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21.
The global oil market is experiencing a structural shift. Faced with a rapid price decline, large oil-producing countries had decided to protect their market share, with the hopes of permanently removing expensive supply from the market. Meanwhile, the ability of the US shale oil producers to respond quickly to positive price signals puts downward pressure on prices. On the demand side, advances in renewable technology and the continued effort to curb consumption of fossil fuel conspire to inhibit long-run growth.1 These factors suggest that the current down-cycle may continue for an extended period of time or even invoke another down-cycle. 相似文献
22.
K. Brad Wray 《Scientometrics》2009,81(3):757-764
I examine whether the professionalization of science, a process that unfolded between 1600 and 1899, afforded better opportunities
for young scientists to make significant discoveries. My analysis suggests that the professionalization of the sciences did
make it a little easier for scientists to make significant contributions at a younger age. But, I also argue that it is easy
to exaggerate the effects of professionalization. Older and middle age scientists continued to play an important role in making
significant discoveries throughout the history of modern science. 相似文献
23.
When a psychologist is diagnosed with a serious medical condition and faces the prospect of an arduous treatment regimen and perhaps a bleak prognosis, it may be difficult to attend to one's level of professional competence. Like their clients, psychologists are vulnerable to distress and diminished functioning caused by a life-threatening illness. Psychologists have an ethical responsibility to monitor and ensure professional competence, yet the distress and distraction that accompany serious health problems can inhibit and undermine self-assessments of competence in many ways; distressed psychologists may react with denial, shame, fear, and problematic countertransference responses. The limitations associated with evaluating competence in the context of distress are discussed and several recommendations are offered for psychologists who deliver services, support gravely ill colleagues, and serve in credentialing and regulatory capacities. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
24.
Brad Brannon 《电子与电脑》2011,(6):62-64
现在虽然有那么多颗模拟数字转换器(ADC)可供挑选,但是在应用设计时,想了解哪一颗ADC合用,就绝对没有那么简单。技术手册往往让这个问题变得更加复杂,更何况有好多项规格根本是以料想不到的方式在影响性能。 相似文献
25.
Because current federal law prohibits gay, lesbian, and bisexual (GLB) persons from serving openly in the military, the 65,000 GLB men and women estimated to currently serve in the armed forces face unique occupational stressors and a heightened need for supportive services. Psychologists in military settings face numerous obstacles in efforts to provide ethical and efficacious clinical services to GLB service members. The authors highlight common clinical problems and referral issues for GLB persons in military settings, as well as primary ethical and administrative problems for the psychologists who treat them. The authors conclude with several recommendations for enhancing appropriate treatment while minimizing harm to GLB clients in the military. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
26.
Bradley T. Vander Zanden Richard Halterman Brad A. Myers Rob Miller Pedro Szekely Dario A. Giuse David Kosbie Rich McDaniel 《Software》2005,35(13):1275-1298
One‐way constraints have been incorporated in many graphical user interface toolkits because they are simple to learn, easy to write, and can express many types of useful graphical relationships. This paper is an evaluative paper that examines users' experience with one‐way constraints in two user interface development toolkits, Garnet and Amulet, over a 15‐year time span. The lessons gained from this examination can help guide the design of future constraint systems. The most important lessons are that (1) constraints should be allowed to contain arbitrary code that is written in the underlying toolkit language and does not require any annotations, such as parameter declarations, (2) constraints are difficult to debug and better debugging tools are needed, and (3) programmers will readily use one‐way constraints to specify the graphical layout of an application, but must be carefully and time‐consumingly trained to use them for other purposes. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
27.
In a meta-analysis, graphical displays can be used to check statistical assumptions for numerical procedures and they can be used to discover important patterns in the data. The authors propose the normal quantile plot as a preferred alternative to the funnel plot for such purposes. The normal quantile plot, like the funnel plot, can be used to investigate whether all studies come from a single population and to search for publication bias. However, the normal quantile plot is easier to interpret than the funnel plot, especially when it includes 95% confidence bands. In addition, the normal quantile plot can be used to check the normality assumption for numerical procedures. The funnel plot cannot be used for this latter purpose. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
28.
Many individuals intend to exercise, but fail to link this intention to behavior. The present study examined the impact of an implementation intention intervention (i.e., instructions to form specific if-then plans) on an exercise intention-behavior relationship among working adults who varied in reported occupational stress levels. Results indicated that implementation intentions backfired, such that participants who did not form an implementation intention exercised significantly more than participants who formed an implementation intention. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
29.
Graziano William G.; Habashi Meara M.; Sheese Brad E.; Tobin Renée M. 《Canadian Metallurgical Quarterly》2007,93(4):583
This research program explored links among prosocial motives, empathy, and helping behavior. Preliminary work found significant relations among components of self-reported empathy and personality (N = 223). In Study 1, the authors examined the generality of prosocial behavior across situations and group memberships of victims (N = 622). In Study 2, empathic focus and the victim's outgroup status were experimentally manipulated (N = 87). Study 3 (N = 245) replicated and extended Study 2 by collecting measures of prosocial emotions before helping. In Study 4 (N = 244), empathic focus and cost of helping as predictors of helping behavior were experimentally manipulated. Overall, prosocial motivation is linked to (a) Agreeableness as a dimension of personality, (b) proximal prosocial cognition and motives, and (c) helping behavior across a range of situations and victims. In persons low in prosocial motivation, when costs of helping are high, efforts to induce empathy situationally can undermine prosocial behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.
Brian R. Bennett J. Brad Boos Mario G. Ancona N. A. Papanicolaou Graham A. Cooke H. Kheyrandish 《Journal of Electronic Materials》2007,36(2):99-104
Heterostructures for InAs-channel high-electron-mobility transistors (HEMTs) were investigated. Reactive AlSb buffer and barrier
layers were replaced by more stable Al0.7Ga0.3Sb and In0.2Al0.8Sb alloys. The distance between the gate and the channel was reduced to 7–13 nm to allow good aspect ratios for very short
gate lengths. In addition, n+-InAs caps were successfully deposited on the In0.2Al0.8Sb upper barrier allowing for low sheet resistance with relatively low sheet carrier density in the channel. These advances
are expected to result in InAs-channel HEMTs with enhanced microwave performance and better reliability. 相似文献