laminar free convection heat transfer from vertical and inclined arrays of horizontal isothermal cylinders in air was investigated experimentally and numerically. experiments were carried out using mach-zehnder interferometer and the fluent code was used for numerical study. investigation was performed for vertical and horizontal cylinder spacing from 2 to 5 and 0 to 2 cylinder diameters respec...

Drivers in urban neighborhoods who patrol streets, seeking inexpensive on-street parking create a significant fraction of measured traffic congestion. The pool of drivers patrolling at any time can be modeled as a queue, where ‘queue service’ is the act of parking in a recently vacated parking space and queue discipline is SIRO – Service In Random Order. We develop a queueing model of such driv...

in this article the influence of the equipped playgrounds has been compared with natural playgrounds. playing and moving are the main activity in a young child’s life. allowing children to experience the natural and man-made elements in their living environment generates cognitive and social skills development and increases their educational qualities. today, in iran most spaces for children’s ...

Information retrieval systems typically weight the importance of search terms according to document and collection statistics (such as by using tf idf scores, where less common terms are given higher weight). We consider here the scenario where a user can express her own subjective weighting of the importance of the terms that form the query on top of the system-generated weighting, and show ho...

We present simulations of atmospheres of Earth-like aquaplanets that are tidally locked to their star, that is, planets whose orbital period is equal to the rotation period about their spin axis, so that one side always faces the star and the other side is always dark. Such simulations are of interest in the study of tidally locked terrestrial exoplanets and as illustrations of how planetary ro...

as it rises in b to enter c above the midline, etc. It can be easily seen that a similar oscillation about the midline takes place in the rotating fluid annulus of Figure 4a and in the more general situation of Figure 4b. These oscillations can be made quite small by adjusting the density of the buffer to match the particle density and by speeding up the rate of buffer flow to shorten the perio...

Several factors can influence the process of biogas production. The type of reactor is one of the key factors that influence biogas production. Therefore, the aim of this study was to construct a portable horizontal polyethylene-based biogas reactor. In addition, the performance of the developed biogas reactor was tested through digestion of cow manure. The experiments were carried out in Mashh...