• 산업경영시스템학회지
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• 제46권3호
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• pp.259-267
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• 2023

At a time when the demand for drones is increasing, a plan to utilize drone images was sought for efficient promotion of cadastral resurvey. To achieve the purpose of this study, the technical and legal status of drone images was reviewed, and through this, the possibility of using it for cadastral resurvey was primarily reviewed. subsequently, an experiment was conducted targeting the project district to examine whether drone images were applied to boundary extraction, which is the primary process of cadastral resurvey. As a result of the experiment, it was found that boundary extraction from images is possible. However, in some cases, it is impossible due to field conditions or image quality. Therefore, it is necessary first to apply cases where boundary extraction is possible to cadastral resurvey and seek solutions for some impossible cases. In particular, the image quality problem may have problems with the current technology, but it will also have problems with the existing drone equipment. So, standard for drone calibration should also be established. Finally, the cadastral resurvey surveying procedure using drones was also presented

• 대한환경공학회지
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• 제28권11호
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• pp.1148-1153
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• 2006

이온 선택성 미소전극과 전위계를 이용하여 생물막내 이온 농도 측정을 위한 신호 계측 시스템을 구성하였다. 제작된 신호 계측 시스템의 성능과 적용성을 평가하기 위하여 보정곡선의 기울기, 검출한계, 시간경과에 따른 응답신호의 변화, 전위차 선택계수를 조사하였다. 보정곡선의 기울기는 목적이온 농도에 밀접한 비례관계를 나타내었다. 신호 계측 시스템은 $10{\mu}M$ 이하의 낮은 검출한계를 가졌으며, 실험에 사용된 방해이온에 민감하지 않았다. 본 연구에서 제작된 전위계는 상용되는 전위계와의 성능을 비교하였을 때 보정곡선 기울기, 검출한계, 응답시간에서 비슷한 경향을 나타내었다. 본 연구에서 제작된 신호 계측 시스템은 생물막내 이온농토 측정 연구를 위한 경제적이며 신뢰성 있는 시스템으로 사용될 수 있을 것이다.

• 대한원격탐사학회지
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• 제15권4호
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• pp.289-295
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• 1999

Space Physics Sensor (SPS) on-board the KOMPSAT-1 consists of the High Energy Particle Detector (HEPD) and the Ionospheric Measurement Sensor (IMS). The HEPD is to characterize the low altitude high energy particle environment and the effects on the microelectronics due to these high energy particles. It is composed of four sensors: Proton and Electron Spectrometer(PES), Linear Energy Transfer Spectrometer (LET), Total Dose Monitor (TDM), and Single Event Monitor (SEM). 35 MeV proton beam from the medical KCCH cyclotron, at Korea Cancer Center Hospital in Seoul, is used to calibrate the PES. Primary proton beam of 35MeV scattered by polypropylene target is converted to various energy protons according to the elastic collision kinematics. In this calibration, the threshold level of the proton in the PES can be determined and the energy ranges of PES channels are also calibrated.

• 대한교통학회지
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• 제33권4호
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• pp.393-404
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• 2015

기존의 중력모형은 통행비용 변수만으로 존 간 특성을 설명하기 때문에 많은 한계점을 갖게 된다. 현대 도시의 통행 패턴은 거리나 비용뿐만이 아니라 존 별 특성과 교통인프라 수준 등의 영향을 받기 때문이다. 따라서 장래 통행을 합리적으로 추정하기 위해서는 이러한 특성을 고려한 모형이 개발되어야 한다. 본 연구는 이러한 관점에서 접근성 변수를 중력모형의 설명 변수로 도입하였다. 이와 함께 변수가 추가에 따른 2단계 정산기법을 제안하였다. 이는 통행저항함수의 계수를 회귀분석을 통해 우선 추정한 뒤, 존별 균형인자를 순차적으로 추정하는 방법이다. RMSE, E-norm, C.R을 활용한 접근성을 도입한 중력모형의 검증 결과, 기존의 중력모형보다 통행패턴의 구현 능력이 향상된 점을 확인하였다. 특히, 단거리 통행량 추정에 어려움을 겪은 기존 모형의 한계점을 해결하였다는 점이 주목할 만 하다. 결론적으로 본 연구는 새로운 중력모형의 정산기법을 제안함과 동시에 접근성 변수의 도입을 통해 존 간 특성을 구현하였다는 점에서 통행분포모형의 개선 가능성을 제시하였다.

• 대한기계학회논문집B
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• 제29권9호
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• pp.1022-1031
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• 2005

Temporal behavior of the laser induced incandescence (LII) signal is often used for soot particle sizing, which is possible because the cooling behavior of a laser heated particle is dependent on the particle size. In present study, LII signals of soot particles are modeled using two non-linear coupled differential equations deduced from the energy- and mass-balance of the process. The objective of this study is to obtain an appropriate calibration curve for determining primary particle size by comparing the gated signal ratio and double-exponential curve fitting methods. Not only the effects of laser fluence and gas temperature on the cooling behavior but also heat transfer mechanisms of heated soot particle have been investigated. The second-order exponential curve fitting showed better agreements with the LII signals than the gated signal ratio method which was based on the lust-order exponential curve fit. And the temporal decay rate of the LII signal and primary particle size showed nearly linear relationship, which was little dependent on the laser fluence. And it also could be reconfirmed that vaporization was dominant process of heat loss during first loons after laser pulse, then heat conduction played most important role while thermal radiation had little influence all the time.

• 한국대기환경학회지
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• 제32권3호
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• pp.320-328
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• 2016

Among biogenic volatile organic compounds (BVOCs) in the natural ecosystem, monoterpenes, along with isoprene, play important roles in atmospheric chemistry and make significant impacts on air pollution and climate change, especially due to their contribution to secondary organic aerosol production and photochemical ozone formation. It is essential to measure monoterpene concentrations accurately for understanding their oxidation processes, emission processes and estimation, and interactions between biosphere and atmosphere. Thus, traceable calibration standards are crucial for the accurate measurement of monoterpenes at ambient levels. However, there are limited information about developing calibrations standards for monoterpenes in pressured cylinders. This study describes about developing primary standard gas mixtures (PSMs) for monoterpenes at about 2 nmol/mol, near ambient levels. The micro-gravimetric method was applied to prepare monoterpene (${\alpha}$-pinene, 3-carene, R-(+)-limonene, 1,8-cineole) PSMs at $10{\mu}mol/mol$ and then the PSMs were further diluted to 2 nmol/mol level. To select an optimal cylinder for the development of monoterpene PSMs, three different kinds of cylinders were used for the preparation and were evaluated for uncertainty sources including long-term stability. Results showed that aluminum cylinders with a special internal surface treatment (Experis) had little adsorption loss on the cylinder internal surface and good long-term stability compared to two other cylinder types with no treatment and a special treatment (Aculife). Results from uncertainty estimation suggested that monoterpene PSMs can be prepared in pressured cylinders with a special treatment (Experis) at 2 nmol/mol level with an uncertainty of less than 4%.

• 한국지반환경공학회 논문집
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• 제22권3호
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• pp.15-29
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• 2021

본 연구는 낙동강 하구역에 대한 생태계 변동을 예측할 수 있는 생태계 모델을 구축하고 이 모델을 이용하여 총일차생산량과 호흡량을 산정하고자 하였다. 생태계 모델을 AQUATOX 모델을 사용하여 구축하였고 측정된 자료를 이용하여 모델의 검량과 검증을 하였다. 모델의 검량은 낙동강 하구역에서 측정된 클로로필-a 자료를 사용하였고, DO, TN, TP 자료를 이용하여 모델 검증을 수행하였다. 총일차생산량과 호흡량은 계절에 따라 큰 차이를 보이는 것이 일반적이나 낙동강 하구역의 총일차생산량과 호흡량은 하굿둑 방류수의 양에 크게 영향을 받았다. 방류수의 양이 증가할 때는 하구역에 서식하는 식물성 플랑크톤의 유실로 인해 광합성을 할 수 없어 총일차생산량은 0에 수렴하였고, 반면 방류수에 포함된 유기물질의 유입으로 인해 호흡량이 급격히 증가하였다. 유입수량의 증가는 유입수에 포함된 유기물질의 유입을 의미하며, 이 유기물질은 산화작용에 의해 분해되면서 용존산소를 감소시켰다. 다른 나라의 하구역과 비교 시 낙동강 하구역은 총일차생산량이 가장 적은 것으로 나타났고 호흡량이 총일차생산량보다 크기 때문에 유기물의 산화작용에 의해 용존산소를 고갈시키는 상태인 것으로 확인되었다.

• 분석과학
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• 제8권4호
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• pp.427-434
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• 1995

Inductively coupled plasma mass spectrometry combined with the isotope dilution method is used for the determination of lithium. The isotope dilution method is based on the addition of a known amount of enriched isotope (spike) to a sample. The analyte concentration is obtained by measuring the altered isotope ratio. The spike solution is calibrated through so called reverse isotope dilution with a primary standard. The spike calibration is an important step to minimize error in the determined concentration. It has been found essential to add spike to a sample and the primary standard so that the two isotope ratios should be as dose as possible. Since lithium is neither corrosive nor toxic, lithium is used as a chemical tracer in the nuclear power plants to measure feedwater flow rate. 99.9% $^7Li$ was injected into a feedwater line of an experimental system and sample were taken downstream to be spiked with 95% $^6Li$ for the isotope dilution measurements. Effects of uncertainties in the spike enrichment and isotope ratio measurement error at various spike-to-sample ratios are presented together with the flow rate measurement results in comparison with a vortex flow meter.

• 전기학회논문지P
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• 제57권2호
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• pp.164-169
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• 2008

National standard system for calibrating voltage transformer(VT) up to primary voltage of 240 kV have been established in 2005. The system consists of voltage source, regulating unit, VT testing unit, standard VT, VT under test and VT burden. To verify and validate the performance for 240 kV VT calibration system, the comparison with the National Measurement Institute of Australia(NMIA) has been performed using same VTs. The comparison results of the VTs mesured at the Korea Research Institute of Stansdards and Science(KRISS) are consistent with those measured at NMIA within 0.002 % for ratio error and 0.14 min for phase displacement in the primary voltage ranges of Vp = 3300 V - 22000 V with a secondary voltage of Vs = 110 V.

• 한국대기환경학회지
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• 제34권2호
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• pp.331-341
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• 2018

Hazardous air pollutants(HAPs) in the atmosphere are regulated as major air pollutants in Korea by the Air Pollution Control Act. In order to manage and control HAPs, accurate standards, which are traceable to the International System of Units(SI), are required. In this study, primary standard gas mixtures(PSMs) of volatile organic compounds(VOCs) which are specified as HAPs were developed at $1{\mu}mol/mol$ levels. The selected fourteen VOCs include Benzene, Toluene, Ethylbenzene, m-Xylene, Styrene, o-Xylene, Chloroform, 1,1,2-Trichloroethane, Trichloroethylene, Tetrachloroethylene, 1,1-Dichloroethane, Carbon tetrachloride, 1,3-Butadiene, and Dichloromethane. The HAPs PSMs were gravimetrically prepared in aluminum cylinders and their consistency was verified within the relative expanded uncertainty of 0.71% (k=2). Potential adsorption loss onto the internal surface of cylinders was estimated by cylinder-to-cylinder division method. No adsorption loss was observed within the uncerainty of 0.53%. The long-term stability of the HAPs PSMs was evaluated comparing with freshly prepared HAPs PSMs. The HAPs PSMs were stable for one year within the uncertainty of 0.38%. The final uncertainty of the PSMs was determined by combining the preparation uncertainty, verification uncertainty, and stability uncertainty. Finally, traceable and stable HAPs PSMs at $1{\mu}mol/mol$ levels were developed with the uncertainty of less than 0.76% in high-pressure aluminum cylinders.