• 한국대기환경학회지
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• 제34권4호
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• pp.542-553
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• 2018

Since many previous studies reported the health effect of air pollution and indicated traffic as a major pollution source, significant policy efforts have been made to control traffic to reduce air pollution. However, there have been few studies that evaluated such policy implementation. In Seoul, Korea, the exclusive median bus lane system was implemented in 2004, and the metropolitan government applied air pollution reduction policies such as conversion of diesel buses to compressed natural gas buses and installation of emission control devices. This paper aimed to investigate the impact of the exclusive median bus lane system on air pollution reduction. Using hourly concentrations of particulate matter ($PM_{10}$) and nitrogen dioxide ($NO_2$) measured at 131 regulatory monitoring sites in Seoul and Gyeonggi-do for 2001-2014, we calculated annual and daily average concentrations at each site. We assessed the impact of the policy using differences-in-differences analysis by annual and daily average models after adjusting for geographic and/or meteorological variables. This method divides population into treatment and control groups with and without policy application, and compares the difference between the two time periods before and after the policy implementation in the treatment group with the difference in the control group. We classified all monitoring sites into treatment and control groups using two definitions: 1) Seoul vs. Gyeonggi-do; 2) within vs. outside 300 meters from the median bus lane. Pre- and post-policy periods were defined as 2001-2005 and 2006-2014, and 2004 and 2014 in the annual and daily models, respectively. The decrease in $PM_{10}$ concentrations between the two periods across monitoring sites in the treatment group was larger by $1.73-5.88{\mu}g/m^3$ than in the control group. $NO_2$ also showed the decrease without statistical significance. Our findings suggest that an efficient public transport policy combined with pollution abatement policies can contribute to reduction in air pollution.

• 한국해양생명과학회지
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• 제5권2호
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• pp.72-80
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• 2020

영산강 하구는 1981년에 농지 및 농업용수 개발을 위해 하굿둑이 건설되면서 인위적인 변형이 이루어진 시스템으로 하굿둑을 중심으로 담수역과 해수역으로 분리되었다. 하지만 여름철에는 잦은 강우로 인해 수문이 자주 개방되고, 개방 시에 담수가 해수역으로 방류되면서 기수역의 특성을 보이기도 한다. 본 연구에서는 담수 방류의 직접적인 영향을 파악하기 위해 2013년부터 2015년까지 여름철 동안 담수 방류 전후로 일간 모니터링을 실시하여 하계 식물플랑크톤 크기구조와 환경여건 변화를 파악하고자 하였다. 그 결과, 담수 방류는 급격한 염분감소와 탁도를 증가시켜 표층의 용존산소도 감소시키는 것으로 나타났다. 다만 조사 전까지 방류가 지속적으로 이루어진 2014년에는 이미 염분이 감소한 상황이어서 추가적인 방류로 인한 염분의 감소는 나타나지 않았다. 영양염 중에서는 특히 질소성 영양염의 유입이 크게 나타났고, 이로 인해 질소의 상대적 제한 보다는 인이나 규소의 제한 가능성이 크게 나타났다. 식물플랑크톤 생체량 및 크기구조는 연도별로 상이한 결과를 보였으나 결과적으로 담수 방류에 따라 변화를 초래하였고, 방류 후에도 어느 정도 그 경향이 유지되었다. 결론적으로 불규칙적이고 예측이 어려운 담수 방류는 염분, 탁도, 영양염 농도 등의 환경요인뿐만 아니라 식물플랑크톤의 생체량 및 크기구조를 단기적으로 크게 변화시키는 것으로 나타났다. 이러한 변화는 적조와 같은 유해조류발생(HABs) 뿐만 아니라, 먹이량 및 미세먹이망 변화를 통해 상위소비자 그리고 먹이망 구조에도 영향을 미칠 수 있을 것으로 사료된다.

• Tuberculosis and Respiratory Diseases
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• 제52권2호
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• pp.156-165
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• 2002

연구배경: 기관내 관에 의한 합병증 중에서 기낭에 연관된 문제로 높은 기낭압은 기관 점막의 허혈성 손상을 초래하고 너무 낮은 기낭압은 상기도 분비물의 흡인과 환기 가스의 누출에 따른 환기 장애를 초래한다. 이러한 기낭과 관련된 문제들을 예방하기 위해서는 적절한 기낭압을 유지하는 것이 중요하다. 더욱이 장기간 기계호흡을 받는 환자에서는 환자의 호흡역학의 변화 등 여러 원인에 의해서 적절한 기낭압이 변할 수 있어 기낭압의 지속적인 감시 및 관리가 필요할 것으로 사료되나 이에 대한 연구 보고가 없었다. 이에 본 연구는 장기간 기계호흡을 받는 환자에서 기관내관의 기낭압의 변화를 알아 보고 기낭압의 지속적인 감시 및 관리의 필요성을 알아보고자 하였다. 방 법 : 호흡부전으로 14일 이상 장기간 기계호흡을 받는 환자를 대상으로 기관 내관 삽관 일부터 발관 일까지 매일 기낭 공기량의 변화에 따른 기낭압의 변화를 알아 보고 적절한 기낭압을 유지하기 위해 필요한 기낭 공기량을 측정하여 비교하였다. 결 과 : 기낭압은 삽관 일수에 따라 유의한 증가는 관찰되지 않았으나 적절한 기낭압을 유지 하기 위해서 필요한 기낭내 주입 공기량은 환자에 따라 1.9~6.9 cc 로써 다양하고 동일한 환자 내에서도 적절한 기낭압을 유지하기 위해 필요한 기낭내 주입 공기량의 변화가 심하고, 일정한 기낭 공기 3cc 주입시 측정된 기낭압의 변화가 평균 22 $cmH_2O$였다. 수은혈압계로 측정된 기낭압은 자동기낭압관리기로 측정된 기낭압과 정확히 일치하였다. 결 론 : 기낭압에 의한 합병증을 줄이기 위해서 일정한 공기량을 기낭내 주입하거나 간헐적인 기낭압의 측정으로는 적절한 기낭압을 지속적으로 유지 하는데 부적절하여 지속적인 기낭압의 측정 및 감시가 필요한 것으로 사료되며 이러한 목적으로 수은혈압계는 자동기낭압관리기를 대체하여 이용될 수 있을 것으로 사료된다.

• 천문학회보
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• 제40권1호
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• pp.66.2-66.2
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• 2015

In today's age when telecommunications using satellite has become part of our daily lives, one has to be employ preventive measures to avert any possible danger, of which solar activity is the major cause. Coronal mass ejections (CMEs) heading towards the Earth can lead to disturbances in the Earth's magnetosphere, if their magnetic field is oriented southward. Monitoring of solar filaments in this case becomes very very crucial, as their eruption is associated with most of the CMEs. Monitoring of solar filaments in this case becomes very very crucial, as their eruption is associated with most of the CMEs. Also, filaments show activation up to a few hours prior to launch of a CME and thus can provide advance warning. In this study, we present an algorithm for the detection of solar filaments seen in the extreme ultraviolet (EUV) from Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO). Various morphological operations are employed to identify and extract the filaments. These filaments are then tracked in order to determine their size and location continuously.

• 한국환경과학회지
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• 제14권11호
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• pp.1035-1047
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• 2005

By using hourly $NO_2$ concentration data$(1998\~2000)$ at the Busan Metropolitan City air qualify monitoring sites, characteristics of daily mean value of $NO_2$ concentration was discussed in space and time. The correlation between $NO_2$ concentration and other relating air pollutants was analyzed by using SAS program and meteorological parameters as well. After choosing representative 4 areas, this study used hourly concentration data$(1998\~2000)$ from air quality monitoring sites on $NO_2,\;NO,\;O_3,\;CO,\;SO_2\;and\;PM_{10}$. Typical metropolitan characteristics of two peaks in a day was shown in the variation of $NO_2$ concentration of Busan city.

• 한국환경과학회지
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• 제14권11호
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• pp.1049-1056
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• 2005

[ $NO_2$ ] concentration characteristics of Busan metropolitan city was analysed by statistical method using hourly $NO_2$ concentration data$(1998\~2000)$ collected from air quality monitoring sites of the metropolitan city. 4 representative regions were selected among air quality monitoring sites of Ministry of environment. Concentration data of $NO_2$, 5 air pollutants, and data collected at AWS was used. Both Stepwise Multiple Regression model and ARIMA model for prediction of $NO_2$ concentrations were adopted, and then their results were compared with observed concentration. While ARIMA model was useful for the prediction of daily variation of the concentration, it was not satisfactory for the prediction of both rapid variation and seasonal variation of the concentration. Multiple Regression model was better estimated than ARIMA model for prediction of $NO_2$ concentration.

• 대한의용생체공학회:의공학회지
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• 제38권5호
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• pp.264-270
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• 2017

A Doppler radar sensor was applied to detect respirations and heartbeats of persons who were lying on a bed. This study is preliminary study aiming at non-contact and non-intrusive respiration and heart rate monitoring during sleep in daily life. For the experiments, 10GHz Doppler radar with patch-type antenna was used and installed on the upper right and the distance between the body and the antenna was 1 m. The results show that each signal of respiration and heartbeat is observed in each frequency band however the frequency band and the waveform vary according to the subjects and the posture. The results show that the heartbeats can be detected with the peak detection in some frequency band. This study shows the feasibility of applying the Doppler radar to detection of heartbeat and respiration during sleep and further studies about heartbeat detection algorithm are required.

• Smart Structures and Systems
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• 제14권3호
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• pp.367-376
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• 2014

Ambient vibration techniques are nowadays a very popular tool to assess dynamic properties of buildings. Due to its non destructive character, this method is particularly valuable, especially for health monitoring of historical monuments. The present ambient vibration experiment consists on the evaluation of vibration modes of a Medieval tower. Situated in Soncino (close to Cremona, in the Northern Italian region named Lombardia), the tower of 41.5 meters height has been monitored by seismometers located at different points inside the structure. Spectral ratios of the recorded ambient vibrations clearly identify a fundamental mode at about 1 Hz, with a slight difference in the two horizontal components. A second mode is also evidenced at approx 4-5 Hz, with a moderate degree of uncertainty. The records of a ML 4.4 earthquake, occurred during the monitoring period, confirm the information obtained by microtremor analysis. Daily variations of both 1st and 2nd mode were detected: these variations, of an amount up to 2%, seem to be well related with the temperature.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.379-381
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• 2005

Urodynamics describes a collection of tests designed to evaluate lower urinary tract function and can be performed using retrograde filling of the bladder within a room. In this study, we designed and calibrated the potable urodynamics monitoring system using DSP chip (TMS320VC33, Texas InstrumentTM, U.S.) and obtained signals of bladder(Pves) and bladder neck pressure(Pneck) and EMG using calibration kit (DPT9022K0122, MedtronicsTM, U.s,). This system monitor spontaneous urination during daily life and can make patients more comportable.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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• pp.402-405
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• 2008

This paper is a proposal of Sentinel Asia for Environment (SAFE). The essential to this project is to help environmental agencies in Asia to set up an environmental monitoring system with satellite observation data. It is focused on an environmental issues originated from anthropogenic events detected as land cover and land use change in Asians' daily human life including; agriculture, global warming gas, urban environment and forest resources. It is leaded by Japan Aerospace Exploration Agency (JAXA) along with University of Tokyo and Asian Institute of Technology in Thailand under the umbrella of Sentinel Asia which is dedicated to disaster monitoring issues. It is expected to initiate a information outgoing through WWW for Asian countries to set up their national land information system focusing on environmental changes.