• 한국환경과학회지
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• 제13권7호
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• pp.697-701
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• 2004

Most of methane gas result from waste matter in landfill, therefore the persons concerned take an increasing interest in management of gases in landfill. Infrared Gas Analyzer was used to measure components of gases, $CH_4,$ $CO_2,$ $O_2,$ through gas exhausted pipe. To measure amount of the gas flow meter(Portable Hot-Line Current Meter) was used and it was set at right angles with direction of the flow. In this research the total amount of methane gas produced in Beck-Suk Landfill was calculated through FOD method suggested by IPCC. This research found that in Chon-An Beck-Suk Landfill anaerobic resolution was made actively and the amount of methane gas produced there was 54.14%, which is higher than common figure, 50%, in other researches. The components of reclaimed waste matter, especially, organic waste matter can have a great effect of the amount of the greenhouse gases produced in landfill. We can expect that the amount of greenhouse gas will decrease from 2005, when it will be prohibited from carrying kitchen refuse and sludge into landfill.

• 조명전기설비학회논문지
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• 제22권4호
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• pp.61-67
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• 2008

본 논문은 발전소 보일러 및 제철소 고로의 미분탄 연소방식에 적용이 가능한 유량계 개발에 관한 연구로, 정전 용량을 이용한 미분탄 유량계를 개발하였다. 먼저 관에 흐르는 미분탄의 밀도 측정이 가능한 센서 및 회로를 설계하였고, 측정된 데이터를 분석하고 밀도를 계산하는 알고리즘을 구현하였다. 압송시스템에 설치된 로드셀의 출력 데이터와 측정된 데이터를 비교하여 개발된 유량계의 신뢰성을 확인하였다.

• 대한기계학회논문집B
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• 제30권8호
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• pp.764-771
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• 2006

Knowledge of ground thermal properties is most important for the proper design of large BHE(borehole heat exchanger) systems. Thermal response tests with mobile measurement devices were first introduced in Sweden and USA in 1995. Thermal response tests have so far been used primarily for in insitu determination of design data for BHE systems, but also for evaluation of grout material, heat exchanger types and ground water effects. The main purpose has been to determine insitu values of effective ground thermal conductivity, including the effect of ground-water flow and natural convection in the boreholes. Test rig is set up on a small trailer, and contains a circulation pump, a heater, temperature sensors and a data logger for recording the temperature data. A constant heat power is injected into the borehole through the pipe system of test rig and the resulting temperature change in the borehole is recorded. The recorded temperature data are analysed with a line-source model, which gives the effective insitu values of rock thermal conductivity and borehole thermal resistance.

• 한국산학기술학회논문지
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• 제13권6호
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• pp.2757-2762
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• 2012

하수관거는 중요한 사회간접시설중의 하나이다. 이러한 하수관거의 파손은 주로 하수관거의 시공에 이용되는 뒤채움재의 부적절한 품질관리 및 다짐관리로 인하여 발생한다. 특히, 원형관로의 경우 현장에서 다짐작업이 어려워 다짐기준을 만족시키기 어렵다. 이러한 문제를 해결하기 위하여 본 연구는 플라스틱 현장조립식 경량기초를 개발하였다. 개발된 경량기초의 하중재하시험 및 변형특성을 평가하였다. 제한된 실험결과로부터 현장조립식 플라스틱 경량기초의 사용은 뒤채움재의 다짐관리시 발생하는 어려움을 줄여줄 수 있는 대안으로 사용 가능함을 확인하였다.

• 한국안전학회지
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• 제25권1호
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• pp.32-37
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• 2010

When back-out & firing Process applies heat, hume is piled up in exhaust duct by organic compound and it have high dangerousness. There by, the process is happening a lot of damage that is exhaust duct fire. However we do not have certain fire dangerousness estimation and digestion countermeasure. So we need preventive measure. Back-out & firing is a process which has fine structure, electrical and mechanical characteristics, such as firing kiln and back-out kiln which has pipe line and box type. The box oven is made of heating coil, fan motor and control panel. Back-out & firing process has air circulation institution of quick ventilation type. When we operate this process for long time, fire can break out easily. Duct is made by zinc shredder. If fire breaks out in duct inside, fire by deposit fume can be dispersed easily. Accordinglym, This project estimate danger for back-out & firing process exhaust duct through real fire test. And there is purpose of study to establish preventive measure.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 반도체재료
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• pp.34-37
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• 2001

As the integrated circuit device shrinks to smaller dimensions, chemical mechanical polishing (CMP) process was required for the global planarization of inter-metal dielectric (IMD) layer with free-defect. However, as the inter-metal dielectrics (IMD) layer gets thinner, micro-scratches are becoming as major defects. Micro-scratches are generated by agglomerated slurry, solidified and attached slurry in pipe line of slurry supply system. To prevent agglomerated slurry particle from inflow, we installed 0.5${\mu}m$ POU (point of use) filter, which is depth-type filter and has 80% filtering efficiency for the $1.0{\mu}m$ size particle. In this paper, we studied the relationship between defect generation and pad count to understand the exact efficiency of the slurry filtration, and to find out the appropriate pad usage. Our preliminary results showed that it is impossible to prevent defect-causing particles perfectly through the depth-type filter. Thus, we suggest that it is necessary to optimize the flow rate of slurry to overcome depth type filters weak-point, and to install the high spray of de-ionized Water (DIW) with high pressure.

• 상하수도학회지
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• 제31권6호
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• pp.511-519
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• 2017

Multi-regional water supply system, which installed for supplying multiple water demands, is characterized by large-sized, long-distance, tree-type layout. This system is vulnerable to long-standing service interruption when a pipe breaks is occurred. In this study, a numerical method is proposed to calculate drainage time that directly affects time of service interruption. To begin with, governing equations are formulated to embed the delayed drainage effect by the friction loss, and to resolve complicated connection of pipelines, which are derived from the continuity and energy equations. The nonlinear hydraulic equations are solved by using explicit time integration method and the Newton-Raphson method. The developed model is verified by comparing the result with analytical solution. Furthermore, the model's applicability is validated by the examples of pipelines in serial, in parallel, and complex layout. Finally, the model is utilized to suggest an appropriate actions to reduce the deviation of draining time in the C transmission line of the B multi-regional water supply system.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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• pp.146-150
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• 1998

현재 세계적인 토양환경복원의 추세는 단기간의 높은 처리효율을 기대하는 장치위주의 복원기술적용에서 좀 더 처리시간은 걸리나 저비용의 효율적인 처리기술선택으로 옮겨가고 있다. 이는 지금까지 무리한 투자에서 발생한 부작용을 최소화하기 위해서 취해지고 있는 변화로 식물을 이용한 환경복원기술(phytoremediation)은 이러한 변화에 가장 잘 부응하는 발전 가능성이 매우 높은 미래 복원기술 가운데 하나이다. 이에 본 연구에서는 phytoremediation을 이용하여 디젤로 오염된 토양을 복원하고자 하였다. 먼저 대상오염물에 대한 정화능을 나타내는 식물을 선별하기 위해 알팔파, 옥수수, 피, 물피의 오염농도별 생장 률을 살핀 결과 알팔파가 오염농도에 따른 성장저해를 가장 덜 받는 것으로 나타났다. 이에 알팔파의 발아 test를 거친 후 실제상황을 모사하기 위한 column test를 실시하여 디젤의 제거효율을 살펴보았다. 1)외부로부터 pipe line을 따라 공기를 주입하여 산소를 보충한 처리구와 2)알팔파를 심은 처리구, 3)알팔파와 공기를 넣어준 처리구를 설계하여 디젤의 제거과정을 알아본 결과 제거효과가 가장 높은 처리구는 공기와 알팔파를 함께 넣어준 처리구였다. 이를 통해 유류로 오염된 토양에서 산소가 미생물활동에 커다란 제한요인이라는 것과 공정에 공기주입구를 장착함으로써 식물만으로 처리할 때 대두되는 시간적 제약의 문제를 다소 경감시킬 수 있음이 밝혀져 앞으로 이의 활용가능성이 주목된다.

• 한국환경과학회지
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• 제25권6호
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• pp.829-837
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• 2016

The mechanism of micro-bubble generation with a pump is not clarified yet, so the design of water treatment systems with a micro-bubble generating pump is based on trial and error methods. This study tried to explain clearly quantitative relationships of experimental micro-bubble concentration ($C_{air}$) of continuous operation tests with a micro-bubble generating pump and theoretical air solubility. Operation parameters for the tests were discharge pressure ($P_g$), water ($Q_{w0}$) and air ($q_0$) flow rates, orifice diameter ($D_o$), and retention time (t). The experimental micro-bubble concentrations ($C_{air}$) at 4.8 atm of discharge pressure ($P_g$) were in the range of 21.04 to 25.29 mL/L. When the retention time (t) by changing the pipe line length ($L_p$) increased from 1.22 to 6.77s, the experimental micro-bubble concentrations ($C_{air}$) increased from 25.86 to 30.78 mL air/L water linearly. The dissolved and dispersed micro-bubble concentrations ($C_{air}$) are approximately 4 times more than the theoretical air solubility.

• 한국유체기계학회 논문집
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• 제12권5호
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• pp.7-12
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• 2009

A nuclear fuel test loop(after below, FTL) is installed in the IRI of an irradiation hole in HANARO for testing the neutron irradiation characteristics and thermo hydraulic characteristics of a fuel loaded in a light water power reactor or a heavy water power reactor. There is an in-pile section(IPS) and an out-pile section(OPS) in this test loop. When HANARO is operated normally, the fuel loaded into the IPS has a nuclear reaction heat generated by a neutron irradiation. To remove the generated heat and to maintain the operation conditions of the test fuel, a main cooling water system(MCWS) is installed in the OPS of the FTL. The MCWS is composed of a main cooler, a pressurizer, two circulation pumps, a main heater, an interconnection pipe line and instruments. The interconnection pipeline is a closed loop which is connected to an inlet and an outlet of the IPS respectively. The MCWS is under a cold function test during a start-up period. This paper describes the system flow network analysis results of the flow control of a main cooling water system in the HANARO fuel test loop. It was confirmed through the results that the flow was met the system design requirements.