• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.487-493
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• 2017

The main purpose of this study is to evaluate the main parameters involved in the asphalt pavement distresses, including IRI (International Rough Index), fatigue, and permanent deformation. The main parameters are the region (Seoul and Busan), traffic level, asphalt binder, maximum aggregate of surface course, thickness of the surface course and base. A total of 64 case studies were carried out under the auspices of the KPRP (Korea Pavement Research Program). From the analysis of the KPRP test results, the key factors for the asphalt pavement distress were determined. Considering the effect of one variable in the basic condition, asphalt binder was the major factor having an effect on the distresses for an AADT (Annual Average Daily Traffic) of 5000 in the Seoul area. Among the remaining factors, the results were found to be in the order of the base layer thickness (A), surface layer thickness (B), and aggregate particle size thickness (D). The same results were obtained for an AADT of 10000. In the case of Busan with an AADT of 5000, the same result was obtained as for Seoul. Among the remaining factors, the results were in the order of the base layer thickness (A), aggregate particle thickness (D), and surface layer thickness (B). Even though there was a slight difference in the effect of the traffic level and region, asphalt binder was the parameter having the greatest effect on the asphalt pavement distress. In the case where the effect of multiple parameters was analyzed, the combination of the asphalt binder and base thickness showed a relatively strong effect.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.595-600
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• 1997

To extend the shelf-life of Kochujang, the effects of anti-browning agents and their optimum concentrations were evaluated using organic acids as synergists. Among the physicochemical analyses, amino nitrogen content exhibited the highest correlation with sensory score. Ascorbic acid and citric acid were selected among the anti-browning agents(ascorbic acid, potassium sorbate, calcium chloride) and organic acids(citric acid, lactic acid, oxalic acid) tested on the basis of the highest amino nitrogen content during storage at 55$^{\circ}C$. The appropriate concentration of ascorbic acid was 0.03% based on amino nitrogen content during storage at 55$^{\circ}C$. Combination of 0.06% citric acid with 0.03% ascorbic acid showed the highest amino nitrogen content during storage at 55$^{\circ}C$. From the results, the 0.03% ascorbic acid and 0.06% citric acid were selected as additives for extending the shelf-life. Control(no additive) and additives(0.03% ascorbic acid and 0.06% citric acid) were tested for physicochemical and sensory analyses during storage at 45$^{\circ}C$ and 55$^{\circ}C$. Amino nitrogen content was also highly correlated with sensory score, The marginal amounts of amino nitrogen for control and additives were 174.9mg% and 173.2mg%, respectively. Degradation rate of amino nitrogen was a first order reaction. Compared to control, the predicted shelf-life for adding additives increased 69% and 56% at 45$^{\circ}C$ and 55$^{\circ}C$, respectively.

• (The)Study of the Eastern Classic
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• no.43
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• pp.125-154
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• 2011

Today's digital culture has been realized through various media, and even now, is changing and growing. If the previous digital culture was actualized through technologies such as the Internet, mobile devices etc., today it includes even things that give new life to contents using various medialike this. The moment this digital technical aspect is grafted into culture, a new genre called 'Cultural Contents' is born. Such cultural contents can be seen as a way for classics to approach people in a digital world that is evolving fast like today. To make classics into a cultural content, its basic narrative structure is important. Classics contain the history at the time, the awareness of people who lived at the time and the detailed rite of passage people experienced. This point can be interpreted as classics not just a cultural heritage of the previous era, but having the functionality that can form a consensus of modern people. This thesis views our classic novels of Mongcha group such as 'Guwunmong' and 'Okrubong' as a potential subject of cultural contents, and the problem of how it can be made into a cultural content. To make a cultural content, storytelling is very important. Therefore, the structure and characteristics of novels of Mongcha group was examined, and a synopsis was made based on this. Furthermore, it examined if there are novels of Mongcha group made into contents, and how each work was vitalized and how much ripple effect it had achieved. If each work did not achieve a second or third ripple effect, it examined what the problem was and tried to offer a solution.

• Geophysics and Geophysical Exploration
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• v.15 no.3
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• pp.144-149
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• 2012

Korea Polar Research Institute (KOPRI) has successfully installed two autonomous very broadband three-component seismic stations at the King George Island (KGI), Antarctica, during the 24th KOPRI Antarctic Summer Expedition (2010 ~ 2011). The seismic observation system is originally designed by the Incorporated Research Institutions for Seismology Program for Array Seismic Studies of the Continental Lithosphere Instrument Center, which is fully compatible with the Polar Earth Observing Network seismic system. The installation is to achieve the following major goals: 1. Monitoring local earthquakes and icequakes in and around the KGI, 2. Validating the robustness of seismic system operation under harsh environment. For further intensive studies, we plan to move and install them adding a couple more stations at ice shelf system, e.g., Larsen Ice Shelf System, Antarctica, in 2013 to figure out ice dynamics and physical interaction between lithosphere and cryosphere. In this article, we evaluate seismic station performance and characteristics by examining ambient noise, and provide operational system information such as frequency response and State-Of-Health information.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.841-846
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• 2011

This study was conducted to obtain the information about injury caused by continuous cropping of peony (Paeonia lactiflora). Soil physico-chemical properties, characteristics of microbial distribution and diversities in the continuous cropped field with peony were analyzed. As the results, pH and organic matter content were higher in the continuous cropping soil than those in the first cropping soil. Bulk density was decreased but porosity was increased in the continuous cropping soil. As the cultivation period was lengthened in years, the populations of bacteria and actinomyces were gradually decreased, whereas fungal population was increased. It was shown that the metabolic diversity patterns of the microbial communities in the continuous cropping soil differed from that of the first cropping soil. These results indicate that deterioration of soil quality such as physico-chemical properties including a soil depth, bulk density, porosity and soil pH is related with a continuous cultivation periods, and also affect a microbial population, especially fungi.

• Cross-Cultural Studies
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• v.52
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• pp.223-251
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• 2018

This paper comparatively considered how Korea and Japan address the concept of 'postwar' in descriptions of their literary history. In Japan, 'postwar' refers to the period after World War II (Asia-Pacific War). This word implies a variety of contexts such as collapse, poverty, confusion, calendar reform, reconstruction and restoration as well as a series of historical events such as war, war defeat, and American occupation; and so it has been treated in Japanese society a significant period. In the history of Korean literature, it is after national liberation that the word 'postwar' appeared; however, it has usually indicated 'the period after the Korean War.' The question is that although the term of postwar refers to periods after different wars, Koreans used the term of postwar also in the same way as Japan, and their concept of postwar overlaps with the concept of prewar or postwar used in Japan, and accordingly, side effects are produced that fail to grasp properly the independent characteristics and significance of the Korean War. In conclusion, the Korean War brought about contrasting effects on the history of Korean and Japanese literature. While the Korean War meant a start after the war in Korean literature, it became a turning point marking the end of postwar in Japanese literature. Such different perceptions on postwar also have major implications in that perceptions represent postwar discourses in today's Korea and Japan.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.561-567
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• 2018

This study was carried out to improve the ride quality of high-speed electric multiple unit. Through dynamic analysis of the HEMU-430X, the range of the equivalent conicity with a critical speed of 300 km/h was between 0.05 and 0.25. The initial adopted wheel profile of HEMU-430X was S1002. The equivalent conicity of S1002 with the mileage of more than 40,000 km was about 0.033 and it was confirmed that XP55 is more suitable for stable operation because XP55 has the equivalent conicity of over 0.061. In order to improve ride quality of high-speed electric multiple unit, the change of installation angle of the yaw damper was suggested from $7.35^{\circ}$ to $0^{\circ}$. From sensitivity analysis and optimization, the air spring lateral and vertical stiffness was suggested to be reduced by 30% and the secondary vertical and lateral damper damping coefficient was increased by 50%. By applying this, it was expected that the car body acceleration could be improved by about 20% on average. The HEMU-430X's yaw damper installation angle was changed to $0^{\circ}$ and the damping coefficient of the lateral damper was increased by 30%. When the test run was carried out at the speed of 300 km/h on the Kyungbu high-speed line, the vehicle lateral acceleration had improved by 34.3%. The effect of additional improvement measures proposed in this paper will be tested in the on track test. The riding quality improvement process used in this study can be used to solve ride quality problems that can occur in commercial operation of high-speed electric multiple unit in the future.

• Journal of the Society of Disaster Information
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• v.15 no.2
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• pp.292-300
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• 2019

Purpose: To reduce the noise and vibration of reinforced concrete slab structures, the damping performance is to be performed experimentally after installing hollow core or filling it with liquid. Method: Using the hollow rate as an experimental variable, the damping ratio and stiffness of each test specimen at impact load are obtained to determine the difference between the damping ratio and stiffness of the numerical analysis. In addition, the damping effects are reviewed by comparing the difference in the damping ratio and stiffness of a test specimen filled with liquid 50% of the study. Results: Since the difference in resistance between a specimen with or without hollow core is 5%, it is judged that there is no structural problem, and the injection of liquid into the hollow core can increase the damping ratio, which can reduce noise or vibration. Conclusion: At less than 20% of hollow rate, there was little damping effect, and at 30%, damping effect was found. However, if liquid is injected into the hollow core of the specimen, damping rate is shown to increase, and the injection of liquid into the hollow part is believed to reduce noise or vibration.

• The Journal of the Korea Contents Association
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• v.21 no.5
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• pp.247-258
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• 2021

The purpose of this study is to investigate whether character education program using Youtube PSAs affect psychological and social maturity of pre-service teachers. For data collections, questionnaires and semi-structured interview are used by 23 sophomores majoring in teacher education. The results are as follows. First, the participants showed highly significant improvement on each of two maturities as well as entire psychological and social maturity. Second, the score of factors of social maturity was lower than that of those of psycho maturity. it could be estimated that college students live in nuclear family and individualization is valued more. Third, while pre-test scores of entire psycho-social maturity are not statistically significant, post-test scores of each of psycho-social maturity indicated statistical significance. In particular, unlike pre-test, there is a strong positive correlation in post-test due to mutually positive impact of two factors. Fourth, there was no statistically significant sex difference. Lastly, according to the result of interview, participants had strong views on the effects of personality education associated with use of Youtube PSAs on motivation and focus in class, caring for others, and leading to positive behaviors.

• Korean Journal of Legislative Studies
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• v.24 no.2
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• pp.39-66
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• 2018

This paper analyzes the structures and issues of 2018 Korean local elections based on the author's observations on the electoral processes. Even if this paper does not follow a traditional statistical method, it provides the interpretative meanings of 2018 local elections by utilizing an expert's observations of campaign processes. This result of 2018 election can be summarized into two analytical frames. In terms of electoral competition structure, three key factors, such as presidential approval rating, party competition structure, ideological spectrum, tend to affect the winning of governing party. In the light of election issue, the inter-Korean summit, the Washington-Pyeongyang summit, Incheon deprecating remark were positive to the vote gains of governing party, but the negative campaign, the drucking scandal and the swing voters were found not to be significant. The local election in Korea tends to show dual meanings, a proxy war of national-level politics and a composition process of local government. This paper found that the 2018 election has dual meanings at the same time, in a sense that it is the punishment of the ex-governing party's wrongdoing and the power change of local government.