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31.
依据热平衡方法测流量原理研制的热平衡流量计没有任何可动部件,可靠性大大加强,可以代替常用的浮子流量计和涡轮流量计。该仪器的应用为油水井及注聚合物井的流量测试提供了更为有效的手段和方法。  相似文献   
32.
The current study prospectively followed girls with attention-deficit/hyperactivity disorder (ADHD), along with a matched comparison sample, 5 years after childhood neuropsychological assessments. Follow-up neuropsychological measures emphasized attentional skills, executive functions, and language abilities. Paralleling childhood findings, the childhood-diagnosed ADHD group displayed moderate to large deficits in executive/attentional performance as well as in rapid naming relative to the comparison group at follow up (Mage 14.2 years). ADHD-inattentive versus ADHD-combined contrasts were nonsignificant and of negligible effect size, even when a refined, sluggish cognitive tempo subgroup of the inattentive type was examined. Although ADHD versus comparison group differences largely withstood statistical control of baseline demographics and comorbidities, control of childhood IQ reduced executive function differences to nonsignificance. Yet when the subset of girls meeting diagnostic criteria for ADHD in adolescence was compared with the remainder of the participants, neuropsychological deficits emerged even with full statistical control. Overall, childhood ADHD in girls portends neuropsychological and executive deficits that persist for at least 5 years. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
33.
新型低伤害压裂液的研究与应用   总被引:1,自引:1,他引:0  
针对安棚油田特低孔特低渗、储层温度高、微裂缝发育等地质特征 ,通过室内实验 ,研制出具有耐高温、低伤害、延迟交联等特点的新型压裂液体系 ,并进行了 2 0多井次的现场试验。结果表明 ,该压裂液具有很好的适应性 ,完全可满足安棚油田特低孔特低渗储层压裂改造的要求  相似文献   
34.
闫荣春  许罕多 《山西建筑》2008,34(11):241-242
对"比较法"原理和应用情况进行了分析,说明其在房地产开发中能够科学地预测房地产的价格和收益,从而提高财务分析的科学性和权威性,为项目决策提供科学依据,以促进"比较法"在房地产开发中的应用。  相似文献   
35.
Struts是基于模型视图控制体系(MVC)的Web应用框架。详细介绍了基于MVC体系的Struts工作原理,探讨应用Struts框架构建企业级应用系统的步骤及方法。给出了基于Struts的科研资源计划系(SRRPS)的设计实现,结果表明Struts框架能极大地提高系统的可扩展性、可重用性及可维护性。  相似文献   
36.
Psychologists' appropriation of language and ideas from Thomas Kuhn's (1962, 1970b) The Structure of Scientific Revolutions reveals deep and contradictory concerns about truth, science, and the progress of the field. The author argues that psychologists, uncomfortably straddling natural and social science traditions, reference Structure for 2 reasons largely overlooked: first, because it presents an intermediate, naturalistic position in the war between relativist and rationalist views of scientific truth, and second, because it presents a psychologized model of scientific change. The author suggests that the history of this mutual influence--psychologists being influenced by Kuhn and vice versa--may usefuly inform current practices of psychological science. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
37.
Education-driven research in CAD   总被引:1,自引:0,他引:1  
Jarek   《Computer aided design》2004,36(14):1461-1469
We argue for a new research category, named education-driven research (EDR), which fills the gap between traditional field-specific research that is not concerned with educational objectives and research in education that focuses on fundamental teaching and learning principles and possibly on their customization to broad areas (such as mathematics or physics), but not to specific disciplines (such as CAD). The objective of EDR is to simplify the formulation of the underlying theoretical foundations and of specific tools and solutions in a specialized domain, so as to make them easy to understand and internalize. As such, EDR is a difficult and genuine research activity, which requires a deep understanding of the specific field and can rarely be carried out by generalists with primary expertise in broad education principles. We illustrate the concept of EDR with three examples in CAD: (1) the Split and Tweak subdivisions of a polygon and its use for generating curves, surfaces, and animations; (2) the construction of a topological partition of a plane induced by an arbitrary arrangement of edges; and (3) a romantic definition of the minimal and Hausdorff distances. These examples demonstrate the value of using analogies, of introducing evocative terminology, and of synthesizing the simplest fundamental building blocks. The intuitive understanding provided by EDR enables the students (and even the instructor) to better appreciate the limitations of a particular solution and to explore alternatives. In particular, in these examples, EDR has allowed the author to: (1) reduce the cost of evaluating a cubic B-spline curve; (2) develop a new subdivision curve that is better approximated by its control polygon than either a cubic B-spline or an interpolating 4-point subdivision curve; (3) discover how a circuit inclusion tree may be used for identifying the faces in an arrangement; and (4) rectify a common misconception about the computation of the Hausdorff error between triangle meshes. We invite the scientific community to encourage the development of EDR by publishing its results as genuine research contributions in peer-reviewed professional journals.  相似文献   
38.
Advances in research on disability and rehabilitation are essential to creating equal opportunity, economic self-sufficiency, and full participation for persons with disabilities. Historically, such initiatives have focused on separate and specific areas, including neuroscience, molecular biology and genetics, gerontology, engineering and physical sciences, and social and behavioral sciences. Research on persons with disabilities should examine the broader context and trends of society that affect the total environment of persons with disabilities. This article examines the various disability paradigms across time, assessing the relative contribution of the socioecological perspective in guiding research designed to improve the lives of persons with disabilities. The authors recommend new research directions that include a focus on life span issues, biomedicine, biotechnology, the efficacy and effectiveness of current interventions, an emphasis on consumer-driven investigations within a socioecological perspective of disability, and the implications for research and practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
39.
Why was there a preponderance of women engaged in laboratory-based studies of animal behavior in Britain in the early years of the 20th century? As a new experimental subject with recently neglected potential, animal psychology then represented an opportunity for women to make further inroads into academic science. Because the study of psychology before World War I offered negligible professional opportunities for the application of the subject, the intake of students was restricted. Perhaps this encouraged academic access to it by aspiring female scientists who felt that career prospects, uncertain and socially unexpected of them in any case, were worth chancing for greater long-term rewards. The academic circumstances and contributions of 3 British female pioneers in experimental comparative psychology are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
40.
介绍了丹江口二桥深水墩基础施工平台的设计,重点介绍利用ANSYS通用有限元程序对施工平台的施工过模拟分析,以及对分析结果的总结。  相似文献   
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