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71.
The studies pertaining to expertise development are diverse and broad (Bjork, 1994; Einstein & McDaniel, 2005; Schneider, Healy, & Bourne, 2002), yet empirical research that bridges expertise development into instructional design theories is still in its very formative stages (Ertmer et al., 2008; Fadde, 2009). This article is intended to identify the instructional principles that are effective in accelerating the performance of journeymen, considering the significant impact of the journeyman stage and the need for hastening performance in that stage. With the introduction to the major scholarly works and principles that have led to the elaboration of training methods, strategies, and materials, this review of literature proposes a learning model that has four components: (1) development plan, (2) action, (3) reflection‐on‐action, and (4) remedies.  相似文献   
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This study examined the actual practice and effectiveness of a satellite educational TV program in Ethiopian secondary schools. Participants in the survey were 228 students and 63 teachers from secondary schools. The results of the data analysis indicate that Ethiopian students and teachers scored highly in the evaluation areas. Levels of students’ general satisfaction with the satellite educational TV program were not equal for the variables of location and gender. It was also found that for students, learning demand, learning content, and class management were factors affecting their satisfaction with the satellite educational TV programs. For teachers, learning content and class management were the factors. The statistical mean difference in the satisfaction with the satellite educational TV program was between students and teachers. These findings suggest that the satellite educational TV program has the possibility of improving the quality of education in Ethiopian secondary schools.  相似文献   
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This study explores the impact of governmental support policies on the innovation of SMEs in the regional strategic industries in South Korea. We use the technological development assistance funds as a proxy for governmental support policies for SMEs in the regional industries in Korea. The innovation of SMEs is measured by technological innovation: patent, utility model, trademark, and new design registrations. Before empirically testing the impact of governmental support policies on the innovation of SMEs, this study reviews the literature concerning the innovation and the governmental support policies of SMEs in regional industries. Results from empirical models, which simultaneously control for factors which were thought to affect the innovation of regional SMEs, indicate that a positive relationship exists among the technological development assistance by the Korean government and patent acquisitions and new design registrations of regional SMEs. Networks with universities also have a positive relationship with patent acquisitions and new design registrations of regional SMEs. This study suggests there is an importance to governmental financial aids for regional SME innovations, and there is an importance to the need to build a strong social relationship in today's networked economy.  相似文献   
77.
This paper reports a method to control the fluid flow in paper-based microfluidic devices simply by pressing over the channel surface of paper, thereby decreasing the pore size and permeability of a non-woven polypropylene sheet. As a result, fluid resistance is increased in the pressed region and causes flow rate to decrease. We characterize the decrease of flow rate with respect to different amounts of pressure applied, and up to 740% decrease in flow velocity was achieved. In addition, we demonstrate flow rate control in a Y-shaped merging paper and sequential delivery of multiple color dyes in a three-branched paper. Furthermore, sequential delivery of multiple fluid samples is performed to demonstrate its application in multi-step colorimetric immunoassay, which shows a 4.3-fold signal increase via enhancement step.  相似文献   
78.
We present an optofluidic microvalve utilizing an embedded, surface plasmon-enhanced fiber optic microheater. The fiber optic microheater is formed by depositing a titanium thin film on the roughened end-face of a silica optical fiber that serves as a waveguide to deliver laser light to the titanium film. The nanoscale roughness at the titanium-silica interface enables strong light absorption enhancement in the titanium film through excitation of localized surface plasmons as well as facilitates bubble nucleation. Our experimental results show that due to the unique design of the fiber optic heater, the threshold laser power required to generate a bubble is greatly reduced and the bubble growth rate is significantly increased. By using the microvalve, stable vapor bubble generation in the microchannel is demonstrated, which does not require complex optical focusing and alignment. The generated vapor bubble is shown to successfully block a liquid flow channel with a size of 125 μm × 125 μm and a flow rate of ∼10 μl/min at ∼120 mW laser power.  相似文献   
79.
A new distributed fusion receding horizon filtering problem is investigated for uncertain linear stochastic systems with time-delay sensors. First, we construct a local receding horizon Kalman filter having time delays (LRHKFTDs) in both the system and measurement models. The key technique is the derivation of recursive error cross-covariance equations between LRHKFTDs in order to compute the optimal matrix fusion weights. It is the first time to present distributed fusion receding horizon filter for linear discrete-time systems with delayed sensors. It has a parallel structure that enables processing of multisensory time-delay measurements, so the calculation burden can be reduced and it is more reliable than the centralized version if some sensors turn faulty. Simulations for a multiple time-delays system show the effectiveness of the proposed filter in comparison with centralized receding horizon filter and non-receding versions.  相似文献   
80.
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   
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