• 대학교육
• /
• s.142
• /
• pp.36-42
• /
• 2006

정부주도적인 획일정책이나 지시명령적 관여 등 80년대의 정치.사회적 상황이나 시대적 배경이 대교협 발족의 근본적 동기가 되었다고 본다. 대학들은 근원적으로 그 자체가 하나의 자치기구이며, 학문공동체이며, 자기통제기관이다. 이러한 대학의 속성을 살리기 위해 정부와 대학 간의 협의조정기구로서 협의체의 필요성을 깨닫고, 우리나라 대학의 자율성 신장을 위해 하나의 이정표를 세웠다는 점에서 대교협의 큰 의의가 있다고 평가된다.

• Journal of the Korean Society for Precision Engineering
• /
• v.15 no.10
• /
• pp.180-192
• /
• 1998

This paper introduces a new self-organizing fuzzy logic controller (SOFLC) for precision contour machining in the presence of large disturbances which adjusts both input and output membership functions simultaneously. The parameters of the proposed controller are self-tuned in real-time according to a continuous measurement of the performance of the controller itself and estimated disturbance values. The proposed controller as well as a conventional fuzzy logic controller and a PID controller were simulated and implemented on a 3-axis milling machine in contour milling. Both the simulations and experiments show that the self-organizing fuzzy logic controller has superior performance in terms of contour tracking accuracy compared with the other two controllers.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.5 no.4
• /
• pp.101-110
• /
• 1995

In this paper, a DC servo motor position control system based on acceleration control is proposed. The proposed control system consists of an acceleration controller and an auto-tuqing fuzzy PID controller. The auto-tuning fuzzy PID controller provides corrections for an acceleration reference to remove the effect of parametric uncertainties. And it comprises of the expert system which performs the automatic tuning of the PID controller parameters and the conventional PID controller. Expermental results demonstrate strate thi~tth e proposed overall control system has robust properties and good control performances with regard to unmeasurable disturbances and parameter variations. Therefore, the proposed control scheme enhances the applicability of an acceleration control approach and especially performs accurate position control under such an operating environment that model uncertainties exist and/or load, etc. change significantly.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.25 no.8
• /
• pp.1308-1316
• /
• 2001

A hybrid type master system is proposed to take the advantage of the link mechanism and magnetic levitation mechanism without using a force sensor. Two different types of electromagnetic actuators, moving coil type and moving magnet types are used to drive the master system which is capable of 4-DOF actuation. It is designed that the rotation motions about x-y axis are decoupled and the whole system is represented by simple dynamic equations. The force reflection is achieved by using the simple relation between the force and applied current and position. The simulation and experimental results are presented to show its performance.

• Resources Recycling
• /
• v.12 no.6
• /
• pp.26-31
• /
• 2003

The power loss characteristics of Mn-Zn ferrite were observed with the sintering temperature. In case of $1150 ^{\circ}C$ sintering, the core loss increased with measuring temperature, and does not have minimum value at the point where the magnetocrystalline anisotropy be 'zero'. This reason mainly due to the change of core loss mechanism with grain size which affects residual loss. The grain size and sintered density slightly increased with equilibrium oxygen partial pressure at$ 1150 ^{\circ}C$ sintering. The resistivity and initial permeability showed no significance with atmosphere, these results due to complex effect of $Fe^{2+}$ concentration and microstructure change. The core loss at $100^{\circ}C$ decreased as the equilibrium oxygen partial pressure increased.e increased.