• Korean Journal of Environment and Ecology
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• v.27 no.4
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• pp.417-428
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• 2013

The red fox (Vulpes vulpes), listed as a Class I endangered species by the Ministry of Environment of Korea, has been considered to be extinct in South Korea since the 1980s, and an intensive restoration project has been underway in Sobaeksan national park. This study was carried out to develop a suitable model for the red fox reintroduction program based on Population viability analysis (PVA) by using the VORTEX program. If 10 animals (5 females and 5 males) were continuously released into the initial zero population every year for 10 years, population growth rate and extinction probability over the next 50 years after the introduction of the population were $0.018{\pm}0.204$ and 0.354, respectively; the maximum population size was 116.34 at the 16th year after the first release, and a reduction rate of 1.22 every year from the 17th year was inferred. We found that additional releases would be needed from the 17th year after the initial release to maintain a positive growth rate and to prevent the extinction of the released red foxes, and releasing more than 12 individuals every year would be needed for the long-term, continuous existence of red foxes. By contrast, if fewer than 6 red fox individuals were released the extinction probability over the next 50 years was more than 80%. To maintain the minimum population growth rate, the release of more than 8 individuals were needed for positive population growth. The population growth rate was more stable when 10 animals in the change of their sex rate every year from the set value were released as the female-to- male sex ratio of 6:4 rather than 1:1. However, if the female-biased sex ratio was increased by more than 7:3, a negative population growth was expected. The occurrence rate of roadkill and poaching are important factors in the red fox restoration project. The extinction probability was decreased to 30% if each factor was decreased to 3% based on the standard baseline; however, if each factor was increased to more than 3%, an extinction rate of about 90% was reached over the next 50 years.

• Journal of Korean Home Economics Education Association
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• v.21 no.1
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• pp.89-106
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• 2009

The purpose of this study was to investigate the perspectives on curriculum of secondary school home economics(HE) teachers, the HE teacher efficacy level, and the correlation between their perspectives on HE curriculum and the HE teacher efficacy. A questionnaire survey was carried out to the 500 HE teachers from middle and high schools across the nation, 215 questionnaires were used in the final analysis. The findings of this study were as follows: First, most of HE teachers had the biggest interest in interpretative perspective and some teachers had a interest in critical perspective. On the other hand, a few teachers only had a interest in technical curriculum perspective. Second, HE teachers who worked in the big cities tended to be more interested in interpretative perspective than those who worked in small cities. HE teachers from 25 to 40 years olds tended to be more interested in critical perspective than those who were more than 50 years old. Also, HE teachers with less than 15 years of experience tended to be more interested in critical perspective than those who had worked for more than 15 years. Third, the average of the HE teacher efficacy level was 3.69. The efficacy level of studying support was the highest. Then came class support, environment support, instruction strategy, and demands alternation in order. Fourth, there was moderate correlation between the interpretative perspective on curriculum of middle and high school HE teachers and teacher efficacy level in comparison with other curriculum perspectives.

• (The) Research of the performance art and culture
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• no.37
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• pp.249-293
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• 2018

The Musical Theatre was a popular art genre that originated from the western musical tradition represented by the European opera. In the twentieth century, it bloomed around Broadway in the United States. It is also one of the commercial arts which is popularly loved by the public in the field of performing arts all over the world at present. Due to the nature of this genre, the development of dramas and the expression of characters use music, not words or gestures, as the main medium. And the style of music reacts sensitively to the taste of the public, not to a particular class. When Japan colonized Korea, the empire strongly believed modernization equaled westernization and Japan was the one who could awaken Korean. The Japanese colonial music education was intended to bring cooperation and obedience to Japan by forcibly injecting Japanese ideology and culture into Joseon people. The music education of colonialism with the textbook of the "Songs for public education(보통교육 창가집)" compiled by the Japanese government was a sparkstone for the conversion of the Korean musical identity to Japanese and Western music. In addition to the capitalistic economical mechanism for establishing a South Korean government friendly with the United States during the Cold War after liberation, and the rush of American Pop culture represented by 'the show stage in 8th US Arm' and 'movies' which are to be the influence of invisible 'new cultural imperialism', our traditional music was confined to the meaning of 'Korean music', meaning 'past music'. In Korea, after the liberation, the musical was introduced by the influx of American popular culture. In accordance with the cultural policy of Park Jeong-hee regime, which aimed to spread the 'healthy culture' through the modernization of traditional arts, 'The Yegreen(예그린악단)' was founded. However, the plan to create a contemporary performing art based on Korean national arts showed the possibility of success in 1966 with the success of , but soon after, they have been destined to fall into an institution that has lost their ability to operate on their own due to the suspension of the sponsorship of the regime. Due to the cultural imperialist strategy of the influence of Japanese imperialism's colonial music education and influx of American popular culture after liberation, in the early days of Korean musicals, our traditional aesthetic style brought about the situation of the 1960 's, which did not become an independent ethnic art through the exchange and expansion with Western music. This is the background of the western licensed musicals led by the Korean musical market in the 21st century as well as the main cause of musical creation based on western music.

• Journal of The Korean Astronomical Society
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• v.52 no.1
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• pp.11-21
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• 2019

Intensive Monitoring Survey of Nearby Galaxies (IMSNG) is a high cadence observation program monitoring nearby galaxies with high probabilities of hosting supernovae (SNe). IMSNG aims to constrain the SN explosion mechanism by inferring sizes of SN progenitor systems through the detection of the shock-heated emission that lasts less than a few days after the SN explosion. To catch the signal, IMSNG utilizes a network of 0.5-m to 1-m class telescopes around the world and monitors the images of 60 nearby galaxies at distances D < 50 Mpc to a cadence as short as a few hours. The target galaxies are bright in near-ultraviolet (NUV) with $M_{NUV}$ < -18.4 AB mag and have high probabilities of hosting SNe ($0.06SN\;yr^{-1}$ per galaxy). With this strategy, we expect to detect the early light curves of 3.4 SNe per year to a depth of R ~ 19.5 mag, enabling us to detect the shock-heated emission from a progenitor star with a radius as small as $0.1R_{\odot}$. The accumulated data will be also useful for studying faint features around the target galaxies and other science projects. So far, 18 SNe have occurred in our target fields (16 in IMSNG galaxies) over 5 years, confirming our SN rate estimate of $0.06SN\;yr^{-1}$ per galaxy.

• The Korean Journal of Archival Studies
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• no.14
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• pp.153-190
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• 2006

Externally, business environment in public institution has being changed as government business reference model(BRM) appeared and business management systems for transparency of a policy decision process are introduced. After Records Automation System started its operation, dissatisfaction grows because of inadequacy in system function and the problems about authenticity of electronic records. With these backgrounds, National Archives and Records Service had carried out 'Information Strategy Planning for Reform to Records Management System' for 5 months from September, 2005. As result, this project reengineers current records management processes and presents the world-class system model. After Records and Archives Management Act was made, the records management in public institution has propelled the concept that paper records are handled by means of the electric data management. In this reformed model, however, we concentrates on the electric records, which have gradually replaced the paper records and investigate on the management methodology considering attributes of electric records. According to this new paradigm, the electric records management raises a new issue in the records management territory. As the major contents of the models connecting with electric records management were analyzed and their significance and bounds were closely reviewed, the aim of this paper is the understanding of the future bearings of the management system. Before the analysis of the reformed models, issues in new business environments and their records management were reviewed. The government's BRM and Business management system prepared the general basis that can manage government's whole results on the online and classify them according to its function. In this points, the model is innovative. However considering the records management, problems such as division into Records Classification, definitions and capturing methods of records management objects, limitations of Records Automation System and so on was identified. For solving these problems, the reformed models that has a records classification system based on the business classification, extended electronic records filing system, added functions for strengthening electric records management and so on was proposed. As regards dramatically improving the role of records center in public institution, searching for the basic management methodology of the records management object from various agency and introducing the detail design to keep documents' authenticity, this model forms the basis of the electric records management system. In spite of these innovations, however, the proposed system for real electric records management era is still in its beginning. In near feature, when the studies is concentrated upon the progress of qualified classifications, records capturing plans for foreign records structures such like administration information system, the further study of the previous preservation technology, the developed prospective of electric records management system will be very bright.

• Journal of Climate Change Research
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• v.3 no.4
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• pp.245-257
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• 2012

Vulnerability assessment has been required for establish climate adaptation plan to prevent damage from climate change. In this study we assessed vulnerability with 1 km resolution and determined which sectors have the highest priority in each municipality of Gangwon province based on the result of vulnerability assessment. All sectors of vulnerability assessment are composed of three criteria; sensitivity, exposure and adaptation capacity. And suitable indicators of each sector were selected and spatial data set was prepared using GIS. Priority of vulnerability was classified with the degree of vulnerability in present and variation in vulnerability between present and future. The results of vulnerability assessment were different among municipalities due to the contribution of indicators. Present and future trends in vulnerability showed similar results but high vulnerable area was predicted to expand in the future. In addition increase in temperature led whole area to be more vulnerable generally. The result of prioritizing sectors of vulnerability indicated the most considerable sectors within a municipality. Also, the municipalities which have similar geographic, climatic and social conditions tended to be classified as the same priority class. The method of vulnerability assessment and determining priorities suggested in this study could be used to support decision makers to establish adaptation plan of local area.

• Journal of the Korean Institute of Gas
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• v.26 no.3
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• pp.45-53
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• 2022

In order to improve the emission of diesel engines, natural gas-diesel dual fuel combustion compression ignition engines are in the spotlight. In particular, a reactivity controlled compression ignition (RCCI) combustion strategy is investigated comprehensively due to its possibility to improve both efficiency and emissions. With advanced diesel direct injection timing earlier than TDC, it achieves spontaneous reaction with overall lean mixture from a homogeneous mixture in the entire cylinder area, reducing nitrogen oxides (NOx) and particulate matter (PM) and improving braking heat efficiency at the same time. However, there is a disadvantage in that the amount of incomplete combustion increases in a low load region with a relatively small amount of fuel-air. To solve this, sensitive control according to the diesel injection timing and fuel ratio is required. In this study, experiments were conducted to improve efficiency and exhaust emissions of the natural gas-diesel dual fuel engine at low load, and evaluate combustion stability according to the diesel injection timing at the operation point for power generation. A 6 L-class commercial diesel engine was used for the experiment which was conducted under a 50% load range (~50 kW) at 1,800 rpm. Two injectors with different spray patterns were applied to the experiment, and the fraction of natural gas and diesel injection timing were selected as main parameters. Based on the experimental results, it was confirmed that the brake thermal efficiency increased by up to 1.3%p in the modified injector with the narrow-angle injection added. In addition, the spray pattern of the modified injector was suitable for premixed combustion, increasing operable range in consideration of combustion instability, torque reduction, and emissions level under Tier-V level (0.4 g/kWh for NOx).

• Communications of Mathematical Education
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• v.36 no.3
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• pp.313-334
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• 2022

The purpose of this study is to analyze the changes in mathematical learning through applying STEAM education according to social needs for out-of-school youth. For this purpose, we developed a teaching and learning model and program for mathematics and music STEAM education, and we implemented and analyzed the changes of affective area and problem-solving strategies. The analysis results of characteristic in affective area are as follows: first, the activity-oriented class of mathematics and music STEAM education aroused interest in mathematics. Second, providing opportunities for mathematics and music STEAM education instilled a positive perception of the value of mathematics and STEAM education. Third, the autonomous communication-oriented learning environment of mathematics and music STEAM education improved confidence and motivation to learn in mathematics. The analysis results of the characteristic in problem-solving strategy are as follows: first, through the STEAM education with mathematics and music, a conceptual understanding of internally and externally dividing points was formed, and a given problem was expressed and solved in a formula. Second, the functional correspondence relationship was understood, and the given problem was described and solved with symbols associated with the function. The suggestions of the study are as follows: first, based on the teaching and learning model and results of this study, various STEAM education programs for out-of-school youth should be developed and expanded to foster future competencies and provide new changes for out-of-school youth. Second, it can be used for research on the development of teaching and learning materials for convergence elective subjects in the high school credit system by referring to the mathematics and music convergence STEAM program of this study. As the subjects and fields of STEAM education are diversified and organized, students in need of receiving educational opportunities will be reduced, and there will be a world where the name of out-of-school youth and alternative education will not be necessary. Therefore, it is expected that development of teaching and learning programs created by interest in education of out-of-school youth will be used as an innovative idea in school education to achieve a virtuous cycle.

• Journal of Intelligence and Information Systems
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• v.25 no.2
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• pp.39-55
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• 2019

Recently banks and large financial institutions have introduced lots of Robo-Advisor products. Robo-Advisor is a Robot to produce the optimal asset allocation portfolio for investors by using the financial engineering algorithms without any human intervention. Since the first introduction in Wall Street in 2008, the market size has grown to 60 billion dollars and is expected to expand to 2,000 billion dollars by 2020. Since Robo-Advisor algorithms suggest asset allocation output to investors, mathematical or statistical asset allocation strategies are applied. Mean variance optimization model developed by Markowitz is the typical asset allocation model. The model is a simple but quite intuitive portfolio strategy. For example, assets are allocated in order to minimize the risk on the portfolio while maximizing the expected return on the portfolio using optimization techniques. Despite its theoretical background, both academics and practitioners find that the standard mean variance optimization portfolio is very sensitive to the expected returns calculated by past price data. Corner solutions are often found to be allocated only to a few assets. The Black-Litterman Optimization model overcomes these problems by choosing a neutral Capital Asset Pricing Model equilibrium point. Implied equilibrium returns of each asset are derived from equilibrium market portfolio through reverse optimization. The Black-Litterman model uses a Bayesian approach to combine the subjective views on the price forecast of one or more assets with implied equilibrium returns, resulting a new estimates of risk and expected returns. These new estimates can produce optimal portfolio by the well-known Markowitz mean-variance optimization algorithm. If the investor does not have any views on his asset classes, the Black-Litterman optimization model produce the same portfolio as the market portfolio. What if the subjective views are incorrect? A survey on reports of stocks performance recommended by securities analysts show very poor results. Therefore the incorrect views combined with implied equilibrium returns may produce very poor portfolio output to the Black-Litterman model users. This paper suggests an objective investor views model based on Support Vector Machines(SVM), which have showed good performance results in stock price forecasting. SVM is a discriminative classifier defined by a separating hyper plane. The linear, radial basis and polynomial kernel functions are used to learn the hyper planes. Input variables for the SVM are returns, standard deviations, Stochastics %K and price parity degree for each asset class. SVM output returns expected stock price movements and their probabilities, which are used as input variables in the intelligent views model. The stock price movements are categorized by three phases; down, neutral and up. The expected stock returns make P matrix and their probability results are used in Q matrix. Implied equilibrium returns vector is combined with the intelligent views matrix, resulting the Black-Litterman optimal portfolio. For comparisons, Markowitz mean-variance optimization model and risk parity model are used. The value weighted market portfolio and equal weighted market portfolio are used as benchmark indexes. We collect the 8 KOSPI 200 sector indexes from January 2008 to December 2018 including 132 monthly index values. Training period is from 2008 to 2015 and testing period is from 2016 to 2018. Our suggested intelligent view model combined with implied equilibrium returns produced the optimal Black-Litterman portfolio. The out of sample period portfolio showed better performance compared with the well-known Markowitz mean-variance optimization portfolio, risk parity portfolio and market portfolio. The total return from 3 year-period Black-Litterman portfolio records 6.4%, which is the highest value. The maximum draw down is -20.8%, which is also the lowest value. Sharpe Ratio shows the highest value, 0.17. It measures the return to risk ratio. Overall, our suggested view model shows the possibility of replacing subjective analysts's views with objective view model for practitioners to apply the Robo-Advisor asset allocation algorithms in the real trading fields.