• Journal of the Korea Society of Computer and Information
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• v.20 no.2
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• pp.113-120
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• 2015

Technology analysis is to analyze technological data such as patent and paper for a given technology field. From the results of technology analysis, we can get novel knowledge for R&D planing and management. For the technology analysis, we can use diverse methods of statistics. Time series analysis is one of efficient approaches for technology analysis, because most technologies have researched and developed depended on time. So many technological data are time series. Time series data are occurred through time. In this paper, we propose a methodology of technology forecasting using the dynamic time warping (DTW) of time series analysis. To illustrate how to apply our methodology to real problem, we perform a case study of patent documents in target technology field. This research will contribute to R&D planning and technology management.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.165-168
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• 2000

This paper presents the tracking resistance and mechanical strength due to boiling absorption of epoxy resin. The single network structure specimen(E series) formed of epoxy alone and interpenetrating polymer network(IPN) structure specimen(EM series) which epoxy resin was taken as first network and methacrylic acid resin as second network were manufactured. As adding $SiO^2$ filler classified by o[phr], 50[phr] and 100[phr] to those specimens, six kinds of specimens were manufactured and boiled in water during 2, 4, 8, 16, 32 and 64[hours]. As a result, it was confirmed that the tracking breakdown time of E series showed a abrupt decrease with boiling time increasing, but that of EM series was decreasing smoothly. Also, it was verified that the degrading rates of mechanical strength was lowerd according to improvement of adhension strength in case of EM series.

• Proceedings of the Korea Information Processing Society Conference
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• 2023.05a
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• pp.377-379
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• 2023

Concept drift detection on data stream is the major issue to maintain the performance of the machine learning model. Since the online stream is to be a function of time, the classical statistic methods are hard to apply. In particular case of seasonal time series, a novel window strategy with Fourier analysis however, gives a chance to adapt the classical methods on the series. We explore the KS-test for an adaptation of the periodic time series and show that this strategy handles a complicate time series as an ordinary tabular dataset. We verify that the detection with the strategy takes the second place in time delay and shows the best performance in false alarm rate and detection accuracy comparing to that of arbitrary window sizes.

• Journal of Society of Preventive Korean Medicine
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• v.25 no.3
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• pp.39-55
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• 2021

Objective : To investigate specific prescriptions, herbal medicines and treatment strategy, this study systematically reviewed case studies on traditional Chinese medicine (TCM) treatment for childhood cancer. Method : Literature searches were performed on database of China National Knowledge Infrastructure (CNKI). Studies published before December 2020 were categorized and analyzed according to the treatment strategy and we also investigated Chinese herbs used in the prescriptions. Results : Twenty-five studies including 17 case series and 8 single case reports were included in our review. Of the total 439 patients, 379 (85.7%) had leukemia and other myeloplastic disease. Conventional western medicine (CWM) treatment was also used with TCM based on the syndrome identification. Most studies reported favorable effect of combination treatment with CWM and TCM. Among 266 herbs in the studies, reinforcing herbs were more frequently used than anti-cancer herbs. Conclusion : Traditional herbal treatment for childhood cancer should be performed considering the syndrome identification as well as stage of CWM. Reinforcing herbs should be more focused because of the fragility and growth of the childhood.

• Journal of the Korean Society for Railway
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• v.2 no.1
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• pp.38-46
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• 1999

This study proposes the analysis and evaluation method of time series ultrasonic signal using the attractor analysis. Features extracted from time series signal analyze quantitatively characteristics of weld defects. For this purpose, analysis objective in this study is fractal dimension and attractor quadrant feature. Trajectory changes in the attractor indicated a substantial difference in fractal characteristics resulting from distance shifts such as parts of head and flange even though the types of defects are identified. These differences in characteristics of weld defects enables the evaluation of unique characteristics of defects in the weld zone. In quantitative fractal feature extraction, feature values of 3.848 in the case of part of head(crack) and 4.102 in the case of part of web(side hole) and 3.711 in the case of part of flange(crack) were proposed on the basis of fractal dimensions. Proposed attractor feature extraction in this study can enhance the precision rate of ultrasonic evaluation for defect signals of rail weld zone such as side hole and crack.

• Journal of Chest Surgery
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• v.4 no.2
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• pp.101-106
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• 1971

Forty-seven cases of bronchiectasis were admitted in this department, of which 38 cases were reviewed. Pulmonary tuberculosis was the most frequent associated disease and encountered in 42% in this series. Preoperative bronchogram performed in 38 cases revealed left lung involvement in 21 cases,right lung in 14 cases, both lungs in 3 cases, and multilobar involvement in 10 cases. Various types of pulmonary resection were performed on 32 patients. Complication developed in 3 cases [9.4%]. One patient died of intraoperative hypoxia on the second post-operative day. Second case was Complicated with hydrothorax, and third case was with hemothorax. In 81% of this series, the result was satisfactory and 3 cases [10%] showed slight improvement of symptoms, and 2 cases show no improvement. The mortality rate was 3 percent(1case).

• Journal of Welding and Joining
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• v.18 no.5
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• pp.77-83
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• 2000

This study proposes the analysis and evaluation method of time series ultrasonic signal using the attractor analysis. Features extracted from time series signal analyze quantitatively characteristics of weld defects. For this purpose, analysis objective in this study is fractal dimension and attractor quadrant feature. Trajectory changes in the attractor indicated a substantial difference in fractal characteristics resulting from distance shifts such as parts of head and flange even though the types of defects are identified. These difference in characteristics of weld defects enables the evaluation of unique characteristics of defects in the weld zone. In quantitative fractal feature extraction, feature values of 3.848 in the case of part of head(crack) and 4.102 in the case of part of web(side hole) and 3.711 in the case of part of flange(crack) were proposed on the basis of fractal dimensions. Proposed attractor analysis and DAC in this study can enhance the precision rate of ultrasonic evaluation for defect signals of rail weld zone such as side hole and crack.

• Proceedings of the KSR Conference
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• 1998.11a
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• pp.87-95
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• 1998

This study proposes the analysis and evaluation method of time series ultrasonic signal using the attractor analysis. Features extracted from time series signal analyze quantitatively characteristics of welding defects. For this purpose, analysis objective in this study is fractal dimension and attractor Quadrant feature. Trajectory changes in the attractor indicated that even the same type of defects carried substantial difference in fractal characteristics resulting from distance shifts such as parts of head and flange. Such differences in characteristics of weld defects enables the evaluation of unique features of defects in the weld zone. In quantitative fractal feature extraction, feature values of 3.848 in the case of part of head(crack) and 4.102 in the case of part of web(side hale) and 3.711 in the case of part of flange(crack) were proposed on the basis of fractal dimensions. Proposed attractor feature extraction in this study can enhance the precision rate of ultrasonic evalaution for defect signals of rail weld zone such as side hole and crack.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.2
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• pp.199-208
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• 2012

This paper proposes a quasi Z-source DVR(Dynamic Voltage Restorer) system with a series connection of the output terminals, to compensate the voltage variations in the 6.6[kV]/60[Hz] power distribution system. The conventional DVR using one quasi Z-source AC-AC converter has the advantage which it can compensate the voltage variations without the need for the additional energy storage device such as a battery, but it is impossible to compensate for the 50[%] under voltage sags. To solve this problem, a DVR system using two quasi Z-source AC-AC converters with the series connection of the output terminals is proposed. By controlling the duty ratio D in the buck-boost mode, the proposed system can control the compensation voltage. For case verification of the proposed system, PSIM simulation is achieved. As a result, in case that the voltage sags-swells occur 10[%], 20[%], 60[%] in power distribution system, and, in case that the 50[%] under voltage sags-swells continuously occur, all case could compensate by the proposed system. Especially, the compensated voltage THD was examined under the condition of the 10[%]~50[%] voltage sags and the 20[${\Omega}$]~100[${\Omega}$] load changes. The compensated voltage THD was worse for the higher load resistances and more severe voltage sags. Finally, In case of the voltage swells compensation, the compensation factor has approached nearly 1 regardless of the load resistance changes, while the compensation factor of voltage sags was related to the load variations.

• The Journal of Korean Obstetrics and Gynecology
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• v.31 no.4
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• pp.128-146
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• 2018

Objectives: This study was performed to analyze the prescriptions of Korean herbal medicine which had been commonly used during postpartum period. Methods: We searched literature on postpartum cares with Korean Herbal medicine in 4 domestic search engines. After that, we conducted eligibility screening based on inclusion and exclusion criteria. Results: 1. We selected total 48 studies. There were 40 clinical studies (25 case reports and 15 case series) and 8 animal experimental studies. 2. Of the 40 clinical studies, other treatments were used together with herbal medicine : acupuncture (28), chuna manipulation (3), and pharmacopuncture (5). 3. Of the 25 case reports, the most common symptoms were musculoskeletal symptoms (8), followed by mental disorders including postpartum depression (5). Various prescriptions of herbal medicine were used depending on the diseases or symptoms. 4. In 15 case series, 665 subjects in 11 case series had taken Saenghwa-tang-gagam within 1~2 weeks after childbirth, and the average duration of Saenghwa-tang-gagam administration were $9{\pm}4.97$ days. 498 subjects in 9 studies were breast-feeding, and there were no side effects reported. 5. All experimental studies were about the recovery, the immunity and the breast-feeding associated puerperal characteristics. Also, 3 studies used Saenghwa-tang as an intervention. Conclusions: Saenghwa-tang can be commonly used for the purpose of prevention and care of the postpartum symptoms within the first 1~2 weeks after childbirth for 10 days. Also, various prescriptions of herbal medicine may be used depending on the diseases or symptoms, and can be conducted with other treatments like acupuncture, cupping, moxibustion, pharmacopuncture and chuna manipulation.