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51.
The latent growth model (LGM) in structural equation modeling (SEM) may be extended to allow for the modeling of associations among multiple latent growth trajectories, resulting in a multiple domain latent growth model (MDLGM). While the MDLGM is conceived as a more powerful multivariate analysis technique, the examination of its methodological performance is very limited. Hence, the present study compared the power of the MDLGM with that of a set of univariate LGMs for detecting group differences in growth rates over time using a Monte Carlo study with a two-group and two-domain design. The results indicated that there were different scenarios where the power rates for the MDLGM were greater than that of the set of LGMs (and vice versa) due to a joint function of the two domains’ intercorrelation size and the group difference effect size. 相似文献
52.
亢玲莉 《山西师大学报(社会科学版)》2005,32(5):34-36
随着经济全球化的发展,企业跨国投资的步伐愈来愈快。在跨国投资过程中,企业也会面临各种困难与风险。发达国家在企业跨国投资过程中,运用税收、信贷、保险等金融手段对境外投资给予促进和必要的制约,从而分散企业的经营风险。我国企业在跨国投资过程中,也应该借鉴国际经验,建立和完善企业境外投资的税收制度,加大企业信贷优惠政策扶持力度,完善企业境外投资保险制度、企业境外投资准备金制度、中小企业境外投资的融资政策等,以分散企业的经营风险。 相似文献
53.
54.
Yiu-yin Lee 《浙江大学学报(A卷英文版)》2017,18(1):75-82
This paper addresses the effect of leakage on the natural frequencies of a large amplitude vibrating panel backed by a cavity, which has not been considered in many other related studies. The structural-acoustic governing equations are employed to study this nonlinear problem. An elliptical integral method, which was recently developed for the nonlinear panel cavity problem, is introduced here to solve for the structural-acoustics responses. The present results agree reasonably well with those obtained from the classical harmonic balance method. Modal convergences of the nonlinear solutions are performed to verify the proposed method. The effects of vibration amplitude and leakage size are studied and discussed. It is found that (1) the edge leakages in a panel cavity system significantly affect the natural frequency properties, and (2) the edge leakages induce a low frequency acoustic resonance. 相似文献
55.
康克军 《阿坝师范高等专科学校学报》2002,(1):124-126
人们对中小学校图书馆室等基础功能设施建设重视不够。文章从图书馆室的装备、管理和效益三个方面,结合民族地区的特点和教育现状,提出了民族地区中学小校图书馆室建设和管理模式,供当地教育行政部门和学校参考。 相似文献
56.
Tenko Raykov Thanos Patelis George A. Marcoulides Chun-Lung Lee 《Structural equation modeling》2016,23(1):111-115
This article outlines an interval estimation procedure that can be used in a 3-level setting to evaluate the proportion of outcome variance attributable to the second level of clustering. The method is useful for examining the necessity of including a possibly omitted intermediate level of nesting in analyses of data from a multilevel study, and represents an informative addendum to current statistical tests of second-level variance. The approach is developed within the framework of latent variable modeling and can be used as an aid in the process of choosing between 2-level and 3-level models in a hierarchical design. The discussed procedure is illustrated with an empirical example. 相似文献
57.
Many have called for re-examination of the “colorblind” philosophy to which some early educators have, tacitly or explicitly, adhered (e.g. Boutte et al. 2011; Derman-Sparks and Edwards 2010; Husband 2012). It has been argued that, while colorblind approaches may appear to be politically neutral, they actually exacerbate racial oppression. In this article, we advocate for a direct and active approach to raising conversations about race with younger preschool children. Based on the developmental nature of young children’s concepts of self and of other, our focus is on initiating discussions about concrete and observable physical aspects of human diversity associated with race. Young children notice and are curious about differences in skin color, hair texture, and facial features. Because these differences are salient, are accessible, and are of interest to young children they can serve as an effective starting point. We suggest shared reading of high quality illustrated children’s books, incorporating the principles of dialogic reading, as a potent springboard for discussions about race with very young children. Our purpose is to equip children, very early in their schooling, with a color-filled appreciation for and comfort with physical diversity of appearance. On that foundation, children may better proceed on the course of developing anti-racist attitudes. 相似文献
58.
Chang Xin Zhang Chengyu Gao Lan Liu Xiao You Shengping Qi Wei Wang Kang Guo Xin Su Rongxin Lu Han He Zhimin 《天津大学学报(英文版)》2019,25(5):488-496
2,5-Furandicarboxylic acid(FDCA) is a potential biorenewable chemical for applications including plastics, polyamides, drugs, etc. The selective biosynthesis of FDCA from 5-hydroxymethylfurfural(HMF) by a specific enzyme poses a great challenge. In this study, we reported an efficient strategy to produce FDCA from HMF by the tandem biocatalysis of laccase(Cot A-TJ102@UIO-66-NH_2) and Novozym 435. For the first step, a nanoparticle metal–organic framework was synthesized as a carrier to immobilize Cot A-TJ102@UIO-66-NH_2, which was assigned for the production of 5-formyl-2-furancarboxylic acid(FFCA) and featured an enzyme loading of 255.54 mg/g, specific activity of 135.90 U/mg, and solid loading ratio of 99.65%. Under optimal conditions, an ideal FFCA yield of 98.5% was achieved, and the Cot A-TJ102@UIO-66-NH_2 presented a high recycling capacity after 10 cycles. For the second step, Novozym 435 was applied for the further conversion of FFCA into FDCA, presenting a high FDCA yield of 95.5% under the optimized conditions. Novozym 435 also exhibited a high recyclability after eight cycles. As a result, the tandem biocatalysis strategy provided a 94.2% FDCA yield from HMF, indicating its excellence as a method for FDCA production. 相似文献
59.
A previous meta-analysis indicated that eight instructional factors--Questioning, Sequencing and Segmentation, Skill Modeling, Organization and Explicit Practice, Small-Group Setting, Indirect Teacher Activities (e.g., homework), Technology, and Scaffolding-captured the majority of successful intervention programs for adolescents with learning disabilities (LD). Most important was the Organization/Explicit factor, which contributed significant variance (16%) to effect size. This factor included two important instructional components: advance organization and explicit practice. In this article, we convert these findings into practical guidelines to direct instructional practice. 相似文献
60.
Paul Kim Teresita Hagashi Laura Carillo Irina Gonzales Tamas Makany Bommi Lee Alberto Gàrate 《Educational technology research and development : ETR & D》2011,59(4):465-486
Mobile devices are highly portable, easily distributable, substantially affordable, and have the potential to be pedagogically
complementary resources in education. This study, incorporating mixed method analyses, discusses the implications of a mobile
learning technology-based learning model in two public primary schools near the Mexico-USA border in the state of Baja California,
Mexico. One school was located in an urban slum and the other in a rural village community. Empirical and ethnographic data
were collected through a series of achievement tests, observations, surveys, and interviews involving 160 s grade school children
recruited by convenience sampling. The general technology infrastructure, distinctive features of mobile learning to supplement
literacy development, profound contextual phenomena arising from the two uniquely underserved communities, and social factors
possibly influencing the educational experiences are discussed. The findings suggest that students in the rural village, seriously
lacking educational resources and technology exposure, may have benefited substantially more from mobile technologies than
urban school students possibly due to their relatively higher socio-economic status and higher parental involvement and interest
in education. In contrast, there was no evidence of interaction with parental education levels, the experience of teachers
or school principals, or the teacher’s perception or preparation of the technology. Overall, the mobile learning technology
adoption was rapid, seamless, and actively driven by the students rather than the teacher. The challenges of the phenomenal
migratory nature of most families in this unique geographical region are also discussed to benefit future studies. 相似文献