Substantial variability is seen when thickness measurements using conventional ultrasonic time of flight are carried out on rough surfaces; this makes it difficult to estimate corrosion rates the mechanism leads surface roughness. It has been shown that guided wave cut-off frequencies (through resonance frequencies) can be done at much lower than gauging for same minimum resolution. The frequen...

An Adaptative Neuro-Fuzzy Inference System (ANFIS), new flexible tool, is applied to predict the cut-off frequencies of the symmetric and the anti-symmetric circumferential waves (Si and Ai, i=1,2) propagating around an elastic aluminum cylindrical shell of various radius ratio b/a (a: outer radius and b: inner radius). The time-frequency of WignerVille and the proper modes theory are used in t...

We study the flow induced by random vibration of a solid boundary in an otherwise quiescent fluid. The analysis is motivated by experiments conducted under the low level and random effective acceleration field that is typical of a microgravity environment. When the boundary is planar and is being vibrated along its own plane, the variance of the velocity field decays as a power law of distance ...

It has been suggested that dark energy will lead to a frequency cut-off in an experiment involving a Josephson junction. Here we show that were such a cut-off detected, it would have dramatic consequences including the possible demise of the string landscape.

In this paper, drain-source current, transconductance and cutoff frequency in AlGaN/GaN high electron mobility transistors have been investigated. In order to obtain parameters of exact AlGaN/GaN high electron mobility transistors such as electron density, the wave function, band gap, polarization charge, effective mass and dielectric constant, the hydrostatic pressure and temperature effects a...

In this paper, a noise reduction technique is introduced based on the Gabor time-frequency transform. In the proposed approach, noise is removed using low pass filters locally in the transform domain. Finding the cut-off frequency for the low pass filters in such a way that image does not loose its features, is an important issue. The optimal cut-off frequency of the low pass filters are comput...

abstract to evaluate the effects of the irrigation termination in different growth stages on yield and its components of autumn’s canola cultivars in isfahan region. an experiment was conducted in 2005-2006 in kabotar abad research station. a split plot layout within a randomized complete block design with tree replication was used. main plots were seven level of the irrigation cut-off time (d1...

The objective of this paper is to simulate static I-V and dynamic characteristics of an appropriated and recessed nGaN/AlxGa1-xN/GaN high electron mobility (HEMT). Using SILVACO TCAD device simulation, and optimized technological parameters; we calculate the drain-source current (IDS) as a function of the drain-source voltage (VDS) for different values of the gatesource voltage (VGS), and the d...

in the construction process of a plastic concrete cut-off wall, concreting is usually performed using the termie pipe method. in this method, concreting is performed from the lowest point in the excavated trench (containing the slurry) using a funnel and the pipe connected to it. the concrete poured in the funnel gradually settles in the panel through the termie pipe which is beneath the slurry...