Publications by authors named "Usman Shahzad"

In traditional statistics, all research endeavors revolve around utilizing precise, crisp data for the predictive estimation of population mean in survey sampling, when the supplementary information is accessible. However, these types of estimates often suffer from bias. The major aim is to uncover the most accurate estimates for the unknown value of the population mean while minimizing the mean square error (MSE).

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Extreme winds are becoming more common among environmental events with the most catastrophic societal consequences. A regional frequency analysis of Daily Annual Maximum Wind Speed (DAMWS) is necessary not only for a comprehensive understanding of wind hazards but also for infrastructure design and safety, wind energy potential, disaster risk reduction, insurance and risk assessment in a particular region of study. This study investigated regional frequency analysis of DAMWS of Baluchistan and Sindh provinces of Pakistan.

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Ranked set sampling (RSS) has created a broad interest among researchers and it is still a unique research topic. It has at long last begun to find its way into practical applications beyond its initial horticultural based birth in the fundamental paper by McIntyre in the nineteenth century. One of the extensions of RSS is median ranked set sampling (MRSS).

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Commercially pure titanium (Ti) is widely used in bio-implants due to its high corrosion resistance. However, Ti exhibits marginally low mechanical and tribological properties, which limit its applications in some orthopedic implants. In this work, the Ti samples were subjected to ultrasonic surface mechanical attrition treatment (SMAT) for various durations to improve their surface properties such as hardness, strength and surface energy.

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To assess causal association of depression with subclinical coronary atherosclerosis, we performed computer-based and manual search of literature for studies which had assessed relationship of depression disorder with coronary atherosclerosis. All studies had diagnosed depression with validated tools in patients without diagnosed coronary artery disease. The Bradford Hill criteria of cause-effect association was consistently fulfilled by those studies which achieved statistical significance and further showed incremental strength of association with one or more of the following attributes: (1) prospective cohort study, met cause-effect criteria of "temporality"; (2) relatively severe and/or longer period of depression, met cause-effect criteria of "dose-response"; (3) depression with predominantly somatic symptoms cluster, met cause-effect criteria of "scientific plausibility"; (4) multiethnic larger sample, met cause-effect criteria of "population equivalence"; and (5) multicenter study, met criteria of "environmental equivalence.

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