This paper deals with the design and fabrication of a quartz-crystal resonator used in a thickness-monitor unit, measuring film thickness in a film-depositing system. A purpose-grown quartz crystal is cut to form the desired wafer. Two gold electrodes are deposited on both surfaces of the wafer to provide electrical contacts. The resonance frequency of the resonator, at room temperature, and th...

now a days, structures with planar geometry such as sheet metals, have attracted special consideration among advanced techno logia, and hence investing vibration behavior of sheet metal is of prim important . in particular regarding dynamical investigations, if the natural frequencies get ignored, the resonance phenomena can exert noun computing damages to the structure and systems. in this res...

it is well known that ground-shaking site effect caused by an earthquake can vary significantly within a small distance. this is because at sites having soft soil and/or topographic and basement undulations, seismic energy gets trapped, leading to amplification of vibration that may cause considerable damage to man-made structures. theoretical analysis and observational data have shown that eac...

In this study, the method of multiple scales is used to perform a nonlinear vibration analysis of a mechanical system in two cases; with dry and lubricated clearance joints. In the dry contact case, the Lankarani-Nikravesh model is used to represent the contact force between the joined bodies. The surface elasticity is modeled as a nonlinear spring-damper element. Primary resonance is discussed...

introduction radiofrequency planar microcoils are used to increase the resolution of magnetic resonance images of small samples. in this study, we aimed to design and fabricate a spiral planar microcoil constructed on a double-sided printed circuit board (pcb). it has four rings with an internal diameter of 241 microns tuned and matched at 63.8 mhz. materials and methods to achieve the maximum ...

Introduction Radiofrequency planar microcoils are used to increase the resolution of magnetic resonance images of small samples. In this study, we aimed to design and fabricate a spiral planar microcoil constructed on a double-sided printed circuit board (PCB). It has four rings with an internal diameter of 241 microns tuned and matched at 63.8 MHz. Materials and Methods To achieve the maximum ...

High-frequency coils are widely used in medical applications, such as Magnetic Resonance Imaging (MRI) systems. A typical medical MRI includes a local radio frequency transmit/receive coil. This coil is designed for maximum energy transfer or wave transfer through magnetic resonance. Mutual inductance is a dynamic parameter that determines the energy quantity to be transferred wirelessly by ele...

The most promising method for micro scale energy scavenging is via vibration energy harvesting which converts mechanical energy to electrical energy. Using piezoelectric cantilevers is the most common method for vibration energy harvesting. Changing the shape of the cantilevers can lead to changing the generated output voltage and power. In this work vibration energy harvesting via piezoelectri...