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Dissertations / Theses on the topic 'Active vibration reduction'

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Published: 8 June 2024
Last updated: 31 July 2025

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1

Ganguli, ABHIJIT. "Chatter reduction through active vibration damping." Doctoral thesis, Universite Libre de Bruxelles, 2005. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210980.

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The aim of the thesis is to propose active damping as a potential control strategy for chatter instability in machine tools.<p>The regenerative process theory explains chatter as a closed loop interaction between the structural dynamics and the cutting process. This is considered to be the most dominant reason behind machine tool chatter although other instability causing mechanisms exist.<p>The stability lobe diagram provides a quantitative idea of the limits of stable machining in terms of two physical parameters: the width of contact between tool and the workpiece, called the width of cut a
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2

Boffa, John. "Model Reduction of Large Structural Systems for Active Vibration Control." University of Technology, Sydney. Faculty of Engineering, 2006. http://hdl.handle.net/2100/338.

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This thesis studies the applicability of the Dynamic model reduction method that is used for direct plant order reduction in the active vibration control of large and flexible structures. A comparison of the performances between the reduced models produced by the Dynamic model reduction method and those obtained by other common model reduction methods such as the Guyan method, and the Mode-displacement method have been carried out. By using a full analytical model of a twenty storey building as the reference, each three degrees of freedom model was compared by computer simulation. The open-lo
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3

Huyanan, Satienpong. "An active vibration absorber for chatter reduction in machining." Thesis, University of Sheffield, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486712.

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In the early days of the manufacturing industry, the limiting factor in obtaining higher material removal rates was 'Chatter', an unstable cutting condition with excessive vibrations. Maximum productivity can only be obtained using the knowledge of the theory of regenerative chatter. In the era of modem manufacturing industry, where the greater quality and productivity are increasingly demanded, especially the requirement to understand and avoid chatter is even greater. The key answering to this challenge is to increase the rate of material removal while maintaining stable cutting conditions t
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4

Boffa, John. "Model reduction of large structural systems for active vibration control /." Electronic version, 2002. http://adt.lib.uts.edu.au/public/adt-NTSM20060317.113054/index.html.

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5

Gan, Zengkang. "Adaptive control of an active seat for occupant vibration reduction." Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.665426.

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Vehicle occupants are typically exposed to unpleasant whole-body vibration (WBV) for extended period of time. It is well known that the transmission of unwanted vibration to the human body can lead to fatigue and discomfort. Moreover, the unwanted vibration normally distributed in the low-frequency range has been found as the main risk factor for lower back pain and lumbago, which seriously affect the health and working performance of occupants. Thus vibration cancellation on seats has attracted considerable interest in recent years. So far, for most vehicle seats, vibration isolation is achie
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6

Martinovic, Zoran N. "Sensitivity of active vibration control to structural changes and model reduction." Diss., Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/53641.

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The analytical study presented here is concerned with by two types of sensitivity of active vibration control of large space structures (LSS). The first one required for assessing robustness, is the sensitivity of the performance and stability of the control system to changes in structure and to model reduction. The second type is the sensitivity of the optimum design of the control system to changes in the structure. This sensitivity is of interest in assessing the need for integrated structure/control design. Three direct rate feedback (DRF) control techniques are studied for a laboratory
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7

LI, MINGFENG. "ACTIVE VIBRATION CONTROL OF A GEARBOX SYSTEM WITH EMPHASIS ON GEAR WHINE REDUCTION." University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1115131866.

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8

Clements, Kristen Lynn. "Active control of an automobile suspension system for reduction of vibration and noise." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/30359.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Includes bibliographical references (p. 79-82).<br>A new method for controlling road noise transmitted through the suspension system of an automobile was developed, using a Lincoln LS automobile as the target vehicle. In this vehicle, road surface roughness generates vibrations that are transmitted into the automobile primary through a single bushing (
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9

Curtis, A. R. D. "The theory and application of quadratic minimization in the active reduction of sound and vibration." Thesis, University of Southampton, 1988. https://eprints.soton.ac.uk/52272/.

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Active sound reduction is the use of active sources of sound, that is devices which are potentially sources of sound energy, to modify a preexisting sound field in such a way that the overall effect is a reduction in sound. Until recently the most common approach in active sound control was to attempt to achieve complete cancellation of the sound. This is possible at single points but is practically impossible over an appreciable region. A more modest and practical aim is to try to reduce the sound field by as much as possible by minimizing some overall measure of the amplitude of the sound fi
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10

Becker, Jens. "Semi-active control of friction dampers and feedforward tracking control design for structural vibration reduction." Tönning Lübeck Marburg Der Andere Verl, 2009. http://d-nb.info/995846200/04.

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11

Huang, Haoyu. "A temperature controlled semi-active tuned mass damper using shape memory alloy for vibration reduction applications." Thesis, University of Bath, 2017. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.720664.

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This study developed a temperature controlled semi-active tuned mass damper (TMD) using shape memory alloy (SMA) for civil structural applications. It addressed the off-tuning issues caused by the variances in structural mass and stiffness when in service, since off-tuning of the TMD increases the structural response. The effect of in-service temperature on SMA can provide adaptive dynamic properties to TMD. Therefore, the natural frequencies can be adjusted to an optimal range. In this thesis, the material characterisation of SMA is studied through acting dynamic cyclic loading. It was found
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12

Brakna, Mohammed. "Sensor and actuator optimal location for dynamic controller design. Application to active vibration reduction in a galvanizing process." Electronic Thesis or Diss., Université de Lorraine, 2023. https://docnum.univ-lorraine.fr/ulprive/DDOC_T_2023_0152_BRAKNA.pdf.

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Les objectifs de cette thèse sont de déterminer un modèle à la fois suffisamment précis mais numériquement exploitable pour proposer des méthodologies de placement de capteurs et d'actionneurs pour le contrôle actif de vibration dans une ligne de galvanisation. La galvanisation consiste à recouvrir un métal (dans notre étude : de l'acier) par une couche protectrice de zinc qui évite la corrosion due à l'air. L'épaisseur de cette couche doit être constante pour garantir les propriétés mécaniques et l'état de surface du produit. Dans une ligne de galvanisation, la bande d'acier en mouvement est
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13

Wang, Peng. "Active vibration control in a specific zone of smart structures." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEC007/document.

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Cette recherche vise à résoudre un problème particulier du contrôle de vibration des structures intelligentes. Notre objectif est de réduire les vibrations dans une zone spécifique de la structure intelligente avec une perturbation qui couvre une large gamme de fréquences. De plus, dans cette zone spécifique, ni l'actionnement ni la détection ne sont possibles.Ici, nous faisons face à plusieurs défis principaux. Premièrement, nous devons contrôler les vibrations d’une zone spécifique de la structure, alors que nous n’avons accès aux mesures que dans d’autres zones. Deuxièmement, la large bande
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14

Beck, Benjamin Stewart. "Negative capacitance shunting of piezoelectric patches for vibration control of continuous systems." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45850.

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The ability to reduce flexural vibrations of lightweight structures has been a goal for many researchers. A type of transducer-controller system that accomplishes this is a piezoelectric patch connected to an electrical impedance, or shunt. The piezoelectric patch converts the vibrational strain energy of the structure to which it is bonded into electrical energy. This converted electrical energy is then modified by the shunt to influence to mechanical response. There are many types of shunt circuits which have demonstrated effective control of flexural systems. Of interest in this work is the
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15

Kim, Taeho, and Monika Ivantysynova. "Active Vibration Control of Axial Piston Machine using Higher Harmonic Least Mean Square Control of Swash Plate." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-199412.

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Noise emission is a major drawback of the positive displacement machine. The noise source can be divided into structure borne noise source (SBNS) and fluid borne noise source (FBNS). Passive techniques such as valve plate optimization have been used for noise reduction of axial piston machines. However, passive techniques are only effective for limited operating conditions or at least need compromises in design. In this paper, active vibration control of swash plate is investigated for vibration and noise reduction over a wide range of operating conditions as an additional method to passive no
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16

Bai, Hao. "Machine learning assisted probabilistic prediction of long-term fatigue damage and vibration reduction of wind turbine tower using active damping system." Thesis, Normandie, 2021. http://www.theses.fr/2021NORMIR01.

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Cette thèse est consacrée au développement d'un système d'amortissement actif pour la réduction des vibrations du mât d'éoliennes en cas de vent avec rafales et de vent avec turbulence. La présence de vibrations entraîne souvent soit une déflexion ultime au sommet du mât d'éolienne, soit une défaillance due à la fatigue du matériau près du bas du mât d'éolienne. De plus, étant donné la nature aléatoire de l'état du vent, il est indispensable d'examiner ce problème d'un point de vue probabiliste. Dans ce travail, un cadre probabiliste d'analyse de la fatigue est développé et amélioré en utilisa
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17

Sangili, Vadamalu Raja [Verfasser], Christian [Akademischer Betreuer] Beidl, and Stephan [Akademischer Betreuer] Rinderknecht. "Estimation and Control Methods for Active Reduction of Engine-Induced Torsional Vibration in Hybrid Powertrains / Raja Sangili Vadamalu ; Christian Beidl, Stephan Rinderknecht." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2018. http://d-nb.info/1193177944/34.

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18

Vadamalu, Raja [Verfasser], Christian [Akademischer Betreuer] Beidl, and Stephan [Akademischer Betreuer] Rinderknecht. "Estimation and Control Methods for Active Reduction of Engine-Induced Torsional Vibration in Hybrid Powertrains / Raja Sangili Vadamalu ; Christian Beidl, Stephan Rinderknecht." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2018. http://d-nb.info/1193177944/34.

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19

Min, Byung-Young. "A physics based investigation of gurney flaps for enhancement of rotorcraft flight characteristics." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33851.

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Helicopters are versatile vehicles that can vertically take off and land, hover, and perform maneuver at very low forward speeds. These characteristics make them unique for a number of civilian and military applications. However, the radial and azimuthal variation of dynamic pressure causes rotors to experience adverse phenomena such as transonic shocks and 3-D dynamic stall. Adverse interactions such as blade vortex interaction and rotor-airframe interaction may also occur. These phenomena contribute to noise and vibrations. Finally, in the event of an engine failure, rotorcraft tends to desc
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20

Farah, Philippe-Siad. "Étude de la réduction des vibrations des machines synchrones." Grenoble INPG, 1995. http://www.theses.fr/1995INPG0087.

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Ce mémoire concerne l'étude de la réduction des vibrations des machines synchrones. L'objectif est de proposer une structure optimisée au plan vibratoire, et de mettre au point un dispositif de contrôle actif des vibrations. L'essentiel des informations utiles à la compréhension des mécanismes sources de vibrations est exposé au premier chapitre. Il est montré que le caractère non sinusoïdal de l'induction dans l'entrefer est source de vibrations (électromagnétiques. L'étude expérimentale, sujet du deuxième chapitre sert à définir les éléments de conception d'une machine optimisée au plan vibr
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21

Karim, Yassine. "Caractérisation robuste de liaisons amortissantes avec dispositifs piezo-électriques pour la réduction de vibrations de structures." Phd thesis, Conservatoire national des arts et metiers - CNAM, 2013. http://tel.archives-ouvertes.fr/tel-00953330.

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L'étude présentée dans ce document a pour objet l'étude de différents modes de réduction de vibrations dans les structures avec liaisons. Le premier mode étudié se base sur la dissipation d'énergie apportée par la déformation d' éléments piézoélectriques connectés à un circuit électrique adapté. Le second mode proposé se base sur la propriété de la liaison boulonnée à changer les fréquences propres d'une structure en fonction du serrage appliqué. Cette propriété est utilisée avec plusieurs lois de contrôle du serrage afin d'éviter les plages de fréquences critiques. Ensuite une étude probabili
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22

Brinkschulte, Lars, Marina Graf, and Marcus Geimer. "Reinforcement learning: a control approach for reducing component damage in mobile machines." Technische Universität Dresden, 2020. https://tud.qucosa.de/id/qucosa%3A71113.

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This paper presents an active component damage reducing control approach for driving manoeuvres of a wheel loader. For this purpose, the front and rear axle loads will be manipulated by force pulses induced into the machine chassis via the lifting cylinders of the function drive. The associated control approach is based on the principles of Reinforcement Learning. The essential advantage of such methods against linear control approaches is that no descriptive system properties are required, but the algorithm automatically determines the system behaviour. Due to the high number of necessary tra
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23

Kartha, Satish Chandrashekhar. "Active, Passive and Active/Passive Control Techniques For Reduction of Vibrational Power Flow in Fluid Filled Pipes." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/31156.

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The coupled nature of vibrational energy flow in fluid filled piping systems makes its control and subsequent reduction a difficult problem. This work experimentally explores the potential of different active, passive and active/passive control methodologies for control of vibrational power flow in fluid filled pipes. Circumferential modal decomposition and measurements of vibrational power carried by individual wave types were carried out experimentally. The importance of dominant structural bending waves and the need to eliminate them in order to obtain meaningful experimental results has be
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24

Opfer, Holger. "Active cancellation of 3D Tollmien-Schlichting waves in the presence of sound and vibrations." Doctoral thesis, Köln : Dt. Zentrum für Luft- und Raumfahrt e.V., Bibliotheks- und Informationswesen, 2002. http://www.gbv.de/dms/goettingen/370770838.pdf.

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25

Boultifat, Chaouki Nacer. "Contrôle acoustique actif du bruit dans une cavité fermée." Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2019. http://www.theses.fr/2019IMTA0134/document.

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Cette thèse porte sur le contrôle acoustique actif (ANC) dans une cavité. L’objectif est d’atténuer l’effet d’une onde sonore perturbatrice en des points ou dans un volume. Ceci est réalisé à l’aide d’un contre-bruit généré, par exemple, par un haut-parleur. Cette étude requiert l’utilisation de modèles dynamiques rendant compte de l’évolution des pressions aux points d’intérêt en fonction des bruits exogènes. Ce modèle peut être obtenu par une identification fréquentielle des réponses point-à-point ou en utilisant le modèle physique sous jacent (équation des ondes). Dans ce dernier cas, la re
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26

Wei, Jyh-Yang, and 魏志揚. "Vibration reduction and stability analysis of H_infinite active control systems." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/54949820670691377701.

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碩士<br>國立中興大學<br>土木工程學系<br>87<br>In this study,H-infinite control algorithm is applied to reduce the structural responses under seismic loads. Two kinds of controlled outputs, named “displacement controlled output” and “energy controlled output” are presented to design the optimal controller for structures equipped with active tendon systems. The value of parameters alpha and gamma are selected based on the desired control efficiency. The decrease of alpha or increase of gamma will result in larger control forces and better effectiveness in reducing structural responses. Larger has to be sele
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27

Fu, Yu-Ting, and 傅俞婷. "Vibration Reduction of H-infinity Discrete-Time Active Control Systems with Time Delay." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/12101587003517304630.

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碩士<br>國立中興大學<br>土木工程學系所<br>98<br>In recent years, with numerous theoretical development and experimental verifications, both active and semi-active structural control systems have been accepted and implemented to control wind- or earthquake-induced vibration of buildings around the world. In addition, due to flexibility, reliability, and high speed, digital computers have been used for on-line signal processing and calculation of control forces in real-time control. Therefore, it is more logical and more realistic to formulate the control systems in discrete-time fashion prior to their impleme
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28

XUE, WEN-ZHENG, and 薛文証. "Study on the reduction of mast vibration and radar interference by active control system." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/66085440420911201966.

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29

Thakkar, Dipali. "Helicopter Vibration Reduction Using Single Crystal And Soft Piezoceramic Shear Induced Active Blade Twist." Thesis, 2005. https://etd.iisc.ac.in/handle/2005/1477.

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30

Thakkar, Dipali. "Helicopter Vibration Reduction Using Single Crystal And Soft Piezoceramic Shear Induced Active Blade Twist." Thesis, 2005. http://etd.iisc.ernet.in/handle/2005/1477.

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31

Chen, Lin-Hung, and 陳林宏. "Studies on Active and Passive Constrained Layer Damping for the Vibration Reduction of Cylindrical Shells." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/01040505749418225219.

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博士<br>國立臺灣科技大學<br>機械工程系<br>87<br>This investigation presents vibration response of cylindrical shells with passive and active constrained layer damping (CLD) treatments. The research topics include cylindrical shell with passive constrained layer damping (PCLD), active constrained layer damping (ACLD) and active control (AC). A thin shell theory in conjunction with the Donnell-Mushtari-Vlasov assumptions is employed to yield models for all cases. The assumed-mode method follows to discretize the energy expressions and subsequently yields the equations of motion. As to ACLD, it is formed from P
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32

Sangili, Vadamalu Raja. "Estimation and Control Methods for Active Reduction of Engine-Induced Torsional Vibration in Hybrid Powertrains." Phd thesis, 2018. https://tuprints.ulb.tu-darmstadt.de/9007/7/Vorlage_Dissertation_a5.pdf.

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Automotive powertrain development faces the formidable challenge of reducing fuel consumption, improving driving performance, meeting regulatory demands and satisfying customer demands. Besides powertrain hybridization, continuous optimization of the internal combustion engine (ICE) is actively pursued. Engine refinement using technologies like Miller/Atkinson cycle and Variable Compression Ratio leads to higher peak pressure values in the cylinder from the improved thermodynamic processes. This trend along with rightsizing and downspeeding of the ICE give rise to torque pulsations with higher
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33

Yang, Tzu-Hung, and 楊子弘. "The Study of Using Hybrid Shape Memory Helical Spring in the Vibration Reduction of Semi－Active Suspension Platform." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/98650449250197470740.

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碩士<br>大葉大學<br>機械與自動化工程學系<br>97<br>In this study, the natural frequency and the associated damping capacity of a platform suspended by four helical springs were investigated at different controlled temperatures. The helical spring was fabricated with multiple layers of pyro condensation polymeric sleeve wrapped outside a superelastic NiTi core which has been heat-treated into helical configuration beforehand. The dynamic characteristics of the hybrid shape-memory helical spring was first investigated experimentally. It was found that the first natural frequency of the spring can be decreased
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34

Ke, Jian-Cheng, and 柯建呈. "Development of semi-active control for vibration reduction of structural systems using Duffing-like model and magnetorheological damper." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/896d6s.

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35

Wrona, Stanisław. "Modelling and control of device casing vibrations for active reduction of acoustic noise." Rozprawa doktorska, 2016. https://repolis.bg.polsl.pl/dlibra/docmetadata?showContent=true&id=37786.

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36

Wrona, Stanisław. "Modelling and control of device casing vibrations for active reduction of acoustic noise." Rozprawa doktorska, 2016. https://delibra.bg.polsl.pl/dlibra/docmetadata?showContent=true&id=37786.

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37

Hsin-ChangLi and 李信昌. "A Study on the Characteristics and Reduction of Ground Vibrations Generated by Surface and Seismic Loads Acting on Layered Soils." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/02573003768243487832.

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博士<br>國立成功大學<br>土木工程學系碩博士班<br>101<br>This thesis investigates the dynamic characteristics of wave propagation in elastic layered soils. Both the theoretical matrix and finite element methods are employed to simulate the three-dimensional (3D) wave propagation in elastic layered soils with a harmonic point load acting on the surface. Using various multi-layer soils in which harmonic point loads act on the ground surface in the horizontal or vertical directions, these two methods are adopted to solve the steady state solutions of both horizontal and vertical displacement distributions along the
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