• Korean Journal of Mathematics
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• v.27 no.4
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• pp.861-877
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• 2019

The aim of this paper is to extend some existing fixed point results for asymptotically regular mappings to fuzzy metric spaces. For this purpose some contractive type conditions with respect to an altering distance function are used. Some new common fixed point results have been derived for such mappings. We provide suitable examples to justify our study.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.58
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• pp.29-39
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• 2000

This paper concerns the location of the transit point between adjacent loops and guide direction of loops in the tandem configuration manufacturing system. The tandem configuration has been used to solve control problems like the vehicle dispatching and traffic control. The transit point between loops needs to deliver the parts from one loop to another. The location of transit point between adjacent loops and direction of loops must be determined to minimize the total travel time of parts in the manufacturing system. The model formulation is developed, a numerical example is shown.

• Journal of Computational Design and Engineering
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• v.3 no.4
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• pp.322-329
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• 2016

The advent of high-performance terrestrial laser scanners has made it possible to capture dense point-clouds of engineering facilities. 3D shape acquisition from engineering facilities is useful for supporting maintenance and repair tasks. In this paper, we discuss methods to reconstruct box shapes and polygonal prisms from large-scale point-clouds. Since many faces may be partly occluded by other objects in engineering plants, we estimate possible box shapes and polygonal prisms and verify their compatibility with measured point-clouds. We evaluate our method using actual point-clouds of engineering plants.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.617-621
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• 2001

This paper presents a maximum power point tracking algorithm for Photovoltaic array using only instantaneous output current information. The conventional Hill climbing method of peak power tracking has a disadvantage of oscillations about the maximum power point. To overcome this problem, we have developed a algorithm, that will estimate the duty ratio corresponding to maximum power operation of solar cell. The estimation of the optimal duty ratio involves, finding the duty ratio at which integral value of output current is maximum. For the estimation, we have used the well know Lagrange's interpolation method. This method can track maximum power point quickly even for changing solar insolations and avoids oscillations after reaching the maximum power point.

• The Journal of Korean Physical Therapy
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• v.22 no.5
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• pp.33-38
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• 2010

Purpose: This study examined the activation of the rectus abdominis (RA), external abdominal oblique (EO), transversus abdominis, internal abdominal oblique (TrA/IO), and Multifidus (MF) muscles while stabilization exercise was performed in a four-point kneeling position. Methods: Experiments were conducted on 21 healthy male adults (mean age=25.29 years) who voluntarily agreed to participate in the study. Each subject was instructed regarding maximal voluntary contractions (MVC) and stabilization exercise in four-point kneeling. While MVC and stabilization exercise of individual muscles were being performed, activation of the muscles was measured using surface electromyography (EMG). Activation of the muscles while performing stabilization exercise in four-point kneeling was normalized to a percentages of the MVC. Results: Left RA, right TrA/IO, right and left MF muscles showed significant differences among the positions. Conclusion: Selecting an optimal position can aid subjects on physical conditions while performing stabilization exercises in the four-point kneeling position.

• Journal of the Korea Computer Graphics Society
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• v.5 no.2
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• pp.1-7
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• 1999

We present an algorithm to reconstruct a pipe surface from a set of unorganized points. A pipe surface is defined by a spine curve and a radius of a swept sphere. In this paper, by using the shrinking and moving least-squares methods, a point cloud is reduced to a thin curve-like point set that can be easily approximated with a spine curve of a pipe surface. The distance between a point in the thin point cloud and a corresponding point in the original point set represents the radius of a swept sphere of a pipe surface.

• International Journal of Precision Engineering and Manufacturing
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• v.1 no.1
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• pp.15-21
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• 2000

This study presents a procedure for analyzing chip-tool friction and shear processes in 3-D cutting with a single point tool. The edge of a single point tool including a circular nose is modified to an equivalent straight edge, thereby reducing the 3-D cutting with a single point tool to the equivalent of oblique cutting. Then, by transforming the conventional coordinate systems and using the measurements of three cutting force components, the force components on the rake face and shear plane of the equivalent oblique cutting system can be obtained. As a result, the chip-tool friction and shear characteristics of 3-D cutting with a single point tool can be assessed.

• Journal of Biosystems Engineering
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• v.17 no.3
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• pp.223-228
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• 1992

This study was conducted to develop an electro-hydraulic three-point hitch control system using an electro-hydraulic servo valve and microcomputer and to investigate the performance of the three-point hitch control system through indoor and field experiments. 1. The results from indoor experiments coincided with those from computer simulation reported in the previous paper. However, the draft control with the value 4 of Kd showed a slight sustained oscillation after it reached the draft set. 2. From the field experiments, it appeared that the RMS errors increased with the ground speed of tractor. In position control, the three-point hitch control system with electro-hydraulic servo valve showed better performance than that with on-off electro-magnetic valve in the ground speed less than 1.6 m/s. In draft control, however, there was no significant differece in performance between those two systems. 3. In depth control, the both types of electro-hydraulic three-point hitch control system showed better performance than the conventional mechanical-hydraulic three-point hitch control system.

• Communications of the Korean Mathematical Society
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• v.33 no.3
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• pp.943-960
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• 2018

Our aim is to introduce the notion of a parametric $N_b-metric$ and study some basic properties of parametric $N_b-metric$ spaces. We give some fixed-point results on a complete parametric $N_b-metric$ space. Some illustrative examples are given to show that our results are valid as the generalizations of some known fixed-point results. As an application of this new theory, we prove a fixed-circle theorem on a parametric $N_b-metric$ space.

• Journal of Electrochemical Science and Technology
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• v.8 no.3
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• pp.244-249
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• 2017

This paper presents the results of an investigation into the isoamperic point of cyclic voltammograms, which is defined as the singular point where the voltammograms of various scan rates converge. The origin of the unique point is first considered from a theoretical perspective by formulating the voltammetric curves as a system of linear equations, the solution of which indicates that a trivial solution is only available at the potential at which the net current is zero during the reverse potential scan. In addition, by way of a mathematical formulation, it was also shown that the isoamperic point is dependent on the switching potential of the potential scanning. To validate these findings, theoretical and practical cyclic voltammmograms were studied using finite-element based digital simulations and 3-electrode cell experiments. The new understanding of the nature of the isoamperic point provides an opportunity to measure the charge transfer effects without the influence of the mass transfer effects when determining the thermodynamic and kinetic characteristics of a faradaic system.