• Progress in Medical Physics
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• v.26 no.3
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• pp.143-152
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• 2015

In this study, we aim to design the architecture of the kV imaging system for tumor tracking in the dual-head gantry system and analyze its accuracy by simulations. We established mathematical formulas and algorithms to track the tumor position with the two-pair kV imaging systems when they are in the non-orthogonal positions. The algorithms have been designed in the homogeneous coordinate framework and the position of the source and the detector coordinates are used to estimate the tumor position. 4D XCAT (4D extended cardiac-torso) software was used in the simulation to identify the influence of the angle between the two-pair kV imaging systems and the resolution of the detectors to the accuracy in the position estimation. A metal marker fiducial has been inserted in a numerical human phantom of XCAT and the kV projections were acquired at various angles and resolutions using CT projection software of the XCAT. As a result, a positional accuracy of less than about 1mm was achieved when the resolution of the detector is higher than 1.5 mm/pixel and the angle between the kV imaging systems is approximately between $90^{\circ}$ and $50^{\circ}$. When the resolution is lower than 1.5 mm/pixel, the positional errors were higher than 1mm and the error fluctuation by the angles was greater. The resolution of the detector was critical in the positional accuracy for the tumor tracking and determines the range for the acceptable angle range between the kV imaging systems. Also, we found that the positional accuracy analysis method using XCAT developed in this study is highly useful and will be a invaluable tool for further refined design of the kV imaging systems for tumor tracking systems.

• Journal of Korean Home Economics Education Association
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• v.29 no.2
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• pp.1-22
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• 2017

The purpose of this research is to share the experience of reflective practice of a Home Economics teacher professional learning community(PLC) operator and to share better suggestions through reflection on PLC operation. All conversation in the 18 sessions of the PLC totally from May 31st 2013 to May 19th 2014 was recorded and transcribed. All materials of PLC activity were qualitatively analysed. Its themes were grounded on its coding and categorization scheme. Findings and conclusions of this study are as followings. The experience of learning the PLC for a year has found that it is the power to keep the PLC alive: courage and anxiety to face anxiety and anxiety about new challenges, the importance of theme selection, a teacher with a reckless challenge, shares of becoming a leader. Through reflection, I learned that concerns require attention to other teachers and the need for a 'New Round' for ongoing meetings. I, as a operator, did not fully consider participant's different interest as well as a program for a new round due to the lack of management experience. It led to the low participations in latter sessions of PLC. Suggestions are put as solutions to improve these problems; (1) grouping participants by school levels when collecting participants, (2) setting operation period and program applying participants' opinions, and (3) operating short-term PLC with certain themes to immerse reaching goal and satisfaction in short time.

• Journal of the Korean earth science society
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• v.22 no.6
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• pp.469-479
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• 2001

This study investigated the trends in the number of applicants and mean score and applicants’ responses on the test items of Earth Science in the College Scholastic Ability Test (CSAT) implemented for 3 years (1999-2001). The percentage of applicants of science track were 43.14% in 1995, but reduced through 29.5% in 2001 to 26.92% in 2002 CSAT For elective subject, about 22% of science track students applied to Earth Science II which ranked third to Biology II and Chemistry II. In 1999, test items were developed to have the expected difficulty 40 ${\sim}$ 59% (6 items) to 60 ${\sim}$ 79% (10 items). But in 2001 every 16 items were developed to have difficulty 60 ${\sim}$ 79%, which was caused by the policy of so called ‘easy CSAT’. Thus the mean score of ‘Earth Science II’ was increased from 50.26 in 1999 through 64.47 in 2000, to 67.58 in 2001. Applicants were generally very good at solving test items focusing on process skills only and familar items but poor at solving test items related to the motion of the earth and planets and sea wave, especially items calling two or more concepts. Thus special measures to cope with the decrease in applicants of science track should be provided. And it is recommended to develop test items with wider range of difficulty and to reduce test items calling process skills only. And special consideration should be given to teaching the content area with poor achievement and high actual difficulty compared to the expected.

• The Korean Journal of Financial Management
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• v.10 no.1
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• pp.249-280
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• 1993

Recent financial theory views insurance policies as financial instruments that are traded in markets and whose prices reflect the forces of supply and demand. This article analyzes individual's insurance purchasing behavior along with capital market investment activities, which will provide a more realistic look at the tradeoff between insurance and investment in the individual's budget constraint. It is shown that the financial economic concept of insurance cost should reflect the opportunity cost of insurance premium. The author demonstrates the importance of riskless and risky financial assets in reaching an equilibrium insurance premium. In addition, the paper also investigates how the investment income could affect the four established theorems on traditional insurance literature. At the present time in Korea, the price deregulation is being debated as the most important current issue in insurance industry. In view of the results of this paper, insurance companies should recognize investment income in pricing their coverage if insurance prices are deregulated. Otherwise. price competition may force insurance companies to restrict coverage or to leave the market.

• Journal of The Korean Association For Science Education
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• v.22 no.4
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• pp.706-716
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• 2002

The purpose of this study was to compare and analyze the science process skills and teaching methods between the 6th and the 7th elementary school science textbooks. For this study, science textbooks and teacher's guidebooks from the 3rd to the 6th grade were analyzed. In this research the science process skills are divided by basic process skills(BPS) and integrated process skills(IPS). The BPS is composed of observing, classifying, measuring, predicting and inferring skill, which are 5 subcategories. The IPS is composed of problem cognition, formulating hypothesis, controlling variables, transforming data, interpreting data, drawing result, and generalization, which are 7 subcategories. The results found in the analysis of science process skills in the 6th and 7th science textbooks are as follows: 1. The percentage of the BPS was increased, but the IPS was decreased in the 7th than the 6th. 2. The percentage of the IPS was higher than the BPS in the 6th science textbooks, but the BPS was higher than IPS in lower grade and the IPS was higher than the BPS in higher grade in the 7th textbooks. 3. Observing and problem cognition skill were most dominant in the 6th and 7th science textbooks. 4. The percentages of observing(24.8%), classifying(5.4%), measuring(5.6%), inferring(6.0%) in the BPS and interpreting data(4.4%) in the IPS were increased, but predicting(3.8%), formulating hypothesis(0.5%), controlling variables( 1.8%), transforming data( 1.2%), drawing result(0.8%) and generalization(0.9%) skills were decreased in the 7th. And teaching methods suggested in the curriculum are as follows: the percentages of learning by observation(19.2%) and role play(0.1 %) were decreased, but learning by experiment(6.2%), learning by discussion(2.0%), learning by investigation(4.6%) and creative learning(6,4%) were increased in the 7th than the 6th. In conclusion, it was found that the basic process skills were emphasized in the 7th science textbooks than the 6th and the science process skills in the science textbooks of the 7th curriculum were distributed by the grade level of the elementary children.

• Journal of Environmental Policy
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• v.8 no.2
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• pp.25-61
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• 2009

These days, environmental policies have changed from being command and control systems toward economic incentive systems, with various incentives having been established by OECD countries. In Korea, many environmental charges have been established in order to diminish activities which damage natural resources. Among them, the Ecosystem Conservation Cooperation Charge and the Replacement Charge for Forest Resources Creation are considered to be representative environmental charges. These charges, along with a few others, were designed to encourage efforts to protect natural resources. The charges include a number of different features, utilize varying methods, and altered ranges of jurisdiction. However, the charges may pose serious inequity problems in terms of their estimated values and their conditions of reduction and exemption. For instance, although the Ecosystem Conservation Cooperation Charge is a primary charge applied to natural resource damage, the charge does not fully secure its original objectives due to its low levy and limited range of provisions. Moreover, the Replacement Charge for Forest Resources Creation has been criticized because of similar reduction and exemption provisions. Therefore, this study analyzes the inequity problems associated with the charges and proposes solutions. First of all, the Ecosystem Conservation Cooperation Charge should be redesigned in such a way that it reflects the substantial value of natural resource damage through either abrogate or increased maximum limits of the charge. With regard to the Replacement Charge for Forest Resources Creation, the cases and ranges of reduction and exemption provisions should be narrowed. Finally, the charges collected should be expended in conformity with their original objectives, and their expenditure should be restricted to either restoration activities or activities directly related to compensation and mitigation of damaged natural resources.

• The Journal of the Korea Contents Association
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• v.12 no.12
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• pp.605-615
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• 2012

Dance studies inherently have a nature of convergence and integration. Meanwhile, dance studies have extended their realm by investigating dance phenomena from many perspectives which art theories cannot explain. However, the previous and current dance studies are inadequate to explain a confluence society which is characterized as techuim, Interaction, freedom and openness according to the digital revolution. Hence, a result of research trend in domestic dance studies, it is found that dance studies have been studied in four perspectives since the early 2000s: first, a triggering the various studiesa of the convergent and integrative dance; second, an attempt to the convergent and integrative program development research; third, the vitalization of the convergent research on dance digital contents; and fourth, a research on the convergent dance art phenomena. These researches have played an important role in boosting a change in the structure and realm expansion of dance studies that are interdisciplinary research enabling a holistic approach to the integration and convergence between scientific technique, skills of dance art and other studies. However, it should be acknowledged that one problem is the current research development plan or/and research program have very little feasibility and practicality except an interdisciplinary research on the dance digital contents. Therefore, it is suggested for the development of dance studies in the age of convergence as follows: first, a dance convergent study integrated in skills and theories of dance and science that would pave the way for an academic foundation leading to a new humanistic model in the age of convergent; and second, a need for a paradigm shift that theories should be deployed in the scene on a commercial scale in order to produce effectiveness of the interdisciplinary and integrative research on dance studies by turning into a behavioristic research phase. third, it needs to changeover from large scale of convergent performance into small scale of convergent performance based on original idea for accumulation of teachnique research and promotion of dance convergent performance.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.9 no.2
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• pp.233-250
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• 2014

Since 2000, people who lived in the city begin to see returning to farming in a new perspective. People returning to the farming became a trend and therefore, the number of people who are returning to farm are increasing. Because of the concept of take up farming is developing as an idea of establishing a new business, the government agency and the government-related organization are very supportive as the government is interested in the business. The conclusion is below regarding the analysis result In order to receive the analysis of actual proof, we conducted a survey targeting 300 people who returned to farming village in the whole country, excluding Jeju Island from Aug 1st 2013 to Aug 30th 2013. Except uncandidness answers, we used 252 survey results of our sample. Also we used SPSS Wim Ver. 18.0 to draw a conclusion regarding the collected sample. First, regarding of Hypothesis 1 "Personal characteristic will give positive effects in returning to farming village", was partially supportive Second, regarding of Hypothesis 2 "Reason of settling will give positive effects in returning to farming village", was partially supportive Third, regarding of Hypothesis 3 "Geographic characteristics will give positive effects in returning to farming village", was partially supportive Fourth, the effect of social support between the individual characteristic, reason of settling, and geographic characteristics, the result indicated that the social support was partially supportive in farm returners regarding reason of settlement. However, there were no social support effect in returning to farm satisfaction regarding of geographic characteristic. Fifth, after analysing the difference of personal characteristic regarding demographic characteristic, reason of settlement, and geographic characteristic, the result indicated that people who are age 40+, who graduated graduate school lived in metropolitan city, settling to Jeollabuk-do felt higher satisfaction of returning to village than people who are in their 30s, graduated university, lived in city/district, and now settling to Kyung-book and Choong-nam.

• Journal of the Korean Arthroscopy Society
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• v.12 no.3
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• pp.198-204
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• 2008

Purpose: The purpose of this study is to analyze the merits and demerits of double bundle reconstruction and achieve improvements hereafter, by comparing the results of double bundle and single bundle reconstruction using tibialis anterior allograft. Materials and Methods: Twenty seven patients were divided to undergo either double bundle(n=14) or single bundle(n=13) reconstruction with tibialis anterior allograft tendon. The evaluation methods were AP laxity with KT-2000 arthrometer, isokinetic knee strength measurements, pivot-shift test, IKDC subjective score, Lysholm knee score, Tegner activity score, radiographic evaluations with postoperative MRI, and second look arthroscopy. Results: Lysholm knee score and Tegner activity score were significantly better in double bundle reconstruction. In pivot-shift test, single bundle reconstruction was evaluated as grade 0 in 10 of the knees, grade 1 in 1, and grade 2 in 2. Double bundle reconstruction was evaluated as grade 0 in 13, and grade 2 in 1. In second look arthroscopy, single bundle was evaluated as excellent in 6 of the knees, fair in 7, anteromedial bundle of double bundle reconstruction was excellent in 13 and fair in 1, and posterolateral bundle was excellent in 4, fair in 9, and poor in 1. There were no significant differences in other evaluations. Conclusion: Favorable outcome may be expected with double bundle reconstruction of ACL. However there are still need for improvement in terms of reconstruction technique and rehabilitation protocol to reduce PL bundle injury.

• Journal of Science Education
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• v.42 no.1
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• pp.27-48
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• 2018

The purposes of this study are to derive suggestions and implications to improve the continuity of Korean Science & Practical Arts (Technology Home Economics) curricula through international comparative analysis with focus on the science curricula or standards in five countries (Canada, New Zealand, Singapore, the United States, Korea). Original documents of the national curriculums or standards of each country collected from NCIC comparatively analyzed the big concepts of the 'system' and 'energy' based on features of related components of curriculum contents, vertical, and lateral connectivity. The results indicated that the big concepts of systems and energy were used internationally to consider the curriculum continuity. In most countries, the big concept of system was used as a framework to integrate science with technology or other contents. In particular, it was also utilized to strengthen vertical and lateral connectivity in earth science and space science contents area. In the comparison of countries for the system as the big concept, New Zealand focused interrelationship between system and human activities, systems' interaction, levels and features of system concept for the linkage between grades and subjects on the basis of level. In the case of Canada and Singapore, science and technology are combined to strengthen contents' connection. However, the revised 2015 curriculum has a lack of continuity and sequence because the concepts of system and energy were concentrated on a specific grade and contents' area. The curriculum was not developed systematically for multiple grades according to their levels. In conclusion, Korean science curriculum requires sufficient understanding of students' learning and research on learning progressions and curriculum continuity. In addition, it is very important to constitute the curriculum based on the vertical and lateral connectivity in order to improve science education and to foster students' key competencies and abilities.