recent tendencies in concrete technology have been towards to high- performance concrete with a low water-cement ratio. however, high performance concretes have some problems. one of the problems is early-age cracking due to autogenous shrinkage. this study presents the results of an experimental investigation carried out to evaluate the autogenous shrinkage of high-strength concrete. accordin...

This paper investigates the effect of ethanol-unleaded gasoline blends (E0,E10,E25,E35,andE65) computer interfaced, four-stroke single cylinder compression ignition engine. The said engine wasconverted to spark ignition and carburetion to suit ethanol fuel. A suitable provision was provided on theengine to vary the compression ratio thereby making the engine adaptable to operate at lowercompres...

This study numerically investigated heat transfer and fluid flow characteristics in a novel cylindrical heat sink with helical minichannels for the laminar flow of fluid with temperature-dependent properties. A finite volume method was employed to obtain the solution of governing equations. The effects of helical angle, channel aspect ratio, and Reynolds number, which were regarded as main para...

avoid interference from secondary users to primary holders with license in spectrum, it is need to have an appropriate spectrum sensing. In methods like spectrum sensing, where samples of noise are correlated, the impairments from independent noise samples do not provide optimum performances. So, in case of random signals over a weakly correlated noise model in fading channels requires a locall...

Theoretical and practical aspects of diagonal algebraic space-time block codes over n transmit and m receive antennae are examined. The output signal-to-noise ratios of two pre-decoding filters and two decoding algorithms are derived. Analysis of the information loss incurred by using the codes considered is used to clarify their structures, and the expected performances. Different algebraic re...