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51.
This study examines US and South Korean journalists' use of sources and their perceptions of source credibility in covering the six-party talks on North Korea's nuclear ambitions. In particular, this study analyzes the relationship between journalists' perceptions of source credibility and the media's source use in terms of the aggregate and individual levels. Results of content analysis of US and South Korean newspapers are compared with data from a survey of US and South Korean journalists who covered the six-party nuclear talks. Government officials are dominant sources in media coverage of the talks because of their high level of accessibility and credibility. US and South Korean journalists assigned the greatest credibility to government officials of their own country. The two groups showed significant differences in their perceptions of credibility of South Korean officials, North Korean officials, Japanese officials, and Japanese experts. Moreover, this study finds that individual journalists' perceptions of source credibility were as strongly correlated with their individual use of sources as with the news media's aggregate use of sources. Implications of the findings are discussed in the context of media sociology, in particular gatekeeping.  相似文献   
52.
The bubble-free and pulse-free fluid delivery is critical to reliable operation of microfluidic devices. In this study, we propose a new method for stable bubble-free and pulse-free fluid delivery in a microfluidic device. Gas bubbles are separated from liquid by using the density difference between liquid and gas in a closed cavity. The pulsatile flow caused by a peristaltic pump is stabilized via gas compressibility. To demonstrate the proposed method, a fluidic chamber which is composed of two needles for inlet and outlet, one needle for a pinch valve and a closed cavity is carefully designed. By manipulating the opening or closing of the pinch valve, fluids fill up the fluidic chamber or are delivered into a microfluidic device through the fluidic chamber in a bubble-free and pulse-free manner. The performance of the proposed method in bubble-free and pulse-free fluid delivery is quantitatively evaluated. The proposed method is then applied to monitor the temporal variations of fluidic flows of rat blood circulating within a complex fluidic network including a rat, a pinch valve, a reservoir, a peristaltic pump, and the microfluidic device. In addition, the deformability of red blood cells and platelet aggregation are quantitatively evaluated from the information on the temporal variations of blood flows in the microfluidic device. These experimental demonstrations confirm that the proposed method is a promising tool for stable, bubble-free, and pulse-free supply of fluids, including whole blood, into a microfluidic device. Furthermore, the proposed method will be used to quantify the biophysical properties of blood circulating within an extracorporeal bypass loop of animal models.  相似文献   
53.
The purpose of this study was to analyze the effects of collaborative activities on group identity in a virtual world such as Second Life. To achieve this purpose, this study adopted events that promoted participants' interactions using tools inherent in Second Life. The interactive tools given to the control group in this study included ‘permissions to move, copy, edit’, ‘give item’, ‘chat’, and ‘send instant message’. In addition to these tools, special tools of ‘give item for praise’ and ‘pollster’ were given to the experimental group. The two groups were compared using scores of group identity, which has nine subcategories. The experimental group showed higher scores in five subcategories than the control group. Thus, we concluded that the use of tools for facilitating participants' interactions is effective for the formation of group identity.  相似文献   
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55.
The development and current status of special education in South Korea are described and contrasted to that of the United States. South Korean special education was initiated in the 1890s by U.S. missionaries. Later, Japanese influence was considerable, especially on its regular educational programs. Special programs are available for five classifications of disabilities. Its major national special education legislation contains numerous provisions similar to P.L. 94-142. However, various conditions may impede the further development of services, including a high teacher-pupil ratio, the reliance on self-contained programs, negative attitudes toward people with disabilities, and lack of advocacy groups. Further initiatives require considerable research and policy debate among South Koreans.  相似文献   
56.
Automatic text classification is the problem of automatically assigning predefined categories to free text documents, thus allowing for less manual labors required by traditional classification methods. When we apply binary classification to multi-class classification for text classification, we usually use the one-against-the-rest method. In this method, if a document belongs to a particular category, the document is regarded as a positive example of that category; otherwise, the document is regarded as a negative example. Finally, each category has a positive data set and a negative data set. But, this one-against-the-rest method has a problem. That is, the documents of a negative data set are not labeled manually, while those of a positive set are labeled by human. Therefore, the negative data set probably includes a lot of noisy data. In this paper, we propose that the sliding window technique and the revised EM (Expectation Maximization) algorithm are applied to binary text classification for solving this problem. As a result, we can improve binary text classification through extracting potentially noisy documents from the negative data set using the sliding window technique and removing actually noisy documents using the revised EM algorithm. The results of our experiments showed that our method achieved better performance than the original one-against-the-rest method in all the data sets and all the classifiers used in the experiments.  相似文献   
57.
ABSTRACT: A Web-based interdisciplinary instructional resource was developed to provide information that will increase food science educators' knowledge of waste management in the food chain. The 4 modules are: legal implications for management of wastes/residues; identification, quantification, and characterization of wastes/residues; management of wastes/residues; and economic ramifications of wastes/residues. Instructional materials are available for faculty and GTAs for use in teaching the 4 modules. Food science educators can use this Web-based instructional tool as an educational resource in their undergraduate classes to enhance students' knowledge and ability to solve critical environmental problems in the food chain. See http://www.oznet.ksu.edu/swr/home/welcome.htm  相似文献   
58.
We report a refillable and valveless drug delivery device actuated by an external magnetic field for on-demand drug release to treat localized diseases. The device features a pear-shaped viscoelastic magnetic membrane inducing asymmetrical deflection and consecutive touchdown motion to the bottom of the dome-shaped drug reservoir in response to a magnetic field, thus achieving controlled discharge of the drug. Maximum drug release with 18 ± 1.5 μg per actuation was achieved under a 500 mT magnetic flux density, and various controlled drug doses were investigated with the combination of the number of accumulated actuations and the strength of the magnetic field.  相似文献   
59.
Herein, we present a large-area 3D hemispherical perforated microwell structure for a bead based bioassay. Such a unique microstructure enables us to perform the rapid and stable localization of the beads at the single bead level and the facile manipulation of the bead capture and retrieval with high speed and efficiency. The fabrication process mainly consisted of three steps: the convex micropatterned nickel (Ni) mold production from the concave micropatterned silicon (Si) wafer, hot embossing on the polymer matrix to generate the concave micropattened acrylate sheet, and reactive ion etching to make the bottom holes. The large-area hemispherical perforated micropatterned acrylate sheet was sandwiched between two polydimethylsiloxane (PDMS) microchannel layers. The bead solution was injected and recovered in the top PDMS microchannel, while the bottom PDMS microchannel was connected with control lines to exert the hydrodynamic force in order to alter the flow direction of the bead solution for the bead capture and release operation. The streptavidin-coated microbead capture was achieved with almost 100% yield within 1 min, and all the beads were retrieved in 10 s. Lysozyme or thrombin binding aptamer labelled microbeads were trapped on the proposed bead microarray, and the in situ fluorescence signal of the bead array was monitored after aptamer-target protein interaction. The protein-aptamer conjugated microbeads were recovered, and the aptamer was isolated for matrix assisted laser desorption/ionization time-of-flight mass spectrometry analysis to confirm the identity of the aptamer.  相似文献   
60.
The Supports Intensity Scale–Children's Version (SIS‐C) was developed to assess the support needs of children and youth aged 5 to 16 years with intellectual and developmental disabilities. Data from the standardization sample of the SIS‐C were analyzed to evaluate the impact of the age cohorts (5–6, 7–8, 9–10, 11–12, 13–14, and 15–16 years) used to stratify the sample on the measurement model, as well as the latent means, standard deviations, and correlations. The findings confirmed measurement invariance across age cohorts, but suggested that at the latent level, younger children, generally, have more intensive support needs and that as students with intellectual disability age, their support needs decrease. In addition, the 15‐ to 16‐year‐old cohort displayed differences in terms of the strength of correlations between support need domains, with stronger correlations than the other age groups. Implications for future research and practice are described.  相似文献   
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