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Panchaphongsaphak B. Riener R. Ullmer B. Burgkart R. Ravi N. 《Pervasive Computing, IEEE》2008,7(3):70-71
This issue's works in progress department features a novel technology that embeds a six-degrees-of-freedom force-torque sensor into a physical artifact to transform existing 3D passive artifacts into contact-sensitive interface devices. The department also presents an approach for rewriting binary to better correlate application usage with contextual information. 相似文献
104.
Shawn Madtha Curtis Lee K. S. Ravi Chandran 《Journal of the American Ceramic Society》2008,91(4):1319-1321
A comprehensive report on the physical and mechanical properties of titanium boride (TiB), including many recent results that were largely determined in our research, is provided. Fully dense TiB was synthesized by reaction sintering of Ti and TiB2 powders. A bulk nanostructured TiB ceramic material having a microstructure composed of nanosized and interconnected TiB whiskers was created. The TiB produced by this method has properties comparable with that of certain commercial types of silicon nitride. 相似文献
105.
Ravi Sundaram 《Architectural Design》2007,77(6):30-33
Over the last decade in India, intensive urbanisation, with the aid of the mass media, has unleashed a new culture of fear. Widespread access to TV, text messaging and the Internet have heightened and played upon individuals' anxieties. Ravi Sundaram describes how in Delhi, in particular, the media provided the catalyst for ‘mass hysteria’ and ‘psychosis’ during the summer of 2002. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
106.
Anil G. Khadakkar K. Ravi Sankar P. Rathinam R. Narayanan S. P. Rao J. K. Popli 《Strain》1997,33(2):57-60
This paper describes an experimental investigation carried out involving instrumentation, measurement and monitoring of stresses in a large diameter gas pipeline during its lowering operations. It also highlights the ingenious techniques developed and adopted to overcome the difficulties pertaining to long leadwires, measurement of existing strains on the curved surface of a pipeline and protection of strain gauge installations. These novel methods were used to ensure smooth and proper functioning of strain gauge instrumentation even under the severe field conditions at site for more than two weeks, till the lowering operations and pipeline monitoring was successfully completed. 相似文献
107.
Bearing-only passive target tracking is a well-known underwater defence issue dealt in the recent past with the conventional nonlinear estimators like extended Kalman filter (EKF) and unscented Kalman filter (UKF). It is being treated now-a-days with the derivatives of EKF, UKF and a highly sophisticated particle filter (PF). In this paper, two novel methods based on the Estimate Merge Technique are proposed. The Estimate Merge Technique involves a process of getting a final estimate by the fusion of a posteriori estimates given by different nonlinear estimates, which are in turn driven by the towed array bearing-only measurements. The fusion of the estimates is done with the weighted least squares estimator (WLSE). The two novel methods, one named as Pre-Merge UKF and the other Post-Merge UKF, differ in the way the feedback to the individual UKFs is applied. These novel methods have an advantage of less root mean square estimation error in position and velocity compared with the EKF and UKF and at the same time require much lesser number of computations than that of the PF, showing that these filters can serve as an optimal estimator. A testimony of the afore-mentioned advantages of the proposed novel methods is shown by carrying out Monte Carlo simulation in MATLAB R2009a for a typical war time scenario. 相似文献
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109.
Sanjay Sahare Ravi Kant Choubey Gurunath Jadhav Tejashree M. Bhave Samrat Mukherjee Sunil Kumar 《Journal of Superconductivity and Novel Magnetism》2017,30(6):1439-1446
In this report, we studied various structural and optical properties of pure and copper-doped cadmium oxide (CdO) thin films. Nanostructured Cu-doped CdO films were deposited using sol–gel spin-coating technique. The structural and morphological changes have been observed by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and atomic force microscopy (AFM) studies. The optical and electrical properties of the pure and Cu-doped CdO thin films were studied by UV–vis spectroscopy and four-point probe method, respectively. The XRD peaks show the formation of nanocrystalline CdO with cubic face-centered crystal structure. The band gaps of the as deposited films were found in the range of 2.32–2.73 eV, while after doping, it decreases due to structural deformation. The electrical resitivity was found to decrease approximately ~10 in Cu-doped CdO thin films. 相似文献
110.
Zinc oxide-based superhydrophobic surfaces were fabricated on aluminium oxide-seeded glass substrates via sonochemical approach by varying the parameter, the sonication time duration. The fabricated structures have nanowall-like morphology with an average long axis length and thickness of \({\sim }300\) and \({\sim }40~\hbox {nm}\), respectively. The surface roughness created by surface-modified ZnO nanowalls and the air pockets trapped within the dense nanowalls, transformed the hydrophobic glass substrates into superhydrophobic surfaces with water contact angle of \(156{^{\circ }}\) during 20 min of sonication. An independent analysis was carried out to study the growth of ZnO nanowalls over glass substrates in the absence of the aluminium oxide seed layer and sonication process. The results suggested that the synergistic effect of the aluminium oxide seed layer and sonochemical process can enable the formation of ZnO nanowall structures favourable for superhydrophobic property. A possible growth mechanism of ZnO nanowalls formation during sonication process has been discussed in detail. 相似文献