• Journal of applied mathematics & informatics
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• v.9 no.2
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• pp.771-785
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• 2002

Many industries like energy, utilities, ice cream and leisure sports are closely related to the weather. In order to hedge weather related risks, they invest their assets with portfolios like option, coupons, future, and other weather derivatives. Among weather related derivatives, CDD and HDD index options are mainly transacted between companies. In this paper, the autocorrelation system of temperature will be checked for several cities in Korea and the parameter estimation will be carried based on the maximum likelihood estimation. Since the log likelihood increase as the number of parameters increases, we adopt the Schwarz information criterion .

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.5
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• pp.857-862
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• 2017

The management of the electric power facilities became important in accordance with the industrial development and electric power facilities were influenced by weather. Even if the same kind of electric power facilities is estimated for extracting the time-varying failure rate, the failure rate could be different depending on external effect such as climate. This research will show the data mining modeling of the weather-related outage and influence of weather on the electric power facility with recent data.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.6
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• pp.31-40
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• 1997

Potential impacts for unfavourable weather conditions and the assessment of the magnitudes of their adverse effects on crop yields were studied. EPIC model was investigated for its capability on crop yield predictions for rice and soybean. Weather generationmodel was used to generate long-term climatic data. The model was verified with ohserved climate data of Suwon city. Fifty years weather data including abnormal conditions were generated and used for crop yield simulation by EPIC model. Crop yield probability function was derived from simulated crop yield data, which followed normal distribution. Probable crop yield reductions due to abnormal weather conditions were also analyzed.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.235-237
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• 2005

This paper presents a method of incorporating weather effects in KEPCO systems reliability evaluation. The effects of adverse weather on composite power system FOR(Forced Outage Rate) increase considerably as the proportion of outages in adverse weather increases. It is therefore important to establish suitable and practical procedures for collecting adverse weather data which can be utilized in realistic KEPCO systems reliability assessment. The modeling procedure proposed in this paper also provides a realistic FOR in KEPCO systems using real historical data.

• The Bulletin of The Korean Astronomical Society
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• v.32 no.1
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• pp.24.2-24.2
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• 2007

• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05a
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• pp.95-97
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• 2010

This study revealed unusual weather phenomena by comparing and analyzing monthly average temperature and amount of snowfall for the past 10 years, and, based on the weather phenomena, analyzed damage cases of concrete structures in winter. As a result, the temperature for the recent one year became greatly low compared with the monthly average for the past 10 years, and the snowfall increased by 4-5 times compared with the past, so that the frost damage of concrete structures also greatly occurred. Accordingly, in case of concrete construction, because there may occur various variables owing to abnormal weather conditions, it is required that thorough quality control should be performed even from the stage of construction plan, execution and maintenance.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.261-264
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• 2003

Cold weather can lead to many problems in mixing, placing, setting time, and curing of concrete that can have harmful effects on its properties and service life. Korean Concrete Institute (KCI) defines cold weather as a period when the average daily air temperature is less $4^{\circ}C$ and recommends to cast concrete with special care such as shielding, heating and so on. The use of high early strength cements may improve the rate of hardening characteristics of concrete in cold weather by making it possible to achieve faster setting time and evolving more hydration heat than ordinary Portland cement. Higher early strength can be achieved using Type III cement especially during the first 7 days. The strength increase property of Type III cement at low temperature was studied. As a conclusion the heat or heat insulation curing period can be reduced to 50~75%. So, it can be used for cold weather concreting to reduce construction cost and extend the construction season.

• Aerospace Engineering and Technology
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• v.3 no.2
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• pp.133-140
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• 2004

In some cases, the launch vehicle is fatally affected by the change of weather condition. Thus the real time monitoring of weather condition is indispensible for successful launch campaign. This paper described general characteristics of weather radar for space center. The analysis of weather radar requirements has been carried out focusing on the transmitting power, gain of antenna, half power beam width, and minimum detectable signal.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.2014-2020
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• 2010

This paper aims to find out characteristics of railroad weather-related accidents and incidents and to proposes the plan of railroad disaster prevention according to the precipitation. For this, we make the database about the railroad weather-related accidents and incidents and analysis the relationship between the hourly and cumulative precipitation and railroad accidents. The results are as follows; The weather events that have the most occurrence frequency of railroad weather-related accidents and incidents is a rainfall of the precipitation and then the cause of that was the falling rocks and the collapsed roadbed. The rainfall patterns of collapsed roadbed were classified into 4 groups. When the variation of hourly rainfall is 10/15 mm/hr over, we need to consider the caution/stop of train operation and a speed limit, respectively.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.04a
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• pp.408-413
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• 1996

The purpose of this study is to present the reference data about the period in cold weather concrete practice based on meteorological data of Korea meteorological administration in our country in comparison with previous study and specifications of foreign country as to cold weather concrete such as ACI, JASS-5 and JSCE. The results of this study indicate that the period of cold weather concrete by each specifications in most of the region except Cheju island and coastal region in Korea is lasted over 100 days and the period of cold weather concrete in hillsides and inland areas is longer than that of coastal regions in the same latitude.