http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Robust Adaptive Control of A HexaSlide Type Parallel Manipulator
Kim, Jong-Phil,Kim, Sung-Gaun,Ryu, Jeha Institute of Control 2001 Transaction on control, automation and systems eng Vol.3 No.4
Jeha Ryu Department of Mechatronics, Kwangju Institute of Science and Technology This paper presents an application of a robust adaptive control strategy to HexaSlide type six degrees-of-freedom parallel manipulators. The HexaSlide type parallel manipulators are characterized as an architecture with constant link lengths that are attached to moving sliders on the ground and to a mobile platform. The proposed control law is developed based on a simplified second order system dynamic equation in joint space with uncertain mass, damper, spring, and Coulomb friction terms. These uncertain parameters are updated by an adaptation law that is derived by Lyapunov stability theorem. A robust adaptive control law by using the boundary layer is designed for the purpose of compensating for the neglected dynamic effects of the mobile platform and the six moving links that are modeled as a disturbance term. Experimental results show good and fast tracking performance.
Jeha Kim 한국진공학회(ASCT) 2019 Applied Science and Convergence Technology Vol.28 No.6
We investigate the effect of hydrazine on the growth and physical characteristics of ZnS thin films deposited on both soda–lime glass (SLG) and copper indium gallium selenide (CIGS)/Mo/SLG substrates as a function of the relative molar ratio of hydrazine to ammonia reagent, rc, for various deposition times td. As rc is varied from 0 to 0.56, all the ZnS films on SLG (thickness of d ~ 38 nm) with hydrazine exhibit an amorphous structure, [S/Zn] composition of ~ 0.65, and direct energy bandgap of Eg = 3.54 – 3.75 eV. To compare the difference in device quality corresponding to the two types of substrates, we fabricate CIGS solar cells using ZnS buffers grown under conditions of rc = 0.28, 0.42 for td = 30 min, 15 min and without hydrazine with rc = 0.0 and td = 90 min. The sample obtained with the ZnS buffer under conditions of rc = 0.28, td = 30 min exhibits the best solar cell performance of η = 12.03 %. Our results prove that using hydrazine for ZnS buffer layer preparation via chemical bath deposition can significantly enhance the film quality for CIGS solar-cell fabrication.
SpiderBot™ : A New Silver Robot Platform for the Elderly and the Handicapped
Jeha Ryu,Hossein S.Farahani,Bohyun Kim,Sung-Gaun Kim,Nam-Gyun Kim 한국과학기술원 인간친화 복지 로봇 시스템 연구센터 2004 International Journal of Assistive Robotics and Me Vol.5 No.3
This paper presents a new silver robot platform, SpiderBot™. The assistance scenario and conceptual design of the Spider Bot™ for better performance compared to the conventional mobile silver robots are discussed. The conceptual design is addressed considering real residence environment, human friendliness, and user convenience. The design is divided into mechanical parts, control parts, driving parts, sensor parts, and end-effectors. Loading condition and loading scenario for various assistance modes are briefly investigated to meet various requirements for the elderly and the handicapped. The dynamic model of the robot, adaptive control was simulated to verify the feasibility of the SpiderBot™ platform.
Sehun Kim,Jong-Phil Kim,Ryu, Jeha IEEE 2014 IEEE/ASME transactions on mechatronics Vol.19 No.4
<P>Even though impedance control approaches are useful for robot interaction control, they can guarantee stability only for the assumed range of the environments. This paper presents a new adaptive energy-bounding approach (EBA) that can maintain a desired contact force at steady state while guaranteeing robust contact stability for impedance-controlled industrial robots that are contacting with very uncertain environments beyond the assumed range of the environments. The proposed adaptive EBA that is applied to impedance-controlled industrial robots interacting with incompletely specified real environments is an extension of the haptic EBA, which was previously developed for stable haptic interaction with virtual environments. Moreover, the adaptive EBA estimates online control parameters to improve performance while assuring stability for the system. Theoretical analyses on the performance and experimental results demonstrate the effectiveness of the proposed approach.</P>
류제하(Jeha Ryu),김재하(Jaeha Kim),서창훈(Changhoon Seo),임요안(Yo-An Lim),김종필(Jong-Phil Kim) 대한기계학회 2009 大韓機械學會論文集A Vol.33 No.4
Haptics technology allows one to interact with virtual environments, augmented environments, and real environments providing tactual sensory information. Science and technology of haptics can in general be classified into three groups: machine haptics, computer haptics, and human haptics. This paper surveys the state-of-the-art of haptic control technology for virtual environments and teleoperation (real environments) and then proposes possible future research directions in the following areas: haptic stability control, bilateral teleoperation control, and stability enhancement control.
불확실 환경에서 산업용 로봇의 안정적 상호작용을 위한 어드미턴스 에너지 제한 알고리즘의 적용
류제하(Jeha Ryu),김세훈(Sehun Kim),김종필(Jongphil Kim) 대한기계학회 2011 대한기계학회 춘추학술대회 Vol.2011 No.5
Stability is an important for robot interaction control with environment. Even though robust impedance controls are useful for robot interaction control, they can only guarantee stability for a designed range of environment. This paper presents an admittance type energy bounding approach (AEBA) to achieve robust stability for uncertain environments. The proposed controller is a combination of the EBA with conventional robust impedance controller. We also demonstrate the design of parameters of AEBA to guarantee contact stability under unstable areas and preserve impedance control’s response under stable areas and show experimental results.
( Taewoo Kim ),( Jeha Jeon ),( Jin-sun Park ),( Yeongwon Park ),( Jooeui Kim ),( Haneul Noh ),( Hee-sun Kim ),( Hyemyung Seo ) 한국응용약물학회 2021 Biomolecules & Therapeutics(구 응용약물학회지) Vol.29 No.5
Parkinson’s disease (PD) is a neurodegenerative disorder that involves the loss of dopaminergic neurons in the substantia nigra (SN). Matrix metalloproteinases-8 (MMP-8), neutrophil collagenase, is a functional player in the progressive pathology of various inflammatory disorders. In this study, we administered an MMP-8 inhibitor (MMP-8i) in Leucine-rich repeat kinase 2 (LRRK2) G2019S transgenic mice, to determine the effects of MMP-8i on PD pathology. We observed a significant increase of ionized calcium- binding adapter molecule 1 (Iba1)-positive activated microglia in the striatum of LRRK2 G2019S mice compared to normal control mice, indicating enhanced neuro-inflammatory responses. The increased number of Iba1-positive activated microglia in LRRK2 G2019S PD mice was down-regulated by systemic administration of MMP-8i. Interestingly, this LRRK2 G2019S PD mice showed significantly reduced size of cell body area of tyrosine hydroxylase (TH) positive neurons in SN region and MMP-8i significantly recovered cellular atrophy shown in PD model indicating distinct neuro-protective effects of MMP-8i. Furthermore, MMP-8i administration markedly improved behavioral abnormalities of motor balancing coordination in rota-rod test in LRRK2 G2019S mice. These data suggest that MMP-8i attenuates the pathological symptoms of PD through anti-inflammatory processes.
무선 원격 통신 기술을 활용한 언택트 모바일 버스 정차 예약 서비스
김재하(JEHA KIM),고석찬(SEOKCHAN GO),이계민(GYEMIN LEE) 한국방송·미디어공학회 2020 한국방송공학회 학술발표대회 논문집 Vol.2020 No.11
본 작품은 코로나 바이러스로 인한 언택트 서비스의 부각과 더불어, 대중교통 이용시 승객들이 하차에 신경쓰지 않고 자신의 일에 집중 할 수 있도록 지원하기 위해 제작된 서비스이다. 버스 하차 전(혹은 승차 시) 미리 희망하는 하차 지점을 예약해놓으면 해당 정류장에 자동으로 버스의 하차벨을 울리게 된다. 스마트폰 앱과 버스에 설치된 단말을 활용하여 추가적인 설치비용을 절약하며, 이 후 완성된 시스템을 발전시켜 사용자별 타겟광고가 가능해지면 버스회사의 부족한 재원을 보다 확보할 수도 있다.