• 대한원격탐사학회지
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• 제14권3호
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• pp.296-306
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• 1998

Airborne MSS 자료는 수질오염을 효과적으로 감시하고 분석할 수 있는 자료이다. 본 연구에서는 다목적 실용위성(KOMPSAT)에 탑재될 저해상도카메라(LRC)의 다중분광 영상자료를 수질오염 분석에 활용할 목적으로 수질인자의 분광반사도를 측정하였으며, 고해상도 원격탐사 자료인 Airborne MSS 자료를 이용하여 수역에서의 수질인자 추출 가능성을 조사하였다. 특히 부영양화와 관련된 환경인자 추출을 시도하였다. 수질인자는 클로로필-a, 부유물질, 탁도 등을 선정하여 분광반사 특성 및 처리기법을 개발하였다. 그 결과는 다음과 같다 첫째, 수면에 도달하는 태양광 스펙트럼은 가시광 영역인 0.4~0.7$\mu\textrm{m}$에서 전체 복사량의 50% 정도가 반사되며, 0.50$\mu\textrm{m}$ 부근에서 가장 높다. 둘째, 클로로필-a는 녹색 파장대인 0.52$\mu\textrm{m}$, 부유물질의 반사도는 0.8$\mu\textrm{m}$, 탁도는 0.57$\mu\textrm{m}$에서 높은 반사율을 보였다. 셋째, Airborne MSS자료를 이용하여 수질인자 분석결과, 클로로필-a는 Band 3과 Band 7을 비연산처리를 하여 분포도를 작성하였다. 부유물질은 Band 7에서 분포도를 작성할 수 있었으며, PCA를 수행하였을 때 PC 1에서 유용함을 알 수 있었다. 탁도는 PCA 분석시 PC 4에서 현장자료와 유사한 분포패턴을 나타내었다. 이상의 결과들은 계절적, 시간적 변화에 따라 파장대역이 달라질 수 있으므로, LRC 자료를 이용하여 보다 정확한 수질환경 인자를 분석하기 위해서는 현장실측 자료 및 수역의 분광반사 특성 등을 지속적으로 조사할 필요가 있다. 추후 본 연구에서는 저해상도 위성영상 및 현장 분광반사도 측정을 통한 수역의 분광반사 특성을 지속적으로 분석하고, 수역의 수질분석자료 확보 및 수질오염 유형을 분석 할 것이다.

• 한국항공우주학회지
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• 제41권7호
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• pp.577-587
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• 2013

본 논문은 항공기용 다기능 레이더의 통합적 자원관리를 수행하는 자원관리자와 레이더/환경 시뮬레이터 구축에 대한 연구 결과를 설명한다. 레이더/환경 시뮬레이터는 항공기 레이더의 표적 탐지/측정 모델, 탑재된 레이더의 좌표변환을 고려한 추적 필터 및 효율적인 표적 생성 알고리듬을 포함한다. 항공기 레이더 자원관리 알고리듬의 각 모듈별 구조와 기능을 도출하고, 구축된 레이더/환경 시뮬레이터를 통해 시험 검증하였다.

• Environmental Analysis Health and Toxicology
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• 제19권2호
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• pp.169-176
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• 2004

ETS (environmental tobacco smoke) is composed of exhaled mainstream smoke (MS) from the smoker, sidestream smoke (SS) emitted from the smoldering tobacco between puffs and contaminants that diffuse through the cigarette paper and mouth between puffs. These emissions contain both vapor phase and particulate contaminants. ETS is a complex mix of over 4,000 compounds. This mix contains many known or suspected human carcinogens and other toxic agents. More of these toxic compounds are found in SS than in MS. Workplace exposure to ETS can result in significant smoke intake, and passive smoke exposure may be related to impair respiratory function and an increase risk of lung cancer in nonsmokers. For nonsmokers sharing a work environment with cigarette smokers, the workplace must be considered hazardous independently of any specific industrial toxic exposure. The risk is particularly important when a high percentage of the workers smoke or where smokers and nonsmokers work in poorly ventilated areas. Nicotine is converted in the body to cotinine; cotinine therefore can be used as an indirect measure of a person's recent exposure to tobacco smoke. Levels of nicotine in hair and levels of cotinine in body fluids (saliva and urine) have been shown to increase with increasing environmental nicotine levels and with self-reported ETS exposure. The measurement of nicotine or cotinine in hair may be more appropriate for longer-term exposure to tobacco. The purpose of this study is to comparing airborne nicotine levels and hair cotinine level in restaurant workers. Concentration of airborne nicotine and hair nicotine (and cotinine) is closely related to exposed frequency of sidestream smoke in the workplace. Nicotine in hair is a better predictor of airborne nicotine than hair cotinine. Hair nicotine can be a useful tool to assess ETS exposure interventions. It may have limiting levels of ETS exposure by placing regulatory restrictions on smoking in workplaces and in public spaces.

• 한국산림과학회지
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• 제96권3호
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• pp.251-258
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• 2007

항공 Lidar 기술을 이용한 산림조사 기법은 현지조사 및 항공사진을 이용한 기존 조사방법의 한계를 극복할 수 있는 대안으로 떠오르고 있다. 본 연구에서는 국내 산림지형의 특성을 고려하여 개체목 인식 및 수고(樹高)추출을 위한 항공 Lidar자료의 기본적인 처리기법을 제시하고자 한다. 경기도 유명산 조림지를 대상으로 촬영된 항공 Lidar 원시자료로부터 비지면점을 제거하는 기법을 적용하여 순수 지표면을 표현하는 수치표고모형자료(DEM)를 생성하였다. 이렇게 제작된 DEM자료를 기반으로 비지면점에 해당하는 신호값들을 추출한 후 수관고모형(CHM)자료를 생성하였다. CHM자료에 개체목의 수고를 추출하는 필터링 기법을 개발하였다. 연구 지역의 낙엽송 및 잣나무 표본임분을 대상으로 항공사진 및 현지 측정된 자료와 비교한 결과, 개체목의 본수는 90% 이상의 정확도로 추출되었으며, 수고는 평균 1.1m 낮게 추정되었다.

• 한국소음진동공학회논문집
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• 제22권10호
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• pp.985-993
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• 2012

In this paper, a new method is proposed to estimate the sound pressure generated from gasoline direct injection (GDI) engine. There are many noise sources as much as components in GDI engine. Among these components, fuel pump, fuel injector, fuel rail, pressure pump and intake/exhaust manifolds are major components generated from top of the engine. In order to estimate the contribution of these components to engine noise, the total sound pressure at the front of the engine is estimated by using airborne source quantification (ASQ) method. Airborne source quantification method requires the acoustic source volume velocity of each component. The volume velocity has been calculated by using the inverse method. The inverse method requires many tests and has ill-condition problem. This paper suggested a method to obtain volume velocity directly based on the direct measurement of sound intensity and particle velocity. The method is validated by using two known monopole sources installed at the anechoic chamber. Finally the proposed method is applied to the identification and contribution of noise sources caused by the GDI components of the test engine.

• Nuclear Engineering and Technology
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• 제37권5호
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• pp.503-510
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• 2005

An instrumental neutron activation analysis was used to measure the concentrations of about 24 elements associated with airborne particulates (PM10) that were collected in the most polluted urban region of Daejeon city, Korea from 2000 to 2002. Using the measurement data for various elements, both the extent of elemental pollution in the study area and the seasonality in their distribution characteristics were examined. Examinations of their distribution patterns indicated that most elements with crustal origin tend to exhibit seasonal peaks during spring, while most elements with anthropogenic origin tend to exhibit seasonal peaks during fall or winter. In order to explain the factors regulating their mobilization properties, the data were processed by a factor analysis. Results of the factor analysis suggested competing roles of both industrial and natural source processes, despite that the study site is located at a downwind position of the industrial complex. Based on the overall results of this study, it is concluded that the site may be strongly impacted by man-made sources but the general patterns of elemental distributions in the study area inspected over a seasonal scale are quite consistent with those typically observed from natural environment.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.184-187
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• 2006

The radiometric correction is prerequisite to derive both land and ocean surface properties from optical remote sensing data. Radiometric calibration of remotely sensed data has traditionally been accomplished by means of vicarious ground calibration techniques. The purpose of this study is to calibrate the radiometric characteristic of Airborne Multispectral Scanner (AMS) by field campaign. In order to calibrate the AMS data, four different spectral tarps which are 3.5%, 23%, 35%, and 53% were validated by GER-3700 that is the surface reflectance measurement equipment and were utilized. After validation of the spectral tarps, each reflectance from the spectral tarps was compared with Digital Number (DN) value of AMS. There was very high correlation between tarp reflectance and DN value of AMS so that radiometric calibration of AMS data has been accomplished by those results. The calibrated AMS data were validated with in-situ measured reflectance data from artificial and natural target. Also QuickBird image data were used for verifying the results of AMS radiometric calibration. This presentation discusses the results of the above tests.

• 한국산업보건학회지
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• 제30권2호
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• pp.174-184
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• 2020

Objectives: The purpose of this study was to improve the working environment by identifying the work satisfaction of the cleaning workers of the aircraft and measuring and assessing the harmful factors of the cleaning process. Methods: We asked 23 cleaning companies for questionnaires and got 100 answers from 5 companies. The A-E Airline health manager has been contacted to establish a site survey schedule. The in-flight and lounge were measured using direct reading equipment. The harmful factor to be measured are noise, dust, temperature, volatile organic compound, total airborne bacteria, and total airborne bacteria. Results: Uncomfortable positions when replacing blanket, cleaning the table, and cleaning the floor have been identified as factor that reduce work satisfaction. Noise when replacing newspapers and cleaning toilets has been identified as a factor that lowers work satisfaction. Temperature and humidity were found to reduce work satisfaction during in-flight disinfection. Measurements of aircraft cabin and lounge with direct read equipment have shown that none of the items exceed the exposure criteria. Conclusions: As a result of measuring direct-reading equipment, no items exceeded the exposure criteria for each harmful factor. A clear survey of the working environment is required based on the results, and additional research is needed using personal sample measurement.

• 한국입자에어로졸학회지
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• 제10권2호
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• pp.83-91
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• 2014

Since airborne bacteria have been known to aggravate indoor air quality, studies on reducing bacteria particles increase recently. In this study, a chamber(0.8m x 0.8m x 1.56m) system was built in order to simulate real conditions for reducing airborne bacteria, and evaluated by a simple aerosol reduction test. A method utilizing CFD(Computational Fluid Dynamics) simulation was used to detect the horizontal cross-sectional area which represents particle distribution in the chamber. Then an air-cleaner with HEPA filter and Carbon Fiber Ionizer was located on that area for aerosol reduction test. The CFD result found the area was located at 0.2m height from the bottom of the chamber, and the test showed aerosol reduction efficiencies using measurements of number concentration and CFU(colony forming unit) per each case. At the measurement of number concentration, the reduction efficiency of air-cleaner with filter and ionizer(Case 3) was about 90% after 4 minutes from the stop of the bacteria injection, and that with only filter(Case 2) was about 90% after 8 minutes from the beginning. Lastly, that without filter and ionizer(Case 1) was about 30% after 10 minutes. At the measurement of CFU, it shows similar results but it is related to viability of bio-aerosol.

• Journal of Radiation Protection and Research
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• 제2권1호
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• pp.9-16
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• 1977

공기부유진내(空氣浮游塵內)에 존재(存在)하는 라돈 붕괴생성물(崩壞生成物) 즉(卽) RaA, RaB및 RaC의 간단(簡單)한 농도측정법(濃度測定法)을 확립(確立)하였다. 이것은 단일집진장치(單一集塵裝置)로 membrane 여과지(濾過紙)(평균(平均) pore size=$0.8{\mu}m$)에 채취(採取)한 시료(試料)의 전(全)알파 방사능(放射能)을 시차별(時差別)로 측정(測定)하므로서 농도(濃度)를 결정(決定)하는 방법(方法)이다. 일연(一聯)의 예비실험(豫備實驗)으로써 이 방법(方法)을 이용(利用)하여 한국원자력연구소(韓國原子力硏究所) 구내(構內)에서 라돈 붕괴생성물(崩壞生成物)의 시간적(時間的) 농도변화(濃度變化)를 측정(測定)하였다. 이들 농도(濃度)의 시간적(時間的) 변화(變化)는 심(甚)하였는데 대개(大槪)의 경우(境遇) 최고치(最高値)는 대기(大氣)의 밀도(密度)가 비교적(比較的) 높은 아침에 나타났고 최고치(最高値)는 기(其) 반대(反對)인 오후(午後)에 나타났다.