• 상하수도학회지
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• 제11권1호
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• pp.109-118
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• 1997

In this study, we examined the structural analysis of water demand fluctuation for water distribution control of water supply network. In order to analyze for the length of stationary time series, we calculate autocorrelation coefficient of each case equally divided data size. As a result, it was found that, with the data size of around three months, any case could be used as stationary time series. we analyze cross-correlation coefficient between the daily water consumption's data and primary influence factors. As a result, we have decided to use weather conditions and maximum temperature as natural primary factors and holidays as a social factor. Applying the multiple ARIMA model, we obtains an effective model to describe the daily water demand prediction. From the forecasting result, even though we forecast water distribution quantity of the following year, estimated values well express the flctuations of measurements. Thus, the suitability of the model for practical use can be confirmed. When this model is used for practical water distribution control, water distribution quantity for the following day should be found by inputting maximum temperature and weather conditions obtained from weather forecast, and water purification plants and service reservoirs should be operated based on this information while operation of pumps and valves should be set up. Consequently, we will be able to devise a rational water management system.

• 대기
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• 제24권4호
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• pp.471-479
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• 2014

A road surface temperature prediction model (UM-Road) using input data of the Unified Model (UM) output and road physical properties is developed and verified with the use of the observed data at road weather information system. The UM outputs of air temperature, relative humidity, wind speed, downward shortwave radiation, net longwave radiation, precipitation and the road properties such as slope angles, albedo, thermal conductivity, heat capacity at maximum 7 depth are used. The net radiation is computed by a surface radiation energy balance, the ground heat flux at surface is estimated by a surface energy balance based on the Monin-Obukhov similarity, the ground heat transfer process is applied to predict the road surface temperature. If the observed road surface temperature exists, the simulated road surface temperature is corrected by mean bias during the last 24 hours. The developed UM-Road is verified using the observed data at road side for the period from 21 to 31 March 2013. It is found that the UM-Road simulates the diurnal trend and peak values of road surface temperature very well and the 50% (90%) of temperature difference lies within ${\pm}1.5^{\circ}C$ (${\pm}2.5^{\circ}C$) except for precipitation case.

• 풍력에너지저널
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• 제14권3호
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• pp.61-68
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• 2023

This paper aims to perform optimal operation and maintenance with an integrated monitoring system for offshore wind platforms. Based on the wind direction and wind speed data of existing wind farms, a monitoring system was established along with weather and weather data to maximize the operational efficiency of wind farms. Compared to wind power on land, offshore wind power is difficult to maintain due to weather, logistics and geographical limitations. Therefore, economic analysis of actual operation and maintenance is essential for large-scale offshore wind farms. In this paper, the availability of offshore wind farms was analyzed by using personnel resources, parts inventory, Crew Transfer Vessel (CTV) and Specialized service Operation Vessel (SOV) etc. before the actual operation and maintenance of wind farms. A comparative analysis was conducted to determine the optimum operating efficiency and economical maintenance costs.

• 풍력에너지저널
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• 제14권3호
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• pp.25-33
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• 2023

In order to secure the safety of increasing offshore activities such as offshore wind farm maintenance and fishing, IMPACT, a mid-term marine weather forecasting system, was established by predicting marine weather up to 7 days in advance. Forecast data from the Korea Hydrographic and Oceanographic Agency (KHOA), which provides the most reliable marine meteorological service in Korea, was used, but wind speed and wave height forecast errors increased as the leading forecast period increased, so improvement of the accuracy of the model results was needed. The Model Output Statistics (MOS) method, a post-correction method using statistical machine learning, was applied to improve the prediction accuracy of wave height, which is an important factor in forecasting the risk of marine activities. Compared with the observed data, the wave height prediction results by the model before correction for 6 to 7 days ahead showed an RMSE of 0.692 m and R of 0.591, and there was a tendency to underestimate high waves. After correction with the MOS technique, RMSE was 0.554 m and R was 0.732, confirming that accuracy was significantly improved.

• 디지털콘텐츠학회 논문지
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• 제13권4호
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• pp.539-545
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• 2012

디지털방송은 기존 영상중심의 방송프로그램 외에 게임, 날씨, 증권, 공공서비스 등의 다양한 데이터 서비스 (응용 소프트웨어)를 시청자에게 제공하는 멀티 서비스 플랫폼으로 발전하고 있다. 하지만 현재까지 데이터 서비스는 인지도를 높일 킬러 서비스의 부재와 방송프로그램 간 연동성의 미흡함으로 인해 시청자로부터 만족할만한 관심을 받지 못하고 있다. 이 에, 본 논문은 데이터 서비스와 방송프로그램 간의 상호 시너지 효과를 높이기 위해선 미들웨어들이 제공하는 데이터 서비스의 생명주기를 방송프로그램 방송시간으로 한정하는 물리적 연동 개념만으론 부족하다고 판단하고 방송프로그램의 내용을 기반으로 데이터 서비스가 방송프로그램과 의미적으로 연동할 수 있는 방법을 소개한다.

• 대한지구과학교육학회지
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• 제14권3호
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• pp.257-266
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• 2021

본 연구에서는 2009 개정 및 2015 개정 초등 과학교과서에 제시된 5학년 '날씨와 우리생활' 단원의 탐구 중 '안개 실험'과 관련하여 예비교사들의 이해를 알아보았다. 연구 대상은 교육대학교 학생 100명으로 초등과학교재연구 강의에 참여한 학생들이다. 예비교사들은 두 교육과정에 대해 사전학습 후, 실험을 비교수행하고 논의하는 자율적인 교재연구를 하였다. 그 후 예비교사들이 개별적으로 답한 결과와 과제를 분석한 결과는 다음과 같다. 첫째, 2009 개정과 2015 개정 교육과정에서의 안개 발생 차이를 응결, 수증기 등의 관련 과학적 개념으로 설명한 예비교사는 24명(24%)이었고 그중 1명(1%)만이 포화개념을 이용하여 설명하고 있었다. 둘째, 교육과정 변화에 따른 안개실험 방법의 변화에 대해 그 이유를 알아낸 예비교사들은 48명(48%)이었다. 셋째, 예비교사들은 과학적 지식의 중요성보다는 실험의 재현과 성공을 중요시하였으며, 그런 예비교사들은 대체실험이나 동영상 자료 활용을 제안하였다.

• Wind and Structures
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• 제12권4호
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• pp.349-381
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• 2009

Since 1998, several institutions have deployed mobile instrumented towers to collect research-grade meteorological data from landfalling tropical cyclones. This study examines the wind flow characteristics from seven landfalling tropical cyclones using data collected from eight individual mobile tower deployments which occurred from 1998-2005. Gust factor, turbulence intensity, and integral scale statistics are inspected relative to changing surface roughness, mean wind speed and storm-relative position. Radar data, acquired from the National Weather Service (NWS) Weather Surveillance Radar - 1988 Doppler (WSR-88D) network, are examined to explore potential relationships with respect to radar reflectivity and precipitation structure (convective versus stratiform). The results indicate tropical cyclone wind flow characteristics are strongly influenced by the surrounding surface roughness (i.e., exposure) at each observation site, but some secondary storm dependencies are also documented.

• 한국멀티미디어학회논문지
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• 제18권6호
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• pp.772-779
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• 2015

Advancing information technology have rapidly changed our service environment of life, culture, and industry. Computer information communication system is applied in medical, health, distribution, and business transaction. Smart is using new information by combining ability of computer and information. Although agriculture is labor intensive industry that requires a lot of hands, agriculture is becoming knowledge-based industry today. In agriculture field, computer communication system is applied on facilities farming and machinery Agricultural. In this paper, we designed and implemented application that provides personalized agriculture related information at the actual farming field. Also, this provides farmer a system that they can directly auction or sell their produced crops. We designed and implemented a system that parsing information of each seasonal, weather condition, market price, region based, crop, and disease and insects through individual setup on ubiquitous environment using location-based sensor network and processing data.

• 플랜트 저널
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• 제7권1호
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• pp.40-48
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• 2011

This study shows the comparison between expected and actual capacity factors of a wind farm through wind resource analyzation. The expected capacity factor comes from an 'automatic weather system' run by the Korean national weather service and a 'meteorological mast' run by a project owner. Based on this comparison and analysis, the importance of meteorological mast micro-siting and selection of wind turbine class and type, will be studied along with presenting important implications for wind farm expansion and development.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2014년도 제49차 동계학술대회논문집 22권1호
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• pp.29-30
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• 2014

최근 해양 분야에서는 레저보트, 윈드서핑, 낚시 해상관광 등 해상에서 활동이 증가됨에 따라 선박의 안전을 비롯하여 해상 활동을 위한 다양한 정보 제공 요구가 점차 늘어가고 있다. 해상활동을 위한 정보제공은 사용자의 위치를 기반으로 사용자에게 적합한 정보의 제공이 필요하다. 특히, 전자해도 상에 사용자의 위치 또는 사용자가 지정한 위치를 기반으로 정보를 제공하는 위치 기반 정보 서비스의 제공 요구가 늘어나고 있다. 본 논문에서는 사용자의 위치 또는 사용자가 설정한 위치를 중심으로 전자해도 상에 정보를 표시하여 제공하는 정보시스템 모델을 제시한다. 본 논문에서 제시하는 시스템은 사용자 디바이스로부터 획득한 위치정보 또는 사용자가 전자해도 상에 지정한 위치를 바탕으로 항로표지 정보, 일출, 일몰, 간조, 만조, 날씨 등을 표시하여 제공한다.