The numerical prediction of flow and heat transfer in rod-bundle geometries

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Decorrelation of User Defined Function Invocations in Queries

Queries containing user-defined functions (UDFs) are widely used, since they allow queries to be written using a mix of imperative language constructs and SQL, thereby increasing the expressive power of SQL; further, they encourage modularity, and make queries easier to understand. However, not much attention has been paid to their optimization, except for simple UDFs without imperative constructs. Queries invoking UDFs with imperative constructs are executed using iterative invocation of the UDFs, leading to poor performance, especially if the UDF contains queries. Such poor execution has been a major deterrent to the wider usage of complex UDFs

Optimal Capacitor Placement - A Bibliometric Survey

In this paper, Bibliometric survey has been carried out on Optimal Capacitor Placement from 1981 to 2021. Scopus database has been used for the analysis. There were total 909 documents found on the topic of Optimal Capacitor placement. The statistical analysis is carried out source-wise, year-wise, area-wise, Country-wise, University wise, author-wise, and based on funding agency. Network analysis is also carried out based on Co-authorship, Co-occurrence, Citation Analysis and Bibliographic coupling. Results are presented. During 2016, there were 77 documents published which is the highest. International Journal of Electrical Power and Energy Systems of Elsevier has published 37 documents during the period of study which is highest under the category of sources. VOSviewer 1.6.16 is the software that is used for statistical analysis and network analysis on the database. It provides a very effective way to analyze the co-authorship, co-occurrences, citations and bibliometric couplings etc. The source for all Tables and figures is www.scopus.com, The data is assessed on 6th June, 2021

3D discomfort from vertical and torsional disparities in natural images

The two major aspects of camera misalignment that cause visual discomfort when viewing images on a 3D display are vertical and torsional disparities. While vertical disparities are uniform throughout the image, torsional rotations introduce a range of disparities that depend on the location in the image. The goal of this study was to determine the discomfort ranges for the kinds of natural image that people are likely to take with 3D cameras rather than the artificial line and dot stimuli typically used for laboratory studies. We therefore assessed visual discomfort on a five-point scale from ‘none’ to ‘severe’ for artificial misalignment disparities applied to a set of full-resolution images of indoor scenes. For viewing times of 2 s, discomfort ratings for vertical disparity in both 2D and 3D images rose rapidly toward the discomfort level of 4 (‘severe’) by about 60 arcmin of vertical disparity. Discomfort ratings for torsional disparity in the same image rose only gradually, reaching only the discomfort level of 3 (‘strong’) by about 50 deg of torsional disparity. These data were modeled with a second-order hyperbolic compression function incorporating a term for the basic discomfort of the 3D display in the absence of any misalignments through a Minkowski norm. These fits showed that, at a criterion discomfort level of 2 (‘moderate’), acceptable levels of vertical disparity were about 15 arcmin. The corresponding values for the torsional disparity were about 30 deg of relative orientation

In-Cabin Radar Monitoring System: Detection and Localization of People Inside Vehicle using Vital Sign Sensing Algorithm

Radars are used in automobiles for various functionalities, starting from the obstacle alarm during vehicle reversing to advanced functionalities like autonomous driving. A practical method for monitoring people inside a vehicle for various applications (surveillance, safety, etc.) could be built using Radar. This paper presents the embedded implementation of a vital sign sensing algorithm using the radar signal processing (RSP) technique. MEX (MATLAB executable) interface is performed with the embedded C code of the vital sign sensing algorithm generated for validating the results with the RSP technique. Finally, Unit testing is performed on the developed embedded C code of the vital sign sensing algorithm to remove the dead codes and to verify whether all branches and statements in a developed algorithm are working accordingly. The embedded C code results were found to be matching precisely with the RSP technique. With the help of obtained results, we can differentiate between an adult and a baby inside a vehicle

Infrared spectra and thermal decompositions of metal acetates and dicarboxylates

The infrared spectra of rare earth acetates have been studied to examine the metal-acetate bonding. The thermal decomposition of rare earth acetates as well as lead and copper acetates have been investigated in detail by employing thermogravimetric analysis and differential thermal analysis. Thermal decomposition of calcium dicarboxylates (malonate to sebacate) have been studied employing t.g.a. and d.t.a. Infrared spectra of the dicarboxylates have also been studied. Preliminary results on the products of decomposition of dicarboxylates have been reported

Single-Walled Carbon Nanotube Bundles Intercalated with Semiconductor Nanoparticles

Nanoparticles of CdSe, CdS and ZnSe have been incorporated in the inter-tubular gaps of single-walled carbon nanotube (SWNT) bundles. Electron microscope, X-ray diffraction (XRD), electronic spectroscopy and Raman studies have been employed to characterize these systems. The lengths of the intercalate inside the bundles could be varied by changing the reaction conditions. Electronic absorption and photoluminescence studies from the semiconductor intercalates show the expected blue-shift with respect to the corresponding bulk samples in CdS and ZnS samples. The SWNT lattice is expanded on incorporating CdSe as confirmed by XRD in the low-angle range. The expansion in the lattice is also corroborated by the Raman measurements which show a considerable red-shift for both the radial and the tangential modes of the SWNT signal, thus signifying an increase in the van der Waals gap between the tubes in the bundle. The red-shift of the Raman signal is due to the decrease in the inter-tube interactions as well as due to doping effects