비선형 보상기와 외란관측기를 이용한 공기압 실리더의 위치제어

장지성,Jang, Ji-Seong 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.9

A position controller which can achieve a specified dynamic performance irrespective of the different operating position of the pneumatic cylinder is proposed. The position controller developed in this paper is composed of a nonlinear compensator and a disturbance observer. The nonlinear compensator which feeds back position, velocity and acceleration is derived from the nonlinear dominating equations of the position control system to compensate for variation of dynamic characteristics of a pneumatic cylinder according to the change of the operating position. The disturbance observer including a simplified linear model is designed to reduce the effect of model discrepancy in the low frequency range which cannot be suppressed by the nonlinear compensator. The results of the experiments show that the position control performance maintains a designed performance regardless of the variations of an operating position of the pneumatic cylinder.

반도체 메모리 제작장비에 있어서의 공기압 구동장치의 응용

장지성,강보식,조정대,Jang, Ji-Seong,Gang, Bo-Sik,Jo, Jeong-Dae 재료연구소 1999 機械와 材料 Vol.11 No.2

CIGS 박막태양전지 기술 및 동향

장지성,정중희,Jang, Ji-Seong,Jeong, Jung-Hui 한국전기전자재료학회 2016 전기전자재료 Vol.29 No.11

경영사례-최소 투자로 경제적인 돈사시설 설치하는 법

장지성,Jang, Ji-Seong 대한양돈협회 1995 養豚 Vol.17 No.1

A Method of Accurate Position Control with a Pneumatic Cylinder Driving Apparatus

Ji-Seong JANG(장지성),Dae-Kwon Koh(고대권),Young-Bok Kim(김영복) 한국동력기계공학회 2006 한국동력기계공학회 학술대회 논문집 Vol.- No.-

In this paper, a method of accurate position control using a pneumatic cylinder driving apparatus is presented. To overcome the friction force and the effect of transmission line, low friction type cylinder applied externally pressurized air bearing structure is used and two control valves attached both side of the cylinder directly. To compensate nonlinear characteristics of control valves, linearized control input derived from the relation between control input and effective area of control valve, and dither signal is applied to the valve. The controller applied to the pneumatic cylinder driving apparatus is composed of a state feedback controller and a disturbance observer. Experimental results show that the effectiveness of the proposed method and position control error of 5J.lI11 accuracy could be obtained easily.

공기압 압력용기의 압력제어

장지성(Ji-Seong JANG),고대권(Dae-Kwon Koh),김영복(Young-Bok Kim) 한국동력기계공학회 2006 한국동력기계공학회 학술대회 논문집 Vol.- No.-

In this study, a robust controller to control pressure in a pneumatic pressure vessel with a long transmission line is proposed. Frequency response of transmission line using compressible fluid is changed by the flowing state of the fluid. So, if a fixed gain controller designed based on a model supposed the flowing state to a specific state, the performance of the control system could be degraded because of the modelling error. The controller designed in this study is composed of two parts. One is a feedback controller to improve a feedback characteristics and to compensate the influence of the variation of transfer characteristics of a transmission line owing to the change of flowing state and the other is a feedforward controller to regulate command following performance. The experimental results with the designed controller show that the robustness of the control system is achieved regardless of the change of the model of the transmission line. Therefore, the designed controller can be utilized for the performance improvement of a pressure control system with a long transmission line using compressible fluid.

Accurate Positioning of a Pneumatic Servo System

Ji-Seong Jang(장지성) 한국해양공학회 1998 韓國海洋工學會誌 Vol.12 No.4

본 논문에서는 공기압 액튜에이터를 사용한 정밀 위치 시스템을 이용하여 정밀 위치 제어를 수행한다. 본 논문에서 사용된 정밀 위치 제어 시스템은 저 마찰형 서보 테이블과 고속 제어 밸브로 구성되어 진다. 서보 테이블은 공기압 액튜에이터의 위치제어 성능에 악영향을 미치는 구동 피스톤의 씰(seal) 부분의 마찰력을 보상하기 위하여 공기압 베어링 기구를 채택하고 있다. 제어 밸브는 대역폭이 100㎐ 이상인 고속 제어 밸브를 사용했다. 그 결과, 구동 피스톤의 마찰력을 감소시킨 정밀 위치 제어 시스템을 사용함에 의하여 컨트롤러의 설계가 용이하고, 위치 제어 오차가 ±10 ㎛ 이내의 정밀한 위치제어가 가능함을 보였다.

산수화 화면형식과 구도법의 활용에 대한 연구

장지성(Jang Ji-Seong) 한국미술교육학회 2004 美術敎育論叢 Vol.18 No.1

전통미술교육은 전통문화의 이해에 그 초점을 맞추어야 한다고 생각하며, 이를 위해 전통미술의 여러 부분에서 활용할 수 있는 다양한 내용과 프로그램이 개발되어야 한다. 전통미술의 중요한 영역 중에 하나인 산수화가 전형적인 화면형식과 구도가 전통적으로 하나의 틀로써 구성되어지고, 이어져 온 것은 단순히 화면형식과 구도의 다양한 변화라는 부분뿐만 아니라, 기본적으로 산수화의 사상적인 배경, 전통적인 생활환경이나 산수화를 선호하고 즐겼던 감상자의 기호에 의해 구축된 것이다. 따라서 산수화의 전형적인 화면 형식과 구도를 이해하고 이를 활용한 표현활동을 계획하고 실행할 수 있다면, 전통회화의 표현방식과 내용을 보다 잘 이해할 수 있으리라 판단되며, 이러한 교육을 통해서 미술과 교육과정에서 요구하는 ‘전통문화의 이해’라는 측면에 부합하는 하나의 프로그램을 구성할 수 있다고 생각한다. 이에, 이 글에서는 산수화의 화면 형식 중에 대표적인 네 가지의 화면형식과 이에 따른 구도법을 살펴보고 현장에서 활용할 수 있는 가능성에 대하여 탐색해보고자 하였다. While teaching the techniques of traditional painting, we should focus on understanding the traditional culture. For that purpose, various contents and programs which can be used for traditional painting in different ways should be developed. How the entire form and the composition of landscape painting in the traditional painting could be harmonized as the frame of the picture was not only by many changes of a form and a composition. Basically, this tendency was established by some factors such as the historical background of a landscape picture, traditional life style and the taste of an art lover who enjoyed making a landscape picture and appreciating it. Therefore, if we understand the typical forms and composition of landscape painting and if we can use this knowledge we also would understand better how to create a picture in traditional ways and how to express its spirit. Through education we think that we can develop a program corresponding to the purpose of ‘Understanding of traditional art’ which is required for the art education course. Thus, in the study, we consider the four representative painting forms out of many forms of landscape painting and the possibilities of a right composition when we create a landscape picture.

공기압 구동장치를 이용한 정밀위치제어

장지성(Ji Seong Jang) 유공압건설기계학회 2015 드라이브·컨트롤 Vol.12 No.4

The accurate position control of pneumatic driving apparatus is considered in this paper. In pneumatically actuated positioning systems, accurate positioning as an electrical servo has been known to be difficult because of the friction force and compressibility of the air. For good control performance of the pneumatic system, an actuator mounted with externally pressurized air bearings is produced to compensate for friction force. For the controller design, the governing equation of the pneumatic driving apparatus is derived. In order to reduce the nonlinear characteristics of the control valve, linearized control input is derived from the relation between the effective area of the valve and the control input. The experimental results are presented to show the results of the improved position control of the pneumatic driving apparatus.

산수화의 시방식 (視方式) 연구

장지성(Ji Seong Jang) 한국기초조형학회 2000 기초조형학연구 Vol.1 No.2

A set form is required to see something as its object is expressed in a picture. There are also some specifications of such form for oriental landscape paintings, which are quite different from those for western landscape paintings. In oriental landscape painting, which has its basis in the Chinese Laotzu-Chuangtzu philosophy that emphasized being united with nature for the happiness of the human being, to paint the landscape and appreciate it is considered as an expression of the intent or wish to be back to nature. In the world of such a concept, a picture seen in scale` not only shows a beautiful scene, but also comprises a small universe` in which natural beauty is expressed, hidden, and far off. To embody this concept in oriental painting, the conceptual specifications for the visual points in a picture are not fixed, but are shared and movable to the left, right, up, or down in all directions at your own will. Each individual scene is thought of or kept in mind to embody and comprehensively express all the points in a whole picture by mobilizing various visual points. A bugamsi, a kind of point of aerial view like a bird`s eye view, is required to comprehend and embody all the visual points.