• 한국대기환경학회지
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• 제33권6호
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• pp.544-553
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• 2017

There is an overall guideline of the installation of air quality monitoring stations in Korea, but specified steps for the selection of monitoring sites for hazardous air pollutants(HAPs) are not provided. In this study, we proposed a systematic method for the selection of monitoring sites for HAPs using geographic information system (GIS). As a case study, the Seoul metropolitan area (Seoul, Incheon, and Gyeonggi Province) was chosen, and 15 factors including population, vehicle registration, and emission data were compiled for each grid cell ($7km{\times}7km$). The number of factors above the top 30% of individual data for each grid cell was used to select priority monitoring sites for HAPs. In addition, several background sites were added for data comparison and source identification. Three scenarios were suggested: Scenario 1 with 7 sites, Scenario 2 with 17 sites, and Scenario 3 with 30 sites. This proposal is not the final result for an intensive monitoring program, but it is an example of method development for selecting appropriate sampling sites. These results can be applied not only to HAPs monitoring in megacities but also to the national HAPs monitoring network.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.94-96
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• 2003

Since 1995, MOCT(Ministry of Construction and Transportation) and KOWACO(Korea Water Resources Corporation) have established the National Groundwater Monitoring Network in South Korea and also MOE(Ministry of Environment) has operated Groundwater Quality Monitoring network. Until 2001, 202 monitoring stations by MOCT and 780 monitoring wells by MOE have been constructed, measured groundwater level and analyzed water samples. Groundwater quality analysis has been conducted two times a year during last 6 years for all monitoring wells. The quality data has about 15 components including pH, COD, Count of Coliform group, and etc.. Trend analysis has been peformed for 6 components(Coliform, pH, COD, NO$_3$-N, Cl and EC) of water quality which are analyzed more than 7 times for total monitoring wells. Two test methods have been used ; Sen's test and Mann-Kendall test. These trend tests have been done at the 0.05 significance level. By the result of Sen's test, Count of Coliform group has either upward or downward trends at 4.3 percent of the monitoring points. pH does at 5.6 percent, COD does at 8.6 percent, Nitrate-Nitrogen does at 13.2 percent, Chloride does at 13.4 percent, and. EC does at 11.6 percent of the monitoring points. The exact causes of the groundwater quality trends are difficult to specify. Notable downward trends in nitrate at many monitoring points may be the result of reduction on some contamination sources. Potential causes include diminished agricultural areas, improvements in sewage treatment and a decrease in atmospheric deposition. Increase in chloride at many monitoring points may be the result of increased non-point source pollution such as road salting and runoff from sprawling paved developments and suburbs.

• 정보과학회 논문지
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• 제43권11호
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• pp.1223-1232
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• 2016

가상 네트워크 기술은 다양한 서비스의 요구조건을 반영한 네트워크를 제공할 수 있다. 다양한 서비스의 요구조건을 반영하기 위해 효율적인 리소스 분배 기술이 필요하다. 기존의 트래픽 대역폭 분배 기법들은 다운링크 트래픽만 제어하거나 네트워크의 트래픽 상황을 고려하지 않는다. 무선 네트워크에서 다운링크와 업링크는 같은 자원을 공유한다. 또한, 기존의 트래픽 대역폭 분배 기법들은 모든 스테이션이 포화된 트래픽을 발생시킨다고 가정한다. 그래서 기존의 트래픽 대역폭 분배 기법들은 가상 무선 네트워크에서 트래픽 제어를 할 수 없다. 본 논문에서는 이러한 문제들을 해결하기 위해 트래픽 기반 대역폭 제어 기법을 제안한다. 가상 네트워크에 SDN을 적용하고 각 스테이션의 트래픽을 모니터링하고 비포화 트래픽을 발생시키는 스테이션을 탐색한다. 또한, 모니터링 정보를 기반으로 업링크와 다운링크 트래픽을 동적으로 제어한다. 실제 테스트베드 구성 후, 기존의 기법과 비교 결과, 트래픽 대역폭 분배 성능이 최대 14% 개선되었다.

• 한국대기환경학회지
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• 제25권5호
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• pp.459-471
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• 2009

Air Monitoring Network(11 urban stations) is operated to measure ambient air quality in Daegu city. The urban air monitoring stations include 6 in residence area, 3 in industrial area, 1 in commercial area, and 1 in green area. In this study, hourly data (2006. 1. 1~2008. 12. 31) of $PM_{10}$ were measured at 11 urban air monitoring stations. $PM_{10}$ mean concentrations were high in fall and winter because of low wind speed and many haze days. The number of exceeding the daily standard of $PM_{10}$ in industrial area was approximately twice as many as that in residence area. $PM_{10}$ concentrations and visibility were influenced significantly by wind speed. Wind speed and visibility were below 1.8 m/s and 10 km, respectively when $PM_{10}$ concentrations were over $120{\mu}g/m^3$. $PM_{10}$ concentrations were high when haze was observed. The mean concentrations of $PM_{10}$ were $104{\pm}41.3{\mu}g/m^3$, $63{\pm}35.1{\mu}g/m^3$, and $49{\pm}26.9{\mu}g/m^3$, respectively when haze, mist and clear were observed.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2007년도 공동학술대회 논문집
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• pp.163-166
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• 2007

KMA established short period seismometer, accelerometer, and ocean bottom seismometer network to build the detail earthquake monitoring system and Tsunami monitoring system. KMA also replaced borehole seismometer and wave height meter monitoring system. The purposes of this study are to record the ambient seismic noise levels of short period seismometer and accelerometer installed in 2006 and 2007, and compare their characteristics to present the standard of site selection criteria.

• International Journal of Aeronautical and Space Sciences
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• 제17권1호
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• pp.64-72
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• 2016

The coverage area of a GNSS regional ionospheric delay model is mainly determined by the distribution of GNSS ground monitoring stations. Extrapolation of the ionospheric model data can extend the coverage area. An extrapolation algorithm, which combines observed ionospheric delay with the environmental parameters, is proposed. Neural network and least square regression algorithms are developed to utilize the combined input data. The bi-harmonic spline method is also tested for comparison. The IGS ionosphere map data is used to simulate the delays and to compute the extrapolation error statistics. The neural network method outperforms the other methods and demonstrates a high extrapolation accuracy. In order to determine the directional characteristics, the estimation error is classified into four direction components. The South extrapolation area yields the largest estimation error followed by North area, which yields the second-largest error.

• 전자공학회논문지 IE
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• 제46권4호
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• pp.66-72
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• 2009

환경분야에서 산업화와 도시화에 따른 수질오염의 문제를 해결하기 위해 오수처리시설을 제어 및 감시하는 장치들이 개발 되어 왔다. 본 연구에서는 지역에 설치된 오수처리시설의 구동 모터와 주변 환경 상태를 제어하고 감지하기 위하여 시리얼 인터페이스를 갖는 내부 네트워크로 상호 연결한 효율적인 모듈 시스템의 설계방법에 대하여 제안하였다. 본 연구에서 제안된 방법은 급변하는 환경시장에서 요구되는 조건과 환경인자들의 사양에 대하여 보다 적응성 있고 유연한 설계 기법을 제공하리라 기대된다.

• 한국컴퓨터정보학회논문지
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• 제7권1호
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• pp.74-79
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• 2002

환경분야에서 산업화와 도시화에 따른 수질오염의 문제를 해결하기 위해 오수처리시설을 감시하는 장치들이 개발되고 있다. 본 연구에서는 원격지의 운영자가 여러 지역에 설치된 오수처리장치의 가동 상태를 확인하고 점검할 수 있는 가동상태 확인기기 네트워크의 운영 소프트웨어를 제안하였다. 소프트웨어는 개발된 하드웨어를 통해 실행되며, 데이터베이스, 데이터전송, 가동상태 분석을 위한 프로그램모듈로 구성된다 본 연구를 수행한 결과로서 환경 장비의 운영 관리의 효율성을 개선할 수 있음을 확인하였다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권1호
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• pp.22-32
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• 2012

This study suggests a method to grade groundwater quality quantitatively using statistical approaches for evaluating the quality of groundwater in wells included in the Groundwater Quality Monitoring Network (GQMN). The proposed analysis method is applied to GQMN data from 2001 to 2008 for nitrate nitrogen, chloride, trichloroethylene, potential of hydrogen (pH), and electrical conductivity. The analysis results are obtained as groundwater quality grades of the groundwater representing each of the monitoring stations. The degree of groundwater contamination is analysed for water quality parameters, district, and usage. The results show that the degree of groundwater contamination is relatively high by nitrate nitrogen, bacteria and electrical conductivity and at Seoul, Incheon, Gwangju, Gyeonggido and Jeollado. The degree of contamination by nitrate nitrogen and trichloroethylene is especially high when the groundwater is used for agricultural and industrial water, respectively. It is evaluated that potable groudnwater in GQMN is significantly vulnerable to nitrate nitrogen and bacteria contamination.

• 한국측량학회지
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• 제26권6호
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• pp.617-624
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• 2008

일반적으로 단일기준국을 이용하는 실시간 동적(Real Time Kinematic) GPS는 무선모뎀을 통해 반송파 오차보정량을 이동국으로 전송하여 현장에서 바로 고정밀의 위치를 결정할 수 있다. 하지만 단일기준국 방식은 각 위성마다의 시간대별 반송파 측정값을 지속적으로 제공해야 하며, 전송장해와 모뎀간의 거리 따른 증가 등으로 위치정확도가 저하되는 단점이 있다. 본 논문은 이러한 단점을 보완하기 위해 3대 이상의 다중기준국을 활용한 네트워크 기반의 GPS 반송파 상대측위기술을 구현하였으며, Visual C++로 제작된 실시간 모니터링 프로그램을 이용하여 RTK 네트워크를 구성하였다. 네트워크 구성에서 얻어지는 다중기준국의 오차보정량 가운데 최적의 값을 자동으로 선택하고, GPS buoy 이동국에 적용하여 해수면 관측을 수행하였으며, 이를 통해 얻어진 해수면 변동량을 단일기준국과 비교, 분석하여 결과를 도출하였다.