• Title/Summary/Keyword: shaking time

Search Result 334, Processing Time 0.029 seconds

Wind Response Control Performance of a Two-way Tuned Liquid Mass Damper Using Real-Time Hybrid Shaking Table Testing Method (실시간 하이브리드 진동대 실험법에 의한 양방향 TLMD의 풍응답 제어성능평가)

  • Heo, Jae-Sung;Lee, Sung-Kyung;Lee, Sang-Hyun;Park, Eun-Churn;Kim, Hong-Jin;Jo, Bong-Ho;Jo, Ji-Seong;Kim, Dong-Young;Min, Kyung-Won
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2007.11a
    • /
    • pp.189-194
    • /
    • 2007
  • An experimental real-time hybrid method, which implements the wind response control of a building structure with only a two-way TLMD, is proposed and verified through a shaking table test. The building structure is divided into the upper experimental TLMD and the lower numerical structural part. The shaking table vibrates the TLMD with the response calculated from the numerical substructure, which is subjected to the excitations of the measured interface control force at its top story and an wind-load input at its base. The results show that the conventional method can be replaced by the proposed methodology with a simple installation and accuracy for evaluating the control performance of a TLMD.

  • PDF

Vibration Control Performance of a Two-way Tuned Liquid Mass Damper Using Real-time Hybrid Shaking Table Testing Method (실시간 하이브리드 진동대 실험법에 의한 양방향 TLMD의 진동제어 성능평가)

  • Heo, Jae-Sung;Lee, Sung-Kyung;Park, Eun-Churn;Lee, Sang-Hyun;Kim, Hong-Jin;Jo, Ji-Seong;Cho, Bong-Ho;Min, Kyung-Won
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.18 no.5
    • /
    • pp.485-495
    • /
    • 2008
  • An experimental real-time hybrid method, which implements the vibration control of a building structure with only a two-way TLMD, is proposed and verified through a shaking table test. The building structure is divided into the upper experimental TLMD and the lower numerical structural part. The shaking table vibrates the TLMD with the response calculated from the numerical substructure, which is subjected to the excitations of the measured interface control force at its top story and sinusoidal waves input at its base. The results show that the conventional method can be replaced by the proposed methodology with a simple installation and accuracy for evaluating the control performance of a TLMD.

Detachment Rate of Fruits of Lycium chinense Mill with Vibration Characteristic (진동특성에 의한 구기자 열매의 탈과율)

  • 서정덕;허윤근;이상우
    • Journal of Biosystems Engineering
    • /
    • v.25 no.2
    • /
    • pp.151-158
    • /
    • 2000
  • Detachment rate of mature fruits of the Lycium chinense Mill with various frequency, amplitude, and shaking time using an experimental vibratory system was analyzed. The experimental vibratory system was designed such that the frequency, amplitude, and shaking time could be controlled easily. The detachment rate increased as the frequency increased at constant amplitude and increased as the amplitude increased at constant frequency. The contents of the detached immature fruit, however, also increased as the frequency and amplitude increased, which was undesirable for the detachment efficiency considering the only mature 900 rpm and amplitude of 35 m for the shaking time of three seconds.

  • PDF

Verification of Hybrid Structural Test Technique by Shaking Table Test of a Linear 2-Dimensional Frame Model (소형선형 평면뼈대모형의 진동대실험을 통한 하이브리드실험 기법의 검증)

  • Cho, Sung-Min;Choi, In-Gyu;Jung, Dae-Sung;Kim, Chul-Young
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.14 no.6
    • /
    • pp.33-43
    • /
    • 2010
  • This paper deals with the hybrid structural test technique which has been introduced and studied currently in Korea. In this study, a Mini-MOST system which was developed as a part of NEES research was modified and improved to reduce the total simulation time to half of the original system. Using the proposed system together with the 2 dimensional small steel frame specimen, the validity and efficiency of the hybrid test technique is investigated. Even though the hybrid test has been developed as an alternative to the shaking table test and has been studied and applied for a long time in several countries, no attempt has been made to compare it directly with the shaking table test. Therefore, in this study, the hybrid test results are compared with those of the shaking table test as well as with a numerical simulation for the verification of hybrid test. From the comparison and analysis of the test results, it is concluded that the hybrid test can simulate the actual seismic behavior of structural systems very accurately and it can be a good alternative to the shaking table test.

Real-Time Hybrid Shaking Table Test of a Soil-Structure Interaction System with Dynamic Soil Stiffness (동적 지반강성을 갖는 지반-구조물계의 실시간 하이브리드 진동대 실험)

  • Lee, Sung-Kyung;Min, Kyung-Won
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.20 no.2
    • /
    • pp.217-225
    • /
    • 2007
  • This paper proposes the real-time hybrid shaking table testing methods to simulate the dynamic behavior of a soil-structure interaction system with dynamic soil stiffness by using only a structure model as the physical specimen and verifies their effectiveness for experimental implementation. Experimental methodologies proposed in this paper adopt such a way that absolute accelerations measured from the superstructure and shaking table are feedback to the shaking table controller, and then the shaking table is driven by the calculated motion of the absolute acceleration (acceleration feedback method) or the absolute velocity (velocity feedback method) of foundation that is required to simulate the dynamic behavior of a whole soil-structure interaction system. The shaking table test is implemented by reflecting the dynamic soil stiffness, which are differently approximated from the theoretical one depending on the feedback methods, on the shaking table controller to calculate soil part. The effectiveness of the proposed experimental methods is verified by comparing the response measured from the test on a foundation-fixed structural model and that obtained from the experiment of a soil-interaction system under the consideration in this paper and by matching the dynamic soil stiffness reflected on the shaking table controller with that identified using the experimentally measured data.

Vibration Control of a Building Structure with a Tuned Liquid Damper Using Real-Time Hybrid Experimental Method (실시간 하이브리드 실험법을 이용한 동조액체댐퍼가 설치된 건물의 진동제어)

  • Lee Sung-Kyung;Lee Sang-Hyun;Min Kyung-Won;park Eun-Churn;Woo Sung-Sik;Chung Lan
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 2006.04a
    • /
    • pp.256-263
    • /
    • 2006
  • In this paper, an experimental hybrid method, which implements the earthquake response control of a building structure with a TLD(Tuned Liquid Damper) by using only a TLD as an experimental part, is proposed and is experimentally verified through a shaking table test. In the proposed methodology, the whole building structure with a TLD is divided into the upper TLD and the lower structural parts as experimental and numerical substructures, respectively. At the moment, the control force acting between their interface is measured from the experimental TLD with shear-type load-cell which is mounted on shaking table. Shaking table vibrates the upper experimental TLD with the response calculated from the numerical substructure, which is subjected to the excitations of the measured interface control force at its top story and an earthquake input at its base. The experimental results show that the conventional method, in which both a TLD and a building structure model are physically manufactured and are tested, can be replaced by the proposed methodology with a simple experimental installation and a good accuracy for evaluating the control performance of a TLD.

  • PDF

Simulation of the damping effect of a high-rise CRST frame structure

  • Lu, Xilin;Zhang, Hongmei;Meng, Chunguang
    • Computers and Concrete
    • /
    • v.9 no.4
    • /
    • pp.245-255
    • /
    • 2012
  • The damping effect of a Concrete-filled Rectangular Steel Tube (CRST) frame structure is studied in this paper. Viscous dampers are employed to insure the function of the building especially subjected to earthquakes, for some of the main vertical elements of the building are not continuous. The shaking table test of a 1:15 scale model was conducted under different earthquake excitations to recognize the seismic behavior of this building. And the vibration damping effect was also investigated by the shaking table test and the simulation analysis. The nonlinear time-history analysis of the shaking table test model was carried out by the finite element analysis program CANNY. The simulation model was constructed in accordance with the tested one and was analyzed under the same loading condition and the simulation effect was then validated by the tested results. Further more, the simulation analysis of the prototype structure was carried out by the same procedure. Both the simulated and tested results indicate that there are no obvious weak stories on the damping equipped structure, and the dampers can provide the probability of an irregular CRST frame structure to meet the requirements of the design code on energy dissipation and deformation limitation.

Real-time Stabilization Method for Video acquired by Unmanned Aerial Vehicle (무인 항공기 촬영 동영상을 위한 실시간 안정화 기법)

  • Cho, Hyun-Tae;Bae, Hyo-Chul;Kim, Min-Uk;Yoon, Kyoungro
    • Journal of the Semiconductor & Display Technology
    • /
    • v.13 no.1
    • /
    • pp.27-33
    • /
    • 2014
  • Video from unmanned aerial vehicle (UAV) is influenced by natural environments due to the light-weight UAV, specifically by winds. Thus UAV's shaking movements make the video shaking. Objective of this paper is making a stabilized video by removing shakiness of video acquired by UAV. Stabilizer estimates camera's motion from calculation of optical flow between two successive frames. Estimated camera's movements have intended movements as well as unintended movements of shaking. Unintended movements are eliminated by smoothing process. Experimental results showed that our proposed method performs almost as good as the other off-line based stabilizer. However estimation of camera's movements, i.e., calculation of optical flow, becomes a bottleneck to the real-time stabilization. To solve this problem, we make parallel stabilizer making average 30 frames per second of stabilized video. Our proposed method can be used for the video acquired by UAV and also for the shaking video from non-professional users. The proposed method can also be used in any other fields which require object tracking, or accurate image analysis/representation.

추출조건 및 방법에 따른 인삼내의 panaxydol과 panaxynol의 추출율 비교

  • Park, Chan-Ell;Yun, Ji-Yong;Park, Chang-Ho
    • 한국생물공학회:학술대회논문집
    • /
    • 2000.04a
    • /
    • pp.493-496
    • /
    • 2000
  • The extraction efficiencies of panaxynol and panaxydol according to extraction temperature were the highest at $80^{cdot}C$ among 65, 80, $95^{cdot}C$ with soxhlet and increased with shaking method when temperature increased from $25^{cdot}C$ to $45^{cdot}C$. The amounts of panaxynol and panaxydol were determined by gas chromatography. In time dependence of extracted amounts of panaxynol and panaxydol using shaking method, the efficiencies of panaxynol and panaxydol were increased during 12 hour. The effect of water swelling on panaxynol and panaxydol extraction efficiency using soxhlet and shaking methods, the efficiencies of panaxynol and panaxydol were decreased as swelling time was increased.

  • PDF

The Comparision of Analysis Methods in dynamic Design of Dam based on Shaking Table tests (진동대시험에 근거한 댐의 내진설계시 해석 방법의 비교)

  • Hwang, Seong-Choon;Oh, Byung-Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2005.05a
    • /
    • pp.732-737
    • /
    • 2005
  • This paper performed pseudo static analysis and dynamic analysis for CFRD and evaluated reliability with the results of Shaking Table Test. The Seismic coefficient method, modified seismic coefficient method, Newmark method of Pseudo static analysis and frequency domain response analysis, time domain history analysis of dynamic analysis were used. The analysis results were differ between analysis method, but the trends of acceleration and displacement were good agreement with the results of shaking table test.

  • PDF