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981.
982.
Kyriazakos Sofoklis Mihaylov Mihail Anggorojati Bayu Mihovska Albena Craciunescu Razvan Fratu Octavian Prasad Ramjee 《Wireless Personal Communications》2016,87(3):1093-1111
Wireless Personal Communications - Independent living of senior citizens is one of the main challenges linked to the ageing population. Senior citizens may suffer from a number of diseases,... 相似文献
983.
针对传统红外与可见光图像融合算法中存在的细节信息不够丰富, 边缘信息保留不够充分等问题, 文中提出了一种基于四阶偏微分方程(Fourth-order partial differential equation, FPDE)的改进的图像融合算法.算法首先采用FPDE将已配准的红外与可见光图像进行分解, 得到高频分量和低频分量; 然后, 对高频分量采用基于主成分分析(Principal component analysis, PCA)的融合规则来得到细节图像, 对低频分量采用基于期望值最大(Expectation maximization, EM)的融合规则来得到近似图像; 最后, 通过组合最终的高频分量和低频分量来重构得到最终的融合结果.实验是建立在标准的融合数据集上进行的, 并与传统的和最近的融合方法进行比较, 结果证明所提方法得到的融合图像比现有的融合方法能有效地综合红外与可见光图像中的重要信息, 有更好的视觉效果. 相似文献
984.
Ashish Agrawal Raj Kumar Vishwakarma Vineet R. Tripathi Anil K. Kothari Bindeshwar Prasad Jitesh Kumar 《钢铁冶炼》2013,40(4):373-382
The key to excellent casthouse operation are low cost, high productivity, dry hearth and high casting rate while minimising the consumable material. The stable blast furnace operation requires proper control of drainage rate of liquid hot metal and slag from hearth. The productivity of blast furnace can be effectively increased if drainage rate is considerably increased. If the drainage rate is controlled, the periodic tapping of hot metal and slag from hearth can be made effective. This paper highlight the improvement made in casting practice by controlling the hearth liquid level in blast furnace. The improvements have made significant change in casthouse management. It is well demonstrated that various casthouse operations have migrated from one regime of operation to another regime and various consumable items are significantly reduced. The importance of increasing the drainage rate in improving the productivity of blast furnace is explained in details. 相似文献
985.
986.
Shilpa Prasad Kodolikar Kulkarni Dhananjay S. Bhatkhande Viswas Pangarkar Prashant Kulkarni 《分离科学与技术》2018,53(1):61-70
Liquid–liquid equilibrium data for the system consisting of toluene, n-heptane and Aliquat 336 ionic liquid was obtained at 303.15 K and atmospheric pressure. The values of distribution coefficient and selectivity were evaluated. Mathematical model relating distribution coefficient and dispersion, dipolar interaction and hydrogen bonding has been developed. Hansen’s solubility parameters were used to determine the parameters. The model was applied for various ionic liquids as solvents. The model predicted the trends similar to the trend reported in the literature. Thus model can predict better solvent for the given extraction application. This methodology has great potential to act as a knowledge-based framework to aid development of new tailor-made solvents. This will save cost and time in experimentation and analysis. 相似文献
987.
Micropolar fluid theory, which is a possible non-newtonian model of a suspension of rigid particle additives, is applied to the study of the lubrication of an infinitely long and an infinitesimally short journal bearing. The variation in viscosity along the film thickness is taken into consideration. The prominent feature of the presence of solid particles in the lubricant is an increased effective viscosity which increases the load capacity and decreases the coefficient of friction. Whereas viscosity variation tends to decrease both the load and the coefficient of friction for the non-micropolar case, the combined effect is to increase the load and to decrease the coefficient of friction. 相似文献
988.
Rohit Nair Vijayaraghavan Varadharajan Sagar Joglekar Rajarathnam Nallusamy Sanjoy Paul 《Multimedia Tools and Applications》2014,73(2):763-778
Content in the digital form can be easily copied and distributed without permission of the owner. As a result, it is of paramount importance to protect content and deter illegal distribution using content protection mechanisms like embedding an imperceptible watermark into the content. Given that consumers want access to content from anywhere using any device, it is necessary to transcode content keeping in mind the limitations of the devices in terms of processing power and network connectivity. However, it is important that the watermark embedded in the content is preserved even after transcoding. The proposed approach embeds in a video, an imperceptible yet robust watermark which is resistant to transcoding. This approach focuses on the H.264 codec because of its widespread use in the industry. 相似文献
989.
P. D. Reddi N. K. Mukhopadhyay B. Majumdar A. K. Singh S. S. Meena S. M. Yusuf N. K. Prasad 《Bulletin of Materials Science》2014,37(4):815-821
Alloys of Fe-Si-B with varying compositions of Mn were prepared using high energy planetary ball mill for maximum duration of 120 h. X-ray diffraction (XRD) analysis suggests that Si gets mostly dissolved into Fe after 80 h of milling for all compositions. The residual Si was found to form an intermetallic Fe3Si. The dissolution was further confirmed from the field emission scanning electron microscopy/energy dispersive X-ray analysis (FE-SEM/EDX). With increased milling time, the lattice parameter and lattice strain are found to increase. However, the crystallite size decreases from micrometer (75–95 μm) to nanometer (10–20 nm). Mössbauer spectra analysis suggests the presence of essentially ferromagnetic phases with small percentage of super paramagnetic phase in the system. The saturation magnetization (M s), remanance (M r) and coercivity (H c) values for Fe-0Mn sample after 120 h of milling were 96.4 Am2/kg, 11.5 Am2/kg and 12.42 k Am?1, respectively. However, for Fe-10Mn-5Cu sample the M s, H c and M r values were found to be 101.9 Am2/kg, 10.98 kA/m and 12.4 Am2/kg, respectively. The higher value of magnetization could be attributed to the favourable coupling between Mn and Cu. 相似文献
990.
R. V. S. Prasad M. Srinivas M. Manivel Raja G. Phanikumar 《Metallurgical and Materials Transactions A》2014,45(4):2161-2170
The microstructure and magnetic properties of Ni2MnGa base alloys with “Fe” substitution in place of “Mn” are studied. The processing technique used is melt spinning at wheel speeds of 20 m/s and 30 m/s followed by annealing at 1273 K (1000 °C) for 1 hour. Fe content is varied from 2 at. pct to 11 at. pct for alloys of Ni50Mn(25?x)Fe x Ga25 with Heusler stoichiometry. Austenite with B2 partial atomic ordering and premartensitic tweed structures were found at room temperature for all the alloys at different wheel speeds. After annealing at 1273 K (1000 °C) for 1 hour, austenite phase with L21 Heusler atomic ordering is stabilized in samples of all the processing conditions. Saturation magnetization, martensitic transformation temperature, and Curie temperature are measured. Martensite temperature and Curie temperature increase in proportion to iron content in the alloy. Saturation magnetization is sensitive to the phase content and compositional inhomogeneities. 相似文献