• The Journal of the Petrological Society of Korea
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• v.10 no.3
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• pp.190-201
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• 2001

Isotope Dilution Mass Spectrometry(IDMS) is one of the analytical method which uses enriched isotope spikes and analyzes the abundance of element by comparison of the spectrum between spiked mass and non-spike mass. Especially, the Thermal Ion Mass Spectrometry with isotope dilution technique (in general ID-TIMS) is the most accurate method of the chemical analysis, which enables us to obtain the data better than 1% in accuracy and precision. In IDMS, enriched isotope spike is one of the most important factor in order to obtain the best data. For rare earth elements, in general, a mixture of /sup 138/La, /sup 142/Ce, /sup 145/Nd, /sup 149/Sm, /sup 151/Sm, /sup 151/Eu, /sup 157/Gd, /sup 163/Dy, /sup 167/Er, /sup 171/Yb, and /sup 176/Lu is used as composite spike. IDMS is very useful in geochronology and REE geochemistry. Especially, it is very effective in studying the “tetrad effect” of rare earth elements in natural samples.

• Korean Journal of Applied Biomechanics
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• v.19 no.2
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• pp.359-367
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• 2009

This study was conducted to provide useful information for the scientific training of spikes and instruction, by analyzing all kinematical variants including time, distance, velocity, angle factors in spike movements of volleyball matches. The subjects were 4 foreigner players, who participated in the V-League of 2008-2009. The conclusion from this study is as follows. Time for a jumping step was .33s, and Angelko had a bit longer takeoff time than other players. In Angelko and Anderson who were leading in attack power, the whole distance of a spike motion was relatively short, less than 4m. The moment when the center of gravity reached the lowest point was when the right foot bearing weight in the jumping step was passing the left foot, and the highest point of gravity was 2.30m, which appeared just before the impact. The horizontal speed of the center of the gravity was highest as 4.19m/s at the beginning of a jumping step, and lowest at the stance phase of the fore foot just before takeoff. The vertical speed of the center of the gravity was lowest after the right foot touched the ground, and highest after the takeoff of the fore foot. Impact was 3.22m, and the highest ball speed was 28.18m/s.

• Journal of Biomedical Engineering Research
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• v.2 no.2
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• pp.83-88
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• 1981

A method of detecting abnormal spikes occuring in the EEG of subjects suffering from epilepsy is studied. The detection scheme is to take the first derivative of EEG and to determine if it exceed some threshold value. This study is focused on the digital signal processing for detecting abnormal spikes using microcomputer.

• The tire
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• s.49
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• pp.21-24
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• 1973

일본 북해도 경제본부 동계안전운전기술위원회에선 1971년 1월중에 찰황시내에서 발생한 교통사고 184건을 중심으로 동계의 안전운전의 제문제점에 대해서의 분석을 시도했다. 이하는 그 보고등에서 스노우타이어 및 스파이크타이어와 동계교통아전에 관한 부분을 특히 발췌한 것이다.

• The Science & Technology
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• v.33 no.10 s.377
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• pp.10-12
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• 2000

더 빠르게... 더 높게... 이번 시드니올림픽에서 새로운 기록을 세우기 위해 선진국들은 스포츠 과학화에 많은 투자를 했다. 피로를 줄이는 수영복, 레이저 달린 소총, 공기저항 줄이는 보디슈트, 사이클의 실크타이어 등 미국이 동원한 첨단 스포츠과학기술을 소개한다.

• Journal of Korea Technology Innovation Society
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• v.16 no.3
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• pp.630-649
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• 2013

Korea Meteorological Administration has promoted the next generation urban and rural smart weather service project. The purpose of this project is to provide the necessary information to urban and rural districts by using the subdivided meteorological information. This study attempts to assess the value of the next generation urban and rural smart weather service project by using contingent valuation method. According to estimating result, annual mean willingness to pay per household for the next generation urban and rural smart weather service project is 2,947 won.

• 한국전산유체공학회:학술대회논문집
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• 2005.10a
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• pp.293-298
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• 2005

We calculate the coordinates of an axisymmetric nozzle with a central body. This nozzle ensures a transonic flow with a plane sound surface, which is orthogonal to the symmetry axis and has a wall kink at the sonic point, The Chaplygin transformation in the subsonic part of the flow leads the Dirichlet problem for a system of nonlinear equations. The definition domain of the solution in the velocity-hodograph plane is taken as a rectangle. This enables one to obtain the nozzle with a monotonic distribution of velocity along its subsonic part. In the nonlinear differential equation, the linear Chaplygin operator for plane flows is separated, which allows the iterative calculation of the solution. The supersonic part of the nozzle is calculated under the assumption that the flow at the nozzle exit is uniform and parallel to the symmetry axis; i.e., the supersonic jet outflows to the submerged space with the same pressure. The calculation is performed by the characteristic method. The exact solution of Tricomi equation for near-sonic flows with the straight sonic line is used to 'move away' the sound plane. The velocity distribution alone the supersonic part of the nozzle is also monotonic, which ensures the absence of the boundary-layer separation and, therefore, the adequacy of the ideal-gas model. calculations show that the flow in the supersonic part of the nozzle is continuous (compression shocks are absent)

• Journal of the Korean Society of Propulsion Engineers
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• v.14 no.6
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• pp.9-16
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• 2010

The SFRJ(Solid Fuel Ram-Jet) propulsion is attractive for projectiles because of the combination of high propulsive performance and low system complexity more than conventional projectiles. The Objective of this research was to characterize the inlet aerodynamic characteristics (center-body & pitot type) in SFRJ. Diffuser static pressure & combustion chamber pressure was tested and the AoA was changed $0^{\circ}$ and $4^{\circ}$ at Mach number of 3.0 for performance estimate. The performance study of inlet was carried out with the Schlieren system and Supersonic cold-flow system. Under mach 3.0, the center-body showed twice higher total pressure recovering ratio than the pitot type. A Computational fluid dynamic solution is applied internal flow of inlet and the solutions are compared with experimental results.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.10
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• pp.27-33
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• 2016

This paper proposes a Low Noise Amplifier (LNA) with chopper stabilization technique with a sample-hold circuit. Chopper stabilization technique is effective in terms of reducing low frequency offset and flicker noise. Conventional chopper amplifier has a disadvantage in area because of using Low Pass Filter (LPF) for remove chopping spike. The proposed chopper amplifier employed sample and hold technique to decrease chopping spike instead of LPF that improves 36% in voltage damping and 11% in area.

• Aerospace Engineering and Technology
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• v.11 no.1
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• pp.27-41
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• 2012

In this paper, there is analyzed the disturbances to impact on COMS attitude and the attitude error using the received telemetries in KARI ground station during normal mode of COMS. COMS was launched successfully at Kourou, French Guiana on the 26th of June, 2010. Up to now after IOT(in-orbit test), COMS is performing well the main mission to measure meteorology and ocean during about half and one year. The disturbances to impact on COMS attitude are mostly by the Sun, by the motion of payload mirror and by the spike happened during operation of earth sensor mirror and wheel. The analysis result on the other cases happened rarely during the nominal operation, is summarized.