연성 및 생재흡수성 전자소자용 비휘발성 메모리 소자와 집적센서 구현

학위논문 (박사)-- 서울대학교 대학원 : 화학생물공학부, 2015. 8. 김대형.Over years, major advances in healthcare have been made through research in the fields of nanomaterials and microelectronics technologies. However, the mechanical and geometrical constraints inherent in the standard forms of rigid electronics have imposed challanges of unique integration and therapeutic delivery in non-invasive and minimally invasive medical devices. Here, we describe two types of multifunctional electronic systems. The first type is wearable-on-the-skin systems that address the challenges via monolithic integration of nanomembranes fabricated by top-down approach, nanotubes and nanoparticles assembled by bottom-up strategies, and stretchable electronics on tissue-like polymeric substrate. The system consists of physiological sensors, non-volatile memory, logic gates, and drug-release actuators. Some quantitative analyses on the operation of each electronics, mechanics, heat-transfer, and drug-diffusion characteristic validated their system-level multi-functionalities. The second type is a bioresorbable electronic stent with drug-infused functionalized nanoparticles that takes flow sensing, temperature monitoring, data storage, wireless power/data transmission, inflammation suppression, localized drug delivery, and photothermal therapy. In vivo and ex vivo animal experiments as well as in vitro cell researches demonstrate its unrecognized potential for bioresorbable electronic implants coupled with bioinert therapeutic nanoparticles in the endovascular system. As demonstrations of these technologies, we herein highlight two representative examples of multifunctional systems in order of increasing degree of invasiveness: electronically enabled wearable patch and endovascular electronic stent that incorporate onboard physiological monitoring, data storage, and therapy under moist and mechanically rigorous conditions.Contents Abstract Chapter 1. Introduction 1.1 Organic flexible and wearable electronics.................................................. 1 1.2 Inorganic flexible and wearable electronics............................................... 14 1.3 Flexible non-volatile memory devices.......................................................... 25 1.4 Bioresorbable materials and devices........................................................... 34 References Chapter 2. Multifunctional wearable devices for diagnosis and therapy of movement disorders 2.1 Introduction ................................................................................. 45 2.2 Experimental Section ......................................................................... 49 2.3 Result and Discussion ........................................................................ 65 2.4 Conclusion ................................................................................... 95 References Chapter 3. Stretchable Carbon Nanotube Charge-Trap Floating-Gate Memory and Logic Devices for Wearable Electronics 3.1 Introduction ................................................................................ 101 3.2 Experimental Section ........................................................................ 104 3.3 Result and Discussion ....................................................................... 107 3.4 Conclusion .................................................................................. 138 References Chapter 4. Bioresorbable Electronic Stent Integrated with Therapeutic Nanoparticles for Endovascular Diseases 4.1 Introduction ................................................................................ 148 4.2 Experimental Section ........................................................................ 151 4.3 Result and Discussion ....................................................................... 173 4.4 Conclusion .................................................................................. 219 References 국문 초록 (Abstract in Korean) .................................................................. 230Docto

Matrix Factorization for Recommendation Systems Utilizing Text Data

학위논문 (석사)-- 서울대학교 대학원 : 공과대학 전기·정보공학부, 2018. 2. 심규석.많은 회사들이 매출을 늘리기 위하여 추천시스템을 사용하고 있다. 행렬 분해법은 추천 시스템에서 주로 사용되는 방법 중 하나로, 사용자의 선호도를 근거로 하여 제품을 추천한다. 그러나, 전자거래가 발전 하면서, 제품과 사용자의 수가 증가했고 데이터 희소성 문제로 인해 정확한 추천이 힘들어졌다. 이러한 문제를 해결하기 위해 제품과 관련된 텍스트 데이터를 사용하는 행렬 분해법이 최근 제안되었다. 제안된 방법 중 컨볼루션 뉴럴 네트워크를 이용하여 텍스트 데이터로부터 특징 벡터를 추출하여 제품을 추천하는 방법이 효과적이다. 하지만 기존 연구는 단어 수준으로 텍스트 데이터를 고려하기 때문에 학습 해야 하는 파라미터의 수가 많은 등의 문제가 발생한다. 본 논문에서는 문자 단위 컨볼루션 뉴럴 네트워크를 사용하여 추천을 위해 효과적으로 문자 단위 특징을 뽑아내는 행렬 분해법을 제안한다. 또한 제안하는 행렬 분해법의 성능을 검증하기 위하여 실제 데이터를 이용하여 실험을 진행하였다.제 1 장 서론 1 제 1 절 연구의 배경 및 내용 1 제 2 장 관련 연구 3 제 1 절 행렬 분해법 3 제 2 절 컨볼루션 뉴럴 네트워크 6 제 3 절 문자 단위 텍스트 분석 9 제 3 장 제안하는 행렬 분해법 11 제 1 절 문자 단위 컨볼루션 뉴럴 네트워크 구조 11 제 2 절 최적화 과정 14 제 4 장 실험 16 제 1 절 실험 환경 및 실험 데이터 16 제 2 절 성능 측정 지표 및 세부사항 18 제 3 절 실험 결과 및 분석 19 제 5 장 결론 23 참고문헌 24 Abstract 26Maste

Length dependency expectation of negative bias temperature instability

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Channel with dependence of AC stress on bulk nMOSFETs

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완성창 절단 계획 알고리즘 개발

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Effect of rapid fluid administration on the prognosis of septic shock patients with isolated hyperlactatemia: A prospective multicenter observational study

Background: We aimed to investigate the association between initial fluid resuscitation in septic shock patients with isolated hyperlactatemia and outcomes. Methods: This multicenter prospective study was conducted using the data from the Korean Shock Society registry. Patients diagnosed with isolated hyperlactatemia between October 2015 and December 2018 were included and divided into thosewho received 30 mL/kg of fluid within 3 or 6 h and thosewho did not receive. The primary outcome was in-hospital mortality; the secondary outcomes were intensive care unit (ICU) admission, length of ICU stay, mechanical ventilation, and renal replacement therapy (RRT). Results: A total of 608 patients were included in our analysis. The administration of 30 mL/kg crystalloid within 3 or 6 h was not significantly associated with in-hospital mortality in multivariable logistic regression analysis ([OR, 0.8; 95% CI, 0.52?1.23, p=0.31], [OR, 0.96; 95% CI, 0.59?1.57, p=0.88], respectively). The administration of 30 mL/kg crystalloid within 3-h was not significantly associated with mechanical ventilation and RRT ([OR, 1.19; 95% CI, 0.77?1.84, p=0.44], [OR, 1.2; 95% CI, 0.7?2.04, p=0.5], respectively). However, the administration of 30 mL/kg crystalloid within 6 h was associated with higher ICU admission and RRT ([OR, 1.57; 95% CI, 1.07?2.28, p = 0.02], [OR, 2.08; 95% CI, 1.19?3.66, p = 0.01], respectively). Conclusions: Initial fluid resuscitation of 30 mL/kg within 3 or 6 h was neither associated with an increased or decreased in-hospital mortality in septic shock patients with isolated hyperlactatemia