• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.4
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• pp.11-23
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• 2011

Mountain streams, which are major components of an entire river network, play an important role as the source of water, sediment, coarse and fine organic matter, and nutrients for lowland rivers. Therefore, dynamics and downstream linkages of each compartment of the mountain stream can be essential for watershed management in catchment scale. The dynamics and downstream linkages are understood as a development of step-pool sequences along a river course. Recently, stream restoration after flooding event often employ the development of step-pool sequences in the world. In this paper, we 1) examined the geomorphic characteristics and the role of step-pool sequences in steep mountain streams by reviewing the results of past studies, and 2) introduced the case studies of stream restoration using step-pool sequences, and finally 3) addressed design methods considering geometry and stability of artificial step-pool sequences for stream restoration. Step-pool sequences play an important role not only as roughness with energy dissipation but also as heterogeneity of stream feature for aquatic habitat. Step-pool sequences, even if they are constructed artificially along a stream, may be effective for small stream restoration considering eco-friendly torrent controls. So far the artificial step-pool sequences were employed for mountainous streams, but those would be applied to urban stream.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.6
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• pp.490-494
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• 2020

Sulphur hexafluoride (SF₆) is mostly used as a current-insulating medium in gas-insulated switchgears (GIS), owing to its excellent dielectric strength and arc-extinguishing performance. The global warming potential (GWP) of SF₆, however, is 23,900 times that of CO₂, and its life time in the atmosphere is 3,200 years. For these reasons, new eco-friendly gases to replace SF₆ are required. In this study, the partial discharge (PD) characteristics of green gas for grid (g³) and dry air (N₂/O₂) were analyzed to compare with those of SF₆. A PD electrode system was designed to simulate the protrusion defect in GISs and fabricated for experimentation. To compare the PD characteristics of each gas, the discharge inception voltage (DIV), discharge extinction voltage (DEV), discharge magnitude, discharge pulse number, and phase pattern were analyzed. Results from this study are expected to provide fundamental materials for the design of eco-friendly GISs.

• Journal of Korean Society of Rural Planning
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• v.22 no.2
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• pp.67-75
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• 2016

This Research was carried out to investigate landscape characteristics of the traditional Chinese village through the landscape analysis. The Purpose of this study was to offer suggestions for improving Korea's traditional village scenery. This research was conducted by analysis about an important component of the landscape in Ping-shan traditional village. It was studied natural landscape, life landscapes, agricultural production landscapes and symbols landscape. This study was carried out through literature research, field research and interviews. The results of Chinese traditional village's landscape characteristic was First, Ping-shan traditional village was located on the basis of Feng-Shui settings. Second, Ping-shan traditional village was clan-based. Third, It is composed of a large green space on the outskirts of the village. Fourth, Ping-shan traditional village was a typical channel village. Fifth, Ping-shan traditional village was a living landscape with various features. sixth, Ping-shan traditional village was a lot of space to agricultural production, most of the arable land surround village. Suggestions for improving Korea's traditional village scenery are as follows ; First, proposes actively re-design on the base of defense fengshi landscape interpreted as a modern sense. Seconds, when large-scale farmland project is established in Korea, you can expect to gain knowledge from traditional Chinese village spacing. Thirds, It seems to require a study of the public space for festival. in the case of china, ancestral shrine space is center and space for festival. Fourth, It was important to seek knowledge about protection for frequent in flood plains in Korea's traditional village. Ping-shan traditional village was well-known for housing with contact water, connected channels and beautiful defense pond. Fifth, for improving Korea's traditional village scenery, we need to make various focus landscape features. Most of the visitors to Ping-shan traditional village was interested in the big and small beautiful landscapes and shelters.

• Journal of Korean Society of Rural Planning
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• v.23 no.4
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• pp.99-110
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• 2017

This study is to analyze the spatial structure and POE of Jungja(pavilion) shelter for rural village regeneration. 14 Jungja shelter space at rural villages in Gyungbuk province, were investigated. An interview questionnaire was conducted for total 139 residents as POE. The use behavior and satisfaction for Jungja shelter space, were investigated. The statistical analysis were mean of satisfactions, reliability, factor analysis, and multiple regression analysis. The results and discussions can be objective data for rural village regeneration. In satisfaction level, 'Continuous use intention'(3.99), 'Well-suited approach'(3.87), and 'Helpful in resident living'(3.84) were shown to be high points of agreement in 5 point Likert type scale. But, the mean points were low as 2.01 in 'Surrounding landscape', 'Creation of green areas'(3.22), and 'Traffic safety'(3.22), respectively. Within use satisfaction, 5 factors were categorized, 'Use', 'Safety', 'Facility', 'Management' and 'Users'. By the result of multiple regression analysis, variables of 'Continuous use', 'Convenient location', and 'Image improvement', were shown to be main affecting variables to overall satisfaction. Furthermore, in spatial structure analysis, 4 types were categorized with the aspect of landform, roads, and location in village. The levels of satisfaction were shown to be high in village type of semi-open, road type of circular, and location type of center/back. Conclusively, these findings could be utilized as basic data and useful tool of space-structural satisfaction analytic method, and for each stage of planning/design and remodeling for rural village regeneration.

• Journal of Korean Society on Water Environment
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• v.20 no.3
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• pp.301-306
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• 2004

The present water quality standards for agricultural were established without considering the effects of water quality on the safety, growth, yield and quality of crops. This study was carried out to investigate the effects of irrigation water quality on the growth, yield, and grain quality of rice, and to acquire basic knowledges to set up water quality standards for irrigation. The field and pot experiments were conducted with irrigation water that was previously adjusted four concentrations (control, 5, 10, 20 mg/L) and six concentrations (control, 5, 10, 15, 20, 30 mg/L) by $NH_4NO_3$ solution and replicated three and four times with randomized block design, respectively. The results of this study showed that the inorganic nutrient of rice plant, rice protein contents and number of panicle tended to increase as the T-N concentration in irrigation water was increased. In addition, grain yield at T-N 10 mg/L and 20mg/L were significantly higher than the control at the field experiment. From the pot experiment at T-N 30 mg/L, the percentage of head rice was slightly lower due to the increase of green kernel and white belly/core kernel.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.23 no.3
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• pp.1-1
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• 1987

The accurate prediction of the ship wave resistance is very important to design ships which operate satisfactorily in a wave environment. Thus, work should continue on development and validation of methods to compute ship wave patterns and wave resistance. Research efforts to improve the prediction of ship waves and wavemaking resistance are categorized in two major areas. First is the development of higher-order theories to take account of the nonlinear effect of the free surface condition and improved analytical treatment of the body boundary condition. Second is the development of direct numerical methods aimed at solving body and free-surface boundary conditions as accurately as possible. A new formulation of the slender body theory for a ship with constant speed is developed by Maruo. It is quite different from the existing slender ship theory by Vossers, Maruo and Tuck. It may be regarded as a substitute for the Neumann-Kelvin approximation. In present work, the method of asymptotic expansion of the Kelvin source is applied to obtain a new wave resistance formulation in fluid of finite depth. It takes a simple form than existing theory.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4137-4144
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• 2010

In this study, the simulations were carried out to show the effect of the EGR configuration in a passenger diesel engine with 2-stage turbocharger on the EGR rate. The AMESim and IFP Engine Library were used to make the program for the simulation. Three EGR configurations, HPL(high pressure loop), LPL(low pressure loop), and SLPL(semi low pressure loop), were considered. The EGR rate in the HPL and LPL EGR routes were 6.4% and 10.0% respectively but the rate in SLPL route was 18.0% and their air/fuel ratio for all three cases was 21. Therefore the SLPL EGR configuration may be positively considered in the design of the passenger diesel engine with 2-stage turbocharger.

• Nutrition Research and Practice
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• v.10 no.1
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• pp.89-98
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• 2016

BACKGROUND/OBJECTIVES: Observational studies suggest that an association between vegetable consumption and coronary heart disease (CHD). However, the results are inconsistent. This study aimed to investigate the daily intake of vegetables on a national level and its effect on the risk of CHD risk, as determined by the Framingham Risk Score (FRS). SUBJECTS/METHODS: This study was conducted a cross-sectional design of 2,510 male adults 40-64y of age who participated in the 2007-2009 Korean National Health and Nutrition Examination Survey. Daily intake of vegetable was assessed by 24-h recall, and the consumption frequency of vegetables was determined using a food frequency questionnaire. The odd ratio of CHD risk according to daily intake and frequency of vegetables was analyzed. RESULTS: Total vegetable intake was inversely and significantly associated with the risk of CHD (Model 1: 4th vs. 1st quartile, OR = 0.74, 95% CI = 0.58-0.96, P for trend = 0.0015), and the significant relationship with CHD risk remained even after adjusting for potential confounders (Model 3: 4th vs. 1st quartile, adjusted OR [aOR] = 0.69, 95% CI = 0.49-0.95, P for trend = 0.0492). Subjects in the higher quartiles of non-salted vegetable intake had 31% lower odds of the risk of CHD compared to those in the lowest quartile after adjusting for various potential confounders in model 3 (aOR = 0.69; 95% CI = 0.49-0.97, P for trend = 0.0478). No significant associations between the frequency of vegetable intake (total, green, white and red vegetable) and the risk of CHD were found. CONCLUSIONS: The major results of this study indicate that higher vegetable intake may help prevent CHD in Korean men.

• Journal of Fashion Business
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• v.23 no.5
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• pp.48-66
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• 2019

The purpose of this thesis was to investigate the similarities between religious costumes and Kazakh and Tajik minority women's costumes in the Chinese northwestern minority population that believes in both Islam and Shamanism. The research was conducted by investigating the forms, colors, and patterns of 240 representative costume pieces and making quantitative comparisons between religious and traditional costumes. The results showed that the Kazakh and Tajik costumes were similarly formed, both intended to cover the human body. Both the Islamic and traditional headdresses were also similarly shaped. In terms of color, black, white, green, and blue were found frequently in the Islamic religious costumes, as were red and yellow. Red, white, and brown, ascribed to the colors of shamanism, signifying incantations, were also frequent, indicating that this was engrained in their lives. A review of the traditional costumes revealed the patterns of Islam. Plants, geometry, abstraction, and letter patterns were dominant, whereas the meaning of the Islamic patterns, rebirth, sun, life, and hope, influenced the traditional costume patterns. Patterns associated with incantations, like the animal horns shown in the shamanism religious costumes, were persistently observed even after the people were converted to Islam. This study on the similarities between religious and traditional costumes in the Chinese minority might help us understand the connection between religious and traditional costumes and elucidate the cultural costume transition process.

• Journal of the Korea Convergence Society
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• v.10 no.11
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• pp.309-320
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• 2019

Waterfront revitalization is an important issue for the downtown regeneration of harbor cities. The purpose of this study was to derive implications for waterfront revitalization project to regenerate the downtown of harbor city. Theoretical considerations and case studies were conducted on Darling Harbour in Sydney and Rose Kennedy Greenway in Boston. The results of the case analysis are as follows. (1) The land use, buildings and facilities for leisure and amusement that provide public access and various experiences were constructed and historical heritage was actively utilized. (2) The open spaces in various sizes and characteristics including waterfront walkways, parks, plazas and green spaces were created. (3) The connection between downtown and waterfront was improved in terms of pedestrian space and townscape in order to create synergistic effect between downtown and waterfront.