• Journal of Institute of Control, Robotics and Systems
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• v.20 no.8
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• pp.789-794
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• 2014

This paper presents some real performance of two typical bilateral teleoperation benchmark tasks: peg-in-hole and surface tracking tasks. The tasks are performed by an energy-bounding algorithm in the master control and position-based impedance algorithm in the slave control. Performance is analyzed for the position-force tracking capabilities from free space motion to surface contacting motion. In addition, preliminary user performance is evaluated by measuring the completion time and maximum/average contact forces. The quality of the measured performance is also compared with that of other existing approaches.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.329-334
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• 1987

The purpose of this study is to monitor and control the back bead width in arc welding with consumable electrode for reduction of the occurrence of weld defect. The temperature of a point on the weldment surface is selected, as a monitoring parameter, and measured by an optical infra-red sensor. The correlation between the back bead width and the surface temperature is experimentally obtained for various thicknesses of the weldment. The welding travel speed and the surface temperature are taken, respectively, as an input and an output of the welding process under the stable condition of arc. A PI control scheme to maintain the surface temperature at the desired level is proposed by the experimental study.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.125-125
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• 2000

An Empirical approach to determine a road-surface condition is presented The road-surface condition thus provided includes the detection of not only friction coefficient, but also abrupt surface-profile changes such as pitfalls and bumpers The former plays a key role in establishing the appropriate control strategy, while the latter allows to minimize unnecessary brake intervention induced by the aforementioned jut. In this paper, we use an empirically chosen variable, namely. the time-rate of change of vehicle speed estimated from the point where ABS engaged to the point where measurement taken Experimental results shoe that the proposed method is effective to infer various control variables critical for the control of ABS.

• Journal of dental hygiene science
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• v.12 no.1
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• pp.39-44
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• 2012

For the purpose of examining the dental biofilm reduction effect and control difficulty level through a dental biofilm control program in this study, the total of 131 medical records (82.9%) were used for the final analysis upon excluding the records that were not suitable for this study among the records of 158 persons for the medical records of clinical hygiene case reports that were submitted from 2006 to 2011 by students at the Department of Dental Hygiene at N University located in Chungnam region. The result of examining the dental biofilm reduction effect according to the visit number when conducting a dental biofilm control program showed that the dental biofilm index reduced meaningfully as the visit number increased. However, in the case of those that visited for 7 sessions, the level of reduction was not statistically meaningful. For the purpose of comparing the dental biofilm index mean per area of teeth during the final session visit of dental biofilm control program, the area of teeth was classified into labial/buccal surface, lingual/palatal surface and proximal surface, and the dental biofilm index of lingual/palatal surface was the highest with 26.5%. The result of measuring the dental biofilm of maxilla/mandible revealed meaningful differences between the dental biofilm index of maxilla and mandible. The result of analyzing the dental biofilm index of labial/buccal surface, lingual/palatal surface and proximal surface revealed meaingful differences among the dental biofilm index of labial/ buccal surface, lingual/palatal surface and proximal surface.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.862-867
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• 1997

A 5-axis NC milling technology is presented on ruled surface. Problems in 5-axis NC machining are such as tool interference,tool collision and change of tool attitude,etc. The change of tool attitude causes rotation of cutter and variation of feedrate to overcut part surface. This poor control of tool attitude is the primary problem in multi-axis NC milling. This paper observes ruled surface for control of tool attitude. Ruled surface is composed of directrix and ruling, line of constant magnitude. Directrix corresponds to points on part surface and Ruling cutting tool. Trajectory of tool movement corresponds to ruled surface.

• Transactions of Materials Processing
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• v.12 no.6
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• pp.572-581
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• 2003

In this paper, an automatic surface construction method based on B-spline surface and scalar field theory is proposed to generate the extrusion die surface of non-symmetric H-and U-shaped sections. The isothermal lines and stream lines designed in the scalar field are introduced to find the control points which are used in constructing B-spline surfaces. Intersected points between the isothermal lines and stream lines are used to construct B-spline surfaces. The inlet and outlet profiles are precisely described with B-spline curves by using the centripetal method for uniform parameterization. The extrusion die surface is generated by using the cubic curve interpolation in the u-and v-directions. A quantitative measure for the control of surface is suggested by introducing the tangential vectors at the inlet and outlet sections. To verify the validity of the proposed method, automatic surface generation is carried out for extrusion die of non-symmetric H-and U-shaped sections.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.251-252
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• 2007

• Journal of Astronomy and Space Sciences
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• v.26 no.4
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• pp.651-658
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• 2009

Nonlinear sliding surface design in variable structure systems for spacecraft attitude control problems is studied. A robustness analysis is performed for regular form of system, and calculation of actuator bandwidth is presented by reviewing sliding surface dynamics. To achieve non-singular attitude description and minimal parameterization, spacecraft attitude control problems are considered based on modified Rodrigues parameters (MRP). It is shown that the derived controller ensures the sliding motion in pre-determined region irrespective of unmodeled effects and disturbances.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1295-1297
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• 2007

In this study, we report that the characteristics of OTFTs can be improved by the UV exposure of the surface of the synthesized photo-reactive gate insulator, and be optimized by controlling the exposure time. As a gate dielectric, the modified PVP was prepared by substituting hydroxyl group in PVP with cinnamoyl group. The synthesis details and the effects of the modified PVP on the device performance are discussed.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.111.2-111
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• 2001

The research focuses on controlling a gap to measure the surface defect in semi-conductor fabrication device. The measurement is available accompanying a near field image gap control. In this article, a pneumatic servo system is adopted for the near field gap control. The advantage of the pneumatic servo system is on the preventing the possibility of contacting the device to the wapper surface, fence arising fatal damage. Furthermore, the air from the pneumatic system blows the some particle on the wapper during controlling. The target gap is less than 20 $\mu$m and the gap should keep same amount while the device moves around the surface. The experiment by the pneumatic servo control system is done by employing a simple PID control, and the tracking performance is remarkably verified. The target gap is set from 10 $\mu$m to 100 $\mu$m ...