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111.
在全面总结韩国技术竞争情报(CTI)服务的兴起及发展历史的基础上,客观分析了其CTI应用的特点及其效果, 并且对韩国企业开展CTI活动的动力因素及其影响进行了深入研究. 相似文献
112.
This article extends the Bonett (2003a) approach to testing the equality of alpha coefficients from two independent samples to the case of m ≥ 2 independent samples. The extended Fisher-Bonett test and its competitor, the Hakstian-Whalen (1976) test, are illustrated with numerical examples of both hypothesis testing and power calculation. Computer simulations are used to compare the performance of the two tests and the Feldt (1969) test (for m = 2) in terms of power and Type I error control. It is shown that the Fisher-Bonett test is just as effective as its competitors in controlling Type I error, is comparable to them in power, and is equally robust against heterogeneity of error variance. 相似文献
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Hyo Jung Kim 《亚洲交流杂志》2018,28(5):541-558
This study investigates how the public’s perceptions of nuclear power, one of the modern technologies at the center of public debate on risk issues, are influenced by gain versus loss framing in the volatile context of nuclear energy applications in South Korea. Drawing upon prospect theory as its conceptual framework, this experiment using 566 adult participants found that loss-framed messages (i.e. emphasizing the negative outcomes of not using nuclear power) were more effective in increasing participants’ message credibility perceptions as compared to gain-framed messages (i.e. emphasizing the positive outcomes of using nuclear power). Additionally, the results found issue involvement to be a significant moderator of the framing effect, by demonstrating that the advantage of loss framing was stronger for participants who were highly involved in nuclear energy issue, as compared to those who were less involved in the issue. The theoretical and practical implications of these findings are discussed. 相似文献
115.
Appropriate model specification is fundamental to unbiased parameter estimates and accurate model interpretations in structural equation modeling. Thus detecting potential model misspecification has drawn the attention of many researchers. This simulation study evaluates the efficacy of the Bayesian approach (the posterior predictive checking, or PPC procedure) under multilevel bifactor model misspecification (i.e., ignoring a specific factor at the within level). The impact of model misspecification on structural coefficients was also examined in terms of bias and power. Results showed that the PPC procedure performed better in detecting multilevel bifactor model misspecification, when the misspecification became more severe and sample size was larger. Structural coefficients were increasingly negatively biased at the within level, as model misspecification became more severe. Model misspecification at the within level affected the between-level structural coefficient estimates more when data dependency was lower and the number of clusters was smaller. Implications for researchers are discussed. 相似文献
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Wee Pin Goh Jonathan Lee Ong Kim Hairon Salleh 《International Journal of Educational Research》2009,48(4):258-273
Self-rating bias is particularly likely in organizational behavior research as individuals tend to inflate their expertise, skills and character. This study aims to examine how two culturally diverse groups of teachers and their reporting officers respond to self-ratings of their own teaching skills and leadership skills respectively. It is posited that such response may be culturally based. To ensure validity of comparisons, analyses were done using linear Rasch measures in logits rather than the non-linear raw scores. No significant differences were found between the perceptions of Singaporean teachers and their reporting officers on teaching and leadership skills. The Bahraini data however revealed teachers’ perceptions of own teaching skills were significantly higher than that of their reporting officers. The opposite is true for the Reporting officers’ perceptions of our leadership skills. Bahraini teachers’ perceptions of their own teaching skills were also found to be significantly higher than that of their Singaporean counterparts. The findings support the notion that individuals’ thinking and behavior is influenced by how they process social and cultural information. 相似文献
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119.
In this study, a multiple sample dispenser for precisely metered fixed volumes was successfully designed, fabricated, and fully characterized on a plastic centrifugal lab-on-a-disk (LOD) for parallel biochemical single-end-point assays. The dispenser, namely, a centrifugal multiplexing fixed-volume dispenser (C-MUFID) was designed with microfluidic structures based on the theoretical modeling about a centrifugal circumferential filling flow. The designed LODs were fabricated with a polystyrene substrate through micromachining and they were thermally bonded with a flat substrate. Furthermore, six parallel metering and dispensing assays were conducted at the same fixed-volume (1.27 μl) with a relative variation of ±0.02 μl. Moreover, the samples were metered and dispensed at different sub-volumes. To visualize the metering and dispensing performances, the C-MUFID was integrated with a serpentine micromixer during parallel centrifugal mixing tests. Parallel biochemical single-end-point assays were successfully conducted on the developed LOD using a standard serum with albumin, glucose, and total protein reagents. The developed LOD could be widely applied to various biochemical single-end-point assays which require different volume ratios of the sample and reagent by controlling the design of the C-MUFID. The proposed LOD is feasible for point-of-care diagnostics because of its mass-producible structures, reliable metering/dispensing performance, and parallel biochemical single-end-point assays, which can identify numerous biochemical. 相似文献
120.
Mass transport in porous materials is universal in nature, and its worth attracts great attention in many engineering applications. Plant leaves, which work as natural hydraulic pumps for water uptake, have evolved to have the morphological structure for fast water transport to compensate large water loss by leaf transpiration. In this study, we tried to deduce the advantageous structural features of plant leaves for practical applications. Inspired by the tissue organization of the hydraulic pathways in plant leaves, analogous double-layered porous models were fabricated using agarose hydrogel. Solute transport through the hydrogel models with different thickness ratios of the two layers was experimentally observed. In addition, numerical simulation and theoretical analysis were carried out with varying porosity and thickness ratio to investigate the effect of structural factors on mass transport ability. A simple parametric study was also conducted to examine unveiled relations between structural factors. As a result, the porosity and thickness ratio of the two layers are found to govern the mass transport ability in double-layered porous materials. The hydrogel models with widely dispersed pores at a fixed porosity, i.e., close to a homogeneously porous structure, are mostly turned out to exhibit fast mass transport. The present results would provide a new framework for fundamental design of various porous structures for effective mass transport. 相似文献