• Title/Summary/Keyword: South Pole

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Astronomy in Antarctica

  • Burton, Michael
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.26-26
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    • 2013
  • The high Antarctic plateau is the driest and coldest environment on the surface of the Earth and offers superlative conditions for the conduct of a wide range of astronomical observations, from optical to millimetre wavebands. This includes, especially, the infrared - where the sky background is greatly reduced from temperate sites - and the sub-millimetre / THz bands - where new or cleaner atmospheric windows can be viewed through. Astronomical observations have now been conducted from five locations on the Antarctic plateau - the South Pole, Domes A, C and F, and Ridge A. Ambitious plans for the construction of observatories there have been announced. An IAU Symposium on "Astrophysics from Antarctica" featured as part of last year's IAU General Assembly in Beijing. This talk will provide an overview of astronomy in Antarctica, describing the special conditions that make some forms of observation particularly favourable there, and discuss the development of observatories on the Antarctic plateau and the plans for their future development.

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A Study of Wind-power Generations at the south-east coast of Ul-san (울산 남동부 해안지역에서의 소용량 풍력발전 가능성에 관한 연구)

  • Park, M.D.;Pack, M.S.;Lee, G.W.;Lee, Y.S.
    • Proceedings of the KIEE Conference
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    • 2003.07b
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    • pp.1392-1394
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    • 2003
  • This paper presents the actual test data of 3 phase, 9 pole, 3.6 [kw] synchronized wind-power generator controlled by hinged vane system and the possibilities of the small mount wind-power generations at the south-east coast of Ul-san. It also shows the data of the wind-velocity acquired by wind-direction sensor, calculation and analysis of the estimated electrical generation power, energy storage systems, and the efficient usages of the wind-power system.

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Palaeomagnetism of the Taedong Supergroup in the Kimpo Area (김포(金浦))지역 대동누층군(大同累層群)에 대한 고자적(古磁的) 연구)

  • Kim, In-Soo;Min, Kyung Duck;Lee, Mi Yeong;Kang, Hee-Cheol;Chun, Hee Young
    • Economic and Environmental Geology
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    • v.26 no.2
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    • pp.193-206
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    • 1993
  • A total of 111 independently oriented core samples were drilled at 12 sites in fue Kimpo area ($37.70^{\circ}N$, $126.55^{\circ}E$) of the Taedong Supergroup. The Taedong strata are composed of sandstone, conglomeratic sandstone, shale and thin coal seams. The age of the strata is known to be Late Triassic-Early Jurassic according to freshwater Esfuerites and plant fossil (Dictyophyllum-Clathropteris flora) contents. Through AF and thermal demagnetization, an area-mean ChRM direction of $D=48.3^{\circ}\;I=40.3^{\circ}\;{\alpha}_{95}=7.9^{\circ}\;k=59.5$, n=7 was obtained. It passed fold and reversal test in the formation-mean level. Fold test was not significant in the area-mean level. The palaeomagnetic north pole calculated from the area-mean lies at $46.3^{\circ}N$, $222.0^{\circ}E$ with dp=5.7, $dm=9.5^{\circ}$. This pole position is very similar to those of the South China Block (SCB) in Triassic times. Palaeolatitude of the Kimpo area in the Taedong times was $23.0^{\circ}N$, again very similar to the palaeolatitude of the South China Block in the Late Triassic. This low latitude of the study area at the time of deposition explains the tropical-subtropical nature of fossil contents of the Taedong Supergroup.

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Multi-wavelength Extragalactic Studies in the AKARI Deep Field - South

  • Jeong, Woong-Seob;Kim, Minjin;Ko, Jongwan;Park, Sung-Joon;Ko, Kyeongyeon;Jo, Youngsoo;Lee, Min Gyu;Seo, Hyun Jong;Kim, Taehyun;Pyo, Jeonghyun;Lee, Dongseob;Kim, Il-Joong
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.2
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    • pp.31.4-32
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    • 2018
  • The ADF-S (AKARI Deep Field - South) toward South Ecliptic Pole is one of the deep survey fields designed for the study of Cosmic Infrared Background (CIB). Owing to the easy accessibility with space missions and its low background brightness, the deep extragalactic survey was initiated by AKARI deep far-infrared observations and it will be performed by other future missions (e.g., Euclid, NISS, SPHEREx). The recent optical survey with KMTNet enabled us to identify the optical counterparts for dusty star-forming galaxies such as ULIRG, DOG, SMG. In addition, the NISS will perform the valuable spectro-photometric survey in the ADF-S. Those multi-wavelength data sets helps to trace the major galaxy population contributing to the CIB. Here, we introduce the extragalactic survey with the NISS and report the current status of the multi-wavelength extragalactic studies in the ADF-S.

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Effect of a Static Magnetic Field on Susceptibility to Ethanol-Induced Hepatic Dysfunction in Rats

  • Park, Kap-Joo;Kim, Eun-Jung;Cho, Myung-Hwan;Lee, Jae-Seok
    • Food Science and Biotechnology
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    • v.15 no.6
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    • pp.833-837
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    • 2006
  • To determine whether alcohol-treated rat liver cells can be protected by a static magnetic field (SMF), we analyzed the blood chemistry and histology of hepatic tissue removed from alcohol-exposed rats that had been exposed to a static magnetic field. The rats were exposed to a 0.3 tesla (3,000 gauss) magnetic field (MF) for 24 hr daily for 5 weeks with appropriate controls. Glutamic pyruvic transaminase activity and the triglyceride levels in animals exposed to the north (N) or south (S) pole of the MF decreased significantly (p<0.01 and p<0.05, respectively) compared with negative control animals with alcohol exposure. A histological examination of hepatic tissue revealed a moderate to severe accumulation of fat vacuoles of various sizes in the cytoplasm of the hepatocytes of animals in the negative control group throughout the study; whereas in groups exposed to the MF poles, fewer fat vacuoles were seen compared with the negative control group. Electron microscopic observations showed that exposure to the N or S pole protected organelles, including the nucleus, from damage during exposure to this toxic agent, as indicated by the fact that the nucleus and the mithochondria virtually retained their shape throughout this study. These results suggest that exposure to a SMF could be an excellent way of protecting against alcohol-induced damage to the rat liver cell.

Status of the MIRIS Data Reduction and Analysis

  • Pyo, Jeonghyun;Kim, Il-Joong;Jeong, Woong-Seob;Lee, Dae-Hee;Moon, Bongkon;Park, Youngsik;Park, Sung-Joon;Park, Won-Kee;Lee, Duk-Hang;Nam, Uk-Won;Han, Wonyong;Seon, Kwang-Il;Matsumoto, Toshio;Kim, Min Gyu;Lee, Hyung Mok
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.2
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    • pp.37.2-37.2
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    • 2016
  • MIRIS (Multi-purpose InfraRed Imaging System) is a compact near-infrared space telescope launched in 2013 November as the main payload of STSAT-3 (Science and Technology Satellite 3). The main missions of MIRIS are 1) the $Pa{\alpha}$ line survey along the Galactic plane, 2) the large area (${\sim}10^{\circ}{\times}10^{\circ}$) surveys of three pole regions (north ecliptic pole, and north and south Galactic poles), and 3) the monitoring observations toward the north ecliptic pole. MIRIS started observations for the main missions in 2014 March and finished in 2015 May. While MIRIS was taking the observation data and afterward, we are continuing the analysis of data. Based on the results from analysis, the data reduction pipeline has been revised. In this talk, we introduce the revised version of the MIRIS data reduction pipeline and the status of the data reduction and anlaysis.

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Effects of Magnetic Pole on Orientation of Bull Sperm Treated by Dithiothreitol or Heparin

  • Pham, Du Ngoc;Shinjo, Akihisa;Kurnianto, Edy
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.2
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    • pp.155-162
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    • 2001
  • Effect of the north (N) or south pole (S) of a magnet and dithiothreitol (DTT) or heparin sodium (H) on the orientation of bull sperm were studied. Sperm were collected from four Japanese Black bulls of Okinawa Prefectural Livestock Experimental Station were treated with various concentrations of DTT or H during the first and sixth days and were then exposed them to N or S with a magnetic field of 3,000 Gauss for 24 hours. Experimental results showed that both N and S significantly increased the perpendicular oriented percentage of bull sperm in most treatments not treated or treated with DTT or H. Anisotropy of magnetic field of bull sperm was the main cause which induced them to orient perpendicular to the magnetic direction. The results of the experiment also showed that, in most cases, the two polarities had the same effect on the orientation of bull sperm. However, in some cases, N exerted a stronger effect on the perpendicular percentage of bull sperm than S, such as with the 20 mM DTT treatment at the first and sixth days and the 100 units H treatment at the sixth day. These cases showed that the perpendicular oriented percentage of bull sperm at N was significantly higher than that of S. It was only the 100 units heparin treatment at S both at the first and sixth days that upward perpendicular orientation was higher than that at N. This might be due to the fact that protamin-DNA structure of a small number of bull sperm nuclei slightly changed because of heparin action.

Properties of High-Redshift Dust-Obscured Galaxies Revealed in the ADF-S

  • Kim, Seongjae;Jeong, Woong-Seob;Park, Daeseong;Kim, Minjin;Hwang, Hoseong;Park, Sung-Joon;Ko, Kyeongyeon;Seo, Hyun Jong
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.62.2-62.2
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    • 2019
  • The ADF-S (AKARI Deep Field - South) toward South Ecliptic Pole is one of the deep survey fields designed for the study of Extragalactic Background Light (EBL). The deep extragalactic survey was initiated by AKARI far-infrared deep observations. Other space missions (e.g., Euclid, NISS, SPHEREx) will perform the deep observations in the ADF-S. Based upon the recent optical survey with KMTNet, we can identify the optical counterparts for dusty star-forming galaxies such as ULIRG, DOG, SMG. Among them, the Dust-Obscured Galaxies (hereafter DOGs with f(24um)/f(R) > 1,000) in the heavily obscured system are expected to play an important role in the formation of most massive galaxies. We have newly discovered ~100 DOGs in ~12 sq. deg. of the ADF-S from our optical survey with KMTNet. We also confirmed that some of DOGs host the most luminous AGN for their black hole masses through the near-infrared spectroscopic follow-ups. Here, we report the properties of high-z hyperluminous DOGs in the ADF-S.

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Weak Lensing Analysis of the High-z Massive Galaxy Cluster SPT-CL J0205-5829 Using HST Data

  • Kim, Seojin F.;Jee, Myungkook J.
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.1
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    • pp.50.3-51
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    • 2017
  • Discovered in the South Pole Telescope Sunyaev-Zel'dovich (SPT-SZ) survey, the galaxy cluster SPT-CL J0205-5829 at z = 1.322 might be the most massive known SZ-selected galaxy cluster at z > 1.2. The SZ and X-ray combined mass estimate is $M500=(4.8{\pm}0.8){\times}10^{14}M_{\odot}$. To confirm this extreme mass, we perform weak lensing analysis of SPT-CL J0205-5829 using HST data. Our analysis produces a mass estimate consistent with the previous results obtained from non-lensing methods. In this poster, we describe details of the method including shape measurement, PSF correction, source selection, and mass estimation. We also present a two-dimensional mass map and compare this to the galaxy distribution.

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Model Reference Adaptive Control Using Non-Euclidean Gradient Descent

  • Lee, Sang-Heon;Robert Mahony;Kim, Il-Soo
    • Transactions on Control, Automation and Systems Engineering
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    • v.4 no.4
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    • pp.330-340
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    • 2002
  • In this Paper. a non-linear approach to a design of model reference adaptive control is presented. The approach is demonstrated by a case study of a simple single-pole and no zero, linear, discrete-time plant. The essence of the idea is to generate a full non-linear model of the plant dynamics and the parameter adaptation dynamics as a gradient descent algorithm with respect to a Riemannian metric. It is shown how a Riemannian metric can be chosen so that the modelled plant dynamics do in fact match the true plant dynamics. The performance of the proposed scheme is compared to a traditional model reference adaptive control scheme using the classical sensitivity derivatives (Euclidean gradients) for the descent algorithm.