• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.10
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• pp.875-880
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• 2008

In this paper, we deal with the TLP evaluation results for GGNMOS in ESD protection device of conventional CMOS process. An evaluation parameter for GGNMOS is that repeatability evaluation for reference device($W/L=50\;{\mu}m1.0\;{\mu}m$) and following factors for design as gate width, number of finger, present or not for N+ gurad -ring, space of N-field region to contact and present or not for NLDD layer. The result of repeatability was showed uniformity of lower than 1 %. The result for design factor evaluation was ; 1) gate width leading to increase It2, 2) An increase o( finger number was raised current capability(It2), and 3) present of N+ gurad-ring was more effective than not them for current sink. Finally we suggest the optimized design conditions for GGNMOS in evaluated factor as ESD protection device of conventional CMOS process.

• International Journal of Concrete Structures and Materials
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• v.2 no.2
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• pp.99-105
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• 2008

Southern exposure test specimens were used to evaluate corrosion performance of epoxy-coated reinforcing bars in chloride contaminated concrete by electrochemical impedance spectroscopy method. The test specimens with conventional bars, epoxy-coated bars and corrosion inhibitors were subjected 48 weekly cycles of ponding with sodium chloride solution and drying. The polarization resistance obtained from the Nyquist plot was the key parameter to characterize the degree of reinforcement corrosion. The impedance spectra of specimens with epoxy-coated bars are mainly governed by the arc of the interfacial film and the resistance against the charge transfer through the coating is an order of magnitude higher than that of the reference steel bars. Test results show good performance of epoxy-coated bars, although the coatings had holes simulating partial damage, and the effectiveness of corrosion-inhibiting additives. The corrosion rate obtained from the impedance spectroscopy method is equivalent to those determined by the linear polarization method for estimating the rate of corrosion of reinforcing steel in concrete structures.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.497-500
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• 2006

An theoretical analysis on the electro-osmotic flow in a 2-dimensional slit, that is induced by an external electric field acting on the electrical double layers near the slit wall, was performed. Especially, although there were many studies on the interacting electrical double layers, it was found in this study that they have several physical or mathematical fallacies. To resolve these, the general solution on the charge-regulating slit with the height as a parameter was obtained. The results of this work can provide the electrokinetic solution of nanoscale slit with the electrical double layer interaction as well as that of microscale slit without the interaction and can be used as the benchmark of a numerical analysis and the reference of electrokinetic flow path design.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.10
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• pp.911-917
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• 2000

As many sensors and actuators are used in various automated systems, the application of network to real-time distributed control system is gaining acceptance in many industries. In order to take advantages of networking, however, the network should be carefully designed to satisfy real-time distributed control. This paper presents an implementation method of closed-loop control using Profibus-FMS. In order to implement a closed-loop control system, we used industrial computers with Profibus-FMS network cards and a DC servo motor. Through various experiments, the step response of the control system with network was compared with the reference response without network.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.1-6
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• 1991

This paper is concerned with the design of a robust tracking controller using a state observer on a robotic manipulator under the disturbance. The controller is designed to follow a step or ramp reference input without steady state error in the presence of a disturbance and a system parameter variation. In most cases, since all the state vectors are not measured, unmeasurable state vectors must be estimated or reconstructed. A reduced order observer is proposed to estimate unmeasurable state vectors of the non-linear system. Some problems are caused by the Coulomb friction, the disturbance, and the spring effect of a link between the drive motor and the manipulator arm. The state variables, directly measured and estimated by the reduced order observer, are fed back to the controller. When the robot system exhibits the 'limit cycle, the feedback gains initially obtained by optimal control theory are changed. As a result, the limit cycle is eliminated by the new controller gains,

• 제어로봇시스템학회:학술대회논문집
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• 1988.10b
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• pp.981-986
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• 1988

A controller synthesis procedure for precise tracking of reference inputs in the sense of spheres is applied to a 3 d.o.f. robotic manipulator. This methodology applies to a class of nonlinear systems with input uncertainty and parameter uncertainty. The 3 d.o.f. manipulator to be controlled is subjected to varying payloads and is required to follow specified joint trajectories to within prespecified tolerances. The design procedure above lends itself naturally to this type of control problem. The appeal of such a design procedure lies on a special decomposition which exploits linear control theory on the one hand and facilitates a separate treatment of the effects of nonlinearities and the uncertainties on the other.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.40 no.1
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• pp.124-129
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• 2003

A novel watermark registration method based on Radon transform for self-referencing watermark is presented. The novel method was successful in registering the watermark of the image that has undergone affine transformations and severe lossy compression, whereas the conventional method based on peak detection failed to register the watermark.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.6 no.3
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• pp.53-57
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• 2007

This paper presents a geometrical error compensation of tool alignment for B axis controlled machine. In precision machining, tool alignment is crucial parameter for machined surface. To decrease tool alignment error, plus tilted tool from B axis center is touched to reference work piece and checked the deviation from original position. Same process is performed in minus tilt. Comparing these 2 touch positions, wheel alignment error in X axis and Z axis can be calculated on B axis center. Experimental results show that this compensation method is efficient to correct tool alignment.

• Ocean Systems Engineering
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• v.1 no.3
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• pp.207-222
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• 2011

A stabilized incompressible smoothed particles hydrodynamics (ISPH) method is utilized to simulate free falling rigid body into water domain. Both of rigid body and fluid domain are modeled by SPH formulation. The proposed source term in the pressure Poisson equation contains two terms; divergence of velocity and density invariance. The density invariance term is multiplied by a relaxed parameter for stabilization. In addition, large eddy simulation with Smagorinsky model has been introduced to include the eddy viscosity effect. The improved method is applied to simulate both of free falling vessels with different materials and water entry-exit of horizontal circular cylinder. The applicability and efficiency of improved method is tested by the comparisons with reference experimental results.

• 제어로봇시스템학회:학술대회논문집
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• 1995.10a
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• pp.460-463
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• 1995

The present paper studies a robot manipulator's contact tasks on the uncertain flexible objects. The flexible object's distributed parameter model is approximated into a lumped "position state-varying" model. By using the well-known nonlinear feedback compensation, the robot's control space is decomposed into the position control subspace and the object's torque control subspace. The optimal state feedback is designed for the position loop, and the robot's contact force is controlled through controlling the resultant torque on the object using model-reference simple adaptive control. Experiments of a PUMA robot interacting with an aluminum plate show the effectiveness of this control approach. approach.