• Title/Summary/Keyword: human vibration

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Prediction of Whole Body Vibration for CE Operatorsusing the Vertical Human Body Model (수직 인체 모델을 이용한 건설 중장비 운전자의 전신진동 예측)

  • Ham, Jeonghoon;Kim, Sunghwan;Kang, Hyunseok;Park, Sangkyu
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2013.04a
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    • pp.516-517
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    • 2013
  • Whole body vibration is very important for operators in construction equipment (CE) industry. There is ISO 2631 regulation to protect operators of CE. Recently WBV is one of critical performance parameters of CE to give operators much better comfortable working environment. And there are many kinds of numerically simplified human body model for the motor industry. We applied one human body model in ISO 5982 for the CE development at early stage. And we've checked the validity of this model to consider WBV by the operator comfort point of view.

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New Approaches to Assessing the Effects of Environmental Noise arid Vibration on Human (환경 소음ㆍ진동의 인체영향 평가에 대한 새로운 접근)

  • 정완섭;김용태
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.05a
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    • pp.768-771
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    • 2002
  • 국외 환경 소음과 진동은 이미 세계보건기구(WHO)와 UN산하 환경기관에서 선언한 바와 같이 “전세계인의 문제”(“global issues”)로 분류 인식하고 있으며, 이들 문제점들에 대한 접근은 선진국들의 국민 복지정책의 가장 핵심적 요소로 관리하고 있다. 예를 들어, WHO가 출판한 공중소음에 대한 지침서[1], 그리고 유럽공동체의 전문가 그룹이 작성한 보고서[2]들은 최근의 환경소음에 대한 새로운 접근의 필요성, 새로운 측정 및 평가 방법, 그리고 인체에 미치는 복합적 영향들의 새로운 평가 기법 개발, 그리고 환경 개선을 위한 장기적 계획과 실천 방안들을 구체적으로 제시하고 있다.(중략)

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An Analysis of the Vibration Characteristics through the Human Body (인체 내부에서의 진동 전달특성 분석)

  • 전종원;진용옥
    • The Journal of the Acoustical Society of Korea
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    • v.19 no.7
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    • pp.59-65
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    • 2000
  • This paper describes the analysis of vibration characteristics through the human body as the research for voice therapy and diagnosis. The oscillation signal is not external forces but the self-voice to be pronounced the vowels ('a', 'e', 'i', 'o', 'u'). The experiment system consists of microphones, accelerometers and amplifiers. The input data are stored by the computer. At the same time, the voice is stored by the microphone and the vibration signal of the human body is stored by accelerometer. The 63 points are appointed in head, neck, trunk of human body. The positions and number of times are changeable by the purpose. The analysis parameters are amplitude, phase, fundamental. frequency, formant and the correlation of vibration signal and voice is measured by coherence function. The results show that the vibration signals have characteristic vibration in the positions of human body.

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Evaluate of allowable acceleration for Occupants in Horizontal Vibration of Buildings according to Natural Frequency (고유주기에 따른 건축물의 수평진동에 대한 거주자의 허용가속도평가)

  • Cho, Kang-Pyo;Jeong, Seung-Hwan;Cho, Gi-Sung
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2008.04a
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    • pp.228-233
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    • 2008
  • In this paper, peak acceleration for horizontal vibration of buildings was estimated from the results of vibration tests using a shaking table. Human comfort of occupants is supposed to be satisfied according to the peak acceleration in NBCC and ISO6897, which have been used by Korean structural engineers. In the paper, we used a one-dimensional shaking table for horizontal vibration tests, which was mounted with a vibration house similar to a living space. Experimental results were obtained according to increasing accelerations in the range of 0.2Hz through 1.2Hz of frequency with five experimental groups, each of which was composed of eight persons. We obtained performance curves by dividing the distribution of perception from horizontal vibration tests into the ranges of 0${\sim}$25%, 26${\sim}$50%, 51${\sim}$75%, 76${\sim}$100% and then fitting the curves. Also we made a questionnaire based on human comfort criteria of foreign countries, and examined the feelings of subjects. From the results of horizontal vibration tests, it was found that acceleration of perception was low when frequency was high, and that visual and auditory senses affect the human perception for horizontal vibration of buildings.

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A Study on the Evaluation of Vibration's Environment in a Korean Rail Vehicles based on the Human Vibration (인체 진동을 고려한 국내의 철도 차량의 진동 환경 평가에 관한 연구)

  • 김진기;정완섭;홍동표
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.05a
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    • pp.1100-1104
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    • 2001
  • This paper introduces experimental results related to the vibration ride conditions that a korean male subject experienced in the railway trains and the express bus. Two types of railway train's, Samaulho and Mugunghwaho, and the express bus were chosen to measure how much the whole-body vibrations of the back, hip and feet are exposes to the subject. Measured vibration signals were analysed to assess the ride conditions quantitatively and qualitatively. Analysed results are illustrated to see how much typical public transportation systems in korea expose vibration to passengers.

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Vibration behavior of large span composite steel bar truss-reinforced concrete floor due to human activity

  • Cao, Liang;Li, Jiang;Zheng, Xing;Chen, Y. Frank
    • Steel and Composite Structures
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    • v.37 no.4
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    • pp.391-404
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    • 2020
  • Human-induced vibration could present a serious serviceability problem for large-span and/or lightweight floors using the high-strength material. This paper presents the results of heel-drop, jumping, and walking tests on a large-span composite steel rebar truss-reinforced concrete (CSBTRC) floor. The effects of human activities on the floor vibration behavior were investigated considering the parameters of peak acceleration, root-mean-square acceleration, maximum transient vibration value (MTVV), fundamental frequency, and damping ratio. The measured field test data were validated with the finite element and theoretical analysis results. A comprehensive comparison between the test results and current design codes was carried out. Based on the classical plate theory, a rational and simplified formula for determining the fundamental frequency for the CSBTRC floor is derived. Secondly, appropriate coefficients (βrp) correlating the MTVV with peak acceleration are suggested for heel-drop, jumping, and walking excitations. Lastly, the linear oscillator model (LOM) is adopted to establish the governing equations for the human-structure interaction (HSI). The dynamic characteristics of the LOM (sprung mass, equivalent stiffness, and equivalent damping ratio) are determined by comparing the theoretical and experimental acceleration responses. The HSI effect will increase the acceleration response.

Design and Control of a Dynamic PLS of the Biped Walking RGO for a Trainning of Rehabilitation considering Human Vibration (인체진동을 고려한 재활훈련용 이족보행 RGO 보조기의 생체역학적 해석 <인체진동 응력해석과 FEM을 중심으로>)

  • 장대진;김명회;양현석;백윤수;박영필;박창일
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.05a
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    • pp.752-759
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    • 2002
  • This paper presented a design and a control of a biped walking RGO and walking simulation by this system. The biped walking RGO was distinguished from the other one by which had a very light-weight and a new RGO type with 12-servo motors. The vibration evaluation of the dynamic PLS on the biped walking RGO was used to access by the 3-axis accelerometer with a low frequency vibration for the spinal cord injuries. The gait of a biped walking RGO depended on the constrains of mechanical kinematics and the initial posture. The stability of dynamic walking was investigated by a ZMP (Zero Moment Point) of the biped walking RGO. It was designed according to a human wear type and was able to accomodate itself to a human environments. The joints of each leg were adopted with a good kinematic characteristics. To test of the analysis of joint kinematic properties, we did the strain stress analysis of the dynamic PLS and the analysis study of FEM with a dynamic PLS. It will be expect that the spinal cord injury patients are able to recover effectively with a biped walking RGO.

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Assesment on the Transformation of Psychological Risk Images due to Development of Flight Skills (조종 숙련도 변화에 따른 심리적 리스크 이미지의 변화에 대한 평가)

  • Kim, Yeong-Gwan;Im, Hyeon-Gyo
    • Journal of the Ergonomics Society of Korea
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    • v.22 no.1
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    • pp.57-67
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    • 2003
  • The resonance behaviour needs be understood to identify the mechanisms responsible for the dynamic characteristics of human body, to allow for the non-linearity when predicting the influence of seating dynamics. and to predict the adverse effects caused by various magnitudes of vibration. However, there are currently no known studies on the effect of vibration magnitude on the transmissibility to thoracic or lumbar spine of the seated person. despite low back pain(LBP) being the most common ailment associated with whole-body vibration. The objective of this paper is to develop a proper mathematical human model for LBP and musculoskeletal injury of the crew in a maritime vehicle. In this study, 7 degree-of-freedom including 2 non-rigid mass representing wobbling visceral and intestine mass, is proposed. Also. when compared with previously published experimental results, the model response was found to be well-matching. When exposed to various of vertical vibration, the human model shows appreciable non-linearity in its biodynamic responses. The relationships of resonance for LBP and musculoskeletal injury during whole-body vibration are also explained.

Tuned mass dampers for human-induced vibration control of the Expo Culture Centre at the World Expo 2010 in Shanghai, China

  • Lu, Xilin;Ding, Kun;Shi, Weixing;Weng, Dagen
    • Structural Engineering and Mechanics
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    • v.43 no.5
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    • pp.607-621
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    • 2012
  • The Expo Culture Centre is one of the permanent buildings at the World Expo 2010 in Shanghai, China. The main structure has an oval shape and consists of 36 radial cantilever steel trusses with different lengths and inner frames made of concrete-filled rectangular steel tube members. Tuned mass dampers are used to reduce the excessive vibrations of the sixth floor that are caused by human-induced resonance. A three-dimensional analytical model of the system is developed, and its main characteristics are established. A series of field tests are performed on the structure, and the test results show that the vertical vibration frequencies of most structural cantilevers are between 2.5 Hz and 3.5 Hz, which falls in the range of human-induced vibration. Twelve pairs of tuned mass dampers weighing 115 tons total were installed in the structure to suppress the vibration response of the system. These mass dampers were tuned to the vertical vibration frequency of the structure, which had the highest possibility of excitation. Test data obtained after the installation of the tuned mass dampers are used to evaluate their effectiveness for the reduction of the vibration acceleration. An analytical model of the structure is calibrated according to the measured dynamic characteristics. An analysis of the modified model is performed and the results show that when people walk normally, the structural vibration was low and the tuned mass dampers have no effect, but when people run at the structural vibration frequency, the tuned mass dampers can reduce the floor vibration acceleration by approximately 15%.

Proposal of an Equation for the Evaluation of Discomfort of a Seated Human Body Due to the Differential Vertical Vibration at the Seat and the Floor (시트와 바닥 진동의 위상차가 안락성에 미치는 영향을 평가하기 위한 수식의 제안)

  • 장한기
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.12 no.8
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    • pp.626-631
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    • 2002
  • A modified equation for the evaluation of discomfort of a seated human body exposed to differential vibration at the seat and the floor was proposed in this paper. Through the review and analysis of the preceding studies, effect of phase difference between the seat and the floor vibration on discomfort were quantitatively identified. The phase effect was shown to be governed by not only phase difference between the two vibrations but both their frequency and the magnitude, which means the present equation for the evaluation of perceptual amount of vibration provided by ISO 2631-1 should be modified. The proposed equation was developed such that the correction function was multiplied to the present equation. The correction function consisted of three parts, each of them represented the effect by phase difference, frequency and vibration magnitude on discomfort respectively.