• Korean Journal of Soil Science and Fertilizer
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• v.16 no.2
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• pp.92-97
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• 1983

This experiment was designed to establish the soil physical improvement practice to increase the rice yields at fine textured fluvio-marine paddy field. After chiseling and trenching the paddy soil, the rice growth and soil physical properties were investigated for 4 years. The results are summarize as follows; 1. The soil physical properties, such as bulk density, hardness, porosity and permeability were prominently improved by trenching and chiseling. 2. There were significant relationships among the soil physical properties, root developments and rice yields. 3. The increasing rates of rice yields by soil physical improvement were about 10%, which is better than 5% of drainage effects. 4. The effects of trenching and chiseling on rice yields were continued to fourth year. Even if trenching effects was better than chiseling the chiseling was considered as a useful treatment for its simple working practice by using a heavy machine. 5. In case of trenching, straw application were increased the rice yields.

• Economic and Environmental Geology
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• v.34 no.4
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• pp.385-394
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• 2001

There are serious damage of people and properties every year due to landslides that are occurred by heavy rain. Because these phenomena repeat and the heavy rain is not an atmospheric anomaly, the counter plan becomes necessary. The study area, Ulsan, is one of the seven metropolitan, and largest cities of Korea and has many large facilities such as petrochemical complex and factories of automobile and shipbuilding. So it is necessary assess the landslide hazard potential. In the study. the three steps of landslide hazard assessment techniques such as susceptibility, possibility, and risk were performed to the study area using GIS. For the analyses, the topographic, geologic, soil, forest, meteorological, and population and facility spatial database were constructed. Landslide susceptibility representing how susceptible to a given area was assessed by overlay of the slope, aspect, curvature of topography from the topographic DB, type, material, drainage and effective thickness of soil from the soil DB, lype age, diameter and density from forest DB and land use. Then landslide possibility representing how possible to landslide was assessed by overlay of the susceptibility and rainfall frequency map, Finally, landslide risk representing how dangerous to people and facility was assessed by overlay of the possibil. ity and the population and facility density maps The assessment results can be used to urban and land use plan for landslide hazard prevention.

• Journal of Korean Society for Geospatial Information Science
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• v.25 no.1
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• pp.19-27
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• 2017

This research was aimed to analyze landslide susceptibility and compare the prediction accuracy using ensemble frequency ratio (FR) and logistic regression at the Inje area, Korea. The landslide locations were identified with the before and after aerial photographs of landslide occurrence that were randomly selected for training (70%) and validation (30%). The total twelve landslide-related factors were elevation, slope, aspect, distance to drainage, topographic wetness index, stream power index, soil texture, soil sickness, timber age, timber diameter, timber density, and timber type. The spatial relationship between landslide occurrence and landslide-related factors was analyzed using FR and ensemble model. The produced LSI maps were validated and compared using relative operating characteristics (ROC) curve. The prediction accuracy of produced ensemble LSI map was about 2% higher than FR LSI map. The LSI map produced in this research could be used to establish land use planning and mitigate the damages caused by disaster.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3704-3712
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• 2012

Recently, antiwashout underwater concrete has been increasingly used for marine foundations of long span bridges. However, to shorten the construction period of antiwashout underwater concrete used in marine foundations, high fluidity antiwashout underwater concrete should be manufactured largely improving fluidity than the previous one. Thus, the objective of this experimental research is to suggest optimum mix proportions of high fluidity antiwashout underwater concrete. For this purpose, concrete specimens containing ground granulated blast furnace slag were manufactured according to the dosage of antiwashout admixture for unit binder contents of 550 and 600kg/$m^3$, respectively. And then, their quality performances such as slump flow, setting time, underwater segregation resistance, and ratio of compressive strength were evaluated according to the related specification of Korea Concrete Institute. It was observed from the test results that the minimum dosage of antiwashout admixture was necessary to satisfy the related specification.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.4
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• pp.179-190
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• 2019

To alleviate financing difficulties of small and medium sized enterprises (SMEs), the government and municipal governments are providing a variety of SME policy funding programs. This study introduced the policy funding program of Gangwon-do and quantitatively analyzed the financial performance of companies supported by the Gangwon-do SME policy fund in the year 2014. Specifically, we compared the financial ratios for three years, from 2013 to 2015, between funded firms and non-funded firms. In addition, we applied a regression analysis to see if the policy funding program contributed to profitability (the operating profit growth and return on equity), stability (the interest coverage ratio and debt-to-equity ratio), and growth (the asset growth and sales growth) of the funded firms. The empirical results show that the firms that received the policy funds did not show any improvement compared to non-funded firms in terms of profitability, stability, and growth. This suggests that Gangwon-do should improve the policy funding program, that currently provides only an interest amount of 2-4% of the corporate loan principal, without any strategic selection criteria for the target funded firms, and without any follow-up management system, after support.

• The Journal of the Korea Contents Association
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• v.21 no.2
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• pp.15-34
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• 2021

This study was conducted to review strategic and effective utilization plans and suggest desirable development plans, taking into account the cultural and social values and ideologies of the local government's OSMU strategy and regional economic goals. To this end, the concept and characteristics of OSMU, domestic and international success cases were reviewed, and analyzed the detailed strategies, development results and achievements of Hong Gil-dong theme park in Jangseong-gun, and Simcheong theme park in Gokseong-gun. As a result of these analyses, first, it was confirmed that the Hong Gil-dong theme park and the Simcheong theme park were rational and justifiable choices that emphasized locality and publicity, the core of the local government's OSMU strategy. Second, it was confirmed that while Hong Gil-dong theme park achieved more stable and successful results, Simcheong theme park had poor achievement without utilizing the excellence and valuable goals of the original contents. Therefore, in order to achieve sustainable development while harmoniously satisfying the publicity and profitability, ideology and effectiveness, justification and economics of OSMU strategies of local governments, various research, reflection and work must be continuously carried out.

• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.89-94
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• 2023

Recently, credit risk in the Chinese corporate bond market has increased significantly, and there is a possibility that banks that have invested in corporate bonds may become insolvent. The purpose of this study is to empirically analyze the effect of Chinese commercial banks' investment in securities on financial performance. The analysis results are as follows. First, it is estimated that as the share of securities investment by Chinese commercial banks increases, the bank's profitability decreases. It was found that investment in securities did not have a positive impact on profitability due to the increase in credit risk in the corporate bond market and the increase in marginal companies. Second, it is estimated that as the proportion of securities investment by Chinese commercial banks increases, the bank's soundness deteriorates. As credit risk in China's capital market is increasing, continuous management of non-performing assets is required. Chinese commercial banks need portfolio management through securities investment in addition to loan assets to improve profitability. However, volatility should be managed by adjusting the scale of securities management to an appropriate level.

• 지역과문화
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• v.4 no.1
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• pp.1-26
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• 2017

The 21st century recognizes culture as a high value-added strategic industry as it is called the culture era, and the cultural industry plays a role in driving regional economic development by raising the value added of other industries due to various ripple effects. As the institutional apparatus for developing such cultural industry, the Culture Industry Promotion Basic Law was enacted. Based on this, the Central Government designated the Jung-gu Dong and Seo-gu Dong as the Cultural Industry Promotion District of Andong City in 2010 but it has not been activated until 2017. The purpose of this study is understanding the situation and problems of the Cultural Industry Promotion District of Andong city and to discuss the direction of development. The research methods were analyzed by using questionnaires using AHP analysis technique for experts and practitioners related to culture industry. SPSS 23 was used for the validity and reliability of the questionnaire, and VBA was used for weighting and consistency index calculation in AHP analysis. As a result in the upper layer, Economy efficiency was found to be the most important factor of the three upper layer factors (Economy, Publicity, and Sociality) in order to activate the Cultural Industry Promotion District of Andong city. In the case of the Lieutenant layer, it is analyzed that the Job Creation is an important factor in the Economy category, the Settlement and Environment for Cultural Industry in the Publicity category, and the Activation of Urban Culture Activity in the Sociality category. As a result of analyzing the direction of promotion of the Cultural Industry Promotion District of Andong City centered on these factors, it concluded that the industry related to performance should be focused.

• Journal of Internet of Things and Convergence
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• v.9 no.6
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• pp.57-62
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• 2023

This research is a comparative analysis of the U.S. S&P 500 index using the volatility breakout strategy against the Buy and Hold approach. The volatility breakout strategy is a trading method that exploits price movements after periods of relative market stability or concentration. Specifically, it is observed that large price movements tend to occur more frequently after periods of low volatility. When a stock moves within a narrow price range for a while and then suddenly rises or falls, it is expected to continue moving in that direction. To capitalize on these movements, traders adopt the volatility breakout strategy. The 'k' value is used as a multiplier applied to a measure of recent market volatility. One method of measuring volatility is the Average True Range (ATR), which represents the difference between the highest and lowest prices of recent trading days. The 'k' value plays a crucial role for traders in setting their trade threshold. This study calculated the 'k' value at a general level and compared its returns with the Buy and Hold strategy, finding that algorithmic trading using the volatility breakout strategy achieved slightly higher returns. In the future, we plan to present simulation results for maximizing returns by determining the optimal 'k' value for automated trading of the S&P 500 index using artificial intelligence deep learning techniques.

• Journal of the Korea Concrete Institute
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• v.18 no.1 s.91
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• pp.57-64
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• 2006

The crack presented in concrete structures causes a structural defect, the durability decrease, and external damages etc. Therefore, it is necessary to improve durability through the effort to control the crack. Fluosilicic acid($H_2SiF_6$) is recovered as aqueous solution which absorbs $SiF_4$ produced from the manufacturing of industrial-graded $H_3PO_4$ or HF. Generally, fluosilicates prepared by the reaction between $H_2SiF_6$ and metal salts. Addition of fluosilicates to cement endows odd properties through unique chemical reaction with the fresh and hardened cement. Mix proportions for experiment were modulated at 0.45 of water to cement ratio and $0.0{\sim}2.0%$ of adding ratio of fluosilicate salt based inorganic compound. To evaluate correlation of concrete strength and adding ratio of fluosilicate salt based inorganic compound, the tests were performed about design strength(21, 24, 27 MPa) with 0.5% of adding ratio of fluosilicate salt based inorganic compound. Applications of fluosilicate salt based inorganic compound to reduce cracks resulted from plastic and drying shrinkage, to improve durability are presented in this paper. Durability was evaluated as neutralization, chloride ion penetration depth, freezing thawing resistant tests and weight loss according reinforcement corrosion. It is ascertained that the concrete added fluosilicate salt based inorganic compound showed m ability to reduce the total area and maximum crack width significantly as compared non-added concrete. In addition, the durability of concrete improved because of resistance to crack and watertightness by packing role of fluosilicate salt based inorganic compound obtained and pozzolanic reaction of soluble $SiO_2$ than non-added concrete.