• Journal of Mechanical Science and Technology
• /
• 제16권4호
• /
• pp.476-484
• /
• 2002

The aim of this study is to investigate the ductile fracture behavior under mixed mode (I/II) loading using SA533B pressure vessel steel. Anti-symmetric 4-point (AS4P) bending tests were performed to obtain the J-R curves under two different mixed mode (I/II) loadings. In addition, finite element analysis using Rousselier Ductile Damage Theory was carried out to predict the J-R curves under mixed mode (I/II) loadings. In conclusions, the J-R curves under. Mixed Mode (I/II) loading were located between those of Mode I and Mode II loading. When the mixity of mixed mode (I/II) loading was high, the J-R curve of mixed mode (I/II) loading approached that of pure mode I loading after some amount of crack propagation. In contrast with the above fact, if the mixity was low, the J-R curve took after that of pure mode II loading. Finally, it was found that the predicted J-R curves made a good agreement with the test data through the tuning procedures of $\beta$ values at the different mixed mode (I/II) loading.

• 한국압력기기공학회 논문집
• /
• 제16권2호
• /
• pp.35-46
• /
• 2020

In this paper, a fracture mechanics evaluation system which can be used to assess the leak-before-break (LBB) of nuclear piping is developed. Existing solutions for calculating the fracture mechanics parameters (J-integral and crack opening displacement) required for LBB evaluation were firstly presented. Then a module for calculating J-integral and COD was developed, with an additional module for predicting the critical load based on the crack driving force diagram to finally develop a fracture mechanics evaluation system. To confirm the validity of the proposed evaluation system, finite element (FE) analysis was performed, and the FE J-integral and COD results were compared with prediction results using the J-integral and COD estimations program. Furthermore, the critical load assessment module was verified by comparing the actual pipe test results (Battelle test data) with prediction results using the proposed program.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 하계학술대회 논문집 C
• /
• pp.1969-1971
• /
• 2004

For evaluation of partial discharge performances of electrical power appratus such as Insulator, circuit breaker and transformer and so on, Partial discharge measuring system(ERA) consisted of PD detector including amplifier, coupling capacitor, PD calibrator and voltage divider are used PD measuring system is very important factor which affect the test result and show reliability of test result in test laboratory, In this paper, we describe tracebility and uncertainty of PD measuring system in test laboratory based on IEC 60270.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2001년도 춘계학술대회논문집E
• /
• pp.668-671
• /
• 2001

For the saving of energy consumption, it is necessary that the high efficient energy transfer machine. We found the optimum operating condition of screw water chiller during this performance test. The specifications of compressor for this performance test are as follows. Built-in volume ratio; Vi=2.4, using refrigerant; HCFC-22, nominal motor output; 60kW(80Hp). We found the test results on water cooled chiller standard test condition that the evaporating capacity is increased 8% maximum and 5.6% under same operating condition. and COP is increased 11 % max. and 8% under same operating condition with change of the evaporating inlet/outlet condition. For the results of these test, we can estimate the optimum operating condition of water cooled type screw chiller.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(II)
• /
• pp.1476-1480
• /
• 1987

This paper proposes a design method for SCLA(sequential CMOS Domino Logic Array) using 1-level CMOS Domino Logic and Stable Shift Register Latch. Also an algorithm to generate a test sequence and a test procedure for the SCLA are presented. The SCLA has advantages of low power consumption, high density and high speed, and performs hazard-and race-free logic operation, because of using SSRL(Stable Shift Register Latch). By using the proposed test method, all of stuck-at, cross-point, stuck-on and stuck-open faults in SCLA are detected by short test sequence.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2008년도 제39회 하계학술대회
• /
• pp.241-242
• /
• 2008

Korea Electric Power Research Institute has being carried out an IEC 61580 communication service test on IED trial products developed related to power IT project, "The verification of Performance of the Substation Automation System and Its Field Test". This paper presents reporting services of IEC 61850-8-1 and related UCA Test procedures, reporting test items are widely divided into unbuffered report and buffered report and this paper is dealing with unbuffered report.

• 동력기계공학회지
• /
• 제9권1호
• /
• pp.64-69
• /
• 2005

In evaluation of electronic reliability on the PCB(Print Circuit Borad),electrochemical migration is one of main test objects. The phenomenon of electrochemical migration occurs in the environment of the hight humidity and the hight temperature under bias through a continuous aqueous electrolyte. In this paper, the generating mechanism of electrochemical migration is investigated by using water drop acceleration test under various waters. The waters used in the water drop test are city water, distilled water and ionic water. It found that the generated velocity of electrochemical migration depended on electrolyte quantity which included in the various waters.

• 재활복지공학회논문지
• /
• 제4권1호
• /
• pp.15-21
• /
• 2010

초음파자극기의 오동작이나 부작용에 대한 예방으로 안전성 확보와 품질 향상이 필요하며 이를 위한 시판전의 시험검사나 시판후의 수거검사시에 안전성 및 성능평가를 위한 표준시험방법 이 필요하다. 본 논문에서는 초음파자극기에 대한 전기적 안전성 평가를 위한 필수시험과 성능평가를 위한 표준시험방법을 연구하였다.

• Steel and Composite Structures
• /
• 제1권2호
• /
• pp.231-244
• /
• 2001

The strengthening of reinforced concrete structures using externally bonded steel or advanced fibre reinforced plastic (FRP) composites is becoming increasingly common. A key factor affecting the behaviour and reliability of such strengthened structures is the bond strength between the steel or FRP plate and the concrete substrate. Several different experimental set-ups have previously been used to determine bond strength. This paper presents a careful finite element analysis of the stress distributions in these test set-ups. Results show that stress distributions can be significantly different for different set-ups, for similar materials and geometry.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 하계학술대회 논문집 B
• /
• pp.1373-1375
• /
• 2004

This paper presents the design of DC protection Relay for Light Rail Transit system, which is very beginning product in domestic. Protection Function characteristic, principle and I/O interface including interlock signal has been introduced. The protection algorithm and EMC characteristics have been certified by official organization and Type test report has been introduced. Up to date in domestic, the test procedure for DC Protection relay hasn't been established so the new method and test equipment based on IEC regulations are proposed. Finally the product will be proved based on field test.