• Journal of Korea Water Resources Association
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• v.33 no.S1
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• pp.28-36
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• 2000

A TIN, Triagulated Irregular Network, based topographic modeling method and a distributed rainfall-runoff model using the topographic representation is presented. In the TIN based topographic representation, a watershed basin is modeled as a set of contiguous non-overlapping triagular facets : the watershed basin is subdivided according to streamlines to deal with water movement one-dimensionally ; and each partitioned catchment is approximated to a slope element having a quasi-three-dimensional shape by using cubic spline functions. On an approximated slope element, water movement is represented by combined surface-subsurface kinematic wave equations considering a change of slope gradient and slope width. By using the distributed rainfall-runoff model, the effects of spatial variability of soil properties on runoff response are examined.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.505-505
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• 2000

Controlling the process by PID controller is widely used in industry by applying Ziegler-Nichols method in analyzing parameter of the controller. However, in fact. it is still necessary to tune parameter in order to obtain the best process response. This paper presents a Self-Tuning PID controller utilizes the personal computer to synthesize and analyze controller parameter as well as tune for appropriate parameter by using Dahlin method and Extrapolation. Experimental results using a Self-Tuning PID controller to control water level and temperature, it is found that the controller being developed is able to control the process very effectively and provides a good response similar to the controller used in the industry.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.421-421
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• 2000

In this paper, robust two-degree-of-freedom controller for satellite antenna system which tracks reference signal is designed. Two-degree-of-freedom controller consists of a prefilter and a feedback controller to solve trade-off between robust stability and command response. The feedback controller is designed from specifications like stability, disturbance rejection and robustness via H$_{\infty}$ design technique. In the sequel, H$_2$ optimal prefilter is introduced to improve the command response. This suggests a two-step design, with different types of performance specifications at each stage. In practical problems, this may easily lead to a prefilter of unacceptably high order. In order to avoid high order prefilter we use a particular structure in which both the prefilter and the feedback controller share the same dynamics. H$_2$-prefilter technique proposed in this paper is verified by simulation.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.465-465
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• 2000

The paper presents the fuzzy control technique to adjust the gain schedule in the fuzzy controller. The micro computer is designed to the fuzzy controller to execute the proportional gain with the data of the error and speed command. The gain schedule is the fuzzy set which execute based on the fuzzy rule. The gain schedule from the fuzzy controller is fed to the sinusoidal pulse width modulation (SPWM) inverter for control the response and speed of the induction motor. The induction motor coupling to the DC motor and tachogenerator which DC motor as a load. The test result of the fuzzy control technique in the open loop control, it provides a good response and in the closed loop control it can control speed in the any condition of load design

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.405-405
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• 2000

We designed the artificial olfactory sensing system (Electronic Nose) using MOS type sensor array fur recognizing and analyzing odour. The response of individual sensors of sensor array, each processing a slightly different response towards the sample volatiles, can provide enough information to discriminate between sample odours. In this paper, we applied clustering algorithm for dimension reduction, such as linear projection mapping (PCA method), nonlinear mapping (Sammon mapping method) and the combination of PCA and Sammon mapping having a better discriminating ability. The odours used are VOC (Volatile chemical compound) and Toxic gases.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.500-500
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• 2000

In this paper, we deal wit,11 a simple tim varying feedforward compensator in order to decrease the amount of undershoots and overshoots on the step response. This compensator makes the step type input be a ramp input with saturation for 0 $\leq$ t < $\alpha$. It will be shown that the system with the feedforward compensator has small amount of undershoot and overshoot at the price of rise time. Also, provided the system properly stable, the influence of the design parameter $\alpha$ on the step response of the system with the feedforward compensator is investigated in the current paper.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.361-361
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• 2000

In the 2-mass system with flexible shaft, a torsional vibration is often generated because of the elastic elements in torque transmission as the newly required speed response which is very close to the primary resonant frequency. This vibration makes it difficult to achieve quick responses of speed and disturbance rejection. In this paper, 2-mass system is designed by using pole placement based on optimal control theory fur fast speed response and torsional vibration elimination and using neural network for disturbance rejection in particular. The simulation results show that the proposed controller based on neural network and full state feedback controller has better performance than 려ll state feedback controller, especially fur disturbance rejection.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.136-136
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• 2000

The direct drive servo valve(DDV) is composed of a DC rotor, link, valve spool and displacement sensor(LVDT) where the spool is directly coupled to the DC motor through the link. Since the DDV is a kind of one-stage valve, the robust controller is required to overcome the flow force effect on the spool motion. The mathematical equations are derived and the stability, accuracy and response speed of a DDV are investigated analytically using a linearized system block diagram. Proportional control, PID control. Time-Delay control, Sliding Mode control, and Proportional control using the load pressure are applied to DDV to find which one shows the best control performance. The digital computer simulation results show that the proportional control using the load pressure satisfies the design requirement of response speed and steady state error regardless of the variation of load pressure,

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2000.11a
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• pp.148-154
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• 2000

To do this study, we produced cooling vest newly. Rectal temperature was ascended approximately from 37.2$^{\circ}C$ to 38.05$^{\circ}C$ in lab, but wearing cooling vest, the temperature was descended 0.2 while wearing developed product compare with existing product. Mean skin temperature which was showed distribution from 32.8∼36.5$^{\circ}C$, it was descended 1.0∼1.1$^{\circ}C$, while wearing cooling vest and comparing with existing product, wearing developed product was lower 0.5$^{\circ}C$, While wearing developed product, it was found that they had lower tendency than exiting product. Specifically in case of temperature within clothing(chest) 0.2∼2.0$^{\circ}C$ in case of humidity within clothing 2∼8% RH. Facts from above we confirmed that clothing microclimate had been improved and space was happened between body and garment in order to control. In subjective sensation, existing product made negative response during experiment period from participants, but developed product was nearing to comfortable area.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.38-44
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• 2000

An oil hydraulic line is modeled in which a pipe or two pipes of different size connected in series and terminated in a chamber, i.e. a composite line system. The frequency response characteristics are investigated analytically and experimentally. The theoretical analysis is base on unsteady laminar flow of a viscous compressible fluid. It is generally difficult to obtain exactly the frequency equation of these lines system and its solutions in consideration of viscosity of hydraulic fluid, because the diameters of two pipes and length are different. The effect of the position where the cross-sectional area of changes suddenly, the inner radius of pipe and the volume of terminal chamber on the frequency characteristics of this composite line system are also described.