A two-dimensional (2-D) finite element model (FEM) has been developed to perform numerical simulations of vibration assisted machining (VAM). The model is based on an updated Lagrangian formulation, with adaptive remeshing. The model is capable of simulating the amplitude and frequency independently of the tool in the cutting (x) and thrust (y) force directions over a wide range of values. The ...

From density-functional calculations, we show that localized states stemming from defects or topological disorder exhibit an anomalously large electron–phonon coupling. We provide a simple analysis to explain the observation and perform a detailed study on an interesting system: amorphous silicon. We compute firstprinciples deformation potentials (by computing the sensitivity of specific electr...

The thermal conductivity of disordered silicon-germanium alloys is computed from density-functional perturbation theory and with relaxation times that include both harmonic and anharmonic scattering terms. We show that this approach yields an excellent agreement at all compositions with experimental results and provides clear design rules for the engineering of nanostructured thermoelectrics. F...

This work describes an on-chip integrated micro-actuator device for slack-free carbon nanotube (CNT) resonators, improving frequency tunability and Q factor and to study non-linear mode interaction. The device fabricated on SOI wafer with low thermal budget (<600 K) encompasses a restricted symmetrical out-of-plane vibration and a stiff in-plane electro-thermal actuator with a displacement of ~...

Thermal conductivity of a s10,10d carbon nanotube filled with C60 fullerenes (or a peapod) is computed using direct molecular-dynamics simulations with the Tersoff-Brenner potential for C-C bonding interactions and the van der Waals potential for nonbonding interactions. The temperature-dependent thermal conductivity of the peapod, while showing qualitatively similar behavior to that of an unfi...

9.1 Harmonic Oscillator 9.1.1 Classical harmonic oscillator and h.o. model 9.1.2 Oscillator Hamiltonian: Position and momentum operators 9.1.3 Position representation 9.1.4 Heisenberg picture 9.1.5 Schrödinger picture 9.2 Uncertainty relationships 9.3 Coherent States 9.3.1 Expansion in terms of number states 9.3.2 Non-Orthogonality 9.3.3 Uncertainty relationships 9.3.4 X-representation 9.4 Phon...

It had been observed that the mechanical stability of some magnets had influences on the closed orbit in the storage ring. In this paper, a mechanical shaker in low vibration level was applied on the quadrupole magnet. The perturbation of the closed orbit was measured. The thermal induced distortion of magnet supporting structure was discussed. The motions of BPM and quadrupole magnet were meas...

Scanning probe microscopes are notoriously susceptible to disturbances, or mechanical noise, from the surrounding environment that couple to the probe–sample interaction. These disturbances include vibrations of mechanical components, piezo drift, and thermal expansion. Disturbance effects can be substantially reduced by designing a rigid microscope, incorporating effective vibration isolation,...

We have experimentally determined the elastic properties of an individual multi-wall boron nitride (BN) nanotube. From the thermal vibration amplitude of a cantilevered BN nanotube observed in a transmission electron microscope, we find the axial Young's modulus to be 1.22 ± 0.24 TPa, a value consistent with theoretical estimates. The observed Young's modulus exceeds that of all other known ins...

Rotor cage faults as broken rotor bars, increased bars resistance and end-ring faults can be caused by thermal stresses, due to overload, overheating and thus mechanical stresses, magnetic stresses and dynamic stresses due to shaft torques. Environmental stresses as contamination or abrasion also contributes to the rotor cage faults. The rotor cage faults can also lead to the shaft vibration an...