• Journal of Radiation Protection and Research
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• v.47 no.3
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• pp.143-151
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• 2022

Background: After the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, biological alterations in the natural biota, including morphological changes of fir trees in forests surrounding the power plant, have been reported. Focusing on the terminal buds involved in the morphological formation of fir trees, this study developed a method for estimating the absorbed radiation dose rate using radionuclide distribution measurements from tree organs. Materials and Methods: A phantom composed of three-dimensional (3D) tree organs was constructed for the three upper whorls of the fir tree. A terminal bud was evaluated using Monte Carlo simulations for the absorbed dose rate of radionuclides in the tree organs of the whorls. Evaluation of the absorbed dose targeted ¹³¹I, ¹³⁴Cs, and ¹³⁷Cs, the main radionuclides subsequent to the FDNPP accident. The dose contribution from each tree organ was calculated separately using dose coefficients (DC), which express the ratio between the average activity concentration of a radionuclide in each tree organ and the dose rate at the terminal bud. Results and Discussion: The dose estimation indicated that the radionuclides in the terminal bud and bud scale contributed to the absorbed dose rate mainly by beta rays, whereas those in 1-year-old trunk/branches and leaves were contributed by gamma rays. However, the dose contribution from radionuclides in the lower trunk/branches and leaves was negligible. Conclusion: The fir tree model provides organ-specific DC values, which are satisfactory for the practical calculation of the absorbed dose rate of radiation from inside the tree. These calculations are based on the measurement of radionuclide concentrations in tree organs on the 1-year-old leader shoots of fir trees. With the addition of direct gamma ray measurements of the absorbed dose rate from the tree environment, the total absorbed dose rate was estimated in the terminal bud of fir trees in contaminated forests.

• Nuclear Engineering and Technology
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• v.56 no.4
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• pp.1310-1319
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• 2024

The reactor cavity cooling system (RCCS) is a passive reactor safety system commonly present in the designs of High-Temperature Gas-cooled Reactors (HTGR) that removes heat from the reactor pressure vessel by means of natural convection and radiation. It is one of the factors responsible for ensuring that the reactor does not melt down under any plausible accident scenario. For the simulation of accident scenarios, which are transient phenomena unfolding over a span of up to several days, intermediate fidelity methods and system codes must be employed to limit the models' execution time. These models can quantify radiation heat transfer well, but heat transfer caused by natural convection must be quantified with the use of correlations for the heat transfer coefficient. It is difficult to obtain reliable correlations for HTGR RCCS heat transfer coefficients experimentally due to such a system's size. They could, however, be obtained from high-fidelity steady-state simulations of RCCSs. The Rayleigh number in RCCSs is too high for using a Direct Numerical Simulation (DNS) technique; thus, a Reynolds-Averaged Navier-Stokes (RANS) approach must be employed. There are many RANS models, each performing best under different geometry and fluid flow conditions. To find the most suitable one for simulating an RCCS, the RANS models need to be validated. This work benchmarks various RANS models against three experiments performed on the HTTR RCCS Mockup by the Japanese Atomic Energy Agency (JAEA) in 1993. This facility is a 1/6 scale model of a vessel cooling system (VCS) for the High Temperature Engineering Test Reactor (HTTR), which is operated by JAEA. Multiple RANS models were evaluated on a simplified 2d-axisymmetric geometry. They were found to reproduce the experimental temperature profiles with errors of up to 22% for the lowest temperature benchmark and 15% for the higher temperature benchmarks. The results highlight that the pragmatic turbulence models need to be validated for high Rayleigh natural convection-driven flows and improved accordingly, more publicly available experimental data of RCCS resembling experiments is needed and indicate that a 2d-axisymmetric geometry approximation is likely insufficient to capture all the relevant phenomena in RCCS simulations.

• Journal of Ecology and Environment
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• v.44 no.1
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• pp.33-40
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• 2020

Background: Understanding the geographical distribution of a species is a key component of studying its ecology, evolution, and conservation. Although Schlegel's Japanese gecko (Gekko japonicus) is widely distributed in Northeast Asia, its distribution has not been studied in detail. We predicted the present and future distribution of G. japonicus across China, Japan, and Korea based on 19 climatic and 5 environmental variables using the maximum entropy (MaxEnt) species distribution model. Results: Present time major suitable habitats for G. japonicus, having greater than 0.55 probability of presence (threshold based on the average predicted probability of the presence records), are located at coastal and inland cities of China; western, southern, and northern coasts of Kyushu and Honshu in Japan; and southern coastal cities of Korea. Japan contained 69.3% of the suitable habitats, followed by China (27.1%) and Korea (4.2%). Temperature seasonality (66.5% of permutation importance) was the most important predictor of the distribution. Future distributions according to two climate change scenarios predicted that by 2070, and overall suitable habitats would decrease compared to the present habitats by 18.4% (scenario RCP 4.5) and 10.4% (scenario RCP 8.5). In contrast to these overall trends, range expansions are expected in inland areas of China and southern parts of Korea. Conclusions: Suitable habitats predicted for G. japonicus are currently located in coastal cities of Japan, China, and Korea, as well as in isolated patches of inland China. Due to climate change, suitable habitats are expected to shrink along coastlines, particularly at the coastal-edge of climate change zones. Overall, our results provide essential distribution range information for future ecological studies of G. japonicus across its distribution range.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.426-431
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• 2018

This study examines exchange rate volatility spillovers that affect the exchange rate volatility of Korean currency. For this study, the Japanese yen, British pound, Euro, and Canadian dollar are used as the currencies of developed countries, and the Thai baht, Indonesian rupiah, Singapore dollar, and Australian dollar are used as the currencies of the areas near Korea. The GARCH(1.1) model is employed for weekly data covering the period from January 2009 to December 2017. This study finds that the volatility spillovers from the Canadian dollar, Singapore dollar, and Australian dollar to the Korean won are significant, while the volatility spillovers from the Japanese yen, British pound, Euro, Thai baht, and Indonesian rupiah to the Korean won are insignificant. In terms of the economic system and structure, Japan, Britain, and European countries are at a higher level than Korea, while Thailand and Indonesia are at a lower level than Korea. Canada, Singapore, and Australia are almost at the same level as Korea. Therefore, these results appear to be derived from the phenomenon of exchange rate spillovers among countries with a similar economic system and structures, and contradict the literature, which has argued that exchange rates volatility spillovers occur among countries that are in the same area geographically.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.13 no.2
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• pp.59-73
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• 2002

Libraries, not only research libraries but also public libraries, have been fundamentally affected by the immense spread of the Internet and the World Wide Web. Many public libraries have their Web pages, through which they are providing their new and conventional services. There are also web sites which provide library-like services. This paper shows an experimental project named Internet Public Library Asia, which provides information in multiple languages of information resources published in Chinese, Japanese and Korean languages. This paper firstly overviews how traditional public libraries have been affected by the Internet. Then, it describes a few aspects from the viewpoint of crucial library function on the Internet and also from the viewpoint of Asian resources and users. This paper secondly proposes a model to serve information about valuable resources published in multiple Asian languages, and then shows the metadata schema and a few software tools developed for IPL-Asia The name of IPL is borrowed from Internet Public Library based at University of Michigan, since it is, in part, a collaborative activity with the IPL in Michigan. The metadata schema is defined based both on Dublin Core and IEEE LOM and adapted for parallel description in the four languages, i. e. , Chinese, Japanese, Korean and English. The software tools provide functions to support collaboration among people engaged in development of metadata database and metadata editing. These tools have been developed based on the XML technologies.

• Journal of the Korean Society of Costume
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• v.14
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• pp.99-117
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• 1990

The purpose of this study was to investigate the change of clothes in modem Korean women in terms of a socioeconomical background, the introduction to western clothes, and the improvement of clothes between the opening period of ports in the early 1900's and 1960's. In addition, the study investigated how western clothes became popular in a Korean society along with the traditional' Korean clothes, Hanbok. The radical social change since the opening of ports motivated the change in the way of Korean women's thinking, and consequenty the improvement of Hanbok which developed into the clothes-improvement-movement. It was not until 1905 that the improvement of clothes was hotly debated particularly in the matter of abolishing Jangeui and the extreme length of Jeogori and Chima. The Tongchima-Jeogori style which lengthened Jeogori and shortened Chima was widely accepted as everyday wear until the western clothes substituted them after the Independence from Japanese Conquest. As the length of Chima shortened, there occurred a change in Boson and Jipsin as well. There appeared shoes and Gomoosin in place of Jipsin, socks in stead of Boson and were popularized until after the Liberation in 1945. The popularity of Gomoosin diminished markedly with the diversification of shoes styles, due to the improvement of the standard of living with economic development in the 1960's. The traditional Hanbok was gradually differentiated according to the social status, for instance student, teachers, ordinary women, girls and Kisaeng. Especially since the white clothes caused much trouble in washing and sewing, there came into being the movement of wearing colorful clothes. The Movement of abolishing white clothes and promoting of wearing colorful clothes was enforced during the period of Japaness conquest from the 1920's to the Liberation, which consequently stimulated an interest for colors of clothes. The period under the war between 1937 and 1945 was especially noted for the extreme regulation over the clothes. The Japanese government forced each group of women, e.g., girl students, a young women's association, school teachers, and ordinary women and girls, to wear their own uniforms. Also, It recommended the use of Tongchima in stead of long skirts, and buttons in place of Coreum so as to conserve textile encouraging the use of other substitutes to save resources. The western clothes, a model of clothe's improvement was deemed as a symbol of modernization and enjoyed general popularity. The supply of relief clothes after the Korean war accelerated the expansion of western clothes even further and the trend of westernization along with economic progress in the 1960's resulted in wearing of western clothes as everyday dress. The expansion of western clothes as casual wear rapidly diminished wearing of Hanbok which in turn took the position of ceremonial dress worn in special cases only. Hence the Korean women's clothes were dualized into traditional Hanbok and western clothes and the western clothes that stems on its convenience was settled as everyday wear where as the Hanbok appeared as ceremonial dress stressing on ornamental features. As mentioned aboved, we are able to discovered an orientation in the course of transitional process of modern Korean women's clothes admist diversified changes, which is a consistent pursuit of convenience and practicality based upon progmatism. The trend such as this carne into a finale' as women's dress became dualistic in forms of Hanbok and western clothes, and the change since then is supposed to proceed in two forms of dress featuring its own style.

• Journal of the Korean Society for Railway
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• v.18 no.2
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• pp.157-165
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• 2015

At the end of the 19th and in the early 20th centuries, Japan, Korea, and Manchuria, and areas throughout East Asia, suffered a number of cycles of growth and development, for which the railway was a very important development tool and was closely associated with national policy. East Asian affairs, especially at the time, seemed very important to the continent, and their influence on the advance of this remarkable era was especially prominent in Japan. In the midst of this period, the national railway may have evolved under national policy and railway policy and under a variety of organizations and persons of influence. In this paper, we have tried to find the similarities and differences among the three countries that built the East Asia Railway; we consider the characteristics of the East Asia Railway from the perspectives of these three countries. Comparing the characteristics of the three country's railways, first, Japan had the motives of continental expansion and modernization in its pursuit of the railway; in Korea, the railway played the role of a continental rail link; and in Manchuria there was a tendency to pursue direct domination of the railway. Second, the Japanese applied their railway model to Korea; the Korean railway may have been in operation, but it was an extension of the railway of Japan. The railway in Manchuria showed a similar pattern to that which can be found in the state of Asian domination of Europe ; Japan showed aspects of dominance over the railway because it had experience running a private railway.

• The Korean Journal of Financial Management
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• v.8 no.2
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• pp.209-255
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• 1991

This paper develops a simple model to explain the reasons why foreign acquirers pay significantly higher premiums for U.S. target firms than do U.S. buyers. We also provide empirical work on the valuation effect of foreign takeovers and the determinants of the wealth gains of U.S. target shareholders involved in foreign takeovers. The results indicate that target wealth gains are significantly higher in foreign takeovers than in domestic takeovers, after controlling for the wealth effects of payment method, acquisition type, tax status, size and time period of bids. This confirms the valuation effect of foreign takeovers. Furthermore, the results of cross-sectional regression analysis show that the variation in U.S. target wealth gains is explained by extra tax benefits stemming from double tax deductions for acquisition-related interest expenses incurred by foreign acquirers. These findings imply that differential taxation across tax jurisdictions is the main source of the valuation effect of foreign takeovers. In addition, we find that there exists a valuation effect of the nationality of the foreign acquirers. Japanese companies pay significantly higher premiums than do non-Japanese acquirers. The finding also indicates that competition among bidders increases the abnormal returns to U.S. target shareholders in foreign takeovers.

• Journal of the Korean Home Economics Association
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• v.20 no.4
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• pp.155-168
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• 1982

What is attempted here is to find out an optimum method for the design of physical environments that could save human energy expenditures and safely perform household duties. There are, if any, very little amount of research done in this area. This is particulary so when the work relates to the designing of household storage facilities in the light of the energy metabolism of human body. The first step to this study, therefore, is to find out the ways by which we can determine the energy metabolism of human body accurately. To measure the volume and the concentration of human respiration continuously and automatically, a new apparatus is selected here. This includes the recording system with the Wright Respirometer and the Expired Gas Analyzer as well as the computer system to multiply volume by concentration of human respiration and to integrate them for a given time. Then, the author experimented on the reliability of this apparatus and came to the conclusion that this apparatus satisfied our need to research the energy metabolism of human body. Next, the general plan and procedures to experiment with this apparatus have been determined as follows: 1) subjects are three young and sound females. Their physical characteristics are shown in Table 1 and most approximates the standard characteristics of Japanese females, 2) height of open shelves is selected in such away as to correspond to the respective height of each subject(see Table 2), 3) utensils to be stored are box shaped object, which weight is 0.5kg, 1.0kg, 2.0kg or 3.0kg, 4) working motions are given while one or two hands as to place utensil on each shelf from the standard working board, 85 cm in height and then to place back it on the board from the shelf and repeated in constant velocity as 10 times per a minute, 5) each posture of motion is chosen by each subject in free, 6) procedures of measurement of human energy metabolism ard shown at(6), 1, Section 3 as specific methods for using this apparatus. Findings of this study are as follows: 1. Human energy expenditures for storing utensils on shelves by each subject are shown in quantity more accurately than in any other studies, under varying conditions about height of shelves, load of utensils and working motion with one hand and two hands (see Fig. 8~13 and Table 3). 2. Experimental formulae of human energy expenditure for that work are shown as formula (8), (9) and (10), to generalize results of 1. and to apply those for working motion under given conditions. 3. As results of analysis on gained data, we are able to show the standard model of human energy expenditures for storing untensils on shelves by the standard Japanese female (see Table 7 and Fig. 14).

• (The)Study of the Eastern Classic
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• no.68
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• pp.237-281
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• 2017

This research aimed at investigating Kim Gyoshin's recognition on Korean traditional ideology and harmony of Christian idea and traditional idea through the writing and diary in "Bible Joseon". Kim Gyoshin expressed positive interest in Korean traditional idea and traditional religion, and intended to localize Christian belief through communicating with them. He expressed infinite respect for national cultural asset of Buddhism, intending to research Korean Buddhism. He paid utmost attention to Confucianism among traditional ideas. He had a strong affection for learning(好學), benevolence(仁義), conscience(良心) of Confucianism as patriotic character. He calmly practiced caution and solitary(愼獨) of sincere(誠), solemnity(敬) of Confucianism through his life, however he chose Christian belief by accepting atonement belief realizing human sinful nature fundamentally inherent in human being. He personally respected Confucius and lived after the model of him, however he searched the spirit of life to renew the people from Christianity. Academically, he respected Confucius, and believed in Jesus in religion. He highly evaluated the attitude of patriot(志士), which highly regarded the academic attitude of learning(好學) and benevolence(仁義), in this regard, criticized blind and non-intellectual belief. He had an open attitude toward Korean traditional idea with no prejudice. As human individuals have their own inherent moral value, he viewed that each people would have their inherent ethnicity and mission. He considered that Korean Peninsula where contradiction and yoke of the world history are inherent is the center of East Asia that would purify injustice of the world. He viewed that Korean people had owned their original good heart[仁] even before Buddhism and Confucianism had been transmitted to the country. He determined that Korean people were good people, who received goodness from the heaven. However, while Uchimura created Japanese style Christianity by adapting Japanese knighthood to Christian idea, Kim Gyoshin lacked sharp critical mind regarding how to establish Korean style Christianity by adapting which of Korean traditional idea to Christian idea.