• Korean Chemical Engineering Research
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• v.50 no.3
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• pp.492-498
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• 2012

In this study, hydrodynamics such as solid circulation rate and voidage in the desulfurizer and the reaction characteristics of Zn-based solid sorbents were investigated using lab-scale high pressure and high temperature desulfurization process. The continuous HGD (Hot Gas Desulfurization) process consist of a fast fluidized bed type desulfurizer (6.2 m tall pipe of 0.015 m i.d), a bubbling fluidized bed type regenerator (1.6 m tall bed of 0.053 m i.d), a loop-seal and the pressure control valves. The solid circulation rate was measured by varying the slide-gate opening positions, the gas velocities and temperatures of the desulfurizer and the voidage in the desulfurizer was derived by the same way. At the same gas velocities and the same opening positions of the slide gate, the solid circulation rate, which was similar at the temperature of $300^{\circ}C$ and $550^{\circ}C$, was low at those temperatures compared with a room temperature. The voidage in the desulfurizer showed a fast fluidized bed type when the opening positions of the slide gate were 10~20% while that showed a turbulent fluidized bed type when those of slide gate were 30~40%. The reaction characteristics of Zn-based solid sorbent were investigated by different desulfurization temperatures at 20 atm in the continuous operation. The $H_2S$ removal efficiency tended to decrease below the desulfurization temperature of $450^{\circ}C$. Thus, the 10 hour continuous operation has been performed at the desulfurization temperature of $500^{\circ}C$ in order to maintain the high $H_2S$ removal efficiency. During 10 hour continuous operation, the $H_2S$ removal efficiency was above 99.99% because the $H_2S$ concentration after desulfurization was not detected at the inlet $H_2S$ concentration of 5,000 ppmv condition using UV analyzers (Radas2) and the detector tube (GASTEC) which lower detection limit is 1 ppmv.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.2
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• pp.121-129
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• 2014

Marine algal flora and community structure were seasonally investigated at four sites in the vicinity of the Igidae on the southern east coast of Korea from May 2010 to February 2011. A total of 66 species including 9 of Chlorophyta, 14 of Phaeophyta, 43 of Rhodophyta were found during the survey period. Among these species, 16 species were found throughout the year. Seasonal mean biomass in wet weight was 123.6 (spring), 2,061.6 (summer), 412.0 (autumn), 678.9 (winter) $g{\cdot}m^{-2}$. Maximum biomass was recorded in summer($2,061.6g{\cdot}m^{-2}$), and minimum was recorded in spring($123.6g{\cdot}m^{-2}$). Spatial maximum and minimum species number were recorded at station 3 and 4(50 species) and at station 1(47 species). At station 1, 2 directly exposure on Yongho and Daeyeon cheon (stream) run off, and discharge from Nambu sewage treatment plants near coastal area, species diversity was relatively low and dominant species were similar throughout four seasons. The R/P, C/P and (R+C)/P value reflecting flora characteristics were 3.07, 0.64 and 3.71, respectively. The flora investigated could be classified into six functional groups such as coarsely branch form 39.39 %, sheet form 30.30 %, thick leather form 13.64 %, filamentous form 12.12 %, crustose form 3.03% and jointed calcareous form 1.52 % during survey period. The number of marine algae species in Igidea were 96 species at 1996 to 1997 and 66 species at 2010 to 2011, respectively. The change of seaweed species is due to the pollution loaded from sewage treatment plant and stream. We thus recommend that the positive maintenance control method like sewage treatment, for the protection of seaweed bed should be proceeded to near coastal area.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.5
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• pp.439-458
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• 2013

Temporal and spatial variations of water quality were investigated in the Cheonsu Bay of Yellow Sea, Korea from 2010 to 2011. Water samples were collected at 16 stations and physicochemical parameters were analyzed including water temperature, salinity, suspended solids (SS), chemical oxygen demand (COD), dissolved oxygen (DO), Chlorophyll a and nutrients. Spatial distribution patterns of all survey items were not clear among stations but the bimonthly variations were distinct except the bottom water of the suspended solids. The trend analysis by principal component analysis (PCA) during 2 years revealed the significant variations in water quality in the study area. Spatial water qualities were discriminated into 3 clusters by PCA; station cluster in the surface water 1, 2~11, and 12~16, the bottom water 1, 2~7, and 8~16. Annual bimonthly water qualities were clearly discriminated into 3 clusters by PCA. But tend of cluster in the surface and bottom water was difference, period most of the research was low in nutrient. Ecology-based water quality criteria was a good level of grade II. Bimonthly results are shown as III grade(normal) at June and August, II grade(good) at October and December and I grade for February and April. Water quality was showed by the input of fresh water same as those of Kyoungin coastal area, Asan coastal area, Gunsan coastal and Mokpo coastal area in the Cheonsu.

• Korea journal of population studies
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• v.10 no.1
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• pp.28-38
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• 1987

This paper was set out to study the structure of the career occupational mobility in the early and rapid phase of industrialization in Korea. By analyzing the individual life histories regarding occupational mobility and achievement, I propose a model of yearly career mobility of Korean men and Women during the period of 30 years between 1954 and 1983. With the occupational classification scheme of 5 groups - Upper Nonmanual, Lower Nonmanual, Self Employed, Manual, Farm - the mobility pattern in the person-year mobility table analyzed can be characterized primarily by the strong influence of immobility. The degree of immobility, however, is different by the occupational groups. The absolute amount of immobility can be summarized as being U-shaped. Overall, the pattern of mobility can be explained best by the concept of occupational distance. I then propose a model of relative career occupational mobility pattern that combines the conceptual and theoretical basis and the methodological rigor. The model is based on the notion of the reproduction of inequality, the labor market context, and the life history perspective. The model encompasses the 6 conceptual explanatory factors such as persistence effect, ceiling effect, traditional sector effect, nonmanual occupation effect, alternative mobility channel effect, and occupational distance effect, as well as the effects of both origin and destination occupations. The relative pattern of career mobiliity in Korea can be characterized by the following six findings. First, the persistence effect on the diagonal cells of the mobility table is dominant. Second, a clear evidence of the negative effect of occupational distance between nonmanual occupations and manual and farm occupations is found. Third, the out-mobility from farming took place regardless of the destination occupations. Fourth, the internal mobility within the nonmanual occupation block is high and bi-directional, and is exclusive against other occupations. Fifth, the 'self employed' occupation is serving a peculiar function in both inflow and outflow pattern. Last, the relative pattern of career occupation mobility is asymmetrical in terms of the upward and downward mobility.

• The Korean Society of Law and Medicine
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• v.16 no.2
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• pp.263-291
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• 2015

In May, 2015, a 68 years old man, who has been Middle East Saudi Arabia and the United Arab Emirates, had high fever, muscle aches, cough and shortness of breath. he went two local hospital near his house and the S Medical Center emergency center. He was diagnosed MERS(Middle East respiratory syndrome) and the diseases had put South Korea the fear of epidemics for three months. Especially, this disease has firstly reported in Middle East Asia in September 2012 and spreaded to twenty-six countries. In 21, July, 2015, European Center for disease prevention and control reported 533 people were died and in South Korea, 186 people were infected, 36 people were died and 16,693 people were isolated from MERS. South Korea government were faced into epidemic control and blamed from public. Especially, hospital acquired infection, disease control chain, opening of information, ventilation, lack of isolation bed, the problem of function of local health center, the issue of reparation for hospital and insurance cover rate, the classification of disease, the role of Korea Centers for disease control and prevention, the culture of visiting hospital to see sick people, the issue of hospital multiple room and other related social support policy. it is time to study and discuss to solve these problems. South Korea citizens felt fear and fright from MERS. What is wore, they thought the dieses were out of their government control. It was unusual case for word except Middle East Asia. numerous tourists canceled visiting korea. South korea economic were severly damaged especially, tourism industry. South korea government should admit that they had failed initial action against MERS and take full reasonability from any damages. The government have to open information to public in terms of epidemic diseases and try to prevent any other epidemic diseases and try to work with local governments.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.22 no.3
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• pp.88-102
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• 2017

Long-term changes in bathymetry and grain size of surface sediments were investigated for understanding depositional sedimentary environments in the channelized Yeongsan River Estuary, Korea. The results revealed that an average depth of the estuary had decreased up to 2.1 m from 1982 to 2006, while it had increased to 0.3 m from 2006 to 2012. The rapid decrease of the water depth from 1982 to 2006 was due to the vast deposition of mud caused by the change of water course and flow velocity after the estuary was dammed. Meanwhile the increase of the water depth from 2006 to 2012 may be associated with multiple erosional processes, including a dredging at the southern part of the estuary and other erosions from the dike sluice expansion work. Considering the water-depth change and tidal-level variation in the study area, an depositional rate in the estuary is estimated to be 8~9 cm/yr for the last 2 decades (1982~2006). The sediments of Yeongsan River Estuary are largely composed of silt-clay mixtures: overall, silt is distributed mainly in the shallow area of the estuary edge, while clay is confined to the deep area of the estuary center. Mean grain size of the sediments is 6.0 Ø on average in 1997, 7.8 Ø on average in 2005 and 7.7 Ø on average in 2012, respectively, suggesting that the sediments became finer due to the increase of silt and clay contents in 1997~2005. Furthermore, several lines of evidences, including the comparison between the amounts of the sediment influx discharged from the Yeongsan River and the sediments in the estuary, and the changes in distribution pattern of silt and clay contents implying that they moved from offshore to estuary dike, indicate that the mud sediments are originated mainly from the offshore, not from the river.

• Journal of Ginseng Culture
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• v.1
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• pp.78-92
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• 2019

Among the Southeast Asian countries, Vietnam had the most cultural exchange with Korea. Through Confusion and Chinese character, which were the common measure for two countries, Korea and Vietnam could communicate and share a sentiment with each other. Two countries showed an enormous interest in each other, and hence they could keep good relationship without official diplomatic relations. During the early 19th century, Korean Ginseng had gained tremendous popularity in Vietnam. Vietnamese believed the stamina of Minh Mang, who had 142 sons and daughters, originated from ginseng. Minh Mang bestowed ginseng on old courtiers for their contribution, which made them more loyal to the king. This tradition was inherited to the future generations, and soldiers who fought with Thai, Cambodia and France also received ginseng for their contribution. In other words, ginseng was the very important key for enforcement of patriotism. Due to the tradition, Korean ginseng has been considered as the premium ginseng in Vietnam. It is presumed that ginseng flew into Vietnam through 4 routes; 1) as an imperial gift from Chinese emperor, 2) by the Vietnamese ambassadors who went to Beijing for a tribute, 3) through private trade and 4) from Ryukyu or Japan, which were the hub of international trade. From 15th to 18th century, ambassadors from Chosun and Vietnam actively interacted in Beijing. Through their interchange, Vietnamese royal family could learn about the value of ginseng. The fact that there were many Shilhak scholars among the ambassadors from Joseon, such as Seo Geojeong and Seo Hosu who had profound knowledge of ginseng proves the theory. It is also possible that reputation of ginseng was already established in Vietnam during Silla period. Ko Byung, an bureaucrat from Tang Dynasty who ruled Vietnam for 10 years in middle 9th century and a friend of Choi Chiwon, might have delivered the knowledge of ginseng to the upper class in Vietnam. This hypothesis, however, should be proven by literatures. Hence, further research about the trace of Korean ginseng in Vietnamese history and literary works still remains to be done.

• The Southeast Asian review
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• v.28 no.3
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• pp.159-212
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• 2018

This paper is focused on analyzing the social environment of a rapidly changing on Vietnamese company. The key analysis of this study is on the change of perception in Vietnam and the regional difference of CSR acception. The social acceptance research of CSR is centered on the comparative analysis of Korean, Japanese and Chinese companies Social Activities in Vietnam. In addition, This paper seek to way of contribute to the sustainable development of Korean companies, and its harmonious cooperation with Vietnamese society through reviewing the CSR activities and direction of their CSR expectation. In the paper, linkage analysis was conducted with the results of the study on CSR value development process in Vietnam society and analysis of social responsibility values obtained from empirical studies. Through this, finally, we trying to search the value of social responsibility in Vietnam and its future directions. When we understand Vietnam's CSR, based on 'locality' of Vietnam, Northern and Southern can be understand on its different backgrounds. And it can be analyzed by their CSR characteristics of acception. As the result of this research, In the North, Foreign companies' CSR is understanded to be viewed from the corporate economic income and distribution. In the South, there is a strong tendency to understand CSR activities of foreign companies as marketing activities. On the whole, In northern Hanoi, there was a strong expectation in terms of 'employment improvement' and 'workers' working conditions'. In the South, there was a greater interest in improving the 'quality of life of residents' and 'consumer protection'. This is due to the influence of the economic system experienced during the process of different colonization, modernization and communization between the two regions. Since the Reform and Opening of Vietnam, Social Awareness of CSR seems that the regional differences were formed by the pace of economic development and the economic environment has played a role. In particular, the social acceptance of CSR values showed a slight difference in recognition between the North and South regions, but as both regions showed common hope for 'intervention in the role of government'. Therefore, Social Awareness of Vietnam's CSR is based on relation of 'government-society' formed from the 'Communitarianism'. As foreign investment flows more, CSR awareness and expectations in Vietnam's society will increase further. And the CSR expectations of local governments and stakeholder will be more complicated. It is time to check the needs of Vietnamese society in relation to locality of the social responsibility activities.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.27 no.4
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• pp.194-210
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• 2022

The monthly inventory of dissolved inorganic carbon (C_T) and its fluxes were simulated using a box-model for the southeastern Yellow Sea, bordering the northern East China Sea. The monthly C_T data was constructed by combining the observed data representing four seasons with the data adopted from the recent publications. A 2-box-model of the surface and deep layers was used, assuming that the annual C_T inventory was at the steady state and its fluctuations due to the advection in the surface box were negligible. Results of the simulation point out that the monthly C_T inventory variation between the surface and deep box was driven primarily by the mixing flux due to the variation of the mixed layer depth, on the scale of -40~35 mol C m^-2 month^-1. The air to sea CO₂ flux was about 2 mol C m^-2 yr^-1 and was lower than 1/100 of the mixing flux. The biological pump flux estimated magnitude, in the range of 4-5 mol C m^-2 yr^-1, is about half the in situ measurement value reported. The C_T inventory of the water column was maximum in April, when mixing by cooling ceases, and decreases slightly throughout the stratified period. Therefore, the total C_T inventory is larger in the stratified period than that of the mixing period. In order to maintain a steady state, 18 mol C m^-2 yr^-1 (= 216 g C m^-2 yr^-1), the difference between the maximum and minimum monthly CT inventory, should be transported out to the East China Sea. Extrapolating this flux over the entire southern Yellow Sea boundary yields 4 × 10⁹ g C yr^-1. Conceptually this flux is equivalent to the proposed continental shelf pump. Since this flux must go through the vast shelf area of the East China Sea before it joins the open Pacific waters the actual contribution as a continental shelf pump would be significantly lower than reported value. Although errors accompanied the simple box model simulation imposed by the paucity of data and assumptions are considerably large, nevertheless it was possible to constrain the relative contribution among the major fluxes and their range that caused the C_T inventory variations, and was able to suggest recommendations for the future studies.

• Korean Journal of Environmental Biology
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• v.40 no.1
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• pp.112-123
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• 2022

To assess the influence of environmental factors on the phytoplankton community structure and total phytoplankton biomass during four seasons in 2014, we investigated the abiotic and biotic factors at 25 stations in the Busan coastal region. The phytoplankton community and total phytoplankton biomass were strongly dependent on the discharge from the Nakdong River, and the high density of phytoplankton was related with the introduction of the Tsushima Warm Current (TWC), particularly in the thermohaline fronts of the fall season. The relationship between the salinity and nutrient (Dissolved inorganic nitrogen=DIN: R²=0.72, p<0.001 and Dissolved inorganic silicon=DSi: R²=0.78, p<0.001) highly correlated with the river discharge, implying that those nutrients have played a crucial role in the growth of diatom and cryptophyta. The total phytoplankton biomass was highest in the summer followed by autumn, spring, and winter. Diatom and cryptophyta species were dominant species during the four seasons. Additionally, there were strong positive correlations between Chlorophyll a and total phytoplankton biomass (R²=0.84, p<0.001), cryptophyta (R²=0.76, p<0.001) and diatom (R²=0.50, p<0.001), respectively. In particular, we found that there were significant differences in the nutrients, phytoplankton community compositions, and total phytoplankton biomass between the inner and the outer coastal region of Busan, depending on the amount of river discharge from the Nakdong River, particularly during rainy seasons. Therefore, the seasonal change of TWC and river discharge from the Nakdong River serve an important role in determining phytoplankton population dynamics in the Busan coastal region.