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101.
102.
本文将计算机的应用延伸到《青年心理研究》课题中,利用统计分析方法,以《青年心理研究》课题为基础,研制开发出了一个功能齐全,性能优良,统计分析系统全面的心理学研究软件,为心理学的研究提供一个可行又可靠的工具,也为其它社会科学提供一种全新的研究手段。 相似文献
103.
Longitudinal data from a national sample of Germans (N = 20,434) were used to evaluate stability and change in the Big Five personality traits. Participants completed a brief measure of personality twice, 4 years apart. Structural equation modeling techniques were used to establish measurement invariance over time and across age groups. Substantive questions about differential (or rank-order) and mean-level stability and change were then evaluated. Results showed that differential stability was relatively strong among all age groups but that it increased among young adults, peaked in later life, and then declined among the oldest old. Patterns of mean-level change showed that Extraversion and Openness declined over the life span, whereas Agreeableness increased. Mean levels of Conscientiousness increased among young adults and then decreased among older adults. Trajectories for Neuroticism were relatively flat, with slight increases during middle age and a slight decline in late life. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
104.
105.
文章系统分析了葡萄品种学研究的发展历史及现状,对研究内容的系统化、研究手段的现代化、数量化,研究方法的规范化作了详细论述。 相似文献
106.
Armour Cherie; McBride Orla; Shevlin Mark; Adamson Gary 《Canadian Metallurgical Quarterly》2011,3(2):139
The Simms et al. (2002) four-factor structure of posttraumatic stress disorder (PTSD) has been supported in many factor analytic studies, and the specificity of the dysphoria factor has been questioned because of its strong associations with measures of depression and anxiety. This study addressed this issue by conducting a confirmatory factor analysis while controlling for the symptoms of major depression (MD) and generalized anxiety disorder (GAD). Data from individuals who satisfied Criterion A of the diagnostic criteria for a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM–IV) diagnosis of PTSD (n = 12,467) in the 2004–2005 National Epidemiologic Study on Alcohol and Related Conditions (NESARC) were used in the analysis. The results showed that after controlling for MD and GAD, the factor loadings for dysphoria items were significantly attenuated, although they remained relatively high and statistically significant. The present findings contribute to the debate regarding how PTSD should be conceptualized and assessed in future issues of the DSM. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
107.
在旋风分离单管末端常采用直锥结构来提高分离效率,然而实际使用过程中常常发现在直锥的上部存在“下灰环”,对单管局部造成严重磨损,对整个装置的安全运行构成极大威胁。下灰环的形成主要是由于单管末端收缩曲线不光滑造成的。为了验证这个假设,选择了航空风洞收缩段常用的双三次方曲线作为单管末端收缩曲线,制成所谓双三次方锥并且做了流场显示实验。实验结果初步证实了这个假设 相似文献
108.
Reference materials (RM) play an increasingly important role for laboratories. The aim of this work is to compare different
conditions of storage and assess the stability of agrifood external reference materials (ERM). These materials could be used
as tools by laboratories notably for their quality control procedure. However, as the other RM, their stability must be assessed
during stability studies. The determination of the limiting date of stability (LDS), defined as the period during which analytes
called marker of stability are still considered as stable, is used on this purpose. The influences of the environmental factor
were tested by the application of full experimental designs with two tested environmental factors: the temperature (storage
at +4 °C or +20 ± 10 °C) and the composition of the atmosphere (absence or presence of gases in the packaging). Thus, the
setting under vacuum increases clearly the stability for the studied analyte. Almost all ERM stored in the best conditions
have a determined LDS higher than those stored in current condition of storage. Indeed, the bread wheat ERM LDS is higher
than the current storage of 24 months 相似文献
109.
含油气盆地低渗透储层构造裂缝定量预测方法和实例 总被引:4,自引:4,他引:0
含油气盆地储层裂缝特征参数的定量表征和空间分布规律定量预测,仍是石油地质领域的前
沿问题之一。低渗透储层的一个显著特点是不同程度上发育构造裂缝系统,是我国非常重要
的油气储层类型,因此,开展低渗透储层构造裂缝分布规律的合理预测评价,无疑会对油气
勘探与开发起到积极的指导作用。构造裂缝预测研究的基本方法有岩石破裂法、主曲率法、
能量法、统计学方法。以鄂尔多斯盆地沿河湾探区为例,以统计法为基础,结合运用岩石破
裂法和能量法,定量预测和评价了该探区上三叠统延长组主要目的层长61低渗透储层裂缝
的分布和发育状况,为该探区油气的进一步勘探与开发提供了重要的地质依据。 相似文献
110.
气井泡沫排水中起泡剂的研究与应用 总被引:2,自引:0,他引:2
气井泡沫排水中使用的起泡剂直接影响气井的排水效率,是决定泡沫排水成功与否的关键。文章介绍了国虎近年来起泡剂的研究与应用情况,指出了现有起泡剂存在的问题和今后的研究方向。 相似文献