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81.
Wireless Personal Communications - Distributed denial of service (DDoS) attacks disrupt the availability of cloud services. The detection of these attacks is a major challenge in the cloud... 相似文献
82.
Hussain Naziya Maheshwary Priti Shukla Piyush Kumar Singh Anoop 《Wireless Personal Communications》2022,126(4):2841-2868
Wireless Personal Communications - A Greedy Perimeter Coordinator Routing and Mobility Awareness (GPCR-MA) vehicular routing is a widely accepted routing protocol for VANET (Vehicular Ad hoc... 相似文献
83.
Srivastava Vishal Singh Shashank Sheshar Biswas Bhaskar 《Wireless Personal Communications》2022,126(4):3119-3146
Wireless Personal Communications - This paper proposes an combined method for manifold preservation and Subspace Eigenvectors(SE) based regression in high dimensional (HD) images. We studied... 相似文献
84.
Prateeksha Prateeksha Vivek Sharma Nemkumar Nagpoore Vishwjeet Jadaun Chandana Rao Brahma Singh 《Advanced functional materials》2023,33(28):2214852
Microbial biofilm formation on implantable devices causes chronic infections that cannot be treated with existing antimicrobials. Quorum sensing inhibitors (QSIs) have recently emerged as novel antimicrobials for the prevention of biofilm formation. But blocking QS alone is insufficient to inhibit biofilm-associated chronic infections. Herein, chitosan hollow nanospheres are capped by bacteria-responsive β-casein to form a synergistic antifouling nanosystem consisting of a QSI and bactericide. β-casein is degraded by protease in a bacteria-colonized microenvironment in situ thus, QSI and bactericide are released sequentially. The release of QSI sensitises bacteria effectively through reduction of surface hydrophobicity, eDNA content, and lipopolysaccharide production in biofilms, amplifying the chemotherapeutic action of the bactericide. Compared to the uncoated surface, the coated surface inhibits biofilm formation and removes preformed biofilms of Pseudomonas aeruginosa PAO1 and methicillin-resistant Staphylococcus aureus by 1.8 logs and 1.9 logs of biomass inhibition, respectively. The coated catheters are found to stay clean for 30 days under artificial urine flow, while the uncoated catheters are clogged by bacterial biofilms within 5 days. Finally, the long term antifouling activity in vivo is confirmed. Overall, the nanosystem is devoted to making urinary catheters resistant to bacterial biofilm formation for the long term. 相似文献
85.
The present study aims at studying ageing characteristics of conventional bitumen, polymer modified bitumen (PMB) and warm mix asphalt (WMA) by using FTIR. Results of obtained FTIR spectrum were quantified by calculating different indices and finally based on these indices ageing index of the binders for short- and long-term ageing were calculated. Results showed ageing increased amount of complex and high molecular weight components of the binders. PMB was found to have greater ageing resistance than conventional asphalt binders. In case of WMA, results found to be inconclusive, requiring further investigation. 相似文献
86.
In life testing, the failure-time distributions are often specified by choosing an appropriate hazard-rate function. The class of life-time distribution characterized by a linear hazard-rate includes the one-parameter exponential and Rayleigh distributions. Usually the parameters of the linear hazard-rate model are estimated by the method of least squares. This work is concerned with Bayes estimation of the two-parameters from a type-2 censored sample. Monte Carlo simulation is used to compare the Bayes risk of the regression estimator with the minimum Bayes risk. Discrete mixtures of decreasing failure rate distributions are known to have decreasing failure rates. The authors prove that the result holds for continuous mixtures as well 相似文献
87.
A small-signal numerical analysis of pseudomorphic GaAs- and InP-based Fabry-Perot quantum-well lasers using calculated optical gain spectra with strain effects included is reported. Examination of the effect of lifetime broadening shows that the resonance frequency increases at a rate of ~250-MHz/meV reduction in the lifetime broadening for a GaAs-based strained layer laser. The modulation speed is limited by either device heating or facet damage. If the limitation is imposed by the optical power then the modulation speed increases as the laser cavity becomes shorter and the number of quantum wells increases. If the limitation is imposed by the injection current density, however, then the modulation speed decreases for the laser with shorter cavity length. The highest modulation speed is given by an optimum well number. A resonance frequency of ~16 GHz is predicted for a pseudomorphic GaAs-based laser with 30% excess In and average output power of ~5 mW 相似文献
88.
A shrunken estimator of the Weibull shape parameter for failure censored samples is suggested. This shrunken estimator is compared with shrunken estimators previously given. Even for sample sizes of five and ten this shrunken estimator, based on failure data censored at only three and four, respectively, can be used with advantage when one has a reasonable guess for the shape parameter. This estimator has higher efficiency and nearness than other estimators 相似文献
89.
This paper deals with the problem of average life estimation when the life times follow negative exponential distribution. A minimum mean square error estimator belonging to the class of linear combination of complete sufficient statistics has been obtained. The estimator thus obtained requires knowledge of coefficient of variation. The effect of using a guessed value of coefficient of variation on the estimator has also been studied. 相似文献
90.
This paper describes an algorithm for finding the minimal cutsets between a specified source and terminal nodes of directed/undirected networks. Adjacent nodes of a source node/merged node are determined by the collection of node numbers of columns corresponding to non-zero elements of the first row of the adjacency matrix to form the reduced adjacency matrix (RAM) corresponding to merged nodes. Connectivity of RAM has been checked to obtain the minimal cutsets. 相似文献