• Title/Summary/Keyword: Field observation

Search Result 1,639, Processing Time 0.035 seconds

Petrogenetic Significance of the New Petrogenetic Grid (2000) Compared with Synthetic System and Theoretically Computed Grid

  • Ahn, Kun-Sang;Nakamura, Yasuo;Shin, In-Hyun
    • Journal of the Korean earth science society
    • /
    • v.23 no.1
    • /
    • pp.105-111
    • /
    • 2002
  • The observation of the new biotite isograd (chlorite + chloritoid = andalusite + biotite) in the Mungyong coal field requires the modification of Harte and Hudson's (1979) metapelite grid which eliminates the stability field of staurolite + cordierite assemblages. The newly proposed metapelite grid by Ahn and Nakamura (2000) can define more properly the isograd reaction observed from nature. We discuss first topological interrelations between synthetic system (FASHO-, KFASHO-, KFMASH system) on an isobaric section at 2kbar, where phase relations are well constrained. The following discussion is concentrated on the topological relations between stable reactions. At the last, we discuss the petrogenetic significance of the Ahn's petrogenetic grid compared with theoretically computed grids. Ahn's petrogenetic grid is consistent with synthetic and natural system, and is one of the excellent example of KFMASH approximation in metapelite.

Annealing-temperature Dependent Characteristics of PLZT Thin Films on ITO Coated Glass (ITO 기판에 제작된 PLZT 박막의 소성온도에 따른 특성)

  • Choi, Hyung-Wook;Jang, Nak-Won;Park, Chang-Yub
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.11 no.2
    • /
    • pp.128-132
    • /
    • 1998
  • 2/65/35 PLZT stock solution prepared by Sol-Gel processing was spin-coated on ITO coated glass and annealed by RTA(Rapid Thermal Annealing). The crystal structure of films was reported based on the observation of crystallization process and microstructure of the film fabricated at different fabrication condition. Films were crystallized into rhombohedral structure by annealing at $750^{\circ}C$ for 5 min. As the annealing temperature increased, the size of rosette structure of the films was grown up from $2.4{\mu}m$ to $15{\mu}m$, dielectric constant was increased, coercive field was decreased 33.82 kV/cm, remnant polarization was increased to 39.84 ${\mu}C/cm^2$ and Optical transmittance was decreased.

  • PDF

Influence of Water Absorption and Charge Formation in PCB (PCB 절연체에서 전하 형성과 수분 흡수의 영향)

  • Goo, Jung-Hyun;Choi, Yong-Sung;Lee, Kyung-Sup
    • Proceedings of the KIEE Conference
    • /
    • 2008.07a
    • /
    • pp.2307-2308
    • /
    • 2008
  • We observed internal space charge behavior for two types of epoxy composites under dc electric fields to investigate the influence of water at high temperature. In the case of glass/epoxy specimen, homocharge is observed at water-treated specimen, and spatial oscillations become clearer in the water-treated specimens. Electric field in the vicinity of the electrodes shows the injection of homocharge. In aramid/epoxy specimens, heterocharge is observed at water-treated specimens, i.e. negative charge accumulates near the anode, while positive charge accumulates near the cathode. Electric field is enhanced just before each electrode. In order to further examine the mechanism of space charge formation, we have developed a new system that allows in situ space charge observation during ion migration tests at high temperature and high humidity. Using this in situ system.

  • PDF

Estimation of Time Mean Velocities from NOAA Satellite 557 Data (NOAA위성의 557자료를 이용한 시간평균유속의 추정)

  • 이태신;정종률
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.7 no.3
    • /
    • pp.241-247
    • /
    • 1995
  • A time mean surface velocity field was estimated from AVHRR/SST in the Korea Strait. Time duration of SST data set was not different from tidal period and tidal elimination was investigated. The velocity field was estimated by inverse method and compared with results of ADCP observation and results of Odamaki(1989). In accordance with results. tidal component was eliminated partially in case that there were a little difference between total time interval of 557 data set and tidal period.

  • PDF

OVERVIEW OF KOMPSAT APPLICATION PRODUCT VALIDATION SITE AND THE RELATED ACTIVITIES

  • Lee, Kwang-Jae;Youn, Bo-Yeol;Kim, Duk-Jin;Kim, Youn-Soo
    • Proceedings of the KSRS Conference
    • /
    • 2007.10a
    • /
    • pp.122-125
    • /
    • 2007
  • In recent years, there has been an increasing demand for improved accuracy and reliability of Earth Observation Satellite (EOS) data. Most of the data users in the field of remote sensing require understanding of product accuracy and uncertainty. Especially, EOS application products should be validated for practical application in the field. In order to evaluate the availability and applicability of application products, it will be necessary to establish a systematic validation system including techniques, equipments, ground truth data, etc. The Product Validation Site (PVS) for generation and validation of KOMPSAT application products was designed and established with various in-situ equipment and dataset. This paper presents the status of PVS and summarizes some results from experiment studies at PVS.

  • PDF

A Sutdy on the Water Quality Management using Fllow Paddy (유휴농지를 이용한 수질관리방안 연구)

  • Kim, Hyung-Joong;An, Yeul;Kim, Sun-Joo;Kim, Phil-Shik
    • Proceedings of the Korean Society of Agricultural Engineers Conference
    • /
    • 2005.10a
    • /
    • pp.485-489
    • /
    • 2005
  • Fallow paddy has been increased in disadvantageous farming condition area because of importation of foreign agricultural products, labor cost and the imbalance between farming cost and agricultural products price since 1990. The fallow paddy that has gradually increased needs to be prevented from the devastation by weed breeding for re-cultivation. In this study, two fallow paddies that manage with different water depth from the experimental field were selected for observation, and analysis of water quality, water balance and plant body change. The managed fallow paddy was more effective in water quality purification and plants growth control than non-managed fallow paddy. And the fallow paddy managed with a some degree water depth was the most effective field on weed control.

  • PDF

Variations of Geomagnetic Field in Korea (우리나라의 지자기장의 변화)

  • 윤홍식
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.17 no.4
    • /
    • pp.331-338
    • /
    • 1999
  • This paper describes the variations of geomagnetic field by analyzing the geomagnetic observation data, which spanned the period from 1918 through 1944 and the global geomagnetic model in Korea. Geomagnetic data observed at Incheon in the period of 1918~1944 and global geomagnetic model (IGRF-95) were obtained from the World Geomagnetic Data Center. In this study, the variations of geomagnetic declination is estimated as $1^\circ{50'}$ from 1918 to 2000 and the variation rate is given as the nearest 1'20"/yr. The total variation of inclination is about 38' for 82 years and the variation rate is estimated as the nearest 27"/yr."/yr.;/yr.

  • PDF

MURO - Mangpo high school Unmanned Robotic Observatory

  • Kim, Hyunjong;Pak, Soojong;Kim, Youngjong
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.41 no.1
    • /
    • pp.52.1-52.1
    • /
    • 2016
  • We introduce the characteristics and performance of the 0.25m telescope at Mangpo high school Unmanned Robotic Observatory (MURO) which was established in Yangpyeong-gun, Gyeongi-do, KOREA in 2015 January. MURO system included Astrohaven 2.1m non-rotation fiberglass clamshell dome, Paramount MEII mount, Takahashi CCA 0.25m wide field telescope, FLI PL 16803 4K CCD with 7-positions filter wheel system, all sky camera and point grey wide field camera, IR 4 chanel heat sensor camera for security, DAVIS realtime weather cast, and power controled by ARS system. All control softwares are from off-the-shelf products based on Windows 7 OS to be easily operated and maintained. We expect to perform variety of science programs ranging from supernovae follow-up observation to narrow band imaging survey as well as science class activities at Mangpo high school.

  • PDF

Observation of optical vortices in speckle field (스펙클 위상도에서 광소용돌이 현상의 관측)

  • 강전웅;윤해영;홍정기
    • Proceedings of the Optical Society of Korea Conference
    • /
    • 2000.08a
    • /
    • pp.124-125
    • /
    • 2000
  • Since Nye and Berry$^{(1)}$ showed that in free space the electromagnetic field could contain stable, propagating phase singularities termed "dislocations", optical dislocations have been extensively investigated in nonlinear optics and laser physics. As the wave propagates, the lines of constant phase surrounding a dislocation trace out a spiral in space or in time. So these phase singularities are now usually referred to as optical vortices. Baranova and her co-workers$^{(2)}$ have shown that in fully developed speckle patterns, there is, one optical vortex accompanying each speckle spot on average. Among these vortices there are networks in phasemap because only one phase is to be assigned in one point except optical dislocations having zero amplitude. Freund et al.$^{(3)}$ have been studied optical dislocation networks and simulations are compared with experimental results. (omitted)

  • PDF

Position Detection of a Capsule-type Endoscope by Magnetic Field Sensors (자계 센서를 이용한 캡슐형 내시경의 위치 측정)

  • Park, Joon-Byung;Kang, Heon;Hong, Yeh-Sun
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.24 no.6
    • /
    • pp.66-71
    • /
    • 2007
  • Development of a locomotive mechanism for the capsule type endoscopes will largely enhance their ability to diagnose disease of digestive organs. As a part of it, there should be provided a detection device of their position in human organs for the purpose of observation and motion control. In this paper, a permanent magnet outside human body was employed to project magnetic field on a capsule type endoscope, while its position dependent flux density was measured by three hall-effect sensors which were orthogonally installed inside the capsule. In order to detect the 2-D position data of the capsule with three hall-effect sensors including the roll, pitch and yaw angle, the permanent magnet was extra translated during the measurement. In this way, the 2-D coordinates and three rotation angles of a capsule endoscope on the same motion plane with the permanent magnet could be detected. The working principle and performance test results of the capsule position detection device were introduced in this paper showing that they could be also applied to 6-DOF position detection.