Free spans or suspended spans normally occur in subsea pipelines due to the irregularity of seabed and byscouring phenomena around the installed non-buried pipeline. The hydrodynamic around the pipeline canlead to a vibration of the pipeline.This kind of vibration may cause fatigue damage to the pipeline. In orderto study the hydrodynamic around the pipeline, calculating the natural frequency o...

The present study investigated the impact of environmental pollution, represented in soil,irrigation water and air heavy metals, on the growth and production of Egyptian clovercultivated at south Greater Cairo, Egypt. Plants were sampled through five quadrats (0.5×0.5m), distributed equally in four cultivated farms in unpolluted and polluted sites, at theharvesting time. In addition, soil, air ...

local site conditions have a strong effect on ground response during earthquakes. two important soil parameters that control the amplification effects of seismic motions by a soil column are the soil hysteretic damping ratio and shear wave velocity. this paper presents the results of in situ damping ratio measurements performed using continuous surface wave attenuation data at a site in semnan ...

the objective of this research is to represent applicability of surface nuclear magnetic resonance (snmr) in aquifer characterization, based on snmr and electrical resistivity tomography data. snmr is the only geophysical method that directly detects water. two important parameters, porosity and permeability are available through inversion of initial amplitude and decay time constant versus pul...

measurement of magnitude and frequency of the voltage flicker is very important for monitoring andcontrolling voltage flicker efficiently to improve the network power quality. this paper presents twonew methods for measurement of flicker signal parameters using shuffled frog leaping algorithm(sfla) and imperialist competitive algorithm (ica). this paper estimates fundamental voltage andflicker ...