• 제목/요약/키워드: vibration prevention

검색결과 161건 처리시간 0.023초

건축물(建築物) Elevator의 방진(防振)을 위한 진동특성(振動特性) 분석(分析) (The vibration quality analysis for the vibration prevention of the building elevator)

  • 전의식;조병후
    • 한국디지털건축인테리어학회논문집
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    • 제5권2호
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    • pp.29-35
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    • 2005
  • The interest about noise and vibration which occurs in buildings is increasing by a living level elevation recently. Particularly, the vibration which occurs from the elevator cage of the building is possibility of damage to the users of the building continuously. So, the purpose of this study is a place where it examines closely the vibrating unit of the elevator and propose the countermeasure of it.

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대형 여객선의 쾌적한 레져공간 확보 및 최적 방진설계 (Comfortable leisure space and prevention of vibration for large passenger ship)

  • 엄재광;권혁;박주현;한성용
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2008년도 춘계학술대회논문집
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    • pp.368-372
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    • 2008
  • Habitability is one of the most important points when a passenger ship is cruising. In particular, anti-vibration design should be considered preferentially to offer passenger a comfort cabin and leisure space. But, a passenger ship is different from a general commercial ship in the view point of the structural arrangement. It is restricted within narrow limits to reinforce wide panels and local structures of a passenger ship because of its interior design. Moreover, the allowable vibratory limits for a passenger ship are much lower than those of a commercial ship. In this study are introduced the procedure of the vibration analysis, the structural improvement method for prevention of vibration and the results of vibration measurement during exciter test and sea trials.

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대형 Ro-Ro Ferry의 진동 해석 및 방진 설계 (Vibration Analysis & Prevention of Vibration for a Large Ro-Ro Ferry)

  • 엄재광;한성용;권혁;이주헌
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2001년도 추계학술대회논문집 II
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    • pp.1050-1054
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    • 2001
  • Relatively high rotating speed propulsion shafting system of the large Ro-Ro Ferry has a greate risk of the resonance of the many wide local panels as well as the high frequency global vibratory modes. Therefore, from the initial design stage, it is necessary to control the vibration characteristics of the wide panels with detail so as not to be resonant with the blade number order excitation due to the propellers in the normal operating speed range. The procedure of the vibration analysis and the structural redesign for prevention of vibration is introduced.

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Vibration and Ergonomic Exposures Associated With Musculoskeletal Disorders of the Shoulder and Neck

  • Charles, Luenda E.;Ma, Claudia C.;Burchfiel, Cecil M.;Dong, Renguang G.
    • Safety and Health at Work
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    • 제9권2호
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    • pp.125-132
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    • 2018
  • Background: According to the US Bureau of Labor Statistics, musculoskeletal disorders (MSDs) accounted for 32% of all nonfatal injury and illness cases in 2014 among full-time workers. Our objective was to review and summarize the evidence linking occupational exposures to vibration and awkward posture with MSDs of the shoulder and neck. Methods: A literature search was conducted using the terms musculoskeletal disorders, vibration, and awkward posture. All types of observational epidemiologic studies, with the exception of case reports, published during 1998-2015 were included. Databases searched were MEDLINE (Ovid), Embase (Ovid), Scopus, Ergonomic Abstracts, NIOSHTIC-2, and Health and Safety Science Abstracts. Results: Occupational exposures to whole-body or hand-arm vibration were significantly associated with or resulted in MSDs of the shoulder and neck. Awkward postures while working were also associated with MSDs in these locations. These findings were consistent across study designs, populations, and countries. Conclusion: Occupational exposure to vibration and awkward posture are associated with shoulder and neck MSDs. Longitudinal studies are required to elucidate the mechanisms responsible for these associations, and intervention studies are warranted.

Analysis of dynamic behavior for truss cable structures

  • Zhang, Wen-Fu;Liu, Ying-Chun;Ji, Jing;Teng, Zhen-Chao
    • Steel and Composite Structures
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    • 제16권2호
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    • pp.117-133
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    • 2014
  • Natural vibration of truss cable structures is analyzed based upon the general structural analysis software ANSYS, energy variational method and Rayleigh method, the calculated results of three methods are compared, from which the characteristics of free-vibration are obtained. Moreover, vertical seismic response analysis of truss cable structures is carried out via time-history method. Introducing three natural earthquake waves calculated the results including time-history curve of vertical maximal displacement, time-history curve of maximal internal force. Variation curve of maximal displacement of node along span, and variation curve of maximal internal force of member along span are presented. The results show the formulas of frequencies for truss cable structures obtained by energy variational method are of high accuracy. Furthermore, the maximal displacement and the maximal internal force occur near the 1/5 span point. These provide convenient and simple design method for practical engineering.

서울지하철 3,4호선 Tunnel 굴착과 진동대책 조사연구(1)

  • 허진
    • 기술사
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    • 제15권2호
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    • pp.3-15
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    • 1982
  • The study on prevention measures for vibration and excavation of tunnel for the #3, #4, Seoul Subway. In the Seoul subway tunnel blasting, the drilling pattern and prevention method to seismic vibration are as follows as well as for adaptions of NATM, the supportings of roof and wall holes are arranged with control blasting. 1. The blasting is executed basically using the low velocity explosive such as slurry, Nitrate ammonium explosive, and F-I and F-II explosive for control blasting substituting of existing dynamite. 2. The cut holes are arranged with burn cut pattern and also must be arranged with M/S electrical delay caps substituting of ordinary do]ay caps. 3. Jack leg drills are used in Five Job sites and a jumbo drill in one job site. 4. In performance of safety work and in maintenance of building safety. The drilling length for blasting will not exceed 1.20 meter for round so that the vibration value shall carry below 0.3cm/sec. The harmonizing of better powder, better drilling machine and better technique is only the way of improving tunnelling efficiency and less vibration will help the dereasing of accidence.

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The Health Effect of Hand Arm Transmitted Vibration

  • Koo, Jung-Wan
    • 대한인간공학회지
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    • 제32권4호
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    • pp.303-308
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    • 2013
  • Objective: The aim of this study is to understand health effect of hand-arm transmitted vibration. Background: Electronic vibration tools have been used in many industries. These tools evoke hand-arm transmitted vibration that cause hand-arm vibration syndrome. Method: Various papers on the hand-arm transmitted vibration and its health effects have been reviewed to know what health effect caused. Results: Hand-arm transmitted vibration causes circulatory, neural, musculoskeletal and other disturbance. Conclusion: The previous studies focused on the epidemiology and physiology for hand-arm transmitted vibration. So, now we should focus on a prevention and guideline of hand-arm transmitted vibration. Application: These results can be used to know health effect of hand-arm transmitted vibration.

유리창 도청방지 장치의 성능평가 (Performance Estimation of a Window Shaker)

  • 김석현;김희동;허욱
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2007년도 춘계학술대회논문집
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    • pp.649-654
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    • 2007
  • Eavesdropping prevention performance is evaluated on a commercial window shaker, which is used to prevent a glass window from eavesdropping. Speech transmission index (STI) is introduced in order to estimate quantitatively the speech intelligibility of the sound detected on the glass window. Objective test by IEC standard using modulation transfer function (MTF) is performed to determine STI. Using Maximum Length Sequency (MLS) signal as a sound source, MTF is measured by accelerometers and laser doppler vibrometer. STI under different level of disturbing wave are compared to confirm the disturbing effect on the speech intelligibility.

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유한요소법과 ACSL을 이용한 Linear Stepping Motor의 진동특성에 관한 연구 (A Study on the Vibration Characteristics of Linear Stepping Motor using FEM and ACSL)

  • 이상호;김중기;오홍석
    • 한국산업융합학회 논문집
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    • 제6권2호
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    • pp.141-147
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    • 2003
  • In this paper, the vibration characteristics of a linear stepping motor(LSM) are analyzed using the finite element method(FEM : Flux2D) and ACSL. A magnetic equivalent circuit is based on the structure of the LSM, and then the electric equivalent circuit of the LSM is derived by solving equations for the magnetic equivalent circuit. A normal force is calculated using FEM. And the vibration characteristics of the LSM are simulated by the ACSL with the voltage equations, the thrust equations, the normal force equations and the kinetic equations, and are measured by LASER experimental system.

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