• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.180-181
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• 2004

• Proceedings of the Korean Nuclear Society Conference
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• 1998.10a
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• pp.193-193
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• 1998

• Proceedings of the KACD Conference
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• 2001.05a
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• pp.259-259
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• 2001

;A new root canal instrument and instrumentation technique: a preliminary report. Cleaning and shaping the root canal system has been and continues to be a challenge for even the most experienced endodontist. Curved. narrow canals. in particular. cause difficulties for the beginner as well as the specialist. A new instrument designed to incorporate new concepts was developed to ameliorate the problems in cleaning and shaping root canal systems. This new instrument has been given the name of SW (Senia and Wildey). The new SW instrument uses controlled right and left rotational forces. This motion was used to clean and shape simulated root canals in plastic blocks and root canals in extracted teeth. Instrumentation appeared to be easier. faster. and more precise than with conventional instruments. especially in curved canals where there was remarkable reduction of canal transportation. A mechanical version of the SW instrument was also developed. It was used to flare the coronal portion of the root canal system. Wildey WL. Senia ES., Oral Surg Oral Med Oral Pathol1989 Feb:67(2):198-207 Another look at root canal instrumentation. Several aspects of root canal instrumentation need additional research. Various factors must be considered in an analysis of instrumentation of the root canal system: the dentin that is cut: the technique used to cut it: the design of the instruments: the material and manufacturing process used to make the instruments: the irrigant used during the procedure: and the anatomic configuration of the root canal system. An analysis of these factors clearly indicates that existing root canal instruments and techniques are less than ideal and. in fact. do not accomplish what is expected of them. Root canals must be properly. but. at the same time. destructive and unnecessary removal of dentin should be kept to a minimum. The Flex-R and Canal Master instruments were developed to address some of the shortcomings of existing instruments and techniques. More scientifically based research is needed to fully evaluate these new instruments and techniques and to develop future instruments. Wildey WL; Senia ES. Montgomery S., Oral Surg Oral Med Oral Pathol1992 Oct:74(4):499-50799-507

• Journal of Information Technology Services
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• v.17 no.4
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• pp.75-83
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• 2018

Enterprises need to monitor systems for reliable IT service operations to quickly detect and respond to events affecting the service, thereby preventing failures. Events in non-critical systems can be seen as a precursor to critical system incidents. Therefore, event relationship analysis in the operation of IT services can proactively recognize and prevent faults by identifying non-critical events and their relationships with incidents. This study used the Recurrent Neural Network and Long Short Term Memory techniques to create a model to analyze event relationships in a system and to verify which models are suitable for analyzing event relationships. Verification has shown that both models are capable of analyzing event relationships and that RNN models are more suitable than LSTM models. Based on the pattern of events occurring, this model is expected to support the prediction of the next occurrence of events and help identify the root cause of incidents to help prevent failures and improve the quality of IT services.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.317-320
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• 2015

Documenting work-in-progress on construction sites using images captured with smartphones, point-and-shoot cameras, and Unmanned Aerial Vehicles (UAVs) has gained significant popularity among practitioners. The spatial and temporal density of these large-scale site image collections and the availability of 4D Building Information Models (BIM) provide a unique opportunity to develop BIM-driven visual analytics that can quickly and easily detect and visualize construction progress deviations. Building on these emerging sources of information this paper presents a pipeline for model-driven visual analytics of construction progress. It particularly focuses on the following key steps: 1) capturing, transferring, and storing images; 2) BIM-driven analytics to identify performance deviations, and 3) visualizations that enable root-cause assessments on performance deviations. The information requirements, and the challenges and opportunities for improvements in data collection, plan preparations, progress deviation analysis particularly under limited visibility, and transforming identified deviations into performance metrics to enable root-cause assessments are discussed using several real world case studies.

• The Korean Journal of Mycology
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• v.45 no.2
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• pp.132-138
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• 2017

To obtain useful data on root rot in Korean ginseng, we performed phylogenetic analysis and pathogenicity test for Cylindrocarpon destructans isolated from peony. Cylindrocarpon destructans isolates from peony were proven to cause ginseng root rot. The isolate KACC44663 was identified as Ilyonectria robusta under the new classification system, which belongs to the I. radicicola species complex. This is the first report of the pathogenic isolate, which was isolated from another host plant, but not ginseng, that can cause root rot disease on ginseng in Korea.

• Journal of the Korean Society of Safety
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• v.35 no.5
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• pp.115-120
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• 2020

From 2009 when the CNS facility was installed, the number of reactor failures due to abnormal CNS facility system has increased significantly. Of the total of 19 nuclear reactor shutdowns over the six years from 2009 to 2019, there were 10 nuclear reactor shutdowns associated with the CNS facility, which are very numerous. Therefore, this report intends to analyze the history of nuclear reactor shutdowns due to CNS facility system failure in detail, and to present the root cause and solution to problems. As a result of FMEA implementation of CNS facility system, a total of 76 SPVs were selected. In addition, 10 cases of reactor shutdown history due to CNS facility system abnormalities were analyzed in detailed, and improvement plans for solving the root cause and problem were suggested for each trip history. The results of this study are expected to be able to operate the domestic research reactor and CNS facilities more stably by providing effective measures to prevent recurrence of CNS facilities and reactor trips.

• KEPCO Journal on Electric Power and Energy
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• v.7 no.1
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• pp.125-128
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• 2021

This paper presents the root cause failure analysis of the circulating water pump in the 560 MW thermal power plant. A fractured austenitic stainless-steel shaft operated for 24 years was examined. Fracture morphology was investigated by micro and macro-fractographic analysis. The metallurgical analyses including chemical analysis, metallography and hardness testing were performed. The analysis reveals that the pump shaft was fractured due to the reverse bending load with combination of rotating bending load. Corrective actions for plant operator was recommended based on the analysis.

• Journal of the Korea Safety Management & Science
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• v.15 no.1
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• pp.101-108
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• 2013

Industrial disaster caused the deaths of 2,114, construction workers among them was the highest of 621 deaths. In the construction industry, has established a number of safety alternatives to prevent accidents. But until now, the cause of the accident has stopped being superficial analysis, awareness on the root cause of the acciden did not reflect. In this study, we analyze the characteristics and causes in G contractors' safety accidents. And innovation strategy, organization-wide safety management system and detailed tasks to derive essentially was to prevent the occurrence of large construction companies. A lot of business for accident prevention effect was transient and formal, to reflect a management style and organizational culture, and try to prevent construction accidents. we will strive to prevent the disaster from the construction site through the improvement of these.

• Journal of Fisheries and Marine Sciences Education
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• v.25 no.3
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• pp.716-723
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• 2013

The postal or group questionnaire survey was conducted to inquire into the cause of collision between fishing vessel and non-fishing vessel targeting fishing vessel personnel(FVP), non-NFVP and a person involved in a marine accident. As a result, we could verify the root cause of collision, a negligence of lookout which noted overwork for FVP and careless for non-FVP. The cause of collision by inappropriate avoid action was poor communications for FVP and non-FVP. To reduce collision, we need to be trained to take a sharp lookout, a radio communication by VHF and the collision avoidance actions by early and substantial action to keep well clear. The results are expected to contribute for the reduction of collision and victims.