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Moe Z Win - One of the best experts on this subject based on the ideXlab platform.
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molecular communication in h diffusion
IEEE Transactions on Communications, 2020Co-Authors: Dung Phuong Trinh, Youngmin Jeong, Hyundong Shin, Moe Z WinAbstract:The random propagation of molecules in a fluid medium is characterized by the spontaneous diffusion law as well as the interaction between the environment and molecules. In this paper, we embody the anomalous diffusion theory for modeling and analysis in molecular communication. We employ $H$ - diffusion to model a non-Fickian behavior of molecules in diffusive channels. $H$ -diffusion enables us to model anomalous diffusion as the subordinate relationship between self-similar parent and directing processes and their corresponding probability density functions with two $H$ -variates in a unified fashion. In addition, we introduce standard $H$ -diffusion to make a bridge of normal diffusion across well-known anomalous diffusions such as space-time fractional diffusion, Erdelyi-Kober fractional diffusion, grey Brownian motion, fractional Brownian motion, and Brownian motion. We then characterize the statistical properties of uncertainty of the random propagation time of a molecule governed by $H$ -diffusion laws by introducing a general class of molecular noise—called $H$ -noise. Since $H$ -noise can be an algebraic-tailed distribution, we provide a concept of $H$ -noise power using finite logarithm moments based on zero-order statistics. Finally, we develop a unifying framework for error probability analysis in a timing-based molecular communication system with a concept of signal-to-noise power ratio.
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molecular communication in h diffusion
arXiv: Information Theory, 2019Co-Authors: Dung Phuong Trinh, Youngmin Jeong, Hyundong Shin, Moe Z WinAbstract:The random propagation of molecules in a fluid medium is characterized by the spontaneous diffusion law as well as the interaction between the environment and molecules. In this paper, we embody the anomalous diffusion theory for modeling and analysis in molecular communication. We employ H-diffusion to model a non-Fickian behavior of molecules in diffusive channels. H-diffusion enables us to model anomalous diffusion as the subordinate relationship between self-similar parent and directing processes and their corresponding probability density functions with two H-variates in a unified fashion. In addition, we introduce standard H-diffusion to make a bridge of normal diffusion across well-known anomalous diffusions such as space-time fractional diffusion, Erdelyi-Kober fractional diffusion, grey Brownian motion, fractional Brownian motion, and Brownian motion. We then characterize the statistical properties of uncertainty of the random propagation time of a molecule governed by H-diffusion laws by introducing a general class of molecular noise---called H-noise. Since H-noise can be an algebraic tailed process, we provide a concept of H-noise power using finite logarithm moments based on zero-order statistics. Finally, we develop a unifying framework for error probability analysis in a timing-based molecular communication system with a concept of signal-to-noise power ratio.
And Afshin Eskandari Nasrabad - One of the best experts on this subject based on the ideXlab platform.
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pair correlation functions and the self diffusion coefficient of lennard jones liquid in the modified free volume theory of diffusion
Journal of Physical Chemistry B, 2005Co-Authors: Rozita Laghaei, And Afshin Eskandari NasrabadAbstract:In this paper, we apply the Matteoli−Mansoori empirical formula for the pair correlation function of simple fluids obeying the Lennard-Jones potential to calculate reduced Self-Diffusion coefficients on the basis of the modified free volume theory. The Self-Diffusion coefficient thus computed as functions of temperature and density is compared with the molecular dynamics simulation data and the Self-Diffusion coefficient obtained by the modified free volume theory implemented with the Monte Carlo simulation method for the pair correlation function. We show that the Matteoli−Mansoori empirical formula yields sufficiently accurate Self-Diffusion coefficients in the supercritical regime, provided that the minimum free volume activating diffusion is estimated with the classical turning point of binary collision at the mean relative kinetic energy 3kBT/2, where kB is the Boltzmann constant and T is the temperature. In the subcritical regime, the empirical formula yields qualitatively correct, but lower values ...
Cherlho Lee - One of the best experts on this subject based on the ideXlab platform.
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water self diffusion in chlorella sp studied by pulse field gradient nmr
Magnetic Resonance Imaging, 2003Co-Authors: Choonghun Cho, Youngshick Hong, Kirim Kang, V I Volkov, V D Skirda, Chungyung J Lee, Cherlho LeeAbstract:The water Self-Diffusion behavior in chlorella water suspension was investigated by pulsed field gradient NMR technique. Three types of water was determined, which differs according to the Self-Diffusion coefficients; bulk water, extracellular and intracellular water. Intracellular and extracellular water Self-Diffusion were restricted, and the sizes of restriction regions were 3.4 μm and 17 μm, respectively. The water molecular exchange process between these three diffusion regions was investigated. The residence time and exchange rate constant for chlorella cells were obtained. The cell wall permeability determined from the rate constant as 3 × 10−6 m/s agreed with the permeability 10−6 m/s obtained from time dependence of intracellular water Self-Diffusion coefficient. The structural cluster model of chlorella cell is estimated to describe the extracellular water Self-Diffusion in chlorella water suspension.
Yeomin Yoon - One of the best experts on this subject based on the ideXlab platform.
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measurements of effective sizes and diffusivities of nano colloids and micro particles
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2006Co-Authors: Jaeweon Cho, Youngjun Park, Hyang Sun, Suhan Kim, Yeomin YoonAbstract:Abstract A theoretical diffusivity equation was proposed by Einstein [A. Einstein, Investigations of the Theory of the Brownian Movement, Dover Publication Inc., New York, 1956]; thermodynamic and drag (i.e., resistance or mobility relation) forces were compared at equilibrium. The diffusivity relationship, the ratio of the thermodynamic and drag forces, was combined with steady-state convection and diffusion equations to finally give a relationship between the retention times from flow field-flow fractionation (fl-FFF) and the diffusivity of a particle. An asymmetric fl-FFF system equipped with a regenerated cellulose membrane with molecular weight cutoff of 1000 and a micro channel employing both laminar channel and cross flows, was used to obtain chromatograms, using UV detection. A wide range of nano-colloids and micro-particles were measured with respect to their effective sizes and diffusivities. The classical FFF theory was incorporated with two different diffusion estimation relations: the Brownian and shear-induced diffusivities. It was found that the fl-FFF system provided similar and much lower sizes compared to absolute sizes provided by the manufacturer, for the smaller colloids (30, 60 nm), and the larger nano-colloids (90 nm and 0.2, 0.3, 0.43 and 0.5 μm) and micro-particles (0.5, 0.701, 0.993, 2, 3.1, and 8 μm), respectively. This was due to the larger nano-colloids and micro-particles being influenced by both the Brownian (the normal FFF mode) and shear-induced (the hyperlayer FFF mode) diffusions under the channel laminar and crossing flows condition within the micro channel of the fl-FFF system, which provided effective colloids and particles sizes. For all the nano-colloids and micro-particles, the fl-FFF system was able to determine the effective diffusion coefficients, irrespective of their size. For the micro-particles, the dimensionless diffusion coefficient was suggested to depend on the particle size, rather than that obtained by different methods suggested in previous works [E.C. Eckstein, D.G. Bailey, A.H. Shapiro, Self-Diffusion of particles in shear flow of a suspension, J. Fluid Mech. 79 (Part 1) (1977) 191–208; D. Leighton, A. Acrivos, Measurement of shear-induced Self-Diffusion in concentrated suspensions of spheres, J. Fluid Mech. 177 (1987) 109–131].
W Y Wen - One of the best experts on this subject based on the ideXlab platform.
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self diffusion of water ethanol and decafluropentane in perfluorosulfonate ionomer by pulse field gradient nmr
Polymer, 2001Co-Authors: X Gong, Athinodoros Bandis, A Tao, Ghirmai Meresi, Yingzi Wang, Paul T Inglefield, Alan A Jones, W Y WenAbstract:Abstract Self-Diffusion constants for water, ethanol and decafluoropentane were measured in the perfluorosulfonate ionomer NafionR using pulse field gradient proton NMR. Measurements were made as a function of concentration, temperature and diffusion time. For water, diffusion constants ranged from 10−4 to 10−7 cm2/s. A reasonable interpretation could be developed using free volume theory if the concentration was scaled by considering only the ionomeric pendant group as the accessible domain. The temperature dependence could be summarized in terms of the WLF equation. For ethanol, the Self-Diffusion constants are comparable in magnitude to those of water but the concentration dependence is stronger and the temperature dependence weaker. Free volume theory provides a poor framework for summarizing the concentration and temperature dependence of the diffusion of ethanol in Nafion. In an accompanying report, fluorine-19 spin diffusion and fluorine-19 line shape data indicate larger morphological changes in Nafion upon addition of ethanol and greater plasticization of the pendant group domain. The larger morphological changes are thought to contribute to the concentration dependence of diffusion making free volume theory inapplicable. The decafluoropentane diffusion constants appear to depend on the time scale over which the diffusion is observed. This is not true for the other two penetrants, which are considered to be primarily located in domains comprised of the sulfonate groups and side chains. The decafluropentane is likely to be located in amorphous domains composed of the CF2 groups. The dependence of the Self-Diffusion constant of the decafluoropentane on diffusion time indicates that the domain or phase supporting transport is poorly interconnected. At long diffusion times, the product of the Self-Diffusion constant and the diffusion time becomes constant which is associated with restricted diffusion.
