척추측만증 환자의 수술 효과 평가 수단으로서 웨어러블 스마트 깔창을 이용한 보행분석의 유용성

서민석,신명준,권애란,박태성,남경협 중소기업융합학회 2020 융합정보논문지 Vol.10 No.2

This study presents a gait analysis method (including time series analysis) using a smart insole as an objective and quantitative evaluating method after lumbar scoliosis surgery. The participant is a degenerative lumbar scoliosis patient. She took 3-min-gait-test four times(before and 8, 16, and 204-days after surgery) and 6-min-gait-test once(204-days after surgery) with smart-insoles in her shoes. Each insole has 8-pressure sensors, an accelerometer, and a gyroscope. The measured values were used to compare the characteristics of gait before and after surgery. The analysis showed that all of the patient's gait parameters improved after surgery. And after 6 months, the gait was more stable. However, after long walk, the swing duration of one leg was slightly shorter than that of the other again. It was a preclinical problem that could not be found in the visual examination by the practitioner. With this analysis method we could evaluate the improvement of patient quantitatively and objectively. And we could find a preclinical problem. This analysis method will lead to the studies that define and distinguish gait patterns of certain diseases, helping to determine appropriate treatments. 본 연구는 척추측만증 수술에 대한 객관적이고 정량적인 효과 평가 수단으로서 스마트 깔창을 이용한 보행분석 방법(시계열 분석 포함)을 제시한다. 실험 참가자는 척추측만증 환자이며 스마트 깔창을 착용하고 3분 보행검사를 4번(수술전, 수술 후 8일, 16일, 204일), 6분 보행검사를 1번(수술 후 204일) 받았다. 깔창에는 8개의 압력센서, 가속도 및 각속도 센서가 있고, 각각의 측정값을 저장하여 환자의 수술 전후 보행특성(운동역학 및 시공간 변수)을 비교하였다. 분석결과 수술 후 환자의 모든 보행 변수가 개선된 것을 알 수 있었고, 6개월 후 추적검사에서 환자의 보행이 더욱 안정된 것을 확인할 수 있었다. 하지만 환자가 오래 걸으면 한쪽 다리의 swing 시간이 다른 쪽에 비해 미세하게 짧은 현상이 다시 나타났는데, 이는 검사를 수행하는 의사의 육안으로는 발견할 수 없는 preclinical한 문제였다. 우리는 이러한 분석 방법을 통해 환자의 개선 정도를 정량적이고 객관적으로 평가할 수 있었고, preclinical한 문제도 찾을 수 있었다. 향후 이러한 분석 방법은 특정 질병의 보행 패턴을 정의하고 감별하여 적절한 치료방법을 결정하는 연구로 이어질 것이다.

Sn-Bi 합금도금층의 미세조직에 미치는 도금변수의 영향 및 Sn-Bi/Cu계면에서의 금속간 화합물의 성장

徐敏碩,朴燦鎭,權赫尙 대한금속재료학회 2002 대한금속·재료학회지 Vol.40 No.1

Alloy deposits of Sn-Bi, were electroplated on a Cu plate from an organic sulfonate bath using direct or pulsed currents, and the effects of the plating parameters on the composition and the microstructure of the electrodeposits were investigated. In addition, the effects of alloy composition of the electrodeposits on the formation kinetics of intermetallic compounds were examined. Addition of grain refiner to the bath increased the cathodic polarization, and reduced the difference of the deposit potential between Sn and Bi. Thus, Sn-Bi alloy can be electrodeposited with fine and rounded grains in bath with the additive. The Sn content in the deposits was increased with an increase of Sn content in the bath. The preferred deposition trend of Sn was stronger than that of Bi, because the deposit potential of Sn was more positive than that of Bi in the bath with the additive. The Sn content in the deposits was decreased with an increase of current density, and the grains of deposit became finer because of the increased cathodic overpotential. When Sn-Bi alloy was electrodeposited using pulse current at 4 A/d㎡ peak current density, the Sn content in the deposit was increased with increasing the pulse frequency and decreasing the duty cycle. The morphology of Sn-Bi deposits became finer with decreasing pulse frequency and increasing duty cycle. When the depostis of Sn-Bi alloy were aged at 80℃, the growth of Cu-Sn intermetallic compound layer [ε(Cu_3Sn) +η'(Cu_6Sn_5)] showed a parabolic time dependence, and the growth rate of that depended significantly on the composition of Sn-Bi electrodeposits. The apparent activation energy for the growth of intermetallic compound in 42Sn-58Bi electrodeposit was 52.48 kJ/㏖, that in 70Sn-30Bi elecrodeposit was 43.32 kJ/㏖, and that in 90Sn-10Bi was 41.35 kJ/mol.

착용(Wear)에서 동반(Company)으로의 진화, 그리고 서비스화(Servitization)

서민석 대한산업공학회 2014 ie 매거진 Vol.21 No.3

Multidisciplinary Team Approach in Prostate-Specific Membrane Antigen Theranostics for Prostate Cancer: A Narrative Review

서민석,천기정 대한비뇨기종양학회 2024 대한비뇨기종양학회지 Vol.22 No.1

In managing prostate cancer, the integration of multidisciplinary team (MDT) with prostate-specific membrane antigen (PSMA) theranostics marks a significant advancement, addressing the disease's spectrum from indolent forms to aggressive metastatic stages. MDTs, comprising urology, oncology, radiation oncology, pathology, radiology, and nuclear medicine experts, are pivotal in delivering tailored, evidence-based care, essential for the varied clinical presentations of prostate cancer. The introduction of PSMA-targeted theranostics and PSMA positron emission tomography imaging has impacted the approach to diagnosis and treatment, offering enhanced precision in disease localization and enabling more nuanced management strategies for conditions such as oligometastatic prostate cancer, metastatic hormone-sensitive prostate cancer, and metastatic castration-resistant prostate cancer. The collaborative approach of MDTs in utilizing PSMA-targeted radioligand therapy emphasizes meticulous patient selection, predictive assessment of therapy response, and careful management of therapy-related toxicities. Additionally, recent strategies, including combination therapies from ENZA-P and Lu-PARP trials, show potential for improving treatment efficacy. This unified approach showcases the critical role of MDTs in optimizing treatment outcomes, underscoring the importance of collaboration in advancing the treatment of prostate cancer with PSMAtargeted therapies, thereby setting a new paradigm in personalized prostate cancer management.

Temperature Effects of Side Chains on Poly (Υ-alkyl a, L-glutamate)

서민석,손대원 한국고분자학회 1998 한국고분자학회 학술대회 연구논문 초록집 Vol.1998 No.10

풍납토성 성벽 토양의 성분 특성 연구

서민석,이한형,허준수,김수경,유영미,이성준 국립문화재연구원 2012 헤리티지:역사와 과학 Vol.45 No.4

The purpose of this study is to analysis chromaticity, granulometry, main chemical composition and mineral crystal structure of wall soils excavated from Poongnatoseong Earthen Castle using color reader, XRD, particla size analyzer. The analysed soils of Poongnatoseong Earthen Castle were yellowish brown and isabella. All samples were sands or sands including silty soil(SW~SC) and showed similar granulometry, chemical composition and mineral crystal structure, which were characteristics of construction materials suitable for modern road or airstrip. As resulting in comparison with 4 factors from chromaticity, granulometry, main chemical composition and mineral crystal structure, we decided that the control soils(PNS) near by Poongnatoseong Earthen Castle were not to be used for the castle wall construction We presumed that there was a huge soil distribution area for the wall construction around Poongnatoseong Earthen Castle. For further study, we will make a comparison analysis all kinds of soil characteristics. And then we can understand correctly about wall soils producing area, construction method, repair method and time of Poongnatoseong Earthen Castle. 본 연구에서는 풍납토성 동성벽 내부토양을 대상으로 색도색차계, XRD, 입도분석기 등을 이용하여 색도, 입도, 주요화학조 성, 광물결정구조 등을 분석하였다. 성벽토양은 황갈색, 회황색의 모래 또는 실트질 모래(SW~SC)로 분류되고, 입도와 화학ㆍ 광물학적 특성이 유사하며, 도로나 활주로 등의 성토재료로 적합한 특성임이 확인되었다. 색도, 입도, 화학조성, 강열감량의 4인 자를 기준으로 비교분석한 결과, 풍납토성이 위치한 지역의 대조군 토양(PNS)은 성벽축조에 사용되지 않았던 것으로 판단한다. 모든 토양은 풍납토성이 위치한 지역과 지질학적으로 유사한 곳에서 채굴되었던 것으로 추정되지만, 성벽 축조 이전에 분포했 던 구지표면의 토양과는 다른 특성을 나타내기 때문에, 유적 주변에 대량채굴이 가능했던 토양분포지가 존재할 것으로 추정된 다. 향후 성벽 축조재료의 여러 특성들을 비교ㆍ분석하면, 성벽 내부토양의 산지, 축조방법, 보수방법 및 시기 등을 보다 종합적 으로 이해할 수 있는 계기가 마련될 것으로 기대한다.

500MPa 벽체전단철근의 최소철근량에 대한 실험적 연구

서민석,최경규,박홍근 대한건축학회 2016 大韓建築學會論文集 : 構造系 Vol.32 No.8

In the present study, experimental investigations were performed on nine reinforced concrete walls with a shear span to wall height ratio of 2.5 and rectangular cross sections under cyclic lateral loading. The major test parameters were the grade of shear re-bar (400MPa and 500MPa), concrete compressive strength (24MPa and 35MPa), axial load ratio (0% and 20%), failure mode (shear failure before or after flexural yielding), and horizontal shear reinforcement details (double layer and single layer). Based on the test results, the structural performances and characteristics of test specimens were investigated in terms of load-carrying capacity (shear or flexural strength), hysteretic behavior, strain distribution, lateral displacement component, and energy dissipation capacity. The test results of specimens designed to be failed in shear before flexural yielding showed that seismic performances of the walls with 500MPa re-bars (20% reduction in shear reinforcement) were almost identical to that of the walls with 400MPa re-bars. For specimens designed to be failed after flexural yielding, the specimen with single layered shear reinforcement showed almost identical strength and greater drift capacity compared to those of the specimen with double layered shear reinforcement.

구리계 리드프레임 합금에 전착된 Sn-Pb합금의 시효처리가 Cu-Sn 금속간화합물의 성장속도와 도금층의 파괴에 미치는 영향

서민석,권혁상 한국표면공학회 1995 한국표면공학회 학술발표회 초록집 Vol.1995 No.-

유기 슬폰화욕에서 Sn-Bi합금 도금조건이 도금층의 조성에 미치는 영향

서민석,권혁상 한국표면공학회 1997 한국표면공학회 학술발표회 초록집 Vol.1997 No.-

크롤러형 굴삭기의 동역학적 모델 개발 및 시뮬레이션

서민석,김형근 한국자동차공학회 1995 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1995 No.11_1