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61.
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   
62.
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   
63.
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   
64.
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   
65.
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   
66.
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   
67.
This paper presents a mathematical model for laser-induced rapid electro-kinetic patterning (REP) to elucidate the mechanism for concentrating particles in a microchannel non-destructively and non-invasively. COMSOL®(v4.2a) multiphysics software was used to examine the effect of a variety of parameters on the focusing performance of the REP. A mathematical model of the REP was developed based on the AC electrothermal flow (ACET) equations, the dielectrophoresis (DEP) equation, the energy balance equation, the Navier-Stokes equation, and the concentration-distribution equation. The medium was assumed to be a diluted solute, and different electric potentials and laser illumination were applied to the desired place. Gold (Au) electrodes were used at the top and bottom of a microchannel. For model validation, the simulation results were compared with the experimental data. The results revealed the formation of a toroidal microvortex via the ACET effect, which was generated due to laser illumination and joule-heating in the area of interest. In addition, under some conditions, such as the frequency of AC, the DEP velocity, and the particle size, the ACET force enhances and compresses resulting in the concentration of particles. The conditions of the DEP velocity and the ACET velocity are presented in detail with a comparison of the experimental results.  相似文献   
68.
A novel microfluidic device which consists of two stages for particle focusing and separation using a viscoelastic fluid has been developed. A circular capillary tube was used for three-dimensional particle pre-alignment before the separation process, which was inserted in a polydimethylsiloxane microchannel. Particles with diameters of 5 and 10 μm were focused at the centerline in the capillary tube, and the location of particles was initialized at the first bifurcation. Then, 5 and 10 μm particles were successfully separated in the expansion region based on size-dependent lateral migration, with ∼99% separation efficiency. The proposed device was further applied to separation of MCF-7 cells from leukocytes. Based on the cell size distribution, an approximate size cutoff for separation was determined to be 16 μm. At 200 μl/min, 94% of MCF-7 cells were separated with the purity of ∼97%. According to the trypan blue exclusion assay, high viability (∼90%) could be achieved for the separated MCF-7 cells. The use of a commercially available capillary tube enables the device to be highly versatile in dealing with particles in a wide size range by using capillary tubes with different inner diameters.  相似文献   
69.
The academic library, given its often privileged position on campus, is the information source that can include directional as well as general campus facts among the myriad of print and e-resources for reference. Also, an academic library's audiences can be quite varied and include prospective students or parents seeking more general knowledge of the building and the campus. Many times this need for information drives patrons to the library service desks. Sometimes, especially during the high-demand seasons of new student orientation and beginning of the fall semesters, the desk is so busy that many patrons will leave because they don't have the time to wait. To address this immediate need for information, Texas Tech University Libraries developed an interactive kiosk to provide general information for frequently asked questions in a more efficient, creative, and interactive way. The kiosk provides a fun method of satisfying a patron's information needs without the requirement of a staff member or the need to wait in line for help. The kiosk is available as long as the Library is open and provides a variety of useful answers to general questions, as well as facts about the Library.  相似文献   
70.
Applying the Theory of Planned Behavior (TPB), this study examines parents’ attitudes, social norms, self-efficacy, and intentions regarding parental mediation of children’s smartphone use. A survey conducted with parents of young smartphone users aged 10–17 shows that parents tend to perceive discussion-based active mediation to be more desirable, as compared to rule-making restrictive mediation. Findings also indicate that the extent to which parents believe that they have control over their parental mediation practices plays an important role in forming positive intentions to practice parental mediation, regardless of the mediation domain.  相似文献   
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