수면 호흡음을 이용한 폐쇄성 수면 무호흡 중증도 분류

학위논문 (박사)-- 서울대학교 융합과학기술대학원 융합과학부, 2017. 8. 이교구.Obstructive sleep apnea (OSA) is a common sleep disorder. The symptom has a high prevalence and increases mortality as a risk factor for hypertension and stroke. Sleep disorders occur during sleep, making it difficult for patients to self-perceive themselves, and the actual diagnosis rate is low. Despite the existence of a standard sleep study called a polysomnography (PSG), it is difficult to diagnose the sleep disorders due to complicated test procedures and high medical cost burdens. Therefore, there is an increasing demand for an effective and rational screening test that can determine whether or not to undergo a PSG. In this thesis, we conducted three studies to classify the snoring sounds and OSA severity using only breathing sounds during sleep without additional biosensors. We first identified the classification possibility of snoring sounds related to sleep disorders using the features based on the cyclostationary analysis. Then, we classified the patients OSA severity with the features extracted using temporal and cyclostationary analysis from long-term sleep breathing sounds. Finally, the partial sleep sound extraction, and feature learning process using a convolutional neural network (CNN, or ConvNet) were applied to improve the efficiency and performance of previous snoring sound and OSA severity classification tasks. The sleep breathing sound analysis method using a CNN showed superior classification accuracy of more than 80% (average area under curve > 0.8) in multiclass snoring sounds and OSA severity classification tasks. The proposed analysis and classification method is expected to be used as a screening tool for improving the efficiency of PSG in the future customized healthcare service.Chapter 1. Introduction ................................ .......................1 1.1 Personal healthcare in sleep ................................ ..............1 1.2 Existing approaches and limitations ....................................... 9 1.3 Clinical information related to SRBD ................................ .. ..12 1.4 Study objectives ................................ .........................16 Chapter 2. Overview of Sleep Research using Sleep Breathing Sounds ........... 23 2.1 Previous goals of studies ................................ ................23 2.2 Recording environments and related configurations ........................ 24 2.3 Sleep breathing sound analysis ................................ ...........27 2.4 Sleep breathing sound classification ..................................... 35 2.5 Current limitations ................................ ......................36 Chapter 3. Multiple SRDB-related Snoring Sound Classification .................39 3.1 Introduction ................................ .............................39 3.2 System architecture ................................ ......................41 3.3 Evaluation ................................ ...............................52 3.4 Results ................................ ..................................55 3.5 Discussion ................................ ...............................59 3.6 Summary ................................ ..................................63 Chapter 4. Patients OSA Severity Classification .............................65 4.1 Introduction ................................ .............................65 4.2 Existing Approaches ................................ ......................69 4.3 System Architecture ................................ ......................70 4.4 Evaluation ................................ ...............................85 4.5 Results ................................ ..................................87 4.6 Discussion ................................ ...............................94 4.7 Summary ................................ ..................................97 Chapter 5. Patient OSA Severity Prediction using Deep Learning Techniques .....99 5.1 Introduction ................................ .............................99 5.2 Methods ................................ ..................................101 5.3 Results ................................ ..................................109 5.4 Discussion ................................ ...............................115 5.5 Summary ................................ ..................................118 Chapter 6. Conclusions and Future Work ........................................120 6.1 Conclusions ................................ ..............................120 6.2 Future work ................................ ..............................127Docto

열린충남 7호-[정책제언]대전·충남지역 지방은행의 경쟁력 강화방안

Ⅰ. 머리말 1967년 부산은행과 대구은행의 설립을 시작으로 지역경제의 발전을 위한 자금공급 및 지역의 금융 중개기능 강화를 목표로 전국 각 시도에 설립된 모두 10개의 지방은행은 1970년대 이래 괄목할 만한 성장을 이루어 왔다. 이러한 지방은행은 그 동안의 빠른 성장 속에서 시중은행보다 높은 수익성을 유지하여 온데 대해 주목을 받고 있다. 그러나 지역적 제한 및 중소기업 대출위주의 영업제약과 이에 대한 보상조치로서 金利면의 우대라는 틀 속에서 성장해 온 지방은행이 과연 변화되고 있는 금융환경 하에서도 과거의 성장추세를 유지할 수 있을 것인가에 대해서는 의문의 여지가 있다고 할 수 있다. -이후 생략1. 머리말 2. 대전·충남지역 지방은행의 현황 3. 대전·충남 지역금융의 문제와 개선책 4. 대전·충남지역 지방은행의 발전방향 5. 대전·충남지역 지방은행의 경쟁력 강화방안 6. 맺는

Real-time disk scheduling for multimedia document playback

학위논문(석사) - 한국과학기술원 : 전산학과, 1997.8, [ ii, 40 p. ]한국과학기술원 : 전산학과

열린충남 7호-[통합본]열린충남 7호 (1997, 봄)

[특집]충남농업의 VISION과 대응전략 충남농업의 어제와 오늘 _ 이종상 Ⅰ. 서론 최근 수년간 한국농업은 국내외적으로 많은 변화를 겪어 왔다. -이후 생략 [정책제언] 대전·충남지역 지방은행의 경쟁력 강화방안 _ 김재필 Ⅰ. 머리말 1967년 부산은행과 대구은행의 설립을 시작으로 지역경제의 발전을 위한 자금공급 및 지역의 금융 중개기능 강화를 목표로 전국 각 시도에 설립된 모두 10개의 지방은행은 1970년 이래 괄목할 만한 성장을 이루어 왔다. -이후 생략 [시사칼럼]충남농정의 전개방향 _ 남궁영 Ⅰ. 추진배경 지난 94년, UR이 타결되고 WTO의 신국제경쟁사회가 열리면서 우리 농업에 대한 걱정의 소리와 우리 농민들의 앞날에 대한 불안감이 최고조에 달했다. -이후 생략 [연구원소식]연구원사업 연구원 시무식 丁丑年 한 해를 새롭게 시작하는「97년도 시무식」이 지난 1월 3일(金) 오전 10시 안승주 원장을 비롯한 전 직원이 참석한 가운데 본원 회의실에서 개최되었다. -이후 생략[특집]충남농업의 VISION과 대응전략 충남농업의 어제와 오늘 _ 이종상 21세기 한국농업의 발전전략과 미래모습 _ 조재환 개방화 시대에 있어서 충남농업의 대응전략 _ 최병익 농산물 유통구조 개선방안 _ 정태호 [정책제언] 대전·충남지역 지방은행의 경쟁력 강화방안 _ 김재필 서산기지 민항취항과 지역사회 파급효과 _ 이인배 [시사칼럼]충남농정의 전개방향 _ 남궁영 [연구원소식]연구원사업·원장동정·연구원활

Application of perylene dyes for low dielectric hybrid-type black matrices

Two perylene dyes having different absorption ranges were synthesized for an application in liquid crystal display black matrix. Hybrid-type and dye only-type black matrices were fabricated using the synthesized dyes and carbon black. Among the fabricated films, the hybrid-type film, which contained the same weight ratio of the dyes and carbon black showed high thermal and optical properties and had a low dielectric constant. Additionally, the surface of the film had low root-mean-squared roughness (Rq) value and was sufficiently flat in comparison to the film containing different chromophores that showed self-aggregation of the dyes described in previous research. (C) 2018 Published by Elsevier B.V. on behalf of The Korean Society of Industrial and Engineering Chemistry.OAIID:RECH_ACHV_DSTSH_NO:T201824097RECH_ACHV_FG:RR00200001ADJUST_YN:EMP_ID:A001061CITE_RATE:4.179DEPT_NM:재료공학부EMAIL:[email protected]_YN:YN

Improving nanoparticle dispersions of pigment and its application to a color filter: New phthalocyanine derivatives as synergist

Four synergists were synthesized to enhance pigment nanoparticles dispersion and the contrast ratio. The interaction between the synergist and the dispersant was confirmed by infra-red (IR) spectrometry. We demonstrate that the hydrogen bonds forming between the synergist and the dispersant act as a key factor. To analyze the dispersion properties, dynamic light scattering (DLS), and electron microscopic analysis was examined. The spectral and color characteristics was also measured by UV-vis spectrometry and colorimetry, and the contrast ratio of color filters was evaluated. This study confirms that the prepared synergist can increase the contrast ratio of green color filter. (C) 2017 The Korean Society of industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.OAIID:RECH_ACHV_DSTSH_NO:T201824087RECH_ACHV_FG:RR00200001ADJUST_YN:EMP_ID:A001061CITE_RATE:4.179DEPT_NM:재료공학부EMAIL:[email protected]_YN:YN

Aryloxy- and chloro-substituted zinc(II) phthalocyanine dyes: Synthesis, characterization, and application for reducing the thickness of color filters

In the development of display devices, a color filter is still considered an indispensable component. For a thinner display panel, the thickness of the color filter also needs to be decreased. However, if the thickness of the color filter is reduced, the color properties, including the color purity and color gamut are simultaneously diminished. Therefore, introduction of new colorants is needed to lower the thickness without diminishing the color performance. In this study, four phthalocyanine green dyes were synthesized for use in color filters. The molecular geometry and absorption properties were predicted by density functional theory (DFT) and time-dependent DFT, and UV-Vis spectroscopy was employed to measure the optical properties. The thermal stabilities of the dyes were examined by thermogravimetric analysis. A dye with suitable solubility and color properties was adopted in the color filter, and the optical properties and thickness of the dye-based color filter were compared to those of the pigment-based color filter. The chromatic performance and thickness of the color filter were determined by color spectrometry and Alpha step, respectively. Finally, we confirmed that the dye could enable the decrease in the thickness of the filter and provide a superior color property.OAIID:RECH_ACHV_DSTSH_NO:T201824103RECH_ACHV_FG:RR00200001ADJUST_YN:EMP_ID:A001061CITE_RATE:3.767DEPT_NM:재료공학부EMAIL:[email protected]_YN:YN

Effect of weakly coordinating anions on photo-stability enhancement of basic dyes in organic solvents

Weakly coordinating anions (WCAs) offer two succinct advantages when they are introduced as counter anions in a dye. First, replacing strong electrostatic attraction between a cationic dye and its counter anion with the relatively weak electrostatic attraction from a WCA can improve photo-stability of the dye due to charge distribution. Second, the steric hindrance due to the WCAs forms a spatial obstacle between the unstable charged site of the cationic dye and an external element that may degrade the dye. In this study, WCAs are introduced as counter anions in basic dyes to improve their photostability. Basic Yellow 1, Rhodamine 6G, and Rhodamine B were selected as dyes due to their particularly low photostabilities among cationic dyes. Three WCAs were investigated, where two were composed of anions surrounded by fluorine moieties (hexafluorophosphate and bis(trifluoromethane)sulfonimide), and one is surrounded by oxygen moieties (bis(oxalate)borate) Upon dissolving these dyes in three different organic solvents (Chloroform, Methylene Chloride, and Dimethylformamide), the photostabilities of almost all the WCA-substituted dyes were comparatively improved. The photo-stability of each WCA-substituted dye was especially improved in low polarity solvents and the bis(trifluoromethane)sulfonamide-basic dye pairs showed the highest photo-stabilities among four anion-dye pairs including the unsubstituted dyes.OAIID:RECH_ACHV_DSTSH_NO:T201824118RECH_ACHV_FG:RR00200001ADJUST_YN:EMP_ID:A001061CITE_RATE:3.767DEPT_NM:재료공학부EMAIL:[email protected]_YN:YN