• 제목/요약/키워드: Vibration test

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소형 위성 발사체의 정현파 진동 시험을 위한 가진 입력 결정 (Determination excitation spectrum for the sinusoidal vibration test of the small satellite launch vehicle)

  • 박순홍;윤세현;서상현;정호경;장영순
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 춘계학술대회논문집
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    • pp.193-196
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    • 2006
  • Vibration overtests have been common problems in aerospace industry. A test item can be overtested at its resonances when it is excited by the traditional spectrum enveloping peaks in the field acceleration spectrum. This paper introduces the method of modifying the excitation specification to alleviate the overtesting problem. A vibration analysis was performed to estimate interface forces and acceleration responses. A finite element model that was verified by an extensive modal test enabled us to shape the acceleration input accurately The produced notched input will be used in the sinusoidal vibration test of the small satellite launch vehicle.

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저궤도 지구관측위성의 광학탑재체 지지구조물 동환경시험 결과분석 (Dynamic Test Results Assessment on the Optical Bench of LEO Satellite)

  • 김경원;김진희;이주훈;김선원;진익민;박종성
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 춘계학술대회논문집
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    • pp.242-245
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    • 2006
  • This paper is an assessment on the dynamic test results of optical bench for LEO satellite. According to the design requirements, optical bench was designed and manufactured. Dynamic test was performed to verify stability of optical bench. Low level random vibration test, sine burst test and sine vibration test are carried out to identify dynamic characteristics and to verify static strength and safety under quasi-static load conditions. From the result it can be stated that the optical bench is well qualified under the launch environmental conditions.

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도로 노면 조건을 고려한 차량 엔진 주변 부품의 피로손상도 분석 (Analysis of Fatigue Damage of the parts around the vehicle engine with Respect to Road surface conditions)

  • 신성영;김찬중;이봉현
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 추계학술대회 논문집
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    • pp.581-586
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    • 2014
  • In general vibration test considers both harmonic vibration and random vibration, When developing the vehicle component. But the effect of harmonic vibration is larger in the parts around the vehicle engine, sole testing the harmonic vibration is considered. In this study, the fatigue damage of the linear system fixed around the engine is analyzed when the effect of random vibration is higher, harsher than the normal road surface condition. In condition the vehicle speed and the engine RPM are similar, the higher the harshness of the road surface condition is, the larger the fatigue damage level is. Therefore both random vibration and harmonic vibration must be considered in vibration test of components around the engine. Proposing the sine on random(SOR) vibration test that can exam considering both of vibrations, harmonic and random.

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상시진동실험을 이용한 남해대교의 동특성 평가 (Estimation of Dynamic Characteristics of Namhae Suspension Bridge Using Ambient Vibration Test)

  • Kim, Nam-Sik;Kim, Chul-Young;Jung, Dae-Sung;Yoon, Jah-Geol
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2002년도 추계학술대회논문초록집
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    • pp.396.1-396
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    • 2002
  • The AVT under traffic-induced vibrations was carried out on Namhae Suspension bridge in Korea. Mode shapes as well as natural frequencies up to the 15th mode were acquired exactly, and the effect of traffic mass and temperature on measured natural frequencies was investigated. The results from the AVT are compared with those from forced vibration test(FVT) and FE analysis. (omitted)

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냉연코일강판 수송용 화차의 안전성 평가를 위한 차체하중시험과 진동시험 (A safety evaluation on the loading and vibration test for transport freight car of cold rolled coil sheet)

  • 김원경;정종덕;윤성철;홍용기
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.1499-1502
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    • 2003
  • This paper describes the result of carbody and vibration test for freight car. The purpose of the test is to evaluate an safety which carbody structure shall be considered fully sufficient rigidity so as to load a freight car under maximum load and operating condition on line track. The test carbody is constructed by RS korea co., LTD. in accordance with KNR specfication. The test cases of the carbody is tested the vertical load and compressive load to verify the strength and stillness. The vibration test is tested for analysis and evaluation of vibration, to allow for the fact that mechanical vibration in railway vehicles have specific characteristics.

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가진기의 동적 거동 해석 (Analysis on the Dynamic Behavior of Shaker)

  • 한상보;김윤환;송장규
    • 소음진동
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    • 제8권1호
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    • pp.75-80
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    • 1998
  • It is a well known fact that the shaker used in the vibration test interacts with the test structure and thus influences the test results. A two degree of freedom model of shaker is suggested and the vibration parameters of this model is experimentally extracted. According to this experimental results, the vibration parameters of the shaker can vary with respect to the test structure as well as the stinger used in the connecting mechanism. It is also found that the vibration parameters of the shaker provided by the manufacturer can not be accurate and these parameter values should be revaluated based on the test environments.

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Spacecraft vibration testing: Benefits and potential issues

  • Kolaini, Ali R.;Tsuha, Walter;Fernandez, Juan P.
    • Advances in aircraft and spacecraft science
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    • 제5권2호
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    • pp.165-175
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    • 2018
  • Jet Propulsion Laboratory has traditionally performed system level vibration testing of flight spacecraft. There have been many discussions in the aerospace community for more than a decade about spacecraft vibration testing benefits or lack thereof. The benefits and potential issues of fully assembled flight spacecraft vibration testing are discussed herein. The following specific topics are discussed: spacecraft screening test to uncover workmanship problems for launch dynamics environments, force- and moment-limited vibration testing, potential issues with structural frequency identification using base shake test data, and failures related to vibration shaker testing and ways to prevent them.

기계류부품의 가진시험 조건에 관한 연구 (Study of Vibration Test Condition for Machinery Component)

  • 김형의;박종원;정동수;강보식
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제6권1호
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    • pp.27-36
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    • 2006
  • It is increasingly important to ensure that a given vibration test specification of a particular machinery component is appropriately established by considering its real environmental conditions. Vibration test standards for electrical components are well documented, for example in an IEC 60068 series, while standards for machinery components are rarely found except a few military standards. Thus many vibration tests are performed based on the military standards. However, a test based on these military standards often results in over-testing, and under-testing in some cases due to the different environmental conditions. Also, these standards require an appropriate tailoring that may not be easily accomplished. In this paper, various international and military standards are compared and investigated to obtain test specifications relevant for machinery components. Also appropriate tailoring methods are demonstrated through a case study.

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콘크리트의 유동성에 미치는 타설진동의 영향 (Effects of Internal Vibration on Flowability of Fresh Concrete)

  • 최수경
    • 콘크리트학회논문집
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    • 제12권3호
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    • pp.77-85
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    • 2000
  • Various concretes are used for construction works depending on the types of structure, building element and method of construction. An internal vibration work is one of the important processes for adequately pouring various concrete into a certain form. This study was undertaken to find out the effects of internal vibration on flowability of fresh concrete by concrete flow test under eight conditions of vibration. Presumable equation models also were created to show all vibration effects without regard to kinds of concrete. As the results of this study, the degree of vibration effects were varied according to the properties of concrete. Acceleration amplitude of vibration that applied to fresh concrete was effective value of the properties of vibration in a viewpoint of flowability. Moreover, This research presents the presumed equation models including variables created by acceleration amplitude and measuring value of vibrated concrete flow test. These models are presumable methods of vibration effects regardless of kinds of concrete.

흥인지문의 진동특성 및 상반성 분석 (Investigation on Vibration Characteristics and Structural Reciprocity of Heunginjimun)

  • 최재성;이성경;민경원;윤원규;김덕문
    • 한국소음진동공학회논문집
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    • 제20권4호
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    • pp.338-347
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    • 2010
  • Heunginjimun designated as a Treasure No.1 is a two-story wooden structure with 5 bay and 2 bay in its front and side views, respectively. This paper presents an investigation on vibration characteristics of Heunginjimun through both ambient vibration and impact hammer tests. Ambient vibration test was performed to identify the natural frequency of Heunginjimun from the spectrum analysis of time history. Impact hammer test was undertaken to find the frequency of Heunginjimun which is affected by the surrounding traffics and to verify the reciprocal principle for the wooden structural system. Ambient vibration test results of Heunginjimun showed that the natural frequencies in two principal axes 1.5 Hz and 1.1 Hz, respectively. It was confirmed from impact hammer tests for a ground that the frequency of 4.2 Hz is caused by the traffics surrounding Heunginjimun. It was also observed that from the impact hammer test results between two locations in Heunginjimun that the transfer functions measured from two corresponding locations coincided well with each other. This result shows that the wooden structural system is globally linear, and the reciprocal principle is established.