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51.
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
52.
Literature in the United States provides many examples of no difference in student achievement when measured against the mode of test administration i.e., paper‐pencil and online versions of the test. However, most of these researches centre on ‘regular’ students who do not require differential teaching methods or different evaluation processes and techniques. This research provides evidence that students who have learning disabilities, like their counterparts in the regular educational programme, do not lag behind in computer adaptation and use. The study, using differential item functioning analysis with an ‘external’ variable and an analysis of covariance, shows that items and tests can be created to have no practical differences in the mode of administration for this special group of students, and as such, is in keeping with the trend for using online testing with its many advantages (cost savings, flexibility in administration, etc.) in lieu of the paper and pencil version of the test. 相似文献
53.
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
54.
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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56.
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
57.
C.W. Shanklin H. Huang Kyung-Eun Lee C. Ok S. Seo S.A. Flores 《Journal of Food Science Education》2003,2(3):47-52
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.
Word sense disambiguation (WSD) is meant to assign the most appropriate sense to a polysemous word according to its context. We present a method for automatic WSD using only two resources: a raw text corpus and a machine-readable dictionary (MRD). The system learns the similarity matrix between word pairs from the unlabeled corpus, and it uses the vector representations of sense definitions from MRD, which are derived based on the similarity matrix. In order to disambiguate all occurrences of polysemous words in a sentence, the system separately constructs the acyclic weighted digraph (AWD) for every occurrence of polysemous words in a sentence. The AWD is structured based on consideration of the senses of context words which occur with a target word in a sentence. After building the AWD per each polysemous word, we can search the optimal path of the AWD using the Viterbi algorithm. We assign the most appropriate sense to the target word in sentences with the sense on the optimal path in the AWD. By experiments, our system shows 76.4% accuracy for the semantically ambiguous Korean words. 相似文献
59.
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
60.
Young-Pyo Seo 《Inter-Asia Cultural Studies》2017,18(2):197-217
This paper discusses the legacy of Stuart Hall’s cultural studies approach to socialist politics. Like many other socialist thinkers, his ideas are the direct outcome of political intervention, often through the form of theoretical practice. Because gaps will always remain between reality and theoretical explanation, political intervention tends to be an overreaction to social change or the underestimation of people’s power. Hall’s political practice cannot therefore be exceptional in that it is far from perfect. This paper attempts to establish a balance sheet in terms of his involvement in the debate on the nature of British society, Thatcherism and neo-liberalism. From this examination, some key concepts will be employed to analyse the nature of Korean society in relation to neo-liberal restructuration and the neo-liberal historic bloc. Discussing Hall’s ideas and applying these to Korea, the paper sets out to demonstrate both weaknesses and strengths in Hall’s thought. The strength consists of his open-ended and empirically sensitive reformation of Marxism. On the other hand, the core weakness is found in his post-Marxist epistemological relativism. The main argument set out here is that, in order to develop and refine Hall’s thought, there should be an ontologically realist position compatible with epistemological relativism. For this difficult task, the concept of needs can be suggested as a fresh starting point. 相似文献