• 한국철도학회논문집
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• 제2권1호
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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 Welding and Joining
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• 제18권5호
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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.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 추계학술대회 논문집
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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.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.609-615
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• 2001

This study proposes analysis and evaluation method of time series ultrasonic signal using attractor analysis for fusion joint part of polyethylene piping. Quantitatively characteristics of fusion joint part is analysed features extracted from time series. Trajectory changes in the attractor indicated a substantial difference in fractal characteristics. These differences in characteristics of fusion joint part enables the evaluation of unique characteristics of fusion joint part. In quantitative fractal feature extraction, feature values of 4.291 in the case of debonding and 3.694 in the case of bonding were proposed on the basis of fractal dimensions. In quantitative quadrant feature extraction, 1,306 point in the case of bonding(one quadrant) and 1,209 point(one quadrant) in the case of debonding were proposed on the basis of fractal dimensions. Proposed attractor feature extraction can be used for integrity evaluation of polyethylene piping material which is in case of bonding or debonding.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제49권1호
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• pp.2-12
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• 2023

The current study aimed to explore the types and frequencies of uncommon complications associated with third molar extractions based on a scoping review of case reports and case series. The study used an electronic literature search based on PubMed and Embase up to March 31, 2020, with an update performed on October 22, 2021. Any case reports and case series that reported complications associated with third molar extractions were included. The types of complications were grouped and the main symptoms of each type of complication were summarized. A total of 51 types of uncommon complications were identified in 248 patients from 186 studies. Most types of complications were post-operative. In the craniofacial and cervical regions, the most frequent complications included iatrogenic displacement of the molars or root fragments in the craniofacial area, late mandibular fracture, and subcutaneous emphysema. In other regions, the most frequent complications include pneumomediastinum, pneumorrhachis, pneumothorax, and pneumopericardium. Of the patients, 37 patients had life-threatening uncommon complications and 20 patients had long-term/irreversible uncommon complications associated with third molar extractions. In conclusion, a variety of uncommon complications associated with third molar extractions were identified. Most complications occurred in the craniofacial and cervical regions and were mild and transient.

• 대한원격탐사학회지
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• 제36권4호
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• pp.527-534
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• 2020

This study aims to monitor the displacement of the bridges using Stanford Method for Persistent Scatterers (StaMPS) time-series Persistent Scatterer Interferometric Synthetic Aperture Radar analysis. For case study bridges: Kimdaejung bridge and Deokyang bridge, we acquired 60 and 33 Cosmo-Skymed Synthetic Aperture Radar (SAR) data over the Mokpo region and Yeosu region, respectively from 2013 to 2019. With single-look interferograms, we estimated the long-term time-series displacements over the bridges. The time-series displacements were estimated as -8.8 mm/year and -1.34 mm/year at the mid-span over the selected bridges: Kimdaejung and Deokyang bridge, respectively. This time-series displacement provides reliable and high spatial resolution information to monitor the structural behavior of the bridge for preventing structural behaviors.

• 응용통계연구
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• 제33권2호
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• pp.203-213
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• 2020

자기-대조 환자군(self-controlled case series; SCCS) 연구는 별도의 대조군 없이 환자의 비노출기간을 대조기간으로 설정하여 노출기간에 대한 상대적인 발생 위험도를 측정하는 역학 연구의 한 방법이다. 이 방법은 대조군을 선정할 때 발생하는 편의를 최소화할 수 있는 장점이 있어서 약물 복용 후 이상반응 발생 위험도를 측정하기 위한 방법으로 전통적으로 많이 사용되어왔다. 본 연구는 SCCS 연구를 바탕으로 두 개 이상의 약물을 동시에 사용했을 때 그 부작용의 위험이 어떻게 증가하는지 살펴보고자 한다. 마약성 진통제 유사체인 tramadol과 다빈도 병용 약물 간 약물상호작용에 대해 조건부 포아송 모형을 가정하고 분석하였다. 이때 베이지안 추론법을 사용하여 최대가능도추정량이 지니고 있는 과대적합 문제를 해결하며, 사전분포의 민감도를 측정하기 위해 정규 사전분포와 라플라스 사전분포를 가정하여 모형화하였다.

• 대한한방부인과학회지
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• 제28권2호
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• pp.143-155
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• 2015

Objectives : Chronic pelvic pain (CPP) is a common gynecologic symptoms. Various diseases, specially irritable bowel syndrome (IBS), ovarian cysts, and endometriosis, can occur CPP, but the medicines and the operations which used on these diseases have many side effects and even if patients get treatments, pain usually remain due to the pathology is not accord with the pain or the cause is not clear. There are some cases about effective of the Korean medicine therapies, but cases are still deficiency and case series has not been reported. We have a case series of CPP treated by Korean medicine treatment, so we report a case series on CPP. Methods : 6 patients, who suffered from CPP, were enrolled in this study. They received Korean medicine therapies such as herbal medicine, moxibustion, and acupuncture. Results : CPP was reduced by Korean medicine therapies. Conclusions : The present study suggests that Korean medicine therapies have a effect on CPP.

• 동의신경정신과학회지
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• 제22권4호
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• pp.11-20
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• 2011

Objectives : The purpose of this study was to obtain some knowledge about the scalp acupuncture treatment on Parkinson's disease for the future practice and the research from the clinical studies in China. Methods : The literatures were searched using the database-China Academic Journals(CAJ) (2006-2011). Clinical studies of scalp acupuncture for Parkinson's disease-Randomized controlled trial(RCT), case control study, case series, case report- were included. Results : Of 65 articles, 12 Clinical studies met our inclusion criteria. Three case series reported a significant improvement in the patients with Parkinson's disease by scalp acupuncture, and 9 RCTs reported a significant effectiveness of scalp acupuncture as a monotherapy or as a combination therapy with Madopa Tablet(Levodopa + Benserazide HCl) treatment. Conclusions : The results of this study could be used for the future study about scalp acupuncture for Parkinson's disease.

• 한국콘텐츠학회논문지
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• 제8권2호
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• pp.100-115
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• 2008

최근 들어 해외 메이저급 애니메이션 회사들이 TV애니메이션을 플래쉬 프로그램으로 제작하기 시작하면서 국내 애니메이션 업계의 OEM 하청업체들은 뒤늦게 플래쉬 애니메이션의 제작 기술을 도입하기 시작했다. 하지만 아직까지 애니메이션 기술과 플래쉬 활용 기술을 모두 완벽하게 소화할 수 있는 인력은 얼마 되지 않는다. 또한 교육기관이나 학원에서도 모바일과 웹에 치중한 플래쉬 교육으로 인하여 전문 TV애니메이션을 제작할 수 있는 시스템이 갖추어지지 않고 있다. 분석 결과, 플래쉬 프로그램은 사용자의 편의성, 타 프로그램과의 호환성, 제작비의 절감효과 등의 장점으로 인하여 TV방영용 애니메이션을 제작하기에 매우 적합한 프로그램으로 결론 내린다. 현재 해외에서 제작하는 플래쉬 애니메이션의 제작 파이프라인을 도입, 체계화하여 매뉴얼을 구축하고 실무 제작에 적용시켜 국내 TV용 플래쉬 애니메이션의 질적 수준의 향상과 더불어 높은 경쟁력을 가진 애니메이션 제작에 도움이 되었으면 하는 바램이다.