• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.3
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• pp.52-57
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• 1997

Electronic Speckle Pattern Interferometry(ESPI) using the Model 95 Ar. laser, a video system and an image processor was applied to the in-plane displacement measurements. Unlike traditional strain gauges or Moire method, ESPI method requires no special surface preparation or attachments and can be measured in-plane displacement with no special surface preparation or attachments and can be measured in-plane displacement with no contact and real time. In this experiment specimen was loaded in parallel with a loadcell. The specimen was the cold rolled steel sheet of 2mm thickness, which was attached strain gauges. The study provides an example of how ESPI have been used to measure strain displacement in this specimen. The results measured by ESPI compare with the data which was measured by strain gauge method in tensile testing.

• Journal of the Korean Society for Heat Treatment
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• v.26 no.5
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• pp.233-240
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• 2013

Rapid and homogeneous heating in heat treatment has been a challenging engineering issue throughout a heating temperature over $1,000^{\circ}C$. Induction heating has been widely used in field of heat treatment compared with conventional heating system. Advantages in homogeneous heating, simple fabrication, and repeatable use can be efficiently made with the induction heater. In this paper, numerical analysis of an induction coil system for heat flux gauge heating is performed. The effect of configuration on the heating performance was considered in various cases of the coil radius, distance between the winding, relative height difference between the heat flux gauge and the coil, and the applied current frequency. Temperature distribution within the heat flux gauge at frequency-steady state was calculated with a finite element method. Sensitivity analysis was also performed and the relative importance of 2 key parameters; coil radius, distance between the winding, were taken as main contributors for induction heating.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.369-378
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• 2005

The maximum vehicle profile should be determined according to the required international standards as UIC505-1, BASS501 and other gauge. In this report, the method to determine the maximum vehicle construction gauge according to UIC505-1 has been studied and applied to the current designing vehicle.

• Proceedings of the KIEE Conference
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• 2002.11c
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• pp.224-227
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• 2002

In this paper, PIG(Pipeline Investigation Gauge) system is introduced and off-line navigation method for the system is studied. Off-line navigation is obtained by using a smoothing filter and the position of the point with some problems in gas pipeline can be detected with a good accuracy in real pipeline investigation experiment.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.47-48
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• 2006

A roughness measuring system which comprises an integrating sphere and a stabilized laser has been fabricated with the aim of measuring the roughness correction value which is necessary in gauge block measurement by optical interferometry. To calibrate the system, a Newton's ring interferometer has been introduced. The method how to calibrate the roughness measurement system has been described.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.1
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• pp.38-44
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• 1996

The CAD system for design and drawing of limit gauges was constructed and developed. This system was made by Visual Basic program. Using this system, drawings together with concerned data for the manufacturing of limit gauges are generated on the screen, file and printer. The data base was constructed by referring handbooks, textbooks, relevant standards and regulations. This system was proved a powerful tool for design and drawing of limit gauges by actual applications. The output drawings from this system are in good agreement with the drawings and data of the concerned standards and regulations.

• Bulletin of the Korean Mathematical Society
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• v.61 no.1
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• pp.93-115
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• 2024

In this paper, the Gauge-Uzawa methods for the Darcy-Brinkman equations driven by temperature and salt concentration (DBTC) are proposed. The first order backward difference formula is adopted to approximate the time derivative term, and the linear term is treated implicitly, the nonlinear terms are treated semi-implicit. In each time step, the coupling elliptic problems of velocity, temperature and salt concentration are solved, and then the pressure is solved. The unconditional stability and error estimations of the first order semi-discrete scheme are derived, at the same time, the unconditional stability of the first order fully discrete scheme is obtained. Some numerical experiments verify the theoretical prediction and show the effectiveness of the proposed methods.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.229-230
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• 2023

In this study, the hydration heat differential method was applied to mass concrete structures, and the hydration heat analysis was compared and analyzed with on-site measurement results. The results showed that the temperature history measurements of mass concrete were managed at a difference of 8.4 ℃, and although there was some deviation in thermal stress, a similar trend was observed. Consequently, it was determined that the thermal stress on the surface of mass concrete is less than its tensile strength, which would prevent the occurrence of thermal cracks.

• Magazine of the Korean Society of Agricultural Engineers
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• v.38 no.2
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• pp.108-122
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• 1996

This study was to introduced estimation model for optimum probabilistic rainfall intensity on hydrological area. Originally, probabilistic rainfall intensity formula have been characterized different coefficient of formula and model following watersheds. But recently in korea rainfall intensity formula does not use unionize applyment standard between administration and district. And mingle use planning formula with not assumption model. Following the number of year hydrological duration adjust areal index. But, with adjusting formula applyment was without systematic conduct. This study perceive the point as following : 1) Use method of excess probability of Iwai to calculate survey rainfall intensity value. 2) And, use method of least squares to calculate areal coefficient for a unit of 157 rain gauge station. And, use areal coefficient was introduced new probabilistic rainfall intensity formula for each rain gauge station. 3) And, use new probabilistic rainfall intensity formula to adjust a unit of fourteen duration-a unit of fifteen year probabilistic rainfall intensity. 4) The above survey value compared with adjustment value. And use three theory of error(absolute mean error, squares mean error, relative error ratio) to choice optimum probabilistic rainfall intensity formula for a unit of 157 rain gauge station.

• Journal of Drive and Control
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• v.20 no.1
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• pp.41-47
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• 2023

The aim of this study was to develop a method for installing strain gauges on moving, lubricating oil-filled, and sealed parts, such as drive shafts of equipment, including construction machinery. A measuring device was constructed using an embedded CPU and an IoT sensor to measure the strain of the strain gauge, which allowed for the measurement of axial torque and axial force, and subsequent analysis. To verify the performance of the developed device, the axial torque and axial force of the forklift were measured during operation using a strain gauge attached to the inside of the drive shaft. This study confirmed the possibility of measuring and analyzing the strain of a moving part, such as the inside of a drive shaft, which is sealed and filled with hydraulic oil.