• Journal of Soil and Groundwater Environment
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• v.12 no.3
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• pp.66-74
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• 2007

Stationary and trolling methods in measuring flow using flowmeter were adopted to investigate the hydraulic connectivity of fractures and to evaluate the applicability of the measurement methods. Stationary method was useful for identifying the inflow and outflow patterns in the measured section, which enabled us to analyze the hydraulic connectivity of fractures between the wells. Trolling method failed to find the inflow and outflow patterns in the well, but was very effective for locating the conductive fractures. Measuring flow in the borehole by both stationary and trolling methods was found to be very efficient for identifying conductive fractures and their hydraulic connectivity in fractured rock aquifer.

• Journal of Internet Computing and Services
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• v.17 no.1
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• pp.7-14
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• 2016

Recently, as cloud computing technologies are developed, it enable to work anytime and anywhere by smart phone and computer. Also, cloud computing technologies are suited to reduce costs of maintaining IT infrastructure and initial investment, so cloud computing has been developed. As demand about cloud computing has risen sharply, problems of power consumption are occurred to maintain the environment of data center. To solve the problem, first of all, power consumption has been measured. Although using power meter to measure power consumption obtain accurate power consumption, extra cost is incurred. Thus, we propose prediction method about power consumption without power meter. To proving accuracy about proposed method, we perform CPU and Hard disk test on cloud computing environment. During the tests, we obtain both predictive value by proposed method and actual value by power meter, and we calculate error rate. As a result, error rate of predictive value and actual value shows about 4.22% in CPU test and about 8.51% in Hard disk test.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2005.11a
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• pp.424-425
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• 2005

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2004.05a
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• pp.234-236
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• 2004

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.11a
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• pp.126-127
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• 2004

• Journal of the Korean Association of Geographic Information Studies
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• v.26 no.4
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• pp.218-236
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• 2023

This study attempted to analyze the environmental equity of fine dust(PM₁₀) in Daegu using MGWR(Multi-scale Geographically Weighted Regression) and KT(Korea Telecom Corporation) sensor data. Existing national monitoring network data for measuring fine dust are collected at a small number of ground-based stations that are sparsely distributed in a large area. To complement these drawbacks, KT sensor data with a large number of IoT(Internet of Things) stations densely distributed were used in this study. The MGWR model was used to deal with spatial heterogeneity and multi-scale contextual effects in the spatial relationships between fine dust concentration and socioeconomic variables. Results indicate that there existed an environmental inequity by land value and foreigner ratio in the spatial distribution of fine dust in Daegu metropolitan city. Also, the MGWR model showed better the explanatory power than Ordinary Least Square(OLS) and Geographically Weighted Regression(GWR) models in explaining the spatial relationships between the concentration of fine dust and socioeconomic variables. This study demonstrated the potential of KT sensor data as a supplement to the existing national monitoring network data for measuring fine dust.

• Proceedings of the Korean Society of Computer Information Conference
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• 2015.07a
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• pp.91-92
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• 2015

현재 실외 대기 중 미세먼지농도는 한국환경공단으로부터 지역별 실시간 정보를 받아볼 수 있다. 하지만 일반가정이나 사무실, 개개인이 있는 실내의 지속적인 공기상태는 사용자가 직접 미세먼지를 측정하는 기기를 사용하여 측정해야 만이 확인이 가능하기 때문에 쉽게 알기가 어렵다. 언제 어디서든 손쉽게 공기오염도를 측정 할 수 있으며 오염도가 심한 수준일 경우 사용자가 즉시 알 수 있다면 이를 조금 더 손쉽게 예방하고 대처할 수 있을 것이다. 본 논문에서는 공기의 질을 측정 할 수 있는 휴대용 측정기와 개인이나 가정의 실내 공기의 질을 손쉽게 측정할 수 있는 실내측정기를 개발하여 사용자가 실시간으로 측정된 정보를 받을 수 있도록 하는 시스템의 개발내용에 대해 기술한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.7
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• pp.3214-3219
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• 2011

Nowadays, we live in the age of highly developed information technology. The information industry is growing rapidly and it is making remarkable changes in our life. Among the information technologies, laser range finder can be used to measure distance in difficult environment. In this paper, we have designed and constructed the laser range finder for many purposes such as industry or leisure in difficult environment. Using the proposed laser range finder enables us to measure distance easily using timing discriminator between transmitter and receiver for industry or leisure.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.195-195
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• 2023

유기물오염은 호수와 하천에서 가장 흔히 나타나는 오염의 형태이다. 개발도상국에서는 하수처리시설이나 생활용수처리시설에서 유기물이 처리되지 않아 수중의 유기물함량이 증가하여 피해가 나타난다. 물환경보전법에 따라 유기물질을 측정하는 지표에는 BOD, COD, TOC가 있다. 그 중 BOD, COD 측정은 절차가 복잡하고 오래 걸리며, 생물분해가 불가능하거나 유독물질이 존재하는 유기물질인 경우에는 낮은 결과 또는 측정이 불가능하다. 이러한 이유로 환경부에서는 TOC중심관리로 전환되고 있다. 대부분의 수질항목 측정의 경우 현장시료를 채취하여 실험실에서 분석하는 수분석을 이용한다. 하지만 수분석의 경우 인력이 많이 투입되고 분석수가 한정적이며, 정교한 과학 장치를 갖춘 전문 실험실을 필요로 한다. 반면에 TOC는 짧은 시간 내에 측정이 가능하고, 안정적인 산화로 유기물질 총량을 정확하게 측정이 가능하다. 또한 위해성 물질을 발생시키지 않는 친환경적 방법이라 환경오염 감시에 많이 활용된다. 본 연구에서 분광측정기 중 하나인 S-CAN을 통해 하천의 TOC분석을 진행하였다. 대상지는 안동에 위치한 하천실험센터와 금호강 진천천으로 S-CAN측정과 채취한 시료의 수분석 결과를 비교하였다. 이를 통해 TOC측정 및 기기에 대한 정확도분석을 실시하였다. 본 연구를 통해 S-CAN을 활용한 TOC중심의 수질모니터링하여 수질의 특성을 탐구하고, TOC기초연구를 통한 유기물오염도 지표로서 해석할 수 있다. 수분석 자료를 활용한 정확도 비교를 통해 하천 TOC센서 측정 적용에 대한 기초자료 제공과 측정기기의 현장적용성을 판단 할 수 있다. TOC측정 및 분석을 통해 유기물질량을 실시간으로 정확하게 측정하게 되면 수질관리 효율성이 높아지고, 하천에 유입되는 유기물질량과 농도를 정확하게 파악하여 실효성 있는 정책 수립 및 효율적인 수질관리를 할 수 있다.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.6
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• pp.606-613
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• 2005

The badge-type diffusive sampler for the measurement of formaldehyde in indoor air using three types of colorimetric methods such as chromotrophic acid(CTA), 3-methyl-2-benzothiazolinone hydrazone(MBTH), and 4-amino-3-hydrazino-5-mercapto-1,2,4-triazole(AHMT) method. The washing of the collection filter with several cleaning solution was effected with satisfactory results, regardless of the types of cleaning solutions. The concentrations of absorbance solution in each colorimetric method were experimentally determined by considering the sampling rates. The variation blank values in each colorimetric method was below 15%. As compared with CTA and AHMT methods, the reproducibility of MBTH method was excellent and was below 10% relative standard deviation. The collected formaldehyde mass and time-weighted concentration had a good correlation (correlation coefficient > 0.93). The limit of detection and limit of quantitation, and minimum sampling time were closely correlated to the sampling rates for the measurement of formaldehyde in each method.