• Journal of the Korean Institute of Gas
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• v.17 no.3
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• pp.20-26
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• 2013

In this research, an empirical study on the designed burst pressure of Type3 composite cylinder was performed by hydrostatic burst test equipment. The designed burst pressure of Type3 composite cylinders, which are 6.8 liter and 31 MPa of service pressure, was estimated with the analysis using the finite element method. In order to confirm its accuracy, the burst test of small Type3 composite cylinders was perfomed through three times. The burst test equipment can pressurize to 400 MPa. As a result of comparison between the designed burst pressure and actual burst pressure, the difference was less than 4 percentage. With a test result, the analysis accuracy was verified. This technique will be applied to both qualification and inspection for the composite cylinder.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.111.1-111.1
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• 2012

We examine the relationship between a type II radio burst that started from an unusually high frequency of 425 MHz (fundamental component) and an associated white-light coronal mass ejection on 2011 February 13. The radio burst had a drift rate of 2.5 MHz/sec, indicating a relatively high shock speed. From SDO AIA observations we find that a loop-like erupting front sweeps across high density coronal loops near the start time of the burst (17:34:15 UT). We find fragmented structures of the type II burst, which indicates the signature of the shock propagating through the multiple loops. The deduced distance of shock formation (0.06 Rs) from flare center and speed of the shock (1100 km $s^{-1}$) using the measured density from AIA/SDO observations are comparable to the height (0.05 Rs, from the solar surface) and speed (700 km $s^{-1}$) of the CME leading edge observed by STEREO/EUVI. We conclude that the type II burst could be onset even in the low corona (41 Mm or 0.06 Rs, above the solar surface) if a fast CME shock passes through the high density loops.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.806-809
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• 1988

The frequency response characteristics of a bimorph type PZT piezoelectric transducer was investigated. In this study, function generator which generates short burst signal, plane reflection plate and oscilloscope were used to measure the characteristics of piezoceramic ultrasonic transducer. The resonant frequency of a bimorph type piezoceramic transducer which is acquired by using Tone-Burst Method had good agreement with the measured results from spectrum analyzer.

• Journal of the Chungcheong Mathematical Society
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• v.22 no.3
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• pp.367-374
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• 2009

The errors take place in the communication channel but they are often burst-error types. From properties of the Fi-bonacci code, it is not difficult to detect the burst-errors accompanying with this code. Fibonacci codes for correcting the double-burst-error patterns are presented. Given the channel length with the double-burst-error type, Fibonacci code correcting these errors is constructed by a simple formula.

• Journal of the Korean Society of Safety
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• v.30 no.4
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• pp.168-173
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• 2015

A steam generator tubing is one of the main pressure boundary of the reactor coolant system in the nuclear power plants. Structural integrity refers to maintaining adequate margins against failure of the tubing. Burst pressure of a tube at tube support plate can be higher than that for a free-span tube because failure behaviors could be interfered from the tube support plate. Alternative repair criteria for out-diameter stress corrosion cracking indications in tubes to the drilled type tube support plate were developed, however, there are very limited information to the eggcrate type tube support plate. This paper discussed reinforcement effect of steam generator tube burst pressure with axial out-diameter stress corrosion cracking within an eggcrate type tube support plate. A series of tube burst tests were performed under the room temperature and it was found out that there is no significant but marginal effects.

• Journal of the Korean Society of Safety
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• v.20 no.2 s.70
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• pp.38-43
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• 2005

Several nuclear power plants reported that they often found the combination cracks, which consist of longitudinal and circumferential cracks in the tubes. For the burst pressure of a tube with a single longitudinal or circumferential crack several experimental equations have been proposed in published literatures. But for the combination crack appropriate fracture criterion has not been proposed yet. In this study the burst pressures of a tube with a longitudinal crack or a T-type combination crack consisting of longitudinal and circumferential cracks were obtained experimentally and analytically. Fracture parameters such as crack opening angle (COA) were investigated by using elastic plastic analysis. Also the burst pressure far a T-type combination crack located near a tubesheet was considered to develop a length-based criterion. Because most of the axial, circumferential or combination cracks initiate in roll transition zone near the tubesheet.

• The Transactions of the Korea Information Processing Society
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• v.7 no.6
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• pp.1923-1931
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• 2000

In this paper, e analyze the performance of the PSS-type Viterbi decoder which can reduce calculations and power consumption using the Monte Carlo simulations. Gaussian and burst noise channels are considered in this simulation, and we achieve that convolutional interleaver can reduce complexity and power consumption in burst noise channel. In order to implement the high-speed PSS-type Viterbi decoder, the architectures of decoder are presented, and we implemented the PSS-type Viterbi decoder for r=1/2, k=3 using the VHDL tool, and prove the decoding process.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.2
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• pp.141-152
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• 2011

In this study, we extracted effective factors of pipe burst from the status data of water asset, operating data of pressure, volume and etc. and 7 years' pipe burst and repair records. The extracted factors were sorted by each attribution and then a statistical analysis was performed to generate a pipe burst probability function using the logistic regression model. As the result, material, diameter, length, laying year, pressure and road width affected to pipe burst significantly. Especially, in case of small diameter, laying year was most effective factor and in case of steel pipe, external loading was main cause of burst, and in case of cast iron, PE, PC, HP pipes, the deterioration of joint was main cause. The other side, as a result of Hosmer-Lemeshow goodness of fit test the models are turned out significant statistically. Also the classification criteria were determined to minimize the total cost from classification errors, when the predicted probability was more than 18% this pipe could have a chance of burst.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.2
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• pp.158-164
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• 2004

Steam generator tubes experience widespread degradations such as stress corrosion cracking, wear, tube rupture, denting, fatigue and so on. The resulting damages can cause tube bursting or leak of the primary water which contains radioactivity Therefore the allowable size of the damage is required to be determined on the maintenance purpose. The burst pressure of a tube with a T-type combination crack consisting of longitudinal and circumferential cracks is obtained experimentally and analytically. Fracture parameters such as stress intensity factor and crack opening angle are investigated. Also the burst pressure for a T-type combination crack is compared with that of a single longitudinal crack to develop a length-based criteria.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.365-368
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• 1995

Rotary Compressor has many AE(Acoustic Emission) sources according to condition of parts because it is operated with combination of various parts. In this study, analysis of AE raw signal generated form Rotary compressor which artificially-made parts inflicted abnormal condition was carried out. AE raw signals were acquired form high-speed A/D board, and many burst type signals were observed. By analyzing burst type signals which is caused form internal AE source,efficient AE parameters for monitoring and diagnosis were presented.