• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.349-354
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• 2001

The split Hopkinson pressure bar has been used for a high strain rate impact test. Also it has been developed and modified for compression, shear, tension, elevated temperature and subzero tests. In this paper, SHPB compression tests have been performed with pure titanium at elevated temperatures. The range of temperature is from room temperature to $1000^{\circ}C$ with interval of $200^{\circ}C$. To raise temperature of the specimen, a radiant heater which is composed of a pair of ellipsoidal cavities and halogen lamps is developed at high temperature SHPB test. There are some difficulties in a high temperature test such as temperature gradient, lubrication and prevention of oxidation of specimen. The temperature gradient of specimen is affected by the variation of temperature. Barreling occurred at not properly lubricated specimen. Stress-strain relations of pure titanium have been obtained in the range of strain rate at $1900/sec{\sim}2000/sec$ and temperature at $25^{\circ}C{\sim}1000^{\circ}C$.

• 시스템엔지니어링학술지
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• 제16권2호
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• pp.78-86
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• 2020

The environmental tests are one of the key branches of the reliability tests. The purpose of the high/low environmental test of KT-1 Export Version Trainer is not only based on meeting the compliance of the reliability, customer satisfaction, but also for the expansion of its export. Amongst many existing environmental tests, the high and low temperature tests are considered as the two most important tests. The tests are considered and tailored to the high and low temperature methods of MIL-STD-810H. This paper proposes the tailoring processes and the results of High/Low temperature conditions, test procedures, and test profiles for the aircraft. Additionally, this paper is described by considering the view of MIL-STD-810H.

• 시스템엔지니어링학술지
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• 제6권1호
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• pp.41-46
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• 2010

The ground high/low temperature test objective is to check the normal ground operation of FA-50 aircraft in the extreme ground ambient conditions. The aircraft was exposed in climatic conditions of the basic climatic category according to the MIL-HDBK-310. For verified normal operation in the extreme high temperature, the high temperature test was performed in the hot regional type conditions and accentuated solar radiation heat. This test was performed at the test chamber in ADD where is in Haemi. This paper was described about the test procedure of FA-50 high/low temperature including preparation, testing and results.

• 한국신뢰성학회지:신뢰성응용연구
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• 제2권1호
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• pp.1-14
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• 2002

High temperature operating test, temperature humidity test and temperature cycling were performed at various test levels for solid aluminum electrolyte capacitors made by domestic manufacturing company and foreign advanced manufacturing company. It was found that main failure mode of solid aluminum electrolyte capacitors was the decrease of their capacitances. The decrease of their capacitances has the same pattern in these tests. Test result for comparison of characteristics between domestic products and foreign advanced products shows that domestic products have the shorter lifetime and their capacitances decrease more rapidly in high temperature operating test and temperature humidity test. Also in these tests, accelerated tests for high temperature operating test and temperature humidity test were developed.

• 한국자동차공학회논문집
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• 제8권6호
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• pp.279-286
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• 2000

The stud bolts tend to degrade faster by high temperature(over 45$0^{\circ}C$). Therefore, replacement cycle inspection of stud bolts were carried out various method such as ultrasonic test(UT), magnetic test(MT), wobble test, visual test and hardness test. Especially, wobble test method has been applied to determine replacement evaluation criteria of stud bolt after long time operation. We applied three different methods on the three site and the obtained data are compared with the results from the evaluation methods. From the results, the replacement criteria for stud bolts under high temperature in power plants are proposed.

• 한국군사과학기술학회지
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• 제25권4호
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• pp.355-363
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• 2022

Development of supersonic flying vehicle is one of the most latest issue in modern military technology. Specifically, structural integrity of supersonic flying vehicle can be verified by high temperature structural test. High temperature structural test is required to consider thermal load caused by aerodynamic heating while applying structural load simultaneously. Tubular quartz lamps are generally used to generate thermal load by emitting infrared radiation. In this study, modified heat flux model of tubular quartz lamp is proposed based on existing model. Parameters of the proposed model are optimized upon measured heat flux in three dimensions. Finally, thermal load of plate specimen is designed by the heat flux model. In conclusion, it is possible to predict heat flux applied on plate specimen and desired thermal load of high temperature structural test can be obtained.

• 한국군사과학기술학회지
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• 제4권1호
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• pp.255-263
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• 2001

The main purpose of this paper is to investigate strength characteristics of Aluminum 2024-T3 in high temperature environment. Tensile test of Aluminum 2024-T3 has been carried out in high temperature environment. The stress-strain relations are investigated with temperature and Young's modulus, yield strength and ultimate strength are deduced from the test results. The modulus and strength of the test are compared with those of MIL HANDBOOK and tips on structural design in high temperature environment are suggested.

• 한국전기전자재료학회논문지
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• 제19권12호
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• pp.1123-1127
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• 2006

There are various elements that have influence on safety and reliability of high speed railway. Among them, mechanical characteristics of traction motors are very important. Therefore, we verified that temperature characteristics have influence on damage and durability of these parts. We designed a measurement system for temperature test, and could measure the temperature of each device by the system. As the result of temperature test, we could confirm that the traction motors on Korean High-Speed Train satisfy the criteria. From this test, we get information of the traction motor about the temperature characteristic during running speed and running time.

• 한국기계가공학회지
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• 제11권4호
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• pp.180-184
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• 2012

3-way ball valves have been mostly used for high temperature/high pressure valves using in petrochemical carriers and oil tankers, which requires high quality products with confidentiality and durability. As a larger disaster may be generated by leakage of oil or gas from valves, thus the present research applied a numerical analysis method with thermal-structural coupled field analysis and the performance test. The Max stress by parts was confirmed through thermal-structural coupled field analysis and develop the 3-way ball valve design, which is safe on operating condition. And its performance was verified by carrying out pressure test, leakage test and durability test for the manufactured 3-way ball valves with satisfying it's regulations.

• 대한기계학회논문집A
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• 제32권11호
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• pp.1028-1034
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• 2008

The exhaust systems are usually subjected to vibration or shock at high temperatures. The high temperature fatigue tests of the exhaust systems are rarely performed in domestic industries due to limited number of test facility and high test costs. In this paper, the high temperature fatigue test of some part of the exhaust system, not the whole system, is carried out. The resonator located at the central range is heated in the cylindrical electric furnace and the alternating load is applied on the end of the pipe welded to the resonator. The high temperature fatigue strength of the welded joint is obtained. The location of the fatigue crack is different to that in room temperature.