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1.
Naveed Aslam Mirza Hikmat Ullah Khan Khalid Iqbal Saqib Iqbal Muhammad Imran 《New Review of Hypermedia and Multimedia》2013,19(4):335-345
ABSTRACTThe quality of user-generated content over World Wide Web media is a matter of serious concern for both creators and users. To measure the quality of content, webometric techniques are commonly used. In recent times, bibliometric techniques have been introduced to good effect for evaluation of the quality of user-generated content, which were originally used for scholarly data. However, the application of bibliometric techniques to evaluate the quality of YouTube content is limited to h-index and g-index considering only views. This paper advocates for and demonstrates the adaptation of existing Bibliometric indices including h-index, g-index and M-index exploiting both views and comments and proposes three indices hvc, gvc and mvc for YouTube video channel ranking. The empirical results prove that the proposed indices using views along with the comments outperform the existing approaches on a real-world dataset of YouTube. 相似文献
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Horseshoe vortex topological structure has been studied extensively in the past, traditional “saddle of separation” and new “attachment saddle point” topologies found in literature both have theoretical basis and experimental and computational evidences for support. The laminar incompressible juncture flows at low Reynolds numbers especially are observed to have new topology. Studies concerning the existence of the new topology though found in literature, the topological evolution and its dependency on various critical flow parameters require further investigation. A Particle Image Velocimetry based analysis is carried out to observe the effect of aspect ratio, δ*/D and shape of the obstacle on laminar horseshoe vortex topology for small obstacles. Rise in aspect ratio evolves the topology from the traditional to new for all the cases observed. The circular cross section obstacles are found more apt to having the new topology compared to square cross sections. It is noted that the sweeping effect of the fluid above the vortex system in which horseshoe vortex is immersed plays a critical role in this evolution. Topological evolution is observed not only in the most upstream singular point region of horseshoe vortex system but also in the corner region. The corner vortex topology evolves from the traditional type to new one before the topological evolution of the most upstream singular point, resulting in a new topological pattern of the laminar juncture flows “separation-attachment combination”. The study may help extend the understanding of the three-dimensional boundary layer separation phenomenon. 相似文献
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Asma Ayaz Wajid Zaman Fazal Ullah Saddam Saqib Shayan Jamshed Saraj Bahadur Abdul Shakoor Bushra Arshad 《Microscopy research and technique》2020,83(1):81-87
In all over the world, herbal drugs are usually adulterated with similar species or varieties due to incorrect identification. Most of herbal products devoid purity and quality, therefore an attempt was carried out to identify plant species and authenticate its herbal drug products from Mentha suaveolens. Microscopy tools provide an excellent platform to identify plants at species level. In this study, microscopic and pharmacokinetic parameters of M. suaveolens were observed. Plant species were collected from high diverse areas of Northern Pakistan. Macro and micro‐morphology including palynology and anatomical features were analyzed to study M. suaveolens. Species characteristics were studied, while implementing microscopic techniques for the delimitation and identification of the species. Traditionally Mentha species are used to cure several diseases that is, digestive disorders, respiratory disorders. Micromorphology (stem, leaves, flowers structure, length etc.), palynology (shape, size of pollen etc.), and anatomical characters (types of stomata, epidermal cell shape, and trichomes) were studied. Micromorphology and anatomical characters were of great interest and significance to discuss the taxonomy of the species. Taxonomic characters were studied to characterize and authenticate the species. The aim of the present study is to observe in detail the taxonomic identification of the species in term of morphology, palynology, and foliar epidermal anatomy for the correct identification along with their medicinal uses in the area. 相似文献
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Saqib Murtaza Farhad Ali Aamina Nadeem Ahmad Sheikh Ilyas Khan Kottakkaran Sooppy Nisar 《计算机、材料和连续体(英文)》2020,65(3):2033-2047
It is a very difficult task for the researchers to find the exact solutions to
mathematical problems that contain non-linear terms in the equation. Therefore, this article
aims to investigate the viscous dissipation (VD) effect on the fractional model of Jeffrey
fluid over a heated vertical flat plate that suddenly moves in its own plane. Based on the
Atangana-Baleanu operator, the fractional model is developed from the fractional
constitutive equations. VD is responsible for the non-linear behavior in the problem. Upon
taking the Laplace and Fourier sine transforms, exact expressions have been obtained for
momentum and energy equations. The influence of relative parameters on fluid flow and
temperature distribution is shown graphically. As special cases, and for the sake of
correctness, the corresponding results for second-grade fluid and Newtonian viscous fluid
are also obtained. It is interesting to note that fractional parameter α provides more than
one line as compared to the classical model. This effect represents the memory effect in the
fluid which is not possible to elaborate by the classical model. It is also worth noting that
the temperature profile of the generalized Jeffrey fluid rises for higher values of Eckert
number which is due to the enthalpy difference of the boundary layer. 相似文献
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M. Saqib I. Weiss G. M. Mehrotra E. Clevenger A. G. Jackson H. A. Lipsitt 《Metallurgical and Materials Transactions A》1991,22(8):1722-1728
Ti-43Al (atomic percent) alloy containing a dispersion of 7 vol pct TiB2 particles was exposed to various thermal treatments to determine the stability of TiB2 in an ⇌2 + β-phase matrix. No new phases were detected at the particle/matrix interfaces even after thermal exposure at 1473 K for
7 days. The absence of an Al peak in the energy dispersive X-ray analysis system (EDS) spectra from TiB2 particles chemically extracted from the specimens aged at 1473 K for 7 days indicated no diffusion of Al from the matrix
to the particles. These results indicate that TiB2 is stable in an α2+ β matrix at 1473 K.
E. Clevenger, formerly Undergraduate Student, Department of Mechanical and Materials Engineering, Wright State University 相似文献
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Flexible Transparent Reduced Graphene Oxide Sensor Coupled with Organic Dye Molecules for Rapid Dual‐Mode Ammonia Gas Detection 下载免费PDF全文
Le Thai Duy Tran Quang Trung Vinh Quang Dang Byeong‐Ung Hwang Saqib Siddiqui Il‐Yung Son Seung Kyun Yoon Dong June Chung Nae‐Eung Lee 《Advanced functional materials》2016,26(24):4329-4338
Flexible chemical sensors utilizing chemically sensitive nanomaterials are of great interest for wearable sensing applications. However, obtaining high performance flexible chemical sensors with high sensitivity, fast response, transparency, stability, and workability at ambient conditions is still challenging. Herein, a newly designed flexible and transparent chemical sensor of reduced graphene oxide (R‐GO) coupled with organic dye molecules (bromophenol blue) is introduced. This device has promising properties such as high mechanical flexibility (>5000 bending cycles with a bending radius of 0.95 cm) and optical transparency (>60% in the visible region). Furthermore, stacking the water‐trapping dye layer on R‐GO enables a higher response as well as workability in a large relative humidity range (up to 80%), and dual‐mode detection capabilities of colorimetric and electrical sensing for NH3 gas (5–40 ppm). These advantageous attributes of the flexible and transparent R‐GO sensor coupled with organic dye molecules provide great potential for real‐time monitoring of toxic gas/vapor in future practical chemical sensing at room conditions in wearable electronics. 相似文献