The centre of pressure (COP) movement during stance maintenance on a stable surface is commonly used to describe and evaluate static balance. The aim of our study was to test sensitivity of individual COP parameters to different stance positions which were used to address size specific changes in the support surface. Twenty-nine subjects participated in the study. They carried out three 60-seco...

We fabricated sub-THz oscillators using resonant tunneling diodes integrated with slot antennas. Oscillations at 90GHz and 136GHz were obtained for the slot antennas with the lengths of 1mm and 800μm. Theoretical calculation shows that the maximum oscillation frequency up to ~1.2THz is expected in this structure with short antenna.

The radio frequency response of InAs nanowire array transistors on mechanically flexible substrates is characterized. For the first time, GHz device operation of nanowire arrays is demonstrated, despite the relatively long channel lengths of ∼1.5 μm used in this work. Specifically, the transistors exhibit an impressive maximum frequency of oscillation, f(max) ∼ 1.8 GHz, and a cutoff frequency, ...

Physiological and clinical studies have shown that the standard method of measuring respiratory impedance by forced oscillation leads to less efficient control of the upper airway shunt effect than the head generator method. To test the effects of these two techniques in epidemiological studies, we compared, in a sample of 73 French agricultural workers, the values obtained with each method for...

We consider periodic solution for coupled systems of mass-spring. Three practical cases of these systems are explained and introduced. An analytical technique called Parameter Expansion Method PEM was applied to calculate approximations to the achieved nonlinear differential oscillation equations. Comparing with exact solutions, the first approximation to the frequency of oscillation produces t...

Overhead transmission lines are influenced by different factors which are mostly electrical and mechanical. These factors can cause problems for lines, distortions in network and outage of line. In designing transmission lines mechanical properties are evaluated after selecting a suitable conductor and clearance with regard to electrical properties. In lines designing, an important mechanical p...

different methods for detecting broken bars in induction motors can be found in literature. many of these methods are based on evaluating special frequency magnitudes in machine signals spectrums. current, power, flux, etc are among these signals. frequencies related to broken rotor fault depend on slip. in industrial environment due to some phenomena - such as load oscillation, other faults an...

Graphene devices for radio frequency (RF) applications are of great interest due to their excellent carrier mobility and saturation velocity. However, the insufficient current saturation in graphene field effect transistors (FETs) is a barrier preventing enhancements of the maximum oscillation frequency and voltage gain, both of which should be improved for RF transistors. Achieving a high outp...