• Journal of the Korean Geosynthetics Society
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• v.20 no.2
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• pp.23-33
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• 2021

In Korea, many reservoirs have been built for the purpose of solving the food shortage problem and supplying agricultural water. However, the current 75.6% of the reservoirs are in serious aged as more than 50 years have passed since the year of construction. In the case of such an aging reservoir, the stability due to scour and erosion inside the reservoir is very reduced, and if concentrated rainfall due to recent abnormal weather occurs, the aging reservoir may collapse, leading to a lot of damage to property and human life. Accordingly, each agency that manages aging reservoirs uses Ordinary Portland Cement (OPC) as an injection material and applies the grouting method. However, in the case of OPC, it may deteriorate over time and water leakage may occur again. And there are environmental problems such as consumption of natural resources and generation of greenhouse gases. So, there is a need to develop new materials and methods that can replace the OPC. In this study, an laboratory test and analysis were performed on the grout material developed to induce a curing reaction similar to that of OPC by recycling power plant byproduct. In addition, test in the field such as electric resistivity survey, Standard Penetration Test (SPT), and field permeability test were performed to analyzed to reinforcement effect and determine the possibility of using instead of OPC. As a results of the test, in the case of recycled power plant byproduct, the compressive strength was 2.9 to 3.2 times and the deformation modulus was 2.3 to 3.3 times higher, indicating that it is excellent in strength and can be used instead of OPC. And it was analyzed that the N value of the reservoir was increased by 1~2, and the coefficient of permeability (k) decreased to the level of 8.9~42.5%. showing sufficient reinforcing effect in terms of order.

• Journal of the Society of Disaster Information
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• v.17 no.1
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• pp.10-24
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• 2021

Purpose: The purpose of this study is to determine the dangers of biodiesel and general diesel mixtures currently used as alternative fuels by equipment (tag method and penski Marten method) and to determine the difference between flash point and combustion point (closed, open) according to test methods. It is intended to be used as a reference material for identification and evaluation of firecausing substances by confirming the risk of mixtures by comparative analysis and measurement, and establishing a risk assessment method for chemical substances. Method: Flash point test method and result treatment were tested based on ASTM and KS M mode, which are tag sealing and pen schematense test methods used as flash point and combustion point test methods for crude oil and petroleum products. The manufacturer of the equipment used in this experiment was a test equipment that satisfies the test standards of KS M 2010 with equipment produced by TANAKA of Japan. The flash point and combustion point were measured, and the flash point according to the test method of biodiesel and general diesel mixture ( Closed, open), and the ignition point of a mixture of biodiesel and general diesel was compared and analyzed for ignition risk compared with conventional diesel. Results: Looking at the experimental results, first, as an analysis of the risk of flammability of the mixture, the flash point of a substance containing 70% biodiesel was found to be about 92℃ based on general diesel with a flash point of 64.5℃, and gasoline and biodiesel or When the biodiesel mixture was synthesized, it was confirmed that the flash point tends to decrease. In addition, the difference between the flash point and the combustion point was analyzed as about 20 ~ 30℃, and when a small amount of gasoline or methanol was mixed, the flash point was lowered, but it was confirmed that the combustion point was similar to that of the existing mixture. Conclusion: In this study, in order to secure the effectiveness of the details of the criteria for judging dangerous materials in the existing Dangerous Materials Safety Management Act, and to secure the reliability and reproducibility of the judgment of dangerous materials, we confirm the criteria for judging the risk of the mixture through an experimental study on flammable mixtures. It will be able to provide reference data for experimental criteria for flammable liquids that are regulated in the field. In addition, if this study accumulates know-how on experiment by test method, it is expected that it can be used as a basis for research on risk assessment and research on dangerous goods.

• Journal of the Society of Disaster Information
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• v.16 no.4
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• pp.701-711
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• 2020

Purpose: In this study, the risk of flammability of a liquid mixture was experimentally confirmed because the purpose of this study was to confirm the increase or decrease of the flammability risk in a mixture of two substances (combustible+combustible) and to present the risk of the mixture. Method: Flash point test method and result processing were tested based on KS M 2010-2008, a tag sealing test method used as a flash point test method for crude oil and petroleum products. The manufacturer of the equipment used in this experiment was Japan's TANAKA. The flash point was measured with a test equipment that satisfies the test standards of KS M 2010 with equipment produced by the company, and LP gas was used as the ignition source and water as the cooling water. In addition, when measuring the flash point, the temperature of the cooling water was tested using cooling water of about 2℃. Results: First of all, in the case of flammable + combustible mixtures, there was little change in flash point if the flash point difference between the two substances was not large, and if the flash point difference between the two substances was low, the flash point tended to increase as the number of substances with high flash point increased. However, in the case of toluene and methanol, the flash point of the mixture was lower than that of the material with a lower flash point. Also, in the case of a paint thinner, it was not easy to predict the flash point of the material because it was composed of a mixture, but as a result of experimental measurement, it was measured between -24℃ and 7℃. Conclusion: The results of this study are to determine the risk of mixtures through experimental studies on flammable mixtures for the purpose of securing the effectiveness of the details of the criteria for determining dangerous goods in the existing dangerous goods safety management method and securing the reliability and reproducibility of the determination of dangerous goods Criteria have been presented, and reference data on experimental criteria for flammable liquids that are regulated in firefighting sites can be provided. In addition, if this study accumulates know-how on differences in test methods, it is expected that it can be used as a basis for research on risk assessment of dangerous goods and as a basis for research on dangerous goods determination.

• Journal of Korean Society of Forest Science
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• v.100 no.2
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• pp.202-211
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• 2011

The geometric characteristics of step-pool structures and how they are influenced by channel characteristics were investigated in a steep mountain stream in the Experimental Forests of Kangwon National University in Chuncheon, Gangwon-do. Average values of steps for the study reaches were as follows: step spacing, 4.69 m; step height, 0.47 m; step drop, 0.71 m; step-forming particle sizes, 0.68 m; number, 21steps/ 100 m; the ratio of step spacing to channel width, 0.5; and step steepness, 0.13. Relationships between spacing and height of steps and channel gradient showed a negative- and positive correlation, respectively, whereas all geometric variables of steps manifested poor correlation with channel width. Therefore, step steepness, expressed as the ratio of step height to step spacing, increased as channel gradient increased. The ratio of step steepness to channel gradient representing the criterion of maximum flow resistance was 1.2, indicating the channel bed's stable condition. In particular, the relationship between the ratio of step drop to step height and channel gradient showed a significant negative correlation, suggesting the influence of step-pool geometry in trapping sediment and providing an aquatic habitat. Positive correlations also exist between spacing and drop of steps and step particles. Our findings suggest that the dynamics of step-pool structures may strongly control physical and ecological environments in steep mountain streams, so understanding them is essential for stream management.

• (The) Korean Journal of Educational Psychology
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• v.32 no.3
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• pp.571-596
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• 2018

Objectives: This study investigated the challenges of young cross-cultural individuals (CCIs) through the cultural homelessness (CH) framework. Methods: Through a survey of 151 CCIs, the study empirically examined the relationship between CH and psychological well-being (PWB), as well as the moderating role of emotional clarity (EC). Results: Results indicated that CH was significantly and negatively associated with PWB, especially on the Positive Relations with Others and Environmental Mastery dimensions. Individuals with high CH tended to have less satisfactory relationships and a reduced sense of control over daily life situations, regardless of their EC level. A significant interaction effect between CH and EC was found, specifically in Positive Relations with Others (PR) and Personal Growth (PG). For individuals with high CH, however, satisfactory relationships were dependent on their EC level; they reported more positive relationships with others when their EC levels were high. Interestingly, individuals with high CH were likely to report a high desire for personal growth regardless of their EC level, indicating that they may appear ambitious but may be experiencing unclear emotions. Conclusions: These findings suggest that CH and EC are issues that need to be dealt with simultaneously. As individuals' PWB depends not only on their CH level, but also on their EC, reducing the level of CH should not be the only goal in promoting the well-being of CCIs. Increasing individuals' EC would be just as important, as high EC, along with low CH, predicts important dimensions of PWB.

• (The)Study of the Eastern Classic
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• no.68
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• pp.283-317
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• 2017

Issues over morality and profit usually address relations between moral principles and material gains. In the history of traditional Oriental philosophy, discussions about them were called "Yi-Li zhi bian." The ideas of Confucius and Mencius also contain various discussions about Yi-Li. Both Confucius and Mencius defined Yi as a value concept to represent "natural," "appropriate" or "just" and regarded Yi as an external moral principle on the one hand and an internal moral emotion on the other hand. They had, at the same time, differences, as well. While Confucius placed importance on the external and acquired nature of Yi as a goal of morality, Mencius argued for the internal and innate nature of Yi as the nature of morality partially while recognizing its externality overall. Such Yi is a general term for subjective moral emotions and objective moral principles. Li was a concept of fact to represent "gain," "profit" or "profit-making." Both of them were against private interest and emphasized public interest. As for their differences, Confucius was positive about Li to some degree by saying "One should think of Yi when making profit," whereas Mencius was almost negative about Li and perceived it to be for Yi by saying "One should give up even his own life for Yi." He meant Li's dependence on Yi and also Yi's absoluteness for Ri. Both of them found a mix of opposite features in Yi such as internality and externality, subjectivity and objectivity, specificity and generality, and uniqueness and universality and also in Li such as individuality and specialty and public and private interest. Those features have both disadvantages including theoretical irrationality and logical contradiction and advantages including ideological diversity and conceptual polysemy. If efforts are made to avoid their disadvantages and highlight their advantages, they will provide some elements to consult in the creation of new global ethics required today when East and West are becoming one. In the modern society, the Yi-Li issues can be divided into the issues of morality and economy, personal and social profit, and moral ideal and material gain. If these modern Yi-Li issues are combined with the traditional Yi-Li issues, two paths will emerge over the order of Yi-Li. Of the many perceptions of Yi-Li issues of Confucius and Mencius, the idea of "Yi First, Li Later" can be very useful for creating a new ethics theory to represent "humanism" that we all need today when everyone considers their own pursuit of profit and satisfaction of needs as the best values. Sound Yi-Li relations will be possible only through Yi's orientation toward externality based on internality and Li's pursuit of private interest on the premise of public interest according to the spirit of "Yi First, Li Later."

• (The)Study of the Eastern Classic
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• no.69
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• pp.593-622
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• 2017

The purpose of this study is to investigate the characteristics of Confucianism, Buddhism, and Taoism and to examine the characteristics of Intermixture of Three Religions in Journey to the West. This novel, which has the structure of satire, hope, and surrogate satisfaction while being the center of satire and humor, is a refuge for the people. Even today, it can be said, however, that for the people, Confucianism, Buddhism, and Taoism was not a distinctly separate system of religions. Journey to the West story is about the liberation of Buddhism that is obtained through Taoism training. In the celestial world, not all gods are perfect, and often make mistakes. In such a story, the mistakes of beings living as human beings are simply insignificant. What is not different from the structure of life in this world is still a world of nature. The world is rife with absurdities, both on earth and in heaven. The characteristics of Intermixture of Three Religions can be summarized in several ways. First, the Trip of Samjang is not just to gain the enlightenment of illegal but rather to seek a greater sense of meaning. Second, the means to gain enlightenment is that it does not claim that one is right or good. Third, mercy, goodwill, and respect for life for oppressed and exploited peoples are common to all religions. Fourth, this story suggests that everything from the beginning is already a matter of mind. Fifth, all of the logic of Three Religions in this novel can be said to be "preliminary." Human life implies that it is going on a planned path, perhaps as a fate. But the important thing is, as in all religions, even if the road is a planned one, Journey to the West is strongly and persuasively speaking that it is the way of life as well as the attitude of living silently in carrying out its duties.

• (The)Study of the Eastern Classic
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• no.57
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• pp.231-262
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• 2014

Seeing so many people who use trickery and schemes become successful these days, a lot of people are concerned that the ethical values of our society are breaking down. The saint who created I'Ching presents ways to see through the characteristics of people and ethical values, claims that carrying out these values in everyday life while being aware of misfortunes can lessen our faults or make them disappear, and presents ways to conduct moral actions to people with the hopes of walking down the right road. The Do in Dodeok, which means "ethics" in Korean, stands for "body." Until now, there has been a lack of research on the do in I'Ching. Therefore, the goal of this study was to research the idea and specific actions of Do implied in Gyeomun and Shibik of I'Ching, to aid application of abstract Do to fit the different situations of people. In the beginning, Do was not categorized. It was heavens Do if it was in the heavens, earth Do if it was on the earth, and human Do if it referred to people. I'Ching presents various different ideas of Do to apply natural Do to people. The researcher divided Do largely into heavens Do, earth Do, human Do, heavens, earth and human Do, middle Do and changing Do, and aimed to present various examples of application of Do including Do of a man, Do of heaven and earth, Do of heavens and gods, orders of the heavens, Do of a woman, Do of a family, Do of a saint, Do of a great person, Do of a noble man, Do of a child, Do of a household, Do of the heavens, earth and people, good fortune of men, and wrong Do and frugal Do, to show how and when Do is used and aid in execution of Do through I'Ching. The practice principle of Do according to I'Ching is for people to understand the various types of Do presented by I'Ching, and help all people become saints and noble men by conducting Do at the right time and place. If people make an effort to keep the principle of Do presented in I'Ching, all trickery and schemer will disappear and a society of great unity will be created, where all members are happy.

• (The)Study of the Eastern Classic
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• no.36
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• pp.163-202
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• 2009

The poems of Shin Suk-ju can be divided into two periods around the political change by King Sejo; his poems from the former period show that the poet enjoyed abundant pride and leisurely spirit in the self-satisfying world driven by his determination to maintain a pure heart and save and awaken the people during the reign of King Sejong. His ideology of awakening the people, however, was the product of his heroic consciousness to achieve immortal fame. It was his heroic consciousness and determination to sacrifice his life for fame according to the mandate from Heaven that made him join the political change by King Sejo. His poems from the latter period clearly reveal that the way of his life to pursue fame didn't bring him spiritual satisfaction and happiness. He confessed that his conscience was destroyed as he joined King Sejo in his political change and the deeds he achieved and further his life itself were all in vain. He lost the values or orders he pursued, which caused instability in his life. Facing such instability head-on, he argued that right and wrong, true and false, and good and evil mentioned in the world were all subjective and groundless. Furthermore, he realized all the things and creatures of the world were nothing but phantoms. Those perceptions he had were based on Madhyamaka of Buddhism. Going through such a thinking process, the poet wrote about his mentality of a false reputation with ideal mentality. Heroic consciousness, Buddhist thinking, and pursuit of mentality of a false reputation found in his poems make also frequent appearances in the poems by major literary men in the latter half of the 15th century such as Seo Geo-jeong. His serious searches to overcome his conscientious agony and sense of futility about life had influences on the attitudes toward life and literature of the official literary men of the times. Seong Hyeon's statement that the major literary figures of the times inherited the literary tradition of Shin Suk-ju was not a rhetoric by courtesy.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.9 no.3
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• pp.39-52
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• 1999

In this paper we propose a new watermarking technique for copyright protection of images. The proposed technique is based on a spatial masking method with a spatial scale parameter. In general it becomes more robust against various attacks but with some degradations on the image quality as the amplitude of the watermark increases. On the other hand it becomes perceptually more invisible but more vulnerable to various attacks as the amplitude of the watermark decreases. Thus it is quite complex to decide the compromise between the robustness of watermark and its visibility. We note that watermarking using the spread spectrum is not robust enought. That is there may be some areas in the image that are tolerable to strong watermark signals. However large smooth areas may not be strong enough. Thus in order to enhance the invisibility of watermarked image for those areas the spatial masking characteristics of the HVS(Human Visual System) should be exploited. That is for texture regions the magnitude of the watermark can be large whereas for those smooth regions the magnitude of the watermark can be small. As a result the proposed watermarking algorithm is intend to satisfy both the robustness of watermark and the quality of the image. The experimental results show that the proposed algorithm is robust to image deformations(such as compression adding noise image scaling clipping and collusion attack).