http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
펄스폭 변조기 기반 추력 제어기를 이용한 달 착륙선 지상시험모델의 경로 추종 성능 연구
양성욱,손종준,이상철,Yang, Sung-Wook,Son, Jong-Jun,Lee, Sang-Chul 한국항공운항학회 2014 한국항공운항학회지 Vol.22 No.4
A lunar lander demonstrator developed for the purpose of demonstrating lunar landing technologies recently in Korea. The thruster control system of the lunar lander demonstrator adopted the main thrusters for altitude control and the reaction thrusters for attitude control. In this paper, we propose a path tracking controller base on Euler angles. The control signals of the controller are of continuous type. And Pulse Width Modulator(PWM) is adopted to provide On/Off signals. We perform MATLAB simulation for evaluating the path tracking performance and the final landing velocity of the lunar lander demonstrator.
수치해 검증방법을 이용한 기호 연산 프로그램 성능 비교
양성욱,이상철,Yang, Sung-Wook,Lee, Sang-Chul 한국항공운항학회 2015 한국항공운항학회지 Vol.23 No.2
We propose a rigorous and practical methodology to evaluate the performance of symbolic manipulation program such as Mathematica, Maple, and Maxima. First, we demonstrate an inverse method to construct the benchmark problems of an initial value problems. The benchmark problems associated with the discrete version of the Chebyshev polynomials provide a rigorous and objective measure to evaluate the performance of symbolic manipulation programs. We compare three symbolic manipulation programs, which are Mathematica, Maple and Maxima, using this methodology. The computation time, the used memory and the perturbation terms are chosen for comparison parameters.
양성욱,양준모,이상철,Yang, Sung-Wook,Yang, Jun-Mo,Lee, Sang-Chul 한국항공운항학회 2014 한국항공운항학회지 Vol.22 No.4
In the development of an avionics system, there is a trend of using commercial-off-the-shelf(COTS) equipments in order to reduce the development cost and time. In this paper, we present an implementation of an aircraft mission computer using the objected oriented software and the COTS equipments. We execute the aircraft guidance software on the system, and measure the calculation time and the used memory. To compare the guidance capability of the software program, we implement the same software logic on DS1104 system. The guidance software program executed on two different systems resulted in the almost identical simulation.
달 착륙선의 동역학 모델링 및 추력기 기반 제어기 설계
양성욱,이상철,Yang, Sung-Wook,Lee, Sang-Chul 한국항공운항학회 2015 한국항공운항학회지 Vol.23 No.1
This paper deals with dynamic modeling and controller design of a future Korean lunar module planned to be launched 2020's in Korea. For dynamic modeling of the lunar module, we first assume the lunar module as a rigid body. And we derive equations of motion for the lunar module by considering allocation of main thrusters and reaction thrusters. With the equation of motion, we design the controller based on the quaternion. A Pulse Width Pulse Frequency modulator(PWPFM) is selected for generating on/off signal. Finally, we construct a 2-phase descent mode including initial guidance mode, terminal guidance mode. The MATLAB simulation is performed for evaluating the descent ability and final landing velocity. The dynamic modeling and descent simulation of the lunar module in this paper could be applied for developing the future work of the Korean lunar exploration program.
증예(症例) : 반복된 뇌경색으로 발현된 폐동정맥 기형과 폐동맥 색전술을 이용한 치료 1례
양성욱 ( Sung Wook Yang ),조준성 ( Jun Sung Jo ),유지원 ( Ji Won You ),박상민 ( Sang Min Park ) 전북대학교 의과학연구소 2009 全北醫大論文集 Vol.33 No.2
Pulmonary arteriovenous malformation(PAVM) is a rare pulmonary vascular anomaly due to an abnormal communication between the pulmonary artery and vein. PVAM also rare cause of stroke via paradoxical embolism. The most common presenting sysptom is a dyspnea on exertion related to this right to left shunt. 58-year-old woman with past three times cerebral infarct was complaint about right chest pain and continuous headache. PVAM was detected on chest X-ray and dynamic CT,which were embolized with coil successfully. We suggest that PVAM might be one of the rare causes of stroke especially in young adult.
객체지향 기반 실시간 지리정보 전문가시스템의 설계를 위한 접근
양성욱(Sung Wook Yang),이태경(Tae Kyung Lee) 한국정보과학회 1997 한국정보과학회 학술발표논문집 Vol.24 No.2Ⅱ
실시간 지리정보 전문가시스템은 지리정보 시스템에 실시간 의사결정을 추가한 형태로서 가스관 관리시스템과 같은 공간정보와 관련된 실시간 업무처리 분야에 적요된다. 실시간 지리정보 전문가시스템은 지리정보시스템, 전문가시스템, 실시간시스템의 특성을 모두 지녀야 하는 복잡한 시스템이다. 본 논문에서는 객체지향 이론을 적용하여 실시간 지리정보 시스템의 복잡성을 줄이고, 최대한 지리정보의 특성을 반영하는 설계를 위한 접근방법을 제안하였다. 실시간 지리정보 전문가 시스템을 지리정보 객체와 모니터링 객체의 두 객체로 설계하였으며, 작업흐름은 메시지에 의한 지리정보 객체의 상태전이로 표현하였고, 지리정보 객체를 가장 기본적인 프로그램을 단위로 인식하여 지식베이스와 추론기능을 모두 지니게 하였다. 그리고, 객체지향 이론을 적용하여 지리정보의 계층구조, 지식베이스의 계층구조, 복합객체를 표현하였다. 실시간 추론시에 추론결과의 정확성을 보장하고 시간제약을 지키기 위해서 모니터링 객체를 사용하였다.
양성욱 ( Sung Wook Yang ),이상철 ( Sang Chul Lee ) 한국항공운항학회 2008 한국항공운항학회지 Vol.16 No.2
An inverse method is introduced to construct the problem for the error analysis of the numerical solution of initial value problem. These problems constructed through this method have a known exact solution, even though analytical solutions are generally not obtainable. The process leading to the exact solution makes use of an initially available approximate numerical solution. A smooth interpolation of the approximate solution is forced to exactly satisfy the differential equation by analytically deriving a small forcing function to absorb all of the errors in the interpolated approximate solution. Using this special case exact solution, it is possible to investigate the relationship between global errors of a candidate numerical solution process and the associated tuning parameters for a given problem. Under the assumption that the original differential equation is well-posed with respect to the small perturbations, we thereby obtain valuable information about the optimal choice of the tuning parameters and the achievable accuracy of the numerical solution.