The plasma source can restrict the motion of charges that are localizing in the non equilibrium distribution of charge energy and reducing the electrons transport across magnetic field . The electrons & ions motion are controlled by ambipolar electric field and charge–atom collision . the source density for a given electron temperature and a given ion are considered to evaluate the diffusion coefficient . the ambipolar diffusion coefficient and the cross field diffusion coefficient for charge transfer are calculated through magnetized plasma in a uniform magnetic field , and an approximation ambipolar diffusion coefficient is evaluated. The result, showes how the diffusion process is gradually imbedded as the properties of the plasma.
Charge Transport in Magnetized Plasma
Change transport
monetized plasma
diffusion coefficient
Publication Date
Wed Jan 01 2020
Journal Name
Technologies And Materials For Renewable Energy, Environment And Sustainability: Tmrees20
Change detection of the land cover for three decades using remote sensing data and geographic information system
The changes in the land cover using geographical information systems and remote sensing techniques for the period (1990 - 2019) for part of the Baghdad governorate in central Iraq are detected and monitored. In this research
four satellite scenes with different sensors were used the TM
ETM+
and OLI
which were obtained by Landsat-5
Landsat-7 and Landsat-8 satellites
respectively. Maximum likelihood method supervised classification is adopted as the main classifier to distinguish different land cover types in the study region. The results showed that there are ten different classes in the values of their reflectance. This study proved that any landcover of the earth’s surface can be studied and determined by its spectral characteristics. The change for each class of the land cover for the study area was determined within the study period. The results of the study confirmed the possibility of identifying the types of land cover and finding the percentage of changes that occur in it and detecting it with high efficiency using the remote sensing technique.
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Publication Date
Fri Mar 01 2019
Journal Name
Applied Acoustics
Theoretical model of absorption coefficient of an inhomogeneous MPP absorber with multi-cavity depths
Micro-perforated panel (MPP) absorber has been known as an alternative absorber to classical porous material given its facile installation
long durability
environmental friendliness and attractive appearance. Extensive studies of MPP absorber proposing the improvement of its absorption frequency bandwidth have been published. This study presents a MPP absorber introduced with inhomogeneous perforations and with multi-cavity depths. The MPP is divided into two sub-area
where each area has different hole diameter
perforation ratio and a separated backed cavity depth. The acoustic impedance is modelled using electrical equivalent circuit and the absorption coefficient is calculated under normal-incidence of sound. It is found that the inhomogeneous MPP can have good bandwidth of absorption by designing the sub-MPP of smaller perforation ratio with large hole diameter and the one having the larger perforation ratio with smaller hole diameter. The absorption bandwidth can be conveniently controlled by adjusting the cavity depth of each sub-MPP. The results from the experimental work show good agreement with the theoretical model.
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