• 한국ITS학회:학술대회논문집
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• 2002.11a
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• pp.67-71
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• 2002

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.58-59
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• 2000

오존은 공간적.시간적 변동이 매우 큰 대기오염물질로 서울시의 27개 대기오염 자동측정망에서 실시간으로 측정.감시되고 있으며, 오존의 농도가 높아지는 여름철에는 오존경보제를 실시하고 있다. 특히 오존의 농도는 일사, 풍향, 풍속 등의 기상인자, $NO_x$, VOCs 등 전구물질의 농도, 그리고 지형에 따라서 영향을 받는 것으로 알려져 있다. 따라서, 본 연구에서는 서울지역에 대한 기하학적 축소모형을 제작하여 풍동내에서 풍향.풍속을 측정하여 지형에 따른 바람의 특성을 파악하였다. (중략)

• Journal of Korean Society for Atmospheric Environment
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• v.10 no.E
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• pp.357-370
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• 1994

This paper introduces an Eulerian long- range transport model coupled with a mesoscale atmospheric model. The model has been applied to the simulation of tracer distribution during two cases of Cross Appalachian Tracer Experiment (CAPIEX). Meteorological fields are Predicted by CSU RAMS with four-dimensional assimilation and tracer transport is computed from an Eulerian dispersion model. The atmospheric model with a four-dimensional assimilation has produced meteorological fields that agree well with observation and has proved its high potential as a generator of meteorological data for a long-range transport model. The Present transport model Produces reasonable simulations of observed tracer transport although it was partially successful in the case with complicated structure in observed concentration. Model with Bott's 2nd-order scheme performs as well as that with Bott's 4th-order scheme and increased explicit horizontal diffusivity. Diagnosis of the model results indicates that the Present long-range transport model has a good potential as a framework for the acid deposition model with detailed cloud and chemical processes.

• The Korean Journal of Applied Statistics
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• v.30 no.6
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• pp.1005-1013
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• 2017

In this paper, we investigate the performances of time series models to forecast irradiance that consider weather variables such as temperature, humidity, cloud cover and Global Horizontal Irradiance. We first introduce the time series models and show that regression ARIMAX has the best performance with other models such as ARIMA and multiple regression models.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.2
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• pp.151-158
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• 2000

Since Pusan metropolitanarea where is composed complex terrain is connected to sea the sea-land breeze circulation and the mountain-valley circulation are apt to form A regional scale circulation system is formed at a region which has complex terrain because of curves of its and affect to the dispersion and advection of air pollutants. LCM Local Circulation Model which a propriety was verified described that sea breeze and valley wind at the daytime and land breeze and mountain wind at the nighttime were well devellped over the Pusan metropolital area. Next for the investigation of accuracy of simulated results an observed value at Kae-Kum and Su-Young on the pusan metropolitan area were compared with it at those points. From the comparison of the temperature and horizontal velocity between the results of LCM and an observed values they have a similar trend of a diurnal variation. For the prediction of dispersion and transportation of air pollutants the wind field should be calculated with high accuracy. A numerical simulation using LCM can provide more accuracy results around Pusan metropolitan area.

• Journal of Environmental Science International
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• v.19 no.1
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• pp.27-37
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• 2010

A system coupled the prognostic WRF mesoscale model and CALMET diagnostic model has been employed for predicting high-resolution wind field over complex coastal area. WRF has three nested grids down to from during two days from 24 August 2007 to 26 August 2007. CALMET simulation is performed using both initial meteorological field from WRF coarsest results and surface boundary condition that is Shuttle Radar Topography Mission (SRTM) 90m topography and Environmental Geographic Information System (EGIS) 30m landuse during same periods above. Four Automatic Weather System (AWS) and a Sonic Detection And Ranging (SODAR) are used to verify modeled wind fields. Horizontal wind fields in CM_100m is not only more complex but better simulated than WRF_1km results at Backwoon and Geumho in which there are shown stagnation, blocking effects and orographically driven winds. Being increased in horizontal grid spacing, CM_100m is well matched with vertically wind profile compared SODAR. This also mentions the importance of high-resolution surface boundary conditions when horizontal grid spacing is increased to produce detailed wind fields over complex terrain features.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.3
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• pp.309-323
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• 2006

We focus on the improvement in the simulation of sea surface wind over complex coastal area located in the southeastern Korea. In this study, it was carried out sensitivity experiment based on PBL schemes and dynamic frame of MM5 and WRF. Two widely used PBL parameterization schemes were chosen : Medium-Range Forecast (MRF) and Mellor-Yamada-Janjic (MYJ). Thereafter, two cases of sea fog days with weak wind speed and typhoon days with strong wind speed were simulated and analyzed. The result of experiments indicated that wind fold of WRF model was shown more similar distribution with observational data, compared with that of MM5. Simulation of sea surface wind during sea fog days with weak wind speed and typhoon days with strong wind speed were shown similar horizontal distribution with observational data using MYJ and MRF PBL schemes of WRF model, respectively. Horizontal distribution of sea surface wind was more sensitive according to dynamic frame and PBL Schemes of model during sea fog days and typhoon days, respectively.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.6 no.2
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• pp.45-56
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• 2007

As function and scale of the transit center get larger, the efficient guidance system in the transit center is essential for transit users in order to find their efficient routes. Although there are several studies concerning optimal path for the road, but insufficient studies are executed about optimal path inside the building. Thus, this study is to develop the algorithm about optimal path for car owner from the basement parking lot to user's destination in the transfer station. Based on Dijkstra algorithm which calculate horizontal distance, several factors such as fatigue, freshness, preference, and required time in using moving devices are objectively computed through rank-sum and arithmetic-sum method. Moreover, optimal public transportation is provided for transferrer in the transfer station by Neuro-Fuzzy model which is reflected on people's tendency about public transportation mode choice. Lastly, some scenarios demonstrate the efficiency of optimal path algorithm for pedestrian in this study. As a result of verification the case through the model developed in this study is 75 % more effective in the scenario reflected on different vertical distance, and $24.5\;{\sim}\;107.7\;%$ more effective in the scenario considering different horizontal distance, respectively.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.3
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• pp.246-260
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• 2014

A 90-m horizontal-resolution numerical model was configured to study the micrometeorological features of local winds in the valley of Gwangneung KoFlux (Korea Flux network) Sites (GDK: Gwangneung Deciduous forest site in Korea, GCK: Gwangneung Coniferous forest site in Korea) during summer days. The U. S. Geological Survey (USGS) Shuttle Radar Topography Mission (SRTM) data were employed for high-resolution model terrain height. Model performance was evaluated by comparing observed and simulated near-surface temperature and winds. Detailed qualitative analysis of the model-simulated wind field was carried out for two selected cases which are a clear day (Case I) and a cloudy day (Case II). Observed winds exhibited that GDK and GCK, as well as Case I and Case II, had differences in timing, duration and strength of daytime and nighttime wind direction and speeds. The model simulation results strongly supported the existence of the drainage flow in the valley of the KoFlux tower sites. Overall, the simulated model fields realistically presented the diurnal cycle of local winds in and around the valley, including the morning drainage-upslope transition and the evening reversal of upslope wind. Also, they indicated the complexity of local winds interactions by presenting that daytime westerly winds in the valley were not always pure mountain winds and were often coupled with larger-scale wind systems, such as synoptic-scale winds or mesoscale sea breezes blowing from the west coast of the peninsula.

• International Journal of Highway Engineering
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• v.11 no.3
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• pp.129-139
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• 2009

The transportation network is a critical infrastructure in the event of natural and human caused disasters such as rainfall, snowfall, and terror and so on. Particularly, the transportation network in an urban area where a large number of population live is subject to be negatively affected from such events. Therefore, efficient traffic operation plans are required to assist rapid evacuation and effective detour of vehicles on the network as soon as possible. Recently, ubiquitous communication and sensor network technology is very useful to improve data collection and connection related emergency information. In this study, we develop a specific algorithm to provide evacuation route and detour information only for vehicles under emergency situations. Our algorithm is based on shortest path search technique and dynamic traffic assignment. We perform the case study to evaluate model performance applying hypothetical scenarios involved terror. Results show that the model successfully describe effective path for each vehicle under emergency situation.