노인의 거주형태에 따른 사망 위험요인: 동거노인과 독거노인의 비교

이시은,Lee, Si-Eun 한국디지털정책학회 2020 디지털융복합연구 Vol.18 No.9

본 연구의 목적은 노인의 거주형태에 따라 사망 위험요인에 차이가 있는지 파악하기 위함이다. 본 연구는 2014년도 고령화연구패널조사를 이차 분석한 연구로 노인 3,827명을 2년간 추적조사한 종단연구이다. 자료 분석을 위해 콕스 비례 위험 회귀 분석으로 분석하였다. 본 연구결과, 동거노인은 성별, 교육수준, 주관적 건강 상태, IADL 제한, 인지기능 장애, 우울 증상이 사망에 영향을 주는 요인이었으며, 독거노인은 규칙적 운동 여부, IADL 제한, 인지기능 장애가 사망에 영향을 주는 것으로 나타났다. 본 연구는 거주형태에 따라 사망 위험요인 간에 차이가 있는지 규명하였다는 점에서 의의가 있다. 본 연구 결과에 따라 노인의 거주형태에 따라 사망률을 줄이기 위한 간호 중재를 개발해야 할 것이다. This study was to identify differences in mortality risk by living arrangements among older adults. We analyzed data from 3,827 older adults who took part in the 2014 Korean Longitudinal Study of Aging. Cox proportional hazards regression was used for data analysis. The significant factors associated with mortality risk in living with others were male, education level, self-rated health, limitation of instrumental activities of daily living, cognitive dysfunction, and depression. The significant factors associated with mortality risk in living alone were regular exercise, limitation of instrumental activities of daily living, and cognitive dysfunction. This study is significant in that it examined whether there are differences between mortality risk by living arrangements. According to the results of this study, nursing intervention should be developed to decrease mortality by living arrangements.

수치해석 기법을 이용한 정밀선상성형장약의 성능 예측에 관한 연구

이시은,Lee, Sieun 한국군사과학기술학회 2022 한국군사과학기술학회지 Vol.25 No.3

Linear Shaped Charge(LSC) is widely used as a separation system in the field of weapon system. However, there are some disadvantages that are charging lots of explosives due to lack of uniformity and having difficulties of the design of liner and explosives because of manufacturing process. In order to solve these problems, Precision Linear Shaped Charge(PLSC) that can design a liner independently and charge explosives uniformly has been developed. In this study, PLSC was designed to have a proper liner shape and amount of explosives, and the penetration test of PLSC with different stand-off distance from liner to target was conducted. On the basis of the penetration test results of PLSC, the numerical analysis method using AUTODYN was established and verified. The penetrative mechanism and characteristics of PLSC with targets of different materials was analyzed from experimental and numerical results.

CAD/CAM system을 이용한 하악 임플란트 피개의치 수복증례

이시은,이소현,전영찬,정창모,윤미정,허중보,Lee, Si-Eun,Lee, So-Hyoun,Jeon, Young-Chan,Jeong, Chang-Mo,Yun, Mi-Jung,Huh, Jung-Bo 대한치과보철학회 2015 대한치과보철학회지 Vol.53 No.1

Alveolar bone loss and deformation can be a risk factor in removable prosthetic restoration treatment for partially or fully edentulous patients. The use of implants to solve this problem could improve the support, retention and stability of removable restoration. Attachments used in implant overdenture are versatile. The attachment should be selected according to the patients' conditions. Milled bar has been chosen when readymade bar could not be used because of the narrow distance between implants or firm stability and support of supra-structure were needed. Milled bar design is able to provide cross arch stabilization and comfortability to patients. However, it needs skilled laboratory procedures. Recently, the fabrication of milled bar has become simple and its suitability has been improved through the development of CAD/CAM system. In a 67-year-old female Alzheimer's disease patient with 8 implant fixtures on the fully edentulous site of mandible, implant overdenture with using milled bar and magnet attachment was planned. As rapid treatment was required, CAD/CAM system was used to make a simple laboratory procedure instead of a traditional fabrication process. With this system, implant overdenture with milled bar can be fabricated esthetically and functionally. 완전, 혹은 부분 무치악 환자의 가철성 보철물 수복치료에서 치아 상실에 따른 치조골 감소와 별형은 의치 사용에 어려움을 준다. 이런 문제를 극복하기 위해 임플란트를 이용하여 가철성 보철물에 지지, 유지, 및 안정을 제공할 수 있다. 임플란트를 이용한 피개의치에 사용되는 어태치먼트는 여러 종류가 있는데, 환자의 여러 조건을 고려하여 어태치먼트를 선택해야 한다. 그 중 milled bar의 경우 임플란트 간 거리가 좁아서 기성 bar를 사용할 수 없는 경우, 또는 기성 bar보다 상부 구조물의 확고한 안정성과 지지를 얻고자 할 때 선택 된다. Milled bar는 cross arch stabilization을 이룰 수 있고, 저작 시 의치의 움직임이 없어 환자에게 편안함을 제공하지만, 숙련된 기공과정을 요한다. 그러나 최근 CAD/CAM의 발전을 통해 milled bar의 제작이 간결해지고 적합성을 증진시킬 수 있었다. 본 증례는 8개의 임플란트가 식립된 하악 완전 무치악의 알츠하이머 환자로 milled bar와 magnet을 이용한 피개의치를 제작하였다. 전신병력이 양호해진 기간 동안 빠른 치료종결이 필요했기 때문에, 통법의 기공 작업을 CAD를 통해 시뮬레이션하여 복잡한 기공과정을 좀더 단순하게 하였고 이로써 치료 기간을 줄일 수 있었다. 이상과 같이 milled bar를 이용한 임플란트 지지 피개의치를 제작하는 과정 중 CAD/CAM system을 적절히 사용하여 심미적, 기능적으로 만족할 만한 결과를 얻었기에 보고하고자 한다.

지역사회 거주 노인의 주관적 연령 관련 요인

이시은,Lee, Si-Eun 한국디지털정책학회 2020 디지털융복합연구 Vol.18 No.9

본 연구의 목적은 한국 지역사회 거주 노인의 주관적 연령과 관련된 요인을 규명하는 것이다. 본 연구는 2017년도 노인실태조사에 참여한 65세 이상 노인 8,040명을 대상으로 이차 분석한 횡단 연구이다. 노인의 주관적 연령과 관련된 요인을 규명하기 위해 단변량 로지스틱 회귀분석에서 유의한 변수만 추출하여 다변량 로지스틱 회귀분석으로 분석하였다. 본 연구결과, 성별, 학력, 거주형태, IADL 제한, 만성질환 수, 지각된 건강 상태, 우울 및 현재 경제활동 여부가 노인의 주관적 연령과 관련이 있는 것으로 나타났다. 본 연구결과에 근거하여 주관적 연령을 낮추기 위한 간호중재가 이루어져야 할 것이다. 본 연구를 통해 노인들이 건강하고 성공적인 노후를 보내는 데 기여할 수 있을 것이다. The purpose of this study was to identify the factors associated with subjective age among community-dwelling older adults in South Korea. Cross-sectional analyses were performed on 8,040 older adults aged 65 years and over from the 2017 National Survey of Older Koreans. We used univariable analysis and multivariable analysis by the logistic regression test. The significant factors associated with subjective age in older adults were gender, education level, living arrangements, limitation of instrumental activities of daily living, number of chronic diseases, perceived health status, depression, and current economic activity. Based on the results of this study, nursing intervention will be needed to lower subjective age. This study may contribute to the older adults to have a healthy and successful old age.

Differing benefits of artificial intelligence-based computer-aided diagnosis for breast US according to workflow and experience level

이시은,Han Kyung Hwa,육지현,Lee Jee Eun,Hwang Ji-Young,노미리비,Yoon Jiyoung,김은경,윤정현 대한초음파의학회 2022 ULTRASONOGRAPHY Vol.41 No.4

Purpose: This study evaluated how artificial intelligence-based computer-assisted diagnosis (AICAD) for breast ultrasonography (US) influences diagnostic performance and agreement between radiologists with varying experience levels in different workflows. Methods: Images of 492 breast lesions (200 malignant and 292 benign masses) in 472 women taken from April 2017 to June 2018 were included. Six radiologists (three inexperienced [<1 year of experience] and three experienced [10-15 years of experience]) individually reviewed US images with and without the aid of AI-CAD, first sequentially and then simultaneously. Diagnostic performance and interobserver agreement were calculated and compared between radiologists and AI-CAD. Results: After implementing AI-CAD, the specificity, positive predictive value (PPV), and accuracy significantly improved, regardless of experience and workflow (all P<0.001, respectively). The overall area under the receiver operating characteristic curve significantly increased in simultaneous reading, but only for inexperienced radiologists. The agreement for Breast Imaging Reporting and Database System (BI-RADS) descriptors generally increased when AI-CAD was used (κ=0.29-0.63 to 0.35-0.73). Inexperienced radiologists tended to concede to AI-CAD results more easily than experienced radiologists, especially in simultaneous reading (P<0.001). The conversion rates for final assessment changes from BI-RADS 2 or 3 to BI-RADS higher than 4a or vice versa were also significantly higher in simultaneous reading than sequential reading (overall, 15.8% and 6.2%, respectively; P<0.001) for both inexperienced and experienced radiologists. Conclusion: Using AI-CAD to interpret breast US improved the specificity, PPV, and accuracy of radiologists regardless of experience level. AI-CAD may work better in simultaneous reading to improve diagnostic performance and agreement between radiologists, especially for inexperienced radiologists.

고분자 복합재의 물리화학적 및 전자파차폐 특성에 미치는 탄소나노튜브의 불소화 영향

이시은(Si-Eun Lee),김도영(Doyoung Kim),이만영(Man Young Lee),이민경(Min-Kyung Lee),정의경(Euigyung Jeong),이영석(Young-Seak Lee) 한국고분자학회 2015 폴리머 Vol.39 No.1

탄소나노튜브의 불순물을 제거하고 에폭시 수지와의 계면접착력 향상과 에폭시 내 탄소나노튜브의 분산성 증가를 위하여 불산(hydrofluoric acid)으로 그 표면을 개질하였다. 표면 처리된 탄소나노튜브의 결정성은 광전자 분광기(X-ray photoelectron spectroscopy)와 라만 분광기(Raman spectroscopy)를 통해 분석하였고, 인장시험으로 기계적 강도 분석을 실시하였다. 표면 처리된 탄소나노튜브/에폭시 복합재의 인장강도는 미처리 탄소나노튜브/에폭시 복합재와 비교하여 최대 약 33% 향상됨을 확인할 수 있었고, 탄소나노튜브/에폭시 복합재의 전자파차폐 특성은 탄소나노튜브의 불산처리 농도에 따라 증가하는 경향을 보였고 25%의 농도로 처리되었을 때, 최대 전자파차폐 특성을 보였다. 그러나 기계적 특성 및 전자파차폐 특성은 50% 이상의 불산 농도로 처리된 탄소나노튜브/에폭시 복합재에서 오히려 감소하였으며 이는 높은 농도의 불산으로 인하여 탄소나노튜브의 표면 결정성 감소 및 고유 특성에 영향을 미친 것으로 파악된다. 고분자 복합재의 기계적, 전기적 특성 향상은 불산 처리로 인한 탄소나노튜브의 결정성 향상과 에폭시 수지 내에 분산성의 증가에 기인하였다. Mutli-walled carbon nanotubes (MWCNTs) were surface-modified by a hydrofluoric acid solution to remove impurities and improve interfacial bonding and dispersion of nanotubes in an epoxy matrix. The crystallinity on the surface of treated MWCNTs was investigated by X-ray photoelectron spectroscopy and Raman spectroscopy. The mechanical properties were characterized by tensile test, and the enhancement of mechanical properties of the modified MWCNTs/epoxy composites was indicated by a 33% increase in tensile strength. The electromagnetic interference shielding effectiveness (EMI-SE) of modified MWCNTs/epoxy composites was improved with an increase in concentration of hydrofluoric solution, and EMI-SE showed the maximum increase with 25% HF. However, mechanical and EMI-SE properties didn’t show further increase with over 50% HF concentration because the properties of MWCNTs were influenced by degradation of crystallinity and intrinsic properties of MWCNTs. The mechanical and electrical property enhancements of the polymer composites are attributed to the modification of MWCNTs which improve crystallinity of MWCNTs and dispersion in the epoxy resin.

폴리에테르설폰이 도입된 에폭시 복합재의 열 안정성 및 기계적 특성

이시은(Si-Eun Lee),박미선(Mi-Seon Park),정의경(Euigyung Jeong),이만영(Man Young Lee),이민경(Min-Kyung Lee),이영석(Young-Seak Lee) 한국고분자학회 2015 폴리머 Vol.39 No.3

Poly(ether sulfone) (PES)가 첨가된 비스페놀-A 에폭시 복합재가 그 기계적 특성 및 열 안정성을 증진하기 위하여 제조되었다. 인장강도, 굽힘강도 및 충격강도 등의 기계적 강도가 PES 함량에 따라 의미있게 변화하였다. 특히 그 파괴인성 값은 약 24%의 정도 크게 향상되었다. 적분 열분해 진행온도를 통하여 계산된 PES/에폭시 복합재의 열 안정성은 PES 미첨가 에폭시와 비교하여 12%의 향상을 보였다. 또한 DSC 분석 결과 PES 함량이 증가함에 따라 경화온도와 경화열이 점점 감소함을 확인하였다. 이러한 현상은 에폭시 수지와 선형 PES가 가교구조(semiinterpenetrating polymer networks; semi-IPNs)를 형성하고 잘 분산되었기 때문으로 판단된다. Poly(ether sulfone) (PES) embedded diglycidylether of bisphenol-A (DGEBA) epoxy composites were fabricated for improving its mechanical properties and thermal stability. The mechanical properties such as tensile, flexural and impact strength of the composites changed significantly with the introduction of PES. The value of the fracture toughness of this composite also was increased remarkably about 24%. Thermal stability of PES/epoxy composites also improved 12%, which was calculated with integral procedural decomposition temperature (IPDT). From the differential scanning calorimeter (DSC) result, the curing temperature and curing heat decreased according to the increase of PES contents. These were attributed to the good distribution and the formation of the semi-interpenetrating polymer networks (semi-IPNs) composed of the epoxy network and linear PES.

Left pneumonectomy using self-cutting linear endoscopic stapler in a dog

이시은(Si Eun Lee),박효진(Hyojin Park),이채영(Chae-Yeong Lee),최현종(Hyeon-Jong Choi),김효연(Hyoyeon Kim),김민연(Minyeon Kim),홍정호(Jeongho Hong),유도현(DoHyeon Yu),황태성(Tae Sung Hwang),이희천(Hee Chun Lee),이재훈(Jae-Hoon Lee),이동 한국예방수의학회 2021 예방수의학회지 Vol.45 No.4

A 13-year-old mixed dog was referred to the animal medical center, Gyeongsang National University. Lung masses were diagnosed at the left cranial and caudal lobes through diagnostic imaging, and consequently, left pneumonectomy was performed using a self-cutting linear endoscopic stapler. The pulmonary arteries, veins, and bronchus of each lung lobe were sealed and resected at once, and any air leakage or bleeding was not observed after the surgery. Compared to the conventional ligation method, the self-cutting linear endoscopic stapler has the advantage of significantly reducing the operation time and enabling simple and reliable sealing.

Characteristics of Ammonia Emissions and Fine Secondary Particulate Matter Formation from Livestock Manure Compost Applications in Paddy Soil

Ju-Hee Lee(이주희),Seoung-Woo Choi(최성우),Do-Hyeong Lee(이도형),Yeo-Myeong Lee(이여명),Si-Eun Lee(이시은),Sang Yoon Kim(김상윤) 한국토양비료학회 2019 한국토양비료학회 학술발표회 초록집 Vol.2019 No.8

The Impacts of Different Ammonium-Based Fertilizers on Greenhouse Gas Intensity and Lettuce Productivity in Upland Soils during Cultivation

Ju-Hee Lee(이주희),Yeo-Myeong Lee(이여명),Si-Eun Lee(이시은),Seoung-Woo Choi(최성우),Do-Hyeong Lee(이도형),Sang Yoon Kim(김상윤) 한국토양비료학회 2019 한국토양비료학회 학술발표회 초록집 Vol.2019 No.8