• Journal of KIISE:Databases
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• v.29 no.2
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• pp.119-127
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• 2002

Video server which stores video streams should serve more users with the requested streams rapidly, satisfying their time constraints. However, the number of users supported and the response times for the requested services in video server are in the oppositional relationship with viewpoint of disk throughput. In this paper, we propose new policy that can provide not only rapid responses for the service requests but also increase the number of users supported in the storage system of video server. The policy admits the random movements of disk heads for urgent service requests but maintains the sequential or restricted movements of disk heads and eliminates rewind time of disk heads for less-urgent service requests in storage system of multiple disks environment so that it can not satisfy only the QoS of users but also support more users.

• Journal of Korean Public Health Nursing
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• v.14 no.1
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• pp.68-79
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• 2000

In order to provide a desirable direction for the health education on preventing drinking of elementary school students. by understanding the views held by elementary school teachers on drinking prevention education. 529 teachers at elementary schools located in Seoul were responded by constructed questionnaires during the period of Nov. 15 to Dec. 18 1999. The results of the survey analysis were as follows: 1. $84.6\%$ of the respondents said that schools should offer education programs on preventing drinking, and this view was more strongly shared by teachers with religions than non-religious ones. 2. $35.0\%$ of teachers responded that the education should start with 6th graders, while $28.3\%$ opted for 4th to 5th grades. With regard to the appropriate class in providing such education, $41.0\%$ selected physical education (PE), followed by extracurricular activity class with $35.4\%.\; 45.6\%$ of the respondents said discussion would be the most effective education method. while $35.4\%$ recommended using experiments. Growth and developmental defect and fall in diseases were pointed out as the most interesting topic for students by $39.4%$ and $31.2\%$ of the surveyed, respectively. As for the most effective media for education, $56.0\%$ recommended video, followed by cartoons $(21.5\%)$ and computer games $(19.5\%),\;63.7\%$ of the teachers picked school nurses as the most appropriate person in carrying out the education. The results of the finding show that it would be most desirable to provide health education on preventing drinking to senior elementary schoolers during the PE or extracurricular activity class by school nurses. The program would be structured to first show video clips on growth and developmental defect or fall in diseases resulting from drinking and to have discussions or experiments on related matters.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.5
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• pp.127-135
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• 2010

In motion adaptive temporal noise reduction filtering used for reducing video noises, the strength of motion adaptive temporal filtering should be carefully controlled according to temporal movement. This paper presents a motion adaptive temporal filtering scheme based on least-square training. Each pixel is classified to a specific class code according to temporal movement, and then, an iterative least-square training method is applied for each class code to find optimal filtering coefficients. The iterative least-square training is an off-line procedure, and the trained filter coefficients are stored in a lookup table (LUT). In actual noise reduction filtering operation, after each pixel is classified by temporal movement, simple filtering operation is applied with the filter coefficients stored in the LUT according to the class code. Experiment results show that the proposed method efficiently reduces video noises without introducing blurring.

• Child Health Nursing Research
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• v.6 no.3
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• pp.305-315
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• 2000

In order to provide a desirable direction for the health education on preventing smoking of elementary school students, by understanding the views held by elementary school teachers on smoking prevention education, 529 teachers at elementary schools located in Seoul were responded by constructed questionnaires during the period of Nov. 15 to Dec. 18 1999. The results of the survey analysis were as follows: 1. 91.9% of the respondents said that schools should offer education programs on preventing smoking, and this view was more strongly shared by teachers with religions than non-religious ones. 2. 37.6% of teachers responded that the education should start with 4th-5th graders, while 36.0% opted for 6th grades. With regard to the appropriate class in providing such education, 41.1% selected physical education (PE), followed by extracurricular activity class with 28.8%, 45.1% of the respondents said discussion would be the most effective education method, while 39.9% recommended using experiments. fall in diseases and growth and developmental defect were pointed out as the most interesting topic for students by 33.2% and 28.1% of the surveyed, respectively. As for the most effective media for education, 57.2% recommended video, followed by computer games(19.2%) and cartoons (20.0%). 64.1% of the teachers picked school nurses as the most appropriate person in carrying out the education. The results of the finding show that it would be most desirable to provide health education on preventing smoking to senior elementary schoolers during the PE or extracurricular activity class by school nurses. The program would be structured to first show video clips on growth and developmental defect or fall in diseases resulting from smoking and to have discussions or experiments on related matters.

• Journal of Korean Elementary Science Education
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• v.37 no.2
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• pp.206-218
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• 2018

The purpose of this study is to analyze the teaching behaviors and visual attention according to teacher's career in Elementary Science Inquire-based Class. Participants were four elementary school teachers in Seoul. They were all in grade 5 and taught science. According to the experience of elementary science education, two novice teachers and two expert teachers were identified. Participants taught Respiration in the 'Structure and Function of our Body' in the elementary science fifth grade. The mobile eye tracker used in this study is SMI's ETG 2w, which is a binocular tracking system. In addition, a video camera was installed behind the classroom to record the entire class. We recorded all the contents of the recorded video and analyzed the results. In this study, the actual practice time, participant's visual attention, and decentralized attention ability were analyzed by class phase. The results of the study are as follows. First, there was a difference between planned class time and actual practice time. The novice teachers were having difficulty in reconstructing the contents of education, and the expert teachers were reconstructing the curriculum and interacting with the students with high understanding and application of the curriculum. There were many differences between the novice teachers and the expert teachers in the tour guidance to confirm student activities. Second, if we look at the visual attention on the area related to teaching and learning by class phase, the novice teacher concentrates all the steps in a specific area, expert teachers showed an equal visual attention to meaningful areas of teaching and learning activities. Third, there was a statistically significant difference in activities 1-1, 1-2, 2-1, and 2-2 when the participants' decentralized attention ability. Expert teachers frequently checked students' understanding and interests. There was a lot of interaction with students. It is also shown through the decentralized attention ability that the novice teachers concentrate on a specific area, and the expert teachers have a high degree of decentralized attention ability and visual attention evenly.

• Journal of The Korean Association For Science Education
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• v.30 no.6
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• pp.836-849
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• 2010

The purpose of this study is to analyze changes of competency observed in teaching of pre-service science teachers through the teaching evaluation and reflective journal writings on science class during the period of student-teaching at high school. To do this, we videotaped all the science classes of six pre-service teachers participating in this study, evaluated their class teachings, and collected moving video clips recorded in their classes, reflective journals, interviews, instructional materials, and teaching evaluation they have provided. From the "Standards for teaching evaluation of science instruction" developed by Korea Education Curriculum and Assessment, sixteen evaluation elements were selected and used for the analysis. According to our results, all preservice teachers show improvement of teaching performance in most of the class evaluation elements as the number of science classes increases. They presented the lowest improvement in the 'to design meaningful learning program,' which was one of the sixteen elements. However, there are substantial individual differences in the pre-service teachers' teaching competence on each evaluation element. Although they thought that 'understanding of scientific concepts' is the most important part of a science class in the beginning of student-teaching training, they showed changes in recognition that 'interaction and respect' and 'managing student behaviors' are also important in the end. They have recognized that writing a reflective journal, based on the video clips recorded in class and teaching evaluation, helps improve their teaching competency. In addition, improvement in teaching competency has influence upon career-orientation towards the school teacher in the future.

• Korean Association of Arts Management
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• no.53
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• pp.207-247
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• 2020

is a project for the senior generation with humanistic knowledge to become a mentor and communicate with them to present the wisdom and direction of life to the new generations of mentees based on various life experiences. has been expanding since 2015, starting with the pilot operation in 2014. In general, projects such as these are assessed to establish effectiveness indicators to verify effectiveness and to establish project management and development strategies. However, most of the evaluations have been conducted quantitatively and qualitatively based on the short-term duration of the project. Therefore, in the case of continuous projects such as , especially in the field of culture and arts where long-term effectiveness verification is required, the short-term evaluation is difficult to predict and judge the actual meaningful effects. In this regard, tried to examine the qualitative change of key participants in this project through the 2017 and 2018 image tracking survey. For this purpose, we adopted qualitative research methodology through interview video shooting, field shooting, and value coding as a research method suitable for the research subject. To analyze the results, first, the interview images were transcribed, keywords were extracted, value encoding works were matched with human psychological values, and the theoretical method was used to identify changes and to derive the meaning. In fact, despite the fact that the study conducted in this study was a follow-up survey, it remained a limitation that it analyzed the changed pattern in a rather short time of 2 years. However, this study systemized the specific methodology that researchers should conduct for follow-up and provided the flow of research at the present time when there is hardly a model for follow-up in the field of culture and arts education business in Korea as well as abroad. Significance can be derived from this point. In addition, it can be said that it has great significance in preparing the detailed system and case of comparative analysis methodology through value coding.

• Journal of the Korean Chemical Society
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• v.64 no.1
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• pp.38-48
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• 2020

The purpose of this study was to analysis characteristics and changes of epistemic thinking in middle school students on class-argument activities in an argument-based inquiry(ABI) science class. Data was collected from class recording video and activity worksheets of five subjects argument-based inquiry. Results of the analysis of student epistemic cognition characteristics show that experimental data was presented the most as evidence, and depending on the ABI activity, personal experience-based evidence and evidence based on scientific principles were used. As a result of analyzing the changes between claims made before and after class argumentations on five ABI activities in an argument-based inquiry science class, student claim modifications could be classified, according to reasons for the modification, into three types: correcting incorrect claims, clarifying unclear content, and expanding the concept.

• Journal of Korean Elementary Science Education
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• v.36 no.4
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• pp.303-315
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• 2017

The purpose of this study is to analyze elementary teachers' science class objectively and quantitatively using Mobile Eye Tracker. The mobile eye tracker is easy to wear in eyeglasses form. And experiments are collected in video form, so it is very useful for realizing objective data of teacher's class situation in real time. Participants in the study were 2 elementary teachers, and they are teaching sixth grade science in Seoul. Participants took a 40-minute class wearing a mobile eye tracker. Eye movements of participants were collected at 60 Hz, and the collected eye movement data were analyzed using SMI BeGaze 3.7. In this study, the area related to the class was set as the area of interest, we analyzed the visual occupancy of teachers. In addition, we analyzed the linguistic interaction between teacher and students. The results of the study are as follows. First, we analyze the visual occupancy of meaningful areas in teaching-learning activities by class stage. Second, the analysis of eye movements when teachers interacted with students showed that teacher A had a high percentage of students' faces, while teacher B had a high visual occupation in areas not related to classes. Third, the linguistic interaction of the participants were analyzed. Analysis areas include questions, attention-focused language, elementary science teaching terminology, daily interaction, humor, and unnecessary words. This study shows that it is possible to analyze elementary science class objectively and quantitatively through analysis of visual occupancy using mobile eye tracking. In addition, it is expected that teachers' visual attention in teaching activities can be used as an index to analyze the form of language interaction.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.3 no.6
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• pp.575-596
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• 2009

Facing limited network resources such as bandwidth and processing capability, the Internet will have congestion from time to time. In this paper, we propose a scheme to maximize the total utility offered by the network to the end user during congested times. We believe the only way to achieve our goal is to make the scheme application-aware, that is, to take advantage of the characteristics of the application. To make our scheme scalable, it is designed to be class-based. Traffic from applications with similar characteristics is classified into the same class. We adopted the RED queue management mechanism to adaptively control the traffic belonging to the same class. To achieve the optimal utility, the traffic belonging to different classes should be controlled differently. By adjusting link bandwidth assignments of different classes, the scheme can achieve the goal and adapt to the changes of dynamical incoming traffic. We use the control theoretical approach to analyze our scheme. In this paper, we focus on optimizing the control on two types of traffic flows: TCP and Simple UDP (SUDP, modeling audio or video applications based on UDP). We derive the differential equations to model the dynamics of SUDP traffic flows and drive stability conditions for the system with both SUDP and TCP traffic flows. In our study, we also find analytical results on the TCP traffic stable point are not accurate, so we derived new formulas on the TCP traffic stable point. We verified the proposed scheme with extensive NS2 simulations.