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21.
Ranking scientific authors is an important but challenging task, mostly due to the dynamic nature of the evolving scientific publications. The basic indicators of an author’s productivity and impact are still the number of publications and the citation count (leading to the popular metrics such as h-index, g-index etc.). H-index and its popular variants are mostly effective in ranking highly-cited authors, thus fail to resolve ties while ranking medium-cited and low-cited authors who are majority in number. Therefore, these metrics are inefficient to predict the ability of promising young researchers at the beginning of their career. In this paper, we propose \(C^3\)-index that combines the effect of citations and collaborations of an author in a systematic way using a weighted multi-layered network to rank authors. We conduct our experiments on a massive publication dataset of Computer Science and show that—(1) \(C^3\)-index is consistent over time, which is one of the fundamental characteristics of a ranking metric, (2) \(C^3\)-index is as efficient as h-index and its variants to rank highly-cited authors, (3) \(C^3\)-index can act as a conflict resolution metric to break ties in the ranking of medium-cited and low-cited authors, (4) \(C^3\)-index can also be used to predict future achievers at the early stage of their career.  相似文献   
22.
Nonlinear dynamics of a third-order zero crossing digital phase locked loop (ZCDPLL) has been investigated. It has been observed that, while first and second-order ZCDPLLs show period doubling route to chaos, a third-order ZCDPLL manifests a disjoint periodic attractor in its route to chaos. Also, the complexity and predictability of the system dynamics have been characterized by using nonlinear dynamical measures such as Lyapunov exponent, Kaplan–York dimension, correlation dimension and Kolmogorov entropy. All the results show that the chaos in a third-order ZCDPLL is low dimensional.  相似文献   
23.
Photon harvesting by reducing reflection loss is the basis of photovoltaic devices. Here, we show the efficacy of Al-doped ZnO (AZO) overlayer on ion beam-synthesized nanofaceted silicon for suppressing reflection loss. In particular, we demonstrate thickness-dependent tunable antireflection (AR) from conformally grown AZO layer, showing a systematic shift in the reflection minima from ultraviolet to visible to near-infrared ranges with increasing thickness. Tunable AR property is understood in light of depth-dependent refractive index of nanofaceted silicon and AZO overlayer. This improved AR property significantly increases the fill factor of such textured heterostructures, which reaches its maximum for 60-nm AZO compared to the ones based on planar silicon. This thickness matches with the one that shows the maximum reduction in surface reflectance.

PACS

81.07.-b; 42.79.Wc; 81.16.Rf; 81.15.Cd  相似文献   
24.
In the present study, hydroxyapatite (HAp) is synthesized from different biosources like eggshell, fish scale and bovine bone in a cost effective and ecofriendly way. HAp materials were synthesized from eggshell by wet precipitation method whereas thermal decomposition method was applied in case of fish scale and bovine bone. The phase purity and crystallinity of different calcined HAp powder were determined by XRD and FTIR analyses. The thermogravimetric analysis was carried out to show thermal stability of HAp powder. Average grain sizes of sintered samples were in submicron range. The morphology of the powders were observed under scanning electron microscopy (SEM). The dried powders were wet ball milled for several hours and surfactants like Triton-X small fillers (2 / 4 mm long rod-shaped) were made for in vitro testing. In order to verify the biocompatibility of HAp powders, cytotoxicity evaluation was carried out in RAW macrophage like cell line media for an incubation period of 72 h. The cell attachment studies on HAp compacts show an excellent affinity between cells and compact surface. These results proved high biocompatibility of HAp powders obtained from different biosources for tissue engineering applications.  相似文献   
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In the course of searching environmental friendly lead-free relaxor ferroelectrics a complete phase diagram of barium zirconate titanate, Ba(Zr x Ti1− x )O3 system with compositions 0.00≤ x ≤1.00 has been developed based on their dielectric behavior. It has been shown that BaZr x Ti1− x O3 system depending on the composition, successively depicts the properties extending from simple dielectric (pure BaZrO3) to polar cluster dielectric, relaxor ferroelectric, second order like diffuse phase transition, ferroelectric with pinched phase transitions and then to a proper ferroelectric (pure BaTiO3). A comprehensive structure–property correlation of BaZr x Ti1− x O3 ceramics has been studied to understand the various ferroelectric phenomena in the whole phase diagram.  相似文献   
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A dynamic gain modification algorithm of a class of digital phase locked loops (DPLLs) has been proposed. It has been shown analytically that the modified DPLL based on the proposed algorithm can be designed to have a faster transient response besides having steady-state response and frequency acquisition range same as that of a conventional DPLL. Numerical simulation results have been given to support the analytical predictions.  相似文献   
30.
Hot metal transfer ladles were historically lined with high alumina refractories because of compatibility of high alumina refractories with the highly acidic slag, which is transferred .from the iron making plant along with hot metal. With the introduction of higher capacity ladles, technological advancement in the process and increased productivity, calls for a higher campaign life of hot metal ladles, which could not be performed by ordinary high alumina refractories. Resin bonded Al2O3- SiC-C (hereinafter ASC ) bricks gradually developed which at present taking place replacing the conventional refractories. Considerable work has been carried out in developing the ASC refractory to reach the present state. However, for higher capacity ladles still there is a lot of scope for improvement. The present paper deals with the newly developed ASC bricks, which was used in 165 ton capacity hot metal ladles in one European plant and has given a substantial increase in performance. But, the customer was not fuUy satisfied since the brick was reported to produce smokes during preheating of the ladle. In the subsequent supply the smoke generation problem was taken care by adjusting the binders and additives and eco-friendly bricks were re-engineered and supplied to the same plant, which also performed splendidly and created all time record in their plant history.  相似文献   
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