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排序方式: 共有921条查询结果,搜索用时 31 毫秒
1.
Singh Nalin Rathore Santosh Singh Kumar Sandeep 《Multimedia Tools and Applications》2022,81(27):38887-38919
Multimedia Tools and Applications - The video surveillance activity generates a vast amount of data, which can be processed to detect miscreants. The task of identifying and recognizing an object... 相似文献
2.
Wireless Personal Communications - In recent years, the emergence of Internet of things and cyber-physical system provide a proactive and efficacious solution to enable remote monitoring, machine... 相似文献
3.
Geraint Johnes Swati Virmani 《International Transactions in Operational Research》2020,27(4):1869-1885
Data from the Young Lives study are used to evaluate the efficiency of education systems in four low and middle income countries: Ethiopia, India, Peru and Vietnam. A meta‐frontier variant of data envelopment analysis is used to assess the relative performance of each country's system, and, within each country, to evaluate the impact of public and private schooling, and of urban and rural location. Comparisons are drawn between the four countries; the results indicate that in no country does the educational system perform uniformly badly or well. Conditioning on the inputs available, rural areas are often indicative of higher levels of efficiency, thus suggesting a number of implications for policy. 相似文献
4.
Manoj Karakoti Ritu Jangra Sandeep Pandey Pawan Singh Dhapola Sunil Dhali Suman Mahendia Pramod K Singh Nanda Gopal Sahoo 《International Journal of Applied Ceramic Technology》2020,17(4):1899-1908
This study deals with the utility of mini spray dryer process to improve the dispersibility, of graphene oxide(GO) and its application for high-performance supercapacitor. Initially, the neutral solution of GO was obtained using the modified Hummer's method. After this, the prepared GO solution was processed by mini spray dryer to obtain a more purified, lighter, and dispersed form of GO which is named as spray dryer processed GO (SPGO). The SPGO thus obtained showed excellent dispersibility behavior with various solvents, which is not found in case of conventional oven drying. Furthermore, utility of SPGO and its reduced form (r-SPGO) for supercapacitor applications have been investigated. Results obtained from the cyclic voltammetry(CV) analysis, impedance, and charge-discharge behavior of supercapacitor fabricated using r-SPGO shows enhanced features. Therefore, the simple spray dried GO and its reduced form, that is, r-SPGO can be utilized as a potential candidate for the supercapacitor application. Herein, as synthesized SPGO exhibited the specific capacitance of 12.07 and 37.6 F/g with PVA-H3PO4 and 1 mol/L H3PO4, respectively, at a scan rate of 5 mV/s. On the other hand, reduced form of SPGO, that is, r-SPGO showed the specific capacitance of 27.16 and 230 F/g with PVA-H3PO4 and 1 mol/L H3PO4, respectively. 相似文献
5.
Poly(ethylene aspartate) [PEA] was synthesized by the melt condensation of D,L-aspartic acid and ethylene glycol. PEA containing pendent amino and carbonyl groups in its repeating chain was used as the polymeric ligand for complexation with transition metal ions, viz. Co(II), Ni(II), Cu(II), Mn(II), Zn(II), Cd(II), Ca(II), Mg(II), Pb(II) and Hg(II). Complexation was found to be most effective in DMSO. The resulting polyester-metal complexes were solid coloured materials which have been characterized by IR spectroscopy, elemental analysis and magnetic susceptibility measurements. The thermal stability of the polyester-metal complexes was investigated by thermogravimetric analysis (TGA). On the basis of the physico-chemical studies, an oxygen and nitrogen coordinated structure for the polyester-metal complexes is proposed. 相似文献
6.
Due to technology scaling and increasing clock frequency, problems due to noise effects lead to an increase in design/debugging efforts and a decrease in circuit performance. This paper addresses the problem of efficiently and accurately generating two-vector tests for crosstalk induced effects, such as pulses, signal speedup and slowdown, in digital combinational circuits. These noise effects can propagate through a circuit and create a logic error in a latch or at a primary output. We have developed a mixed-signal test generator, called XGEN, that incorporates classical static values as well as dynamic signals such as transitions and pulses, and timing information such as signal arrival times, rise/fall times, and gate delay. In this paper we first discuss the general framework of the test generation algorithm followed by computational results. Comparison of results with SPICE simulations confirms the accuracy of this approach. 相似文献
7.
Glass fiber-reinforced epoxy composites were prepared from the matrix resins tetraglycidyl diaminodiphenylmethane 1 Systematic name: N,N,N′,N′-Tetrakis(2,3-epoxypropyl)-4,4′-diaminodiphenylmethane. (TGDDM) and tetraglycidyl bis(o-toluidino)-methane 2 Systematic name: N,N,N′,N′-Tetrakis(2,3-epoxypropyl)-4,4′-bis(o-toluidino)methane. (TGMBT) using various amines like 4,4′-diaminodiphenylmethane (DDM), 4,4′-diaminodiphenylsulfone (DDS) and diethylene triamine (DETA) as curing agents. The fabricated laminates were evaluated for their mechanical and dielectrical properties and chemical resistance. The composites prepared using an epoxy fortifier (20 phr) showed significant improvement in the mechanical properties. 相似文献
8.
Bret J. Chisholm William D. Richards Timothy E. Banach Sofia Soloveichik James F. Kelley Greg R. Bradtke Sandeep Dhawan 《应用聚合物科学杂志》2006,100(6):4762-4771
Structure–property relationships have been developed for sulfonated poly(butylene terephthalate) copolymers. The compositional variables investigated were sulfonate content, molecular weight, and polymer endgroup composition, and the fundamental polymer properties evaluated were melt viscosity, crystallization kinetics, and impact strength. It was found that all compositional variables significantly affect all of the polymer properties of interest. The most interesting effect is the influence of polymer endgroup composition on polymer properties. The trends indicate that the carboxylic acid endgroups form intermolecular interactions with sodium sulfonate groups, resulting in a decrease in the strength of intermolecular ionic interactions between sodium sulfonate groups. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4662–4771, 2006 相似文献
9.
Shamsher S. Kanwar Ghansham S. Chauhan Swapandeep S. Chimni Sandeep Chauhan Gajendra S. Rawat Rajeev K. Kaushal 《应用聚合物科学杂志》2006,100(2):1420-1426
An alkaline thermotolerant bacterial lipase of Bacillus coagulans MTCC‐6375 was purified and immobilized on a methacrylic acid and dodecyl methacrylate (MAc‐DMA) hydrogel. The lipase was optimally bound to the matrix after 20 min of incubation at 55°C and pH 9 under shaking conditions. The matrix‐bound lipase retained approximately 50% of its initial activity at 70–80°C after 3 h of incubation. The immobilized lipase was highly active on medium chain length p‐nitrophenyl acyl ester (C: 8, p‐nitrophenyl caprylate) than other p‐nitrophenyl acyl esters. The presence of Fe3+, NH4+, K+, and Zn2+ ions at 1 mM concentration in the reaction mixture resulted in a profound increase in the activity of immobilized lipase. Most of the detergents partially reduced the activity of the immobilized lipase. The immobilized lipase performed ~62% conversion in 12 h at temperature 55°C. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1420–1426, 2006 相似文献
10.
Given a set of points \(P \subset\mathbb{R}^{d}\) , the k-means clustering problem is to find a set of k centers \(C = \{ c_{1},\ldots,c_{k}\}, c_{i} \in\mathbb{R}^{d}\) , such that the objective function ∑ x∈P e(x,C)2, where e(x,C) denotes the Euclidean distance between x and the closest center in C, is minimized. This is one of the most prominent objective functions that has been studied with respect to clustering. D 2-sampling (Arthur and Vassilvitskii, Proceedings of the Eighteenth Annual ACM-SIAM Symposium on Discrete Algorithms, SODA’07, pp. 1027–1035, SIAM, Philadelphia, 2007) is a simple non-uniform sampling technique for choosing points from a set of points. It works as follows: given a set of points \(P \subset\mathbb{R}^{d}\) , the first point is chosen uniformly at random from P. Subsequently, a point from P is chosen as the next sample with probability proportional to the square of the distance of this point to the nearest previously sampled point. D 2-sampling has been shown to have nice properties with respect to the k-means clustering problem. Arthur and Vassilvitskii (Proceedings of the Eighteenth Annual ACM-SIAM Symposium on Discrete Algorithms, SODA’07, pp. 1027–1035, SIAM, Philadelphia, 2007) show that k points chosen as centers from P using D 2-sampling give an O(logk) approximation in expectation. Ailon et al. (NIPS, pp. 10–18, 2009) and Aggarwal et al. (Approximation, Randomization, and Combinatorial Optimization. Algorithms and Techniques, pp. 15–28, Springer, Berlin, 2009) extended results of Arthur and Vassilvitskii (Proceedings of the Eighteenth Annual ACM-SIAM Symposium on Discrete Algorithms, SODA’07, pp. 1027–1035, SIAM, Philadelphia, 2007) to show that O(k) points chosen as centers using D 2-sampling give an O(1) approximation to the k-means objective function with high probability. In this paper, we further demonstrate the power of D 2-sampling by giving a simple randomized (1+?)-approximation algorithm that uses the D 2-sampling in its core. 相似文献