نتایج جستجو برای: permeability tensor

تعداد نتایج: 93176  

2010
Anirudh Pradhan Rekha Singh J. P. Shahi

Two new cylindrically symmetric inhomogeneous string cosmological models are investigated in presence of magnetic field. We have assumed that F12 is the only non-vanishing component of electromagnetic field tensor Fij . The Maxwell’s equations show that F12 is the function of x alone whereas the magnetic permeability μ̄ is the function of x and t both. To get the deterministic solution, it has b...

Journal: :Nature communications 2013
Zhaxylyk A Kudyshev Martin C Richardson Natalia M Litchinitser

Microwave beam transmission and manipulation in the atmosphere is an important but difficult task. One of the major challenges in transmitting and routing microwaves in air is unavoidable divergence because of diffraction. Here we introduce and design virtual hyperbolic metamaterials (VHMMs) formed by an array of plasma channels in air as a result of self-focusing of an intense laser pulse, and...

2017
W. Ross Stone Ross Stone

In an inverse scattering problem, the fields in the inhomogeneous wave equation are known, and it is desired to solve for the source term. N. N. Bojarski has recently derived an Exact Inverse Scattering Theory for such "inverse source" problems. The problem of determining the generalized refractive index (i.e., the complex permeability and dielectric constant for an electromagnetic problem, or ...

2010
Hassan Masoud Alexander Alexeev George W. Woodruff

We develop a hybrid computational method to examine the permeation and hindered diffusion through mechanically loaded (anisotropic) polymer networks. We use the bond-bending lattice spring model to capture the micromechanics of random networks of interconnected filaments coupled with the dissipative particle dynamics to explicitly model the viscous fluid and diffusive objects. Our simulations r...

Permeability can be directly measured using cores taken from the reservoir in the laboratory. Due to high cost associated with coring, cores are available in a limited number of wells in a field. Many empirical models, statistical methods, and intelligent techniques were suggested to predict permeability in un-cored wells from easy-to-obtain and frequent data such as wireline logs. The main obj...

Journal: :پژوهش های علوم و فناوری چوب و جنگل 0

in this study, medium density fiberboard (mdf), was produced by dry process using refined fibers from choob khazare caspian amol factory, with 3 levels of urea formaldehyde adhesive at 8, 10, and 12 percent, and 3 levels of paraffin at 0.5, 1, and 1.5 percent. from every treatment, cylindrical samples for permeability measurement with 13 mm in diameter, and 30 mm of height were cut using hole-s...

Journal: :iranian journal of science and technology (sciences) 2005
b. najafi

in this paper the general relatively isotropic l -curvature finsler metrics are studied. it isshown that on constant relatively landsberg spaces, the concepts of weakly landsbergian, landsbergianand generalized landsbergian metrics are equivalent. some necessary conditions for a relativelyisotropic l -curvature finsler metric to be a riemannian metric are also found.

ژورنال: ژئوفیزیک ایران 2019

Recently, interpretation of causative sources using components of the gravity gradient tensor (GGT) has had a rapid progress. Assuming N as the structural index, components of the gravity vector and gravity gradient tensor have a homogeneity degree of -N and - (N+1), respectively. In this paper, it is shown that the eigenvalues, the first and the second rotational invariants of the GGT (I1 and ...

Journal: :فیزیک زمین و فضا 0
mohammad ali shahrabi m. sc. in geophysics, department of earth physics, institute of geophysics, university of tehran, iran mohammad kazem hafizi professor, department of earth physics, institute of geophysics, university of tehran, iran hosein hashemi assistant professor, department of earth physics, institute of geophysics, university of tehran, iran pejman shahsavari m. sc. in geophysics, department of earth physics, institute of geophysics, university of tehran, iran

since hydrocarbon sources have an important role in development of industry and technology, exploration of them has been lionized by human. the seismic reflection method is one of the most applicable investigative methods to identify the hydrocarbon reservoirs, but in some cases this method does not work well because of geology conditions and wave attenuation in depth. thus, some exploration me...

2013
P. Kochunov J. Chiappelli L.E. Hong

INTRODUCTION Diffusion tensor imaging (DTI) assumes a single pool of anisotropically diffusing water to calculate fractional anisotropy (FA) and is commonly used to ascertain white matter (WM) deficits in schizophrenia. At higher b-values, diffusion-signal decay becomes bi-exponential, suggesting the presence of two, unrestricted and restricted, water pools. Theoretical work suggests that semi-...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید