• Journal of Korean Society on Water Environment
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• v.36 no.1
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• pp.1-13
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• 2020

The purpose of this study was to investigate the thermal and chemical stratification in Lake Paldang 2013-2018 weekly using Schmidt's stability index (SSI) and the index of chemical stratification (IC-i). The annual average for SSI was 19.1 g cm/㎠ with the maximum value of 45.3 g cm/㎠ in the summer and the minimum value of 4.8 g cm/㎠ in fall-winter showing seasonal differences as well as increased vertical mixing in the summer. The lake stability increased higher in 2016 as compared with the other period. The most influential factors of thermal stratification were temperature and heavy rainfall. Especially, high water temperature and a prolonged residence duration caused by reduced rainfall and inflows could result in an increase of the stratification period. While decreasing inflow and outflow at the end of the rainfall, the thermal stratification was restrengthened within 7-14 days, and then stabilized rapidly before the rainfall. IC-DO increased with high air temperature in the spring and fall-winter. However increasing sunshine duration and residence time and decreasing rate of outflow caused an increase of IC-DO in the summer. Rainfall (less than 800 mm/year) and discharge (less than 200 CMS) significantly declined in 2015 resulting in IC-DO (0.77) increased more than three times over the other years and bottom water hypoxia occurred. The SSI and IC-i used in this study could be applied to other lakes to understand changes in stratification and mixing dynamics.

• Solar Energy
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• v.9 no.2
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• pp.22-30
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• 1989

Since the energy storage method by means of the thermochemical reaction has no heat loss by separating the reactants under the storage period, it is remarked as one of promising means particularly for long-term heat storage. In this study, the heat-storage/-release characteristics of the reversible chemical reaction cycle, $Ca(OH)_2/CaO$, is numerically analysed by a mathematical modelling. As a result, the effectiveness of the heat exchanger by the chemical heat storage method is considerably higher than that by the sensible heat storage method. It is found that the major parameters, which determines the effectiveness of the heat exchanger, are the mass flow rate and inlet temperature of fluid, the residence time, etc.. The heat-storage/-release period can be controlled by changing the operation conditions. It is expected that the results obtained here will supply useful informations in designing a regenerative heat exchanger utilizing the thermochemical reaction.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.332-344
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• 1996

The vertical profiles of the natural $^{210}Po,\;^{210}Pb\;and\;^{234}Th$, activities were measured at the upper 150 m or 200 m of water column from west-east intersection in the east-southern coastal area of the Korea Peninsula during the period from 26 to 29 April 1994 to compare the removal rates (residence time) and removal processes for $^{210}Po\;and\;^{234}Th$. At the inshore stations, the $^{210}Po$ activity was generally higher in the thermocline and its under layer than in the surface mixed layer, while represented the reversed pattern at the offshore stations. However, the $^{210}Pb$ activity decreased generally with depth. Also, the activity of $^{210}Po$ relative to its parent $^{210}Pb$ was deficient in the water column above the main thermocline, but was slightly excess or close to equilibrium in the thermocline and its under layer. The vertical profiles for the activity of $^{210}Pb$ relative to its parent $^{226}Ra$ showed the reversed pattern with the vertical variation of $^{210}Po$ excess (or deficiency). The $^{234}Th$ activity was significantly lower in the surface mixed layer and thermocline than in the deeper layer. The residence time of $^{210}Po$ ranged from 1 to 4 years at the five stations except station E8 that showed yet long residence time (approximately 10 years). The long residence time at the station E8 may resulted from the thicker surface mixed layer and subsequent the vertical mixing of $^{210}Po$ which was recycled in the lower surface mixed layer compared to at the other stations. Also, the residence time of $^{210}Po$ was shorter at the inshore stations than at the offshore stations. However, the residence time of $^{234}Th$ ranged from 52 to 74 days at all station without the significant variation, was very much shorter relative to the residence time of $^{210}Po$. The correlation between the removal rate of dissolved $^{234}Th$ and the concentration of total suspended matter (TSM) was generally positive. Therefore, it seems that the major route of the removal mechanism of $^{234}Th$ from seawater in the surface mixed layer is via adsorption onto suspended particle surfaces (most likely inorganic particles) and subsequent settling to the bottom layer. Between the removal rate of dissolved $^{210}Po$ and the concentration of chlorophyll-a was positively good correlation. Consequently, most likely the removal of $^{210}Po$ may be occurred by uptake to organisms (mainly such as planktonic debris or fecal pellets) and subsequent settling.

• The Korean Journal of Food And Nutrition
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• v.31 no.2
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• pp.293-300
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• 2018

The purpose of this study was to investigate dietary habits, health lifestyle, preference and intake of beverages of Chinese students in Gyeonggi area. Therefore, we try to identify the factors that affect beverage consumption. According to the analysis of the demographic characteristics of male and female Chinese students, there were 155 male students (49.7%) and 157 female students (50.3%). There were statistically significant differences between the residence period and the time of coming to Korea according to sex (p<0.05), but there was no statistically significant difference between the education level, residence type and Korean ability (p>0.05). Analysis of the differences in health-related lifestyle among Chinese students of both sexes showed statistically significant difference in alcohol drinking, smoking, and exercise according to sex (p<0.05), but no statistically significant difference in computer use time (p>0.05). According to the analysis of the dietary habits of the Chinese students, there was a statistically significant difference in the number of meals per day, breakfast, lunch, dinner, snack frequency and number of midnight snacks, but no statistically significant difference in eating out frequency. As a result of the preference test for general beverages, 4.11 points of water, 3.81 points of milk, 3.64 points of fruit and vegetable juice, 3.58 points of tea, 3.25 points of coffee, 3.22 points of carbonated drinks, 2.92 points of functional drinks, respectively. Male students were more likely to prefer water, tea, and health functional drinks while female students had higher preference for fruit, vegetable juice and vinegar drinks (p<0.05). In general, consumption of regular drinks was 4.95 in water, 3.58 in milk, 3.03 in coffee, 2.92 in carbonated drink, 2.91 in fruit and vegetable juice, 2.63 in tea, 2.07 in functional drink, and 1.44 in vinegar appear. Male students had higher intake of water, tea, carbonated drinks, and health functional drinks while female students had higher intake of fruit and vegetable juice (p<0.05). The results of correlation analysis of factors affecting the general drinking of Chinese students are as follows. The intake of tea was related to the period of residence and dietary habits, the intake of milk for breakfast, the number of snacks and midnight snacks for carbonated drinks, and the fruit vegetable juice were related to dietary habits (p<0.01, p<0.05).

• Journal of architectural history
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• v.16 no.6
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• pp.67-86
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• 2007

Choseon Dynasty, from many aspects, saw the institutional establishment of its royal palaces in the 17th and 18th century, with 'donggwol (east palace)' as the most representative form in the era. In that period, palaces were managed in the best way that fits the royal etiquette and order to maintain the Confucian framework of the times. While the royal palace was the place for the king to conduct state affairs, it was also a compound for the royal family to lead a life in. Since the royal family was also based on the Confucian system, women in the royal palace seldom revealed their existence to outside world. Yet daebi,(a Queen Mother) who was often called 'dongjo,' enjoyed the highest level of honor not only as a member of the royal family but in the hierarchical order of the dynasty. As they often engaged themselves in political affairs, daebi raised their reputation through rites and rituals. So, in the 16th century, they largely used Changgyeong-gung palace in the eastern part of the royal compound since they sometimes had to go out of the royal residence. While it was called 'dongjo' because it was seated in the eastern part, it was also used as a word symbolizing daebi. And, therefore, it has become a general principle of royal palaces to build the palace for daebi in the eastern wing of the compound. However, the residence for daebi was not always built in the eastern part in the 17th and 18th century and, instead, edifices for daebi were sometimes erected in several points within the royal compound. Beside, daebi's residence in this period had additional spaces for ceremonies since they had a number of official events there. Construction of daebi's residences in this era was not confined to the symbolic institutions and they became the peculiar palaces with specific characteristics for official ceremonies of the queen mothers. Consequently, it could be said that the architectural style of dongjo, which was the place of the supreme female in the hierarchical order, stemmed from donggwol where daebi spent the longest time of the royal life.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.2
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• pp.19-27
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• 2011

By studying 'Sauidangzi' written by Honggyungmo(1774~1851), this paper shows on the location, the space organization, and the landscape culture of 'Sauidang' which was upper class's house in late period of the Joseon. Sauidang was the residence of about 530 kan(about $1,750m^2$) which was given to Jeongmyunggongju(daughter of Sunzo) by Injo when she married with Hongjuwon, located at the good place where Mt. Mokmyuk, Mt. Dobong, Mt. Inwang, and Janwon peak are harmonized all together. The residence was on the foothill of Mt. Mokmyuk, facing to the northeast. The main house was facing to the east with the inner and back yards, and the separate house(Sauidang) was facing to the west with the garden, and a vegetable field was set in the outer yard where is connected with a main road where willow trees were lined up, 'Sauidang' was called as "the garden of princess", and a stair-shaped flower garden was made to the south, and one could look down the Hanyang castle as a whole. In the garden, there were trees and house plants enriching one's mind to wish an eternal life with oddly shaped stones or flowers, and symbolizing a fairly land. There were 38 types of trees that were planted either on the ground or in pots as various bundles like 1 tree, 2 trees, 3 trees, 4 trees, 5 trees, 8 trees, and 9 trees. Taehosuk, oddly shaped stones, stone panels, stone pillars, jade panels, sundial, walls and fences, stone stairs, steppingstones, and buildings were set for the landscape. Also, the residence had rare luxuries of landscaping culture like Wangheeji's Nanjungsoogyeseo, Sosik's Cheeongjeongi, Jomangboo's Jeokbyukboo, and Anpyungdaegoon's Behaedangcheop.

• Journal of the Korean Geographical Society
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• v.36 no.1
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• pp.35-51
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• 2001

Social historical geography is interested in geographical elements related with a social group and perceives the diverse dimensions of a geographical phenomenon. The purpose of this study is to examine and interpret the multi-layers of meanings associated with the ancestral places of lineage group, i.e. Bonkwans(本貫)in Korea with a viewpoint to social historical geography. The term Bonkwan does not appear in any historical records prior to ths 10th century. Thereafter it is used continuoushy by lineage groups or by govermment agents till the 17th century. I believe that during this long-term period Bonkwan assumed multiple geographical meanings which varied from period to period, such as residence place, a place of origin, and a place symbolizing power. Each layer of meaning was the product of a certain period and of a cetain lineage. Its first meaning was produced in the early Koryo kingdom. Its second meaning from late in the same kingdom to the early part of Chosun kingdom. In order to understand the meaning of Bonkwan correctively, we need to see it at a large perspective. That is to say, it needs to be viewed in the framework of immigration study of each lineage because the term is more is moreof a social construct than a fixed notion.

• Journal of Korea Water Resources Association
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• v.56 no.3
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• pp.173-184
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• 2023

Due to climate change, algal blooms frequently occur not only in Korea but also around the world, and the risk of toxicity of harmful algae has recently been issued. It is known that the representative harmful algae, cyanobacteria, are caused by the intersection of three factors: water temperature, residence time, and nutrients. In this study, water quality simulation was carried out using EFDC, a three-dimensional numerical model, to analyze the variations in water quality due to the decrease of residence time according to the opening of Yeongju Dam in Naeseong-Cheon. In fact, the concentration of chlorophyll-a in Yeongju Dam in the summer of 2021 was significant, exceeding the 'algae warning' for a long time based on the previous algae warning system. On the other hand, as a result of performing the simulation under the condition that the dam gate was completely opened, the concentration of chlorophyll-a was mostly reduced below the 'algae warning' level during the simulation period. It was confirmed that reducing the residence time by restoring the flow of Naeseong-Cheon is a way to immediately reduce algae in Yeongju Dam.

• The Journal of Korean Physical Therapy
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• v.15 no.3
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• pp.91-109
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• 2003

The grip strength is orthopedics department, the place where from rehabilitation medical science and industrial medical science and it evaluates the function of the hand certainly is the ability which is necessary. There is specially by an occupation rehabilitation of mentally retarded child and the evaluation of grip strength is one which is meaning. The samples for this study were 39 normal males and 59 normal females, 62 mentally retarded males, 33 mentally retarded females ranging in age from Prepubeal period to Adolescence. This study was used to measure grip strength BASELINE Hydraulic Hand Dynamometer manufactured by EEI(Fabrication Enterprises Incorporated)in USA. The objective of research from the Prepubeal period to Adolescence the normal and mentally retarded students comparison evaluates the grip strength and effective fine motor program of one's it makes with the fundamental data for a development and it does. The results are as follow : (1) The hand which the normal student and the schoolgirl of rises from grip strength measurement result of the Prepubeal period research object people 10.7Kg with the same left hand was each measured 10Kg with 9.8Kg with in. The grip strength of the mentally retarded schoolboys was the hand which rises 6Kg with the left hand 5.4Kg, the grip strength of the schoolgirls 6.5Kg with was identical. (2) The hand which the normal schoolboys and the schoolgirls rises from grip strength measurement result of the Adolescence research object people 29.6Kg, 20Kg the left hand to be was each measured 27.8Kg with 18.4Kg with. The hand which the mentally retarded schoolboys and the schoolgirls rises 13.1Kg, 11.3Kg the left hand to be was each measured 12.3Kg with 10.9Kg with. (3) Among the normal students $10.2\%$ (Prepubeal period $0.94\%$, Adolescence $15.2\%$) in Mentally Retarded students $17.9\%$ (Prepubeal period $0.77\%$, Adolescence $19.1\%$) left hand it was higher. (4) The grip strength of the students who attend school from the general family dwells were appeared higher than students residence at institution.

• Journal of architectural history
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• v.3 no.2 s.6
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• pp.91-110
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• 1994

This paper is one of Korean towns in the period of Korean-Modern, which play an important role in shaping the present cities of Korea. In the concrete, this study deals with the urban form of the Japanese Concession at Womsan where is the second Open Port in Korea. By the way, both of the Open Port and the Concession were the town that not exist before the period of Korean-Modern, and the town that symbolize the historical characters of the period of Korean-Modern. On this study, it is intended to analyze the situations of establishment, the process of the urban form, and the meanings of Concession, from 1880 to 1910, the period when had been kept up the nature of the Concession mainly. The Japanese Concession at Wonsan was urged it's establishment by Japan Government that is conscious of the purpose of foreign trade and military importance. But, it was slow in progress of developing town because of the distance from the capital 'Han Yang', today we called it Seoul, and lack of the background towns. However, after both the wars of 1895 and 1904, Japanese residents were incresed and urban aspects were advanced. The urban form of Japanese Concession was devided two territories by the natural circumstances, so that was made a difference on the period of the development. And finally, it had double axis on the form of district. Furthermore, by increasing of residence, it was occured that new Japanese resident arwa was occupied and expanded illegally between the road which is toward the existing Korean village 'Womsan-Jin(元山津)'. This indeed is the illegal extension of the Japanese Concession at Wonsan. Conclusively, Concession fumed out the primary factor that Korean towns are altered with the heterogeneous ones in the period of Korean-Modern.