• 제목/요약/키워드: Bio-Mechanics

검색결과 49건 처리시간 0.032초

아데노이드 비대증에 의한 비정상 비강 내 유동의 PIV해석 (PIV Measurement on Airflows in the Abnormal Nasal Cavity with the Adenoid Vegetation)

  • 김성균;손영락
    • 대한기계학회논문집B
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    • 제27권4호
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    • pp.518-523
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    • 2003
  • Airflow in the nasal cavity of Korean adults is investigated experimentally by PIV measurement. Quantitative data for normal and abnormal nasal cavities with adenoid vegetation are obtained. The CBC PIV algorithm with window offset is used for PIV flow analysis. Average and RMS distributions are obtained for inspirational and expirational nasal airflows. Comparisons between western and Korean nasal airflows are appreciated. Due to the difference in geometry of the frontal part of nasal cavity, the flow near nares shows the difference. For the joint research on nasal deceases, PIV measurements of nasal airflow for nasal cavities with 50% and 70% adenoid vegetation are conducted for the first time. Comparisons in nasal airflows for both normal and abnormal cases are also appreciated.

비강 내 공기유동에 대한 실험 및 전산유동가시화 (Numerical and experimental flow visualization on nasal air flow)

  • 김성균;박준형;휜광림
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2008년도 춘계학술대회논문집
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    • pp.498-501
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    • 2008
  • Knowledge of airflow characteristics in nasal cavities is essential to understand the physiological and pathological aspects of nasal breathing. Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. In our laboratory, there have been a series of experimental investigations on the nasal airflow in normal, abnormal, and deformed nasal cavity models cavity models by PIV under both constant and periodic flow conditions. In this time normal and several deformed nasal cavity models, which simulate surgical operation, Turbinectomy, are investigated numerically by the FVM general purpose code and PIV analysis. The comparisons of these results are appreciated. Dense CT data and careful treatment of model surface under the ENT doctor's advice provide more sophisticated cavity models. The Davis (LaVision Co.) code is used for PIV flow analysis. Average and RMS distributions have been obtained for inspirational and expirational nasal airflows in the normal and deformed nasal cavities.

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코트 스포츠화의 착지충격 평가를 위한 유한요소 해석 (Finite Element Analysis for the Landing Impact Evaluation of Court Sport Shoes)

  • 김성호;조진래;류성헌;최주형
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 춘계학술대회
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    • pp.438-443
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    • 2004
  • Court sport shoes is consisted of several functional parts such as soles, upper and midfoot reinforcements. Currently, intensive research for court sport shoes considering functional parts is in progress world widely, but the shoes design relies only on the view point of kinesilogy and biomechanics until now. Thus, more scientific and reliable evaluation of shoes characteristics is definitely required. In this paper, we evaluate the landing impact of court sport shoes by using finite element method. We construct a shoes-leg coupled FEM model which can simulate effectively impact in running mode. From the numerical analysis results, the designer can establish the advanced design concepts and build up the detailed design standard for the specific court sport shoes under consideration.

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유한요소 해석을 통한 코트 스포츠화의 런닝시 충격력 평가 (Evaluation of Landing Impact Force of Court Sport Shoes at Running by Finite Element Analysis)

  • 김성호;조진래;류성헌;최주형
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.498-503
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    • 2004
  • A fundamental function of court sport shoes has been considered as the protection of human feet from unexpected injuries. But, recently its role for improving the playing competency is being regarded as a more important function. In connection with this situation, intensive efforts are being world-widely forced on the development of court sport shoes proving the excellent playing competency, by taking kinesiology and biomechanics into consideration. However, the success of this goal depends definitely on the shoes design based upon the reliable evaluation of shoes functional parts. This paper addresses the application of finite element method to the evaluation of landing impact force of court sport shoes. In order to reflect the coupling effect between leg and shoes accurately and effectively, we construct a fully coupled shoes-leg FEM model which does not rely on the independent experimental data any more. Through the numerical experiments, we assess the reliability of the coupled FEM model by comparing with the experimental results and investigate the landing impact characteristics of court sport shoes.

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비강 내 공기유동에 대한 실험 및 전산 유동가시화 (Numerical and Experimental Flow Visualization on Nasal Airflow)

  • 김성균;박준형;휜광림
    • 대한기계학회논문집B
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    • 제33권6호
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    • pp.461-467
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    • 2009
  • Knowledge of airflow characteristics in nasal cavities is essential to understand the physiological and pathological aspects of nasal breathing. Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. In our laboratory, there have been a series of experimental investigations on the nasal airflow in normal, abnormal, and deformed nasal cavity models by PIV under both constant and periodic flow conditions. In this time normal and several deformed nasal cavity models, which simulate surgical operation, Turbinectomy, are investigated numerically by the FVM general purpose code and PIV analysis. The comparisons of these results are appreciated. Dense CT data and careful treatment of model surface under the ENT doctor's advice provide more sophisticated cavity models. The Davis (LaVision Co.) code is used for PIV flow analysis. Average and RMS distributions have been obtained for inspirational and expirational nasal airflows in the normal and deformed nasal cavities.

3-1 타입 트리모프 캔틸레버의 마이크로발전 응용기술 개발 (Development of Application Technique for 3-1 Type Triple-morph Cantilever)

  • 김인성;주현규;정순종;김민수;송재성;전소현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.1303_1304
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    • 2009
  • With recent advanced in portable electric devices, wireless sensor, MEMS and bio-Mechanics device, the new typed power supply, not conventional battery but self-powered energy source is needed. Particularly, the system that harvests from their environments are interests for use in self powered devices. For very low powered devices, environmental energy may be enough to use power source. Therefore, in other to made piezoelectric energy harvesting device. The made 31type triple-morph cantilever was resulted from the conditions of $100k{\Omega}$, 0.25g, 154Hz respectively. The thick film was prepared at the condition of 6.57Vrms, and its power was $432.31{\mu}W$ and its thickness was $50{\mu}m$. And than, the fabricated piezoelectric cantilever was packaged for application.

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유한요소법을 이용한 하이브리드형 임플란트의 응력해석 (Stress Analysis of Hybrid Implant Using Finite Element Method)

  • 권영두;장석호;박상현;이상원
    • 대한기계학회논문집A
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    • 제32권3호
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    • pp.290-296
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    • 2008
  • After scientific verification of the osteointegration of dental implants, the overall efficiency of dental implants has been generally accepted. Thus, implants now play a major role in the clinical treatment of an edentulous mandible, and in the prosthetic maintenance equipment for partial edentulous mandible patients. Yet, for the successful long-term maintenance of implants, careful consideration of the bio-mechanics is needed to ensure that the maximum stress in the mandible as a result of chewing is maintained under a critical value. Accordingly, this study focuses on reducing the maximum stresses in an implanted mandible, especially in the cortical bone. Thus, the stresses in the implant and mandible are analyzed using finite element packages, including I-DEAS and NISA II/DISPLAY III, using a local zooming technique for a concentrated stress analysis. In addition, the von-Mises stress and principal stress in the mandible are both checked to determine the best combination.

31 타입 트리모프 켄틸레버의 마이크로 발전 특성 연구 (Micro-power Properties of 31Type Triple-morph Cantilever for Energy Harvesting Device)

  • 김인성;주현규;정순종;김민수;송재성;전소현
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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    • pp.220-221
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    • 2008
  • With recent advanced in portable electric devices, wireless sensor, MEMS and bio-Mechanics device, the new typed power supply, not conventional battery but self-powered energy source is needed. Particularly, the system that harvests from their environments are interests for use in self powered devices. For very low powered devices, environmental energy may be enough to use power source. Therefore, in other to made piezoelectric energy harvesting device. The made 31 type triple-morph cantilever was resulted from the conditions of 100k$\Omega$, 0.25g, 154Hz respectively. The thick film was prepared at the condition of $6.57V_{rms}$, and its power was $432.31{\mu}W$ and its thickness was $50{\mu}m$.

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호흡기 내 주기적 공기유동에 대한 PIV 계측 (The PIV Measurements on the Respiratory Gas Flow in the Human Airway)

  • 김성균
    • 대한기계학회논문집B
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    • 제30권11호
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    • pp.1051-1056
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    • 2006
  • The mean and RMS velocity field of the respiratory gas flow in the human airway was studied experimentally by particle image velocimetry (PIV). Some researchers investigated the airflow for the mouth breathing case both experimentally and numerically. But it is very rare to investigate the airflow of nose breathing in a whole airway due to its geometric complexity. We established the procedure to create a transparent rectangular box containing a model of the human airway for PIV measurement by combination of the RP and the curing of clear silicone. We extend this to make a whole airway including nasal cavities, larynx, trachea, and 2 generations of bronchi. The CBC algorithm with window offset (64 $\times$ 64 to 32 $\times$ 32) is used for vector searching in PIV analysis. The phase averaged mean and RMS velocity distributions in Sagittal and coronal planes are obtained for 7 phases in a respiratory period. Some physiologic conjectures are obtained. The main stream went through the backside of larynx and trachea in inspiration and the frontal side in expiration. There exist vortical motions in inspiration, but no prominent one in expiration.

비강 내 공기유동과 열 및 물질전달에 관한 연구 (Research on the nasal airflow and heat and mass transfer)

  • 김성균;휜광림;박준형
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.1479-1483
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    • 2008
  • The three main physiological functions of nose are air-conditioning, filtering and smelling. Knowledge of airflow characteristics in nasal cavities is essential to understand the physiological and pathological aspects of nasal breathing. Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. In our laboratory, there have been a series of experimental investigations on the nasal airflow in normal and deformed nasal cavity models by PIV under both constant and periodic flow conditions. In this time, airflow inside normal nasal cavity is investigated numerically by the FVM general purpose code. The comparisons with PIV measurement are appreciated. Heat and humidity transfer is dealt numerically. Dense CT data and careful treatment of model surface under the ENT doctor’s advice provide more sophisticated cavity models for both PIV experiment and numerical grid system. Average and RMS velocity distributions have been obtained for inspirational and expirational nasal. Temperature distribution, heat and humidity transfer through the mucosa are obtained.

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