• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.7 no.3
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• pp.61-66
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• 2011

The integrity of the SG(Steam Generator) tubes has been challenged by numerous factors such as flaws, operation, atmosphere, inherently degraded materials, loose parts and even human errors. Of the factors, loose parts(or foreign materials) on the secondary side of the tubes can bring about volumetric defects and even leakage from the primary to the secondary side in a short period of time. More serious concerns about the loose parts are their unknown influx path and rapid growth rate of the defects affected by the loose parts. Therefore it is imperative to detect and characterize the foreign materials and the defects. As a part of the measures for loose part detection, TTS(Top of Tubesheet) MRPC(Motorized Rotating Pancake Coils) ECT has been carried out especially to the restricted high probability area of the loose part. However, in the presence of loose parts in the other areas, wide range loose part detection techniques are required. In this study, loose part standard tube was presented as a way to accurately detect and characterize loose part signals. And the SG tube ECT bobbin coil and MRPC ISI(In-service Inspection) data of domestic OPR-1000 and Westinghouse Model F(W_F) were reviewed and consequently, comprehensive loose part detection technique is derived especially by applying bobbin coil signals

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.3
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• pp.43-49
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• 2008

The objective of this research was to test a hypothesis that sprawl increases congestion, and so the estimated evacuation time become longer. For this, sprawl was thought to be poor accessibility so that vehicle miles of travel become longer. This research shows that the daily vehicle miles per lane mile that are thought to be an accessibility index had a strong and statistically significant relationship to the estimated evacuation time, while urban population density has no statistically significant relationship to the evacuation time. The result of this research recommends that we should consider sustainable land use patterns that decrease traffic demand by providing good accessibility.

• Journal of Climate Change Research
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• v.5 no.2
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• pp.179-187
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• 2014

The global warming caused by GHG has emerged as a global environmental problem. For this reason the continued efforts to reduce GHG emission by international cooperation and each country are in progress. This study was performed for a successful accomplishment of Korea's ETS aims in 2015, that is to reduce GHG emission, maintain competitiveness of the domestic industries and to reinforce competitiveness of the environmental management of domestic companies through comparing analysis research of major overseas ETSs with main features of Korea's ETS and the analysis of semiconductor industry. In this study, the cases of already being implemented ETS countries such as the European Union, the United States and New Zealand etc. have been investigated by comparing to Korea's ETS. We also suggested the detailed political proposals to stabilize the introduction of Korea's ETS at the enterprise level.

• Journal of Korean Neurosurgical Society
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• v.67 no.2
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• pp.237-248
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• 2024

Objective : Postoperative data on Cushing's disease (CD) are equivocal in the literature. These discrepancies may be attributed to different series with different criteria for remission and variable follow-up durations. Additional data from experienced centers may address these discrepancies. In this study, we present the results obtained from 96 endoscopic transsphenoidal surgeries (ETSSs) for CD conducted in a well-experienced center. Methods : Pre- and postoperative data of 96 ETSS in 87 patients with CD were included. All cases were handled by the same neurosurgical team between 2014 and 2022. We obtained data on remission status 3-6 months postoperatively (medium-term) and during the latest follow-up (long-term). Additionally, magnetic resonance imaging (MRI) and pathology results were obtained for each case. Results : The mean follow-up duration was 39.5±3.2 months. Medium and long-term remission rates were 77% and 82%, respectively. When only first-time operations were considered, the medium- and long-term remission rates were 78% and 82%, respectively. The recurrence rate in this series was 2.5%. Patients who showed remission between 3-6 months had higher long-term remission rates than did those without initial remission. Tumors >2 cm and extended tumor invasion of the cavernous sinus (Knosp 4) were associated with lower postoperative remission rates. Conclusion : Adenoma size and the presence/absence of cavernous sinus invasion on preopera-tive MRI may predict long-term postoperative remission. A tumor size of 2 cm may be a supporting criterion for predicting remission in Knosp 4 tumors. Further studies with larger patient populations are necessary to support this finding.