waterwheels are the oldest types of hydraulic machines. these turbines are of relatively simple design, large diameter, low rotational speed and high torques. but applying them as micro hydros of high speed and small diameter is yet to be explored. a micro hydro waterwheel of one meter diameter was designed and manufactured at the iranian  esearc†h organization for science and technology (irost...

Packet buffering in high speed routers requires a memory management unit to maintain the structure of the queues. With the dramatic increase in link speed and number of traffic flows, per-flow queuing becomes more and more challenging for the memory management unit since millions of queues should be maintained. To address this issue, a scheme called Dynamic Queue Sharing (DQS) is proposed in th...

Round Trip Time (RTT) estimation is an important variable for efficient fairness bandwidth flows of different RTT. This paper propose a stabilized rate scheme to enhance the RTT fairness on high speed Transmission Control Protocols (TCP) namely BIC-TCP, FAST, H-TCP and LTCP. The rate of window growth is stabilized in high speed protocols from the current window size, such that competing flows a...

In this paper, an unified high-order algorithm for all speeds is developed. The preconditioning matrix of Weiss and Smith combined with a 5th-order WENO scheme for inviscid flux and a fully conservative 4th order central differencing for viscous terms are employed. The unfactored implicit Gauss-Seidel relaxation scheme is used for time marching. The numerical simulation of a natural convective ...

Direct numerical simulation (DNS) is used to study the effect of individual (hemispherical) and distributed roughness on supersonic flat plate boundary layers. In both cases, roughness generates a shear layer and counter–rotating pairs of unsteady streamwise vortices. The vortices perturb the shear layer, resulting in trains of hairpin vortices and a highly unsteady flow. Mach 3.37 flow past a ...

In this study, the effect of management entrenchments on the speed of cash holding adjustment in Iran has been investigated. After designing the management entrenchment evaluation indicators, the transaction information was collected from the Stock Exchange in the five-year period of 2011-2015. The statistical sample consists of 155 companies selected by systematic deletion method. In this rese...

0301-9322/$ see front matter 2014 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ijmultiphaseflow.2013.12.007 ⇑ Corresponding author. Tel.: +1 515 294 1614; fax: +1 515 294 3262. E-mail addresses: [email protected] (J.D. Regele), jason.rabinovitch@caltech. edu (J. Rabinovitch), [email protected] (T. Colonius), [email protected] (G. Blanquart). J.D. Regele a,⇑, J. Rabi...

Counting the number of flows present in network traffic is not trivial, given that the naive approach of using a hash table to track the active flows is too slow for the current backbone network speeds. Several algorithms have been proposed in the recent literature that can calculate an approximate count using small amount of memory and few memory accesses per packet. Fewer works have addressed...

This paper describes a three-dimensional Eulerian-Lagrangian method for the modeling and simulation of high-speed multi-material dynamics. The equations for conservation of mass, momentum, and energy are solved on a fixed Cartesian grid using a fully conservative higher order MUSCL scheme. The dilatational response of each material is handled using a suitable equation of state. The embedded int...