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101.
Lopes Elio Jordan Kataria Shaolin Keshav Shashank Ikram Sumaiya Thaseen Ghalib Muhammad Rukunuddin Shankar Achyut Krichen Moez 《Wireless Networks》2022,28(7):3111-3125
Wireless Networks - In centralized video streaming platforms, the platform owner, rather than the content producer, controls most of the content uploaded on the centralized video... 相似文献
102.
Nasedkin Andrey Nassar Mohamed Elsayed 《International Journal of Mechanics and Materials in Design》2022,18(3):611-631
International Journal of Mechanics and Materials in Design - This paper focuses on the numerical analysis of the properties of porous piezoelectric composites with metal-doped pore surfaces and... 相似文献
103.
Kouaissah Noureddine Ortobelli Lozza Sergio Jebabli Ikram 《Computational Economics》2022,60(3):833-859
Computational Economics - This paper investigates the implications for portfolio theory of using multivariate semiparametric estimators and a copula-based approach, especially when the number of... 相似文献
104.
105.
Nassar Sabry S. Faragallah Osama S. El-Bendary Mohsen A. M. 《Wireless Personal Communications》2021,119(1):37-61
Wireless Personal Communications - Due to the widely spreading of fake news utilizing image manipulation and its bad effects, this paper investigates efficient image contents verification and... 相似文献
106.
Application of plane waves for accurate measurement of microwavescattering from geophysical surfaces
Gogineni S. Jezek K.C. Peters L. Young J.D. Beaven S.G. Nassar E.M. 《Geoscience and Remote Sensing, IEEE Transactions on》1995,33(3):627-633
The authors utilized the concept of a compact antenna range to obtain plane-wave illumination to accurately measure scattering properties of simulated sea ice. They also made simultaneous measurements using conventional antennas. Measured scattering coefficients obtained with the plane-wave system at 10 GHz decreased by about 35 dB when the incidence angle increased from 0° to 10°. Scattering coefficients derived from data collected with the radar system at 13.5 GHz using conventional far-field antennas decreased by about 20 dB over the same angular region. This demonstrates that the far-field properties of a widebeam antenna are inadequate for measuring the angular scattering response of smooth surfaces. They believe that application of the compact antenna range concept for scattering measurements has a wide range of applications and is the solution to the long-standing problem of how to directly measure scattering consisting of coherent and incoherent components 相似文献
107.
In this paper, we propose the geometric-based channel modeling technique as a means to establish innovative models for the power azimuth spectrum (PAS). When the geometry of the environment is matched to that of the TSUNAMI II project, the PAS model we achieve (referred to as the secant-square model) may be compared to the Laplacian model introduced previously in the literature. In this case, we observe that our model is a better fit to the TSUNAMI II project measurements. Specifically, our model has a simple mathematical representation and demonstrates a lower squared error when compared to measurement data, and considers effects ignored in the earlier modeling (e.g., the nonzero values at the edge of the PAS). Moreover, the proposed geometric-based channel modeling technique extends to other environments with different topologies, whereas the earlier Laplacian model is limited to the TSUNAMI II measurement environment. 相似文献
108.
Two properties characterizing mixtures of exponential distributions are obtained. The first result, suggested by Puri (1973), is improving in the case of a mixture of two exponentials. A result generalizing that of Nassar & Mahmoud (1985) is considered 相似文献
109.
H. M. Asfour M. M. Nassar O. A. Fadali M. S. El-Geundi 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(1):28-35
Decolourisation of a dilute solution of a basic dyestuff was carried out by using hardwood sawdust as adsorbent. At 80°C 85% decolourisation occurred within 100 min at an initial concentration (Co) of 200 mg dm?3. There was a 44% reduction in contact time when the temperature was raised from 25 to 80°C. The rate parameter for different initial dye concentrations was found to follow the equation: kco=4.20Co0.88 and the rate parameter for different mean diameter dm followed the equation kdm=4.1 (l/dm)0.135. The activation energy of the process was 9.83 kJ mol?1 which shows that the rate controlling step is intraparticle diffusion. 相似文献
110.
Said E.H. Nassar D.E.M. Fahmy G. Ammar H.H. 《Information Forensics and Security, IEEE Transactions on》2006,1(2):178-189
Automating the process of postmortem identification of individuals using dental records is receiving increased attention. Teeth segmentation from dental radiographic films is an essential step for achieving highly automated postmortem identification. In this paper, we offer a mathematical morphology approach to the problem of teeth segmentation. We also propose a grayscale contrast stretching transformation to improve the performance of teeth segmentation. We compare and contrast our approach with other approaches proposed in the literature based on a theoretical and empirical basis. The results show that in addition to its capability of handling bitewing and periapical dental radiographic views, our approach exhibits the lowest failure rate among all approaches studied. 相似文献