• Journal of Astronomy and Space Sciences
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• 제35권2호
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• pp.111-117
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• 2018

A previous exo-terrestrial life-detecting experiment, which was conducted on Mars, sought to detect the products of glucose metabolism, the most common biological process on Earth (Viking biological experiment). Today, glucose metabolism is not considered the universal process of life survival. As NASA plans to launch an orbiter mission in the near future (2020s, the Clipper) and ultimately conduct a lander mission on Europa, a detection experiment that can give broader information regarding habitability is highly required. In this study, we designed a life-detecting experiment using a more universal feature of life, the amphipathic molecular membrane, theoretically considering the environment of Europa (waterdominant environment). This designed experiment focuses on finding and profiling hydrophobic cellular membrane-like microstructures. Expected results are given by conceptual data analysis with plausible hypothetical samples.

• 대한가정학회지
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• 제26권3호
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• pp.13-31
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• 1988

• 한국의류학회지
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• 제8권2호
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• pp.27-40
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• 1984

Die Geschichte des Kostums steht in unmittelbarem odor mittelbarem Zusammenhang mit der allgemeinea historischen Entwicklung derjenigen Lander und sozialen Schichten, die das kulturclle Gesicht und damit auch die Entwicklung der Mode einer Epoche bestimmen. Im 19. Jahrhundert war das Burgertum in Europa die herrschende soziale Schicht und daher auch modisch tonangebend. Die Mode des Burgertums zeigte demokratisierende Tendon-zen: Vereinfachung der Ausstattung und der Formen, wobei sich die Proportionen der Kleidung so gut wie moglich den des Korpers anpaBten. Die Herrenmode beugte sich zunehmend den For-derungen nach ZweckmaBigkeit; dab galt zumindest fur den Tagesanzug, der immer mehr zum Arbeitsanzug wurde und sick damit der Mannerkleidung der arbeinden Schicht annahrte. Die Industrialisierung trug ebenfalls dazu bei, daB die modischen und sozialen Previlegien in der Kleidung sich verminderten : die Textil-und Konfektionsindustrie muBte sich zwangs-laufig auf die Bedurfnisse der Massen und auf deren Wunsch einstellen. In der Herrenmode setzte sich die Tendenz zu funktionaler Einfachheit und Gradlinigkeit durch, d.h. funktional uberflussige Teile wie z.B. die Vielzahl der Kragen, Knopfreihen, uberlange SchoBe verschwanden ; an die Stelle der Farbenfreude trat ein einfaches, einhei-tliches Grau, Schwarz, Blau und Braun. Diese Vereinfachung wurde zum Ausdruck der zunehmenden Demokratisierung, wurde aber zugleich auch Voraussetzung fur eine neue Differnzierung des KlassenbewuBtseins. Zum Statussymbol wurden die auffalliges Erscheinen vermeidende Eleganz und das Arrangement der einzelnen Kleidungsstucke zu einem har-monischen Ganzen; elegante Kleidung weist ihren Trager aus als Kenner des Modetrends und damit als zugehorig zum Kreis der modeavancierten Schicht. Diese Ambivalenz bestimmt auch die Mode des 20. Jahrhunderts.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2003년도 한국우주과학회보 제12권2호
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• pp.47-47
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• 2003

Analytical formulae are presented to approximate the evolution of the semi major axis, the maneuver time, and the final mass fraction for low thrust orbital transfers with circular initial orbit, circular target orbit, and constant thrust directed either always along or always opposite the velocity vector. For comparison, the associated results for high-thrust transfers, i.e. the two-impulse Hohmann transfer, are summarized. All results are implemented in a computer code designed to analyze planar planetary and interplanetary space missions. This implementation yields fast and reasonably accurate approximations to trajectory performance boundaries. Consequently, the approach can provide trajectory analysis for each spacecraft configuration during the conceptual space mission design phase. As an example, a mission from Low-Earth Orbit (LEO) to Jupiter's moon Europa is analyzed.

• Wind and Structures
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• 제3권1호
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• pp.41-58
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• 2000

According to research currently developed by several authors (including the present ones) a multimode approach to the aeroelastic instability can be appropriate for suspension bridges with very long span and so with close natural frequencies. Extending that research, this paper deals in particular with: i) the role of along-wind modes, underlined also by means of the flutter mode representation; ii) the effects of a variation of the mean wind speed along the span. A characterisation of the response in the time domain by means of an energetic approach is also discussed.

• 천문학논총
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• 제38권2호
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• pp.37-57
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• 2023

"Are we alone in the universe?" is the fundamental question of mankind. To search for the life signatures in the universe, there have been a lot of researches and space explorations, especially in our solar system. In this review paper, we introduce the definition and characteristics of the "biosignature". The current situations and future plans for searching for biosignatures in our solar system are reviewed, especially at Venus, Mars, and Ocean Worlds such as Europa and Enceladus where life signatures are more likely to exist than in other places in the solar system. Finally, we discuss the opportunities and strategies for the Korean scientific society to participate in searching for biosignatures in the solar system.

• Journal of Microbiology and Biotechnology
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• 제8권1호
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• pp.8-13
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• 1998

Animal cells in culture typically convert most of the glucose they consume into lactate. The accumulation of lactate, however, is commonly cited as one of the factors that inhibit cell growth and limit the maximum cell concentration that can be achieved in culture. The specific production of lactate and the amount of glucose converted to lactate can be reduced when cells are grown in a fed-batch culture in which the residual glucose concentration is maintained at low levels. Such a fed-batch culture was used to grow and adapt hybridoma cells into a low-lactate-producing state before changing into continuous culture. The cells reached and maintained a high viable cell concentration at steady state. In a similar manner, cells that were initially grown in batch culture and a glucose-rich environment reached a steady state with a cell concentration that is much lower. The feed composition and dilution rates for both cultures were similar, suggesting steady state multiplicity. From a processing perspective the desired steady state among those is the one with the least metabolite production. At such seady state nutrient concentration in the feed can be further increased to increase cell and product concentrations without causing the metabolite inhibitory effect typically seen in a cell culture. Controlling cell metabolism in a continuous culture to reduce or eliminate waste metabolite production may significantly improve the productivity of mammalian cell culture processes.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제54권12호
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• pp.592-600
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• 2005

In this paper, a low loss magnetic levitation(Maglev) system is suggested and tested. The suggested Maglev system includes four hybrid magnets which consist of permanent magnet and coil. In the steady state, the levitated module system can be supported by attraction force generated by permanent magnet. The coil current controls only dynamic loads due to external disturbances. The module systems are designed by using finite element method(FEM) software tools such as MAXWELL and ANSYS. Also, digital control systems are designed to keep the magnet airgap at a constant value. The control systems include a VME(versa module europa)-based CPU(central processing unit) board, AD(analog to digital) board, PWM(pulse width modulation) board, 4-quadrant chopper, and sensors. In order to estimate the vertical velocity of the magnet, we use second order state observer with acceleration and gap signals as input and output signals, respectively. The characteristics of the suggested low loss Maglev system are demonstrated by experimental results showing coil current of 0A in the steady state of 3m airgap and performance specifications are satisfied for reference gap and force disturbance.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 D
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• pp.2239-2241
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• 2003

A new RF control system of Pohang Accelerator Laboratory (PAL) storage ring is a subsystem upgraded PAL control system, which is based upon Experimental Physics and Industrial Control System (EPICS). There are 5 control components, Low Level RF System (LRS), Klystron System, Circulator System, Cavity System, Local Cooling Water System (LCW) at the storage ring of PAL. The new RF control system for the storage ring has been under development for one years, first versions of individual VME (Versa Module Europa) Input/output modules under construction and system integration begun. In this system, VMEbus-based hardware is widely used for front-end controllers (FDS), Input/output controller (IOC). A number of Programmable Logic Controller (PLC) and SUN workstations are also used for Operator Interfaces (OPI) in the control system. This paper describes the development VME I/O module to the new control system and how the design of this new system.

• 우주기술과 응용
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• 제3권1호
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• pp.1-25
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• 2023

In this paper, I briefly introduce recently terminated, current, and future scientific spacecraft missions for in situ and remote-sensing observations of Earth's and other planetary magnetospheres as of February 2023. The spacecraft introduced here are Geotail, Cluster, Time History of Events and Macroscale Interactions during Substorms / Acceleration, Reconnection, Turbulence, and Electrodynamics of the Moon's Interaction with the Sun (THEMIS / ARTEMIS), Magnetospheric Multiscale (MMS), Exploration of energization and Radiation in Geospace (ERG), Cusp Plasma Imaging Detector (CuPID), and EQUilibriUm Lunar-Earth point 6U Spacecraft (EQUULEUS) for recently terminated or currently operated missions for Earth's magnetosphere; Lunar Environment Heliospheric X-ray Imager (LEXI), Gateway, Solar wind Magneto-sphere Ionosphere Link Explorer (SMILE), HelioSwarm, Solar-Terrestrial Observer for the Response of the Magnetosphere (STORM), Geostationary Transfer Orbit Satellite (GTOSat), GEOspace X-ray imager (GEO-X), Plasma Observatory, Magnetospheric Constellation (MagCon), self-Adaptive Magnetic reconnection Explorer (AME), and COnstellation of Radiation BElt Survey (CORBES) approved for launch or proposed for future missions for Earth's magnetosphere; BepiColombo for Mercury and Juno for Jupiter for current missions for planetary magnetospheres; Jupiter Icy Moons Explorer (JUICE) and Europa Clipper for Jupiter, Uranus Orbiter and Probe (UOP) for Uranus, and Neptune Odyssey for Neptune approved for launch or proposed for future missions for planetary magnetospheres. I discuss the recent trend and future direction of spacecraft missions as well as remaining challenges in magnetospheric research. I hope this paper will be a handy guide to the current status and trend of magnetospheric missions.