• Title/Summary/Keyword: star map

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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.

ANALYSIS OF THE KOREAN CELESTIAL PLANISPHERE: CH'ON-SANG-YUL-CHA-BUN-YA-JI-DO

  • PARK CHANGBOM
    • Journal of The Korean Astronomical Society
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    • v.29 no.spc1
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    • pp.433-437
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    • 1996
  • We have analyzed the content of the Korean stone star chart. Ch'on-Sang-Yul-Cha-Bun-Ya-Ji-Do(here-after Ch'on-Sang-Do). In the star map we have found 1468 stars, 4 more than the Chinese star catalog Bo-Chun-Ga. The four extra stars form a constellation, Jong Dae Boo. The map projection law used in the star chart is found to be the polar equtorial and equidistance projection. The linear distance of an object on Ch'on-Sang-Do from the center is linearly proportional to the north polar angular distance. We have found from a statistical analysis that most stars with declination lower than 50 are at positions representing the epoch of around the first century. On the other hand, stars near the north pole with declination higher than 50 are at the epoch of about 1300, which is close to the time the chart was engraved. This implies that the original Ko-Gu-Rye Dynasty's star chart has been revised by astronomers of Cho-Sun Dynasty. We have also shown that stars on Ch'on-Sang-Do are engraved in such a way that their area is linearly proportional to the visual magnitude.

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A Study on the Standardization Model of Noise Map (소음오염도의 지도표현 표준화 모델)

  • 조기호
    • Journal of KSNVE
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    • v.10 no.3
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    • pp.410-422
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    • 2000
  • This paper proposes a model of standardized noise map in korea, The standardization of noise map is accomplished by standardizing the way of map description and by applying international noise mapping criteria to Korean environment. The proposed model can be an useful star or the production of national standardized noise map in Korea.

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Environmental effect on the chemical properties of star forming galaxies in the Virgo cluster

  • Chung, Jiwon;Rey, Soo-Chang;Kim, Suk;Lee, Ung
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.46.2-46.2
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    • 2013
  • We utilize Sloan Digital Sky Survey DR7 spectroscopic data of ~380 star forming galaxies in the Virgo cluster to investigate their chemical properties depending on the environments. The chemical evolution of galaxies is linked to their star formation histories as well as to the gas interchange in different environments. We derived star formation rate (SFR) and gaseous metallicity (e.g., oxygen abundance) of star forming galaxies. Combining with GALEX ultraviolet photometry and ALFALFA HI 21 cm data, we examine the relations between SFRs, metallicity, and HI deficiency of galaxies in various regions of the Virgo cluster. We also quantify the degree of ram pressure around galaxy using the ROSAT X-ray surface brightness map. We discuss environmental effects on the chemical properties and evolution of star forming galaxies.

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An Agro-ecological Land Suitability Analysis Using GIS For Oil Palm Plantation in Southern Thailand

  • Dansagoonpon, Sutat;Tripathi, Nitin K;Borne, Frederic;Clemente, Roberto S.
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.970-972
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    • 2003
  • Due to rapid increase in the demand of Natural Rubber (NR) few years ago, NR price sore very higher. The rubber plantation in Thailand expanded very fast to non traditional areas with the result Thai become the biggest NR exporting country in the world. However, the average yield is still lower compared to experimental yield of RRIT (Rubber Research Institute of Thailand) or just 60 % (RRIT, 1998). This is due to many of new rubber planting areas, which are not suitable. The Thai Ministry of Agriculture and Cooperatives thus has set 'The complete cycle development strategies for natural rubber' in the medium-term measures by reducing the rubber planting areas by 300,000 rai (1 rai = 0.16ha) through replanting with oil palm. The aim of this study is to find out land having lowest potential for rubber production (R3) but highest for oil palm production (P1). Find areas which are unsuitable for rubber and can be replaced by oil palm in order to get a better agricultural production. The study was applied upon Krabi province, Thailand. Crops requirement, degree of limitation to crops growth, climatic data, crops yield, soil map, topographic map etc., were used to evaluate land potential for both rubber and oil palm production according to FAO framework (Sys, 1992). An Agro-ecological suitability map for rubber and oil palm were produced. This was done by mean of GIS. The database was generated and guide map for the decision makers in view of suitable crop substitution was prepared.

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FDDI Throughput and Application Analysis of MAP Network Construction in Manufactruing Environment (제조 환경에서 MAP 네트워크 체제의 FDDI 효율과 적용 해석)

  • Kim, Jeong-Ho;Lee, Min-Nam;Lee, Sang-Beom
    • The Transactions of the Korea Information Processing Society
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    • v.2 no.1
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    • pp.95-105
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    • 1995
  • An appendix to the MAP 3.0 specification notes that there are primary advantages to use of fiber optics : noise immunity, ability to run in difficult electrical environments, safety and high data rates. All of these may be quite useful in various manufacturing environments. In this paper, we study on construction schmes for a fiber-based 802.4 MAP system including the use of both bus and star topologies. We suggest passive star network and FDDI network for manufacturing environment. And then, we propose the FDDI protocol including the use a dual ring topology running at 100 Mbps to physical and datalink layer of MAT specification and analysis it's protocol and topology for abilities in manufacturing environments, We evaluate about applications service, time-critical processing and topology of two models in manufacturing environment.

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A QUALITY CHECK OF THE AKARI MID-INFRARED ALL-SKY DIFFUSE MAP TOWARD THE MASSIVE STAR-FORMING REGIONS NGC 6334 AND NGC 6357

  • Sano, Hidetoshi;Amatsutsu, Tomoya;Kondo, Toru;Nakamichi, Keichiro;Yamagishi, Mitsuyoshi;Ishihara, Daisuke;Oyabu, Shinki;Kaneda, Hidehiro;Tachihara, Kengo;Fukui, Yasuo
    • Publications of The Korean Astronomical Society
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    • v.32 no.1
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    • pp.21-23
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    • 2017
  • We present a comparative study of CO and polycyclic aromatic hydrocarbon (PAH) emission toward a region including the massive star-forming regions of NGC 6334 and NGC 6357. We use the NANTEN $^{12}CO(J=1-0)$ data and the AKARI $9{\mu}m$ All-Sky diffuse map in order to evaluate the calibration accuracy of the AKARI data. We confirm that the overall CO distribution shows a good spatial correspondence with the PAH emission, and their intensities exhibit a good power-law correlation with a spatial resolution down to 4' over the region of $10^{\circ}{\times}10^{\circ}$. We also reveal poorer correlation for small scale structures between the two quantities toward NGC 6357, due to strong UV radiation from local sources. Larger scatter in the correlation toward NGC 6357 indicates higher ionization degree and/or PAH excitation than that of NGC 6334.

Near-infrared Polarimetric Study of N159/N160 Star Forming Regions in the Large Magellanic Cloud

  • Kim, Jaeyeong;Jeong, Woong-Seob;Pak, Soojong;Pyo, Jeonghyun;Tamura, Motohide
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.67.1-67.1
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    • 2016
  • We observed two star forming regions, N159 and N160, in the Large Magellanic Cloud with SIRPOL, the polarimeter of the Infrared Survey Facility (IRSF) in South Africa. The photometric and polarimetric observations are done in three near-infrared bands, J, H, and Ks. We measured Stokes parameters of point sources and calculated their degrees of polarization and polarization angles. The polarization vector map shows complex features associated with dust and gas structures. Overall features of the magnetic field in N159 and N160 regions are different from each other and appear to be related to local environments, such as interior and boundary of shell structure, existence of star-forming HII regions, and boundaries between HII regions and dense dark clouds. We discuss the relation between the structure of magnetic field and the local properties of dust and gas in N159 and N160 regions by comparing our polarization vector map with images of $H{\alpha}$, mid-infrared, and $^{12}CO$ emissions, respectively by WFI of MPG/ESO telescope, Spitzer IRAC, and NANTEN.

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Rotation Invariant 3D Star Skeleton Feature Extraction (회전무관 3D Star Skeleton 특징 추출)

  • Chun, Sung-Kuk;Hong, Kwang-Jin;Jung, Kee-Chul
    • Journal of KIISE:Software and Applications
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    • v.36 no.10
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    • pp.836-850
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    • 2009
  • Human posture recognition has attracted tremendous attention in ubiquitous environment, performing arts and robot control so that, recently, many researchers in pattern recognition and computer vision are working to make efficient posture recognition system. However the most of existing studies is very sensitive to human variations such as the rotation or the translation of body. This is why the feature, which is extracted from the feature extraction part as the first step of general posture recognition system, is influenced by these variations. To alleviate these human variations and improve the posture recognition result, this paper presents 3D Star Skeleton and Principle Component Analysis (PCA) based feature extraction methods in the multi-view environment. The proposed system use the 8 projection maps, a kind of depth map, as an input data. And the projection maps are extracted from the visual hull generation process. Though these data, the system constructs 3D Star Skeleton and extracts the rotation invariant feature using PCA. In experimental result, we extract the feature from the 3D Star Skeleton and recognize the human posture using the feature. Finally we prove that the proposed method is robust to human variations.

A Navigation System for a Patrol Robot in Indoor Environments (실내 환경에서의 경비로봇용 주행시스템)

  • Choi, Byoung-Wook;Lee, Young-Min;Park, Jeong-Ho;Shin, Dong-Kwan
    • The Journal of Korea Robotics Society
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    • v.1 no.2
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    • pp.117-124
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    • 2006
  • In this paper, we develope the navigation system for patrol robots in indoor environment. The proposed system consists of PDA map modelling, a localization algorithm based on a global position sensor and an automatic charging station. For the practical use in security system, the PDA is used to build object map on the given indoor map. And the builded map is downloaded to the mobile robot and used in path planning. The global path planning is performed with a localization sensor and the downloaded map. As a main controller, we use PXA270 based hardware platform in which embedded linux 2.6 is developed. Data handling for various sensors and the localization algorithm are performed in the linux platform. Also, we implemented a local path planning algorithm for object avoidance with ultra sonar sensors. Finally, for the automatic charging, we use an infrared ray system and develop a docking algorithm. The navigation system is experimented with the two-wheeled mobile robot using North-Star localization system.

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