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.

사진 주사(走査)를 이용한 치과용 모형재의 정확도에 관한 연구

양성욱,임주환,조인호,Yang, Seong-Wook,Lim, Ju-Hwan,Cho, In-Ho 대한치과보철학회 1996 대한치과보철학회지 Vol.34 No.2

Dental cast and die materials are essential material using in almost dental prsthodontic procedure and it's most important requirement is accuracy for reqorducing the oral anatomical structures. In this study, 5 abutments A, B, C, D, E were fabricated on the metal master model to simulate the arch form and specimens were poured with 4 cast materials. Inter-abutment distances, A-B, A-C, A-D, A-E, B-C, B-D were calculated using the photo-scanning and the deviations from the metal master model were also evaluated. The results were as follows; 1. The distance between A-B, A-C, A-D, A-E, B-C, B-D of the abutments A, B, C, D, E of each cast material was calculated. And after comparing the deviations between the metal master model. $Fujirock^{(R)}$ showed the lowest value with $0.20{\pm}0.22mm$, and the deviation increased in the order of $Suprastone^{(R)}$, Epoxy $Die^{(R)}$, Die $Keen^{(R)}$. There was significant difference between $Fujirock^{(R)}$ and Epoxy $Die^{(R)}$, Die $Keen^{(R)}$. 2. In each calculation area, the difference in measurements between cast material and metal master model showed singificant difference between A-B and Cross arch measure-ments of A-D, B-D, A-E(p<0.05). 3. The difference in measurements between cast material and metal master model in the A-B area showed $Fujirock^{(R)}$ to be the lowest with $0.05{\pm}0.04$mm and increased in the order of Die $Keen^{(R)}$, $Suprastone^{(R)}$, Epoxy $Dies^{(R)}$. There was significant difference between $Fujirock^{(R)}$ and $Suprastone^{(R)}$, Epoxy $Die^{(R)}$ (p<0.05). 4. The difference in measurements between cast material and metal master model in the B-C area showed $Fujirock^{(R)}$ to bo the lowest with $0.17{\pm}0.11$mm and increased in the order of $Suprastone^{(R)}$, Die $Keen^{(R)}$, Epoxy $Dies^{(R)}$. There was significant difference between $Fujirock^{(R)}$ and Die $Keen^{(R)}$, Epoxy $Die^{(R)}$(p<0.05). 5. The difference in measurements between cast material and metal master model in the B-D area showed $Fujirock^{(R)}$ to bo the lowest with $0.13{\pm}0.07$mm, Epoxy $Dies^{(R)}$and increased in the order of $Suprastone^{(R)}$, Die $Keen^{(R)}$. There was significant difference between $Fuji-rock^{(R)}$ and Die Keen(p<0.05). 6. In this experiment, Epoxy $Dies^{(R)}$ showed mean contraction in every calculation area. And when reconstruction cross arch restorations it is thought that distortion should be considered in every cast material.

상용 기성품 기반 항공기 임무컴퓨터 구현에 관한 연구

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.

항공전사 시스템 소프트웨어의 개발 추세에 대한 연구

양성욱,이상철,Yang, Sungwook,Lee, Sangchul 항공우주시스템공학회 2007 항공우주시스템공학회지 Vol.1 No.1

The importance of software development in the integration of an avionics system is continuously increasing. And we can expect enlarged soft ware portion in the system integration for the more intelligent, reliable, and automated avionics system. For an avionics system software development the selection of a real-time operating system and internal avionics data bus protocol is very important from the viewpoint of the integration with the system hardware. In this paper, we present current trend of an avionics system software development including software development methodology, software development process, and international software process assessment improvement model.

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.

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.

처리 방법이 다른 표면이 임플랜트의 골유착 및 안정성에 미치는 영향

양성욱,임헌송,조인호,Yang, Seoung-Wook,Lim, Heon-Song,Cho, In-Ho 대한치과보철학회 2006 대한치과보철학회지 Vol.44 No.5

Purpose: This experiment examined the effect of different surface treatment on the osseointegration and stability of implants. Material and methods: In this study, 40 each of machined, SLA and RBM implants, which are the most commonly used implants, were implanted into the tibia of 20 normal rabbits using $OsseoCare^{TM}$. The rabbits were sacrificed after 1 week, 4 weeks, 8 weeks and 12 weeks for implant stability analysis, removal torque analysis, histologic and histomorphometric analysis. Result : ISQ showed significant difference between Machined and RBM at first week and at 4 weeks. There was significant difference between Machined and both SLA and RBM(p<0.05) but after 8 weeks there were no significant difference between each group. In the removal torque, RBM showd significantly higher values than SLA and Machined surface at 1st week. At 4th and 12th week, there was significant difference between Machined and SLA, RBM(p<0.05). In the bone to implant contact variable, there was no significant difference between each surface treatment method. In the Machined surface group, there was no significant difference between each time interval. but in SLA group, there were significant differences between the 1st week and 12th week and in RBM group, there were significant differences between the 1st week and 8th, 12th week and between 4th and 12th week(p<0.05). The bone area showed significantly higher values in SLA and RBM compared to Machined surface 1st and 8th week and significantly higher values in SLA than Machined surface at the 4th week(p<0.05). Conclusion: The roughened surface of implants showed positive effect in the early stages of implantation and assisted in bone formation After the bone formation stage, there was no statistical difference between Machined and roughened surface groups. In dental implantation, where initial stability is critical to the success of implants, the use of roughened surface implants should assist in reducing the healing period after implantation.

추적 레이다용 Dual-band 모노펄스 수신기

양성욱,박동민,나영진,Yang Seong-Uk,Park Dong-Min,Na Young-Jin 한국전자파학회 2006 한국전자파학회논문지 Vol.17 No.8

레이다 기술의 국산화가 이슈가 되고 연구 개발에 박차를 가하고 있는 가운데 본 논문의 Dual-band 모노 펄스 수신기는 추적 레이다를 기반으로 한 실험적 수행 결과를 바탕으로 하고 있다. Dual-band 레이다를 Single-band 레이다와 비교해 보면 높은 비용과 소비 전력 등의 단점을 갖고 있지만 재밍이나 검파 거리, 이미지 신호 제거, 강우 감쇄 특성 면에서 이점을 가질 수 있다. 수신기는 X-band RF head 모듈, Ka-band RF head 모듈, 그리고 공통 IF모듈로 구성되며 X-band와 Ka-band의 각 신호는 IF 모듈의 스위칭에 의해 선택되어진다. 또한 IF모듈의 국부 신호단에서는 위상 제어기가 장착되어 합 채널을 기준으로 고각과 방위각 채널의 위상을 제어할 수 있도록 하였다. 측정 결과 전체 이득은 $40{\pm}3 dB$였으며, 송신/수신간 격리도는 39 dBc, 동적 영역 110 dB, 그리고 잡음지수는 X/Ka-band 각각 4.5dB/6.9dB로 나타났다. The receiver of this paper is Dual-band monopulse type for prototype of tracking radar. Localization of radar technology is an issue of SamsungThales and go into development. Dual-band radar in comparison with Single-band radar requires higher cost and power consumption but there are many advantages of dealing with jamming, detection range, image signal rejection, cloud-rain influence, clutter, resolution. The receiver is comprised of X-band RF head module, Ka-band RF head module and common IF module. Each signal of X-band and Ka-band is selected by the switch in If module. Phase shifter in IF module of local stage controls the phase of sum, azimuth, elevation channel. In the test result, gain is $40{\pm}3 dB$, isolation of transmitter/receiver is 39 dBc, dynamic range is 110 dB and noise figure of each channel is 4.5dB and 6.9dB.

마을공동체 지원사업과 사회복지관 지역조직화의 관계에 대한 질적연구

양성욱(Yang, Seong wook),서종건(Seo, Jong Gun) 경북대학교 사회과학연구원 2021 사회과학 담론과 정책 Vol.14 No.2

본 연구는 ‘마을공동체 지원사업의 확대가 사회복지관의 주민조직화에 어떠한 영향을 미쳤는가?’라는 질문을 중심으로 선행연구의 주장과 같이 마을공동체 형성이 사회복지관 지역조직화의 중심인지, 마을공동체 지원사업의 확대는 어떻게 인식되고, 그들의 활동에 어떠한 영향을 미치고 있는지를 분석하고자 하였다. 이를 위해 자치구 및 시 단위 조례가 비교적 최근에 재·개정된 D시의 6개 복지관의 관리자를 대상으로 심층면접을 수행하였다. 연구 결과, 사회복지관의 지역조직화는 기관 중심에서 주민욕구 중심으로, 자원개발과 네트워크 중심에서 주민조직화 중심으로 변화하고 있었다. 이와는 반대로 마을공동체 형성과 관련된 영역에 대한 혼란과 사회복지관의 중심적 역할에 대한 내부 갈등도 존재하였다. 또한, 마을공동체 지원사업에서 사회복지관은 구조적으로 배제되고 있었고, 이에 대한 참여는 비공식적으로 이루어졌다. 그 결과 마을공동체 지원사업은 사회복지관 내에서 주민조직화와 분리되고 예산 확보를 위한 수단으로 인식되었으며, 기관이 주도하는 사업이 되기도 하였다. This study is interested in how community building ordinance project has effects on the community organization of social welfare centers. As argued in previous studies, we tried to analyze whether the formation of community building is the center of community organization in social welfare centers, how the expansion of community building support projects is perceived, and how they affect their activities. To find the phenomenon, 6 interview data were analyzed in 6 agencies’ managers in city of D where the community building ordinance was enacted recently. The main results are as follows : Fritst, the community organization of social welfare centers was changing from organization to local resident needs, and from resource development and network to community building. On the contrary, there was confusion over areas related to community building and internal conflict over the central role of social welfare centers. Second, social welfare centers were structurally excluded from the community building support project, and their participation was informal. As a result, community building support project was recognized as a means to secure a budget and was separated from the community building within the social welfare center, and it became a project led by them.

망막모세포종 세포주에서 Buthionine Sulfoximine 에 의한 항암제의 세포독성 증강

양성욱(S W Yang),최광주(G J Choi),지남철(N C Ji) 대한안과학회 1996 대한안과학회지 Vol.37 No.1