• 지구물리
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• 제7권1호
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• pp.11-21
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• 2004

The variation of geomagnetic field and absolute magnetic field at the geomagnetic observatory of King Sejong Station has been measured with 3-component ring core fluxgate magnetometer, proton magnetometer and D-I magnetometer. With data obtained from King Sejong Station during 2003, thediurnal and annual variations of geomagnetic field were researched and compared with those at other observatories. The deviation of daily variation of magnetic field in antarctica decreased gradually during winter season due to sun effect. The rates of componental annual variation of magnetic field at King Sejong Station were calculated using the least-square method under the assumption that the annual variation of magnetic field is linear. The rates are -55.93 nT/year in horizontal intensity, -0.87 min./year in declination, 58.30 nT/year in vertical intensity, and -69.85 nT/year in total intensity of magnetic field. A remarkable variation was caused by the magnetic storms occurred on 29~30 October, which were so powerful that the variation was observed in mid latitudes as well as high latitudes. The values of variation are generally 1500 2000 nT in Antarctica including King Sejong Station, 350 500 nT in East Asia. The measurement of absolute magnetic field shows that ring core fluxgate magnetometer has relatively large error range under cold temperature.

• 천문학논총
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• 제15권spc2호
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• pp.15-20
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• 2000

The geomagnetic measurements on the Korean Territory began in 1918 in the Incheon (Zinsen in Japanese pronunciation) Observatory of which the annual means of total magnetic field intensity, declination, and inclination still remain for 1918-1944. From 1970s, the National Geography Institute (NGI) and the Radio Research Laboratory (RRL) have tried independently to measure the geomagnetic field continuously. The RRL as the result of such efforts has installed 3 geomagnetic observatories, the first in Icheon and the second in Yongin in 1996, and the third in Jeju in 1997. From 1992, the Korea Institute of Geology, Mining and Materials (KIGAM) has tried also to measure the geomagnetism and as the result they have installed 2 geomagnetic observatories, one in Daejeon in 1998 and the other in Gyeongju in 2000. Nowadays, the RRL and the KIGAM collect the measured data into their own main computers by telecommunication in real time. The two institutions will cooperate in near future to link the two geomagnetic data bases so that the whole set of geomagnetic data measured on Korean Territory could be provided to the end users in Korea.

• 한국항공우주학회지
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• 제39권12호
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• pp.1133-1140
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• 2011

기존의 홀추력기 개념 설계는 비용이 많이 소요되며 과거의 데이터에 기반한 실험적 방법에 근거하고 있다. 본 연구에서는 이러한 홀추력기의 설계 과정을 향상시키기 위해 최근 제안된 수치적 방법에 근거하여 설계 목적에 적합한 설계 공간을 설정하고 이에 대한 설계 공간 탐색을 수행하였다. 설계 공간 탐색의 결과를 통해 기본적으로 주어진 설계 공간에 대한 성능 범위를 결정하였으며 성능간의 관계를 분석하였다. 세부적인 결과 분석을 통해 홀추력기의 주요한 설계 변수로는 양극에서의 질량유량과 방전전압임을 도출하였다.

• 천문학회보
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• 제42권2호
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• pp.89.2-89.2
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• 2017

Korea Pathfinder Lunar Orbiter (KPLO) is a first Korean Lunar exploration mission. KPLO is equipped with four payloads in Korea and one payload in United States. KMAG is one of Korean payloads to measure the Moon's magnetic field. Moon has a no dipole magnetic field such as earth's global magnetic field. But there are many curious crustal magnetic anomalies. these features still do not well understood. This is a main scientific objective of KMAG payload and the study of space environment around moon is a second objective. KMAG has three magnetometers which are mounted in the edge of the 1.2 meter boom. This paper shows a KMAG's requirements, instrument description, and a preliminary function test results.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.648-653
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• 2003

Optimized recovery of heavy minerals from the near shore sands of Korean Yellow Sea was investigated using physical processing technologies such as gravity concentration and magnetic separation. The head samples were subjected to the three stages effective separation; Head sample was first treated by a spiral separator to recover rough heavy mineral concentrates, which are contained minerals like ilmenite, zircon and rare earth minerals. Much higher beneficiation processes were subsequently taken by wilfley table and magnetic separation according to their magnetic field responses. Heavy minerals were effectively recovered by wilfley table and subsequent recleaning of heavy minerals by magnetic separations was conducted. Qualitative and relative-quantitative analyses of their constituent elements were doing using XRD and XRF.

• Investigative Magnetic Resonance Imaging
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• 제19권1호
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• pp.52-55
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• 2015

Supradiaphragmatic liver is a rare condition. Establishing an accurate preoperative diagnosis is difficult. Operative exploration is necessary to differentiate this lesion from intrathoracic masses, such as a pleural based tumor, diaphragmatic tumor and peripheral lung tumor. However, with the aid of the hepatocyte-specific magnetic resonance imaging contrast agent, gadoxetic acid (Gd-EOB-DTPA), functional hepatocytes in the lesion can be identified in the hepatobiliary phase, potentially allowing an accurate and non-invasive diagnosis. We report a case of supradiaphragmatic liver diagnosed by Gd-EOB-DTPA-enhanced magnetic resonance imaging.

• 한국초전도ㆍ저온공학회논문지
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• 제25권2호
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• pp.1-4
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• 2023

Over the past decade, the exploration of high-temperature superconductivity and the discovery of a wide range of exotic superconducting states in Fe-based materials have propelled condensed matter physics research to new frontiers. These materials exhibit intriguing phenomena arising from their multiband electronic structure, strongly orbital-dependent effects, extremely small Fermi energy, electronic nematicity, and topological aspects. Among the various factors influencing their superconducting properties, high magnetic fields play a crucial role as a control knob capable of disrupting the subtle balance between the spin, charge, lattice, and orbital degrees of freedom, leading to the emergence of various exotic superconducting states. In this review, we provide an overview of the current understanding of the exotic superconducting states observed in Fe-based superconductors, with a particular focus on FeSe and Sr₂VO₃FeAs, under the influence of high magnetic fields.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2011년도 학술대회 및 정기총회
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• pp.161-162
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• 2011

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2010년도 학술대회 초록집
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• pp.181-184
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• 2010

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2010년도 학술대회 초록집
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• pp.151-152
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• 2010