• Journal of Welding and Joining
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• v.33 no.1
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• pp.30-34
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• 2015

Residual stresses are inherently introduced into the engineering components during manufacturing including rolling, forging, bending and welding processes. Excessive residual stresses are known to be detrimental to the proper integrity and performance of components. Neutron diffraction has become a well-established technique for the determination of residual stresses in welds. The deep penetration capability of neutrons into most metallic materials makes neutron diffraction a powerful tool for the residual stress measurements through the thickness of the weld specimen. Furthermore, the unique volume-averaged bulk characteristic of the scattering beam and mapping capability in three dimensions is suitable for the engineering purpose. In this presentation, the neutron diffraction measurements of the residual stresses will be introduced and measurement results will highlighted in thick weld plates.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.15 no.2
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• pp.9-18
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• 2019

The objective of this study is to investigate the feasibility of simulating the mechanical properties of irradiatied austenitic stainless steels by cold-working. In this study, the tensile properties, cyclic hardening behaviors and fracture toughness of cold-worked TP316L stainless steel were compared with those of austenitic stainless steels irradiated by neutrons. It showed that cold-working can properly simulate the increase in strength and the decrease in ductility and fracture resistance of austenitic stainless steels by neutron irradiation, even though it could not perfectly simulate the microstructures of irradiated austenitic stainless steels. Also, cold-working can appropriately simulate the hardening behaviors of neutron irradiated austenitic stainless steels under monotonic and cyclic loading conditions.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.344-349
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• 2005

Neutron count rate measurements to assay fissile content of uranium powder have been carried out in a neutron counter. The induced fission neutrons by Cf-252 neutron source are counted as the variation of fissile material in fuel material. The measured counts are compared with equivalent results obtained from calculation. It shows that the measured neutron counts versus quantity of $UO_2$ powder enrichment agreed reasonably well with the calculated values.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05b
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• pp.154-158
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• 2003

In this study, to measure the density of compaction, it is designed to use the 5 gamma-ray detectors. The developed instrument consists of measuring circuits for gamma-rays and thermal neutrons, a high voltage supply unit, stable circuit unit, count circuit unit and a microprocessor. To read count pulse from gamma-ray detectors are very accurate and it can be count to data calibration excluded count of ripple.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2005.05a
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• pp.63-66
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• 2005

A soft error rate neutrons is a growing problem for integrated circuits with technology scaling. In the acceleration test with high-density neutron beam, a latch-up prohibits accurate estimations of the soft error rate (SER). This paper presents results of analysis for the latch-up characteristics in the circumstance corresponding to the acceleration SER test for SRAM. Simulation results, using a two-dimensional device simulator, show that the deep p-well structure has better latch-up Immunity compared to normal twin and triple well structures. In addition, it is more effective to minimize the distance to ground power compared with controlling a path to the $V_{DD}$ power.

• Proceedings of the KIEE Conference
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• 2007.10a
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• pp.253-254
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• 2007

This paper deals with the development of power control system(PCS) for nuclear power plants. The PCS provides the control motive power to operate the CEDMs(Control Element Drive Mechanism) for reactivity control inside the reactor vessel. The CEDM is raise and lower the CEAs( Control Element Assemblies) inside the reactor core. The CEAs are constructed with the Boron-10 isotope which has a high microscopic cross section of absorption for thermal neutrons. This characteristic causes the addition of negative reactivity when a CEA is inserted and positive reactivity when it is withdrawn from the reactor core.

• Nuclear Engineering and Technology
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• v.52 no.10
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• pp.2306-2312
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• 2020

Here we report on the first results of sensitivity evaluation of the gadolinium-aluminum-gallium- garnet (GAGG) scintillation detector with SiPM readout to fast and slow neutrons and, to the natural background and Co-60 γ-radiation as well. Data on sensitivity were obtained using certified dosimetry benches, so it can be utilized in the calculation of detection limits of neutron flux with such type of detectors. It was concluded that use of GAGG scintillator has a good prospect for neutron monitoring in different parts of nuclear research reactors and power plants.

• 전기의세계
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• v.29 no.2
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• pp.118-128
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• 1980

The properties of plasmas produced by high power glass laser were investigated with various methods of diagnostics. Electron temperature was estimated by measurement of soft X-ray, and ion temperature was estimated by measurement of the time-of-flight of ion. The measurement of incident and reflected laser light, and Schlieren and shadowgragh methods were also used. No influence of laser pulse duration on the temperature was observed in the case of durations 2, 4 and 10 nsecs. The effective heating of plasma occurred in about 2 nsec of beginning of incident laser pulse. The experimental results for fast rising laser pulse were discussed and the influence of resetime of laser pulse on the heating of plasma was described. Neutrons produced by irradiating laser beam to solid deuterium target were detected.

• Proceedings of the KAIS Fall Conference
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• 2004.11a
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• pp.203-205
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• 2004

A soft error rate neutrons is a growing problem for terrestrial integrated circuits with technology scaling. In the acceleration test with high-density neutron beam, a latch-up prohibits accurate estimations of the soft error rate (SER). This paper presents results of analysis for the latch-up characteristics in the circumstance corresponding to the acceleration SER test for SRAM. Simulation results, using a two-dimensional device simulator, show that the deep p-well structure has better latch-up immunity compared to normal twin and triple well structures. In addition, it is more effective to minimize the distance to ground power compared with controlling a path to the $V_{DD}$ power.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1626-1627
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• 2007

This paper deals with the design and manufacturing of power cabinet for reactor power control system(PCS). The PCS provides the control signals and motive power to operate the CEDMs(Control Element Drive Mechanism). The CEDM is raise and lower the CEAs(Control Element Assemblies) in the reactor core. The CEAs are constructed with the Boron-10 isotope which has a high microscopic cross section of absorption for thermal neutrons. This characteristic causes the addition of negative reactivity when a CEA is inserted and positive reactivity when it is withdrawn from the reactor core.