Joint load balanced stable routing and communication segment assignment in mobile cognitive radio ad‐hoc networks

The fundamental issues in mobile cognitive radio ad‐hoc networks are the selection of the optimal stable paths between nodes and proper assignment of the frequency channels/time slots (communication segments) to the links. In this paper, a joint load balanced stable routing and communication segment assignment algorithm is proposed that considers jointly the mobility prediction, mitigating the co‐channel interference and energy consumption. The novelty of the proposed algorithm lies in the increasing of the path stability, which benefits from the maximum link lifetime parameter and introduced weighting function to keep routes away from the PU's region. This avoids the negative impacts on the PUs' operations and decreases the conflict of the cognitive nodes. In the proposed algorithm, the concept of load balancing is considered that yields in the balancing energy consumption in the network, improving the network performance and distributing traffic loads on all available channels. The effectiveness of the proposed algorithm is verified by evaluating the aggregate interference energy, average end‐to‐end delay, goodput, and the energy usage per packet under 6 scenarios. The results show that the performance of the proposed algorithm is significantly better than the recently proposed joint stable routing and channel assignment protocol.     

Effect of ARB Cycle Number and Second Phase Content on Mechanical properties and Microstructure of Pb–Ag Composite

A solid state method has been found for manufacturing of lead–silver composites for use as anodes in electrowinning production. Mechanical properties and microstructure of composite were characterized via peeling, tensile and microhardness tests, and scanning electron microscopy, transmission electron microscopy and fractography. Based on the peeling test results, maximum bond strength was achieved in the presence of 0.125 wt% of Ag (1.8 N/mm). Best mechanical properties were achieved in the Pb–0.5 wt% Ag composite after 10 ARB cycles by the enhanced tensile strength rising up to 50%, yield strength up to 170%, shear strength up to 63% and hardness up to 2.6 times higher, and the strain decreasing to 68% lower. These advanced properties led to higher stiffness and considerable enhancements in dimensional stability of the anodes and they improved creep characteristics. The advanced properties of the processed Pb–Ag composite anodes could be introduced as certification for slower anode failure, upkeep, surcharge and capital expenditure of industries with essential lead anode requirement.     

Reduction of Carbon Dioxide to Carbon Nanostructures in Molten Salt: The Effect of Electrolyte Composition

JOM - The effect of the composition of the molten salt electrolyte on the morphology of carbon produced via reduction of carbon dioxide has been studied. Three different molten salt compositions...     

A novel framework for spatiotemporal monitoring and post-signal diagnosis of processes with image data

Advances in digital equipment and organizations' interest in having comprehensive and real-time information about products have increased the use of machine vision systems in organizations. In this paper, to monitor a sensory quality characteristic of a product based on images, the residual matrix of the intensity values of the nominal and captured images is divided into specific regions; then, the equality of the means of the regions is tested based on one-way ANOVA. To do so, a P-value–based control chart is applied to detect the out-of-control state as soon as possible. If an out-of-control alarm is received, Dunnett's test is used to identify region(s) with significant differences in the means of residuals (defective location[s] in the image) compared with other regions. After the locations of defective regions are identified, the change point of the process is estimated by using the maximum likelihood estimation approach. The performance of the proposed procedure is compared with some of the previous approaches in the literature. Then, the proposed procedure is implemented in a real-world case. The simulation study demonstrates the merits of the proposed procedure: It is not limited to specific geometric types of faults; it has the ability to detect multiple faults in the image; it takes less computational time; and it performs well in estimating the real time of change, as well as the location(s) and dimension(s) of the fault(s).     

Ce promoting effect on the activity and coke formation of Ni catalysts supported on mesoporous nanocrystalline γ-Al2O3 in autothermal reforming of methane

In this study methane autothermal reforming (ATR) was investigated over Ni/Al₂O₃ and Ni/Al₂O₃–CeO₂ catalysts. The catalyst carriers were prepared through a facile one-step method, which produced mesoporous nanocrystalline carriers for Ni catalysts. The samples were characterized by XRD, TPR, BET, TPO and SEM characterization techniques and the catalytic activity and stability were also studied at different conditions (GHSV and feed ratio) in methane ATR. It was found that the nickel catalyst supported on 3 wt.% Ce–Al₂O₃ exhibited higher activity compared to the catalysts supported on the Al₂O₃ and promoted Al₂O₃ with 1 and 6 wt.% Ce. The results also showed that the nickel catalyst supported on 3 wt.% Ce–Al₂O₃ possessed the highest resistance against carbon deposition in ATR reaction.     

Business intelligence using machine learning algorithms

Multimedia Tools and Applications - Business intelligence, as one of the branches of information technology, is increasingly considered by managers in today’s business world. In order to make...     

An objective method to evaluate exemplar‐based inpainted images quality using Jaccard index

Multimedia Tools and Applications - Objective evaluation of images is one of the most essential and practical aspects of image inpainting. The existing objective evaluation methods of image...