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121.
In multimedia communication, significance of the images for data representation is noteworthy. In this context, secure transmission of images over open channel has become a challenging task. Creation of different strategies in improving the secure image transmission always has a demand. The proposed work suggests an RGB image encryption with the confluence of attractors and hardware triggered key image in which confusion and diffusion were accomplished by Lorenz, Lü and Cellular Automata attractors. The uniqueness of proposed encryption scheme is a key image generation module through cascaded Ring Oscillator circuit which creates M?×?N key image for diffusion of pixels. Facilitating the authenticated networked access to key image generation hardware enables the secure server-client architecture for a variety of secure image transfer applications. The proposed approach is a hardware – software codesign which possesses a good keyspace, improved key sensitivity and satisfies the various statistical parameters thus offering substantial resistance to differential, occlusion and chosen plaintext attacks on RGB images.  相似文献   
122.
Wireless Personal Communications - Spectrum scarcity and the number of mobile users accessing the spectrum are increasing radically, as a complement to this, under utilization of the licensed...  相似文献   
123.
Wireless Sensor Network (WSN) comprises a massive number of arbitrarily placed sensor nodes that are linked wirelessly to monitor the physical parameters from the target region. As the nodes in WSN operate on inbuilt batteries, the energy depletion occurs after certain rounds of operation and thereby results in reduced network lifetime. To enhance energy efficiency and network longevity, clustering and routing techniques are commonly employed in WSN. This paper presents a novel black widow optimization (BWO) with improved ant colony optimization (IACO) algorithm (BWO-IACO) for cluster based routing in WSN. The proposed BWO-IACO algorithm involves BWO based clustering process to elect an optimal set of cluster heads (CHs). The BWO algorithm derives a fitness function (FF) using five input parameters like residual energy (RE), inter-cluster distance, intra-cluster distance, node degree (ND), and node centrality. In addition, IACO based routing process is involved for route selection in inter-cluster communication. The IACO algorithm incorporates the concepts of traditional ACO algorithm with krill herd algorithm (KHA). The IACO algorithm utilizes the energy factor to elect an optimal set of routes to BS in the network. The integration of BWO based clustering and IACO based routing techniques considerably helps to improve energy efficiency and network lifetime. The presented BWO-IACO algorithm has been simulated using MATLAB and the results are examined under varying aspects. A wide range of comparative analysis makes sure the betterment of the BWO-IACO algorithm over all the other compared techniques.  相似文献   
124.
Evolution of the laminated woven natural fiber fabric-reinforced polymer composite structures makes a way to the development of the non-uniform laminated composite structures in order to achieve the stiffness variation throughout the structure. An attempt is made in this work to carry out the experimental and numerical investigations on the dynamic characteristics of the thickness-tapered laminated woven jute/epoxy and woven aloe/epoxy composite plates. The governing differential equations of motion for the thickness-tapered laminated composite plate are developed using the h-p version FEM based on higher order shear deformation theory. The validation of the present finite element formulation is carried out by comparing the natural frequencies obtained using the finite element formulation with those natural frequencies determined experimentally. The developed model is further validated with the available literature works on tapered composite plate to confirm the efficiency of h-p version FEM. This work also explores the study of the vibrational characteristics of composite plates under the influence of plant fiber’s transverse isotropic material characteristics and porosity associated with plant fiber composites through the elastic constants evaluated in the author’s previous work. Also the influences of aspect ratios, ply orientations, and taper angles under various end conditions on the natural frequencies of the woven jute/epoxy composite plate are studied using the present finite element formulation. The forced vibration response of the thickness-tapered laminated woven jute/epoxy composite plate under the harmonic force excitation is carried out considering CFCF and CFFF end conditions.  相似文献   
125.
The main selection criterion for pumps in reprocessing applications is the absence of any moving parts or the moving parts not having any direct contact with the process fluid. There are different types of fluidic pumps such as vortex diode, reverse flow diode, etc. In this work, a new design of helical coil fluidic pump has been developed and demonstrated. Helical coils are widely used in process industries as heat exchangers, reactors, motionless mixers, etc. It is for the first time that the authors are proposing the use of helical coil as a fluidic pump based on its inherent property of high pressure drop as compared to a straight tube. The main objective of this work is to develop an alternate pumping system for reprocessing applications to replace the conventional air lift pump. The helical coil based fluidic diode pump was made up of SS 304 seamless pipe (pipe inner diameter is 9.5 mm) with a 36 mm diameter of helical coil and pitch of 14 mm. In this work, friction factor for the given helical coil was measured from pressure drop experiments. This information was also useful for understanding the transition of the laminar to turbulent region. In order to propose the operating region, the pumping capacity was measured for the helical coil based fluidic pump at different operating conditions. Experimental results show that the proposed hardware is able to pump up to 54 dm3/h. Recommendations have been made for proposing an optimum design.  相似文献   
126.
The present numerical investigation has focused on the magnetohydrodynamics flow of a viscous nanofluid over a stretching wedge with the boundary convective conditions, thermal radiation, and ohmic heating. Buongiorno's two-component nonhomogeneous nanoscale model was used and a dilute nanofluid with spherical type particles is considered. Similarity transformations are used to render the system of governing partial differential equations into a system of coupled similarity equations. The transformed equations are solved numerically with the BVP4C method. Validation of solutions with previous studies based on special cases of the general model is included. The salient features of fluid velocity profile, temperature as well as concentration profiles are discussed in a graphical manner for various values of selected governing factors. The skin friction coefficient, mass, and heat transfer rates are calculated and summarized. It is worthwhile noticing that the validation results exhibit an excellent agreement with already existing reports. The modeling of the present problem is useful in the thermal processing of sheet-like substances that is a necessary operation in paper procurement, wire drawing, drawing of plastic films, polymeric sheets, and metal spinning.  相似文献   
127.
Wireless Personal Communications - Nowadays System-on-Chip (SoC) is an emerging technology in the world of Integrated Chip manufacturers. In SoC, many IP cores are integrated inside a chip. The...  相似文献   
128.
Innate immune receptors initiate a host immune response, or inflammatory response, upon detecting pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs). Among the innate immune receptors, nucleotide-binding oligomerization domain (NOD)-like receptors (NLRs) play a pivotal role in detecting cytosolic PAMPs and DAMPs. Some NLRs can form a multiprotein cytosolic complex known as the inflammasome. Inflammasome activation triggers caspase-1–mediated cleavage of the pore-forming protein gasdermin D (GSDMD), which drives a form of inflammatory cell death called pyroptosis. Parallelly, activated caspase-1 cleaves immature cytokines pro–IL-1β and pro–IL-18 into their active forms, which can be released via GSDMD membrane pores. The NLR family apoptosis inhibitory proteins (NAIP)-NLR family caspase-associated recruitment domain-containing protein 4 (NLRC4) inflammasome is important for mounting an immune response against Gram-negative bacteria. NLRC4 is activated through NAIPs sensing type 3 secretion system (T3SS) proteins from Gram-negative bacteria, such as Salmonella Typhimurium. Mutations in NAIPs and NLRC4 are linked to autoinflammatory disorders in humans. In this review, we highlight the role of the NAIP/NLRC4 inflammasome in host defense, autoinflammatory diseases, cancer, and cell death. We also discuss evidence pointing to a role of NLRC4 in PANoptosis, which was recently identified as a unique inflammatory programmed cell death pathway with important physiological relevance in a range of diseases. Improved understanding of the NLRC4 inflammasome and its potential roles in PANoptosis paves the way for identifying new therapeutic strategies to target disease.  相似文献   
129.
Nanostructured materials with high aspect ratio and one-dimensional (ID) morphology are nature’s choices when high degree of functional performances and flexible properties are concerned. Two examples are extracellular matrices in tissues of living organism, and light harvesting rods of the retina and chlorophyll. Electrospinning (E-spinning) is a simple processing technique that allows fabrication of high aspect ratio nanofibers (NFs) in a commercial scale. Electrospun nanofibers (E-spun NFs) combine a number of physical properties such as guided electron transport, strain-induced electronic properties, high mechanical strength, high degree of flexibility, large specific surface area, high electron and thermal diffusivity, and tailorable pore distribution. Our laboratory has been involved in fabrication of E-spun polymeric, inorganic, and polymer-nanocomposite fibers in random, aligned, cross-aligned, sheaths, tubes, yarns, core/shell, and trilayer morphologies. This article focuses on application of the E-spun fibers in the areas of clean energy, water treatment, and regenerative medicine in the authors’ laboratory. In addition, the article briefly reviews the progress made in these areas using E-spun NFs.  相似文献   
130.
Natural dyes find use in the coloring of textiles, drugs, cosmetics, etc. Owing to their nontoxic effects, they are also used for coloring various food products. In the present study antimicrobial properties of 8 food dyes against 10 bacteria and 5 fungal organisms were investigated. It was observed that red dyes showed best antibacterial activity while yellow dyes showed better antifungal activity. Dyes obtained from catechu (Acacia catechu) and myrobalan (Terminalia chebula) is not sufficiently effective against the tested microorganisms. In addition to antimicrobial analysis, antioxidant activity by 3 different methods was also investigated. In all the methods, red dye was found to have greater antioxidant activity. It suggest that the addition of these dyes in food not only enhances the value addition by making the food more presentable but also shall address the issue of food supplementation with substances that are good antibiotics and antioxidants, subsequently proving to be health benefactors.  相似文献   
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