• 제목/요약/키워드: Static experiment

검색결과 761건 처리시간 0.032초

전자처리 스페클 패턴 간섭법(ESPI)을 이용한 복합재료의 진동 특성 해석에 관한 연구 (A Study on the Vibration Characteristics Analysis of Composite Materials by Using Electronic Speckle Pattern Interferometry Method)

  • 김경석;정성균;정현철;양승필;김형택;김동일;이승환
    • 한국정밀공학회지
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    • 제15권9호
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    • pp.68-74
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    • 1998
  • The ESPI(Electronic Speckle Pattern Interferometry) is a real time, full-field, non-destructive optical measurement technique that allows static and dynamic deformation analysis and surface shape measurements of engineering structures. e .g. turbine blades. vehicle engine components, body panels, etc. This technique is very similar to holographic interferometry, but uses a solid static camera and an image processing board for recording and digital processing of speckle patterns. In this paper it is presented that FEM results for the free vibration of symmetrically laminated composite as [30/-30/90]s. The natural frequencies of laminated composite rectangular plates having the particular boundary condition are experimentally obtained. In order to demonstrate the validity of the experiment, FEM analysis using ANSYS was performed and natural frequencies experimentally obtained is compared with calculation by FEM analysis. The results obtained from both experiment and FEM analysis show a good agreement.

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차량용 시트의 설계품질 향상을 위한 안전공학 및 인간공학에 관한 연구 (A study on the safety and human engineering for the design quality improvement of vehicle seats)

  • 이장무;염영하;신승훈
    • 오토저널
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    • 제8권3호
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    • pp.55-67
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    • 1986
  • The safety and comfort of car seats wee studied by utilization of engineering analysis/ experiment and human engineering data. As important factors of the static seating comfort, static spring constant, body pressure distribution, driving posture were discussed. In connection with the dynamic seating comfort, vibrational characteristics of domestic car seats(natural frequencies, damping, frequency spectrum, transmission ratio)were measured and discussed. Finally, the safety of the seat was analyzed and evaluated through calculation and experiments.

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철근콘크리트뼈대 구조물의 정적 비선형 해석에 관한 연구 (A Study on the Nonlinear Analysis of R/C Frames Structures subjected to Static Loads)

  • 심종성;조민수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1992년도 가을 학술발표회 논문집
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    • pp.196-201
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    • 1992
  • The purpose of this study is to develop the computer software for the nonlinear analysis of R/C frame structure under static loads. For this purpose, strain-rate dependant material model and physical element model considering both flexural and shear deformation are adopted and they are connected with 'TWO-D'which is commerical software for elastic structural analysis. The analytical results using the developed software are compared to the experiment results and they are generally satisfactory.

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3차원 유한요소 모델링을 통한 공작기계 구조의 정적 변형도 해석 (Three dimensional finite element analysis of static deflections of a machine tool structures)

  • 김현석;이수정;정광섭;이대길
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1993년도 추계학술대회 논문집
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    • pp.638-643
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    • 1993
  • The three dimensional finite element models for the basic deflection of linear motion guides and ball screws were developed. Form the comparison of the results calculated by the finite element method with those by the experiment, it was proved that the modeling method might be applied to real machine tool structures. Form the structural analysis of the headstock of the machine tool, it was found that the static stiffness was calculated within 6.5% error

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CHARACTERITICS OF MODIFIED PD OF ELECTROMAGNETIC SUSPENSION SYSTEM FOR NON-CONTACT STEEL PLATE CONVEYANCE

  • Xu, Dehong;Sun, Xiao;Feng, Wei
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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    • pp.131-136
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    • 1998
  • Based on the linear model of electromagnetic suspension (EMS) system, it is able to be further simplified into a standard second-order model with a modified PD control. In this paper static and dynamic characteristics of EMS with modified PD control are investigated when suspended weight of steel plate change. A experimental system has been built to verify static and dynamic characteristics of EMS system. Simulation and experiment are both given.

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Experimental and theoretical studies on SHS column connection with external stiffening ring under static tension load

  • Rong, Bin;You, Guangchao;Zhang, Ruoyu;Ma, Xu;Quan, Xinxin
    • Steel and Composite Structures
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    • 제28권2호
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    • pp.167-177
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    • 2018
  • In order to investigate mechanical properties in the core area of Square Hollow Section(SHS) column connection with external stiffening ring, four specimens were tested under the static tension load. The failure modes, load-displacement curves and strain distribution were analyzed to study the mechanical properties and the load transfer mechanism of the core area of connections. The connections behave good ductility and load-bearing capacity under the static tension load. Parametric analysis was also conducted, in which the thickness of steel tube, extended width and thickness of the stiffening ring were considered as the parameters to investigate the effects on mechanical properties of the connections. Based on the experimental results, an analytical method for the bearing capacity of connection with external stiffening ring under the static tension load was proposed. The theoretical results and the experimental results are in good agreement, which indicates that the theoretical calculation method of the bearing capacity is advisable.

승마기구 운동이 만성 뇌졸중 환자의 정적 균형능력에 미치는 영향 (Effects of Mechanical Horseback Riding Exercise on Static Balance of Patient with Chronic Stroke)

  • 조운수;조성현
    • 한국산학기술학회논문지
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    • 제16권3호
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    • pp.1981-1988
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    • 2015
  • 본 연구의 목적은 승마기구 운동이 만성 뇌졸중 환자의 정적균형 능력에 어떠한 영향을 미치는지 알아보는 것이다. 연구대상자는 뇌졸중 진단을 받은 환자 30명으로서 승마기구 운동군과 대조군으로 무작위 분류하였다. 대조군은 운동치료를 하루에 1회씩 받았으며, 실험군은 하루 1회의 운동치료 외에 별도의 시간에 승마기구 운동을 받았다. 승마기구 운동은 6주 동안 주 3회, 회당 20분씩 실시하였다. 집단 간 비교를 위해 independent t-test를 실시하였고, 집단 내 기간별 비교를 위해 paired t-test를 실시하여 분석하였다. 본 연구의 결과, 운동 후 승마기구 운동군의 눈 감고 선 자세에서는 균형에 유의한 차이가 있었으나, 승마기구 운동군과 대조군의 그룹간 비교에서는 유의한 차이가 나타나지 않았다. 앞으로 승마기구 운동이 뇌졸중 환자의 기능에 어떠한 영향을 미치는지 알아보는 다양한 임상적 연구가 필요할 것으로 생각된다.

해상 양식시설의 계류시스템 실험 및 해석 (Experiment and Analysis of Mooring System for Floating Fish Cage)

  • 김진하;김현주;홍섭
    • 한국수산과학회지
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    • 제34권6호
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    • pp.661-665
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    • 2001
  • 해상가두리의 안정성 및 기능성 향상을 위한 최적 계류시스템을 개발하기 위하여 천해역에 적합한 계류시스템을 검토하여 유연부 이 계류시스템을 선정하였다. 이를 위한 해석프로그램을 정립하고, 수리모형실험 결과와 비교하였다. 해석프로그램의 타당성을 확인 한 후, 적용할 만한 계류시스템을 구성하고 수치계산을 통하여 해상가두리를 위한 적정 계류시스템을 제시하였다. 해상가두리의 계류시스템은 유연부이 계류시스템이 권장되며, 계류배치는 탁월 외력환경과 일치하는 방향으로 하고, 수평계류삭인 나일론 로프는 해상가두리 길이의 0.5배 이상, 경사 와이어 로프는 수심의 2배 이상이 바람직한 것으로 나타났다. 또한, 중간부 이의 증설은 계류장력 및 표류변위를 감소시키는 효과를 가질 것으로 판단된다. 차후, 해상가두리의 동적응답 특성을 계류시스템 해석모델의 개발과 계류시스템의 설계가 요구된다.

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자기변형잉크젯헤드에서 토출된 액적의 정적 착지정확도 모델링 및 실험적 검증 (Modeling and Experimental Verification on Static Landing Accuracy of Droplets from Magnetostrictive Inkjet Head)

  • 유은주;박영우
    • 한국정밀공학회지
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    • 제30권1호
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    • pp.77-84
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    • 2013
  • Most research on the inkjet printing technology has focused on the development of inkjet head itself, and of process, not on the landing accuracy of the droplets to a target. Thus, this paper presents the modeling and experimental verification on the static landing accuracy and precision of the droplets from the magnetostrictive inkjet head. A simple model based on the angle deviation of a nozzle tip and on a distance to a substrate is considered, assuming that there is no ambient effect. The angle deviation of the nozzle tip is determined by using its digital image with the aid of a pixel calculation program, and the distance to the substrate is set to 1 mm. Three experiments have planned and preformed. The first experiment is to collect the initial data for the landing distribution of the droplets. The second experiment is to collect the repeatability data of the stage used. Then, these data are used to rederive the equation for the final landing position of the droplet. The final experiment is to verify the equation and to show the calibration results. The respective landing accuracy of the droplet after calibration on the x-axis and on y axis has improved from $338.51{\mu}m$ and $-133.63{\mu}m$ to $7.06{\mu}m$ and $13.11{\mu}m$. The respective percent improvement on the x-axis and on y axis reaches about 98 and about 90. The respective landing precision of the droplet after calibration on the x-axis and on y axis has improved from ${\pm}182.6{\mu}m$ and ${\pm}182.88{\mu}m$ to ${\pm}24.64{\mu}m$ and ${\pm}42.76{\mu}m$. The respective percent improvement on the x-axis and on y axis reaches about 87 and about 77.

초음파 치료와 정적 스트레칭이 뒤넙다리근의 유연성과 정적균형에 미치는 영향 (The Effect of Therapeutic Ultrasound and Static Stretching of the Hamstring Muscle on Flexibility and Static Balance Ability)

  • 조승봉;박미영;원지선;김예린;홍준택;김성호
    • 대한물리치료과학회지
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    • 제26권1호
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    • pp.45-53
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    • 2019
  • Background: The purpose of present study was to examine the effect of ultrasound therapy and static stretching on hamstring length and balance. Design: Randomized Controlled Trial. Methods: A total of 30 adults in S college, Seongnam city, Gyeonggi-do, between the ages of 20-30 were randomly assigned to two groups. Group 1 (n=15) had ultrasound therapy, called US group. Group 2 (n=15) had static stretching, called SS group. Measurements were taken prior to starting the program and after completing the experiment using Finger to floor test and Active knee extension test to get the results of hamstring flexibility and the ability of static balance. Paired t-test was used to compare each group pre-test values to post-test values and to compare US post-test values to SS post-test values on PASW 18.0. Results: 1) Both hamstring SS group and US group had significant increase (p<.05) in Finger to floor test and Active knee extension test. 2) Dominant leg standing had significant change (p<.05) only in US group. 3) There was no significant difference between US group and SS group. Conclusion: Results showed that US group and SS group had an effect on changes in hamstring length (p<.05). However, they did not show a significant increase in static balance. Further effective studies on hamstring SS group and US group were needed based on this examination.