early adolescence may be particularly attentive to image-oriented commercials that portray smoking and drinking as desirable behaviors. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
29.
The immediate goal of any clinical trial is to determine to which of a specified set of treatments future patients are to be assigned, particularly when analyzing data from clinical trials. When the outcome distributions of Experimental (E) and Control (C) treatments overlap, differences between treatment group means are not conclusive and may not be very informative, so a display of the overlapped frequency distributions and a summary measure of the probability of a random patient in E doing better than a random patient in C are needed. When outcome distributions overlap, the question of statistical model becomes crucial even when there are very significant differences between group means and very large effect sizes. Determining what patient variables interact with treatments is the route to optimal assignment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
30.
Performed a correlational analysis of attendance records and grades in a 1st-yr psychology class. 103 undergraduates were informed that the attendance records would not affect their grades in the course. A positive correlation was found between attendance and final grades in the course. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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