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We introduce a Quantum Electrodynamics (QED) approach to describe inelastic scattering processes of molecules in atomic-scale plasmonic picocavities. By solving the corresponding optomechanical dynamics, we identify nonlinear inelastic signals related to vibrational pumping, together with dynamical backaction and strong correlations of the photons emitted.
According to rotary vibration at the end of the concrete pump truck boom, analysis of the boom rotary vibration mechanism is carried out. Rigid-flexible coupling dynamics model and vibration control co-simulation model of the boom system are established. The analysis of the dynamic model solution shows that the simulation rotation vibration displacement curves at the end of the boom are coincided...
This paper describes fuzzy cooperative coevolution adaptive control which uses a common genetic algorithm to obtain the coefficients of the adaptive fuzzy regulator. The plant under consideration is multi-mass drive system with elastic couplings. A comparison between systems with fuzzy control and conventional PID-control is considered. It is shown that fuzzy method allows to suppress torsional vibrations...
For evaluation of aged concrete structure, it is expected to apply ultrasonic nondestructive measurement. Special coupling media with high viscosity made scanning difficult and the application to huge structure was not practical. Our group prototyped a couplant-free probe realizing strong acoustic coupling using high pressure due to Hertzian contact and found a potential to excite longitudinal wave...
At present, the nonlinear load of axle box bearing and the spatial coupling relationship of locomotive vehicle are seldom considered in the dynamic modeling of locomotive wheel rail system. Therefore, based on the time-varying nonlinear contact load of axle box bearing, the dynamic model of locomotive wheel space coupling is established. Finally, through the test-bed of locomotive wheelset test verifies...
In order to convert more vortex-induced vibration energy into electricity, a piezoelectric energy harvesting system using a modified circular cylinder is studied to evaluate its performance in water. The circular cylinder is often used to induce the Karman vortex street. To produce stronger and more regular vortices, a circular cylinder with a slit and concave rear surface is adopted in this paper...
Infrared (IR) imaging for rotating machinery monitoring and fault diagnosis has gained noticeable attention in recent years since it enables non-contact, on-intrusive and singlesensor based temperature measurements. However, the IR image for fault identification requires the process of artificial feature extraction, which is influenced by personal experience. And the sensitivity of the infrared image...
In this paper, the nonlinear dynamic behavior of the pre-twisted blades based on the Timoshenko beam theory has been investigated. The main purpose of the present work is to study the nonlinear dynamic response of uniform, rotating, cantilever pre-twisted blades. To this end, firstly, the coupled nonlinear equations of motion considering diverse parameters such as the hub radius, rotating velocity...
This paper presents a dimensionless characteristic indicator for automatic bearing fault diagnosis based on ensemble empirical mode decomposition (EEMD). Firstly, the bearing vibration components called the Intrinsic Mode Functions (IMFs) are obtained by EEMD. Secondly, all IMFs are selected to reconstruct a new signal according to the rule of the kurtosis greater than 3. Then the new signal is processed...
The technology of Bank-to-Turn is an important development direction of hypersonic glide vehicles' control. But there is a strong coupling between roll channel and yaw channel when the vehicle is in rolling maneuver. In this paper, a dual decoupling fusion control method is presented based on aileron-rudder cross decoupling control and model reference global sliding mode control for the problem of...
For the first time, this paper demonstrates the cancellation of nonlinear response in weakly coupled resonators. It has been observed that by working in the region where the mechanical nonlinearity of the resonators and the electrical nonlinearity of the electrostatic coupling cancel, the output current amplitudes are increased by 4x while the trend of vibration amplitude variation upon stiffness...
Here we propose and demonstrate a new type of microsphere whispering gallery mode (WGM) resonator with microsphere-microsphere coupling. The coupler consists of a microsphere attached to a single mode fiber (SMF) tip by use of UV adhesive. The microsphere-microsphere coupling system is robust, compact in size, easy in fabrication and stable in operation and has good Q-factor of 4.72×103. The WGM resonator...
Gears are used in different industries from machine and equipments manufacturing to automotive industry, from energy industry such as steam and hydraulic turbines, wind turbines to aeronautics such as helicopter and aero plane industries. There is an increasing demand for gears which work at high speeds and carry high loads, so there is more need for gear research and development activities on gear...
In this paper, coupled field analysis methods in finite element analysis software are investigated. 3D mechanical modeling software Solidworks 2011 and general finite element analysis software ANSYS Workbench 14.0 are used in combination, and two sets of sequential coupling simulation schemes containing thermal-vibration sequential coupling analysis and vibration-thermal sequential coupling analysis...
The hybridization of different quasi-particles is an extensively studied subject; both from a practical as well as fundamental point of view. The resultant hybrid excitations exhibit new properties that are not available by the isolated constituents.
Plasmonic cavities are suitable platforms for studying the interaction of light and matter at the nanoscale. It has been demonstrated that plasmonic cavities are able to squeeze light into nanometer-sized volumes and thus open novel possibilities for studying the interaction of single molecules with light. For example, it has been recently shown that off-resonance Surface-Enhanced Raman Spectroscopy...
In the dynamic test system of PMSM, the tested machine, dynamic torque meter and load machine are connected in a coaxial rotating machinery by two couplings. More than 70% of mechanical faults are caused by misalignment. The frequency response of parallel misalignment in a PMSM test bench was studied in this paper. A motion equation of shafting based on Lagrange method is established. The frequency...
The inherent advantages such as high robustness, low cost and high starting torque have made switched reluctance machine a strong candidate for electric vehicle applications. However, the serious vibration and acoustic noise are very troublesome. In this paper, a semi-analytical vibration prediction model is developed and an enhanced vibration reduction method is presented via random-varying turn-off...
This paper develops a novel fractional order model for a flexible two-mass system and proposes a fractional order controller to suppress residual vibration of this system. Based on fractional order constitutive law of viscoelastic material, a generic fractional order dynamic model has been derived for a flexible two-mass system, ranging from the pure elastic solids to the pure viscous materials. To...
Switched Reluctance Motor (SRM) presents simple construction, high starting torque, wide speed range, high efficiency and high reliability which are appropriate for an Electric Vehicle (EV) drive system. However, SRM has some issues such as high torque ripple, acoustic noise, vibration due to non-linearities, and require a position sensor for control. The purpose of this paper is to compare two different...
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