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61.
不同的民族由于地理、民俗、宗教及价值观念等方面的差异,在表达同一概念时,词汇被赋予了许多的联想意义。掌握汉英颜色词不同的文化联想意蕴,并且了解产生这些不同联想意义的原因不仅有利于提高英语学习水平,还能促进和加强中西文化之间的交流。  相似文献   
62.
刘红  蒋蓓 《学术探索》2012,(7):156-158
闻一多是现代一位出色的装帧家,装帧作品虽然不多,但精品不少,尤以封面设计作品较为突出。闻一多的书籍封面设计,在视觉要素运用上,文字新颖多变,图形表现兼容并蓄,色彩运用简洁鲜明,为我国现代书籍装帧艺术的发展做出了贡献。  相似文献   
63.
认识储层岩石中含油饱和度及饱和度分布,对驱替机理的深入研究是非常重要的。为了搞清储层岩石在驱替过程中的饱和度分布情况,应用工业CT技术,提出了一种储层含油岩芯被驱替后的饱和度分布的CT密度差测量方法。在岩样的同一断面,分别对干岩样、饱和岩样及在驱替后的岩样进行CT扫描,重建相应的断层图象,测量所建图象的灰度值,计算出相应的密度值,用密度差法计算出饱和度及其分布值。在γ射线工业CT机“CD-300BG”上对某油田岩样进行了实际测量,获得的结果说明,采用CT密度差法测量饱和度分布是有效的。该方法与常规驱替法相比较,具有快速、精度高、无损岩样和能模拟地层状态测量等特点,是油田开发、油藏描述和地层评价的一种新的有效方法。  相似文献   
64.
结合古代诗词和文献语料并参考辞书,对“青天”之“青”的意义提出新的看法:“青天”之“青”不表示蓝颜色,而是描述天空呈现出的状态。反映了古代人对天的视觉和心理意象,包括:高远辽阔、神秘静穆的神性特质,也包括清明透彻的世俗观念。  相似文献   
65.
提高能源消耗产出效率是新常态下经济发展的必然趋势,随机扰动和外部环境是研究能源消耗产出效率不可回避的问题,而传统的DEA模型无法剔除非期望产出对效率值的影响。本文通过构建四阶段Bootstrap-DEA-Malmquist模型,采用1990~2014年的省际面板数据作为样本数据,通过松弛指标调整能源投入,剔除外部环境和随机因素对能源效率和能源全要素生产率的扰动,并借助Bootstrap随机抽样法进一步减小由于样本差异造成的影响,从静态和动态两个维度测算了中国能源消耗产出效率和全要素生产率。研究发现,外部环境和随机扰动对能源效率的估算具有显著影响,剔除外部环境影响因素后得到的能源效率值、技术效率变化以及全要素生产率变动均有不同程度的下降,而调整初始投入后的技术进步值有所上升。此外,考虑环境因素时,能源效率值下降,但是进一步运用Bootstrap随机抽样法消除随机因素的影响后,能源效率值有所上升。本文的主要贡献在于将环境因素和随机因素从能源效率与能源全要素生产率的测算中剥离,获得更为准确的能源效率值和能源全要素生产率值。  相似文献   
66.
Framed within contextual systems model, this study examines how home and school operate together to shape behavioral and academic outcomes for 544 low-income African American (56%) and Latino/a (44%) elementary school-aged children (mean age?=?7.88 years, SD?=?1.46, 50% male). Using data from Welfare, Children, & Families Study: A Three City Study and multiple group path analysis, we found that for children in kindergarten through third grade, the adequacy of the home resources was positively related to applied problem scores (e.g. math literacy) and negatively associated with externalizing behavior. For fourth- to sixth-graders, the adequacy of classroom resources was negatively associated with applied problem scores. For both age groups positive teacher–child relational quality was also a positive predictor of externalizing behavior. Results revealed that barriers to parental involvement in school were a negative predictor of applied problem scores for low-income children in early and later elementary school. Implications for policy and practice aimed at strengthening opportunities for children and families from marginalized communities are discussed.  相似文献   
67.
We develop testing procedures which detect if the observed time series is a martingale difference sequence. Furthermore, tests are developed that detect change–points in the conditional expectation of the series given its past. The test statistics are formulated following the approach of Fourier–type conditional expectations first proposed by Bierens (1982 Bierens, H. J. (1982). Consistent model speci?cation tests. J. Econometr. 20:105134.[Crossref], [Web of Science ®] [Google Scholar]) and have the advantage of computational simplicity. The limit behavior of the test statistics is investigated under the null hypothesis as well as under alternatives. Since the asymptotic null distribution contains unknown parameters, a bootstrap procedure is proposed in order to actually perform the test. The performance of the bootstrap version of the test is compared in finite samples with other methods for the same problem. A real–data application is also included.  相似文献   
68.
The access divide was once the basic form of the digital divide. The development of Internet infrastructure has narrowed the access divide and increased application coverage, but it has also touched off a connectivity dividend difference. Taking the online market as an example, we examine the sources of the dividend difference and the factors influencing it with in a connectivity framework. We found that the narrowing of the access divide has resulted in enhanced connectivity and platform development, giving people the chance to benefit from transforming the various assets in which they have previously invested into differentiated compound connectivity capital. In the course, the scale and rate of the conversion are affected by two multiplier effects and especially by online platforms. The process is ultimately expressed in the dividend difference.  相似文献   
69.
Binary data are commonly used as responses to assess the effects of independent variables in longitudinal factorial studies. Such effects can be assessed in terms of the rate difference (RD), the odds ratio (OR), or the rate ratio (RR). Traditionally, the logistic regression seems always a recommended method with statistical comparisons made in terms of the OR. Statistical inference in terms of the RD and RR can then be derived using the delta method. However, this approach is hard to realize when repeated measures occur. To obtain statistical inference in longitudinal factorial studies, the current article shows that the mixed-effects model for repeated measures, the logistic regression for repeated measures, the log-transformed regression for repeated measures, and the rank-based methods are all valid methods that lead to inference in terms of the RD, OR, and RR, respectively. Asymptotic linear relationships between the estimators of the regression coefficients of these models are derived when the weight (working covariance) matrix is an identity matrix. Conditions for the Wald-type tests to be asymptotically equivalent in these models are provided and powers were compared using simulation studies. A phase III clinical trial is used to illustrate the investigated methods with corresponding SAS® code supplied.  相似文献   
70.
In this study, we examined possible gender differences in reasons for faculty attrition during the last 20 years at a small women's liberal arts college. The attrition rate was calculated from archival data collected through old college directories. As in earlier studies, the attrition rate was higher for women (31%) than for men (18.5%). Reasons for leaving the college were assessed in an online survey completed by 45 out of 66 tenure-track or tenured professors who left (excluding retirees). Work–family conflict was the most frequently cited reason for leaving, with disproportionately more women than men giving this reason. Open-ended responses revealed that work–family conflict typically referred to the difficulty of coordinating two careers. Female faculty who left were also significantly more dissatisfied than males with the support for balancing work and family life at the college. The need for colleges to create spousal policies to help faculty coordinate dual careers was discussed.  相似文献   
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