• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2012.10a
• /
• pp.745-746
• /
• 2012

• The Journal of Information Technology
• /
• v.10 no.3
• /
• pp.77-92
• /
• 2007

This study aims to suggest an implementation methodology of security module for data integrity of mobile internet terminal. This is based on the WTLS(Wileless Transport Layer Security) of WAP Protocol. This security module is expected to achieve central role in conversion of wireless internet environment and emphasis of encryption technology and safe and calculable wireless communication environment construction.

• Journal of the Korean Institute of Gas
• /
• v.5 no.4 s.16
• /
• pp.21-26
• /
• 2001

Because of the continuous growth of energy consumption, and also tile tendency to site power lines and pipelines along the same routes, the close proximity of high voltage structures and metallic pipelines has become more and more frequent. Recently, the results of assessment about a system integrity are needed in korea also when a gas pipeline is running parallel with high voltage power line in same submarine tunnel, Therefore, we analyze the system integrity(AC corrosion of pipe, melting of pipeline coating, safety of insulation flange, especially cathodic protection system which are rectifier and CI(cathodic Isolator)) resulting from the influence of high voltage power system.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.24 no.4
• /
• pp.331-340
• /
• 2004

Deployment of an advanced on-line monitoring of the component integrity offers a prospect of improved performance, enhanced safety, and reduced overall cost for nuclear power plants. Ultrasonic guided waves have been known as one of the promising techniques that could be utilized for on-line monitoring. The present work is aimed at developing a new method for on-line monitoring of the pipes during the operation period of nuclear power plants. For this purpose, the steam generator (S/G) tube was selected as an object of tile experiment. Dispersion corves and the incident angles corresponding to the specific modes were calculated for the S/G tube. The modes of guided waves were identified by the time-frequency diagrams obtained by the short time Fourier transform. It was experimentally confirmed that there was no mode conversion when the ultrasonic guided waves passed over the curved region of the S/G tube. An optimum mode of guided wave for the S/G tube was suggested and verified by the experiment.

• Proceedings of the Korean Nuclear Society Conference
• /
• 2005.10a
• /
• pp.953-954
• /
• 2005

• Proceedings of the KWS Conference
• /
• 2005.06a
• /
• pp.144-146
• /
• 2005

Measurements of Thermoelectric power (TEP) were used to evaluate microstructural analysis in HSLA steel weldments. The measurements of TEP for weld microstructure across weldment have shown good correlation with hardness profile. The different TEP values indicated that changes in weld microstructure can be correlated with TEP values measured.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.12 no.3
• /
• pp.320-330
• /
• 2012

In this paper, we investigate the power integrity of grid structures for power and ground distribution on printed circuit board (PCB). We propose the 2D transmission line method (TLM)-based model for efficient frequency-dependent impedance characterization and PCB-package-integrated circuit (IC) co-simulation. The model includes an equivalent circuit model of fringing capacitance and probing ports. The accuracy of the proposed grid model is verified with test structure measurements and 3D electromagnetic (EM) simulations. If the grid structures replace the plane structures in PCBs, they should provide effective shielding of the electromagnetic interference in mobile systems. An analytical model to predict the shielding effectiveness (SE) of the grid structures is proposed and verified with EM simulations.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.62 no.7
• /
• pp.987-993
• /
• 2013

Integrity of the control and instrumental cables in nuclear power plant is important to maintain the stability of the nuclear power plants. In order to diagnose the integrity of the cables, the diagnostic methods based on reflectometry have been studied. The reflectometry is a non-destructive method and it is applicable to diagnose the live cables. We introduce a Gaussian enveloped linear chirp reflectometry to diagnose the cables in the nuclear power plants. In this paper, we estimate the instantaneous frequency of the Gaussian enveloped linear chirp signal by using the weighted robust least squares filtering to localize the impedance discontinuities in the class 1E instrumental cable.

• Journal of the Korean Society of Safety
• /
• v.21 no.6 s.78
• /
• pp.20-25
• /
• 2006

In the design of class 1 components to apply ASME code section III NB, a fatigue is considered as one of the important failure mechanisms. Fatigue analysis procedure and standard fatigue design curve(S-N curve) is suggested in ASME code, which had to be performed to meet the integrity of components at the design step. As the plant life extension for operating power plants and the long-lived plant design, however, are being progressed, the fact which the existing ASME fatigue design curve can not consider fatigue effects sufficiently comes to the fore. To find the technical solution for these problems, a number of researches and discussion are continued up to now. In this study, the detailed fatigue analyses using the 3 dimensional modeling for the fatigue-weakened components were performed to develop the optimized fatigue analysis procedure and their results are compared with other reference solutions.

• Journal of Mechanical Science and Technology
• /
• v.15 no.1
• /
• pp.10-20
• /
• 2001

The leak before break(LBB) concept is difficult to apply to a structure with a thin tube that is immersed in a water environment. A heat exchanger in a nuclear power plant is such a structure. The present paper addresses an application of the LBB concept to a heat exchanger in a nuclear power plant. The minimum leaked coolant amount(approximately 37.9 liters) containing the radioactive material which can activate the radiation detector device installed in near the heat exchanger is assumed. A postulated initial flaw size that can not grow to a critical flaw size within the time period to activate the radiation detector is justified. In this case, the radiation detector can activate the warning signal caused by coolant leakage from initially postulated flaws of the heat exchanger. The nuclear plant can safely shutdown when this occurs. Since the postulated initial flaw size can not grow to the critical flaw size, the structural integrity of the heat exchanger is not impeded. Particularly the informational scenario presented in this paper discusses an actual nuclear plant.