http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
골수술용 압전형 초음파 의료기기 개발을 위한 유한요소해석 및 이의 실험적 검증
송태하,이중호,최종균,이희원,Song, Tae-Ha,Lee, Jung-Ho,Choi, Jong Kyun,Lee, Hee Won 대한의용생체공학회 2022 의공학회지 Vol.43 No.5
In this study, the optimal driving frequency was derived through finite element analysis (FEA) to optimize the developed piezoelectric ultrasonic medical devices(PUMD) for bone surgery. The core of the PUMD is the piezoelectric ceramic (PZT), which is a vibrator that generates vibration energy. The piezoelectric ceramic shows the maximum current value with respect to the input voltage at the resonance frequency, which generates the maximum mechanical vibration. In the past, various studies have been conducted related to the analysis of PUMD, but most of the research so far has been limited to free vibration analysis. However, in order to derive the accurate resonant frequency, the initial stress generated by bolt tightening in the bolt-clamped Langevin type transducer (BLT) must be considered. In this study, after designing a PUMD, the driving performance according to the bolt tightening value was analyzed through FEA, and this was experimentally verified. First, the resonance mode and frequency response were confirmed through modal and harmonic analysis at 20-40 kHz, which is known as the optimal driving frequency band of PUMD for bone surgery. In addition, the design of the PUMD was confirmed by checking the mechanical behavior of the tip and the piezoelectric ceramic at the resonant frequency. Consequentially, the characteristic evaluation was performed, and it was confirmed that the resonant frequency result derived through the FEA was reasonable. Through this study, we presented a more rational FEA method than before for BLT transducers. We expect that this will shorten the time and cost of developing a PUMD, and will enable the development of more stable and high-quality products.
이식거부반응을 줄이기 위한 cyclosporine A 탑재형 약물전달체의 개발
송태하(Tae-Ha Song),장진아(Jinah Jang),심진형(Jin-Hyung Shim),조동우(Dong-Woo Cho) 대한기계학회 2013 대한기계학회 춘추학술대회 Vol.2013 No.12
Systemic administration of Cyclosporine A (CsA) is frequently associated with a number of side effects which restrict the use of effective dose of immunosuppressant drug. For the purpose of local and controlled delivery of CsA, scaffoldbased CsA delivery system was developed. CsA-Poly(lactic-co-glycolic) acid(PLGA) microspheres-loaded drug carriers were prepared using Multi-head Tissue/Organ Building System which is based on the 3D printing technique. Proinflammatory cytokine expressions, which are secreted by Concanavalin A activated spleen cells such as Interleukin-2, Interleukin-17 and Interferon-gamma were significantly decreased by acting of CsA-loaded drug carrier in-vitro. Human lung fibroblasts-seeded CsA-loaded drug carriers were subcutaneously implanted into the BALB/c mouse model. Infiltration of mononuclear cells and CD4+, CD8+ T-cell populations at the site of implantation were investigated by H&E staining and immunohistochemistry. Mononuclear cells infiltration and population of T-cells were significantly suppressed by CsA-loaded drug carrier in-vivo. These results show that the CsA-loaded drug carrier can be a promising solution for local and controlled delivery of CsA.
골수술용 초음파 핸드피스 유한요소해석 및 이의 실험적 검증
송태하(T. H. Song),박철민(C. M. Park),이중호(J. H. Lee),이희원(H. W. Lee),최종균(J. K. Choi) Korean Society for Precision Engineering 2021 한국정밀공학회 학술발표대회 논문집 Vol.2021 No.11월
현대 의학에서 초음파는 각종 질병의 진단에서부터 치료기기, 치과용 핸드피스 및 외과용 수술기기까지 다양한 의료 분야에 응용되어 사용되고 있다. 본 연구에서는 골수술용 초음파 핸드피스의 최적화를 위해 유한요소해석(Finite Element Method, FEM)을 통해 개발중인 초음파 핸드피스의 최적 구동을 위한 설계를 확정 하였다. 또한 최종적으로 개발한 초음파 핸드피스 시작품의 성능평가를 통해 골수술용 수술기기로서의 유효성을 확인 하였다. 개발한 골수술용 핸드피스 해석을 위해 본 연구에서는 ANSYS 19.0 ACT Piezo and MEMS Extension 을 활용하여 압전소자(PZT) 기반의 핸드피스 해석을 수행하였다. 최적의 고유진동수 도출을 위해 볼트 조임 란쥬방형 진동자(Bolt-clamped Langevin Type Transducer, BLT)에서 발생하는 초기응력(응력전위)을 고려 하였으며, 볼트 조임값의 변화에 따른 핸드피스의 구동성능을 평가하여 최적의 볼트조임 값을 도출 하였다. 또한 골수술용 초음파 핸드피스의 최적 구동 주파수 대역대로 알려진 20-40 kHz 에서 모달해석(Modal Analysis) 및 주파수 응답(Harmonic Response)을 확인 하였으며 효과적인 골절삭을 위한 Mode(직진선형운동)에서 핸드피스 팁 끝단의 변위를 확인함으로서 최적의 핸드피스의 설계안을 도출 하였다. 최종적으로 제작된 핸드피스는 임피던스 측정 및 변위측정 등의 성능평가를 수행하였으며 해석을 통해 제시된 주파수 대역내 내에서의 유효성 및 안정성을 확인하였다.
Parylene-C 코팅된 의료용 SUS304 소재의 결합력 향상을 위한 플라즈마 처리 효과
김동국,송태하,정용훈,강관수,윤덕규,김민욱,우영재,서요한,김경아,노지형 한국표면공학회 2022 한국표면공학회지 Vol.55 No.6
Parylene-C which was mainly used for industries such as electronics, machinery and semiconductors has recently been in the spotlight in the medical field due to its properties such as corrosion resistance and biocompatibility. In this study we intend to derive a plan to improve the bonding strength of Parylene-C coating with the SUS304 base material for medical use which can be applied to various medical fields such as needles, micro needles and in vitro diagnostic device sensors. Through plasma pretreatment the bonding strength between Parylene-C and metal materials was improved. It was confirmed that the coated surface was hydrophobic by measuring the contact angle and the improvement of the surface roughness of the sample manufactured through CNC machining was confirmed by measuring the surface roughness with SEM. Through the above results, it is thought that it will be effective in increasing usability and reducing pain in patients by minimizing friction when inserting medical devices and in contact with skin. In addition it can be applied to various application fields such as human implantable stents and catheters, and is expected to improve the performance and lifespan of medical parts.