• Journal of Intelligence and Information Systems
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• v.23 no.2
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• pp.107-122
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• 2017

Volatility in the stock market returns is a measure of investment risk. It plays a central role in portfolio optimization, asset pricing and risk management as well as most theoretical financial models. Engle(1982) presented a pioneering paper on the stock market volatility that explains the time-variant characteristics embedded in the stock market return volatility. His model, Autoregressive Conditional Heteroscedasticity (ARCH), was generalized by Bollerslev(1986) as GARCH models. Empirical studies have shown that GARCH models describes well the fat-tailed return distributions and volatility clustering phenomenon appearing in stock prices. The parameters of the GARCH models are generally estimated by the maximum likelihood estimation (MLE) based on the standard normal density. But, since 1987 Black Monday, the stock market prices have become very complex and shown a lot of noisy terms. Recent studies start to apply artificial intelligent approach in estimating the GARCH parameters as a substitute for the MLE. The paper presents SVR-based GARCH process and compares with MLE-based GARCH process to estimate the parameters of GARCH models which are known to well forecast stock market volatility. Kernel functions used in SVR estimation process are linear, polynomial and radial. We analyzed the suggested models with KOSPI 200 Index. This index is constituted by 200 blue chip stocks listed in the Korea Exchange. We sampled KOSPI 200 daily closing values from 2010 to 2015. Sample observations are 1487 days. We used 1187 days to train the suggested GARCH models and the remaining 300 days were used as testing data. First, symmetric and asymmetric GARCH models are estimated by MLE. We forecasted KOSPI 200 Index return volatility and the statistical metric MSE shows better results for the asymmetric GARCH models such as E-GARCH or GJR-GARCH. This is consistent with the documented non-normal return distribution characteristics with fat-tail and leptokurtosis. Compared with MLE estimation process, SVR-based GARCH models outperform the MLE methodology in KOSPI 200 Index return volatility forecasting. Polynomial kernel function shows exceptionally lower forecasting accuracy. We suggested Intelligent Volatility Trading System (IVTS) that utilizes the forecasted volatility results. IVTS entry rules are as follows. If forecasted tomorrow volatility will increase then buy volatility today. If forecasted tomorrow volatility will decrease then sell volatility today. If forecasted volatility direction does not change we hold the existing buy or sell positions. IVTS is assumed to buy and sell historical volatility values. This is somewhat unreal because we cannot trade historical volatility values themselves. But our simulation results are meaningful since the Korea Exchange introduced volatility futures contract that traders can trade since November 2014. The trading systems with SVR-based GARCH models show higher returns than MLE-based GARCH in the testing period. And trading profitable percentages of MLE-based GARCH IVTS models range from 47.5% to 50.0%, trading profitable percentages of SVR-based GARCH IVTS models range from 51.8% to 59.7%. MLE-based symmetric S-GARCH shows +150.2% return and SVR-based symmetric S-GARCH shows +526.4% return. MLE-based asymmetric E-GARCH shows -72% return and SVR-based asymmetric E-GARCH shows +245.6% return. MLE-based asymmetric GJR-GARCH shows -98.7% return and SVR-based asymmetric GJR-GARCH shows +126.3% return. Linear kernel function shows higher trading returns than radial kernel function. Best performance of SVR-based IVTS is +526.4% and that of MLE-based IVTS is +150.2%. SVR-based GARCH IVTS shows higher trading frequency. This study has some limitations. Our models are solely based on SVR. Other artificial intelligence models are needed to search for better performance. We do not consider costs incurred in the trading process including brokerage commissions and slippage costs. IVTS trading performance is unreal since we use historical volatility values as trading objects. The exact forecasting of stock market volatility is essential in the real trading as well as asset pricing models. Further studies on other machine learning-based GARCH models can give better information for the stock market investors.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.10
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• pp.2028-2042
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• 1994

Properly defining signal and noise in a self-organizing system like ART(Adaptive Resonance Theory) neural network model raises a number of subtle issues. Pattern context must enter the definition so that input features, treated as irrelevant noise when they are embedded in a given input pattern, may be treated as informative signals when they are embedded in a different input pattern. The ATR automatically self-scales their computational units to embody context and learning dependent definitions of a signal and noise and there is no problem in categorizing input pattern that have features similar in nature. However, when we have imput patterns that have features that are different in size and nature, the use of only one vigilance parameter is not enough to differentiate a signal from noise for a good categorization. For example, if the value fo vigilance parameter is large, then noise may be processed as an informative signal and unnecessary categories are generated: and if the value of vigilance parameter is small, an informative signal may be ignored and treated as noise. Hence it is no easy to achieve a good pattern categorization. To overcome such problems, a Coupled-ART neural network capable of modularized categorization of patterns is proposed. The Coupled-ART has two layer of tightly coupled modules. the upper and the lower. The lower layer processes the global features of a pattern and the structural features, separately in parallel. The upper layer combines the categorized outputs from the lower layer and categorizes the combined output, Hence, due to the modularized categorization of patterns, the Coupled-ART classifies patterns more efficiently than the ART1 model.

• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.2
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• pp.76-84
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• 2013

An adequate downscaling of the official forecasts of Korea Meteorological Administration (KMA) is a prerequisite to improving the value and utility of agrometeorological information in rural areas, where complex terrain and small farms constitute major features of the landscape. In this study, we suggest a simple correction scheme for scaling down the KMA temperature forecasts from mesoscale (5 km by 5 km) to the local scale (30 m by 30 m) across a rural catchment, especially under temperature inversion conditions. The study area is a rural catchment of $50km^2$ area with complex terrain and located on a southern slope of Mountain Jiri National Park. Temperature forecasts for 0600 LST on 62 days with temperature inversion were selected from the fall 2011-spring 2012 KMA data archive. A geospatial correction scheme which can simulate both cold air drainage and the so-called 'thermal belt' was used to derive the site-specific temperature deviation across the study area at a 30 m by 30 m resolution from the original 5 km by 5 km forecast grids. The observed temperature data at 12 validation sites within the study area showed a substantial reduction in forecast error: from ${\pm}2^{\circ}C$ to ${\pm}1^{\circ}C$ in the mean error range and from $1.9^{\circ}C$ to $1.6^{\circ}C$ in the root mean square error. Improvement was most remarkable at low lying locations showing frequent cold pooling events. Temperature prediction error was less than $2^{\circ}C$ for more than 80% of the observed inversion cases and less than $1^{\circ}C$ for half of the cases. Temperature forecasts corrected by this scheme may accelerate implementation of the freeze and frost early warning service for major fruits growing regions in Korea.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.4
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• pp.32-50
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• 2019

The present study examines the circumstances around the establishment of the Seonyu Eight Scenic Spots (仙遊八景) in Gogunsan Islands and the characteristics of the landscape of each viewing point. The study conclusions are as follows. First, since the scenic spots were first established in 1969, their content and sequences have been changed several times, and their names have also been changed to some extent. Until the 1970s, these scenic spots did not have official names for them and were often specified as 'Gogunsan Eight Scenic Spots', and excluded 'the Musan Twelve Peaks (巫山十二峰)'. In addition, viewing points of the eight scenic spots varied across periods. This suggests that, for the early form of Seonyu Eight Scenic Spots, the picturesque scenery of Gogunsan Islands, and Seonyudo Island in particular, was chosen, while eight scenic spots in its vicinity were regarded. Second, the Seonyu Eight Scenic Spots of the early 2000s, which has all eight scenic spots of now, follows the nomenclature of the traditional eight scenic spots by specifying the sequence number with a refined name in four syllables. Its first scenic spot was Mangju Waterfall (望主瀑布) and its eighth scenic spot was Seonyu Sunset (仙遊落照); currently, the first scenic spot is Seonyu Sunset and the second scenic spot is Mangju Waterfall. Such change in the sequence of viewing points resulted from differences in representative landscape resources between the periods. Third, the lack of structure and finesse due to continuous changes is directed related to the identity issue of the Seonyu Eight Scenic Spots. Above all, it is unclear by whom and when Seonyu Eight Scenic Spots was established, and there are clear traces of following the eight scenic spots in the neighboring areas such as Okgu (沃溝) and Impi (臨陂)'s Eight Scenic Spots. Moreover, it is evaluated to have an unrefined, incomplete structure due to the lack of clarity in the knowledge and information about viewing objects, when to view, and historical and cultural background. Fourth, the first scenic spot, Seonyu Sunset, has the image that dominates the entire Eight Scenic Spots. The temporary landscape, the sunset, became the best view because it was perceived as the entirety of the landscape created by the fusion of the beautiful natural elements of Seonyudo Island. Therefore, there is ample room for raising the value of other landscape resources of Gogunsan Islands by utilizing the existing perception of exploring the entire landscape of Seonyudo Island and Gogunsan Islands starting with Seonyu Sunset. This likely requires additional work to imbue each viewing point with identity and completion.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.1
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• pp.9-16
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• 2018

Landscape architecture is an indispensable professional service in building sustainable land and urban environments. The landscape architecture industry is closely related to the promotion of the health and welfare of the people, urban revitalization and residential environment improvement as well as job creation. Despite various public interest values of landscape architecture, the growth engine of the landscape architecture industry, which is supposed to improve the quality of landscape services, has stagnated. In 2015, the Landscape Architecture Promotion Act was enacted to provide a landscape architectural promotion facility and complex system to support revitalization through the integration of the landscape architecture industry. The purpose of this study is to suggest an improvement plan to enhance the effectiveness of the landscape architectural promotion facility and complex system. The results of the analysis are as follows: First, workers and experts in landscape architecture recognized the need for policies and projects to promote the landscape architecture industry. Second, the industrial types suitable for the landscape architectural promotion facility were landscape design, landscape maintenance and management, and landscape construction industry. Meanwhile the industrial types suitable for a landscape architectural promotion complex were landscape trees and landscape facilities production and distribution. Third, the expected effect of the designation of the landscape architectural facility was 'the increase of the business opportunity through the expansion of the network'. On the other hand, that of the landscape architectural promotion complex was 'the activation of various information sharing'. Fourth, 'the size of the local government landscape architecture industry and the capacity to cultivate' was the most important among the designation criteria of the landscape architectural promotion facility. As for that of the landscape architectural promotion complex, the 'feasibility of promotion plan' was the most crucial. Fifth, 'tax benefit and deductible exemption' was considered as a necessary support method for the activation of the landscape architectural promotion facility, and 'maintenance and management fee support' was recognized in the case of the landscape architectural promotion complex.

• Archives of design research
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• v.18 no.4 s.62
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• pp.25-34
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• 2005

The purpose of the present study is to investigate the characteristics of the current Victorian-style interior by reviewing the basic Victorian-style house in the past. this research was analyzed various prior studies and literatures, and found the following results: First, the Victorian-style house and interior space showed various historical trends and adopted every style from Gothic to rococo, and sometimes more than one style influenced a single place. Its formality was applied depending on the function and standard of each room. Second, the interior had many decorative things with free, irregular or other patterns, influenced by Romanticism and Naturalism. The several environmental factors such as air pollution and hygienic matter were also related with its trend. the dramatic changes in the kitchen and sanitary facilities were appeared based on the technical development, and affluent design styles were also used. All these reflected the characteristics of the Victorian age. In conclusion, the characteristics of Victorian-style were influenced by many factors including: (a) the trend of Romanticism and Naturalism, (b) consideration of family convenience based on the technical development, (c) the Socio-Environmental factors like air pollution and the social norm, and (d) reflection of the individual value in accordance with frequent contacts with foreign cultures. In this respect, it is necessary to reevaluate the Victorian-style after paying due regard to such factors.

• Journal of Food Hygiene and Safety
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• v.20 no.1
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• pp.22-35
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• 2005

A survey was conducted to investigate the perception of food sanitation officers toward the Genetically Modified Foods. They were mainly from Regional Agencies of KFDA, City/Province office, and National quarantine station. Some of them were professors of university and researchers of research institute. Most of respondents had experiences of hearing or reading GM foods (over $95\%$) and over $90\%$ of respondents much needed the label of GM foods. Although some of officers of city/province office and national quarantine station showed less knowledge than other respondent groups, most of respondents had basic knowledge about biology. The frequency of respondents worked over 20 years and worked in the general administration was higher than that of other groups in the question of unsafe of GM foods. The answer frequency of careless treatment of foods was highest in the question of risk factor, and the frequency of GM foods was lowest ($4.4\%$). It was concluded that food sanitation officers had positive opinion about GM foods, but there were some differences in the knowledge among agencies. Therefore, it is necessary more educations and informations are needed for food sanitation officers.

• Archives of design research
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• v.17 no.2
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• pp.95-104
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• 2004

Creativity is a important keyword for users as well as for main design organization who needs it. But little attention has been given to the aspect of user's creativity, also there has been a few attempt to apply it into design development until now. Nowadays in design areas, user's experiences and actions are changing the passive states receiving meanings into the active states creating meanings voluntarily. It is resonable to suppose that creative stage is important for users and they have the possibility of new ideas of uses and creating new productions. User's experiences of objects includes that of being formed or supported previously and that of voluntary interpretations acquired for himself, which it may be the possibilities predicted in design process or unknown user's action areas. It is likely that creative use process by themselves are the actions applied and deviated from usability and function by main design organization, also creative productions are arranged and made by users. These have a scope of examination and research in probability that is occurs frequently in user. In this research, approaching with a term, 'User gestures', User gestures are the characteristic action areas based on user's voluntary behaviors, where are revealed a unessential and non-operational function as a action itself and various transformation and creation of products as a outcome of action. This fact proves clearly that user gestures have a worth of alive spectrum to observe aspects of user culture and could be a attractive approach to seek easily new design concept for designer and developer. A further direction of this study will be following areas, Ethnography methods research of user gestures, Cultural research to phenomenon of user design and UGSBD(User gesture scenario based design) research. And it seems probable that they are applied in design development as follows, User initiative customization products, User participatory recycling products and creativity-experience design.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.12
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• pp.1903-1914
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• 2008

The purpose of this study was to propose an efficient and feasible global market entry strategy for the Korean apparel industry by analyzing the Italian fashion industry. In particular, the study investigated the role of foreign exhibitions and showrooms supported and organized by Italian fashion organizations. The methodology for this study was to analyze industrial reports, review previous studies and conduct in-depth interviews with 23 industry experts in Italy, Korea and LA. The results indicated that the most prominent factor in the Italian fashion industry was the fashion cluster, which is a strong and organic network of diverse fashion related areas No matter the size of the enterprise, firms can get practical, prompt and efficient support from diverse associations. The network operated by the associations provides strong support to each firm by organizing collections and exhibitions, and providing promotional activities. Showrooms and agents are another supportive "gate keeper", directly related to an enterprise's sales. However, Korean fashion firms did not have enough information or knowledge for foreign exhibitions, nor did they make aggressive promotional efforts in the global market. Despite the many fashion-related associations exist in Korea, their programs are too focused on visible accomplishments and are too oriented on "big company" and "big voice", rather than many "small firms". In conclusion, the Korean fashion industry-particularly the fashion industry in Seoul-has strong potential to become the center of the global fashion market in the future. However, the fashion support system that can act as the channel to promote firms and to meet global buyers needs to be supplemented. To feasibly create this system, government or industry associations should develop a strong and generous support system and network, and they must recognize the need for small firms to exist.

• Archives of design research
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• v.11 no.2
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• pp.129-140
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• 1998

This study aimed to grqJe for and present guideline roodel when the qJerator of domestic small manufacturing industry try to introch1ce the first industrial design by easier and more effective method. As the method of study, first of aiL examined the necessary of introducing industrial design throogh coosidering about the role and importance of small business. And next, analysed and examined the result of researching by enquete that is for qJerators of cbnestic small business. As a result, preconditioos for effective introducing industrial design were found. And, based 00 the preconditioos that were found through researching by enquete, examined the approachable introducing methods. Finally, set up the effectivable introducing methods of industrial design for doo1estic small manufacturing industry as a graphical model. As a result of study, First, the operator of small business who try to introduce industrial design needs to be well aware of these six cooditions as a prenise of effective awroach.1) coosciousness of role and versus a nation and a people of own industry Cereative 2) managing coosideratim and examinatim of a necessity of introducing industrial design as a cata1yst 3) A certain understanding aIntt essence and value of industrial design 4) Study and examinatim about a case of sucessful introducing industrial design arxl common introducing method of small business.5) Befarehand examinatim of introducing method making use of professional design organization and consultatim wicket 6) Prodent examination about the appointlrent puprpose, method of designer and infonmtion about designer. Second, as the position of small bnsiness that introduce industrial design fur the first time, it is confirmed that the aroroach going with introducing types - preliminary introducing, partitial introducing, regular introducing, whole industry level introducing - considered necessity rate of introducing industrial design and introducing range at the same time. This method is able to approach step by step, but it is confinmed that there is a characteristic in being able to select the method freely, and understanding easily for being coostructed visual form.