• Journal of Astronomy and Space Sciences
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• v.11 no.2
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• pp.296-307
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• 1994

Using X-Window system (Motif Graphic User Interface), the AKM (Apogee Kick Motor) firing software for Koreasat which will be launched in 1995 has been developed to transfer the spacecraft from its transfer orbit, provided by the DeltaII launch vehicle, into a nearly geostationary drift orbit. The AKM firing software runs in one of two modes. In mission analysis mode, using a fixed magnitude impulsive velocity change, it provides the necessary data for planning the burn parameters. In insert mode, it uses the orbit propagator function to integrate the spacecraft state through the AKM burn. In this case, an AKM thrust profile and specific impulse are applied to the necessary data for planning the burn parameters to obtain the best possible drift orbit. The apogee burn planning simulation for orbital transfer of Koreasat has been performed using the AKM firing software. And the result of this simulation has been analyzed.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.117-119
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• 2017

The multi-stage catalytic igniter for hybrid rocket auto ignition is described in this paper. After charging the catalyst and pre-heating the first stage, the $N_2O$ was supplied at the first stage with the low mass flow rate, and then the $N_2O$ with the high flow rate was supplied into the second stage. Even though the $N_2O$ flow rate was high, it was decomposed by supplying the high temperature gas which was evolved from the $N_2O$ decomposition in the first stage. This multi-stage ignitor resulted in the decrease of the ignition time in comparison with the previous ignitor, and confirmed the possibility of $N_2O$ decomposition with the high flow rate using the multi-stage catalytic-ignition system.

• Bulletin of the Korean Space Science Society
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• 1993.10a
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• pp.12-12
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• 1993

95년 발사 예정인 무궁화위성의 궤도전이에 필요한 조정 파라미터를 계산하기 위해 원지점 모터 점화 계획 S/W를 만들어서 결과에 대해 분석해 보았다. S/W는 Mission analysis mode와 Insert mode로 구성되는데, Mission analysis mode에서는 표류궤도를 얻기 위한 점화 파라미터를 구하는 것이고, Insert mode에서는 점화 파라미터를 이용해 표류궤도를 구하는 것이다.

• Archives of design research
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• v.16 no.3
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• pp.273-280
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• 2003

Priming Effect, as a part of "Contextual Effect" is the phenomenon that pre-searched product information influences consecutive product evaluation. "Priming Effect" is different from other types of "Contextual Effects" in that pre-searched information doesn't have an direct effect on product evaluation, but an indirect effect which means that pre-searched information influences interpretation of consecutive product evaluation. On the previous theoretical background, this study investigated that how visual images can influence consumer preference and product choice, introducing concept of priming effects into the design of on-line shopping malls. This experiment adopted the digital cameras as the experimental stimulus target products and designed the individual web pages by priming the attributes of price and size. In result of analysis, the difference of product preference by priming attributes was proved to be statistically significant. In this reason, suggesting the background of commercial web page can be the significant factor in choosing products, the priming effects introduced into the design can be positively employed in online advertising.mployed in online advertising.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1999.11a
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• pp.262-270
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• 1999

본 연구에서는 정서의 처리가 어떤 과정을 거쳐 이루어지는지를 조사하였다. 정서의 우선성 효과를 알아보기 위하여 제작되었던 Murphy와 Zajonc(1993)의 실험 패러다임을 응용하여 비의식적인 수준에서의 정서점화효과와 의식적인 수준에서의 정서점화효과를 비교하였다. 정서적 경험에 있어서의 차별화를 조작하기 위하여서 실험 2에서는 실험 1에서 사용되었던 표정사진 대신 사건사진을 점화자극으로 사용하였다. 실험 1과 실험 2에서 모두 식역 이하 수준에서 점화자극을 제시하였던 경우 Murphy와 Zajonc(1993)이 발견한 점화자극으로 인한 동화의 효과가 나타났다. 원 연구자들에 따르자면 점화자극에 대한 자각은 점화자극으로 인한 동화효과를 상쇄하여야 한다. 그러나 자극제시시간을 정서적 각성이 충분히 일어나도록 길게 한 조건에서는 사건사진(실험 2)만이 정서적 동화효과를 산출하였다. 마지막으로 이런 결과들이 지니는 정서처리의 과정에 대한 시사점이 논의되었다.

• Fire Science and Engineering
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• v.27 no.6
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• pp.50-56
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• 2013

The radiation effects on the auto-ignition and extinction characteristics of a non-premixed fuel-air counterflow field were numerically investigated. A detailed reaction mechanism of GRI-v3.0 was used for the calculation of chemical reactions and the optically-thin radiation model was adopted in the simulations. The flame-controlling continuation method was also used in the simulation to predict the auto-ignition point and extinction limits precisely. As a result, it was found that the maximum H radical concentration, $(Y_H)_{max}$, rather than the maximum temperature was suitable to understand the ignition and extinction behaviors. S-, C- and O-curves, which were well known from the previous theory, were identified by investigating the $(Y_H)_{max}$. The radiative heat loss fraction ($f_r$) and spatially-integrated heat release rate (IHRR) were introduced to grasp each extinction mechanism. It was also found that the $f_r$ was the highest at the radiative extinction limit. At the flame stretch extinction limit, the flame was extinguished due to the conductive heat loss which attributed to the high strain rate although the heat release rate was the highest. The radiation affected on the radiative extinction limit and auto-ignition point considerably, however the effect on the flame stretch extinction limit was negligible. A stable flame regime defined by the region between each extinction limit became wide with increasing the fuel temperature.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.11
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• pp.3630-3638
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• 1996

An experimental study has been conducted to explore the behaviors of the radiative ignition of polymethylmetacrylate(PMMA) in a confined enclosure such as the ignition delay time, PMMA surface temperature, the ignition location and the ignition process. In addition, the effects of hot wall orientation on the ignition delay and PMMA surface temperature were studied. When the hot wall is located at the bottom, ignition delay time is the shortest. Ignition surface temperature becomes the lowest for the hot top wall case. These are due to buoyancy effect. Since the radiative heat flux of hot wall is rather lower than laser source, the ignition is considered to be controlled by the mixing process. Therefore, the ignition location, where appropriate mixture of fuel and oxygen exists, occurs near the hot wall. The flame propagates along the hot wall where there exists sufficient oxygen.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.373-376
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• 2009

A full rig combustor test and altitude ignition test were carried out for radial-annular combustor of micro turbojet engine. 11.2% total pressure loss and 99.85% of combustion efficiency were measured at design point of engine under sea level standard condition and $2{\sim}6$ of air excess ratio for ignition envelope was achieved on engine starting regime. Finally, A 30,000 ft high altitude ignition test was also performed and finally we found out that the developed radial-annular combustor is appropriate to micro turbojet engine.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2000.05a
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• pp.87-92
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• 2000

이 연구에서는 단어를 지각하게 되면 그 단어에 대한 의미가 자동적으로 활성화되고 그림표상까지도 활성화되지만, 그림을 지각하고 난 후에는 의미표상체계는 활성화되지만 단어의 지각적 표상체계는 활성화되지 않는지를 살펴보고자 하였다. 실험 1과 2에서는 지연시간을 달리하여 그림을 지각적으로 처리를 하게 한 후 단어에 대한 점화효과를 보았으며, 실험 3 에서는 그림을 개념주도적 처리를 하게 한 후 단어에 대한 점화효과 및 암묵적 기억과 재인기억을 비교해 보았다. 실험결과 지각적 판단과제에서는 조건간의 아무런 차이가 없었지만, 의미적 판단과제에서는 동일조건과 그림조건에서의 반응시간이 통제조건을 포함한 기타 조건들에서보다 빠른 것으로 나타났다. 이러한 결과는 의미적 표상체계로부터 단어의 지각적 표상체계까지의 상호작용 통로가 존재하지 않으며, 그림자극이 단어자극의 점화효과에 영향을 주는 이유는 동일한 의미적 표상체계의 활성화가 단어자극의 지각적 표상체계까지 확산되기 때문이 아니라, 그림자극에 대한 의미적 표상체계가 활성화되기 때문이라는 점을 시사한다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.05a
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• pp.353-358
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• 2008

Inha Rocket Research Institute has made the igniter that is combination of black powder and PVA polymer for ignition small rocket. But recent igniter is not satisfy because of the performance of igniter is not identified. So, we confirmed requirement of igniter by comparing of ratio of black powder and PVA through experimental method. Especially we studied with ignition temperature for propellant and stable combustion pressure that is requirements of propellant. We can know the tendency of combustion properties by ratio of oxidizer and combustion catalyst through changing of temperature and pressure of exhaust gas of igniter.