One of the principal objectives of vibration isolation technology is to isolate sensitive equipment from a vibrating structure or to isolate the structure from an uncertain exogenous disturbance source. In this paper, a dynamic observer-based active isolator is proposed that guarantees closed-loop asymptotic stability and disturbance decoupling between the vibrating structure and isolated struc...

Quantum mechanics of a damped vibrating string investigated by its coupling with an infinit number of Klein-Gordon fields as environment by introducing a minimal coupling method. Heisenberg equation containing a dissipative term proportional to velocity obtained, quantum dynamics for such a dissipative system investigated. Some kinematical relations for a damped vibrating string by eliminating ...

The two limits for modeling vibrating thin films, viz as a plate or as a membrane, are discussed. In terms of these limits the sources of experimental uncertanties are identified and the advantages of using films which can be modeled as membranes are explained. The mathematical formalism for treating films as vibrating membranes is developed and relations for self-consistency checks are present...

We report a case of bilateral chronic subdural hematoma (CSDH) in a 75-year-old man after exercise using a vibrating belt machine on the head. He suffered from headache and intermittent left side numbness for ten days. He denied any head injuries except eccentric exercise using a vibrating belt on his own head for 20 days. An MRI revealed bilateral CSDH. The hematoma was isodense on the CT scan...

1 Background We begin by recalling the solution of the vibrating string problem and Sturm-Liouville problems. When we solve the problem of the vibrating string using the technique of separation of variables, the differential equation involving the space variable x, and assuming constant mass density, is y (x) + ω 2 c 2 y(x) = 0, (1.1) which we can write as an eigenvalue problem y (x) + λy(x) = ...

Low-frequency sound radiation from vibrating plates is a practical problem often found in engineering applications. In this article, the sound radiation from a circular hatchway is examined using a discrete approach based in the acoustic resistance matrix. Since this matrix can be combined with the volume velocity vector on the discretized vibrating circular surface, the sound radiation efficie...

Corrosion behavior of epoxy-coated rebar with different size microdefects in uncarbonated/carbonated simulated pore solution (U/CSPS) seawater concrete was investigated. Specimens both solutions underwent two stages corrosion, according to the electrochemical impedance spectroscopy (EIS) response. The initial stage extension corrosion. second dominated by diffusion process, due corrosion produc...

This paper describes an analytical and experimental investigation of the property of modal disparity in a vibrating structure. For a given structure, the concept of modal disparity describes the structure’s ability to generate significant changes in the mode shapes by some type of on-the-fly structural modification. In the present study we consider a vibrating beam that experiences a controlled...

To comply with recent international trends and initiatives, and in order to help achieve sustainable development, Korea has established a greenhouse gas (GHG) emission reduction target of 37% (851 million tons) of the business as usual (BAU) rate by 2030. Regarding environmentally-oriented standards such as the IGCC (International Green Construction Code), there are also rising demands for the ...