슬관절 등속성 운동시 근골격 모델의 검증:실험 및 모의실험 연구 : 실험 및 모의실험 연구 An Experimental and Simulatio study

배태수,강성재,최경주,김신기,유재욱,진미령,문무성 대한정형외과연구학회 2003 대한정형외과연구학회지 Vol.6 No.2

구형압입시험을 통한 망상골의 기계적 물성 연구

배태수,김정규,이태수,최귀원 대한의용생체공학회 2001 의공학회지 Vol.22 No.5

골다공증의 조기 발견 및 치료예후에도 영향을 미치는 망상골 구조의 영률(Young's Modulus)은 그 대상이 사람이므로 일반적인 인장 및 압축시험으로 구해내기는 불가능한 실정이다. 본 연구에서는 망상골 구조가 지니고 있는 영률을 평가함에 있어서 구형압입시험을 통하여 망상골 구조의 영률을 구하고자 하였으며 이를 전산화단층촬영(CT)에서부터 얻을 수 있는 밀도와 실제 측정해서 얻은 밀도와의 관계를 정량화하고자 한다. 31세 남성의 좌우 원위 대퇴골을 해부학적 좌표를 고려하여 고정한 다음 GE9800 CT장비를 사용하여 Imm간격으로 단층촬영을 실시하였으며. 각 영상으로부터 CT수(HU)를 구하였다 Dliamond saw를 사용하여 좌우 대퇴골으로부터 72개의 8mm 정방형 시편들을 추출하였으며. 제작한 구형압입시험기를 사용하여 각 시편의 IS. AP. 그리고 ML방향으로의 압입시험과 압축시험을 각각 실시하였으며, 이후 시편의 실제 겉보기 밀도를 측정하였다. 그 결과 IS방향의 영률이 AP 및 ML방향보다 유의하게 크게 나타났으며, AP방향의 영률 역시 ML방향보다 유의하게 큰 영률을 나타냄을 통하여 망상골의 직교성을 알 수 있었다. CT수와 각 방향의 영률과의 관계에서도 선형적 관계보다는 멱관계로 보다 더 잘 설명되어짐을 알 수 있었는데 이는 이전의 연구자들과 동일한 결과임을 알 수 있었다 We intended to evaluate the Young's modulus of trabecular bone of a human distal femur by spherical Indentation test and CT images and to quantify relationships between the direction of load, density. and Young's modulus. The specimens were scanned at 1 mm intervals on CT scanner After scanning the bones were sectioned with diamond saw. producing 8mm cubes of trabecular bone. The tubes were mechanically tested in inferior-superior(IS), anterior-posterior(AP). and medial-lateral(ML) direction with custom-made device. After testing, the real apparent density of specimens were measured. The results of this study showed that the IS modulus was significant1y greater than both the AP and ML modulus and the AP modulus was also greater than ML modulus significantly(p〈0.01) A significant Power relationship between the apparent density and the modulus was also found.

원자/분자에 관한 고등학교 학생과 과학교사의 오인 분석

裵泰洙,崔秉舜 한국교원대학교 과학교육연구소 1991 청람과학교육연구논총 Vol.1 No.1

이 연구는 화학분야의 기본 개념인 원자/분자에 관한 오인을 밝히기 위해서 중학교 2학년 단원의 원자/분자에 관한 개념을 중심으로 15문항을 개발하여 중ㆍ고등학생을 대상으로 지필검사를 실시하였다. 연구결과에 의하면, 학습 유무, 학년, 성별에 따라 오인 정도가 다른 것으로 밝혀졌다. 동일 문항을 이용하여 교사들의 오인이 어느 정도인가를 알아본 결과에 의하면 거의 올바른 개념을 가지고 있었으나 문항의 내용에 따라서 교사의 전공별로는 어느 정도의 오인이 존재함을 알 수 있었다. 그리고, 학생들의 인지 수준과 오인과의 관계를 분석한 결과에 의하면 학년, 성별에 관계없이 인지수준이 높을 수록 올바른 과학적 개념을 더 많이 형성하고 있음을 알 수 있었다. It is very important to know what the student's ideas in science is in learning scientific concepts. According to previous studies learner's cognitive structure is not tabula-rasa but has his own conceptual framework before formal science teaching and learning. Therefore, it is nessasary to search whether the student's ideas in science is different from scientific knowledge or not. The purpose of this study was to search for misconception on atoms and molecules of secondary school students and science teachers. Also the relation-ships between student's misconception and their subvariables such as sex, grade, and cognitive level were sought. The population of the study consisted of 800 students and 114 science teachers. Statistical analysis of obtained data was run by spss/pc^(+)program.

A Comparative Study of the Methods for Measuring Lumbar Intervertebral Gap Using Radiographic Images

배태수,고철웅,박희수 한국정밀공학회 2016 International Journal of Precision Engineering and Vol.17 No.6

Anterior and posterior intervertebral gap of lumbar spine is important when developing the spinal implants regarding lumbar system. However, the measuring methods continue to be still controversial because of the absence of a standardized measurement. The objective of this study is to propose novel methods of measuring lumbar intervertebral gap and to conduct comparative analysis with other measuring methods. We took the lateral radiography images of 20 males taking the postures of supine, seat and standup. The anterior intervertebral gap and posterior intervertebral gap were measured with three different methods and two pre-existing methods. The comparison of results from three different measuring methods and two pre-existing methods showed that the difference at the anterior intervertebral gap was mostly statistically significant. This study suggests that it is necessary to consider the clinical meaning of the difference among measuring methods in order to establish a database to fabricate spine implants and to make efforts to improve measuring methods in the future.

A Musculoskeletal Model for Biomechanical Analysis of Transfemoral Amputees Climbing Stairs

배태수,김신기,문무성 한국정밀공학회 2008 International Journal of Precision Engineering and Vol.9 No.1

Understanding the characteristics of amputee gait is key in developing more advanced prostheses. The aim of this study was to quantitatively analyze a stair-climbing task for transfemoral amputees with a prosthesis and to predict the muscle forces and joint moments at musculoskeletal joints using a dynamic analysis. A three-dimensional musculoskeletal model of the lower extremities was constructed from a gait analysis using transformation software for two transfemoral amputees and ten healthy people. The measured ground reaction forces and kinematical data of each joint from the gait analysis were used as input data for an inverse dynamic analysis. Dynamic analyses of an transfemoral amputee climbing stairs were performed using musculoskeletal models. The results showed that the summed muscle forces of the hip extensor of an amputated leg were greater than those of a sound leg. The opposite was true at the hip abductor and knee flexor of an amputated leg. We also found that higher moments at the hip and knee joints of the sound leg were required to overcome the flexion moment caused by the body weight and amputated leg. Dynamic analyses using musculoskeletal models may be a useful means to predict muscle forces and joint moments for specific motion tasks related to rehabilitation therapy.

Effect of fin length and shape of stemless humeral components in a reverse shoulder implant system: a FEA study

배태수,Erin E. Ritzer,Woong Cho,Won Joo 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.1

The recent reverse total shoulder arthroplasty (TSA) implant designs employ shorter humeral component stems; some designs even eliminate the stem completely. The short stem provides several advantages: preserved bone, less stress shielding, ease of revision surgery, and freedom of humeral component location due to the minimal stem length and noncomplex shape. However, due to the reduction in contact surface and frictional fixation, this stemless design may cause failure of the implant, especially during early stages following surgery. In this study, the effect of fin shape and fin length of stemless humeral components were investigated, and hypothesis was that stress and micromotion would decrease as the ratio of fin length to baseplate radius increases and the overall size of the humerus component increased. 15 different 3D models of stemless humeral components, 5 different lengths and 3 different shapes, within reverse TSA systems were developed. Each humerus component was analyzed using finite element analysis (FEA) to investigate the effects of stem length and fin shape on the initial stability of the component. The highest stress and micromotion were observed at the shortest fin length; lowest stress and micromotion were found at the longest fin length. Results suggest that the length of the fin affects the stress at the bone as well as the amount of micromotion; 20-30 % longer fin length than baseplate radius would be ideal for the stemless humeral component design. However, the various fin shapes showed mixed effects on the results and further investigation is required.

다채널 진동자극이 상지절단자 체성감각에 미치는 영향

배태수(T. S. Bae),김형재(H. J. Kim),김솔비(S.B. Kim),장윤희(Y.H. Chang),김신기(S.K. Kim),문무성(M. S. Mun) 한국정밀공학회 2011 한국정밀공학회 학술발표대회 논문집 Vol.2011 No.6월

근골격 모델을 이용한 대퇴절단환자의 계단보행에 대한 동역학 해석

배태수(Tae Soo Bae),김신기(Shin Ki Kim),문무성(Mu Seong Mun) Korean Society for Precision Engineering 2007 한국정밀공학회지 Vol.24 No.7

It is important to understand the characteristics of amputee gait to develop more advanced prostheses. The aim of this study was quantitatively to analyze the stair climbing task for the above-knee amputee with a prosthesis and to predict muscle forces and joint moments at musculoskeletal joints by dynamic analysis. The three-dimensional musculoskeletal model of lower extremities was constructed by gait analysis and transformation software for one above-knee amputee and ten healthy people. The measured ground reaction forces and kinematical data of each joint by gait analysis were used as input data during inverse dynamic analysis. Lastly, dynamic analysis of above-knee amputee during stair climbing were performed using musculoskeletal models. The results showed that summed muscle forces of hip extensor of amputated leg were greater than those of sound leg but the opposite results were revealed at hip abductor and knee flexor of amputated leg. We could also find that the higher moments at hip and knee joint of sound leg were needed to overcome the flexion moment caused by body weight and amputated leg. In conclusion, dynamic analysis using musculoskeletal models may be a useful mean to predict muscle forces and joint moments for specific motion tasks related to rehabilitation therapy.

무릎관절에서의 단계별 도수견인에 따른 견인력과 연성변이와의 관계

배태수(Tae Soo Bae),허현(Hyun Heo),김경훈(Kyung Hun Kim),안재용(Jae Yong Ahn) Korean Society for Precision Engineering 2008 한국정밀공학회지 Vol.25 No.4

Although manual traction, one of pain therapies, was applied in clinic to relief pain, the study was rare on the manual force and displacement of ligaments at knee joint during manual traction. The aim of this study is to quantify not only manual force at knee joint but also elongated displacement of joint ligament by C-arm scanning and motion analysis. Twenty-one healthy subjects were tested with manual traction from grade Ⅰ to grade Ⅲ under neutral position by a physical therapist. We calculated traction force using joint forces of both hands and elongated displacement of joint ligament were measured. The results showed that traction forces by C-arm scanning analysis were averagely 1.67-fold greater than those by motion analysis, but elongated displacements were instead averagely 2.36-fold smaller than motion analysis. Finally, we could estimate relationship between traction force and elongated displacement at knee joint by two methods.

Evaluation of Joint Load as Pre-Operative Traction in Fracture Reduction Surgeries of Femur and Tibia

배태수(Tae Soo Bae),조병찬(Byeong Chan Cho),한재웅(Jae Woong Han) Korean Society for Precision Engineering 2019 한국정밀공학회지 Vol.36 No.10

Safe pre-operative traction applied and maintained to the fractured site in fracture reduction surgery is crucial. However, existing traction techniques performed by clinicians or manual traction devices are not elaborate and have no traction force information considering differences in patients’ bodies. The purpose of this study was to evaluate joint loads of fractured sites as pre-operative traction forces considering body mass index (BMI) during fracture reduction surgeries using a robotassisted device. We developed a lower-extremity dummy model to measure joint loads at hip, knee, ankle, and fractured sites. In 240 cases, four BMI types, six traction forces and two fractured sites were used. Results showed that joint load on major joints decreased as BMI increased. Additionally, joint load increased proportionally in the fractured tibia, but showed inverse tendency in the fractured femur. Control errors of up to 20% in repetitive control and approximately 30% in random control were measured, in comparison to estimated joint loads. Control error increased as traction force decreased. It is possible that applicability of robot systems to safe and precise surgical assistance can be validated. More precise traction control and real-time traction load monitoring technology will enable replacement of traction techniques in the near future.