摘要：The problem of active vibration control for uncertain linear structural systems with control forces input timedelay is investigated in this ***,the original structural equation is converted to a state-space model by utilizing the matrix ***,according to the obtained model and a special Lyapunov functional,a sufficient condition is achieved for the closed-loop system to be stable with a prescribed level of disturbance ***,in terms of solving these linear matrix inequalities（LMIs）,the state-feed controller is achieved to stabilize the structural system with the performance ‖z‖2<γ‖ω‖***,by introducing the rank-1 vector to describe the system uncertainties,the uncertain system description is obtained,and the stabilizing condition is extended to the uncertain ***,examples are given to show the effectiveness of the proposed methods.

摘要：Traditional passive vibration absorbers are effective only when their natural frequencies are close to those of the excitations. To solve this problem, a vibration absorber with time-delayed feedback control is proposed to suppress vibration of the primary system under excitation with changing frequency. Firstly, the mechanical model of the delay coupled system is established. Then, the displacement transfer ratio of the system is obtained. The stability of the system is analyzed since delay may result in destabilization. Next, in order to design the control parameters, the vibration absorption performances of the proposed time-delayed vibration absorber are studied. The vibration absorption region is shown. The results show that time-delayed feedback control is able to change the response of the system. The effective vibration absorption frequency band is adjustable by tuning the control gain and time delay. The effective frequency band can be widened when choosing appropriate control parameters. The vibration absorption performances can be greatly improved by the time-delayed absorber. In addition, the optimum control parameters are obtained. Finally, the experimental prototype is constructed. Several tests with different control parameters are taken. The experimental and analytical results match quite well.

摘要：vibration energy harvesting is a promising approach for sustainable energy generation from ambience to meet the development of self-powered ***,we propose a novel compact non-resonant magnetically modulated rotational energy harvester(MMR-EH)for low frequency and irregular *** the rational arrangement of multiple magnetic fields in space,a ring route with low potential energy is established.A movable magnet can be non-contact modulated by the magnetic force to move along the ring route under irregular vibration,which is instrumental in electromechanical energy conversion.A dynamic model of the MMR-EH is developed based on the energy method and verified *** effects of key parameters on the magnetically modulated route are *** simulation and experimental results demonstrate that the MMR-EH can effectively harvest the energy from ultra-low frequency(3 Hz)and irregular *** a reciprocating vibration frequency of 10 Hz and an amplitude of 20 mm,the harvester can produce an average power of 0.29 mW.

摘要：Longitudinal and horizontal vibration must both be reduced in an effective vibration isolation system. We present a cylindrical shell vibration isolator as a dynamic system composed of four springs and dampers. vibration is directly produced by the motion of machinery, and more is subsequently generated by harmonic frequencies within their structure. To test the effectiveness of our isolator, we first determined equations for the transmission of vibration from the machine to its cylindrical shell. Damping effects produced by the vibration parameters of our system are then analyzed.

摘要：The double drum coal shearer is widely applied for the underground coal exploration in the mining *** vibration and noise control are significant factors for the stability design of the double drum coal *** this paper,the vibration properties of a double drum coal shearer are firstly *** horizontal,transverse and torsional vibrations of the motor body and the angle displacements of the rockers are taken into *** walking units and the hydraulic units are modeled by the stiffness-damping *** nonlinear equation of motion of the double drum coal shearer is established by applying the Lagrange’s *** nonlinear vibration response of the system is calculated by using the Runge Kutta numerical *** effects of the shearing loads,the equivalent damping and stiffness of the walking units,the inclination angels of the rockers and the equivalent damping and stiffness of the hydraulic units on the vibration properties of the system are discussed.

摘要：A device for superimposing vibration on workpiece in both horizontal and vertical directions during tungsten-arc inert gas （TIG） welding was developed, with maximum power output of 2 kW at frequency of 15 kHz. AZ31 sheets with thickness of I and 3 mm were used in the vibratory welding. Microstructures along with the mechanical properties of the weld joints under different vibrating conditions （vibration direction, vibration amplitude and groove angle） were examined. It is observed that the grain size in welding zone decreases remarkably with the application of vibration, while the amount of second phase β-Mg_17Al_12 within the zone decreases slightly; meanwhile, microhardness of the weld joints, macroscopic tensile strength and elongation of the weldment increase. vibration, especially the one along vertical direction, has more impact on the performance of the thick weldments. Influence of vibration on mierostructure and mechanical properties of weldments is affected by wave energy transferring in the melt and depends on the processing and geometric parameters including amplitude and direction of vibration, thickness, and groove angles.

摘要：Limited by the writing habits of the small tradition, conventional scholars tend to interpret "golden sound and jade vibration" as a musical tempo representing virtues of saints. In fact, we can prove how "golden sound and jade vibration" are closely linked to the sacred material beliefs (e.g.,"holy gold","holy jade") and the prehistoric religious ritual activities, by using various oral cultures and physical images, deeply exploring the profound cultural roots of "golden sound" and "jade vibration" in the local knowledge tradition and tracing its genetic system back to the prehistoric Jade Age and Bronze Age. The concept of "golden sound and jade vibration" is the sacred aural symbol of the "sage" entering the imaginary and illusionary realm. It also highlights the genetic system of the sage having "great accomplishments" and the Chinese ritual music system.

摘要：In this paper a simplified approach to optimize the design of Shell Tube Heat Exchanger [STHE] by flow induced vibration analysis [FVA] is presented. The vibration analysis of STHE helps in achieving optimization in design by prevention of tube failure caused due to flow induced vibration. The main reason for tube failure due to flow induced vibration is increased size of STHE. It is found that in case of increased size of STHE, the surface area and number of tubes increases, thus the understanding and analysis of vibration becomes a very difficult task. Again it is found that flow induced vibration analysis is considered as an integral part of mechanical & thermal design of STHE. The detailed design, fabrication, testing and analysis work was carried out at Alfa Laval (India), Ltd., Pune-10.

摘要：This paper deals with the design, modeling and analysis of implementing a Multilayer Piezoelectric vibration Energy Harvesting (ML PZT VEH) Mechanism in the vehicle suspension. The principle of work of the proposed ML PZT VEH mechanism is reducing the relative motion of the suspension, amplifying the applied force to the PZT by a specific design of mechanism and combining a single layer PZT into multilayer PZT to increase the produced electricity. To maintain the performance of suspension as the original suspension, the ML PZT VEH mechanism is mounted in series with the spring of the suspension. The proposed ML PZT VEH mechanism and its implementation to the vehicle suspension were mathematically modeled. Responses of the vehicle before and after implementing ML PZT VEH mechanism were simulated. The results show the proposed mechanism can produce output voltage of 2.75 and power of 7.17 times bigger than direct mounting to the vehicle suspension. And the simulation result shows that mounting ML PZT VEH mechanism in series with the spring of the vehicle suspension does not change the performance of suspension.

摘要：A piezoelectric sensor charge/voltage conversion circuit is designed based on the principle that piezoelectric sensor can convert the vibration or shock acceleration into the charge *** of temperature characteristic of feedback capacitor on the switching circuit output is analyzed based on the acquisition and measurement system in this *** characteristics of different filters are analyzed,and the corresponding filter circuit is configured according to the actual sensor *** show that the circuit can effectively filter out noises among the vibration signal and obtain vibration signal accurately.