EARP: An Enhanced ACO-Based Routing Protocol for Wireless Sensor Networks with Multiple Mobile Sinks

A plenty of Ant Colony Optimization (ACO)-based routing algorithms have been proposed to find optimal path of mobile sinks in Wireless Sensor Networks (WSNs). However, they concentrate on energy efficiency and ignore fault tolerance for critical data collection points like Cluster Heads (CHs). They supposed an ideal scenario where there are no failures which is not the case in reality due to failures resulting from unattended and hostile deployment environments and so on. Moreover, the existing routing protocols are not application-specific enabled (i.e., the parameters cannot be adapted to the application’s requirements). In this paper, we propose an energetically-optimized multi-sink-based clustered WSN model along with a fault-tolerant and energy-efficient Enhanced ACO based Routing Protocol (EARP) to provide reliable data transmission in case of encountering a faulty path. Unlike existing studies, EARP addresses jointly the different constraints of forest fires detection application like fault tolerance, network lifetime and response time. The proposed EARP is simulated along with its counterparts in a general scenario based on various main metrics and also in an application-specific scenario (forest fires detection) based on network lifetime and response time. The simulations results prove its superiority, compared to its peers, in both scenarios.

     

Pansharpening multispectral remote sensing data by multiplicative joint nonnegative matrix factorization

Pansharpening aims at combining observable panchromatic and multispectral images to generate an unobservable image with the high spatial resolution of the former and the spectral diversity of the latter. In this paper a new fusion method is proposed. This method, related to linear spectral unmixing (LSU) techniques and based on non-negative matrix factorization (NMF), optimizes, by new iterative–multiplicative update rules, a joint criterion that exploits a spatial degradation model between the two images. The proposed Multiplicative Joint Non-negative Matrix Factorization (MJNMF) approach is applied to synthetic and real data, and its effectiveness in spatial and spectral domains is evaluated with commonly used performance criteria. Experimental results show that the proposed method yields good spectral and spatial fidelities of the pansharpened data. Also, it outperforms those tested from the literature.     

Relaxation dynamic and electrical mobility for poly(methyl methacrylate)‐polyaniline composites

Composites of emeraldine form of polyaniline (PAni) and poly(methyl methacrylate) (PMMA) are prepared by emulsion polymerization method in definite ratios. The chemical structure of the samples and their morphologies have been investigated by different techniques including FTIR, UV–vis, XRD, SEM, and TGA. Enhancement in thermal stability of the obtained composites by PAni additions has been confirmed. Alpha analyzer, in frequency range 0.1 Hz to 20 MHz, was employed to investigate the molecular dynamics of the prepared samples and the accompanied electrical conductivity at temperatures ranging from 223 to 423 K. Conductivity investigations showed that mobility has the more dominant effect on the charge transportation. The dynamic peak at lower temperatures of the PMMA has high activation energy (83.8 kJ/mol). While, Maxwill‐Wagner‐Siller process due to the interfacial polarization in the composites has only 7.5 kJ/mol activation energy. This is a clear indication of the ease of the investigated dynamic. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45415.     

Reactions of unsaturated compounds I. Structure and chromic acid oxidation of the hydrocarbon C17H18 obtained by the dehydration of 1,1-diphenyl-2,2-dimethylpropan-1-ol

Dehydration of the carbinol 1,1-diphenyl-2,2-dimethylpropan-1-ol gives a hydrocarbon C₁₇H₁₈ which was identified as 2-methyl-3,3-diphenylbut-1-ene. Oxidation of C₁₇H₁₈ with chromium trioxide in acetic anhydride gave acetone, acetophenone, benzophenone and α-methyl-β,β-diphenylbutyric acid. Oxidation with chromium trioxide in aqueous sulphuric acid gave acetone, acetophenone, benzophenone and diphenylmethylacetic acid. A tentative explanation for the production of abnormal fission products and α-methyl-β,β-diphenylbutyric acid is given.     

Nd:YAG laser alloying of high-speed steel tools with BN and Ti/BN and the effects on turning performance

A 400 W pulsed Nd:YAG laser was used to surface alloy BN and Ti/BN on AISI M2 steel using hexagonal BN powder and Ti foil (25 μm thickness). The clearance (flank) faces of the single-point tool were laser alloyed using BN and Ti/BN. Optical metallography, scanning electron microscope, Vicker's microhardness and X-ray diffraction were employed to characterize the alloyed layers. The depths of the laser-alloyed zones of BN- and Ti/BN-alloyed tools were about 140 μm and 260 μm respectively. The hardness of the laser-alloyed layer with BN was about 640 HV while that of the alloyed layer with Ti/BN was about 680 HV. The alloyed layers were free from cracks and porosity. Both the alloyed and unalloyed tools were then tested on a 14.7 kW engine lathe to turn AISI 1045 steel workpieces. The results indicated that the tool life of BN-alloyed tools was about 200% higher than that of the unalloyed tools, while the tool life of Ti/BN-alloyed tools was about 260% higher when the tool life criterion was chosen as 0.3 mm flank wear. Also, the tool wear rate was reduced by about 30% and 50% for BN-and Ti/BN-alloyed tools, respectively. The reduction in tool wear of the alloyed tools was attributed to a reduction of the chip-tool contact length (and consequently the reduction of coefficient of friction between the tool and workpiece material) and to the different chip formation mechanisms.     

Boundary control of a parallel-flow heat exchanger by input–output linearization

A design of the control of the internal fluid temperature at the outlet of a parallel-flow heat exchanger by manipulating the inlet external fluid temperature is proposed. The dynamic model of the heat exchanger is given by two partial differential equations that are used without spatial discretization to design the control law. Based on nonlinear control, a state-feedback law that ensures a desired performance of a measured output defined as the spatial weighted average temperature of the internal fluid is derived. Then, in order to control the outlet internal fluid temperature, a control strategy is proposed where an external controller is introduced to provide the set point of the considered measured output by taking as input the error between the outlet internal fluid temperature and its desired set point. As the designed control law is a state feedback of distributed nature, for practical application, a Kalman filter is used to reconstruct the entire state of the system from the measurements of the outlet fluids temperatures. The closed-loop system is shown to be exponentially stable. The validity of the proposed control design is examined in simulation by considering the tracking and perturbation rejection problems.     

Early effects of C60 Administration in Swiss Mice: A Preliminary Account for In Vivo C60 Toxicity.

Abstract

High amounts of micronized C₆₀ have been injected intraperitoneally into Swiss mice. Until the fourteenth day, they were still alive without any behaviour trouble. C₆₀ was well absorbed, and found localized in spleen and liver. Inside the liver, C₆₀ was     

Stability of Viscoelastic Fluid Flowing Through Porous Medium Down Non‐uniformly Heated Inclined Plane

The stability of a thin layer of viscoelastic fluid flowing through a porous medium down a non‐uniformly heated inclined plane with a constant temperature gradient along the plane is considered. The film flow system is influenced by gravity, mean surface tension, thermocapillary forces, viscoelastic forces, porosity, and permeability of porous medium. We seek a solution of the stability problem in a series in small wave numbers, and the obtained results, when the plane is heated in the downstream direction, show that the Marangoni, Galileo, and Biot numbers, porosity, and permeability of the porous medium have dual roles in the stability of the flow system, while the viscoelastic parameter and angle of inclination have stabilizing effects, and the Prandtl number has a destabilizing effect. The effects of these physical parameters are also discussed in the case when the plane is cooled in the downstream direction, and we found that their effects are opposite to those of the previous case. © 2013 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.21105