• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 1998년도 추계학술발표회요약집
• /
• pp.193-193
• /
• 1998

• 대한치과보존학회:학술대회논문집
• /
• 대한치과보존학회 2001년도 춘계학술대회
• /
• pp.259-259
• /
• 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

• 한국IT서비스학회지
• /
• 제17권4호
• /
• pp.75-83
• /
• 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.

• 국제학술발표논문집
• /
• The 6th International Conference on Construction Engineering and Project Management
• /
• pp.317-320
• /
• 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.

• 한국균학회지
• /
• 제45권2호
• /
• pp.132-138
• /
• 2017

작약에서 분리된 Cylindrocarpon destructans KACC44663 균주의 인삼에 대한 병원성 여부를 밝혀내고자 병원성 검정을 실시하였고 새로운 분류체계에 따른 균의 재분류를 위해 계통학적 유연관계를 분석하였다. 작약으로부터 분리된 KACC44663 균주가 인삼에 병을 일으키는 것을 확인하였고, 새로운 분류체계에 의해 I. radicicola species complex 내 위치하는 Ilyonectria robusta로 동정하였다. 이는 국내에서 타 기주로부터 분리된 병원균이 인삼에 뿌리썩음병을 일으키는 것을 증명한 첫 사례이다.

• 한국안전학회지
• /
• 제35권5호
• /
• pp.115-120
• /
• 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
• /
• 제7권1호
• /
• pp.125-128
• /
• 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.

• 대한안전경영과학회지
• /
• 제15권1호
• /
• pp.101-108
• /
• 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.

• 수산해양교육연구
• /
• 제25권3호
• /
• pp.716-723
• /
• 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.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2005년도 춘계학술대회논문집
• /
• pp.794-799
• /
• 2005

The failure of blades frequently happened in the 300MW LP turbine until now and they are maintaining the blades periodically during outage. So the blade-disk system is analysed by FEM in order to identify the main cause of failure of blade row. It is found that the stress of root's hole is highest in comparison with other parts from the result of the steady stress analysis. Also, the two dangerous frequencies which is related to the resonance condition are found in the interference diagram. one is 1,516 Hz which is related to the operating speed. The other is 2,981 Hz which is related to the 1 nozzle passing frequency. The dynamic stress analysis is per-formed to identify more accurate root cause for failure of blade row. It is confirmed that the dynamic stress of the latter is higher than one of the former. From these results, it is concluded that the former has deeply something to do with the failure of blades more than the latter. Based on versatile investigation and deliberation, the change of blade's grouping is determined to avoid the resonance condition with the operating speed. After the blade grouping is changed, the former frequency vanish completely but the latter is still in existence in the interference diagram. Fortunately, It is confirmed that the dynamic stress of the new blade grouping is lower than one of the old blade grouping. 2 years has passed since modification and the LP turbine is operated well without failure so far.