• 한국전산유체공학회지
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• 제10권1호
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• pp.87-93
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• 2005

Macao, a city with three sides bounded by water, is hot and humid in weather in more than six months of a year. This uncomfortable weather induces the frequency of operating air-conditioners. Choice of location for installation of air-conditioner in a building will affect the performance of cooling effect and thermal comfort on the occupants, which in turn will affect the indoor air quality (IAQ) of the building. In the paper, investigation of distribution on carbon dioxide, room air temperature and velocity, as well as air diffusion performance index (ADPI) of a single bedroom in Macao is studied by using the computational fluid dynamics (CFD) software FLOVENT 3.2. Simulations of locating the air-conditioner at 4 different walls will be done and comparisons and analyses of the results will be performed to decide a proper location for the air-conditioner for obtaining good thermal comfort.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2004년도 한국우주과학회보 제13권1호
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• pp.38-38
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• 2004

In this talk, we present a good example of extreme solar and geomagnetic activities from October to November, 2003. These activities are characterized by very large sunspot groups, X-class solar flares, strong particle events, and huge geomagnetic storms. We discuss ground-based and space-based data in terms of space weather scales. We applied the CME propagation models to these events in order to predict the arrivals of heliospheric disturbances. (omitted)

• Spatial Information Research
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• 제21권1호
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• pp.1-13
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• 2013

This paper describes a GIS framework for geo-semantic information retrieval in mobile computing environments. We built geographic ontologies of POI (point of interest) and weather information for use in the combination of semantic, spatial, and temporal functions in a fully integrated database. We also implemented a geo-semantic app for Android-based smartphones that can extract more appropriate POIs in terms of user contexts and geographic ontologies and can visualize the POIs using Google Maps API (application programming interface). The feasibility tests showed our geo-semantic app can provide pertinent POI information according to mobile user contexts such as location, time, schedule, and weather. We can discover a baking CVS (convenience store) in the test of bakery search and can find out a drive-in theater for a not rainy day, which are good examples of the geo-semantic query using semantic, spatial, and temporal functions. As future work, we should need ontology-based inference systems and the LOD (linked open data) of various ontologies for more advanced sharing of geographic knowledge.

• 산업기술연구
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• 제29권B호
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• pp.181-186
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• 2009

The wind data measured from automated weather stations (AWS) at complex terrains in Korea was used to predict the wind velocity at nearby sites that are several kilometers away. The ten-minute averaged wind data was measured at a height of 10 meters. A commercial CFD code, WindSIM, based on the weighted averaged Navier-Stokes equation was employed. The results were compared with the data measured using meteorological masts (MM) at a height of 40 meters. The predictions using the AWS data and WindSIM showed good agreements with the measured data.

• 한국항공운항학회지
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• 제15권3호
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• pp.57-62
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• 2007

In this paper, we attempted to produce the cloud forecast that use the numerical weather prediction(NWP) MM5 for objective cloud forecast. We presented two methods for cloud forecast. One of them used total cloud mixing ratio registered to sum(synthesis) of cloud-water and cloud-ice grain mixing ratio those are variables related to cloud among NWP result data and the other method that used relative humidity. An experiment was carried out period from 23th to 24th July 2004. According to the sequence of comparing the derived cloud forecast data with the observed value, it was indicated that both of those have a practical use possibility as cloud forecast method. Specially in this Case study, cloud forecast method that use total cloud mixing ratio indicated good forecast availability to forecast of the low level clouds as well as middle and high level clouds.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 동계학술발표대회 논문집
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• pp.205-210
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• 2005

Ice storage system stores cold energy using ice, which is used for cooling on next day. Ice storage system is the effective cooling system that uses cheep electric energy during a night, and also suppresses the peak load of electricity. In this study, the normalized temperature, relative humidity and specific humidity are analyzed using the weather data for past five years in order to estimate the cooling load for the control of ice storage system. The calculated cooling loads show fairly good agreement with the measured data of model hospital, especially at the outdoor design temperature of $25^{\circ}C$.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1360-1363
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• 1994

Epoxy resin insulator have good electrical properties (high electric strength, high resistivity, low dielectric loss) in addition to high mechanical strength, small dimensions and design versatility. Polymer insulator, however, are subjected to aging processes, caused by the surrounding atmosphere, which may lead to degradation of their properties. This paper describes the results of a important study on the artificial pollution test, Weather-Ometer properties and rotating wheel dip test of high voltage different aging insulators which are the most important factors for outdoor uses. Also, the objects of this paper are to (a)result of insulator under dry(wet) flashover voltage, (b)artificial pollution test of salt spay, (c)Accelerated aging test of Weather-Ometer, (d) wet and dry flashover voltage under rotating wheel dip test.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.402-404
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• 2000

The FRP pole had great advantages over other material poles. Light weight, easy installing and transporting were good characteristics. The material's superior properties represented the good durability for sea weather and air pollution, good insulation for electric, and changeable colors. In those properties, usages were like a area affected by sea, downtown, the area among the mountains and a special area for the outstanding views. It was studied that pole manufacturing method, structure analysis of pole by FEM in this study. Filament winding method was selected for a new pole manufacturing method. It produced the tapered poles and mechanically strong properties.

• 한국측량학회지
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• 제35권6호
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• pp.471-484
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• 2017

GNSS 가강수량은 태풍이나 집중호우의 일기예보를 위한 중요한 요소로 인식되고 있으며, 가강수량을 수치예보 모델에 초기 입력값으로 적용하여 일기예보가 향상되는 연구가 국내${\cdot}$외로 발표되고 있다. 호우 관련 일기예보를 위해서는 가강수량이 실시간 또는 준실시간으로 제공되어야 하며 가강수량 자료의 정밀함과 무결성이 유지되어야 한다. 본 논문에서는 정밀절대측위를 이용한 준실시간 가강수량 산출 시스템 개발 과정에 대해 제시하였다. 이를 위하여 정밀절대측위의 대류권 지연 추정과 관련된 변수를 최적화하고 준실시간 GNSS 가강수량 시스템을 개발하였다. 시스템의 분석을 위해 정밀절대측위와 상대측위의 준실시간 가강수량 정밀도를 비교하였다. 비교결과 정밀절대 측위의 가강수량 정밀도가 상대측위 보다 낮게 산출되었지만 자료의 무결성 부분에서는 좋은 결과가 도출되었다. 향후에는 정밀절대측위 방식의 가강수량 정밀도를 높이는 연구가 필요할 것이다.

• 한국멀티미디어학회논문지
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• 제17권2호
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• pp.143-151
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• 2014

악천후로 인하여 화질이 저하된 영상은 사물의 경계에 해당하는 에지 부분이 흐려진다. 본 논문에서는 에지를 최대한으로 선명하게 하여 영상의 시인성을 향상 시키는 화질 개선 방법을 제안한다. 우선 영상의 밝기 필드에서 극점들을 찾아 에지 후보 영역으로 선택하고, 선택된 에지의 측면에 있는 화소들의 밝기로 히스토그램을 형성한다. 형성된 히스토그램의 극소점을 기반으로 히스토그램을 다수의 모드로 분해한다. 모드가 구해지면, 영상 필드에서 에지에 의하여 연결된 모드들을 구하고, 연결된 모드들의 연결 고리를 구한다. 최종적으로 가장 긴 연결 고리를 형성하는 모드간의 간격을 최대한으로 벌린다. 이 때 최소 밝기 모드와 최대 밝기 모드는 화소 밝기 범위 이내에 있어야 한다. 이와 같이 모드의 간격을 벌림으로써 에지를 선명하게 하고 영상의 시인성을 향상한다. 본 논문에서 제안한 방법은 적은 연산량으로 기존의 방법만큼 좋은 성능으로 화질을 개선함을 보여준다.