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THE PROTECT10N OF PASSIVE SERVICES FROM UNWANTED EMISSIONS, IN PARTICULAR FROM SPACE SERVICE TRANSMISSION (불요발사 (우주업무의 발사)로부터 수동업무의 보호)

  • Chung, Hyun-Soo;;Je, Do-Heung;Park, Jong-Min;Kim, Hyo-Ryoung;Ahn, Do-Seob;Oh, Dae-Sub
    • Publications of The Korean Astronomical Society
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    • v.18 no.1
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    • pp.97-110
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    • 2003
  • WRC-03 was held between 9 June and 4 July 2003 in Geneva, Switzerland. Over 2,200 delegates from 138 ITU Member States attended the Conference. The delegates considered some 2,500 proposals, and over 900 numbered documents related to 50 agenda items. The final output of the Conference consists of 527 pages of new and revised text of the Radio Regulations. This paper provides some details about the outcome of the radio astronomy related issues at the WRC-03 Conference. It is divided into two part: a) Agenda item1.8.2 and b) Agenda item 1.32, related to radio astronomy. Relevant extracts from the Final Acts of WRC-03 are given in the Appendix. Agenda item 1.8.2 was one of the most controversial Agenda Items at WRC-03. Studies were carried out within ITU-R TG 1/7 for the last three years; the results of these studies are summarized in Recommendation ITU-R SM.1633. The Conference adopted a new footnote (5.347A), that calls for the application of Resolution 739 (WRC-03) in the 1452-1492 MHz, 1525-1559 MHz, 1613.8-1626.5 MHz, 2655-2670 MHz, 2670-2690 MHz and 21.4-22.0 GHz bands. Agenda item 1.32 is to consider technical and reglatory provisions concerning the band 37.5-43.5 GHz, in accordance with Resolutions 128 (Rev.WRC-2000) and 84 (WRC-2000). WRC-03 reviewed and adjusted the New footnotes 5.551H and 5.551I cover the protection of radio astronomy observations in the 42.5-43.5 GHz band from unwanted emissions by non-geostationary (5.551H) and geostationary (5.551I) FSS and BSS systems, respectively.

A STUDY ON THE PROJECTION METHOD OF THE 「HON-CHON-JEON-DO」 (「혼천전도」의 투영법 고찰)

  • KIM, K.T.;CHO, YONGHAN
    • Publications of The Korean Astronomical Society
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    • v.34 no.1
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    • pp.1-16
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    • 2019
  • "Hon-Chon-Jeon-Do" is a woodcut star map with the size of $79.4cm{\times}127.5cm$, and was widely disseminated as it was made into a set with Kim, Jung Ho's "Yeoji-Jeon-Do". This study confirmed that Yixiang kaocheng xubian ("의상고성속편") star catalogue was used as a source to produce the star map, and the stereographic projection was applied with the projection center being the mid-point (Q) between the celestial and ecliptic north poles. The 'mid-circle' around the Q is arisen between the equator and the ecliptic, and on this circle, the hour angle and the ecliptic longitude of a star can be marked using the same scale. This means that the hour of the day and the season of the year can be read on the same dial of the mid-circle, and the application of this character in the practical use was the key point of the star map production. By observing either transits or positions of the 28 xiu (宿), it is easy to find the corresponding season and time by simply reading the dial on the mid-circle. This is just the function of a portable almanac and thus by disseminating it widely, the convenience of the people would have been promoted. For this reason, it can be stated that "Hon-Chon-Jeon-Do" was a practical astronomical tool which was produced by the western astronomical projection method and was used to find time and season. Choi, Han Ki and Kim, Jung Ho are strong candidates for the makers of this star map. The time of production is estimated to be 1848 ~ 1857, and "Hon-Chon-Jeon-Do" could be regarded as a good contributor to popularization of astronomy in the late Joseon Dynasty.

MECHANICAL POWER SYSTEM OF TONGCHEON-UI, AN ASTRONOMICAL CLOCK MADE BY HONG, DAE-YONG (홍대용이 제작한 천문시계 통천의의 기계동력시스템)

  • MIHN, BYEONG-HEE;YUN, YONG-HYUN;KIM, SANG HYUK;KI, HO CHUL
    • Publications of The Korean Astronomical Society
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    • v.35 no.3
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    • pp.43-57
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    • 2020
  • Hong, Dae-Yong manufactured the Tongcheon-ui (Pan-celestial Armillary Sphere) with cooperating clock researcher Na, Kyeong-Jeok, and its craftsman An, Cheo-In, in Naju of Jeolla Province in 1760 ~ 1762. Tongcheon-ui is a kind of astronomical clock with an armillary sphere which is rotated by the force generated by a lantern clock's weight. In our study, we examine the lantern clock model of Tongcheon-ui through its description of the articles written by Hong himself. As his description, however, did not explain the detail of the mechanical process of the lantern clock, we investigate the remains of lantern clocks in the possession of Korea University Museum and Seoul National University Museum. Comparing with the clocks of these museums, we designed the lantern clock model of Tongcheon-ui which measures 115 mm (L) × 115 mm (W) × 307 mm (H). This model has used the structure of the striking train imitated from the Korea University Museum artifact and is also regulated by a foliot escapement which is connected to a going train for timekeeping. The orientation of the rotation of the going train and the striking train of our model makes a difference with the remains of both university museums. That is, on the rotation axis of the first gear set of Tongcheon-ui's lantern clock, the going and the striking trains take on a counterclockwise and clockwise direction, respectively. The weight of 6.4 kg makes a force driving these two trains to stick to the pulley on the twine pulling across two spike gears corresponding to the going train and the striking train. This weight below the pulley may travel down about 560 mm per day. We conclude that the mechanical system of Tongcheon-ui's lantern clock is slightly different from the Japanese style.

ANALYSIS OF SOLAR RESEARCH ACTIVITIES PUBLISHED IN NORTH KOREAN JOURNALS (북한 학술지에 실린 태양 연구 활동 분석)

  • KIM, SUJIN;YANG, HONG-JIN;CHUNG, JONG-KYUN;YIM, INSUNG
    • Publications of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.37-45
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    • 2021
  • We have analyzed 42 research papers regarding on the solar astronomy written by North Korea scientists to investigate the current status of astronomical activities in North Korea. The papers are surveyed from the 'Bulletin of Astronomy', the 'Physics', the 'Bulletin of Academy of Science', and the 'Natural Science' in North Korea, and SCI journals. In addition, we refer to the presentation material announced in the 2015 IAU by director of Pyongyang Astronomical Observatory (PAO) and the 2013 OAD/IAU reports. We have analyzed the papers statistically according to three criteria such as research subject, research field, and research members. The main research subjects are the sunspot (28%), observation system (21%), and space environments (19%). The research fields are distributed with data analysis (50%), numerical method (29%), and instrument development (21%). There have been 25 and 9 researchers in the solar astronomy and space environment, respectively since 1995. North Korea's solar research activities were also investigated in three area: instrument, solar physics, and international research linkage. PAO has operated two of sunspot telescope and solar horizontal telescope for spectroscopy and polarimetry, but there is no specific information on solar radio telescopes. North Korea has cooperated in solar research with Europe and China. We expect that the results of this study will be used as useful resource in supporting astronomical cooperation between South and North Korea in the future.

ANALYSIS OF ANGBU-ILGU, A STONE MATERIAL IN THE LATE JOSEON DYNASTY (조선 후기 석제 앙부일구 분석)

  • SANG HYUK, KIM;BYEONG-HEE, MIHN;JAE-YOUNG, KIM
    • Publications of The Korean Astronomical Society
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    • v.37 no.3
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    • pp.35-47
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    • 2022
  • This study investigated the stone Angbu-ilgu (scaphe sundial) of the Korea Meteorological Administration (KMA) and the Seoul Museum of History (SMH). Since the first Angbu-ilgu was produced in Korea in 1434 (the year of the reign of King Sejong), Angbu-ilgu has been reproduced with various materials. The upper surface of these two stone Angbu-ilgus symbolizes the horizon. On the hemisphere concave at the center of the horizon, the South Pole, the time line, and the season line are engraved. On the horizon of both the KMA and SMH Angbu-ilgus, the schematic, typeface, and composition of the inscription completely coincide with each other. In this study, it was estimated that the appearance of the KMA Angbu-ilgu, which was damaged at some point previously at least once, was similar to that of the SMH Angbu-ilgu, and this means that it is superficially similar with Treasure No 840, the stone horizontal sundial. In the concave hemisphere of both the stone Angbu-ilgus of the KMA and SMH, there are hour lines and 24 solar-term lines (13 line), and there is an intersection point where these lines meet the horizon, respectively. It can be verified that these intersections of these two Angbu-ilgus can be calculated as having a latitude of +37°39'15". The hour lines of the two stone Angbu-ilgus show that they were made after about 1900.

STUDY ON THE RESTORATION MODEL OF JEONGNAM-ILGU, CREATED DURING THE REIGN OF KING SEJONG OF THE JOSEON DYNASTY (조선 세종대에 창제된 정남일구 복원모델 연구)

  • JIWON PARK;BYEONG-HEE MIHN;SANG HYUK KIM;YONG-GI KIM
    • Publications of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.1-12
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    • 2023
  • Numerous Sundials were fabricated during the reign of King Sejong of the Joseon Dynasty. One among them is Jeongnam-Ilgu (the Fixing-South Sundial), where the time can be measured after setting up the suitable meridian line without a compass. We reconstructed the new Jeongnam-Ilgu model based on the records of 'Description of Making the Royal Observatory Ganui (簡儀臺記)' in the Veritable Record of King Sejong. Jeongnam-Ilgu has a summer solstice half-ring under a horizontal ring which is fixed to two pillars in the north and south, and in which a declination ring rotates around the polar axis. In our model, the polar axis matches the altitude of Hanyang (that is Seoul). There are two merits if the model is designed to install the polar axis in the way that enters both the north and south poles and rotates in them: One is that it is possible to fix the polar axis to the declination ring together with the cross-strut. The other is that a twig for hanging weights can be protruded on the North Pole. The declination ring is supposed to be 178 mm in diameter and is carved on the scale of the celestial-circumference degrees on the ring's surface, where a degree scale can be divided into four equal parts through the diagonal lines. In addition, the time's graduation that is drawn on the summer solstice half-ring makes it possible to measure the daytime throughout the year. An observational property of Jeongnam-Ilgu is that a solar image can be obtained using a pin-hole. The position cast by the solar image between hour circles makes a time measurement. We hope our study will contribute to the restoration of Jeongnam-Ilgu.

ANALYSIS OF ASTRONOMY CONTENT IN NATIONAL SCIENCE CURRICULUM OF KOREA (한국 과학과 교육과정 내 천문학 내용 분석)

  • HYUNJIN SHIM;WOOJIN KWON;DOHYEONG KIM;CHAN-GYUNG PARK;JUNGJOO SOHN;IN-OK SONG;SUNG-HO AN;SUYEON OH;JEONG AE LEE;BEOMDU LIM
    • Publications of The Korean Astronomical Society
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    • v.38 no.3
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    • pp.125-145
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    • 2023
  • This study investigates the integration of astronomy-related topics in the Korean national science curricula spanning from 1945 to 2023. We analyze the placement and extent of astronomy content across different school levels. Astronomy contents in the science curricula have changed in response to social needs (e.g., practical knowledge required for agriculture and fishery) and advancement in astronomical research (e.g., the discovery of exoplanets and the suggestion of new cosmological parameters). Contents addressing the motions of celestial objects and stellar physical properties have remained relatively consistent. In the latest 2022 revised national curriculum, scheduled for implementation in 2024, several elements, such as coordinate systems, have been removed, while the inquiry activities using digital tools are emphasized. The incorporation of the cosmic perspectives in the national curriculum, as well as astronomy education within the context of education for sustainable development, remains limited even in the most recent curriculum. For future life revisions, the active participation of researchers is needed to reflect the latest astronomical research progress and scientific characteristics in the field of astronomy.

STATISTICAL ANALYSIS FOR ASTRONOMICAL RECORDS OF THE HYEONJONG-DONGGUNG-ILGI (1649-1659) (현종동궁일기(1649-1659)의 천문기록 통계분석)

  • UHN MEE, BAHK;BYEONG-HEE, MIHN;KI-WON, LEE;SANG HYUK, KIM;JAE YEON, HYUN;YONG GI, KIM
    • Publications of The Korean Astronomical Society
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    • v.37 no.3
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    • pp.59-79
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    • 2022
  • We investigated the records of astronomical phenomena in the Hyeonjong-Donggung-Ilgi written by the educational office for a crown prince, Sigang-won, during the time of a crown prince of the king Hyeonjong (i.e., from 1649 to 1659). Of the total of 3,625 days, 3,044 astronomical accounts were compiled from astronomical records of 2,003 days. We classified these astronomical accounts into 16 items, grouped into five categories, and statistically analyzed each group. In our analysis, the accounts for atmos-pheric optical phenomena equates to 57.9% of the total, and for celestial phenomena visible during the daytime the percentage is 17.3%. The records related to the approach between two objects such as planets, moon, and stars account for 3.3%, and solar or lunar eclipses take up 0.6%. The ratio of accounts regarding meteor, comet, and fire light (火光) stand at 13.8%, 0.30%, and 6.8%, respectively. Sunny days account for 71.1% of all days per year during this period. We determined that the distribution of the fire light by month is similar to that of the solar halo. We also found that the astronomical records from the Annals of the Joseon Dynasty correspond to only 30% of those of the Hyeonjong-Donggung-Ilgi for the same period. In particular, the phenomena of celestial objects occurring outside the atmosphere are transmitted to the Annals of the Joseon Dynasty in a higher proportion than the phenomena inside the air. It is therefore necessary to use a historical diary like a Donggung-Ilgi to interpret the phenomena in the air such as atmospheric optical events, meteor, and fire light.

COMPARISON OF THE TIME-SIGNAL SYSTEM OF AUTOMATIC WATER CLOCKS DURING THE YUAN DYNASTY AND THE KING SEJONG ERA OF THE JOSEON DYNASTY (원대(元代)와 세종대(世宗代) 자동 물시계 시보시스템 비교)

  • YONG-HYUN YUN;SANG HYUK KIM;BYEONG-HEE MIHN;BYONG GUEN LEEM
    • Publications of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.1-12
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    • 2024
  • In this study, we investigated the time signal devices of Deungnu (circa 1270) and Gungnu (1354), the water clocks produced during the Yuan Dynasty (1271-1368). These clocks influenced Heumgyeonggaknu (1438) of the Joseon Dynasty (1392-1910), exemplifying the automatic water clocks of the Yuan Dynasty. Deungnu, Gungnu, and Heumgyeonggaknu can be considered as automatic mechanical clocks capable of performances. The Jega-Yeoksang-Jip (Collection of Calendrical and Astronomical Theories of Various Chinese Masters) contains records of Deungnu extracted from the History of the Yuan Dynasty. We interpreted these records and analyzed reproduction models and technical data previously produced in China. The time signal device of Deungnu featured a four-story structure, with the top floor displaying the four divine constellations, the third floor showcasing models of these divinities, the second floor holding 12-h jacks and a 100-Mark ring, and the first floor with four musicians and a 100-Mark Time-Signal Puppet providing a variety of visual attractions. We developed a 3D model of Deungnu, proposing two possible mechanical devices to ensure that the Time-Signal Puppet simultaneously pointed to the 100-Mark graduations in the east, west, south, and north windows: one model reduced the rotation ratio of the 100-Mark ring to 1/4, whereas the other model maintained the rotation ratio using four separate 100-Mark rings. The power system of Deungnu was influenced by Suunuisangdae (the water-driven astronomical clock tower) of the Northern Song Dynasty (960-1127); this method was also applied to Heumgyeonggaknu in the Joseon Dynasty. In conclusion, these automatic water clocks of East Asia from the 13th to 15th centuries symbolized creativity and excellence, representing scientific devices that were the epitome of clock-making technology in their times.

ANALYSIS OF THE USAGE OF NAM BYEONG-CHEOL'S ARMILLARY SPHERE IN UIGIJIPSEOL IN THE 19TH CENTURY (19세기 남병철 『의기집설(儀器輯說)』 혼천의 용법 분석)

  • HONG SOON CHOI;SANG HYUK KIM;BYEONG-HEE MIHN;KYOUNG-UK NAM;GEOYOUNG-HAN YOO;YONGGI KIM
    • Publications of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.13-26
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    • 2024
  • The armillary sphere, an astronomical observation device embodying the Orbital Heaven Theory of the Later Han Dynasty in China, holds both historical and scientific significance. It has been produced in various forms by many individuals since its inception in the era of King Sejong in the Joseon Dynasty. A prominent figure in this field was Nam Byeong-cheol (南秉哲, 1817-1863), known for his work 'Uigijipseol' (儀器輯說), published in 1859, which detailed the history, production methods, and usage of the armillary sphere. This text particularly highlights 21 applications of the armillary sphere, divided into 33 measurements, covering aspects like installation, time, and positional measurements, supplemented with explanations of spherical trigonometry. Despite numerous records of the armillary sphere's design during the Joseon Dynasty, detailed usage information remains scarce. In this study, the 33 measurements described in 'Uigijipseol' (儀器輯說) were systematically classified into six for installation, nineteen for position measurement, seven for time measurement, and one for other purposes. Additionally, the measurement methods were analyzed and organized by dividing them into the ecliptic ring, moving equatorial ring, and fixed equatorial ring of the armillary sphere. In other words, from a modern astronomical perspective, the results of schematization for each step were presented by analyzing it from the viewpoint of longitude, right ascension, and solar time. Through the analysis of Nam's armillary sphere, this study not only aims to validate the restoration model of the armillary sphere but also suggests the potential for its use in basic astronomical education based on the understanding of the 19th-century Joseon armillary sphere.