• Restorative Dentistry and Endodontics
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• v.30 no.4
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• pp.335-343
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• 2005

Hemolytic property is a specific feature of bacteria to obtain iron which is essential for its survival in host tissues. Therefore, it is thought to be one of several factors of virulence. The purpose of this study was to investigate the hemolytic properties of Prevotella nigrescens isolated from the teeth diagnosed as pulp necrosis and apical periodontitis under the presence of hemolysin inhibitors such as $NaN_3$ and dithiothreitol. heat, various pH and cultural conditions. The results were as follows; 1. Clinically isolated P. nigrescens strains and standard P. nigrscens ATCC 33563 showed hemolytic activity. 2. P. nigrescens showed higher hemolytic activity against human erythrocytes than sheep or horse erythrocytes. 3. $NaN_3$ and dithiothreitol (DTT) reduced the hemolytic activity of P. nigrescens in a dose dependent manner (p<0.05). 4. Optimal pH for the maximum hemolytic activity of P. nigrescens was 4.0 and the hemolysin was stable under the $50^{\circ}C$, but the hemolytic activity was significantly decreased at $95^{\circ}C$. 5. P. nigrescens cultured in $10\%\;CO_2$ condition showed higher hemolytic activity than the bacteria cultured in the anaerobic condition.

• KIPS Transactions on Software and Data Engineering
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• v.2 no.10
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• pp.713-722
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• 2013

This paper proposes a method of using depth information to detect the hand region in real-time based on the cascade method. In order to ensure stable and speedy detection of the hand region even under conditions of lighting changes in the test environment, this study uses only features based on depth information, and proposes a method of detecting the hand region by means of a classifier that uses boosting and cascading methods. First, in order to extract features using only depth information, we calculate the difference between the depth value at the center of the input image and the average of depth value within the segmented block, and to ensure that hand regions of all sizes will be detected, we use the central depth value and the second order linear model to predict the size of the hand region. The cascade method is applied to implement training and recognition by extracting features from the hand region. The classifier proposed in this paper maintains accuracy and enhances speed by composing each stage into a single weak classifier and obtaining the threshold value that satisfies the detection rate while exhibiting the lowest error rate to perform over-fitting training. The trained classifier is used to classify the hand region, and detects the final hand region in the final merger stage. Lastly, to verify performance, we perform quantitative and qualitative comparative analyses with various conventional AdaBoost algorithms to confirm the efficiency of the hand region detection algorithm proposed in this paper.

• Journal of The Geomorphological Association of Korea
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• v.20 no.4
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• pp.51-70
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• 2013

The characteristics of deposits formed by the Daejon-cheon and Soobuk-cheon, dissecting the mountains such as Byungpung Mt. and Samin Mt. in western part of Damyang county, Jeonmam province. Results from field survey and bore hole logging by KIGAM are used in interpreting depositional environment, in this study. By the result of deposits near of the channels Daejon-cheon and Soobuk-cheon, and main channel of Youngsan River, the depth of sediment layers in this area is 4~7m, far thinner than formerly estimated. Weathered material of local rocks forms the base of the sedimentary layers. It can be assumed that the location channel of the Youngsan river has been stable ever since the start of the sedimentary events. Sediment particles of tributaries are angular than those of Youngsan River. Particles are larger and sorting is poor. It is interpreted as mount flash flood deposits. Main sources of sediments at the valley bottom or deposition dominated area are the terrace deposits or slope deposits over the gentle foot-slope or front of surrounding mountains. Some particles show polygonal cracking on the surface originated from the strong chemical weathering, while most of these has high angularity. It means various geomorphic processes operate to produce and transport the particles in this area.Isolated hills within the sedimentary plains are made with weathered materials of local bedrock. In the case of foot-slope of the hills, thin sedimentary layers are found. So it can be concluded that surface features of deposition zone of the Daejon-cheon and Soobuk-cheon is formed by the filling of lower part of the valley and its feature partly controlled by the relief of the weathering front.

• Journal of Korean Philosophical Society
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• v.137
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• pp.357-381
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• 2016

${\ll}$Hua shu${\gg}$ is one of the Taoist scriptures written by Tan qiao, a taoist in the late Tang dynasty. The logical structure of his scriptures is very complicated, and its content is profound though it has few pages. To understand ${\ll}$Hua shu${\gg}$ precisely the key words which appear in the Taoism scriptures have been examined. The most important words are: 'Tao', 'Emptiness', 'Shape', and 'Variation'. Tan qiao tried to explain nature, human, and society changes by using these key words, and also asserted that humans can affect their change; we slow our aging, more or less; we prevent our society from its decay and make it stable, more or less. Tan qiao asserted the autonomous feature of humans in ${\ll}$Hua shu${\gg}$ which shows how man manages his own life rather than being stuck in his destiny. This goes the same for society. "One's destiny is not fixed but changeable through his efforts". In Taoism, humans are not beings who have no chance to make change other than living their given destinies but are autonomous. This is again what the Taoist Tan qiao wanted to make clear.

• Korean Journal of Optics and Photonics
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• v.31 no.1
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• pp.7-12
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• 2020

In this paper, we experimentally investigate the fiber fuse in single-mode 2-kW-class high-power fiber amplifiers, depending on the cooling method at the splicing point. We measured the temperature of the splicing point between the pump-signal combiner and gain fiber as a function of laser output power. The temperature of the splicing point increased from 20 to 32℃ with a slope of 0.01℃/W, up to 1.2 kW of laser output power. At higher powers the temperature of the splicing point increased dramatically, with a slope of 0.08℃/W. After that, the fiber amplifier was destroyed during operation at 1.96 kW of output power by fiber fuse. The bullet shape, a common feature of fiber fuse, was observed in the damaged passive fiber core of the pump-signal combiner. Later, we adopted an improved water-cooled cold plate to increase the cooling efficiency at the splicing point, and investigated the laser output power. The temperature at the splicing point was 35.8℃ with a temperature-rise slope of 0.007℃/W at the maximum output power of 2.05 kW. The beam quality M² was measured to be less than 1.3, and the output beam's profile was a stable Gaussian shape. Finally, neither fiber fuse nor mode instability was observed in the fiber amplifier at the maximum output power of 2.05 kW.

• The Korean Journal of Archival Studies
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• no.10
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• pp.145-194
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• 2004

Church archives are the evidential instruments to remember church activity and important information aggregate which has administrative, legal, financial, historical, faithful value as the collective memory of church community. So it must be managed necessarily and the management orders are based on the Bible. The western churches which have a correct understanding about the importance of church records and management order have taken multilateral endeavor to create, manage church archives systematically. On the other hand, korean churches don't have the records management systems. Therefore, Records created in individual church are mostly managed unsystematically and exist as 'backlogs', finally, they are destructed without reasonable formalities. In those problems, the purpose of this study is to offer the way of records classification and disposition instrument with recognition that records management should be done from the time of creation or previous to it. As a concrete device for them, I tried to embody the function-based classification method and disposal schedule. I prefer the function-based classification and disposal schedule to the organization and function-based classification to present stable classification and disposal schedule, as we can say the best feature of the modern organization is multilateral and also churches have same aspect. For this study, I applied DIRKS(Designing and Implementing Recordkeeping Systems) manual which National Archives of Australia provide and guidelines in ICA/IRMT series to construct the theory of the function-based classification in individual churches. Through them, it was possible to present a model for preliminary investigation, analysis of business activity, records survey, disposal schedule. And I took an example of 'Myong Sung Presbyterian Church' which belong to 'The Presbyterian church in Korea'. I explained in detail codifying process and results of preliminary investigation in 'Myong Sung Presbyterian Church', analysis of business activity based on it, process of presenting the function-based classification and disposal schedule got from all those steps. For establishing disposal schedule, I planned 'General Disposal Schedule' and 'Agency Disposal Schedule' which categorized 'general function' and 'agency function' of an agency, according to DIRKS in Australia and ICA/IRMT. And for estimation of disposal date I had a thorough grasp of important records category presented in 'Constitution of General Assembly', interview to know the importance of tasks, and added examples of disposal schedule in western church archives. This study has significance that it was intended to embody 'the function-based classification' and 'disposal schedule' suitable for individual church, applying DIRKS in Australia and ICA/IRMT on absence of the theory or example which tried to present the function-based classification and disposal schedule for individual church. Also it is meaningful to present a model that can classify and disposal real records according to the function in individual church which has no recognition or way about records management.

• Journal of Broadcast Engineering
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• v.24 no.3
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• pp.495-505
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• 2019

Typical algorithms of deep learning include CNN(Convolutional Neural Networks), which are mainly used for image recognition, and RNN(Recurrent Neural Networks), which are used mainly for speech recognition and natural language processing. Among them, CNN is able to learn from filters that generate feature maps with algorithms that automatically learn features from data, making it mainstream with excellent performance in image recognition. Since then, various algorithms such as R-CNN and others have appeared in object detection to improve performance of CNN, and algorithms such as YOLO(You Only Look Once) and SSD(Single Shot Multi-box Detector) have been proposed recently. However, since these deep learning-based detection algorithms determine the success of the detection in the still images, stable object tracking and detection in the video requires separate tracking capabilities. Therefore, this paper proposes a method of combining Kalman filters into deep learning-based detection networks for improved object tracking and detection performance in the video. The detection network used YOLO v2, which is capable of real-time processing, and the proposed method resulted in 7.7% IoU performance improvement over the existing YOLO v2 network and 20 fps processing speed in FHD images.

• Journal of the Korean Society of Radiology
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• v.15 no.4
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• pp.547-554
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• 2021

In order to quickly and accurately diagnose pneumonia on a chest X-ray image, different batch sizes of 4, 8, 16, and 32 were applied to the same Xception deep learning model, and modeling was performed 3 times, respectively. As a result of the performance evaluation of deep learning modeling, in the case of modeling to which batch size 32 was applied, the results of accuracy, loss function value, mean square error, and learning time per epoch showed the best results. And in the accuracy evaluation of the Test Metric, the modeling applied with batch size 8 showed the best results, and the precision evaluation showed excellent results in all batch sizes. In the recall evaluation, modeling applied with batch size 16 showed the best results, and for F1-score, modeling applied with batch size 16 showed the best results. And the AUC score evaluation was the same for all batch sizes. Based on these results, deep learning modeling with batch size 32 showed high accuracy, stable artificial neural network learning, and excellent speed. It is thought that accurate and rapid lesion detection will be possible if a batch size of 32 is applied in an automatic diagnosis study for feature extraction and classification of pneumonia in chest X-ray images using deep learning in the future.

• Asia Marketing Journal
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• v.13 no.4
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• pp.253-264
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• 2012

A growing number of Korean companies are trying to expand their business area into global market due to saturation in the Korean domestic market. Home shopping industry arriving on mature stage is faced with less growth recently. CJ O Shopping which is a top ranked home shopping company in Korea, has been showing meaningful performances by earlier moving to global market with thorough preparations. CJ O Shopping's global marketing strategy focused on asian countries including China, India, Vietnam, and Japan is going successfully, which enables top ranked on-line retailing company in asia as well as in Korea. CJ O Shopping effectively penetrated into overseas market with both core competence based on Korean home shopping model and rigorous preliminary study on target market. Especially shoppertainment (Shopping+Entertainment) that is unique feature of globally competitive Korean home shopping created huge differentiations in target market. Also choosing the influential local partner, sharing the business goals, and building the joint venture could make stable operations, thereby easily earning of well-established awareness from target consumers. A step ahead entry of competitors and intensive localization of CJ O Shopping's core competence for arriving safe in target market were additional key factors for global marketing success. We can extract above key factors for success as implications of case study on CJ O Shopping's global marketing, and expect those factors to be spread into lots of Korean companies and utilized as successful strategies for global marketing.

• KIPS Transactions on Software and Data Engineering
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• v.12 no.7
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• pp.303-314
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• 2023

Voice conversion, a technology that allows an individual's speech data to be regenerated with the acoustic properties(tone, cadence, gender) of another, has countless applications in education, communication, and entertainment. This paper proposes an approach based on the StarGAN-VC model that generates realistic-sounding speech without requiring parallel utterances. To overcome the constraints of the existing StarGAN-VC model that utilizes one-hot vectors of original and target speaker information, this paper extracts feature vectors of target speakers using a pre-trained version of Rawnet3. This results in a latent space where voice conversion can be performed without direct speaker-to-speaker mappings, enabling an any-to-any structure. In addition to the loss terms used in the original StarGAN-VC model, Wasserstein distance is used as a loss term to ensure that generated voice segments match the acoustic properties of the target voice. Two Time-Scale Update Rule (TTUR) is also used to facilitate stable training. Experimental results show that the proposed method outperforms previous methods, including the StarGAN-VC network on which it was based.