• Journal of the Korean Society of Propulsion Engineers
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• v.4 no.2
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• pp.1-5
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• 2000

The silane compounds as a coupling agent have been used in the propellant in order to enhance the mechanical property and lower the viscosity. They showed great effects in the PEG propellant. In PCP propellant, however, the silane compounds not only made a severe cure problem but also deteriorated the mechanical property. In this study, TESPN as a silane compound was applied in PEG and PCP binder for finding above factors. The main reason was that the main chains of PCP were broken due to the trans-esterification reaction of ester groups in PCP and alchol which was produced by reacting silane compounds and moisture in the solution of liquid binder.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.2
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• pp.9-17
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• 2007

The performance test of recirculation line in propellant feeding system was carried out. Liquid oxygen was used as cryogenic propellant and helium was used as recirculation promotion gas. Tests were done in cases at atmospheric pressure and at pressure of 4 barg in the ullage space of propellant tank. Liquid oxygen recirculation flowrate with helium injection flowrate and temperature distribution along the line were measured. There was appropriate helium injection flowrate for gas-lift recirculation system. Test data were used to make calculation program by test data correlation method. In this paper the procedure of calculation was presented and the results were compared to test data.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.89-94
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• 2010

Fuselage propellant feeding system should supply propellants to engine with required flow rate, temperature and pressure. Propellant vibration in engine and feeding line changes feeding characteristics, and frequently inhibits to satisfy the required feeding requirements. Sloshing and POGO vibration are known to be the major vibration phenomena. Concerning sloshing and POGO, vehicle control and structural dynamics aspects are extensively studied, whereas, its effect on propellant feeding performance is not clearly understood. This paper focuses on the deviation of required feeding performance due to propellant vibration. Overall characteristics of propellant vibration and its effect on propellant supply to engine are reviewed and control mechanism for suppressing vibration is introduced.

• Environmental engineer
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• v.23 s.239
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• pp.58-61
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• 2006

• Information and Communications Magazine
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• v.29 no.1
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• pp.17-22
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• 2011

최근의 글로벌 IT시장은 HW 중심에서 SW 모바일 중심으로 급속히 변화하고 있으며, SW, PC, 휴대폰 등 비교적 명확했던 IT 경계가 사라지고 융합화 되고 있어, SW산업은 IT 산업 전체의 경쟁력을 좌우하는 기반산업으로서 그 역할이 확대되고 있다. 그러나, 2010년말 국내 SW시장은 세계시장의 2.0%(임베디드SW 포함)에 불과하며, 적지 않은 문제점을 가지고 있다. 첫째, SW시장질서가 공정하지 못하며 생태계가 왜곡되어 있다. 둘째, 인력 기술 창업 등 SW산업의 기초체력이 미흡하다. 셋째, 임베디드시스템 경쟁력 부족으로 융합 시장이 활성화되어 있지 못하다. 넷째, 협소한 국내 시장을 넘어 글로벌 시장에 도전하는 기업가 정신이 부족하다. 이러한 상황에서 젊은 인재와 SW전문기업이 글로벌 시장에 도전하고 성공할 수 있는 생태계를 조성하기 위해 2011년 10월 27일 제102차 비상경제대책회의에 "공생발전형 SW생태계 구축 전략"이 상정되어 확정되었다. 동 전략의 기본 방향은 1) IT서비스 대기업 중심의 시장 질서를 전문 중소기업 중심으로 전환, 2) 패키지 SW 임베디드SW를 우리 경제의 사활이 걸린 분야로 선정하고, 핵심경쟁력 제고여건 조성에 있다. 이를 위한 추진과제로 SW공정 거래 질서 확립, SW기초체력강화, SW융합 활성화가 추진될 계획이며, 또한 정책의 지속적인 수행을 위한 재원 마련 방안 및 추진 체계를 확보함으로써, 공생발전형 SW생태계 구축의 새로운 전기가 마련될 것이다.

• Journal of the Korean Society of Propulsion Engineers
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• v.4 no.4
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• pp.50-58
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• 2000

Burning rate of the matrix propellant($r_{sb}$) and burning rate along the metal wire($r_w$) were measured and analyzed for the HTPB/AP/Al propellant embedded with Ag wire($\phi$0.15mm) according to weight % of RDX(0~20%). Variation of burning rate increment ratio($r_w$/$r_{sb}$) and pressure exponent(n) was studied for the nitramine propellant having 10% RDX embedded with three kinds of metal(Ag, Cu, and Ni-Cr) of which diameter range is between 0.1~0.6mm. Maximum burning rate increment ratio of the nitramine propellant embedded with Ag wire($\phi$0.1mm) was 5.94 at $20^{\cire}C$, 1000 psia, 16.4% faster than that of HTPB/AP propellant, it is because that autoignition temperature of the nitramine propellant was higher than that of HTPB/AP propellant. Standard deviation of absolute ($r_{wc}$/$r_{we}$)/$r_{we}$ calculated by using new empiracal equation composed of four dimensionless groups, is 6.11% less than that calculated by using original empirical equation composed of three dimensionless group. The new empiracal equation is derived from Buckingham pi theorem using the parameters such as thermal diffusivity, melting temperature. wire diameter, propellant sample diameter, frame temperature, autoignition temperature and matrix burning rate which influence on $r_w$.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.69-71
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• 2022

The 4th industrial revolution is regarded as a paradigm that determines future national competitiveness through the convergence and intelligence of various ICT technologies. In order to ensure the realization of the Korean military's national tasks and the successful implementation of Defense Reform 2.0, the vision for the promotion of the 'Defense Innovation Plan in the Era of the 4th Industrial Revolution' was set as 'implementation of smart defense innovation based on the 4th industrial revolution'. However, it is time to review whether the data value chain, which is the core of the 4th industrial revolution, is considered before full-scale business promotion according to the vision. In this paper, we compared and analyzed the smart defense innovation promotion project and the military and pan-government data platform project in terms of the data value chain, and suggested policy alternatives to build a defense data ecosystem.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.05a
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• pp.383-386
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• 2006

Several HTPB/AP and HTPB/AP/HMX propellants were investigated experimentally for ignition characteristics in subatmospheric pressure. The threshold ignition pressure was 4psia for HTPB/AP composite propellant. The partial replacement of AP in HTPB/AP composite propellant by $5\sim15%$ of HMX, HNIW showed improvements in the threshold pressure was below 0.4psia. This appears to be due to the exothermic dissociation characteristics of HMX and HNIW at lower temperature $(\sim220^{\circ}C)$ than that of AP. The ignition substance B/KNO3 was coated thinly on the propellant surface for better ignition effect. As a result, ignition delay time of 15% was improved. NC is applied to $B/KNO_3$ ignition substance as a secondary binder and $NC-B/KNO-3$ suspension solution is coated to the propellant surface.

• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.3
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• pp.67-72
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• 2006

Several propellants were investigated experimentally for ignition characteristics in subatmospheric pressure. The threshold ignition pressure was 4 psia for HTPB/AP composite propellant. The partial replacement of AP in HTPB/AP propellant by $5{\sim}l5%$ of HMX, HNIW showed that the improvements in ignition delay was over 50% and the threshold pressure was below 0.4 psia. This appears to be due to the characteristics of HMX and HNIW exothermic dissociated at the temperature(${\sim}220^{\circ}C$) love. than that of AP. The ignition substance $B/KNO_3$ was coated thinly on the propellant surface for better ignition performance. As a result, ignition delay time of 15% was improved. NC is applied to $B/KNO_3$ ignition substance as a secondary binder and $NC-B/KNO_3$ suspension solution is coated to the propellant surface.

• 에너지협의회보
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• s.76
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• pp.38-43
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• 2006

2007년이면 온실가스 배출통계 시스템 구축이 완료된다. 산자부는 에너지∙산업공정부문 배출통계 작성, 관리에 관한 법적근거를 에너지기본법에 신설하고, 『온실가스통계 DB구축 추진협의회』를 구성, 온실가스 인벤토리시스템(KONIS：Korean National Inventry System)을 구축한다. 또한 산업, 가정∙상업, 수송부문 최종소비단계의 온실가스 배출량 조사를 추진하여 국가에너지종합정보DB를 구축한다. 산자부는 온실가스통계 체계 구축을 통해 기술적, 경제적 감축잠재량을 분석하고, 정부-산업계가 수용 가능한 수준의 자발적 감축규모를 산정할 계획이다. 이를 통해 Post-2012 국제협상에 대비한 우리나라 대응전략을 수립하고, 산업계의 기후변화협약 대응능력과 조기감축 노력을 촉진할 수 있을 것으로 기대한다.