• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.3
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• pp.13-26
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• 2015

Many urban areas in Korea suffer from repeated flood damage during intensive rainfall due to an increase in impervious areas caused by rapid urbanization and deteriorating sewage systems. A centralized stormwater management system has caused severe flood damage in an area that has proven unable to accommodate recent climate change and a rise in precipitation. Most flooding prevention projects that have been recently implemented focus on increasing drainage system capacity by expanding the size of sewer pipes and adding pumping stations in downstream areas. However, such measures fail to provide sustainable solutions since they cannot solve fundamental problems to reduce surface runoff caused by urbanization across the watershed. A decentralized stormwater management system is needed that can minimize surface runoff and maximize localized retention capacity, while maintaining the existing drainage systems. This study proposes a stormwater management corridor for the flood-prone watershed in the city of Dongducheon. The corridor would connect the upstream, midstream, and downstream zones using various methods for reducing stormwater runoff. The research analyzed surface runoff patterns generated across the watershed using the Modified Rational Method considering the natural topography, land cover, and soil characteristics of each sub-watershed, as well as the urban fabric and land use. The expected effects of the design were verified by the retainable volume of stormwater runoff as based on the design application. The results suggest that an open space network serve as an urban green infrastructure, potentially expanding the functional and scenic values of the landscape. This method is more sustainable and effective than an engineering-based one, and can be applied to sustainable planning and management in flood-prone urban areas.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.6
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• pp.410-418
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• 2017

The stability of low-crested structure (LCS) and overtopping discharge over a seawall behind the LCS are influenced by the water level behind the structure. Hence, the experimental results can be distorted unless the increase of water level is known when two-dimensional experiment is carried out. In order to estimate increase of the mean water level behind the low-crested structure, this study applied a hybrid technique that combined results of two-dimensional model test and hydrodynamic numerical modeling based on the relationship between the water level and discharge. By using this technique, the mean water level increase and flow field can be obtained almost at the same time, which resolved the above problem considerably. In addition, this method can provide an approximate information about the outflow velocity from the openings of the structure, which is helpful for selecting appropriate planar configuration of the low-crested structure.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.1058-1062
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• 2005

통상 방조제 배수갑문의 방류능력은 위어공식 또는 오리피스공식을 이용하여 산정하는데, 이 경우 지형특성, 배수갑문 형상에 따른 흐름의 간섭현상, 유입부와 유출부의 형상 등이 방류량에 미치는 영향을 고려하지 못한다. 본 연구에서는 도류벽, 배수문, 물받이 등 방조제 배수갑문의 형상과 배치가 방류량에 미치는 영향을 상용 프로그램인 FLOW-3D를 이용하여 정량적으로 해석하였다. 이를 통해 배수갑문의 방류능력과 유황을 개선할 수 있는 방안을 도출하였다. 본 연구에서는 시화조력발전소를 대상으로 배수갑문의 방류능력 개선에 3차원 수치모의가 효과적으로 적용될 수 있음을 보였다. 본 연구에서 도출한 주요 결론은 다음과 같다. 1) 유출부측의 물받이길이를 40 m 증가시킴에 따라 전체 방류량은 계획안에 비해 약 $10\% 증가하는 것으로 나타났다. 2) 물받이 끝과 원지반의 연결부 사면을 1:1에서 1:5의 완경사로 변화시킴에 따라 전체 방류량은 약 $2\%$ 증가하는 것으로 나타났다. 3) 배수문과 수차발전 구조물 사이의 유선형 연결구조물을 제거함에 따라 전체 방류량은 약 $3\%$ 증가하는 것으로 나타났다. 4) 도류벽의 접근각도를 $10^{\circ}$ 감소시키거나 증가시킴에 따라 전체 방류량은 약 $5\% 감소 또는 증가하는 것으로 나타났다. 본 연구는 배수갑문의 설계시 방류능력 개선을 위해서는 수리학적 검토가 필요하며 수치모형실험이 수리모형실험과 더불어 유용한 해석도구로 이용될 수 있음을 보인 것으로, 이후 관련 구조물의 설계시 참고자료로 이용 가능할 것으로 사료된다.다. 실험 결과, Escarameia와 May가 제안한 공식을 더 확장하여 적용할 수 있는 실험 공식으로 개선하였으며 다양한 조건에 대한 실험을 수행하여 보다 정밀한 공식으로 개선할 수 있었다.$10,924m^3/s$ 및 $10,075m^3/s$로서 실험 I의 $2,757m^3/s$에 비해 통수능이 많이 개선되었음을 알 수 있다.함을 알 수 있다. 상수관로 설계 기준에서는 관로내 수압을 $1.5\~4.0kg/cm^2$으로 나타내고 있는데 $6kg/cm^2$보다 과수압을 나타내는 경우가 $100\%$로 밸브를 개방하였을 때보다 $60\%,\;80\%$ 개방하였을 때가 더 빈번히 발생하고 있으므로 대상지역의 밸브 개폐는 $100\%$ 개방하는 것이 선계기준에 적합한 것으로 나타났다. 밸브 개폐에 따른 수압 변화를 모의한 결과 밸브 개폐도를 적절히 유지하여 필요수량의 확보 및 누수방지대책에 활용할 수 있을 것으로 판단된다.8R(mm)(r^2=0.84)$로 지수적으로 증가하는 경향을 나타내었다. 유거수량은 토성별로 양토를 1.0으로 기준할 때 사양토가 0.86으로 가장 작았고, 식양토 1.09, 식토 1.15로 평가되어 침투수에 비해 토성별 차이가 크게 나타났다. 이는 토성이 세립질일 수록 유거수의 저항이 작기 때문으로 생각된다. 경사에 따라서는 경사도가 증가할수록 증가하였으며 $10\% 경사일 때를 기준으로 $Ro(mm)=Ro_{10}{\times}0.797{\times}e^{-0.021s(\

• Journal of Navigation and Port Research
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• v.30 no.1 s.107
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• pp.9-15
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• 2006

At the adjacent sea area of Busan Central Wharf, a variety of vessels, such as middle-large passenger ships, small hugh speed crafts, container ships, cargo ships and working boats as well as small miscellaneous vessels are freely sailing comparatively without special rules and marine traffic control. In this research, we analyzed traffic stream and navigational characteristics cf main traffic route based on statistics and distribution of tracks by ship's type and tonnage cf the passing vessels after conducting marine traffic survey twice using exclusive software. We examined the traffic safety of the passing vessels by classifying the sea area by each function based on the analysis about this traffic situation, and analyzing the effect by designating 'Inner passage'. We also studied the plan for the effective rearrangement cf Central Wharf considering basically the traffic safety of arrival and departure in a point of view of navigators.

• Korean Journal of Poultry Science
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• v.19 no.3
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• pp.125-136
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• 1992

This study was conducted to estimate the effect of dietary alfalfa meal on the contents of egg yolk cholesterol, the levels of egg yolk pigmentation and the performance of laying hens. Alfalfa meal which was alternated wheat bran was supplied 0, 3.5 and 7%, respectively. Total 192 brown laying pullets of 47 weeks old were randomly assigned to the wire cages from July 23 to October 7, 1991 for 10 weeks. The results obtained were summarized as follows ： 1. The egg production was highest at 3.5% alfalfa meal level during the entire period. But there was no significant difference among treatments. 2. Egg weight increased in treatments 3.5 and 7% alfalfa meal supplementation significantly. (P<0.01). 3. Even though there was no significant difference, the daily egg mass was the highest at 3.5% of alfalfa meal level. 4. Daily feed intake was the highest at 3.5% of alfalfa meal level. However, feed conversion rate was the lowest among treatments. 5. The feed cost per kg egg mass in the treatment of 3.5% alfalfa meal was significantly lower than the other treatments. (P<0.05). 6. Shell thickness and shell weight in terms of egg shell quality were increased as the levels of alfalfa meal were increased. But there was no significant difference among treatments. 7, The egg yolk Pigmentation was improved significantly as the level of alfalfa meal was increased (P<0.01). 8.899 yolk cholesterol contents were decreased in the treatments of 3.5 and 7% alfalfa meal supplementation compared with those in the treatment of wheat bran only(P >0.05). The results of this study indicate that 3.5% alfalfa meal level was most effective and economical in laying hen.

• KEPCO Journal on Electric Power and Energy
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• v.5 no.4
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• pp.249-256
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• 2019

A full-scale test line was established to verify the electrical environmental interferences caused by the HVDC ±500 kV Double Bipole overhead transmission line with metallic return conductor, which is scheduled for construction in Korea and the fullscale test was conducted for one year. And through the human perception test of the DC electric-field under the HVDC Double Bipole line, the threshold value at which the human detects DC electric field was investigated to verify the validity of the design guide for the HVDC ±500 kV Double Bipole overhead transmission line. The polarity configuration of the HVDC ±500 kV Double Bipole test line was arranged diagonally with the same polarity in terms of the electrical environment disturbance and operation. The test line utilized the 6-bundle arrangement to prevent the corona discharge taking into account the domestic social acceptability. The test results show that the HVDC ±500 kV Double Bipole transmission line generated very little corona discharge from the conductors. Therefore, both DC electric field and ion current density met the domestic design guide for DC overhead transmission lines. Also, the human perception test of DC electric fields under the test line showed that 70% of participants did not recognize the DC electric field even when exposed to 23 kV/m.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.5
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• pp.93-107
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• 2018

The concepts of geotourism and geoparks have emerged due to the paradigm shift in tourism and the increased recognition of geosites and geoheritage as legacies that must be protected and preserved. The number of geoparks designated by UNESCO and national governments is increasing globally. The purpose of this paper is to propose directions for enhancing Jeju Geopark to perform as a geological educational venue. This study reviewed the present conditions of the education and communication, the media, and the facilities of the geopark with respect to the required conditions to be effective for geological education. Data surveys, field surveys, visitor questionnaires, and interviews were conducted to examine the educational and guidance system of the geopark, the physical space configuration, and the operation and management methods. The research process is as follows. First, the study analyzed the status of the education and communication in Jeju Geopark, according to the criteria of the UNESCO GGN, using data acquired from the survey. Second, the study analyzed and evaluated the educational and communication facilities, and media, focusing on four aspects of the geopark: the geo-trail, spatial composition and layout, communicational and educational facilities, and the system and design of signboards. Third, the study assessed the perception and satisfaction of visitors to the geopark. Fourth, the study summarized the potential and limitations of the Jeju Geopark through in-depth interviews. The four analyses showed that enhancements in the exploration environment, communication, media, and operation and management system are all necessary for effective geological education. Based on these results, this study suggests directions for enhancing the geopark in the four following aspects. Management and maintenance must be improved to meet UNESCO criteria, while the improvements in the visiting environment quality, the supplementing of communication and facilities, and enhancements in the organization and system of operation and management also must be taken on.

• Journal of Navigation and Port Research
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• v.37 no.3
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• pp.291-298
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• 2013

The purpose of this study was to analyze perceptions to hindering factors and development factors for water leisure activation. In order to accomplish the study purpose, this study employed a survey method with water leisure participants and employees from 6 regions(participants=205, employees=117). The data were analyzed using independent t-tests at a=.05 and following findings were derived from current study. First, among 20 hindering factors, water leisure participants had higher levels of perceptions than employees in licence system, limited activation regulation, departure report regulation, absence of exclusive organization, lack of providing information, lack of participative events and support systems. Second, relatively highly perceived hindering factors included departure report regulation, limited activation regulation, licence system, lack of government support, lack of mooring facility and lack of exclusive charged organization, in order. Third, the important development factors perceived by participants included support for licence and education and diversified water leisure programs but those perceived by employees included placement of educated experts and related event host and publicity. Finally, relatively highly perceived development factors included activation of free experience, promotion of marina development, support for licence and education, diversified programs and support for water leisure business. Accordingly, the findings provided fundamental information that both central and regional government can utilize for further activating water leisure. In addition, several development strategies were discussed on financial support, facility support, human resource support, education support and event support perspectives.

• The Journal of the Korea Contents Association
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• v.11 no.6
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• pp.419-427
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• 2011

As for the anti-terrorism bills, which were submitted to the National Assembly, the mobilization of anti-terrorism commando, which was designated or established by the National Defense Minister, is mobilized the military troops without being based on marital law in light of the constitutional law, thereby possibly violating the constitution, first of all, with regards to mobilization of anti-terrorism commando, which was formed with military troops. The anti-terrorism commando is the military force, which was trained professionally for the anti-terrorism activity. Thus, the violation of human rights may be greatly reduced rather than what general soldiers are putted in the public-order activity such as anti-terrorism. However, it is thought to be desirable to make it possible for the input of special forces, which were trained professionally in relation to anti-terrorism activity, through constitutionally revising the constitutional law. As for the provision of 'support for military troops' in the anti-terrorism bill, what is a case that the nation's important facilities and multi-use facilities are difficult to be protected from terror with the anti-terrorism commando and police force needs to be constitutionally regarded as resulting in reaching the level enough to correspond to 'a state of national emergency equivalent to wartime incident.' Thus, enacting the future anti-terrorism law, it is thought to be unnecessary for having the provision of 'support for military troops' with receiving criticism obstinately for possibly violating the constitution.

• Korean Journal of Poultry Science
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• v.36 no.3
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• pp.201-206
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• 2009

This study was carried out to investigate dietary effects of illite on humoral immune response against Salmonella typhimurium flagella in Hyline Brown laying hens. Total of twenty eight 36-week-old hens were divided into two groups; The first was fed commercial diet as control and the other was fed diet containing 2 % illite. Each group was divided into 2 sub-groups and then performed immunization of Salmonella flagella with different adjuvants which were Freund's adjuvant and croton oil. The rates of egg-production in all groups were normal range but no difference was found between illite-treated and untreated groups. The serum antibody titers of Freund's adjuvant-used subgroup in illite fed groups were significantly increased, especially from 6-to 9-week after $1^{st}$ immunization compared to those of control groups (p<0.05). And the antibody titers of croton oil-used subgroup in illite-fed groups were also significantly increased, especially at 4-, 6- and 7-week (p<0.05). The results demonstrated that the feeding illite stimulated the immune response against S. typhimurium flagella antigen in laying hens and suggest that the supplementation of illite to the poultry diets may support protective effects against bacterial infections such as Salmonellosis.