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Channel Flow and Flood Estimate

References [1] J. A. Adegoke and G. B. Egbeyale, A computation of laminar flow in open channels and its application to sheet erosion, African Journal of Physical Science 4(1) (2011), 91-100. [2] Th. M. Boers, Rainwater Harvesting in Arid and Semi-arid Zones, Wageningen, The Netherlands, International Land Reclamation and Improvement Institute (ILRI), 1994, 132. [3] M. G. Bos, Discharge Measurement Structures, International Institute for Land Reclamation and Improvement, 2nd ed., Wageningen, 1978. [4] V. J. Boussinesq, Memoir on the

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Fluid Flow Control in Domestic Hot Water Systems During Days with Different Radiative Stability Levels

References [1] S. Furbo, I. J. Shah. Optimum solar collector fluid flow rate, Proceeding of Eurosun , Department of Building and Energy (1996) 996 [2] L. M. Nhut, Y. C. Park. A study on automatic optimal operation of a pump for solar domestic hot water system Solar Energy 98 (2013) 448-457 [3] T. Persson, M. Ronnelid. Increasing solar gains by using hot waterto heat dishwashers and washing machines Applied Thermal Engineering 27 (2007) 646-657 [4] V. Badescu. Optimal control of flow in solar collector systems with fully mixed water

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Neural Flows in Hopfield Network Approach

Abstract

In most of the applications involving neural networks, the main problem consists in finding an optimal procedure to reduce the real neuron to simpler models which still express the biological complexity but allow highlighting the main characteristics of the system. We effectively investigate a simple reduction procedure which leads from complex models of Hodgkin-Huxley type to very convenient binary models of Hopfield type. The reduction will allow to describe the neuron interconnections in a quite large network and to obtain information concerning its symmetry and stability. Both cases, on homogeneous voltage across the membrane and inhomogeneous voltage along the axon will be tackled out. Few numerical simulations of the neural flow based on the cable-equation will be also presented.

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Simulations Of Air Flow Over A Parabolic Antenna

Abstract

In this paper it is present the influence of the wind on a parabolic antenna, in order to study this influence it was made simulations of air flow over a parabolic antenna. The simulations are made with antenna positioned at 90°, 135°. A three – dimensional finite element is simulated for determination of the antenna displacement.

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Effectiveness of GEANT4 in Monte Carlo Simulation Studyofphonon Conduction in Sn Host with Si Nanowire Interface

Abstract

We have explored the effectiveness of Geant4 by using it to simulate phonon conduction in Sn Host with Si Nanowire Interface. Our Monte Carlo Simulation shows that the effectiveness of the phonon conduction Geant4 simulation increases when the system attained a steady state of 100 time steps. We have simulated phonon conduction in Sn host with Si nanowire interface using a Geant4Condensed Matter Physics Monte Carlo simulation toolkit in a low cost and less powerful processing computer machine. In the simulation, phonons were displaced inside a computation domain from their initial positions with the velocities and direction vectors assigned to them. A time step was selected so that a phonon can move at most the length of one sub-cell in one time step. Our phonon conduction analysis of SiSn based alloy using Geant4 showed performance enhancement and reasonable predicted thermal values. Numerical predictions of the thermal profile simulations of the values of the temperature in each cell were all within ten percent of the average temperature of Silicon – Tin.

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Influence of Mechanical Stirring on the Crucible Dissolution Rate and Impurities Distribution in Directional Solidification of Multicrystalline Silicon

Abstract

In this study, time dependent three-dimensional numerical simulations were carried out using the STHAMAS3D software in order to understand the effects of forced convection induced by mechanical stirring of the melt, on the crucible dissolution rate and on the impurities distribution in multicrystalline silicon (mc-Si) melt for different values of the diffusion coefficient.

Numerical simulations were performed on a pilot scale furnace with crucible dimensions of 38x38x40cm3. The computational domain used for the local 3D-simulations consists of melt and crystal.

The dissolution rate was estimated from the total mass of impurities that was found in the silicon melt after a certain period of time. The obtained results show that enhanced convection produced by a mechanical stirrer leads to a significant increase of the dissolution rate and also to a uniform distribution of impurities in the melt.

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Nonthermal Argon Plasma Generator and Some Potential Applications

Abstract

A laboratory - made nonthermal plasma generator is presented. It has a diameter of 0.020 m and length of 0.155 m and contains two electrodes. The first electrode is a 2% Th-W alloy, 0.002 m in diameter bar, centred inside the generator’s body by means of a four channel teflon piece; the other three channels, 0.003 m in diameter, are used for Ar supply. The second electrode is a nozzle of 0.002 m - 0.008 m diameter and 0.005m length. A ~500 kV/m electric field is generated between the two electrodes by a high frequency source (13.56 MHz ±5%), equipped with a OT-1000 (Tungsram) power triode. For Ar flows ranging from 0.00008 m3/s to 0.00056 m3/s, a plasma jet of length not exceeding 0.015 m and temperature below 315 K is obtained. Anthurium andraeanumis sample , blood matrix, human hair and textile fibers may be introduced in the plasma jet. For time periods of 30 s and 60 s, various effects like, cell detexturization, fast blood coagulation or textile fiber or hair cleaning and smoothing are obtained. These effects are presented and discussed in the paper.

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