• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.756-759
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• 2003

Steam Generator is one of the most important structural part of nuclear power plant. It is manufactured by welding process of various steel forgings such as shell, head, torus and tube sheet. These steel forgings have been made by open die forging process. After steel melting and ingot making, open die forging has been carried out to get a good quality which means high soundness and homogeniety of the steel forgings by using high capacity hydraulic press. This paper introduced open die forging status and investigated forging method of the ultra large steel forgings which is used for the steam generator of 1000MW nuclear power plant. For the same thing. the type of steel forgings consisting steam generator is classified by shell, head, torus and tube sheet. And corresponding forging processes of the steel forgings have been investigated.

• Journal of Electrical Engineering and Technology
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• v.9 no.1
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• pp.268-272
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• 2014

This letter presents a measurement methodology of the complex permittivity of liquid using a partially open cavity in narrow band. The partially open cavity (POC) can measure dielectric small changes caused by the temperature variation of the liquid inside the cavity as well. Using the resonance frequency and unloaded quality factor of the proposed POC, the complex permittivity is evaluated. The apertures on the walls of the cavity are designed to circulate the liquid inside to outside of the POC and located at the corner area of the cavity to minimize the disturbance of field distribution at the dominant mode. The results measured by the proposed POC were compared with those by the conventional open-ended probe and Cole-Cole equation. The POC showed better performance in measuring small dielectric constant changes than the open-ended probe.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.10a
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• pp.333-337
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• 2004

Steam Generator is one of the most important structural part of nuclear power plant. It is manufactured by various steel forgings such as shell, head, torus and tubesheet. These steel forgings have been made by open die forging process. After steel melting and ingot making, open die forging has been carried out to get a good quality which means high soundness and homogeniety of the steel forgings by using high capacity hydraulic press. This paper introduced the open die forging process and manufacturing experience of large tubesheet forgings which will be used for the steam generator of 1,400MW nuclear power plant.

• International Journal of Fluid Machinery and Systems
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• v.4 no.1
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• pp.161-171
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• 2011

The availability of a high quality open source CFD simulation platform like OpenFOAM offers new R&D opportunities by providing direct access to models and solver implementation details. Efforts have been made by Hydro-Qu$\'{e}$bec to adapt OpenFOAM to hydroturbines for the development of steady-state capabilities. This paper describes the developments that have been made to implement new turbomachinery related capabilities: multiple frames of reference solver, domain coupling interfaces (GGI, cyclicGGI and mixing plane) and specialized boundary conditions. Practical use of the new turbomachinery capabilities are demonstrated for the analysis of a 195-MW Francis turbine.

• Transactions of Materials Processing
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• v.14 no.6 s.78
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• pp.565-569
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• 2005

Reactor Vessel is one of the most important structural parts of nuclear power plant. It is manufactured by various steel forgings such as shell, head and transition ring. Head forgings have been made by open die forging process. After steel melting and ingot making, open die forging has been carried out to get a good quality which means high soundness and homogeniety of the steel forgings by using high capacity hydraulic press. This paper introduced the open die forging process and manufacturing experience of large head forgings which can be used for the reactor vessel of 1,000MW nuclear power plant.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.05a
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• pp.397-400
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• 2005

Reactor Vessel is one of the most important structural part of nuclear power plant. It is manufactured by various steel forgings such as shell, head and transition ring. Head forgings has been made by open die forging process. After steel melting and ingot making, open die forging has been carried out to get a good quality which means high soundness and homogeniety of the steel forgings by using high capacity hydraulic press. This paper introduced the open die forging process and manufacturing experience of large head forgings which cant be used for the reactor vessel of 1,000MW nuclear power plant.

• Journal of Korea Multimedia Society
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• v.24 no.10
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• pp.1403-1413
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• 2021

In this paper, we investigate automated data validation techniques for artificial intelligence training, and also disclose open-source frameworks, such as Google's TensorFlow Data Validation (TFDV), that support automated data validation in the AI model development process. We also introduce an experimental study using public data sets to demonstrate the effectiveness of the open-source data validation framework. In particular, we presents experimental results of the data validation functions for schema testing and discuss the limitations of the current open-source frameworks for semantic data. Last, we introduce the latest studies for the semantic data validation using machine learning techniques.

• Journal of Broadcast Engineering
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• v.18 no.5
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• pp.771-774
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• 2013

This study investigates the relationship between voice quality measurements and emotional states, in addition to conventional prosodic and cepstral features. Open quotient, harmonics-to-noise ratio, spectral tilt, spectral sharpness, and band energy were analyzed as voice quality features, and prosodic features related to fundamental frequency and energy are also examined. ANOVA tests and Sequential Forward Selection are used to evaluate significance and verify performance. Classification experiments show that using the proposed features increases overall accuracy, and in particular, errors between happy and angry decrease. Results also show that adding voice quality features to conventional cepstral features leads to increase in performance.

• Journal of the Korean Institute of Educational Facilities
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• v.4 no.3
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• pp.15-29
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• 1997

Open education started spontaneously in elementary school and accommodates positively as a result of educational reformation. Open education also contributes to the development of human nature. This developes a creative power and inhances independence according to a main task of school support for the 21st century. A premise of this study is how to fulfill a fresh and wide space field of learning which is an indispensable condition of open education. The study analysed the teachers' reactions to open education after classifying an atmosphere of reception, understanding concepts, and application. This examined the concept, basic principles, characteristics, teaching-learning activiters open education, and quality of learning. The method of research used was on the results from the percentages of questionnaires that were posted to the sample schools. Although the final outcome to open education can not be summarized, three preconclusions of open education are as follows; First an atmosphere of reception is spreading continuously day by day. Secondly, understanding the concept of open education is very important. Thirdly, go percent of all schools have experienced open education were applied to open education. Contrary to some affirmative reactions, there are some disadvantages to open education. incdule, poor educational environments, difficulty in managing schools, lack of repetition of old out-dated teaching skills. Finally in conclusion, we must learn to adapt to the new method of open education as our educational system for the 21st century can not simply rely upon the open education motto. Above all, we must support educational reform and enforce the development of education within the education act.

• Journal of the Korean Society for Library and Information Science
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• v.57 no.2
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• pp.79-96
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• 2023

This study analyzed the open peer review results for 585 papers in the field of social sciences in F1000Research, a representative OPR(Open Peer Review) platform, and checked the relationship between the number of cited-by, altmetrics and review score. In addition, by verifying whether the review score shows a moderating effect between the relationship between the utilization of the paper and the cited-by, it was confirmed whether the paper evaluated as high quality in the open review platform can promote the number of cited-by. As a result of the analysis, first, there was no significant difference in the number of cited-by between the approved and conditionally approved paper groups, but the converted review score and the number of cited-by showed a weak positive correlation (r = 0.40 - 0.60). Second, the review score showed a weak correlation with the altmetrics, and it was analyzed that review result could weakly predict the number of cited-by and social impact. Finally, it was verified that the review score performed a significant positive moderating effect (B=1.69, P < 0.01) in making the use of the paper lead to citation. As a result of the conditional effect test, it was verified that it showed the greatest effect(B=11.32, 95% CI [10.57, 12.08]) in the group of papers rated as the highest quality. Therefore, it was analyzed that the open review scores can help researchers select high quality papers and induce citations.