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NiO nanostructure was synthesized using a simple co-precipitation method and was embedded on reduced graphene oxide surface via ultrasonication. Structural investigations were made through X-ray diffraction (XRD) and functional groups were confirmed by Fourier transform infrared spectroscopy (FTIR). XRD analysis revealed the grain size reduction with doping. Fourier transform infrared spectroscopy confirmed the presence of metal-oxygen bond in pristine and doped NiO nanostructure as well as the presence of carbon containing groups. Scanning electron microscopy (SEM) indicated that the particle size decreased when NiO nanostructure was doped with copper. BET surface area was found to increase almost up to 43 m2/g for Cu doped NiO nanostructure/rGO composite. Current-voltage measurements were performed using two probe method. UV–Visible spectroscopic profiles showed the blue and red shift for Cu doped NiO nanostructure and Cu doped NiO Nanostructure/rGO composite respectively. Rate constant for Cu doped NiO nanostructure/rGO composite found to increase 4.4 times than pristine NiO nanostructure.  相似文献   
3.
Abstract

Industry 4.0 aims at providing a digital representation of a production landscape, but the challenges in building, maintaining, optimizing, and evolving digital models in inter-organizational production chains have not been identified yet in a systematic manner. In this paper, various Industry 4.0 research and technical challenges are addressed, and their present scenario is discussed. Moreover, in this article, the novel concept of developing experience-based virtual models of engineering entities, process, and the factory is presented. These models of production units, processes, and procedures are accomplished by virtual engineering object (VEO), virtual engineering process (VEP), and virtual engineering factory (VEF), using the knowledge representation technique of Decisional DNA. This blend of the virtual and physical domains permits monitoring of systems and analysis of data to foresee problems before they occur, develop new opportunities, prevent downtime, and even plan for the future by using simulations. Furthermore, the proposed virtual model concept not only has the capability of Query Processing and Data Integration for Industrial Data but also real-time visualization of data stream processing.  相似文献   
4.
Fabrication and thermal characterization of a resistance temperature detector (RTD) heater and microthermocouples (MTs) on silicon substrates have been reported in this paper. The influence of film thickness and nickel-gold (Au) electroplating on RTD on its steady-state temperature with respect to its steady-state electrical power input and resistance is studied. Further, the thermal effects of multiple thermocouples in a thermopile as well as the effects of Au layers in the contact pads of the thermopiles on their open-circuit Seebeck voltage are studied. Therein lies the novelty of this paper. The in situ operating relationships for the RTD heater and the MT are provided  相似文献   
5.
Thrombolytic therapy for unstable angina has not gained acceptance as a primary treatment for unstable angina (UA) despite the evidence showing a reduction in mortality when these agents are given for myocardial infarction. The purpose of this review is to examine the clinical value of thrombolytic therapy for UA. The multiple lines of evidence supporting intracoronary thrombus formation as a key mechanism in the pathogenesis of UA are reviewed. Studies examining the effect of thrombolytic therapy on angiographic endpoints have shown little effect on the extent of luminal narrowing, but do reveal a decrease in angiographically detected thrombus. Twelve randomized, controlled trials of thrombolytic agents in 611 UA patients with predefined clinical endpoints have been published. These trials varied widely in design and adjunctive therapy both in treated and control grops. Review of these trials show a tendency to fewer clinical events such as death, infarction, and need for revascularization in treated patients, with a corresponding increase in bleeding complications. Clinical efficacy of thrombolytic therapy cannot be excluded by the available data, perhaps in part because of insufficient numbers of patients treated. Determination of the net clinical value of thrombolytic therapy must await larger and more definitive trials.  相似文献   
6.
In order to monitor sufficiently large areas of interest for surveillance or any event detection, we need to look beyond stationary cameras and employ an automatically configurable network of nonoverlapping cameras. These cameras need not have an overlapping field of view and should be allowed to move freely in space. Moreover, features like zooming in/out, readily available in security cameras these days, should be exploited in order to focus on any particular area of interest if needed. In this paper, a practical framework is proposed to self-calibrate dynamically moving and zooming cameras and determine their absolute and relative orientations, assuming that their relative position is known. A global linear solution is presented for self-calibrating each zooming/focusing camera in the network. After self-calibration, it is shown that only one automatically computed vanishing point and a line lying on any plane orthogonal to the vertical direction is sufficient to infer the dynamic network configuration. Our method generalizes previous work which considers restricted camera motions. Using minimal assumptions, we are able to successfully demonstrate promising results on synthetic, as well as on real data.  相似文献   
7.
The influence of ferrite-martensite microstructural morphology, volume fraction of martensite, epitaxial ferrite on the tensile behaviour of dual-phase steels, was studied. It was observed that increasing the martensite content and its aspect ratio raised tensile strength and ductility. Epitaxial ferrite in rolled material strongly reduced the strength and improved the ductility, suggesting that substructure strengthening of material, as well as increased stress transfer to the hard phase, contribute to the strength of thermo-mechanically processed material. Mettallographic analysis of deformed samples revealed that void nucleation occurs predominantly along the ferrite-martensite interface. The void density in the necked region increased towards the fracture surface in all samples and was higher for samples which exhibited localized necking.  相似文献   
8.
The Journal of Supercomputing - Agile software development (ASD) and software product line (SPL) have shown significant benefits for software engineering processes and practices. Although both...  相似文献   
9.
Neural Computing and Applications - Detecting and correcting misspelled words in a written text are of great importance in many natural language processing applications. Errors can be broadly...  相似文献   
10.
Radio frequency identification (RFID) tag delegation enables a centralized back-end server to delegate the right to identify and authenticate a tag to specified readers. This should be used to mitigate the computational load on the server side and also to solve the issues in terms of latency and dependency on network connectivity. In this study, we describe a basic RFID delegation architecture and then under this model, we investigate the security of an RFID delegation protocol: Song Mitchell delegation (SMD), which is recently proposed by Song and Mitchell. We point out security flaws that have gone unnoticed in the design and present two attacks namely, a tag impersonation attack and a desynchronization attack against it. We also discover a subtle flaw by which a delegated entity can still keep its delegation rights after the expire of them—this infringes security policy of the scheme. More precisely, we show that the protocol will be still vulnerable to previously mentioned attacks, even if the back-end server ends the delegation right of a delegated reader and update the secrets of the delegated tags. To counteract such flaws, we improve the SMD protocol with a stateful variant so that it provides the claimed security properties.  相似文献   
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