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排序方式: 共有1285条查询结果,搜索用时 265 毫秒
1.
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
4.
D. Yadav 《Materials Science & Technology》2015,31(4):494-500
Copper particles were incorporated and retained in elemental state in an aluminium matrix by friction stir processing thereby producing a non-equilibrium particulate composite. The processed Al–Cup composite exhibited improved strength with significantly high ductility. The composite was stable up to a temperature of more than 300°C. Thermal exposure at 350°C for more than 10 min led to diffusion of Cu atoms into the Al matrix forming a core-shell type structure in the Cu particles and thus producing an Al–Cu core-shell composite. The shell consists of multiple layers, the thickness of which was controllable. 相似文献
5.
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
6.
Structures of grain boundaries and triple line junctions in nanocrystalline materials are of interest owing to large fractions
of atoms in nanocrystalline materials being at these interfacial positions. Grain boundary and triple line junction structures
in nanocrystalline palladium have been studied using high-resolution transmission electron microscopy (HRTEM). The main micro
structural features observed include the varying atomic structures of grain boundaries and the presence of disordered regions
at triple line junctions. Also, there is variation in lattice parameters in different nanocrystalline grains. Geometric phase
analysis is used to quantify atomic displacements within nanocrystalline grains. Displacement fields thus detected indicate
links to the interface structures. 相似文献
7.
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
8.
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
9.
The thermal expansion of a titanium modified, swelling resistant austenitic stainless steel designated as D9 is studied by measuring the lattice parameter as a function of temperature in the range 300-1300 K by high-temperature X-ray diffraction technique. The thermal expansion data thus obtained is in reasonable agreement with the typical thermal expansion values reported for similar nuclear grade austenitic stainless steels. However, at temperatures exceeding 900 K, the measured thermal expansivity exhibits a pronounced non-linear increase due partly to the precipitation of complex carbide and intermetallic phases. The high-temperature thermal expansion data obtained in the present study are augmented by modelling the low-temperature thermal expansion behaviour by Grüneisen formalism. 相似文献
10.
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