• Journal of the Korean Society of Radiology
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• v.17 no.1
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• pp.141-148
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• 2023

The algebraic reconstruction technique is one of the reconstruction methods in CT and shows good image quality against noise-dominant conditions. The number of iteration is one of the key factors determining the execution time for the algebraic reconstruction technique. However, there are some rules for determining the number of iterations that result in more than a few hundred iterations. Thus, the rules are difficult to apply in practice. In this study, we proposed a method to determine the number of iterations for practical applications. The reconstructed image quality shows slow convergence as the number of iterations increases. Image quality 𝜖 < 0.001 was used to determine the optimal number of iteration. The Shepp-Logan head phantom was used to obtain noise-free projection and projections with noise for 360, 720, and 1440 views were obtained using Geant4 Monte Carlo simulation that has the same geometry dimension as a clinic CT system. Images reconstructed by around 10 iterations within the stop condition showed good quality. The method for determining the iteration number is an efficient way of replacing the best image-quality-based method, which brings over a few hundred iterations.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.3
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• pp.316-326
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• 2009

Recently, local foods have drawn significant attention due to their intrinsic merits. Such foods not only have commercial potential, but also cultural value. Therefore, local foods must be well-maintained and fostered, and a comprehensive plan to develop them must be devised. In this aspect, various factors such as dietary attitudes, perceptions and concerns affecting their development should be considered. The present study was designed to investigate via survey the dietary attitudes, perceptions and concerns towards local foods among married women in Jeollabuk-do. The number of subjects was 434. According to the results, the highest frequency for consuming local foods was '1~3 times/month' for all ages. For the number of local foods subjects had ever tried, '7~8' was the highest overall with 36.8%, followed by '5~6', '3~4', '9~10', and '0~2' with 27.4%, 17.9%, 10.3% and 7.6%, respectively. However, there was a statistically significant difference according to age. The higher the person’s age, the higher the number of local foods they had tried. A similar pattern was shown in the number of local foods subjects had ever cooked. For those in their 20s and 30s, the highest number was '0~2', with 70.8% and 53.0%, respectively, while for those in their 40s the highest number was '3~4' with 38.5%, and for those above 50s it was '5~6' with 31.4%. Most of the subjects realized the need to advance the development of local foods. There were differences among the subjects for certain aspects concerning progression and development, opinions on the major drawbacks of local food development items served more often at home, and different views by age on taste modifications according to modern concepts. From this study, it can be concluded that the utilization of local foods increases with age, and the view that local food development should be based on the recovery and/or maintenance of original tastes becomes more prevalent with age.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.11B
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• pp.1303-1310
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• 2009

Glassless 3D display requires multiple images taken from different viewpoints to show a scene. The simplest way to get multi-view image is using multiple camera that as number of views are requires. To do that, synchronize between cameras or compute and transmit lots of data comes critical problem. Thus, generating such a large number of viewpoint images effectively is emerging as a key technique in 3D video technology. Image-based view synthesis is an algorithm for generating various virtual viewpoint images using a limited number of views and depth maps. In this paper, because the virtual view image can be express as a transformed image from real view with some depth condition, we propose an algorithm to compute multi-view synthesis from two reference view images and their own depth-map by stepwise duplex forward mapping. And also, because the geometrical relationship between real view and virtual view is repetitively, we apply our algorithm into OpenGL Shading Language which is a programmable Graphic Process Unit that allow parallel processing to improve computation time. We demonstrate the effectiveness of our algorithm for fast view synthesis through a variety of experiments with real data.

• Journal of Society of Preventive Korean Medicine
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• v.9 no.1
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• pp.91-103
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• 2005

The purpose of this study was to find out the various opinions of Oriental Medical Doctors to give the recommendations for making the proper policy of the supply and demand of Oriental Medical specialist. This study was desinged of 480 doctors who answered about questions that is composed of 105 Oriental medical specialist, 227 Apprentice doctor and 148 Oriental Medical doctors. On the assumption that there are many different situations and visions about the Oriental medical specialty system, we wanted to know about the each situations and visions about oriental specialty system. Generally, as one grows older, they adapted high proportion about the propriate number of specialist. About this difference from each generations, we can explain that young doctors more worry about the supply of specialist. As well each achievement, the more higher achievement, the more higher proportions of specialist is adapted. Answers about the number of present specialist, the more aging the more negative response about the number of present, number of specialist, this is because of the proprotions who wanted to be a specialist in open doctors. About the property of the number of specialist, there are many different views in each other groups. Anyway it is important that hearing the opinion of each Oriental Medical Doctors for the better Oriental Medical System.

• Journal of Korean Elementary Science Education
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• v.36 no.1
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• pp.95-112
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• 2017

The competence of teachers, comes out through their lesson, is one of the key factors of school education. The purpose of this study is comparing the viewpoints on the science lessons in the elementary classrooms between pre-service teachers and highly experienced teachers in order to draw implications on pre-service teacher educating system. The participants of the study are 14 junior students in a university of education and 9 elementary school teachers who are highly educated and have much career experience. Each student participant observed one video clip with science lesson of their classmate. The total number of the video subject to observation is 4. Meanwhile experienced teachers observed 1 or 2 videos which are the same to those the students watched. The participants made a class criticism according to the General Standards for Class Critique made by KICE. The in-depth analysis of the criticism yielded the following conclusions; First, pre-service teachers had narrow views on the science class mainly limited in the practical part of class, but experienced teachers had wide views covered to class-knowledge, plan, and practice. Second, most experienced teachers thought that learning is the process by which students acquire knowledge or concepts by themselves, and the main purpose of the class is to help students' learning. Meanwhile, there were many pre-service teachers who thought that conveying knowledge or concepts to students was the main purpose of the class. Third, experienced teachers thought that a good science class should maintain consistency around the learning goals from the planning, implementation, and evaluation. However, many pre-service teachers did not take the learning objectives so seriously.

• Korean Medical Education Review
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• v.19 no.3
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• pp.158-168
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• 2017

There is a more urgent call for educational methods of machine learning in medical education, and therefore, new approaches of teaching and researching machine learning in medicine are needed. This paper presents a case using machine learning through text analysis. Topic modeling of news articles with the keyword 'asbestos' were examined. Two hypotheses were tested using this method, and the process of machine learning of texts is illustrated through this example. Using an automated text analysis method, all the news articles published from January 1, 1990 to November 15, 2016 in South Korea which included 'asbestos' in the title and the body were collected by web scraping. Differences in topics were analyzed by structured topic modelling (STM) and compared by press companies and periods. More articles were found in liberal media outlets. Differences were found in the number and types of topics in the articles according to the partisanship and period. STM showed that the conservative press views asbestos as a personal problem, while the progressive press views asbestos as a social problem. A divergence in the perspective for emphasizing the issues of asbestos between the conservative press and progressive press was also found. Social perspective influences the main topics of news stories. Thus, the patients' uneasiness and pain are not presented by both sources of media. In addition, topics differ between news media sources based on partisanship, and therefore cause divergence in readers' framing. The method of text analysis and its strengths and weaknesses are explained, and an application for the teaching and researching of machine learning in medical education using the methodology of text analysis is considered. An educational method of machine learning in medical education is urgent for future generations.

• Korean Journal of Social Welfare
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• v.64 no.4
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• pp.5-29
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• 2012

This study aimed to express the experiences of the parents who lost their children by suicides in their own words from their own perspectives by van Manen(2000)'s hermeneutic phenomenological approach. The analysis of the words expressed by the research participants led to the following five fundamental themes. These are 'broken heart, sinner's grief, land of exile and time stood still, pains to be comforted, and days ahead with half-stitched wounds'. Several distinctions are found due to cultural differences from Korean parents. First, whereas the Western parents see the cause of their child's suicide as his/her independent issue, the Korean parents blame themselves entirely. This may have stemmed from the overly inter-dependency between the parents and the child. Second, whereas the Western perspective views the suicide as a type of illness from the individual's depression. The Korean perspective views the suicide as a shame that disgraces the parents or the family. This negative social perspective intensifies the self-blame and social isolation. Third, the Westerners recognize the prevention and responsibility of suicide resting with the society and government, but the Korean society recognize suicide as personal or family matter. Based on the finding above, I proposed a number of practical measures to aid the surviving parents who belong to a group with extremely high suicidal rates.

• The Transactions of the Korea Information Processing Society
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• v.7 no.1
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• pp.215-223
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• 2000

The advancements in technology which have lead to higher and higher levels of integration have required advancements in the methods used in designing VLSI chip. A key to enable a complicated chip design is the use of hierarchy in the design process. Hierarchy organizes the function of a large number of transistors ito a particular, easy-to-manage function. For these reasons, hierarchy has been used in the design process of digital functions for many years. However, there exists differences in a design analysis phase, especially in timing analysis, due to multiple views for the same design. In timing analysis of the hierarchical design, every path is analyzed within partitioned modules independently and the global timing analysis is applied to the whole design considering each module as a single timing component. Therefore, timing results of the hierarchical design could not be same as those of non-hierarchical flat design. In this paper, we formulate the timing problem in the hierarchical design and analyze the possible source of timing differences. We define a new terminology of "consistent result" between different views for the same design. We also propose a new partitioning algorithm to obtain the consistent results. This algorithm helps to enhance the design cycle time.

• Journal of The Geomorphological Association of Korea
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• v.18 no.3
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• pp.1-10
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• 2011

Sanbangsan and Yongmuri Beach as geosites are very wide areas, and tourists have accessed them via various courses; hence the need to double the number of geosite signs and disperse them at each point. The signs should read "Sanbangsan lava dome," "Yongmuri tuff ring," and "Relationship between the Sanbangsan lava dome and Yongmuri tuff ring." The contents of the sign should be systemic, simple, and clear because tourists have to read it in a short time. The viewpoint of the research area can be largely divided into Sanbangsan View, Yongmuri Beach View, Sanbangsan, and Yongmuri Beach View. Three of each viewpoint (total of 9 viewpoints) can be placed. In the geosite of Sanbangsan and Yongmuri Beach are 5 sub-theme views including the boundary sheet of Sanbangsan and Yongmuri tuff ring, xenolith basalt, marine pothole, tafoni, and crossed sedimentary layer. These sub-theme views are important in understating not only the geosite but the overall geopark as well, so they should be developed and utilized aggressively.

• Journal of Broadcast Engineering
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• v.24 no.2
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• pp.273-280
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• 2019

360 video is attracting attention as immersive media with the spread of VR applications, and MPEG-I (Immersive) Visual group is actively working on standardization to support immersive media experiences with up to six degree of freedom (6DoF). In virtual space of omnidirectional 6DoF, which is defined as a case of degree of freedom providing 6DoF in a restricted area, looking at the scene at any viewpoint of any position in the space requires rendering the view by synthesizing additional viewpoints called virtual omnidirectional viewpoints. This paper presents the performance results on view synthesis and their analysis, which have been done as exploration experiments (EEs) of omnidirectional 6DoF in MPEG-I. In other words, experiment results on view synthesis in various aspects of synthesis conditions such as the distances between input views and virtual view to be synthesized and the number of input views to be selected from the given set of 360 videos providing omnidirectional 6DoF are presented.