• Journal of the Korea Concrete Institute
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• v.15 no.2
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• pp.314-322
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• 2003

Pipe cooling method is widely used for reduction of hydration heat and control of cracking in mass concrete structures. However, in order to effectively apply pipe cooling systems to concrete structures, the coefficient of flow convection relating the thermal transfer between inner stream of pipe and concrete must be estimated. In this study, a device measuring the coefficient of flow convection was developed. Since a variation of thermal distribution caused by pipe cooling has a direct effect on internal forced flows, the developed testing device is based on the internal forced flow concept. Influencing factors on the coefficient of flow convection are mainly flow velocity, pipe diameter and thickness, and pipe material. Using experimental results from the developed device, the coefficient of flow convection was calculated. Finally, a general prediction model was proposed by theoretical procedures. The proposed prediction model is able to estimate the coefficient of flow convection with flow velocity and material properties of pipe. From comparison with experimental results, the coefficient of flow convection by this model was well agreed with those by experimental results.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.666-669
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• 2017

We analyze the problems of the current system, develop and apply the revenue water ratio integration management system for problem solving, and present the analysis of the effect. It will contribute to the improvement of the revenue water ratio through systematic and efficient revenue water ratio management and reduction of the workload of the person in charge through the oil revenue water ratio integration system. It will contribute to the improvement of the revenue water ratio through systematic and efficient revenue water ratio management and reduction of the workload of the person in charge through the revenue water ratio integration system.

• Applied Chemistry for Engineering
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• v.30 no.1
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• pp.39-42
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• 2019

We report on the design of oil-water separators and the selection of materials for the effective application of highly selective membranes fabricated by commercial PET (polyester) fabrics. The waterproof ability of PET fabrics was optimized to improve the separation selectivity. The density of individual PET fabrics should be over $60g/m^2$, and the multi-layered structure is more favorable for the waterproof ability together with maintaining the removal efficiency. For the continuous adsorption and removal process, the rotating perforated cylinder was selected, and covered with membranes. Furthermore, more improved and stable removal efficiency was obtained by installing floating baffles which forces the oil content to move toward membranes.

• Composites Research
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• v.36 no.2
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• pp.69-79
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• 2023

Oil-water separation is a critical process for several industrial applications, including oil production, wastewater treatment, food processing, and environmental area such as marine oil spills. The separation efficiency of oil-water mixtures can be influenced by various factors such as mixture composition, oil and water conditions, and the separation technology used. Over the years, various technologies have been developed to separate water and oil by physical, chemical and biological methods. This paper presents an overview of the various methods and technologies available for oil-water separation, including gravity separation, centrifugal separation, and separation using adsorbents, filters. The strengths and limitations of each method are discussed, along with recent research trends and future prospects. Furthermore, this paper aims to provide direction for future research and industrial application of sustainable and environmentally friendly oil-water separation technologies. In conclusion, we provide a comprehensive overview of recent oil-water separation technologies that will be beneficial to researchers and industrialists in the field of oil-water separation.

• Water for future
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• v.28 no.1
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• pp.153-168
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• 1995

The purpose of this study is to develop an efficient model for the least cost design of multisite detention systems. The IDP (Incremental Dynamic Programming) model for optimal design is composed of two sub-models: hydrologic - hydraulic model and optimization model. The objective function of IDP is the sum of costs; acquisition cost of the land, construction cost of detention basin and pumping system. Model inputs include channel characteristics, hydrologic paramenters, design storm, and cost function. The model is applied to the Jung- Rang Cheon basin in Seoul, a watershed with detention basins in multiple branching channels. The application results show that the detention system can be designed reasonably for various conditions and the model can be applied to multi-site detention system design.

• Journal of the Korean Geophysical Society
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• v.7 no.2
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• pp.151-155
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• 2004

To solve the urban flood problems, it must get the enough channel conveyances and pumping capacities. It needs set up the detention system to control the flow over the channel capacity. Inspite of this detention system, the peak flow may increased by rainfall distribution and the delay of flow. This shows a design model of detention system which can consider the time problems from mutual connections of the detention storages and pumping flow using IDP(Incremental Dynamic Programming) method.

• Applied Chemistry for Engineering
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• v.30 no.2
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• pp.141-144
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• 2019

Oil-water separators are commonly used in the oily wastewater treatment for the reuse of water resources. Recently, various approaches have been conducted to design and manipulate the oil-water separator installed with highly functionalized membranes. Membrane technologies should encompass the selectivity, durability, economics and processability of materials, and effective oil water separators be also developed to exhibit the optimal performance of the materials. In this mini-review, we highlight the large scale fabrication of membrane materials and the effective design of oil water separators.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.11a
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• pp.304-306
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• 2008

일상 생활 및 제반 활동을 유지시키는 중요한 사회 기반 시설은 상수도이다. 이 논문에서는 상수도 관리의 기본이 되는 유량의 계측과 분배, 관리에서 가장 효과적인 것으로 판단이 되는 상수도를 최적으로 관리하는 상수도 유수율 관리 시스템의 설계 및 구현 방법을 제안한다. 이 논문에서 제안하는 상수도 유수율 관리 시스템의 개발은 국민생활의 질향상이라는 시대적 요구를 충족시키고, 양질의 도시문화시설제공 및 수요자에 대한 보다 나은 서비스를 제공할 수 있는 상수도 기반 시설의 설계 방향을 제시할 것으로 판단된다.

• Proceedings of the Korea Information Processing Society Conference
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• 2006.05a
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• pp.589-592
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• 2006

상수도는 도시의 일상생활 및 제반 활동을 유지시키는 중요한 사회기반 시설임에도 불구하고 시설 확대 이외의 종합적 관리 대책이 제시되지 않아 시설 노후화 및 불량으로 인한 낭비 요소가 매우 높다. 이와 같은 문제를 해결하기 위해 이 논문에서는 상수도의 생산에서 각 수용가에서 사용되는 부분에 대한 다양한 성격의 데이터들을 데이터베이스화 하고 이에 대한 분석 및 평가를 통해 무효수량 발생 원인을 쉽게 찾아 신속하게 대응함으로써 적은 노력으로 유수율을 향상시킬 수 있는 소프트웨어 시스템의 개발을 목표로 한다. 이 논문에서 개발한 유수율 제고 시스템은 상수도 시설에 대한 직접 탐사 이전에 누수 및 무효수량 발생 원인을 정량적으로 분석 평가함으로써 적은 비용으로 유수율 향상에 크게 기여할 것으로 기대된다.

• Korean Journal of Soil Science and Fertilizer
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• v.5 no.2
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• pp.43-52
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• 1972

본실험은 유수형성기에 2일간 배수할 때 질소질 비료의 비종(유안과 요소) 및 시용시기(이앙기와 유수형성기)가 수도의 질소이용율에 미치는 영향을 보기 위해서 기후와 토양이 상이한 부산(동아대학교 농과대학 포장)과 서울(방사선 농학연구소 농장, 금곡)에서 농광 및 봉광 두품종을 사용해서 1970년에 실시 되었다. 유수 형성기에 2일간 배수하고 질소질 비료를 시용한 처리는 상시 담수구에 비해서 A-Value에 있어서 유의차가 없었으나 비료의 시용시기나 비종간에는 뚜렸한 차이가 있었다. 유수형성기에 추비하는것이 이앙기에 기비로서 시용하는 것 보다 자실에서 본 비료의 이용율이 4~5배 높았다. 자실의 질소함량은 봉광의 것이 실험지역에 관계없이 농광의 것보다 높았으며, 비료 이용율도 높은 경향을 나타내었다. 부산토양에서의 질소의 A-Value가 품종이나 비종에 관계없이 서울의것 보다 항상 높았던 것은 부산 토양의 질소함량이 높은데 기인하는 것으로 생각된다.