• Journal of the Korean Geosynthetics Society
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• v.17 no.1
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• pp.21-31
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• 2018

This paper analyzes the displacements of CFRD which was completed by field measurement. It is to understand the deformation behavior of the dam body according to the water level change from the impounding time. And it was compared with numerical analysis results. As a result of measuring the behavior of the dam crest and downstream slope according to impounding, horizontal displacements in axis direction of the dam, upstream and downstream displacements and settlements occurred mostly when the water level reaches about half of the dam height. The displacements continued until the water level reached its maximum. After that, it showed a constant convergence regardless of the water level. Horizontal displacements of the face slab which is the most important in CFRD were similar at all locations. The Horizontal displacements of the face slab showed the trends of increasing in winter and decreasing in summer due to the effect of the outside temperature before impounding. Also, the displacements increased until the water level reached about half of the dam height. After that, they decreased with rising in water level. As a result, the face slab behaviors according to seasonal change after impounding as well as water level condition. It is judged because of the material characteristics of the concrete slab. Numerical analysis showed slightly different maximum settlement and depth of occurrence from the measuring data after construction of the dam. It is considered that this is due to various design and construction differences such as the estimation of input parameters in analysis, construction period, and the layer thickness of construction. For the overall period of the dam, the settlements were mostly completed during the construction period and some settlements occurred in the early days of impounding and then converged.

• Journal of Environmental Health Sciences
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• v.46 no.1
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• pp.35-44
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• 2020

Objectives: The purpose of this study was to compare the health status of residents who were exposed to the Iksan industrial area in the living environment and those who were not exposed to such a source of industrial activity through a questionnaire survey designed to appraise the residents' health levels. Method: The authors conducted a health questionnaire survey of 1,012 residents around Iksan regarding their personal information, physician-diagnosed disease history, odors experienced, and more. Logistic regression was performed to identify the associations between hazardous chemical exposure and physician-diagnosed diseases. Result: Logistic regression shows significant differences in allergic rhinitis, cardiovascular disease, hypertension, dyslipidemia, liver disease, and osteoporosis. Odors were experienced by 88.0% of the survey group. The seasons were summer (71%) and spring (24.9%). Conclusion: For allergic rhinitis, cerebral cardiovascular disease, and hypertension, which were significantly higher in the case group than in the control group in the disease diagnosis and disease treatment history of physicians, it was difficult to completely eliminate the association with odor exposure in the Iksan Industrial Complex. It is considered that it has affected nearby residents. This study means that a correlation between chronic diseases has been found through regression analysis, and furthermore, this result can be used as a basis for sampling for secondary epidemiological surveys.

• Journal of Environmental Science International
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• v.20 no.7
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• pp.857-872
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• 2011

The variation of groundwater level in Jeju Island is analyzed with the data of precipitation observed from 48 monitoring post and groundwater level observed from 84 monitoring wells during 2001 to 2009. The groundwater level rises in summer and falls in winter. The rise of groundwater level by precipitation is fast and small in the eastern region and slow and large in the western region. However, the speed of fall during the period of no rain is slower in the eastern region than in the western region. It tells that permeability is greater in the eastern region than in the western region. In this paper, we set up the base level of groundwater and calculate recharge volume between the base level and groundwater surface. During the period, the average recharge volume was $9.83{\times}10^9m^3$ and the maximum recharge volume was $2.667{\times}10^{10}m^3$ after the typhoon Nari. With these volume and the recharge masses obtained by applying the recharge ratio of 46.1%, estimated by Jeju Province (2003), the porous ratio over the whole Jeju Island is 16.8% in average and 4.6% in the case of maximum recharge volume just after typhoon Nari. A large difference in the two ratios is because that it takes time for groundwater permeated through the ground just after rain fall to fill up the empty porous part. Although the porous ratios over the whole Jeju Island obtained in this way has a large error, they give us the advantage to roughly estimate the amount of recharged groundwater mass directly from observing the groundwater level.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.4
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• pp.36-47
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• 2008

The purpose of this study is to classify and assess the characteristics of urban Korean parks by on-site park users' reactions, such as satisfaction, preference and cognitive image of the park and park facilities. The park facilities are classified into five types of satisfaction: management status, activity facilities, convenient facilities, circulation and density, and landscape facilities. The park users are satisfied with conversation, rest and relaxation in the parks, but not satisfied with studying and nature experience. The behaviors in the park are classified as park activities, emotional and experiential activities, and nature activities. The results indicate that the images of the parks are stable, comfortable and natural. There are three factors to classifying the park images: nature-harmony, openness, uniqueness. Preferences for each parks are generally good. According to the criteria such as satisfaction of park facility, behavioral satisfaction, images and preference for each park, the 12 parks are divided into 5 different types: multi-purpose park, well-balanced park with natural elements, urban open space, park to be improved, and ecological park. The characteristics of each park was analyzed and categorized. This study dealt with only the parks in Seoul and its environs, and the survey was only done during the summer season. Therefore, further research is necessary to enlarge and generalize the results of this study, considering seasonal and regional variations.

• Korean Journal of Ecology and Environment
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• v.39 no.1 s.115
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• pp.52-61
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• 2006

The aim of this study was to analyze the seasonal patterns of zooplankton community dynamics in the lower Nakdong River (Mulgum, RK; river kilometer; 27 km from the estuarine barrage), with a Self-Organizing Map (SOM) based on weekly sampled data collected over ten years(1994 ${\sim}$ 2003). It is well known that zooplankton groups had important role in the food web of freshwater ecosystems, however, less attention has been paid to this group compared with other community constituents. A non-linear patterning algorithm of the SOM was applied to discover the relationship among river environments and zooplankton community dynamics. Limnological variables (water temperature, dissolved oxygen, pH , Secchi transparency, turbidity, chlorophyll a, discharge, etc.) were taken into account to implement patterning seasonal changes of zooplankton community structures (consisting of rotifers, cladocerans and copepods). The trained SOM model allocated zooplankton on the map plane with limnological parameters. Three zooplankton groups had high similarities to one another in their changing seasonal patterns, Among the limnological variables, water temporature was highly related to the zooplankton community dynamics (especially for cladocerans). The SOM model illustrated the suppression of zooplankton due to the increased river discharge, particularly in summer. Chlorophyll a concentrations were separated from zooplankton data set on the map plane, which would intimate the herbivorous activity of dominant grazers. This study introduces the zooplankton dynamics associated with limnological parameters using a nonlinear method, and the information will be useful for managing the river ecosystem, with respect to the food web interactions.

• Atmosphere
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• v.28 no.1
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• pp.99-112
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• 2018

In this study, the accuracy of ocean analysis data, which are produced from the Korea Meteorological Administration (KMA) Nucleus for European Modelling of the Ocean/Variational Data Assimilation (NEMO/NEMOVAR, hereafter NEMO) system and the HYbrid Coordinate Ocean Model/Navy Coupled Ocean Data Assimilation (HYCOM/NCODA, hereafter HYCOM) system, was evaluated using various oceanic observation data from March 2015 to February 2016. The evaluation was made for oceanic thermal environments in the tropical Pacific, the western North Pacific, and the Korean peninsula. NEMO generally outperformed HYCOM in the three regions. Particularly, in the tropical Pacific, the RMSEs (Root Mean Square Errors) of NEMO for both the sea surface temperature and vertical water temperature profile were about 50% smaller than those of HYCOM. In the western North Pacific, in which the observational data were not used for data assimilation, the RMSE of NEMO profiles up to 1000 m ($0.49^{\circ}C$) was much lower than that of HYCOM ($0.73^{\circ}C$). Around the Korean peninsula, the difference in RMSE between the two models was small (NEMO, $0.61^{\circ}C$; HYCOM, $0.72^{\circ}C$), in which their errors show relatively big in the winter and small in the summer. The differences reported here in the accuracy between NEMO and HYCOM for the thermal environments may be attributed to horizontal and vertical resolutions of the models, vertical coordinate and mixing scheme, data quality control system, data used for data assimilation, and atmosphere forcing. The present results can be used as a basic data to evaluate the accuracy of NEMO, before it becomes the operational model of the KMA providing real-time ocean analysis and prediction data.

• Korean Journal of Remote Sensing
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• v.36 no.3
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• pp.411-423
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• 2020

Localized solar irradiance is normally derived from atmospheric transmission influenced by atmospheric composition and conditions of the target area. Specially, for the area with complex coastal lines such as Taean gun, the accurate estimation of solar irradiance requires for in depth analysis of atmospheric transmission characteristics based on the localized vertical profiles of the key atmospheric parameters. Using MODTRAN (MODerate resolution atmospheric TRANsmission) 6, we report a computational study on clear day atmospheric transmission and direct solar irradiance estimation of Taean gun using the data collected from 3 ground stations and radiosonde measurement over 93 clear days in 2018. The MODTRAN estimated direct solar irradiance is compared with the measurement. The results show that the normalized residual mean (NRM) is 0.28 for the temperature based MODTRAN atmospheric model and 0.32 for the pressure based MODTRAN atmospheric model. These values are larger than 0.1~0.2 of the other study and we understand that such difference represents the local atmospheric characteristics of Taean gun. The results also show that NRM tends to increase noticeably in summer as the temperature increases. Such findings from this study can be very useful for estimation and prediction of the atmospheric condition of the local area with complex coastal lines.

• Journal of Environmental Impact Assessment
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• v.24 no.1
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• pp.1-15
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• 2015

To mitigate the impacts of climate change on agricultural ecosystems, development of agricultural management for enhanced soil carbon sequestration is required. In this study, the effects of fertilizer types (chemical fertilizer and manure compost), cropping systems, and crop residue management on SOC(Soil Organic Carbon) sequestration were investigated. Summer corn and winter barley were cultivated on experimental plots under natural rainfall conditions for two years with chemical fertilizer and manure compost. Soil samples were collected conducted and analyzed for SOC for soil. To estimate long-term variation patterns of SOC, DNDC was run with the experimental data and the weather input parameters from 1981 to 2010. DNDC simulation demonstrated SOC reduction by chemical fertilizer treatment unless plant residues are returned; whereas compost treatments increased SOC under the same conditions and SOC increment was proportional to compost application rate. In addition, SOC further increased under corn-barley cropping system over single corn cropping due to more compost application. Regardless of nutrient input type, residue return increased SOC; however, the magnitude of SOC increase by residue return was lower than by compost application.

• The Korean Journal of Pharmacology
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• v.17 no.2
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• pp.37-45
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• 1981

The importance of thyroid hormones for the survival of rats in the cold is along-established fact. Hypothyroid animals are unable to survive in a cold environment. It was also reported that acute exposure of rats, guinea pigs and rabbits to cold produced an increased secretion of TSH and thereby thyroid hormone secretion within 10 to 30 min, but this increase of thyroid activity disappeared quite rapidly during warming. However, in human study no significant difference was found in the concentration of $T_4$, TSH and cortisol between summer and winter. But plasma $T_3$ concentration was increased significantly in winter in 56 adult men. On the other hand, it has been also known that catecholamines are important in the maintenance of body temperature of rat exposured to cold. Abundant evidences suggest that the sympathetic nervous system is involved in the activation of nonshivering thermogenesis and that thyroid hormone metabolism and secretion are influenced by catecholamines and consequently by the activity of the sympatheticadrenal system. Many of the metabolic effects of catecholamines are associated with an increase in the level of cAMP mediated through activation of adenylate cyclase which converts ATP to cAMP. Other studies have shown that thyroid hormones affect the amount of adenylate cyclase present in the adipose tissue. On the other hand. it was also reported that a particulate cAMP phosphodiesterase activity in fat cells was modulated by the action of thyroid hormones. The objective of the present study was to determine the interaction between thyroid activity and cyclic nucleotides during acute exposure to cold. Albino rats weighing around 200 g were used as the experimental animal. The room temperature group was kept at $25^{\circ}C$ and the cold-exposured group was kept at $4^{\circ}C$ for 1 week or 2 weeks. Each group was subdivided into three subgroups; control, KI, and MTU group. At the end of experiment the animals were etherized and blood was taken from abdominal aorta for $T_4,\;T_3$ and cyclic nucleotides. The determinations of $T_3,\;T_4$ and cyclic nucleotides were carried out with a radioimmunoassay(RIA) method. The results were summerized as followings. 1) A significant increase of thyroid weight was observed in rats exposured to cold for 2 weeks. Furthermore, in rats administered MTU while to exposure to cold the thyroid weight was also increased significantly. 2) After 2 weeks $T_3$ concentration in the plasma of cold-exposured rats was significantly increased in KI group and MTU group as well as in control group. On the contrary, after 2 weeks of cold exposure $T_4$ level was decreased in control group. 3) In the case of cyclic nucleotides, plasma cAMP was increased in the control group after 1 or 2 weeks of cold exposure. However, cAMP level in plasma was rather significantly decreased in KI group and MTU group as well as in control group.

• Journal of Fashion Business
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• v.6 no.6
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• pp.19-33
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• 2002

In the middle of economic and mental riches in the 21st century, the importance of well being and the pursuit of happiness are emerging as the new trend. Thus the lifestyle that values comfortable and practical naturalness and intrinsic merits has come to influence the human life rather than the old showing-off and formal desire. In addition to this, the spread of the five day week has given more leisure time, which has led to the increasing interest in health and leisure. The interest in sports has skyrocketed since the successful holding of the 2002 Korea and Japan World Cup event. All these changes to the lifestyle have contributed to the fusion of luxury wear and sports wear. As the result of the consumers in the 21st century having more classified and upgraded way of living thanks to the settlement of the above-mentioned lifestyle and the enlargement of the leisure sports culture, there has appeared the wellness kin, who value the importance of life and the nature and believe in the idea that they can reconstruct the environment in the way they can enjoy their lifestyle and pursue happiness. They favor healthy fashion items and think much of exercise, nutrition, and rest. They pursue the natural and comfortable style, whose ideas came from simple exercises such as health training and yoga and the easy and comfortable look observed at resorts. Their fashion style can be divided into three of fitness fashion, yoga fashion and resort fashion. First, the boxer fashion is characterized by the relaxing design and practicality. The major items of the fashion include running shirt-styled upper clothes, training pants, hooded shirts and sneakers. Simple and comfortable look should be induced from the combination of the items. Second, the yoga fashion was motivated by the comfortable yoga wear. It advocates stress-free spirit and comfortable and stable naturalism. Along with the advantages of the good feeling to wear and the functionality to help exercise better, the yoga fashion gives the wearer enough room to move around in, using the unique lines. Third, the resort wear refers to the kinds of clothes you tend to wear at the beach and the park. There are various kinds of the resort look; bathing suits, the beach wear you can wear with the bathing suit, the resort evening wear, the full-side look that you try on top of the bathing suit and is made of the same material of the bathing suit, and the marine look, the symbol of the summer. In short, the study attempted to investigate many trends occurring as the result of human recent increasing interest and concern in the quality of life, and the impacts of them on the fashion world. This kind of research that examines the background of the times and society will help to grasp with the fashion trends of the present and the future. And more studies should be conducted on the development of new and original design in clothes fashion, which reflects the characteristics identified in this kind of research.