시간지연을 갖는 불안정한 플랜트에 대한 3요소 PID제어기의 설계에 관한 연구

정희범 순천대학교 공업기술연구소 1998 工業技術硏究所論文集 Vol.12 No.-

In this study, the synthesis of three-element PID controller for an open-loop unstable plant with time delay is proposed. Control problem such as stabilizing an open-loop unstable plant, servo-tracking, and disturbance rejection can be treated independently by each element of the controller. Tuning rules for each element of the controller are based on the loop gain and phase criterion of root loci, the internal model controller, and feed forward controller design method. The performance of the proposed controller was presented by computer simulations of example problems.

입력-제한 시스템을 위한 자기동조 제어 알고리즘의 개발

정회범 순천대학교 공업기술연구소 1991 工業技術硏究所論文集 Vol.5 No.-

Self-tuning control algorithm for an input-constrained systems is developed and implemented in this study. Magnitude of control input for small motors is generally restricted to low level due to actuator saturation. The bounded-gain control algorithm proposed in this study yields smoother control input within the magnitude constraints comparing with the existing Clarke's suboptimal control algorithm. In the proposed algorithm, the system output responds fast at the expense of smoothness of input variation, as the weighting factor is increased. For the DC servo motor control, the system performance of the proposed algorithm is compared with that of the existing algorithm by computer simulation and experiment. The control programs are written in 8086 & 8087 assembly languages for real-time control. The output responses of both algorithms are similar, but smoothness of input variation using the proposed algorithm is verified.

탄산가스 아크용접에서 보호가스량에 따른 용접부의 기계적 성질

정회범,김봉태 順天大學校 1998 論文集 Vol.17 No.1

The mechanical properties of a welding part have been examined by varying the shield gas flow rate from 0ℓ/min to 24ℓ/min when the CO₂ gas arc welding with solid wire is used for welding the SS41 steel. The welding parts have been investigated through X-ray film test, bending test and tensile test, which have shown following results ; 1) X-ray film tests show no pores for the shield gas flow rate from 6ℓ/min to 24ℓ/min. But some pores are existed at inner welding part for the flow rate 2ℓ/min and 4ℓ/min. When no gas is supplied, many pores are observed at the inner and the outer welding parts. 2) A bead configuration including a fusion depth and a bead's width and height is good for the shield gas flow rate more than 8ℓ/min. 3) Bending tests show that no cracks were developed for the shield gas flow rate 16ℓ/min to 24ℓ/min. But cracks are developed at the surface of a face side for the flow rate 4ℓ/min to 12ℓ/min. For the flow rate 0ℓ/min and 2ℓ/min, specimens break into pieces. 4) Tensile strength of the welding part increases as the shield gas flow rate increases. The tensile strength of the welding part is much higher than that of the base metal for the flow rate 4ℓ/min to 24ℓ/min. Considering the above results, the effective shield gas flow rate in the CO₂ gas arc welding is 16ℓ/min to 24ℓ/min.

소형 로봇의 연속경로 추종제어

정회범 順天大學校 1994 論文集 Vol.13 No.1

□Magnitude of control inputs for small motors used in robot is generally restricted to low level due to actuator saturation. This paper compares the tracking performance of the bounded-gain adaptive control algorithm with the existing PD control algorithm by computer simulation and experiment. The reference trajectories are obtained using the kinematic model of Rhino XR-2 robot. The robot controller is designed and fabricated for the implementation of the control algorithms. It is shown that the bounded- gain adaptive control algorithm yields better tracking performance and smoother input variation than the PD control algorithm in the two-axis robot control.

축압축을 받는 CFRP 적층부재의 에너지흡수특성과 파괴모드에 관한 연구

김정호,정회범,전형주 한국산업안전학회 2002 한국안전학회지 Vol.17 No.3

The object of this paper is to investigate collapse characteristics of CF/Epoxy(Carbon Fiber/Epoxy resin)composite tubes on the change of interlaminar number and fiber orientation angle of outer and to evaluate reappearance of collapse characteristics on the change of tension strength of fibers under static and impact axial compression loads. When a CF/Epoxy composite tube is crushed, static/impact energy is consumed by friction between the loading plate and the splayed fronds of the tube, by fracture of the fibers, matrix and their interface. In general, CF/Epoxy tube with 6 interlaminar number(C-type) absorbed more energy than other tubes(A, B, D-types). The maximum collapse load seemed to increase as the interlaminar number of such tubes increases. The collapse mode depended upon orientation angle of outer of CF/Epoxy tubes and loading status(static/impact). Typical collapse modes of CF/Epoxy tubes are wedge collapse mode, splaying collapse mode and fragmentation collapse mode. The wedge collapse mode was shown in case of CF/Epoxy tubes with 0˚ orientation angle of outer under static and impact loadings. The splaying collapse mode was shown in only case of CF/Epoxy tubes with 90˚ orientation angle of outer under static loadings, however in impact tests those were collapsed in fragmentation mode. So that, CF/Epoxy tube with 6 interlaminar number and 90˚ outer orientation angle presented to the optimal collapse characteristics.

다관절 로봇의 경로계획에 관한연구

전형주,정회범,심재홍 순천대학교 공업기술연구소 1990 工業技術硏究所論文集 Vol.4 No.-

In this study, the methods of the trajectory planning which satisfy the given constraints in the control systems, have the minimum segment­transition time, and reduce the deviation from straight­line path were investigated. The study was carried out in the joint space on the transition motion between two points and on the several segment motion along multiple points. The kinematic model of Rhino XR­2 robot was adopted in the simulation for the trajectory planning.

정면밀링에서 절삭저항과 표면거칠기에 관한 연구

위금식,정회범 順天大學校 1999 論文集 Vol.18 No.1

In this paper, the cutting resistance and surface roughness in deformed layer were tested for various cutting conditions of face milling. The face milling was performed on carbon steel(SM45C) and austenite stainless steel(STS304) by CNC machining center using 8 blades throw-away tip tool. Experimental tests were carried out by tool dynamometer and surface roughness tester. The results could be summarized ; 1. Cutting resistance in the direction of feed was influenced by depth of cut and cutting speed. 2. Surface roughness was increased at higher cutting speed when feed rate and depth of cut were held constant. 3. The optimal cutting conditions for face milling were 200 m/min cutting speed with 300 mm/min feed rate in SM45C, and 100 m/min cutting speed with 100 mm/min feed rate in STS304.

UCC를 통한 효율적인 안전교육 방안

한영근,김성훈,이동녘,구범회,김연범 明知大學校 産業技術硏究所 2008 産業技術硏究所論文集 Vol.27 No.-

There are many potential dangers around our life, but we are laking in the consciousness of safety because accidents do no happen frequently. If an accidents occurs, an ability to deal with it is so weak that it can be enlarges to a disaster. Therefore it is important to accustom ourselves to manage dangers and this can be realized by traing. In this study, the traditional traing methodologies are compared and analyszed in order to find an efficient traing way for the public. Also, we propose a traing method by using UCC(User Created Contest) which is a growing communication and content tool in the Internet environment nowadays.

Effects of Danggwieumja on the Healing of Full-Thickness Skin Injury in Rat

Bum Hoi Kim 한의병리학회 2011 동의생리병리학회지 Vol.25 No.5

Neuroprotecticve Effect of Rhei Rhizoma on Transient Global Ischemia in Gerbil

Bum-Hoi Kim(김범회),Hyuk-Sang Jung(정혁상),Ran Won(원란),Ji-Ho Park(박지호),Chul-Hun Kang(강철훈),Nak-Won Sohn(손낙원) 대한한의학회 2002 대한한의학회지 Vol.23 No.3