numerous empirical correlations exist for the estimation of crude oil viscosities. most of these correlations are not based on the experimental and field data from iranian geological zone. in this study several well-known empirical correlations including beal, beggs, glasso, labedi, schmidt, alikhan and naseri were optimized and refitted with the iranian oil field data. the results showed that ...

Many methods have been developed for structural size and configuration optimization in which cross-sectional areas are usually assumed to be continuous. In most practical structural engineering design problems, however, the design variables are discrete. This paper proposes two efficient structural optimization methods based on the harmony search (HS) heuristic algorithm that treat both discret...

A R T I C L E I N F O AISI D2 steel, Tool wear, Workpiece surface temperature, Taguchi method, Regression analysis. Received 19 July 2012 Accepted 29 August 2012 Available online 31 December 2012 Now-a-days increasing the productivity and the quality of the machined parts are the main challenges of metal cutting industry during turning processes. Optimization methods in turning processes, consi...

Modifying stress-strain curves is one of the important topics in mechanical engineering and materials science. Real stress-strain curves should be modified after necking point as stress becomes three-dimensional after creation of throat, and consequently, equivalent stress should be used instead of axial one. Also, distribution of triple stresses across throat section is not uniform anymore, an...

in this paper, a non-isothermal two-phase flow in the cathode gas diffusion layer (gdl) of pem fuel cell is modeled. the governing equations including energy, mass and momentum conservation equations are solved by numerical methods. also, the optimal values of the effective parameters such as the electrodes porosity, gas diffusion layer (gdl) thickness and inlet relative humidity are calculated...

A complexity reduction algorithm for an H.264 encoder is proposed. Computational savings are achieved by identifying, prior to motion estimation, macroblocks that are likely to be skipped and hence saving further computational processing of these macroblocks. This early prediction is made by estimating a Lagrangian rate-distortion cost function which incorporates an adaptive model for the Lagra...