• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.481-484
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• 1990

Normal operation when deeply submerged is a relatively easy task, and human operator control can often provide adequate performance. Near surface depthkeeping, on the other hand, is difficult to both man and machine. Because of the inherent limitation of the human operator, manual control may prove inadequate for near surface depthkeeping in some sea state. This paper describe the control algorithm of an automatic depth control system for submerged body that can be used for both near surface and deeply submerged depthkeeping operations. The computer simulations demonstrate the excellent depthkeeping performance of the controller under seaway effects.

• Proceedings of the KSME Conference
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• 2001.06b
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• pp.65-69
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• 2001

In this study, the deformation of the free surface motion of a magnetic fluid for the change in electromagnetic force is discussed. In case, magnetic fluid in characteristics of fluid adjusted to the opposite direction of the gravity direction. Thus, the device of a magnetic fluid proposed the complete zero-leakage Sealing and the surface actuator. The device of surface deformation as well comparison between numerical simulation and experiments as will be presented.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.11
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• pp.983-988
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• 2015

This paper details a new ultra-precise turning method for increasing surface quality, "Multi Point B Axis Control Method." Machined surface error is minimized by the compensation machining process, but the process leaves residual chip marks and surface roughness. This phenomenon is unavoidable in the diamond turning process using existing machining methods. However, Multi Point B axis control uses a small angle (< $1^{\circ}$) for the unused diamond edge for generation of ultra-fine surfaces; no machining chipping occurs. It is achieved by compensated surface profiling via alignment of the tool radial center on the center of the B axis rotation table. Experimental results show that a diamond turned surface using the Multi Point B axis control method achieved P-V $0.1{\mu}m$ and Ra 1.1nm and these ultra-fine surface qualities are reproducible.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.538-541
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• 2005

In tapping mode atomic force microscopy(TM-AFM). the vibro-contact response of a resonating tip is used to measure the nanoscale topology and other properties of a sample surface. However, the nonlinear tip-surface interact ions can affect the tip response and destabilize the tapping mode control. Especially it is difficult to obtain a good scanned image of high adhesion surfaces such as polymers and biomoleculars using conventional tapping mode control. In this study, theoretical and experimental investigations are made on the nonlinear dynamics and control of TM-AFM. To analyze the complex dynamics and control of the tapping tip, the classical contact models are adopted due to the surface adhesion. Also we report the surface adhesion is an additional important parameter to determine the control stability of TM-AFM. In addition, we prove that it is more adequate to use Johnson-Kendall-Roberts (JKR) contact model to obtain a reasonable tapping response in AFM for the soft and high adhesion samples.

• Korean Journal of Computational Design and Engineering
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• v.3 no.2
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• pp.103-112
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• 1998

In this paper insertion of numerous control points to be performed by using the Chebyshev polynomial root at the selection of knot vector. This method introduces a simple method of knot refinement and it is applied in a developed program. The Chebyshev roots exist densely in broth ends of the range and are proposed more effective knot refinement to modify a surface. Therefore, generated control points are relatively uniform in specified knot interval. In the surface generation, a local insertion of numerous control points are easily inserted by using the characteristic of Chebyshev polynomial roots at knot refinement. It is possible to create a complex surface with a single surface. The number of control point can be reduced by using the local insertion of control points in a required shape

• Journal of the Korean Society for Precision Engineering
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• v.15 no.3
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• pp.99-106
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• 1998

Recently, scientists introduced a new type of microscope capable of investigating nonconducting surfaces in an atomic scale, which is called AFM (Atomic Force Microscope). It was an innovative attempt to overcome the limitation of STM (Scanning Tunnelling Microscope) which has been able to obtain the image of conducting surfaces. Surfaces of samples are imaged with atomic resolution. The AFM is an imaging tool or a profiler with unprecedented 3-D resolution for various surface types. The AFM technology, however, leaves a lot of room for improvement due to its delicate and fragile probing mechanism. One of the room for improvements is gap control between probe tip and sample surface. Distance between probe tip and sample surface must be kept in below one Angtrom in order to measure the sample surface in Angstrom resolution. In this paper, AFM system modeling, experimental system identification and control scheme based on system identification are performed and finally sample surface is measured by home-built AFM with such a control scheme.

• Journal of Aerospace System Engineering
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• v.5 no.1
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• pp.1-6
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• 2011

It is very important to correctly set control surface linkage. But a lot of bad setting case has been seen in especially remote controled airplanes and middle size UAVs. In this paper, a three dimensional linkage from control surface to deflection sensor was analyzed kinematically and a position analysis was simulated using algebraic algorithm in terms of nonlinear error of deflection angle. Three correct settings of the linkage came out of this research. One is two-dimensional motion, another is link ratio of 1 and the other is that effective lever of the control surface should be perpendicular to a pushrod in their neutral position.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.8
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• pp.109-117
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• 2004

A study on gust load alleviation using aircraft control surface was performed. Aeroservoelastic model including control surface controller was formulated and validated by comparing the results of continuous gust response analysis with those of MSC/NASTRAN. Optimal control with output feedback was adopted for designing the control surface controller, and the effects of gust load alleviation was validated by performing the numerical simulation for the controller designed.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.1
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• pp.103-114
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• 2018

The operational concept of control systems on surface combatants has been changed from individual control for each system to integrated control for all systems due to computing technology development and crew reduction policy of navy. The purpose of this study is to identify current status of control technology, to analyze user requirement and to develop an architecture to support the conceptual change of ship control. An architecture, which integrates several control and monitoring systems on naval surface combatant, is proposed. The proposed architecture is focused on sharing network and computing resources related to user command, and reducing systems complexity. The architecture can be adopted to next surface combatants in Korean navy.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.8 no.2
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• pp.39-49
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• 2004

Model of the novel Surface motor (SFM) is briefly discussed, and two types of control method including two-order feedback circuit control, indirect acceleration feedback control are analyzed to solve unstable characteristic such as low damp and negative stiffness. The simulation results demonstrate that the system has plain amplitude and wide frequency band arranging from 0 to 8kHz with no resonant peak through indirect acceleration feedback control.