마인드 맵과 반복결정트리를 이용한 갑상선 결절 외과치료 CDSS를 위한 임상 지식 모델링

유형원,최준영,한호성,Maqbool Hussain,이승룡 한국통신학회 2020 정보와 통신 Vol.37 No.9

본고에서는 마인드 맵(Mind Map)과 반복 결정 트리(Iterative Decision Tree, IDT)를 사용하여 임상 진료 지침(Clinical Practice Guidelines, CPG)과 의료 지식을 기반으로 갑상선결절 치료를 위한 임상의사결정지원시스템(Clinical Decision Support System, CDSS)을 개발하였다. 마인드 맵은 CPG에서 추출한 임상 모델을 표현하기 위해 사용되었고, 의사와 지식 공학자가 마인드 맵을 분석하고 이를 IDT로 변환하였다. IDT로부터 추출한 최종 지식 모델은 일련의 규칙으로 표현되었다. 2015년 한 해 동안의 분당서울대병원 환자의 데이터를 바탕으로 CDSS가 제안하는 추천과 실제 의료진에 의한 추천을 비교한 결과 78.9%의 일치율을 보였다. 불일치한 21.1%의 경우는 환자가 추천 치료를 받아들이지 않거나 수술이 변경된 경우이다. 본 연구를 통해 마인드맵과 IDT를 사용하는 지식 획득 방법의 우수성을 입증하였다.

헬스케어 빅데이터 유통을 위한 블록체인기술 활성화 방안

유형원,이은솔,고우균,한호성,한현욱,Yu, Hyeong Won,Lee, Eunsol,Kho, Wookyun,Han, Ho-seong,Han, Hyun Wook 한국빅데이터학회 2018 한국빅데이터학회 학회지 Vol.3 No.1

미래 의학의 핵심은 개인을 중심으로 한 정밀의료(Precision Medicine)의 실현이다. 이것이 가능하기 위해서는 헬스케어 데이터를 언제 어디서나 열람, 관리 및 유통 할 수 있는 개방형 생태계를 갖추어야 한다. 하지만, 헬스케어 데이터는 민감한 개인정보를 다루기 때문에 상당한 수준의 신뢰성과 보안성이 동시에 요구된다. 이를 해결하기 위한 방안으로 최근 의료계에서도 블록체인 기술에 주목하고 있다. 블록체인 기술은 거래정보를 중앙 서버에 저장 및 관리하는 기존의 정보통신 인프라와는 달리 유통되는 데이터를 네트워크에 참여하는 모든 사용자가 분산 및 관리하는 방식의 분산 운영망 이다. 본 연구에서는 블록체인 기술을 이용해 헬스케어 데이터 유통 실증에 필요한 기술적 및 법리적 제반 사항, 코렌(KOREN SDI)망 기반 헬스케어 빅데이터 유통 실증 연구의 소개 및 헬스케어 분야에서 블록체인 기술을 활성화하기 위한 정책적 전략에 대해 논의한다. At the core of future medicine is the realization of Precision Medicine centered on individuals. For this, we need to have an open ecosystem that can view, manage and distribute healthcare data anytime, anywhere. However, since healthcare data deals with sensitive personal information, a significant level of reliability and security are required at the same time. In order to solve this problem, the healthcare industry is paying attention to the blockchain technology. Unlike the existing information communication infrastructure, which stores and manages transaction information in a central server, the block chain technology is a distributed operating network in which a data is distributed and managed by all users participating in the network. In this study, we not only discuss the technical and legal aspects necessary for demonstration of healthcare data distribution using blockchain technology but also introduce KOREN SDI Network-based Healthcare Big Data Distribution Demonstration Study. In addition, we discuss policy strategies for activating blockchain technology in healthcare.

댐퍼를 갖는 복합구조 외팔보의 비틀림진동해석을 통한 접합부의 구조성능 평가

유형원,최낙삼 漢陽大學校 工學技術硏究所 1999 工學技術論文集 Vol.8 No.1

자동차의 크랭크축계 및 댐퍼풀리를 연구대상 모델로하여 댐퍼를 갖는 외팔보 복합구조물에 대한 자유 비틀림 진동특성을 검토하고 모델실험, 모달해석, 유한요소해석을 실시했다. 실험모델 구조물로는 금속 단일구조물, 금속/고무 복합구조물을 제작 사용했다. 결론적으로, 충격햄머를 이용한 자유진동실험을 통해 용접부와 기계적 체결부, 고무접착부의 강성과 감쇠계수를 1자유도법, 2자유도법, 3자유도법으로 평가할 수 있었다. Torsional free-vibration characteristics of a cantilever beam with damper have been studied using the theoretical and experimental modal analyses and a finite-element method. The torsional beam was made as a model of the crankshaft system with a damper pulley for motor car. Two kinds of model beams were used: simple metal beam and metal/rubber composite structure beam. Consequently, Stiffness and damping factor for weld, mechanical joint and adhered rubber layer could be evaluated using one-degree, two-degree, three-degree of freedom analyses through and impact hammer test.

Risk Factors of Postoperative Pancreatic Fistula in Curative Gastric Cancer Surgery

유형원,박도중,정두현,손상용,이창민,이주희,안상훈,김형호 대한위암학회 2013 Journal of gastric cancer Vol.13 No.3

Purpose: Postoperative pancreatic fistula is a dreadful complication after gastric cancer surgery. The purpose of this study is to evaluate the actual incidence and risk factors of postoperative pancreatic fistula after curative gastrectomy for gastric cancer. Materials and Methods: A total of 900 patients who underwent gastrectomy for gastric cancer (laparoscopic gastrectomy, 594 patients;open gastrectomy 306 patients) were enrolled between January 2009 and December 2010. Clinical outcomes, including postoperative pancreatic fistula grade based on the International Study Group on Pancreatic Fistula, were investigated. Results: Overall, the postoperative pancreatic fistula rate was 3.3% (30/900) (1.5% in laparoscopic gastrectomy versus 6.9% in open gastrectomy, P<0.001). Patients who underwent D2 lymphadenectomy, total gastrectomy, splenectomy or distal pancreatectomy showed higher postoperative pancreatic fistula rates (4.7%, 13.8%, 13.6%, or 57.1%, respectively, P<0.001). Patients with postoperative pancreatic fistula had higher morbidity (46.7% versus 13.1%, P<0.001), delayed gas out (4.9 days versus 3.8 days, P<0.001),belated diet start (5.8 days versus 3.5 days, P<0.001) and longer postoperative hospital stay (13.7 days versus 6.8 days, P<0.001). On the multivariate analysis, total gastrectomy (odds ratio 9.751, 95% confidence interval: 3.348 to 28.397, P<0.001), distal pancreatectomy (odds ratio 7.637, 95% confidence interval: 1.668 to 34.961, P=0.009) and open gastrectomy (odds ratio 2.934, 95%confidence interval: 1.100 to 7.826, P=0.032) were the independent risk factors of postoperative pancreatic fistula. Conclusions: Laparoscopic gastrectomy had an advantage over open gastrectomy in terms of the lower postoperative pancreatic fistula rate. Total gastrectomy and combined resection, such as distal pancreatectomy, should be performed carefully to minimize postoperative pancreatic fistula in gastric cancer surgery.

요한공동체의 여성신학

유형원 한국여신학자협의회 2003 한국여성신학 Vol.- No.53

점탄성층이 부분적으로 삽입된 샌드위치보의 횡진동 감쇠특성

박진택,유형원,장석원,최낙삼,Park, Jin-Taek,Yu, Hyeong-Won,Jang, Seok-Won,Choe, Nak-Sam 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.2

The flexural vibration characteristics of a sandwich beam system with a partially inserted viscoelastic layer have been quantitatively studied using a finite element analysis in combination with a sine-sweep test. Antisymmetric mode shapes of the flexural vibration were visualized by the holographic interferometry and agreed with those calculated by the finite element simulation. Effects of the beam thickness as well as the length and thickness of partial viscoelastic layers on the system loss factor(η$\_$s/) and resonant frequency($\omega$$\_$r/) were significantly large fur the symmetric and antisymmetric modes of the beam system.

A Study on the Contamination of D.I. Water and its Effect on Semiconductor Device Manufacturing

김흥식,유형원,윤철,김태각,최민성,Kim, Heung-Sik,Yoo, Hyung-Won,Youn Chul,Kim, Tae-Gak,Choi, Min-Sung The Institute of Electronics and Information Engin 1993 전자공학회논문지-A Vol.30 No.11

We analyzed the D.I. water used in wet cleaning process of semiconductor device manufacturing both at the D.I. water plant and at the wafer cleaning bath to detect the impurity source of D.I. water contamination. This shows that the quantity of impurity is related to the resistivity of D.I. water, and we found that the cleanliness of the wafer surface processed in D.I. water bath was affected by the degree of the ionic impurity contamination. So we evaluated the cleaning effect as different method for Fe ion, having the best adsoptivity on wafer surface. Moreover the temperature effect of the D.I. water is investigated in case of anion in order to remove the chemical residue after wet process. In addition to the control of D.I. water resistivity, chemical analysis of impurity control in D.I. water should be included and a suitable cleaning an drinsing method needs to be investigated for a high yielding semiconductor device.

Oncoplastic Thyroid Surgery Using A Bilateral Axillo-Breast Approach

성찬용,유형원,채영준,이규은 대한내시경복강경외과학회 2017 Journal of Minimally Invasive Surgery Vol.20 No.2

Since the first use of the robot da Vinci system for thyroid surgery in 2007, robotic thyroidectomy (RT) via a bilateral axillo-breast approach (BABA) has become a popular surgical alternative for patients who wish to avoid scars on the neck. BABA RT provides excellent cosmetic satisfaction with surgical safety and oncologic completeness. Recently, the use of BABA RT has expanded beyond benign thyroid nodules and small-sized papillary thyroid carcinoma (PTC) to Graves’ disease, relatively large PTCs, and PTC with lateral neck metastasis. Unfortunately, there are concerns about the use of this procedure for these additional indications. This review article summarizes postoperative outcomes of BABA RT for thyroid carcinoma, including quality of life, as well as expanding indications for BABA RT.

Prediction of Transient and Permanent Hypoparathyroidism after Total Thyroidectomy Using the Postoperative Serum Parathyroid Hormone Test: When Is the Best Time to Check?

김현주,유형원,배인의,이진욱,이준협,김수진,채영준,최준영,이규은 대한갑상선-내분비외과학회 2017 The Koreran journal of Endocrine Surgery Vol.17 No.3

Purpose The usefulness of serum intact parathyroid hormone (iPTH) levels for predicting hypocalcemia after total thyroidectomy is well established. This retrospective cohort study aimed to identify the best time iPTH levels should be checked, and determine the postoperative day 1 iPTH level that most safely predict the development of permanent hypoparathyroidism after total thyroidectomy. Methods All consecutive patients who underwent total thyroidectomy in 2013–2015 were identified, retrospectively. iPTH was measured at 2 hours after thyroidectomy, and on postoperative days 1 and 2, and 12 months after surgery. Results In total, 730 patients were included. Their iPTH levels on postoperative day 2 correlated better with postoperative day 1 levels (Pearson's r=0.915) than with iPTH levels at 2 hours after total thyroidectomy (r=0.786). Fourteen patients had normal iPTH levels at 2 hours after thyroidectomy but abnormal levels on postoperative days 1 and 2. On the other hand, 38 patients had abnormal iPTH levels at 2 hours after thyroidectomy but normal values on postoperative days 1 and 2. Receiver operating characteristic analysis showed that the iPTH value of 3.05 pg/mL best predicted permanent hypoparathyroidism (sensitivity, 92.9%; specificity, 99.7%). The safe cutoff value was 9.65 pg/mL (sensitivity, 70.9%; specificity, 100%). Conclusion A single measurement of iPTH on postoperative day 1 predicted patients at risk of transient hypocalcemia more accurately than measurements at 2 hours after surgery, and thus, can serve widely as a predictor of permanent hypoparathyroidism.

Isoflavonoid의 피부염증균에 대한 항균 및 항산화효과

신정미(Jung Mi Shin),유형원(Hung Won Yu),이현옥(Hyun Ok Lee),이미희(Mi Hee Lee),백승화(Seung Hwa Baek) 大韓藥學會 2006 약학회지 Vol.50 No.1

Puerarin and daidzin have been isolated from Puerariae thunbergiana Benth. Structures were determined by spectroscopic methods. Compounds showed weak antimicrobial activity against S. mutans, S. epidermidis, S. aureus, and C. albicans (MIC, 800㎍/㎖). However, these compounds were not antioxidative. Puerariae thunbergiana Benth. extracts against microorgani는 were evaluated in terms of the minimum inhibitory concentrations (MIC). In general, C. albicans was stronger antimicrobial activity than the other microorgani는. The antioxidative activity of was observed in the etyl acetate extract (IC50, 119.87±0.16㎍/㎖). The DPPH radical scavenging effect (IC50, 1,673.3±0.54μM) of the puerarin was comparable with that of synthetic antioxidant, BHA(IC50, 88.39±1.1)×10-3 μM. These results suggest that puerarin and daidzin have a potential antimicrobial activity.