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Wireless Personal Communications - Recently, the theory of effective rate has attracted much attention, since it can take the delay aspect into account when performing channel capacity analysis. In... 相似文献
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Jain Amita Yadav Sudesh Vij Sonakshi Kumar Yogesh Tayal Devendra Kumar 《Wireless Personal Communications》2020,110(3):1303-1321
Wireless Personal Communications - Traffic network is basically a “network of networks” consisting of mainly two types of networks: road network and a travel network. Due to drastic... 相似文献
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Multimedia Tools and Applications - In the way of communication, facial expression act as non-verbal communication and play an important role in social interaction by providing some contextual... 相似文献
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The bulk copolymerization of styrene–acrylonitrile monomers using styrene‐N+–montmorillonite complex as a comonomer in the polymerization was studied. The X‐ray diffraction (XRD) analysis showed that part of the styrene‐N+–montmorillonite complex remained non‐dispersed (immiscible) and the copolymer was excluded from the interlayer of the immiscible part of the clay. The successive chemical extraction process revealed that a reasonable amount of the styrene–acrylonitrile copolymer was directly attached to the styrene‐N+–montmorillonite complex and enveloped the clay. Highly exfoliated clay lamella and nanospheres (3–5 nm) were observed by transmission electron microscopy (TEM). The montmorillonite clay assume two different morphologies, immiscible and exfoliated, on the basis of the XRD and TEM data. A simple method of calculation of the ratio of the exfoliated/immiscible amounts of the clay indicated that the amount of the styrene‐N+–montmorillonite complex exfoliated into separate lamella was 40 % (w/w) of the amount of the clay samples containing 2 % of the (styrene‐N+–montmorillonite complex) clay. This amount of exfoliated clay decreases with the increase of the concentration of the clay. The presence of the styrene‐N+–montmorillonite clay in the copolymerization reaction had a minor effect on both the copolymer composition and the molecular weight. Modification of the clay with the derivatized styrene monomer can achieve a nanocomposite using a percentage no more than 4 % (w/w) of complex in the copolymer. Copyright © 2004 Society of Chemical Industry 相似文献
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Higher order elastic constants have been calculated in ZnS at 300 K and 500 K following the interaction potential model. Ultrasonic attenuation, velocity and other related parameters have been calculated using the higher order elastic constants for the different size of the material at 500 K. The size dependency of the ultrasonic properties is discussed in correlation with elastic, thermal and electrical properties. It has been found that the thermal conductivity is the main contributor to the behaviour of the ultrasonic attenuation as a function of the size and the responsible cause of attenuation is phonon-phonon interaction. The semiconducting nature of ZnS film has been achieved with the study of size variation of thermal relaxation time and ultrasonic attenuation. 相似文献
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N. K. Acharya P. K. Yadav S. Wate Y. K. Vijay F. Singh D. Kavasthi 《Bulletin of Materials Science》2004,27(5):417-420
Ion irradiation of Si8+ ion beam of 100 MeV was scattered by a gold foil on a Mylar membrane of 25 Μm thickness in the form of film roll (width,
12.5 cm and length, 400 cm) at the Nuclear Science Centre, New Delhi. The characterization of etched nuclear tracks was carried
out by gas permeation measurements. The samples cut from the film roll of required size for permeability measurements were
etched in a controlled manner in a constant temperature bath of 6N NaOH solution. The opening of the conical etched tracks
was characterized by hydrogen gas permeation. 相似文献
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An asymmetric line-axis compound parabolic concentrating single basin solar still of concentration 1.15, exit aperture 0.24 metres and length 0.48 metres, 30° inclination and 60° half acceptance angle has been designed fabricated and tested. 相似文献
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Md. A. Mohiddon R. Kumar P. Goel K. L.Yadav 《Dielectrics and Electrical Insulation, IEEE Transactions on》2007,14(1):204-211
The aim of this study is to determine the effect of Nb5+ doping on PZT (65/35) based bulk materials in their structure, micro structure and electrical properties. The Nb content was chosen 0-9 mole%. These materials were prepared by conventional mixed oxide method. X ray diffraction studies suggest the compound to be of rhombohedral perovskite phase. Excess addition of Nb result in pyrochlore and fluorite phase develops in PZT (65/35) sample. Detailed studies of dielectric constant as a function of temperature (40degC to 500degC) and frequency (100 Hz to 1 MHz) suggest that the compounds undergo diffuse type of phase transition. Maximum dielectric constant and resistivity were found to be strongly dependent on doping and measuring frequencies. Using complex impedance analysis micro structural parameters such as bulk and grain boundary resistance, bulk charge carrier concentration and relaxation time were determined 相似文献