• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.483-487
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• 2006

본 연구는 비점오염원에 의한 수질오염현상을 억제하기 위한 수변지역의 관리기법 중 하나인 식생여과대를 효과적으로 설치하기 위하여 식생에 의한 오염물질의 저감능력을 파악하고 효율적 설치방안을 모색하기 위하여 수행되었다. 연구결과 T-N과 T-P의 깊이별 오염물질 저감효과는 나대지에서 표면유출이 각각 17.6%, -23.9%, 단면유출이 각각 51.7%, 91.0%, 하부유출이 각각 38.4%, 89.3%인 것으로 나타나 표면층을 통한 유출보다는 토양층에 침투될수록 오염물질의 저감효과가 높아지는 것으로 나타났다. 잔디로 표면층을 식재한 실험에서는 표면, 단면, 하부유출에서의 T-N이 각각 16.0%, 57.1%, 38.4%의 오염물질 저감효과를 보였고, T-P의 저감효과는 각각 -9.7%, 83.6%, 88.8%인 것으로 조사되었다. 또한 돌미나리로 표면층을 식재한 실험에서는 표면, 단면, 하부유출에서의 T-N 처리효율이 각각 -2.6%, 62.1%, 71.2%로 나타났으며, T-P는 각각 -7.2%, 94.5%, 84.5%인 것으로 조사되었다. 결론적으로 식생을 한 경우 전체적으로 오염물질의 저감효율이 비교적 안정되게 유지되는 것으로 나타났으나, T-P의 표면층을 제외하면 전체적인 저감효과에 크게 영향을 미치지 않은 것으로 판단된다. 그러나 일반적으로 알려져 있는 식생에 따른 오염물 저감효과에 대한 순기능 즉 토양입자의 침식방지, 토양용액의 저류작용 및 공극확대에 따른 침투능력 증대, 토성의 개량 등과 같은 기능을 무시할 수 없으므로 오염저감효과를 극대화하기 위해서는 처리대상이 되는 하천유역의 자생적 식생을 보다 효과적으로 활용할 수 있는 방안마련이 비용적 측면이나 생태 보존적 측면에서 유리할 것으로 판단된다.one)을 설치하는 대책이 필요하다. 저수지 관리를 효과적으로 수행하기 위해서는 저수지 내부의 탁도 거동을 정확히 예측할 수 있어야 한다. 따라서 추후 동수역학 및 열역학에 기초한 3차원 수치모형 연구와 성층흐름에 정밀한 밀도류 실험연구 및 이에 대한 적용이 필요할 것으로 판단된다.함으로써 정보의 질적보장과 정보전환의 표준화방안을 제시하는 정보분석시스템이다.이용, 수자원의 지속적 확보기술의 특성에 따른 4개의 평가기준과 26개의 평가속성으로 이루어진 2단계 기술가치평가 모형을 구축하였으며 2개의 개별기술에 대한 시범적용을 실행하였다.하는 것으로 추정되었다.면으로의 월류량을 산정하고 유입된 지표유량에 대해서 배수시스템에서의 흐름해석을 수행하였다. 그리고, 침수해석을 위해서는 2차원 침수해석을 위한 DEM기반 침수해석모형을 개발하였고, 건물의 영향을 고려할 수 있도록 구성하였다. 본 연구결과 지표류 유출 해석의 물리적 특성을 잘 반영하며, 도시지역의 복잡한 배수시스템 해석모형과 지표범람 모형을 통합한 모형 개발로 인해 더욱 정교한 도시지역에서의 홍수 범람 해석을 실시할 수 있을 것으로 판단된다. 본 모형의 개발로 침수상황의 시간별 진행과정을 분석함으로써 도시홍수에 대한 침수위험 지점 파악 및 주민대피지도 구축 등에 활용될 수 있을 것으로 판단된다. 있을 것으로 판단되었다.4일간의 기상변화가 자발성 기흉 발생에 영향을 미친다고 추론할 수 있었다. 향후 본 연구에서 추론된 기상변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기 위한 연구가 필요할 것이다.게 이루어질 수 있을 것으로 기대된다.는 초과수익률이 상승하지만, 이후로는 감소하므로, 반전거래전략을 활용하는 경우 주식투자기간은 24개월이하의 중단기가 적합함을 발견하였

• Journal of Korea Port Economic Association
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• v.29 no.4
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• pp.157-174
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• 2013

A shipbroking is maritime service business, which is consist of market of freight, shipbuilding, sales & purchase and demolition for intermediation between customer and supplier. In this way, a shipbroking business has strong relationship with shipping industry and is also knowledge service business for creation additional value based on shipping, shipbuilding, financial and law etc. However, the research on the evaluation items and a method for shipbroking company were not carried out in previous research. In this paper, We defined evaluation items with three high level, six middle level and sixteen low level for evaluation of shipbroking service by expert's brainstorming and AHP(analytic hierarchy process) method. And also carried out survey to employees of shipbroking company as supplier and shipping company as customer. As a result of survey, result of service in high level, convenient of middle level and credibility of low level are evaluated highly, and also business credit rating, profit of customer, achievement of customer's object are considered to more important than others items. In case of comparison between group, a method of contact with client, problem-solving ability, good relationship with clients of international and domestic evaluated importantly in common.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.6
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• pp.2833-2845
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• 2012

In this study, the amount of waste resource that could be recovered was analyzed. The installation and operation costs of waste resource recovery for both single- and multi-regional facility were calculated, and compared with the costs of landfill to investigate the feasibility of them. RDF(Refuse Derived Fuel) process and resource recovery by incineration process were considered as waste resource recovery facility. And, the multi-regions for cost analysis were established on the basis of the proper generation rate of municipal waste with the consideration of combustible ratio. The study results showed that single region facility for both RDF and incineration process has no economic benefit, compared with the landfill method. For the multi-regional facility, RDF process could save a large cost than the landfill method, but the incineration facility couldn't. Separate from the economic benefits, the waste resource recovery should be importantly considered when considering the depletion of fossil fuel, global warming, environmental toxicity, and the enormous expenses due to social conflict and confuse. When the CDM(Clean Development Mechanism) is vitalized in the near future, the additional economic benefits by CERs(Certified Emission Reductions) could be expected. CERs for RDF facility is corresponding to about 256.5 billion won, and CERs for incineration facility is corresponding to about 54 and 77.4 billion won for single- and multi-regional facility, respectively.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.6
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• pp.772-779
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• 2019

The subsea pipeline has received considerable attention as a high-value-added industry linked to the energy and steel industries including natural resource development. The design and installation of the subsea pipeline require a variety of key technologies to carry out the project. In particular, a thorough pre-verification process through pre-commissioning is essential for the safe operation of the subsea pipeline. The hydrotesting stage in the pre-commissioning process of the subsea pipeline is known to be affected significantly by the ambient temperature change; however, there is a little study based on the theoretical and numerical approach. In this study, the method of predicting the internal temperature change using the transient heat transfer method for the stage of hydrotesting during the pre-commissioning process of the subsea pipeline and the prediction method of the pressure variation in the pipeline using it were proposed. The predicted results were compared with field test results and its effectiveness was verified. The proposed analysis procedure is expected to contribute to the productivity improvement of the subsea pipeline installation project by enabling the prediction of pressure variation through pipeline heat transfer simulation from the initial design stage of the subsea pipeline installation project.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.2
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• pp.92-104
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• 2017

Previous management for speed in road traffic system was aimed only to the improvement of mobility and safety. However, consideration for the aspect of environment and energy consumption efficiency was valued less than the former ones. Nevertheless, economical damage scope caused by climate change has been increasing and it is estimated that environmental value will be increased because of the change of external circumstances. In addition, policy for reducing carbon emission in transportation system was assessed as insufficient in improving the condition of traffic road since it only focused on the transition of private vehicle into public transportation and development of eco-friendly car. Now it is the time to prepare for the adaptation strategy and precaution for the increased number of private vehicle in Korea. For this, paradigm shift in traffic operation which includes the policy not only about the mobility but also about caring environment would be needed. It is needed to be able to monitor the actual amount of greenhouse gas in real time to reduce the amount of emitted greenhouse gas in the aspect of traffic management. In this research, a methodology which can build on-line greenhouse gas emission monitoring system by using real time traffic data and predicting the circumstance in next 5 minutes was suggested.

• Journal of the Korea Concrete Institute
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• v.28 no.3
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• pp.329-340
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• 2016

Increase in demotion and repair works on buildings in the construction market generates a large amount of construction waste. Recycling of construction waste is important for saving of resources, preservation of environment and constant advance of the construction industry. Accordingly, the environmental and economic value of recycled aggregate, which is produced after waste concrete is crushed, is increasingly highlighted. It is generally known that compared to concrete made of ordinary aggregate, concrete made of recycled aggregate has low quality, and the low quality is dependent on the amount of the bonding heterogeneous (cement paste and mortar) as well as the amount of the pores within the bonding heterogeneous. Reports on carbonation mechanism shows that the pores of cement-based materials are filled up by the progress of carbonation. Therefore, this study aims at an estimation of the period for optimum carbonation reforming appropriate for the thickness of the bonding heterogeneous of recycled aggregate, based on carbonation mechanism, with a view to improving the product quality by means of filling up the pores of the bonding heterogeneous of recycled aggregate. This study drew the carbonation depth according to the passage of age by calculating the bonding ratio and bonding thickness of the bonding heterogeneous as against the particle size distribution of recycled aggregate as well as by chemical quantitative analysis according to the age of accelerated carbonation of mock-up samples imitating bonding heterogeneous. Based on the correlation between the age of accelerated carbonation and carbonation depth, this study also proposed the estimated period of carbonation reforming of recycled aggregate appropriate for the thickness of the bonding heterogeneous.

• Journal of Korean Society for Geospatial Information Science
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• v.10 no.4 s.22
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• pp.85-93
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• 2002

Since the National Geographic Information System(NGIS) project of 1995, the geographic information projects have been promoted in various areas such as central and local governments. In the fact that large scale budget has been invested to geographic information projects as a national policy, the cost-benefit analysis would be essential to enhance the efficiency of the resource allocation. In this circumstance, this study analyzes the costs and benefits of geographic information produced by NGI(National Geography Institute). As a result of the cost-benefit analysis, the total amount of benefits were estimated approximately 620 million dollars and the accumulated ratio of the cost to benefit was 1 to 4.4. Also, the internal ratio of the benefit was 38%, which justified the large scale investment. In case of adding qualitative benefits which can not be measured in a quantitative term, the overall benefits from using such geographic information would be much higher than quantitative benefits. Further research work is required for more objective verification of the large scale national project such as building nationwide geographic information.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.510-516
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• 2003

연안관리 정책을 결정하기 위해서는 다양한 정보의 수집과 이를 체계적으로 관리하고 분석할 수 있는 기법이 필요하다. 특히, 다양한 이해집단과 목적들이 상충하는 지역의 특성을 파악하기 위해서는 환경, 사회, 경제적인 기준 및 의사결정자의 가치체계가 반영될 수 있어야 하며, 선호도가 반영된 요소를 효율적으로 분석할 수 있어야 한다. 이에, 본 연구에서는 공간자료의 처리 및 분석이 용이한 GIS 환경에 다기준 분석법, 그 중에서도 AHP 모형을 결합하는 방법을 다루어 보았다. 분석과정을 살펴보면, 본 연구에서는 지역에 영향을 미치는 사회ㆍ경제적인 지표, 환경 지표를 정하였고, 이런 지표들의 데이터를 GIS라는 도구를 통하여 분석이 용이하도록 변환시켰다. 한편, 이 지역에 영향을 미치는 각 기준들의 중요성을 파악하여 의사결정자의 의견을 반영할 수 있도록 다기준 분석법의 하나인 AHP를 이용하여 가중치를 산정하였다. 다음으로, 다양한 출처의 자료를 표준화하여 GIS의 래스터 자료로 구축한 후, 가중치를 적용한 개별 레이어를 지도대수와 중첩분석을 이용하여 최종 결과 레이어를 생성하였다. 생성된 최종 결과 레이어 상의 공간의 대안인 각 셀 값을 비교ㆍ분석하였다. 이로 인한 결과는 연안의 유한한 자원과 공간의 다양한 이용상태를 관리하기 위한 해안과 육상의 정보를 제공할 수 있다. GIS와 다기준 분석을 통합함으로써 다양한 출처의 공간정보를 분석하고 연안의 현 상태를 밝힐 수 있다. 또한, 이것은 분석 결과가 단순하고 명확하게 설명되어 정책 결정자에게 유용한 정보를 제공할 뿐만 아니라, 이 정보를 이용하여 실질적인 연안관리계획을 수립하는데 도움이 된다.가능성 0.5이상의 면적은 59%를 차지하였다.퇴적이 우세한 것으로 관측되었다.보체계의 구축사업의 시각이 행정정보화, 생활정보화, 산업정보화 등 다양한 분야와 결합하여 보다 큰 시너지 효과와 사용자 중심의 서비스 개선을 창출할 수 있는 기반을 제공할 것을 기대해 본다.. 이상의 결과를 종합해볼 때, ${\beta}$-glucan은 고용량일 때 직접적으로 또는 $IFN-{\gamma}$ 존재시에는 저용량에서도 복강 큰 포식세로를 활성화시킬 뿐 아니라, 탐식효율도 높임으로써 면역기능을 증진 시키는 것으로 나타났고, 그 효과는 crude ${\beta}$-glucan의 추출조건에 따라 달라지는 것을 알 수 있었다.eveloped. Design concepts and control methods of a new crane will be introduced in this paper.and momentum balance was applied to the fluid field of bundle. while the movement of′ individual material was taken into account. The constitutive model relating the surface force and the deformation of bundle was introduced by considering a representative prodedure that stands for the bundle movement. Then a fundamental equations system could be sim

• Journal of Energy Engineering
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• v.25 no.4
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• pp.141-151
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• 2016

Recently, technology for energy recovery from waste has been increasing interest globally including the Korea. In Korea, we have interested in using biogas generated from the sewage treatment process. As one alternative, there are operating biogas combined heat and power plant. The generation amount of the Sewage Sludge are expected to grow in the future. For this reason, total processing cost of Sewage Sludge will increase. To solve this problem, it seems will be invested with the expansion of facilities that use biogas as energy. Therefore, quantitative information on such facilities is required. Thus, this study attempts to economic feasibility analysis for Seonam Biogas Combined Heat and Power Plant. Meanwhile, as the benefit items for economic feasibility analysis consider electricity supply benefit except for heat supply benefit. The average prices of electricity use were residence 123.69, commercial 130.46, and industry 102.59 won per kWh for the year 2015, In addition, the economic benefit are calculated to be residence 310.21, commercial 378.49, and industry 222.87 won per kWh. The results of economic feasibility analysis is NPV 72.18 billion won, B/C 1.90, IRR 37%, shows that economic validity of Seonam Biogas Combined Heat and Power Plant.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.5
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• pp.629-636
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• 1996

The developments of mariculture fisheries depend on both the natural environmental inputs such as sun, rain, wind, tide and the economic inputs such as ships, fuels, facilities, labor. for the enhancement of mariculture productivity in Deukryang Bay, a new attempt has been made to connect the environmental resources and the economic activity within one system. This study applies EMERGY analysis that evaluates environmental energies, fuels, goods and services in terms of solar emjoelus. In total EMERGY use $(69.65\times10^{20}\;sej/yr)$ the natural environment inputs is $78\%\;(54.60\times10^{20}\;sej/yr)$. This means that the mariculture in Deukryang Bay depends on mainly environmental resources. Net EMERGY yield ratio was 4.63 which indicated high value as a resource, EMERGY investment ratio was 0.28 that means to gain 3.6 times energy from the natural environment than those of economy. If the fisherie's products are made by renewable EMERGY input to Deukryang Bay, the calculated carrying capacity of fishes, crustaceans, shellfish and seaweeds were 1,140, 110, 1,553 and 9,074 ton/yr, respectively. If the quantity of renewable EMERGY input to mariculture grounds in Deukrysng Bay was calculated-based on only shellfish product, shellfish products was estimated as about 1,195 ton/yr.