• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.66.2-66.2
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• 2017

The Korea Astronomy and Space Science Institute plans to develop a coronagraph in collaboration with National Aeronautics and Space Administrative (NASA) and install it on the International Space Station (ISS). The coronagraph is an externally occulted one stage coronagraph with a field of view from 2.5 to 15 solar radii. The observation wavelength is approximately 400 nm where strong Fraunhofer absorption lines from the photosphere are scattered by coronal electrons. Photometric filter observation around this band enables the estimation of 2D electron temperature and electron velocity distribution in the corona. Together with the high time cadence (< 12 min) of corona images to determine the geometric and kinematic parameters of coronal mass ejections, the coronagraph will yield the spatial distribution of electron density by measuring the polarized brightness. For the purpose of technical demonstration, we intend to observe the total solar eclipse in 2017 August for the filter system and to perform a stratospheric balloon experiment in 2019 for the engineering model of the coronagraph. The coronagraph is planned to be installed on the ISS in 2021 for addressing a number of questions (e.g. coronal heating and solar wind acceleration) that are both fundamental and practically important in the physics of the solar corona and of the heliosphere.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.11
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• pp.1305-1310
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• 2014

In this paper, the new integrated crane monitoring system that complemented the point at issue for existing crane monitoring system is implemented. The Implementing monitoring system based on wireless communication system, consist of a measuring system of total load currents of main circuit breaker, a temperature and vibration measuring system with temperature sensors and vibration sensors for monitoring an oil and bearing of a main decelerator, a temperature measuring system with temperature sensors of a main motor bearing, and sensors for fire monitoring of an entire electrical space. The measured data from these sensors transmit main controller which is located in external location. Then the Integrating monitoring system is implemented and is performed the performance test to performing diagnosis of motors of a crane.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.1018-1021
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• 2003

This dissertation is reference to measure visual information about the configuration of magnetic field automatically and materialize the new magnetic field mapping system for the rapid and clear measure by using of the mediocrity orthogonal robot in the three- dimensional space required the measure of magnetic field concurrently. The measuring sensor is composed to be available for the measure of three-dimensional direction of magnetic field by vertically conjoining each of three hall sensors utilized of the hall effect and installed Gaussmeter, which is devised to receive the sensor result and the robot controller, away from the measuring robot in order to minimize the affection of magnetic field. Also, the controller and Gaussmeter are composed of Use interface, RS-232C and IEEE-488.2 communication. Interface system is written in NI's LabVIEW and composed to be able to set up a measuring area, the measuring number of times, two and three-dimensional graph, the velocity of robot and the magnetic field distribution graph of each element by inputting parameters. The materialized magnetic field mapping system expert the collection of the data easily and the effect of utilizing data.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.5
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• pp.411-429
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• 2022

Instrumentations are essential in NATM tunnels, however measuring instruments are installed and applied without performance verification procedures due to insufficient research on methods, procedures, regulations, etc. to verify the reliability of the measuring instruments. In this study, domestic and foreign regulations relating to the verification and calibration of instruments were investigated and necessities for accreditation standards were proposed. In order to identify the causes of the defects, an external inspection was performed on rock bolt stressmeter and rod extensometer, which are measuring instruments with relatively complex structures. For verifying the performance of these instruments, verification devices were developed that can load step-by-step and the causes of defects were identified in measuring instruments of nine domestic manufacturers. Through the performance test, a number of measuring instruments were found to be defective. It was important to test the performance of the instruments in the state of a finished product and accordingly performance inspection methods and procedures were proposed. The results of this study are expected to help preparing related regulations for verifying instrument performance and selecting instruments in the field.

• Structural Engineering and Mechanics
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• v.33 no.2
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• pp.257-260
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• 2009

• Communications of the Korean Mathematical Society
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• v.23 no.4
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• pp.541-548
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• 2008

For a completely bounded linear maps between operator spaces, we introduce numbers which measure the degree of injectivity and subjectivity. The number measuring the injectivity is an operator space analogue of the minimum modulus of a linear map in normed spaces.

• Korean Institute of Interior Design Journal
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• v.21 no.1
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• pp.203-210
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• 2012

Since a private museums started in Europe 17C, many private museums established for high-class people like aristocrats to collect and to keep art works and to appreciate for limited members. After the French Revolution in 18C, the publicity became an important social issue through all European regions, and the museum gradually changed into public ones. Like that, as the concept of museum changed, its social role as well as its function was also changed. The concept of collection and display or preservation changed into the concept of exhibition and appreciation featuring the publicity. With the year-round exhibition, a classical concept, the planned-exhibition, a new active concept set as an important factor for a museum's projects. The latter concept embraces new social issues. Therefore as the space for planned-exhibitions reflecting social issues every season was needed, a museum sets its planned-exhibition space with the changeability, and gradually expands this kind of space in size. It is expected that planned-exhibition spaces characterized as the changeability may give some changes on the flow of a museum's overall space, and may have substantial influences on the flow. To recognize the changes in a planned-exhibition space's influence on the museum, this study selected some national, public museums having the planned-exhibition space, and investigated their influences on each museum's overall space structure through the analysis on space syntax. This study assumed the change of planned-exhibition space as the changes in the number of convex spaces, and measured it. And to understand the planned-exhibition's changes on a museum's overall spaces, such changed assumed as the numeric changes in convex spaces and measured them. In addition, the numeric changes's influence on the overall space structure was analyzed by measuring the overall space's average integration level. Through the above two factors, the 3 research methodologies and analyzed results were drawn out.

• Journal of Astronomy and Space Sciences
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• v.30 no.1
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• pp.49-58
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• 2013

ARGO-M is a satellite laser ranging (SLR) system developed by the Korea Astronomy and Space Science Institute with the consideration of mobility and daytime and nighttime satellite observation. The ARGO-M optical system consists of 40 cm receiving telescope, 10 cm transmitting telescope, and detecting optics. For the development of ARGO-M optical system, the structural analysis was performed with regard to the optics and optomechanics design and the optical components. To ensure the optical performance, the quality was tested at the level of parts using the laser interferometer and ultra-high-precision measuring instruments. The assembly and alignment of ARGO-M optical system were conducted at an auto-collimation facility. As the transmission and reception are separated in the ARGO-M optical system, the pointing alignment between the transmitting telescope and receiving telescope is critical for precise target pointing. Thus, the alignment using the ground target and the radiant point observation of transmitting laser beam was carried out, and the lines of sight for the two telescopes were aligned within the required pointing precision. This paper describes the design, structural analysis, manufacture and assembly of parts, and entire process related with the alignment for the ARGO-M optical system.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.4
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• pp.350-356
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• 2005

We report the space charge and the surface potential of the interface between metal and copper(Ⅱ)-phthalocyanine(CuPc) thin films by measuring the microwave reflection coefficients S/sub 11/ of thin films using a near-field scanning microwave microscope(NSMM). CuPc thin films were prepared on Au and Al thin films using a thermal evaporation method. Two kinds of CuPc thin films were prepared by different substrate heating conditions; one was deposited on preheated substrate at 150。C and the other was annealed after deposition. The microwave reflection coefficients S/sub 11/ of CuPc thin films were changed by the dependence on grain alignment due to heat treatment conditions and depended on thickness of CuPc thin films. Electrical conductivity of interface between metal and organic CuPc was changed by the space charge of the interface. By comparing reflection coefficient S/sub 11/ we observed the electrical conductivity changes of CuPc thin films by the changes of surface potential and space charge at the interface.

• Carbon letters
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• v.15 no.3
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• pp.180-186
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• 2014

This study highlights a novel method and mechanism for the rapid and effective milling of carbon fibers (CFs) in silicon carbide (SiC) powder, and also the dispersion of CFs in SiC powder. The composite powders were prepared by chopping and exfoliation of CFs, and ball milling of CFs and SiC powder in isopropyl alcohol. A wide range of CFs loading, from 10 to 50 vol%, was studied. The milling of CFs and SiC powder was checked by measuring the average particle size of the composite powders. The dispersivity of CFs in SiC powder was checked through scanning electron microscope. The results show that the usage of exfoliated CF tows resulted in a rapid and effective milling of CFs and SiC powder. The results further show an excellent dispersion of CFs in SiC powder for all CFs loading without any dispersing agent.