• Title/Summary/Keyword: AIR 모델

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Implementation of Airborne Multi-Function Radar Including Attitude Maneuvering (자세 기동을 고려한 항공기 탑재 다기능 레이다 통합 시뮬레이터 구현)

  • Ko, Jae-Youl;Park, Soon-Seo;Choi, Han-Lim;Ahn, Jae-Myung;Lee, Sung-Won;Lee, Dong-Hui;Yoon, Jung-Suk
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.28 no.3
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    • pp.225-236
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    • 2017
  • In this paper, a simulation test bed is presented which operates to provide full-scale simulation of airborne multi-function phased array radars. This simulation test bed provides a capability to evaluate the target tracking performance. To realize aircraft operation scenario, we developed 6DOF aircraft dynamics model which can generate trajectories and attitude of an aircraft. This procedure includes steady state flight trim search, autopilot design, and aircraft guidance command design. Also, the radar-environment integrated simulator includes target detection/measurement model and tracking filter. Developed simulator is validated by creating an air-to-air scenario.

Pollutant Sources Contribution Analysis of PM2.5 using The CMB Receptor Model (CMB 수용모델을 이용한 PM2.5의 오염원 기여도 분석)

  • Koo, Tai-Wan;Hong, Min-Sun;Moon, Su-Ho;Kim, Ho-Jung
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.3
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    • pp.866-875
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    • 2019
  • In this study, The Chemical Mass Balance (CMB) model was used to identify pollutant sources and their contributions to $PM_{2.5}$. The contribution rankings by emission source in A city were ash dust (30.1%) > biomass burning (21.9%) > secondary pollutants (21.1%) > mobile source (19.3%) > area sources (7.6%), and The emission sources increased from the contribution of the CMB model and the Clean Air Policy Support System (CAPSS) emissions were biomass burning and secondary pollutants, and The emission sources reduced were mobile source, ash dust, and area sources.

Prediction of Flow Pattern inside a Power Condenser by Computer Modelling (전산모델에 의한 응축기내에서의 기체유동현상의 예측)

  • Seoul, Kwang Won;Lee, Sang Yong
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.17 no.3
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    • pp.238-248
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    • 1988
  • The flow pattern inside the power condenser is generally known to be very complicated due to the phase change and turbulence effects as well as the effect of condenser geometry. In the present study, the flow pattern inside the power condenser was numerically simulated with a personal computer. The widely known CHAMPION 2/E/FIX(Concentration, Heat and Momentum Program Instruction Outfit, 2D/Elliptic/Fixed grid) computer code was modified for this purpose. The flow was asssumed to be two-dimensional and steady-state, and the tube bank was considered to be homogeneous porous medium. Simple turbulent diffusion coefficients based on the appropriate experiments were obtained for the computation. Through this analytical approach, the flow pattern could be predicted fairly well. The computational results also show that the location of the air vent plays an important key role in determining the efficiency of the condenser.

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Simulation of the Kitchen and Bathroom Exhaust Systems in High-Rise Apartment Buildings (고층 아파트의 주방 및 욕실 배기 시스템 시뮬레이션)

  • 김영돈;김광우
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.15 no.12
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    • pp.996-1006
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    • 2003
  • The objective of this study is to find major variables which influence the performance of kitchen and bathroom exhaust systems in high-rise apartment buildings. For this purpose, the influencing factors on the exhaust airflow rates from the kitchen or bathroom are identified and in every cases, which are made of combinations between the influencing factors, the exhaust airflow rates are calculated through the simulations. The results of the simulation show that the exhaust airflow rates from the kitchen and bathroom mainly depends on outdoor air temperature, number of floors, airtightness of the building envelope, fan on ratio, vertically connected to same shaft, exhaust fan capacity for kitchen or bathroom, roof ventilator capacity and shaft area for kitchen or bathroom exhaust.

Fan Noise Prediction Method of Air Conditioning and Cooling System (공기조화 및 냉각시스템의 팬 소음예측 기법)

  • Lee, Jin-Young;Lee, Chan;Kil, Hyun-Gwon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.11a
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    • pp.1318-1320
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    • 2007
  • Fan noise prediction method is presented for air conditioning and/or cooling system applications where fan acts as an internal equipment having very complicated flow interaction with other various system components. The internal flow paths and distribution in the fan-applied systems such as computer or air conditioner are analyzed by using the FNM(Flow Network Modeling) with the flow resistances for flow elements of the system. Based on the fan operation point predicted from the FNM analysis results, the present fan noise model predicts overall sound power, pressure levels and spectrum. The predictions of the flow distribution, the fan operation and the noise level in electronic system by the present method are well agreed with 3-D CFD and actual noise test results.

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A Study on the Dry Deposition Model of Air Pollutants Considering Canopy Effect (Canopy를 고려한 대기오염물질의 건성침적모델에 관한 연구)

  • 이화운;박종길
    • Journal of Environmental Science International
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    • v.4 no.2
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    • pp.151-158
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    • 1995
  • A numerical model has been developed to predict the deposition of air pollutants considering canopy effect. In this model, the deposition velocity is calculated using the deposition resistances(aerodynamic resistance, viscosity resistance, surface resistance). Using the results, a comparative study was made between the model calculation and observation results. The calculated daily variation of deposition resistances and in daytime most of the model cases are well agreed with observation results, and a slight difference was found in nighttime. From the results, it is suggested that the present model is capable of estimating the deposition velocity of air Pollutants considering characteristics of canopy layer.

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Preliminary Testing of an Urban Air Quality Model for Ozone Forecasting over the Sydney Basin (시드니만의 오존예측을 위한 도시대기질모델의 예비검사)

  • Speer, Milton S.;Leslie, Lance M.
    • Journal of Environmental Science International
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    • v.13 no.8
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    • pp.733-737
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    • 2004
  • FThe aim of this study was to carry out a preliminary test of the air quality modelling system (HIRES-AIRCHEM) developed at The University of New South Wales, particularly with regard to the forecast ozone distribution. This was achieved by assimilating the New South Wales State Environment Protection Authority (EPA) emissions inventory, consisting of road and non-road sources, and running the system over the Sydney metropolitan area for the four day period 25-28 February 1998. During this period ozone readings exceeded the EPA's goal of 8pphm on several occasions. The model forecasts of ozone distribution verified well with the EPA's ozone readings. This result has important implications for possible future use of the system as a tool for routinely predicting and assessing air quality.

Comparison of Photochemical State between Polluted and Clean Air from the Monitoring Result of Trace Reactive Air Pollutant - NO, $NO_2$, $O_3$, PAN (반응성 미량 기체(NO, $NO_2$, $O_3$, PAN)의 농도 측정을 통한 오염지역과 청정지역의 광화학 상태에 대한 비교연구)

  • 김세웅;이강웅;김경렬
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 1999.10a
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    • pp.305-306
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    • 1999
  • 현재 우리나라의 가장 큰 대기오염의 문제 중 하나가 광화학 오존이라는 것은 누구나 인정하는 사실이다. 그러나 아직까지 우리나라의 광화학 오존에 대한 연구는 일반인의 관심에 비하여 많이 활성화 되지 못한 것이 현실이다(김영성 외, 1998), 또한 정부에서는 오존 경보제와 예보제를 도입 시행 중이지만 주요한 시행 정책 및 예측모델이 주로 선진국의 것을 기본으로 하고 있어 우리의 현실과의 차이가 여러차례 지적된 바 있다(김영성 외, 1998).(중략)

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Unsteady Flamelet Modeling for Flame Structure and Soot Formation of Lanimar Non-premixed CH4/Air Flame (비정상 화염편 모델을 이용한 대기압 층류 비예혼합 CH4/Air 화염장의 매연입자 생성 특성 및 화염구조 해석)

  • Kim, Taehoon;Jeon, Sangtae;Kim, Yongmo
    • 한국연소학회:학술대회논문집
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    • 2012.11a
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    • pp.137-138
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    • 2012
  • The two-equation soot model based on the transient laminar flamelet model is implemented for soot formation of laminar non-premixed $CH_4/Air$ flame with detailed chemical reaction mechanism and complex thermodynamic properties. The soot model represents nucleation, growth and oxidation with gas-phase chemistry. This represented unsteady flamelet soot model has been tested and compared using well verified reference calculation result obtained solving the Full Transport Equations method.

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The 3rd National Conference Of Professional engineers - On The Problems and Guideline of The Air Quality Model Operation (제3회 전국기술사대회 특집(환경) - 대기모델 운영의 문제점 및 가이드라인 설정방향)

  • Park, Sun-Hwan
    • Journal of the Korean Professional Engineers Association
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    • v.42 no.4
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    • pp.40-44
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    • 2009
  • The analysis of air quality model applied for EIA in Korea indicates that ISCST3 and CALINE3 dominate the model, and it causes the problem that regional and business characteristics are not taken into account. To solve this problem, it appears necessary to build guideline of the air quality model operation. First of all, to implement the above plan we need to categorize the site into simple and complex terrain, coast to consider regional characteristics, and the sources of pollutants into point/area/line as well. To make the procedure more efficient with reduced time and less cost, we are to apply screening model for prelimninary work of the suggested model.

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