• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1261-1262
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• 2013

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.1029-1034
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• 2003

The basic Physical properties, Slump, Slump Flow, Air content, Bleeding, and Settlement of concrete was investigateed to test Characteristic of Setting and to evaluate the relation between Model Specimen and Heat of hydration for construction Over the High Temperature (CFT). The objective of this study is to take the partial core after the cementation of Model Specimen, test the compression intensity and analyze the relation to Test Piece.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1391-1393
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• 2008

In this paper, the long-term reliability for 1.25G transceiver in use of high speed optical access network is investigated. High temperature storage tests and accelerated life tests are used to long-term reliability. Accelerated aging test have been during 3,000 hour of the three accelerated aging conditions by caused high temperature stress. Mean life is assumed to follow the Arrhenius relationship and analysis from the failure data obtained in the accelerated aging conditions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.513-515
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• 1999

In this study, we evaluated the relation of the test and theory of low impedance cable As the result We could obtained the result in accordance the test with theory in 85 ~ 95% tolerance . Test method measured the relation of the current and temperature of cable jacket in using CT to put in 3 phase AC current simultationiously. The current and temperature of it was calculated in according to JCS- l68D

• Proceedings of the Safety Management and Science Conference
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• 2008.11a
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• pp.153-160
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• 2008

This paper presents the log likelihood function for integrated models for ALT such as exponential-general Eyring, Weibull-temperature and specific heat, lognormal-temperature and specific heat. Additionally this paper estimates the system reliability and mean time to failure(MTTF) for series, parallel, k of n, and standby system using ALT linkage parameter. Lastly this study designs three variable reliability acceptance sampling(RAS) plans such as type I, II censored test, sequential test by the use of integrated models for ALT.

• Proceedings of the KSR Conference
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• 1999.11a
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• pp.385-390
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• 1999

In this paper, we investigated the wear rate, braking temperature and stopping distance of the composite brake shoe for diesel locomotive in the field test. The wear rate and braking temperature of the composite brake shoe would rather than cast iron. Also, the stopping distance of composite brake shoe is 450m at 100km/h. This result of field test shown that the density distribution of the composite brake shoe influence on wear rate.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.1
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• pp.90-98
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• 2016

Currently government certified test method for an automobile remanufactured products is insufficient. Thus many automotive parts in the remanufacturing market are lacking proper evaluation criteria and production of defective products are causing customer dissatisfaction. In this paper a power steering oil pump, which requires stringent manufacturing standards, is studied by the failure mode and effect analysis approach. The research suggested that the test criteria such as discharge flow characteristic test, tightness test, pulley run-out test, pressure switch operation test, low temperature test and rotation pressure durability test should be performed to evaluate the reliability of remanufactured power steering oil pumps. As a result of tests, the performance of remanufactured power steering oil pump satisfied the evaluation criteria of pressure switch operation test and low temperature test. However, the remanufactured power steering oil pump failed to satisfy the evaluation criteria on discharge performance test, tightness test and pulley run-out test. These performance evaluation tests proved the necessity of standard process for the remanufactured power steering oil pump.

• Journal of Technologic Dentistry
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• v.31 no.2
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• pp.39-44
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• 2009

In the orthopedic field which firstly used zirconia as artificial joints, researchers had studied the reasons for collapsing zirconia used as restorative material by accumulated inner cracks in several years and they found out Low Temperature Degradation is one of the reasons. In the dentistry field, it has not been too long since they used zirconia as the cores of all-ceramic restoration; however, the study is needed as prophylactic measure against Low Temperature Degradation which can be caused by saliva wetting the mouth all the time and frictional forces such as bite pressure and masticatory pressure. Artificial aging by autoclaving is used because there are difficulties of testing in the patient's mouth. To study the changes in the material properties, the flexural strength of dental zirconia ceramic is measured before and after the test. The following are the result of the test. 1) The zirconia blocks in the autoclaves at $130^{\circ}C$ and $200^{\circ}C$ are phase-shifted tetragonal to monoclinic by Low Temperature Degradation. 2)The non-autoclaved specimens have the average fractural strength of 1346.4MPa, the specimens autoclaved at $130^{\circ}C$ have 1226.4Mpa and the specimens autoclaved at $200^{\circ}C$ have 1024.1MPa. The tests show that as the temperature increases, the flexural strength tend to decrease and the differences are noticeable(p<0.001). 3)Through the Duncan's post-hoc test, the differences in flexural strength of the 3 groups were listed in order of strength like normal temperature>at $130^{\circ}C$ autoclave low temperature degradation> at $200^{\circ}C$ autoclave low temperature degradation.

• The Journal of Korean Physical Therapy
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• v.15 no.4
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• pp.455-465
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• 2003

The purpose of this study was to describe the alteration of muscle action potential of spastic upper extremity in a patient with cerebral palsy by the water temperature. We used seven patients with cerebral palsy. Participants classified according to each group in $29^{\circ}C,\;35^{\circ}C$ by the water temperature. All subjects participated 2 session, which at least 1 week between session. The test was measured continuously pre test, post-test by thermometer and surface EMG. The following results were obtained; 1. In changes of surface temperature, wrist flexor and extensor were significantly decreased in $29^{\circ}C$ (p<0.001) group but were significantly increased $35^{\circ}C$ group(p<0.01). 2. In changes of surface temperature, wrist flexor and extensor were significantly differenced between $29^{\circ}C$ and $35^{\circ}C$ group(p<0.001). 3. In changes of muscle action potential, wrist extension antagonist were significantly increased in $29^{\circ}C$ group(p<0.05). 4. In changes of muscle action potential, wrist flexion agonist were more significantly increased in $29^{\circ}C$ group(p<0.01). 5. In changes of muscle action potential, wrist extension antagonist were significantly differenced between $29^{\circ}C$ and $35^{\circ}C$ group(p<0.05). These results lead us to the conclusion that changes of muscle action potential of spastic upper extremity in a patient with cerebral palsy were influenced by the water temperature. Therefore, a further direction of this study will be to provide more evidence that a moderate water temperature have an effect on muscle tone in a patient with cerebral palsy.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.33 no.12
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• pp.19-27
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• 2017

This paper is a study to improve the fire-resistance capacity of reinforced concrete (RC) members strengthened by fiber-reinforced-polymer (FRP). The fire resistance of the RC members strengthened by FRP was evaluated through high temperature exposure test. In order to improve the fire resistance of the FRP reinforcing method, a fire-proof board was attached to the reinforced FRP surface and then the high temperature exposure test was carried out to evaluate the improvement of the fire resistance performance. It was confirmed that the resistance to high temperature of NSMR could be improved somewhat compared with that of EBR from the experiment that exposed to high temperature under the load corresponding to 40% of nominal strength. When 30 mm thick fire-resistance (FR) board is attached to the FRP surface, the surface of the reinforced FRP does not reach $65^{\circ}C$, which is the glass transition temperature (GTT) of the epoxy until the external temperature reaches $480^{\circ}C$. In particular, when a high performance fire-proof mortar was first applied prior to FR board attachment, the FRP portion did not reach the epoxy glass transition temperature until the external temperature reached $600^{\circ}C$.