Probabilistic opposition-based particle swarm optimization with velocity clamping

A probabilistic opposition-based Particle Swarm Optimization algorithm with Velocity Clamping and inertia weights (OvcPSO) is designed for function optimization—to accelerate the convergence speed and to optimize solution’s accuracy on standard benchmark functions. In this work, probabilistic opposition-based learning for particles is incorporated with PSO to enhance the convergence rate—it uses velocity clamping and inertia weights to control the position, speed and direction of particles to avoid premature convergence. A comprehensive set of 58 complex benchmark functions including a wide range of dimensions have been used for experimental verification. It is evident from the results that OvcPSO can deal with complex optimization problems effectively and efficiently. A series of experiments have been performed to investigate the influence of population size and dimensions upon the performance of different PSO variants. It also outperforms FDR-PSO, CLPSO, FIPS, CPSO-H and GOPSO on various benchmark functions. Last but not the least, OvcPSO has also been compared with opposition-based differential evolution (ODE); it outperforms ODE on lower swarm population and higher-dimensional functions.     

State-of-the-art research study for green cloud computing

Although cloud computing has rapidly emerged as a widely accepted computing paradigm, the research on cloud computing is still at an early stage. Cloud computing suffers from different challenging issues related to security, software frameworks, quality of service, standardization, and power consumption. Efficient energy management is one of the most challenging research issues. The core services in cloud computing system are the SaaS (Software as a Service), PaaS (Platform as a Service), and IaaS (Infrastructure as a Service). In this paper, we study state-of-the-art techniques and research related to power saving in the IaaS of a cloud computing system, which consumes a huge part of total energy in a cloud computing system. At the end, some feasible solutions for building green cloud computing are proposed. Our aim is to provide a better understanding of the design challenges of energy management in the IaaS of a cloud computing system.     

Biocontrol Potential of Endophytic Plant-Growth-Promoting Bacteria against Phytopathogenic Viruses: Molecular Interaction with the Host Plant and Comparison with Chitosan

Endophytic plant-growth-promoting bacteria (ePGPB) are interesting tools for pest management strategies. However, the molecular interactions underlying specific biocontrol effects, particularly against phytopathogenic viruses, remain unexplored. Herein, we investigated the antiviral effects and triggers of induced systemic resistance mediated by four ePGPB (Paraburkholderia fungorum strain R8, Paenibacillus pasadenensis strain R16, Pantoea agglomerans strain 255-7, and Pseudomonas syringae strain 260-02) against four viruses (Cymbidium Ring Spot Virus—CymRSV; Cucumber Mosaic Virus—CMV; Potato Virus X—PVX; and Potato Virus Y—PVY) on Nicotiana benthamiana plants under controlled conditions and compared them with a chitosan-based resistance inducer product. Our studies indicated that ePGPB- and chitosan-treated plants presented well-defined biocontrol efficacy against CymRSV and CMV, unlike PVX and PVY. They exhibited significant reductions in symptom severity while promoting plant height compared to nontreated, virus-infected controls. However, these phenotypic traits showed no association with relative virus quantification. Moreover, the tested defense-related genes (Enhanced Disease Susceptibility-1 (EDS1), Non-expressor of Pathogenesis-related genes-1 (NPR1), and Pathogenesis-related protein-2B (PR2B)) implied the involvement of a salicylic-acid-related defense pathway triggered by EDS1 gene upregulation.     

Influence of van der waals heterostructures of 2D materials on catalytic performance of ZnO and its applications in energy: A review

Recently, photocatalysis has received huge attention in order to overcome energy crisis worldwide. Many semiconductors, potential schemes and hierarchies have come to light during past few decades to fabricate efficient catalysts however, among all these methods heterostructures have taken the world by surprise. With the advancement in post-graphene 2D materials, van der Waals heterostructures have come to light exploring enhancement in photocatalysis. During a very short period a number of ZnO-based van der Waal heterostructures have taken the limelight in the field of photocatalysis. First principles calculations and DFT approach towards the heterostructures of GeC, GaN, WSe₂, WS₂ and other layered 2D materials unleased a series of properties and facts for the provision of enhanced catalysis. Reduction in bandgap of ZnO has also been observed which widens the pathways towards visible light irradiation. However, energy applications of zinc oxide are also fascinating feature as it can serve as a photoanode to replace TiO₂. Whereas the famous hydrogen production, batteries and solar cells have also been fabricated by the use of this semiconductor.     

Leaf Image-Based Plant Disease Identification Using Color and Texture Features

Wireless Personal Communications - Identification of plant disease is usually done through visual inspection or during laboratory examination which causes delays resulting in yield loss by the time...     

Grey is the new RGB: How good is GAN-based image colorization for image compression?

Multimedia Tools and Applications - GAN-based image colorization techniques are capable of producing highly realistic color in real-time. Subjective assessment of these approaches has demonstrated...     

Correction to a novel framework for rapid diagnosis of COVID-19 on computed tomography scans

Pattern Analysis and Applications - A correction to this paper has been published: https://doi.org/10.1007/s10044-021-00969-x     

Investigation of charge and current dynamics in PVA–KOH gel electrolyte-based supercapacitor

Journal of Materials Science: Materials in Electronics - Poly-vinyl alcohol (PVA)-based electrolytes can play a vital role in the development of supercapacitors by providing a desirable charge...     

Development of optimized triaxially electrospun titania nanofiber-in-nanotube core-shell structure

One dimensional (1D) nanostructures and its derivatives can be manipulated to serve special functions like hollow structure, and higher surface area. 1D TiO₂ nanotube-in-nanofibers (NF@NT) are developed through triaxial electrospinning followed by a calcination process. A blended solution of polyvinyl pyrrolidone and tetra-butyl titanate is used in outer and inner layers of nanofibers, respectively, while paraffin oil is used in the middle layer. The optimized triaxial nanofibers of 669.4 ± 52.43 nm are developed at 7.5 w/w% concentration, 28 kV applied voltage, and 24 cm spinning distance. TiO₂ NF@NT structure is obtained through calcination of optimized triaxial nanofibers at 550°C. Subsequently, the morphology of TiO₂ NF@NT and its uniform diameter distribution is confirmed through scanning electron microscopy. Fourier-transform infrared spectroscopy results indicates the formation of TiO₂ NF@NT. X-Rays diffraction pattern peaks also reveals the presence of both anatase and rutile crystalline phases. The presence of only titanium (Ti) and oxygen (O) elements in the TiO₂ NF@NT is confirmed through energy dispersive X-ray spectroscopy. Brunauer–Emmett–Teller analysis indicates that TiO₂ NF@NT has a higher specific surface area of ~141.68 m²/g compared with the solid TiO₂ nanofiber (~75.31 m²/g). This study can be adopted to develop TiO₂ NF@NT for wide range of application.     

Influence of B-site cations ordering on magnetization and dielectric relaxations in Li–Ni spinel ferrites

Ho-substituted Li–Ni ferrites with composition L i_1.2Ni_0.4Ho_xFe_2-xO₄; 0≤ x ≤ 0.15 were synthesized by a self-ignited sol-gel process. An annealing temperature of 950 °C is estimated via thermal-gravimetric (TGA) analysis. X-ray diffraction (XRD) scans have confirmed the formation of the ferrite phase with a spinel structure in all samples. Substitution of Ho ions on the B-site significantly reduced the porosity from 38 -to 23% and the crystallite size from 23.4 -to 21.7 nm. Microstructural analysis revealed a denser structure with an increase in Ho content. Dielectric results showed that both the dielectric loss and dielectric constant depict a nonlinear variation with the addition of Ho. Complex impedance behavior with a single semicircle for all samples suggests the predominant effect of the grain boundary mechanism. The substitution of Ho ions in place of Fe ions significantly decreased the electrical conductivity. The anisotropic Ho³⁺ ions reinforce the L-S coupling which consequently enhanced the coercive force from 145 -to 389 Oe, and thus the anisotropy constant.