Browsing by Author "Aun Haider"

Now showing 1 - 3 of 3
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    Effect of heat sink/source on peristaltic flow of jeffrey fluid through a symmetric channel.
    (Alexandria Engineering Journal, Elsevier, 2015) M. Rehman; Aun Haider
    t The peristaltic flow and heat transfer through a symmetric channel in the presence of heat sink/source parameter have been analyzed in this paper. It also deals with the effect of the natural convection coefficient in the momentum equation. Low Reynolds number and small wave number approximation are used to convert the non-linear partial differential equations into the non-linear ordinary differential equations. In order to solve the governing model, perturbation method has been chosen by taking a (material parameter) as a small parameter. Expressions have been obtained for temperature, velocity, stream function, pressure rise and frictional forces. The features of the flow characteristics are analyzed by plotting graphs and the results are discussed in details. It has been observed that velocity increases with an increase of a (material parameter). The peristaltic pumping and in the copumping region the pumping rate decreases by increasing the value of a (material parameter). The size of the trapped bolus decreases by increasing the value of a (material parame
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    K-medoids based clustering of planetlab’s slice-centric data
    (Natural Sciences Publishing Cor., 2013) Aun Haider
    This paper investigates the application of widely used K-Medoids based clustering algorithm on data collected through CoMon facility for the PlanetLab testbed. The averaged values of various metrics in passively collected slice-centric data has been considered for clustering purposes. Various groups of slices, depicting similar resource usage patterns have been identified in original data set. These clusters have been represented in reduced dimensional space formed by first two principal components of original data set. In order to capture variations in pattern of resource usage by various slices at a PlanetLab node, clustering of standard deviations of various metrics have also been carried out. Further, combining averaged and standard deviation, clustering has also been performed on index of dispersion computed from the original data set. It has been found that K-medoid based clustering can effectively split the original data space into various sub-spaces of different resource usage behaviour of slices. Thus, it can lead to better resource management and control in publicly available testbeds.
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    A survey on waste heat recovery: electric power generation and potential prospects within Pakistan.
    (Renewable and Sustainable Energy Reviews, Elsevier, 2016) Kamran Zeb; Waqar Uddin; Aun Haider
    Waste heat recovery system plays a pivotal role for heat extractions in every energy consuming sector. ThermoElectric Module converts this waste heat into useful work done as “electric energy”. Electric energy thus produced possesses many promissory benefits, such as: (a) energy storage in DC batteries, (b) running various loads in residential, commercial and industrial sector, (c) exporting power to grid, thus earning valuable revenues, (d) maintain economic growth of plant, and (e) environment friendly system. Recently, among various renewable energy technologies, Waste Heat Recovery (WHR) is paid much consideration in commercial, residential, and industrial sectors. In past decade, a number of WHR technologies are developed and improved. In this paper, relevant research works are reviewed regarding existing technologies of WHR. Thermoelectric Generator (TEG) is one of extensively emerging WHR technique among existing technologies. TEG with promising features, such as: simpler structure, vast scalability, solid state operation, the absence of toxic residuals, a long life span of reliable operation, no noise or vibration, and lack of chemical reaction or moving parts. Basic principle of TEG with its series and parallel arrangement for voltage and current enhancement is also reviewed. Our work described a standalone thermoelectric module generate 1–125 W whose modular arrangement produces ~5 kW and the wattage improvement is defendant on array size. The potential application of TEG in various applications are comprehensively discussed and described. A detailed description to Pakistan energy status and WHR potential especially in Cement Industry is assessed in this survey. Finally, the TEGs model in Matlab/SimScape for direct heat energy harvesting with DC/DC converter is simulated, as a case study of “Officer Colony, Abbottabad, Pakistan”.