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21.
Internet of Everything (IoE) indicates a fantastic vision of the future, where everything is connected to the internet, providing intelligent services and facilitating decision making. IoE is the collection of static and moving objects able to coordinate and communicate with each other. The moving objects may consist of ground segments and flying segments. The speed of flying segment e.g., Unmanned Ariel Vehicles (UAVs) may high as compared to ground segment objects. The topology changes occur very frequently due to high speed nature of objects in UAV-enabled IoE (Ue-IoE). The routing maintenance overhead may increase when scaling the Ue-IoE (number of objects increases). A single change in topology can force all the objects of the Ue-IoE to update their routing tables. Similarly, the frequent updating in routing table entries will result more energy dissipation and the lifetime of the Ue-IoE may decrease. The objects consume more energy on routing computations. To prevent the frequent updation of routing tables associated with each object, the computation of routes from source to destination may be limited to optimum number of objects in the Ue-IoE. In this article, we propose a routing scheme in which the responsibility of route computation (from neighbor objects to destination) is assigned to some IoE-objects in the Ue-IoE. The route computation objects (RCO) are selected on the basis of certain parameters like remaining energy and mobility. The RCO send the routing information of destination objects to their neighbors once they want to communicate with other objects. The proposed protocol is simulated and the results show that it outperform state-of-the-art protocols in terms of average energy consumption, messages overhead, throughput, delay etc.  相似文献   
22.
The effect of anisole/decane binary solvent mixture and the subsequent addition of low wt% aPS on 6,13-bis(triisopropylsilylethynyl)-pentacene (TIPS-pentacene) thin film morphology is investigated by optical microscopy, AFM and UV–Vis measurements. We show that, over the composition range anisole/decane of 96/4 to 85/15 wt%, the solution maintains an azeotropic composition with the boiling point of the binary mixture remaining constant at 152 °C, and the solvent composition remaining constant during evaporation and drying. It was found that addition of up to 20 wt% decane has little impact on micro-scale crystal morphology but has a significant influence on the growth mode and terrace roughness. The formation of large crystals is explained in terms of the change in solvent, increase in decane content, weakening the solute–solvent interactions and promoting efficient nucleation of the favoured H-aggregates of TIPS-pentacene. The effect of the TIPS-pentacene—aPS ratio up to 20 wt% for drop-cast thin film was similarly investigated. It is found that addition of aPS has a significant effect on both macroscopic crystal properties such as surface coverage, unity of orientation and long range order. It also changes the surface morphology and layer ordering on the nano-scale.  相似文献   
23.
Eldera  Samah S.  Alharbi  Omar A.  Rüssel  C.  Al-wafi  Reem  Hamzawy  Esmat M. A. 《SILICON》2020,12(5):1051-1057
Silicon - Stable cordierite glass-ceramics were prepared from natural kaolin, silica sand and magnesite as raw materials. Furthermore the effect of fluorine additions was tested by addingAlF3 or...  相似文献   
24.
Two different phases of copper molybdate nanoparticles such as Cu3Mo2O9 and Cu6Mo5O18 were synthesized through schematic hydrothermal treatment. The obtained product morphology was explored by using surfactants like sodium lauryl sulfate (SDS) and polyvinylpyrrolidone (PVP). The structural, optical, vibrational and morphological properties were confirmed employing standard characterization techniques. Rectangular nanoflakes of the obtained product were confirmed by employing Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) studies. Selected area electron diffraction (SAED) pattern confirms obtained product crystalline nature. The better morphology controlled sample gives higher 227 mA/g current density at 10 mV/s and small 184 V overpotential. Long duration stability over 16 h was exhibited by Cu6Mo5O18 electrode. Hence, Cu6Mo5O18 electrode shows better electrochemical activity with stunning low overpotential. It would be suggested that PVP surfactant is quite optimum to produce efficient Cu6Mo5O18 catalysts for electrochemical water splitting applications.  相似文献   
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26.
Limbal Stem Cell Deficiency (LSCD) is an eye disease that can cause corneal opacity and vascularization. In its advanced stage it can lead to a degree of visual impairment. It involves the changing in the semispherical shape of the cornea to a drooping shape to downwards direction. LSCD is hard to be diagnosed at early stages. The color and texture of the cornea surface can provide significant information about the cornea affected by LSCD. Parameters such as shape and texture are very crucial to differentiate normal from LSCD cornea. Although several medical approaches exist, most of them requires complicated procedure and medical devices. Therefore, in this paper, we pursued the development of a LSCD detection technique (LDT) utilizing image processing methods. Early diagnosis of LSCD is very crucial for physicians to arrange for effective treatment. In the proposed technique, we developed a method for LSCD detection utilizing frontal eye images. A dataset of 280 eye images of frontal and lateral LSCD and normal patients were used in this research. First, the cornea region of both frontal and lateral images is segmented, and the geometric features are extracted through the automated active contour model and the spline curve. While the texture features are extracted using the feature selection algorithm. The experimental results exhibited that the combined features of the geometric and texture will exhibit accuracy of 95.95%, sensitivity of 97.91% and specificity of 94.05% with the random forest classifier of n = 40. As a result, this research developed a Limbal stem cell deficiency detection system utilizing features’ fusion using image processing techniques for frontal and lateral digital images of the eyes.  相似文献   
27.
Journal of Materials Science: Materials in Electronics - Our articles describe the casting process for producing polyvinyl alcohol (PVA)/polyethylene oxide (PEO)/graphene nanoplates (GNPTs)...  相似文献   
28.
Polyzwitterionic biomaterial with pH-responsive and hemocompatible dual functions is formulated by the copolymerization of 2-(N, N-dimethyl amino) ethyl methacrylate (DMAEMA) sequences and sulfobetaine methacrylate (SBMA) moieties. Hydrogels are salt responsive, due to the interplay between hydrogen bonds formation, ions solvation, and antipolyelectrolyte effect, while DMAEMA sequences provide pH-responsiveness. Their low-fouling nature is demonstrated using plasma proteins and bacteria. Improved hemocompatibility with SBMA content is unveiled by the resistance to platelet and erythrocyte attachment, as well as from delayed plasma clotting time. Overall, this study suggests that dual-functional zwitterionic hydrogels are promising pH-responsive and hemocompatible polymeric biomaterials.  相似文献   
29.
This paper describes the adsorption of lead and cadmium ions from an aqueous solution using a composite of titanium dioxide (TiO2)-incorporated polyacrylonitrile (PAN) electrospun nanofibers. Adsorption capacities and the mechanical response of the PAN/TiO2 composite electrospun nanofibers are investigated at different weight percentages of TiO2 (0.5, 1.0, 2.0, and 5.0 wt.%). The adsorption capacities of the composite PAN/TiO2 (2.0 and 5.0 wt.%) for Pb(II) and Cd(II) are remarkably increased by approximately 114 and 47%, respectively, compared to those of pure PAN electrospun nanofibers. Moreover, the adsorption of Pb(II) and Cd(II) by PAN/TiO2 nanofibers reaches an equilibrium within 60 min, and the process can be described using the nonlinear pseudo-second-order kinetic model. The adsorption isotherm study can be represented by the Langmuir model, which suggests the homogeneous distribution of monolayer adsorptive sites on the composite nanofiber surface. Furthermore, the ultimate tensile strength and ductility of all nanofiber membranes are measured through a uniaxial tension test. Mechanical tests reveal a reduction in the tensile strength of the PAN/TiO2 composite nanofibers with increase in TiO2 amount due to the possible formation of agglomerates and voids in the nanofiber structure.  相似文献   
30.
One of the main challenges associated with e-government adoption is lack of security. Thus, the aim of this research is to investigate the role of security in e-government adoption by integrating security, trust and privacy with the Unified Theory of Acceptance and Use of Technology 2 (UTAUT2). In addition, this research will also investigate the factors that influence the end users’ perception of e-government security. Thus, the research starts with a qualitative study to investigate security antecedents, and this is followed by a quantitative study to validate the qualitative study and determine the role of security in e-government adoption. Data from 625 Saudi citizens were gathered and used in the model assessment. The findings show that user interface quality, security culture and cybersecurity law positively affect security perception. In addition, security perception was found to have a strong effect on trust. Trust is ranked as the third most critical factor affecting behaviour intention after performance expectance and habit. The results make a significant contribution to academic research and have practical implications regarding understanding the role of security in e-government adoption and the factors that affect end users’ perception in e-government security.  相似文献   
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