• 한국멀티미디어학회논문지
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• 제23권11호
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• pp.1372-1382
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• 2020

This paper proposes a core technology for a micro river monitoring terminal device suitable for flood monitoring in small rivers and valleys. Our proposed device is basically equipped with a 77GHz radar, gyro and accelerometer sensors. To measure the flow velocity and water level, we proposed a signal processing technique that extracts pure water energy components from the observed Doppler velocity and reflection intensity from the radar. And to determine the stability of the river structure equipped with our device, we constantly monitor the displacement of the measured values of the gyro and accelerometer sensors. Experimental result verified that our method detects pure water energy in various river environments and distinguishes between flow velocity and water level well. And we verified that vibration and position change of structures can be determined through a gyro sensor. In future research, we will work to build a secure digital twin river network by lowering the cost of supplying RF-WAV devices. Also we expect our device to contribute to securing a preventive golden time in rivers.

• Biotechnology and Bioprocess Engineering:BBE
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• 제2권2호
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• pp.141-146
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• 1997

A new sensing system based on the immobilization of luminescent batcteria, Photobacterium phosphoreum, was proposed for continuous real-time monitoring of polluants. The response curves demonstrate that Photobacterium phosphoreum immobilized on the strontium alginate was very sensitive to seven reference chemicals used. The significant inhibitory concentrations for bioluminescence emission were 5 ppm for Pb(NO3)2, NiCl2, CdCl2, 50 ppm for NaAsO2, 0.1ppm for HgCl2, 0.5ppm for pentachlorophenol and less than 5ppm for SDS, respectively. The alginate mixed-cells (AMC) retained their luminescence during experimental period (29 days) under storage condition of -8$0^{\circ}C$. The variables affecting performance of continuous flow through monitoring (CFTM) were optimized in order to ensure stability and efficiency. The flow through cell with strontium-alginate immobilized luminescent bacteria was tested with salicylate and 4-nitrophenol and a rapid response of luminescence was recorded by time drive mode in bioluminescence spectrometer after exposure to both toxicants.

• 한국CDE학회논문집
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• 제14권6호
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• pp.424-433
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• 2009

In order to improve productivity and efficiency of ship production process, production technology converged with Information Technology can be considered. Mid-term scheduling based on long-term schedule of ship building and execution planning based on short-term production schedule have an important role in ship production processes and techniques. However, data used in the scheduling are from the experiences of the past, cognitive, and often inaccurate, moreover the updates of the data by formatted documents are not being performed efficiently. This paper designs the tracking and monitoring system for the curved plates forming process with shop level. At first step to it, we redefine and analyze the curved plates forming process by using SysML. From the definition and analysis of the curved plates forming process, we design the system with respect to operational view considering operational environment and interactions between systems included and scenario about operation, and with respect to system view considering functionalities and interfaces of the system. In order to study the feasibility of the system designed, a prototype of the system has been implemented with 13.56 MHz RHD hardware and application software.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.466-474
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• 2008

The purpose of this study was to comparatively analyze the measured values and modelling values when a sample mountain was cut and thereby, assess the fitness of the prediction model. For this purpose, the researcher analyzed the relationship between the groundwater levels measured at 7 monitoring holes set within the area of the underground flow prediction model and the levels of the groundwater monitoring holes before and after mountain cutting. As a result of this analysis, it was found that the MODFLOW program itself was limited and uncertain in terms of calibration of the modelling values. Since the model was based on the assumption that the same amount of rainfalls would permeate into the ground when the sample mountain area was cut up to 50m high, it was deemed inevitable that the result of modelling was different from the actual measurement.

• Journal of Radiation Protection and Research
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• 제22권2호
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• pp.111-117
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• 1997

최근 포괄적 핵실험금지조약 (Comprehensive Test Ban Traety : CTBT)의 체결은 전세계적으로 핵활동 감시 네트워크를 구축하는 것이다. 핵실험금지 위원회의 전문가들은 대기 방사성핵종의 측정을 핵실험 감시에 필수적인 요소로 제안하였으며, 이에 따른 기술적 요구사항을 제시하였다. 본 연구는 이를 근거로 핵활동으로부터 생성된 핵분열생성물을 검출하기 위하여 고성능 공기채집장치(High Volume Air Sampler: HVAS)와 여과지 압축기 그리고 고순도 게르마늄 반도체검출기(HPGe)로 대기 입자 방사성핵종 측정시스템을 구성하였다. 조속한 시일 내에 탐지와 최적의 측정 조건으로 본 시스템을 운영하기 위하여 CTBT 감시 전략에서 주요 핵종들에 대한 최소검출 방사능 농도(Minimum Detectable Concentration : MDC)를 decay time, counting time 그리고 sampler volumetric flow rate 등을 고려하여 결정하였다. 그 결과 각각 $10{\pm}$2h, $20{\pm}$2h, $850{\pm}50m^3$//h 정도로 선정하였다. 감마선 스펙트럼 분석에서 $^{212}Pb$ 방사능 농도의 변화는 Compton continuum의 baseline에 영향을 미치게 되므로 이에 기인한 MDC 관계식을 도출하였다. 이들 결과는 CTBT 감시 전략에 실제적인 도구로 사용될 수 있을 것으로 사료된다.

• 한국수자원학회논문집
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• 제38권8호
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• pp.655-664
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• 2005

저수지를 통한 수자윈의 지속적 확보와 이용에 걸림돌이 되고 있는 탁수의 장기발생문제를 기술적으로 해결하고자 실시간 탁수 감시와 예측시스템(RTMMS)을 구축 중이며, 2004년 홍수기 동안 대청호를 대상으로 유입하는 탁수의 수리 및 수질특성을 조사하고 2차원 횡방향 평균 수리 및 수질모형인 CE-QUAL-W2(W2)를 적용하여 탁수의 밀도류 거동과 시${\cdot}$공간적 분포를 예측하고 실측값과 비교하여 모형의 적용가능성을 평가하였다. 강우사상 동안 하천 수온은 $5{\sim}10^{\circ}C$ 정도 하강하였으며 탁수가 저수지내에서 밀도류를 형성하는 원인으로 작용했다. 적용된 W2모형은 수온의 성층구조 변화와 탁수의 침강점, 도달시간, 중층밀도류 두께 등 탁수의 거동특성을 비교적 잘 모의하였다. 그러나 국부적으로 탁수가 위치한 중층과 탁수 유입 전에 형성되었던 전이층에서 수온과 탁도의 모의값과 실측값이 유의할 만한 오차를 보였다. 펜티엄급 PC(CPU 2.0GHz)로 홍수기 전체기간 모의에 소요된 시간은 약 4분으로써 모형은 계산의 효율성 측면에서 실시간 모의에 적합한 것으로 평가된다.

• 한국지반공학회논문집
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• 제26권5호
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• pp.37-48
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• 2010

본 연구에서는 침투압이 주기적으로 변화하는 연근해 가물막이 시공현장에 적용하기 위해서 수두손실그래프에 의한 침투류 감시기법을 개발하였다. 이 기법에서 새로이 정의된 수두손실율은 0~1 사이의 값으로 나타나며 0이면 완전통수상태, 1이면 완전차수상태를 나타낸다. 수두손실그래프의 결정계수가 1에 가까우면 침투경로상의 지반은 안정된 상태에 있음을 나타내고 0에 가까우면 공동이 존재할 수도 있고 파이핑이 진행 중일 수도 있다. 수두손실그래프에 의한 안전관리기법은 침투상태의 변화를 민감하게 감지할 수 있도록 하며 전체 현장에 적용할 경우 각 위치별 하부지반의 침투상태를 세부적으로 판단할 수 있도록 한다.

• 한국대기환경학회지
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• 제18권4호
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• pp.285-295
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• 2002

In this study, several types of gravimetric methods (such as high, medium, low, and ultra low volume sampling methods) were applied to determine suspended particulate matter concentrations in both ambient and indoor environments. Comparative evaluations were undertaken with SPM data obtained using a variety of samplers (TSP, PM10, and PM4.0) at different sampling flow rates. Correlation coefficients between TSP and PM10 concentrations measured at different flow rates fell in the range of 0.73∼0.94 (n=40). In addition, correlation coefficients for PM concentrations measured by different TSP samplers were in the range of 0.90∼0.95 (n=36 or n=38), while 0.77∼0.91 (n=38) for PM10 samplers. Correlation analysis was also conducted on indoor monitoring data that were measured using ultra-low-volume samplers at both different or identical flow rates. The correlation coefficients were in the range of 0.98∼0.99 (n=38) between TSP and TSP and 0.92∼0.94 (n=38) between TSP and PM10. The mean ratio for high volume PM10 to TSP concentration that was monitored at identical flow rates in the ambient air appeared to be 0.72. The mean ratios of PM10 to TSP and PM4.0 to TSP observed with identical flow rates at indoor environments were 0.47 and 0.40. The results of this study may provide empirical information concerning the compatability of aerosol data obtained by gravimetric sampling methods at different flow rates.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.241-243
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• 2001

On-line monitoring technique for the concentration of lactate by a FIA(Flow Injection Analysis) system was studied. The lactate oxidase(LOD) was immboilized on VA-Epoxy carrier and integrated into the FIA system. The pH, buffer flow rate and temperature for the LOD-FIA were optimized, and the effects of salts and metabolites dissolved in the sample on the activity of immobilized enzyme were investigated. The LOD-FIA has been applied to monitor the concentrations of lactate in a simulated bioprocess. The on-line monitoring data by the LOD-FIA agreed with the off-line data measured by a fluorescence spectroscopy well.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2006년도 학술발표회 논문집
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• pp.746-751
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• 2006

The geumjunggu of the onchunchun which is the upper stream have been maintained as a too much picture to become a concrete lining about existing low flow channel and the reservoir water protecting banks for the reason of the flow of an upper stream steep slope and back of the shortage of the channel area in a suitableness interval. This research made a rating-curve to decide since to ensure against risks to the flood control through the undo of the rivers. And we found the speed of current of a nature undo interval and existing concrete interval and water level change out. A result from this natural disposition we must apply as a data for the research about the plan to be established in the rivers maintenance basis plan of onchunchun.