• 한국자동차공학회논문집
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• 제9권6호
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• pp.112-118
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• 2001

In this study the leakage current measurement method based on a porous ceramic is applied to check the conductive substance caused by the ionized particles. By using engine and chassis dynamometer and an experiment vehicle, in which the hydrocarbon sensor (HC sensor) was exposed to the exhaust gas to create the electrical signal, the HC sensor in the exhaust line checked the conductive ions in emission gas. Generally the output electrical signal of HC sensor is followed with amount of hydrocarbon in the experiments in cold start and operation. By combining the electrical signal, a measure of conductivity of exhaust gas with hydrocarbon can be provided by OBD (On Board Diagnosis) II and EMS (Engine Management System).

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.581-586
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• 2009

Knowledge of ground thermal properties is most important for the proper design of large scale BHE(borehole heat exchanger) systems. The type, pipe size and thermal performance of the BHE is highly dependent on the ground source heatpump system-efficiency and instruction cost. Thermal response tests with mobile measurement devices were developed primarily for insitu determination of design data for large diameter BHE for triple-U spacer apply. The main purpose has been to determine insitu values of effective ground thermal conductivity and thermal resistance, including the effect of ground-water flow and natural convection in the boreholes. The test rig is set up on a some trailer, and contains a circulation pump, a inline heater, temperature sensors, flow meter, power analysis meter and a data logger for recording the temperature, fluid flow data. A constant heat power is injected into the borehole through the tripl-U pipes 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 of large diameter BHE for spacer apply.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술대회 논문집 전문대학교육위원
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• pp.34-37
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• 2003

The purpose of this paper is the development of portable body fat meter. Bioelectrical impedance method for measuring human body composition is based upon the principle that the electrical conductivity of the fat mass is far greater than that of the fat. Finally measurement of percent body fat was made possible using a developed impedance measuring device which measure impedance between the thumb and ring finger.

• 한국임상수의학회지
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• 제15권2호
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• pp.242-246
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• 1998

These studies were Performed to provide some basic informations for developing an automatic system in dairy farming in order that the farmers may easily and automatically detect the mastitis. Electrical conductivity of each milk sample was measured by micro-ohm meter and also the number of somatic cell was detected by somecounter. The major microorganisms causing mastitis were also investigated. The rate of infected cattle with mastitis was 33.0% among 2,540 dairy cattle and the rate of infected quarters with mastitis was 13.9 % among 9.660 quarters. When the number of somatic cell was under lost electrical conductivity of the milk was 0.073, whereas number of somatic cell was over $3{\times}10^{6}$, electrical conductivity was increased by 0.167. When electrical conductivity of milk was over 0.073, the cattle was diagnosised as mastitis. The major micmorganisms of mastitis were Staphylococcus spp. (55-60%) and Streptococcus spp. (15-20%).

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.191-192
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• 2020

The purpose of this study is to measure the electrical conductivity of cementitious composites as an early step to obtain shielding performance by mixing various type of steel fiber into cementitious composites, the main building material of protection facility, to shield electromagnetic pulse (EMP) damage. Fiber such as conductors as amorphous metallic fiber, hooked steel fiber, and smooth steel fiber are mixed into cementitious composites to give electrical conductivity and measure the impedance of concrete using LCR meter. By doing this, the electrical conductivity of each type of steel fiber reinforced cementitious composites (FRCC) is compared.

• 보존과학회지
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• 제26권4호
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• pp.397-406
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• 2010

철제유물에서 용출된 수용성 염소이온의 농도를 측정하는 가장 이상적인 방법은 탈염처리 용액을 이온크로마토그래피(Ion Chromatography)로 분석하는 것이지만 대부분의 문화재 관련기관에서는 예산이나 전문인력 부족 등의 이유로 사용하지 못하고 염소이온농도 측정기(Cl meter)를 주로 사용하고 있다. 본 연구는 철제유물의 탈염처리 용액에 대한 염소이온농도 측정기의 $Cl^-$ 이온 농도 측정결과와 이온크로마토그래피의 측정결과를 교차 검증하여 상호 기기간의 신뢰성과 안정성을 평가하고자 한다. 분석결과 초순수는 염소이온농도 측정기의 전극에 잔류하는 수용성 염소이온의 영향으로 미량의 염소이온이 검출되었고, Sodium sesquicarbonate 시약 성분에 미량으로 존재하는 수용성 염소이온이 검출되었다. 탈염처리한 수용액은 탈염 1차에서 가장 많은 염소이온이 측정되었으며, 탈염 2차부터 탈염 4차까지는 소폭 감소하다가 초순수을 이용하는 탈알칼리 단계에서부터 다시 감소하는 경향을 보였다. 염소이온농도 측정기마다 측정횟수에 따른 편차를 보였으며, 탈염용액 내에 염소이온 농도가 높을수록 편차는 심해졌다. 하지만 염소이온 농도가 낮을 경우 편차가 적어 철제유물의 염소이온농도를 측정하기 위한 측정기기로 안정된 결과를 보였다. 전기전도도 측정법은 알칼리 용액의 전기전도도가 높게 나타남에 따라 $Cl^-$ 이온의 함량을 예측하기에는 부적합한 것으로 판단된다.

• 한국전기전자재료학회논문지
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• 제25권6호
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• pp.431-434
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• 2012

In this paper, heat-releasing sheets made of AlN powder and acryl binder as thermoset were prepared using tape casting method. The crystal structure and morphology, the thermal properties as nonvolatile solid content and thermal conductivity, and the surface resistance of heat-releasing sheet were measured by using X-ray diffractometer, field emission-scanning electron microscopy, thermo gravimetric analyzer and laser flash instrument, and surface resistance meter. It was proved that thermal conductivity is greatly affected by the content of binder in heat-releasing sheet. Superior thermal conductivity above 3.5 W/mK and suface resistance were obtained at heat-releasing sheet with above 90% of AlN powder.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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• pp.92-97
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• 2011

Nowdays the most critical problem is global warming and the most important reason is the high emition of carbondioxide. 23% of the use of carbondioxide is used in building and decreasing the use of it is very important. One of the biggest factor that can decrease the use of energy is developing the heat conducting ratio of the materials we use in building. Heat conducting ratio is the important factor in the use of reducing energy comsumation. In this research, there are methods about how to measure the heat conducting ratio, and the existing the representing measuring method which is Heat Flow Meter HFM 436, Laser Flash Analysis and find out about the TCi of the new method C-Therm and compare the results.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권11호
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• pp.477-482
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• 2005

We have investigated volume resistivity and thermal properties showed by changing the content of carbon black which is the component parts of semiconducting shield in underground power transmission cable. Specimens were made of sheet form with the nine of specimens for measurement. Volume resistivity of specimens was measured by volume resistivity meter after 10 minutes in the preheated oven of both 25$\pm$1[$^{\circ}C$] and 90$\pm$1[$^{\circ}C$]. And specific heat (Cp) and thermal conductivity were measured by Nano Flash Diffusivity and DSC (Differential Scanning Calorimetry). The measurement temperature ranges of specific heat using the BSC was from 20[$^{\circ}C$] to 60[$^{\circ}C$], and the heating rate was 1[$^{\circ}C$/min]. And the measurement temperatures of thermal conductivity using Nano Flash Diffusivity were both 25[$^{\circ}C$] and 55[$^{\circ}C$]. Volume resistivity was high according to an increment of the content of carbon black from these experimental results. And specific heat was decreased, while thermal conductivity was increased by an increment of the content of carbon black. And both specific heat and thermal conductivity were increased by heating rate because volume of materials was expanded according to rise in temperature.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.162-167
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• 2006

Nanofluid is a kind of new engineering material consisting of nanoparticles dispersed in base fluid. Nanofluids could have various applications such as magnetic fluids, heat exchanger working fluids, lubricants, drug delivery and so on in present study, various nanoparticles, such as MWCNT (Multi-walled Carbon Nanotube), fullerene, copper oxide, and silicon dioxide are used to produce nanofluids. As base fluids, DI-water, ethylene glycol, oil, and silicon oil are used. To investigate the thermo-physical properties of nanofluids, thermal conductivity and kinematic viscosity are measured. Stability estimation of nanofluid is conducted with UV-vis spectrophoto-meter. In this study, the high pressure homogenizer is the most effective method to produce nanofluid with the prepared nanoparticle and base fluid. Excellently stable nanofluids are produced with the magnetron sputtering system. Thermal conductivity of nanofluid increases with increasing particle volume fraction except water-based fullerene nanofluid which has lower thermal conductivity than base fluid due to its lower thermal conductivity, 0.4 W/mK. The experimental results can't be predicted by Jang and Choi model.