http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
박봉균,조규형,이태구,이익수,김진숙,김찬식 한국운동영양학회 2019 Physical Activity and Nutrition (Phys Act Nutr) Vol.23 No.4
[Purpose] Here, we aimed to determine the effect of Polygonum cuspidatum stem extract (PSE) on exorbital lacrimal gland-excised rat models and hyperosmotic stress-stimulated human conjunctival cells (HCCs). [Methods] Seven week old male Wistar rats were divided into six groups. Only the rats in the control group (NOR, n=5) did not undergo surgery. Three days after the surgery, the exorbital lacrimal gland-excised rats were randomly allocated to five groups: (1) vehicle-treated dry-eyed rats (DED, n=5); (2) PSE (10mg/kg) treated DED rats (PSE-10, n=5); (3) PSE (100mg/kg) treated DED rats (PSE-100, n=5); and (4) PSE (250mg/kg) treated DED rats (PSE-250, n=5). In addition, the HCC line was co-treated with hyperosmolar media (528 mOsm) and PSE (1-100μg/ml). [Results] PSE treatment restored the tear volume and goblet cell density by inhibiting severe corneal irregularities and damage. The treatment with PSE significantly attenuated the hyperosmolar stress-induced inflammation and cell death through the suppression of mRNA expression levels of Tumor necrosis factor-α (TNF-α), Interleukin-6 (IL-6), Interleukin-1β (IL-1β), and Interferon-γ (IFN-γ), and the expression of Bcl-2-associated X protein (Bax) as well as the activation of caspase-3 in vitro. [Conclusion] The inhibitory effects of PSE treatment on dry eye disease indicate the potential of nutritional intervention by PES against inflammatory diseases without adverse effects.
Time-Delay Control for Integrated Missile Guidance and Control
박봉균,김태훈,탁민제 한국항공우주학회 2011 International Journal of Aeronautical and Space Sc Vol.12 No.3
In this paper, integrated missile guidance and control systems using time-delay control (TDC) are developed. The next generation missile requires that an interceptor hits the target, maneuvering with small miss-distances, and has lower weight to reduce costs. This is possible if the synergism existing between the guidance and control subsystems is exploited by the integrated controller. The TDC law is a robust control technique for nonlinear systems, and it has a very simple structure. The feature of TDC is to directly estimate the unknown dynamics and the unexpected disturbance using one-step time-delay. To investigate the performance of the integrated controller, numerical simulations are performed as the maneuver of the target. The results show that the integrated guidance and control system has a good performance.
박봉균,권혁훈,김윤환 한국항공우주학회 2015 한국항공우주학회 학술발표회 논문집 Vol.2015 No.11
본 논문에서는 정지된 표적에 대하여 유도탄의 충돌각 제어를 위한 탐색기의 지향각 성형 기법에 대해서 기술한다. 표적 타격 시 충돌각을 고려하게 되면, 유도탄의 궤적이 크게 성형되기 때문에 탐색기의 field-of-view(FOV)내에서 표적을 놓칠 수가 있다. 따라서 제한된 FOV 를 가지는 유도탄의 충돌각 제어를 위해서는 탐색기의 지향각 제한을 고려한 운용이 반드시 필요하게 된다. 일반적으로 사용되는 가속도 제어를 할 경우 유도탄의 빠른 기동을 할 수 있는 장점이 있지만, 탐색기의 지향각을 직접 제어할 수 없는 단점이 있다. 본 논문에서 제안하는 지향각 성형 기법은 가속도 제어 대신 탐색기에서 생성되는 지향각을 원하는 값으로 직접 제어하여 탐색기의 FOV 내에서 충돌각 제어가 가능하도록 한다. 다양한 교전조건에 대한 비선형 시뮬레이션을 통해서 제안된 지향각 성형 기법의 성능 분석을 수행한다. In this paper, a seeker’s look angle shaping method is described for impact angle control against a stationary target. The seeker can miss the target within the field-of-view(FOV) because missile trajectories are highly curved when implementing the impact angle control. Therefore, it is very important to consider the seeker’s FOV limit when operating a missile with the seeker. In case of acceleration control generally used in a missile system, the missile has an advantage of a fast response, but it cannot directly control the seeker’s look angle. The proposed shaping method, which can directly handle the look angle, is possible to achieve the desired impact angle without violating the FOV limits. The performance of the proposed shaping method is investigated through nonlinear simulations for various engagement conditions.
박봉균,Park, Bong-Gyun 환경보전협회 2015 환경정보 Vol.419 No.-
화관법의 전면 개정으로 화학사고 예방 대비 대응을 위한 제도적 정비는 일단락되었으나 제도의 집행과 실천이 중요하다. 이에 정부는 제도의 집행역량을 강화하기 위해 전문성을 확보하고 현장적용성을 꼼꼼하게 검토할 것이며, 중소기업에 대한 안전진단 컨설팅 등 정부가 할 수 있는 지원을 지속할 것이며, 현장의 애로사항도 계속 발굴하여 제도가 안착될 수 있도록 노력할 것이다. 사업장도 스스로 안전관리를 강화하고 안전의식을 높이기 위해 노력해주기를 바란다.
Two-Dimensional Trajectory Optimization for Soft Lunar Landing Considering a Landing Site
박봉균,안종선,탁민제 한국항공우주학회 2011 International Journal of Aeronautical and Space Sc Vol.12 No.3
This paper addresses minimum-fuel, two-dimensional trajectory optimization for a soft lunar landing from a parking orbit to a desired landing site. The landing site is usually not considered when performing trajectory optimization so that the landing problem can be handled. However, for precise trajectories for landing at a desired site to be designed, the landing site has to be considered as the terminal constraint. To convert the trajectory optimization problem into a parameter optimization problem,a pseudospectral method was used, and C code for feasible sequential quadratic programming was used as a numerical solver. To check the reliability of the results obtained, a feasibility check was performed.