• Journal of Information Management
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• v.42 no.2
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• pp.103-120
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• 2011

The astronomical data obtained by observations of celestial objects movements are useful in our daily life. These data - such as 1) sunrise and sunset data, 2) data transformation between lunar calendar and solar calendar, 3) solar eclipse and lunar eclipse data, and 4) sun's altitude and azimuth data - were used to important things in the agricultural society and ancient kingdom. In the modern society, these data have been used continuously for the legal disputes, construction of buildings and the other areas. This is a good example of pure science data using directly in our life. However there are difficulties to public service because all the data were printed as an Almanac. Using MySQL, we constructed web-based service system which makes to use them easily. This database system was made for the quick search using the calculated orbital data of celestial bodies.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.51.2-51.2
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• 2016

이 연구에서는 중수대명력(重修大明曆)에서 태양과 달의 운동 계산 방법에 대해 분석하였다. 중수대명력은 금(金)대의 양급(楊級)이 만든 대명력을 당대의 조지미(趙知微)가 중수한 역법으로 1281년 수시력(授時曆)이 도입되기 전까지 원(元)에서 사용되었다. 반면 조선에서는 "칠정산내편", "칠정산외편"과 더불어 일 월식 계산에 사용된 것으로 알려져 있다. 이를 위해 세종 26년(1444)에는 이순지(李純之) 등에 의해 "중수대명력"과 "중수대명력 정묘년 교식가령(丁卯年 交食假令)" 등이 편찬되었으며, "중수대명력"의 경우 "금사(金史)" 의 내용과 동일한 것으로 알려져 있다. 이 논문에서는 이들 문헌을 활용하여 중수대명력에서의 태양과 달의 운동, 특히 이들의 부등속운동 계산방법에 대해 분석하고, 이를 수시력에서의 방법과 비교 하였다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.5
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• pp.501-506
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• 2015

This study seeks to analyze ships traffic characteristics according to water time in order to provide the necessary data for efficient traffic management development. To analyze maritime traffic volume according to water time, 1 year amount of solar calendar data were converted into lunar calendar, and then applied the traditional water time system of West Sea by using AIS(Automatic Identification System) observation data gathered in Mokpo port for a year of 2013. As a result, it was found herein that the number of outbound ships was larger on the $2^{nd}-3^{nd}$ water times than the $7^{th}$ water times by 23-24 %. And the number of inbound ships was higher on the $12^{th}-13^{th}$ water times than the $9^{th}$ water time by 29-33 %. The hourly variation index of inbound and outbound ships according to time, in particular, was found to change in the form of sine function model. This study is expected to serve as a necessary basic material for development of maritime traffic management according to water time.

• Environmental and Resource Economics Review
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• v.15 no.2
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• pp.269-296
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• 2006

With the concern of the potential problems which can be observed in terms of the power supply of renewable energies, we need to analyze the impact of additional power generation capacities of renewable energy sources on peak load. Each renewable energy sources are dependent upon wind speed, solar radiation, head differences caused by lunar calendar. Considering that these exogenous renewable energy sources follow their own stochastic distributions, we analyze the probability distribution of the impact of each renewable energy power supply on peak load. As a conclusion, we note that traditional tools used for the analysis of power supply such as capacity factors are no longer appropriate for the analysis of renewable energy sources in that perspective.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.102.1-102.1
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• 2012

In this paper, we analyzed Korean historical records of the periodic comet Halley in three periods (Three Kingdoms, the Goryeo dynasty, and the Joseon dynasty) using various sources such as Samguksagi (History of the Three Kingdoms), Goryeosa (History of the Goryeo Dynasty), and Joseonwangjosillok (Annals of the Joseon Dynasty). To determine the apparition time of the comet at each return, we referred to the works of Kronk. For the Three Kingdoms period, we could not find any record relevant to Halley's comet from Samguksagi. Instead, we examined the suggestion that the phenomenon two Suns appearing on April 1, 760 (in a luni-solar calendar), which is recorded in Samgukyusa (Renaissance of the Three Kingdoms), indicates an appearance of comet Halley during the daytime. In contrast, we found that all the returns of Halley's comet during the Goryeo dynasty are recorded, although some accounts are questioned. In addition, we found that the appearance of Halley's comet in 1145 is also mentioned in a spirit-path stele made in 1178. For the Joseon dynasty period, we found that all the returns of the comet are recorded, as with the Goryeo dynasty, except for the return of 1910, in which the former dynasty fell. In conclusion, we think that this study will be helpful for understanding Korean historical accounts of Halley's comet.

• Journal of Astronomy and Space Sciences
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• v.41 no.2
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• pp.107-119
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• 2024

It is known that Chang-Hwa Park (1889-1962) transcribed a chronicle of the Goguryeo kingdom (BC 37-AD 668) of Korea (hereafter Goguri annal) from literature of the time that is no longer available. However, the authenticity of his transcription remains disputed. This study attempts to verify whether the Goguri annal is a pseudograph by analyzing the astronomical records in the annal. Although the Goguryeo kingdom fell in the year 668, the Goguri annal contains records up to the year 536. In this study, we have classified the astronomical records into eight categories and clustered them into two groups: a calendrical data group of reign-name and calendar date categories, and a celestial phenomena group of solar eclipse, trespass, comet, daylight appearance of Venus, meteor/meteorite, and other categories. The records of each category have been compared with those of the Samguksagi (History of the Three Kingdoms), Chinese chronicles, and with the results of modern computations wherever possible. From this comparison, we have not found any critical record that would indicate that the Goguri annal is a pseudograph, although the same astronomical records, with the exception of a few, are also found in the Samguksagi and Chinese chronicles.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.3
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• pp.277-293
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• 2008

We conducted a consensual, expansive, and successive study to compare cultural differences and similarities between Korean, Chinese and Japanese's Seasonal Festivals and Foods documentarily. It showed interesting results that the three countries had celebrated with similar meanings, and shared similar events and special foods. Seasonal Festivals happen throughout the year sequentially: the New Year Day, January $15^{th}$(first full moon festival), March $3^{rd}$(double three day), May $5^{th}$(double five day), July $7^{th}$(double seven day) and finally the Year Farewell Festival. While, the festival of a royal birthday of Buddha happens on April $8^{th}$ in both countries: Korea and Japan. There is also one of the big festivals called the harvest moon festival on August $15^{th}$, and this event celebrates with special foods both in Korea and China. On December $23^{th}$, it is a special day for both Chinese and Japanese, but they celebrate the day with different meanings to it. Three countries have a special seasonal event celebrated each other. Koreans have a special event called Sambok to overcome summer with special food during a middle of June to the beginning of July. Chinese have a special event for overcoming winter with soup on December $8^{th}$. Japanese have a special event with rice cake to safety on January $11^{th}$. On these seasonal festivals, it is different to note that two different kinds of calendars are used. The lunar calendar is used by Koreans and Chinese whereas the solar calendar is used by Japanese. Because of the similarity in Buddhism, and agricultural industry, and especially sharing Chinese Characters in words, these three countries have in common in many ways to celebrate Seasonal Festival, and it is very unique custom in the world. Nowadays; however, these traditional events and special foods are changing in more simplified version and almost disappearing in all three countries. Therefore, we suggest that the Seasonal Festivals and Foods should be more emphasized in flourishing and exchanging between Korea, China and Japan.

• Journal of Astronomy and Space Sciences
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• v.31 no.3
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• pp.215-223
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• 2014

In this paper, we report the analysis of Korean historical records on the periodic Halley's comet according to the period (i.e., the Three Kingdoms, Goryeo Dynasty, and Joseon Dynasty) using various sources such as the Samguksagi (The History of the Three Kingdoms), Goryeosa (The History of the Goryeo Dynasty), and Joseonwangjosillok (The Annals of the Joseon Dynasty). With regards to the apparition time of the comet for each return, we referred to the works of Kronk. For the Three Kingdoms period, we could not find any record relevant to Halley's comet from the Samguksagi. Furthermore, we examined the suggestion that the phenomenon of "two Suns" which appeared on April 1, 760 (in a luni-solar calendar), as recorded in the Samgukyusa (The Legends and History of the Three Kingdoms), indicates an instance of the the daytime appearance of Halley's comet. In contrast with the Three Kingdoms period, we found that all returns of Halley's comet are recorded during the Goryeo Dynasty, although others have questioned some accounts. We also found that the appearance of Halley's comet in 1145 is mentioned in a spirit-path stele made in 1178. For the Joseon Dynasty period, we found that all apparitions of the comet are recorded, as with the Goryeo Dynasty, except for the return of 1910, at which time the former dynasty had fallen. In conclusion, we think that this study will be helpful for understanding Korean historical accounts on Halley's comet.

• 한국태양에너지학회:학술대회논문집
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• 2009.04a
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• pp.184-189
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• 2009

In order to improve the operation of energy systems, it is necessary for the urban communities to have reliable optimization routines, both computerized and manual, implemented in their organizations. However, before a production plan for the energy system units can be constructed, a prediction of the energy systems first needs to be determined. So, several methodologies have been proposed for energy demand prediction, but due to uncertainties in urban community, many of them will fail in practice. The main topic of this paper has been the development of a method for energy demand prediction at urban community. Energy demand prediction is important input parameters to plan for the energy planing. This paper presents a energy demand prediction method which estimates heat and electricity for various building categories. The method has been based on artificial neural networks(ANN). The advantage of ANN with respect to the other method is their ability of modeling a multivariable problem given by the complex relationships between the variables. Also, the ANN can extract the relationships among these variables by means of learning with training data. In this paper, the ANN have been applied in oder to correlate weather conditions, calendar data, schedules, etc. Space heating, cooling, hot water and HVAC electricity can be predicted using this method. This method can produce 10% of errors hourly load profile from individual building to urban community.

• Atmosphere
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• v.31 no.5
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• pp.539-551
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• 2021

In this paper, the weather records in 'Nanjung Ilgi' were investigated and the weather characteristics of the southern coast of Korea (SC_Korea) was discussed. The Nanjung Ilgi is a personal diary written by admiral Yi Sun-sin from January 1592 to November 1598 during the 7-year war caused by the Japanese invasion. He is a respected great leader in the history of world naval warfare, winning all 23 battles against the Japanese. Of the 1593 days of diaries currently preserved, only 42 days have no weather records. Weather was recorded in detail, including sky conditions, precipitation, wind characteristics and others. Weather records were extracted from the diary, converted to the solar calendar, and compared with the meteorological data of Yeosu. The average annual precipitation day is about 90 days, which is similar to the current 95~100 days. As in the current climate, precipitation frequently occurs for about 30 days in summer, but less than 15 days in other seasons, and the rainy season starts from June 14 to 21 and ends from July 6 to 17. It seems that the abnormal cold and heat phenomena, which deviate significantly from the seasonal average climate, occurred on 6 and 21 days, respectively, over 7 years. This means that the weather records of Nanjung Ilgi can be used as valuable data on the climate of SC_Korea in the late 16th century. The fact that he recorded the weather even in such extreme battle conditions shows that he clearly recognized the importance of weather in warfare.