We consider algorithms for finding the optimal location of a simple transportation device, that we call a moving walkway, consisting of a pair of points in the plane between which the travel speed is high. More specifically, one can travel from one endpoint of the walkway to the other at speed v > 1, but can only travel at unit speed between any other pair of points. The travel time between any...

Genetic transformation is a natural process during which foreign DNA enters a cell and integrates into the genome. Apart from its relevance for horizontal gene transfer in nature, transformation is also the cornerstone of today's recombinant gene technology. Despite its importance, relatively little is known about the factors that determine transformation efficiency. We hypothesize that differe...

In this paper, we have used a control volume method to investigate the problem of a fully coupled fluid flow with heat transfer in a rectangular domain with slip wall boundary conditions. We have used this method to solve the governing equations and thereby to compute the convective and diffusive fluxes at the cell faces of the control volumes considered around the grid points of computational ...

A three-level relief chain including a number of suppliers in fixed locations, candidate distribution centers and affected areas at certain points are considered. A mixed integer nonlinear programming model is proposed for open transportation location routing problem by considering split delivery of demand. To solve a realistic problem, foregoing parameters are considered as fuzzy in our propos...

Shell and Tube heat exchangers are the heat exchangers that are most widely used in industries and for other commercial purposes. There are many techniques that have been utilized to enhance the heat transfer performance of the shell and tube heat exchangers. Air bubble injection is one of the promising and inexpensive techniques that can create turbulence in the fluids resulting in to enhancem...

Introduction: About 50 to 70 percent of the waste management total cost is spent on collection operations, so any little progress in reducing collection costs could significantly reduce total costs. This study aimed to analyze the collection and transportation of municipal solid waste cost in Yazd in the next 15 years. Materials and Methods: The study location (five areas) was different urban ...