달 탐사선 시뮬레이터 개념설계 연구

류동영,주광혁,이상률 한국항공우주학회 2010 한국항공우주학회 학술발표회 논문집 Vol.2010 No.11

가상비행시험을 이용한 달 착륙선 지상시험모델의 제어기 설계 검증

류동영,구철회,권재욱,이훈희,이원범,주광혁 한국항공우주학회 2013 한국항공우주학회 학술발표회 논문집 Vol.2013 No.4

달 착륙선 지상시험모델을 이용한 가상비행시험 연구

류동영,이원범,권재욱,주광혁,심은섭 한국항공우주학회 2012 한국항공우주학회 학술발표회 논문집 Vol.2012 No.11

달 착륙선 지상시험모델의 지상시험의 목적은 비행모델 탐사선의 개발 이전에 주요 전자장비, 추진시스템, 제어 알고리즘 및 소프트웨어, 구조체의 핵심기술 및 체계운용기술 등의 전체 시스템에 대한 시연 및 검증이다. 계획된 지상시험은 추력기 클러스터링 시험과 가상비행시험으로 구성된다. 추력기 클러스터링 시험은 이착륙제어용 추력기의 클러스터 기술을 검증하기 위한 것이고, 가상비행시험은 추력기 클러스터링 시험과 이착륙 및 자세제어 추력기와 실시간 시뮬레이터를 이용하여 자유비행시험을 제외한 비행 시나리오에 따라 제어 및 운영 시스템과 착륙기술을 시험하기 위한 것이다. 향후에는 자유비행시험을 수행하여 추가적인 개선을 통하여 위험물 감지 및 회피 기술 시험 등에 활용할 예정이다. 본 논문에서는 달 착륙선 지상시험모델의 지면고정상태에서의 가상비행시험 방안에 대해 기술한다. The purposes of ground test of lunar lander demonstrator are to demonstrate and verify essential electronics, propulsion system, control algorithm, embedded software, structure and system operation technologies before developing the flight model lander. The planned ground test consists of thruster clustering test and virtual flight test. The thruster clustering test is to validate the clustering technology of five 200 newton thrusters. Although we do not perform actual free flight test in this research stage because of the safety issue, we test the control and operation system and landing technology by virtual flight test in which thrusters are actually fired by command of the control system according to the pre-defined flight scenario and simulated flight dynamics of the vehicle. In the future, as the free flight will be done, the Autonomous Landing and Hazard Avoidance Technology (ALHAT) are utilized through additional upgrade. This paper describes the plans about virtual flight test with lunar lander demonstrator being fixed on the ground.

Conceptual Design of Korea Aerospace Research Institute Lunar Explorer Dynamic Simulator

류동영,주광혁,강상욱,이상률 한국우주과학회 2010 Journal of Astronomy and Space Sciences Vol.27 No.4

In lunar explorer development program, computer simulator is necessary to provide virtual environments that vehicle confronts in lunar transfer, orbit, and landing missions, and to analyze dynamic behavior of the spacecraft under these environments. Objective of simulation differs depending on its application in spacecraft development cycle. Scope of use cases considered in this paper includes simulation of software based, processor and/or hardware in the loop, and support of ground-based flight test of developed vehicle. These use cases represent early phase in development cycle but reusability of modeling results in the next design phase is considered in defining requirements. A simulator architecture in which simulator platform is located in the middle and modules for modeling, analyzing, and three dimensional visualizing are connected to that platform is suggested. Baseline concepts and requirements for simulator development are described. Result of trade study for selecting simulation platform and approaches of defining other simulator components are summarized. Finally, characters of lunar elevation map data which is necessary for lunar terrain generation is described.

상황버섯 추출물의 항산화 효과

류동영,김민석,민오진,김동욱 한국자원식물학회 2008 한국자원식물학회지 Vol.21 No.1

Reactive oxygen species (ROS) or free radical-mediated oxidative stress plays an important role in the pathophysiologic process of disease state. This study investigated antioxidative effects of Phellinus linteus extract on the generation of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, superoxide anion radical (O2-), hydroxyl radical (·OH), nitric oxide (NO), and peroxynitrite (ONOO-) radical and free radical-mediated protein oxidation under in vitro assay systems. This results showed that Phellinus linteus extract effectively inhibited the generation of free radicals in the all assay system with dose-dependent manner and also significantly reduced the protein oxidative level. Thus, the present study indicates that Phellinus linteus extract possesses a potent antioxidant activity and plays a beneficial role against free radical-induced oxidative injury.

3T3-L1 지방세포와 db/db 마우스에서 옥수수수염 물 추출물의 지방생성 억제 및 혈당 저하효과

류동영,민오진,샤르마베스라지,박철민 한국생약학회 2011 생약학회지 Vol.42 No.2

Obesity occur from the imbalance between energy intake and energy expenditure. Obesity is a complex chronic disease that is suggested to cause other metabolic disorders such as type 2 diabetes, hyperlipidemia, hypertension, and arteriosclerosis. In this study, our purpose is to investigate the anti-hyperglycemic and anti-obesitic effects of Maydis stigma water extract in 3T3-L1 adipocytes and db/db mice. Maydis stigma water extract at dose of 100 and 500 μg/ml slowly inhibited cell viability as compared to that of control in mature adipocytes. Also, the additions of 50 and 250 μg/ml of Maydis stigma water extract significantly inhibited the lipid accumulations and CCAAT/enhancer-binding protein(C/EBP) α and peroxisome proliferator-activated receptor(PPAR) γ expressions with dose-dependent manner in 3T3-L1 adipocytes. Maydis stigma water extract at 250, 500, and 1000 μg/ml only showed the increasing pattern on lipolysis activity. The oral treatment of Maydis stigma water extract (100 or 400 mg/kg body weight) in db/db mice only showed tendency to decrease body weight, food efficiency ratio (FER), HbA1c, blood glucose, total cholesterol, triglyceride, and the adipocyte size of in db/db mice. However, Maydis stigma water extract increased the insulin level in a dose dependent manner. Thus these results indicate that Maydis stigma water extracxt inhibits adipogenesis through regulation of C/EBPα and PPARγ expressions in 3T3-L1 adipocytes and shows anti-hyperglycemic effect through increase of insulin secretion in db/db mice.

LQG/LTR 및 PRLQG를 이용한 시선지령유도방식 설계

류동영,선병찬,탁민제 한국항공우주학회 1991 한국항공우주학회 학술발표회 논문집 Vol.- No.-

한국의 달 탐사 계획 및 준비 현황

류동영 한국진공학회 2014 한국진공학회 학술발표회초록집 Vol.2014 No.8

위성통신 서비스를 위한 저궤도 위성군 설계

류동영,서윤경,승성표 한국항공우주학회 2000 한국항공우주학회 학술발표회 논문집 Vol.- No.-

우주 현지자원활용 글로벌 동향

류동영,Dong Young Rew 한국우주과학회 2023 우주기술과 응용 Vol.3 No.3

In contrast to the short-term nature of lunar missions in the past, lunar missions in new space era aim to extend the presence on the lunar surface and to use this capability for the Mars exploration. In order to realize extended human presence on the Moon, production and use of consumables and fuels required for the habitation and transportation using in-situ resources is an important prerequisite. The Global Exploration Roadmap presented by the International Space Exploration Coordination Group (ISECG), which reflects the space exploration plans of participating countries, shows the phases of progress from lunar surface exploration to Mars exploration and relates in-situ resource utilization (ISRU) capabilities to each phase. Based on the ISRU Gap Assessment Report from the ISECG, ISRU technology is categorized into in-situ propellant and consumable production, in-situ construction, in-space manufacturing, and related areas such as storage and utilization of products, power systems required for resource utilization. Among the lunar resources, leading countries have prioritized the utilization of ice water existing in the permanent shadow region near the lunar poles and the extraction of oxygen from the regolith, and are preparing to investigate the distribution of resources and ice water near the lunar south pole through unmanned landing missions. Resource utilization technologies such as producing hydrogen and oxygen from water by hydroelectrolysis and extracting oxygen from the lunar regolith are being developed and tested in relevant lunar surface analogue environments. It is also observed that each government emphasizes the use and development of the private sector capabilities for sustainable lunar surface exploration by purchasing lunar landing services and providing opportunities to participate in resource exploration and material extraction.