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Classification of scenes across multi-sensor remote sensing images with different spatial, spectral, temporal resolutions involves identification of variable length spatial patterns of objects in a scene. So, it necessitates the use of local representations from different regions of a scene in order to comprehend the scene formation. In this paper, we propose a dynamic kernel based representation to handle the patterns of variable lengths in the scenes of remote sensing images. These kernels help to assimilate spatial variability captured using convolutional features in a Gaussian mixture model. The statistics of GMM facilitate the dynamic kernels in preserving the local spatial similarities while handling the changes in spatial content globally within the same scene. The efficacy of the proposed method using two variants of the dynamic kernels is demonstrated on three benchmark scene classification datasets, namely, UCM Land Use (21 classes), Aerial image dataset (30 classes), and NWPU-RESISC45 (45 classes). Our experiments show that the mean interval kernel is better discriminative as it makes use of first and second-order statistics of GMM. © 2021 IEEE.

Representation of spatio-temporal properties of human body silhouette and human-to-ground relationship, significantly contribute to the fall detection process. So, we propose an approach to efficiently model the spatio-temporal features using fall motion vector. First, we construct a Gaussian mixture model (GMM) called fall motion mixture model (FMMM) using histogram of optical flow and motion boundary histogram features to implicitly capture motion attributes in both the fall and non-fall videos. The FMMM contains both fall and non-fall attributes resulting in a high-dimensional representation. In order to extract only the relevant attributes for a particular fall or non-fall videos, we perform factor analysis on FMMM to get a low dimensional representation known as fall motion vector. Using fall motion vector, we are able to efficiently identify fall events in varieties of scenarios, such as the narrow angle camera (Le2i dataset), wide angle camera (URFall dataset), and multiple cameras (Montreal dataset). In all these scenarios, we show that the proposed fall motion vector achieves better performance than the existing methods. © 2001-2012 IEEE.

Digital elevation model (DEM) is used as a source of elevation data in wide range of applications. The applications involving larger area than an individual DEM scene often need a mosaic of DEM scenes. A simple stitching exhibits seams along the borders of DEM scenes in the mosaic output. The presence of seam lines varies with the number of scenes in an overlapping region and their overlap extents. The conventional feathering-based blend method, by virtue of the method itself, considers only two input scenes in an instance of the mosaic process. This method requires a suitable ordering of the input DEM scenes, especially in the overlapping regions containing more than two scenes. In this paper, we propose a framework that automatically handles the multiple overlapping regions and creates a seamless mosaic of Cartosat-1 DEM scenes for a given region of interest. We use a tree data structure to arrange input DEM scenes hierarchically based on their metadata. A traversal algorithm is devised to establish an order of precedence among the DEM scenes. This determines a unique input sequence of DEM scenes during mosaic process. In addition, two variants of feathering-based blend method are formulated to handle all possible cases of the overlapping regions. The experiments have been conducted on Cartosat-1 DEM scenes over 1°×1° region of interest. We analyze and compare our proposed methodology with average method and feathering-based blend method. We demonstrate that our framework exhibits a smooth transition of elevation values in the overlapping regions of the DEM mosaic output.

This study explores the prospects of using scaled model experiments for capturing the influence of a novel spray deflection concept on planing craft performance in calm water and in waves. An experimental setup with a towed planing craft model is designed and systematic experiments are performed, first with a bare hull model and then with the same model equipped with spray deflectors. Measured trim, sinkage and resistance in calm water and accelerations and resistance in waves are presented. The results, as well as various aspects of the experimental setup and the spray phenomenon, are discussed. The experimental results indicate that the studied spray deflector concept can have positive effects by lowering the resistance as well as the acceleration in waves. The detailed tailoring of the deflectors is concluded to be crucial. The developed experimental setup is concluded to give consistent results that capture the influence of the spray deflection details on the craft resistance and responses and is concluded to be useful for further research as well as for design purposes., QC 20200421

Wheat is one of the major sources of food for much of the world. However, because bread wheat's genome is a large hybrid mix of three separate subgenomes, it has been difficult to produce a high-quality reference sequence. Using recent advances in sequencing, the International Wheat Genome Sequencing Consortium presents an annotated reference genome with a detailed analysis of gene content among subgenomes and the structural organization for all the chromosomes. Examples of quantitative trait mapping and CRISPR-based genome modification show the potential for using this genome in agricultural research and breeding. Ramírez-González et al. exploited the fruits of this endeavor to identify tissue-specific biased gene expression and coexpression networks during development and exposure to stress. These resources will accelerate our understanding of the genetic basis of bread wheat.

Wheat is one of the major sources of food for much of the world. However, because bread wheat's genome is a large hybrid mix of three separate subgenomes, it has been difficult to produce a high-quality reference sequence. Using recent advances in sequencing, the International Wheat Genome Sequencing Consortium presents an annotated reference genome with a detailed analysis of gene content among subgenomes and the structural organization for all the chromosomes. Examples of quantitative trait mapping and CRISPR-based genome modification show the potential for using this genome in agricultural research and breeding. Ramírez-González et al. exploited the fruits of this endeavor to identify tissue-specific biased gene expression and coexpression networks during development and exposure to stress. These resources will accelerate our understanding of the genetic basis of bread wheat.

Due to their specific hull form, planing craft are vessels that can overcome wave resistance and reach high operational speeds by transforming the hydrodynamic pressure, unfavourable in terms of resistance, into lift. The different resistance components acting on a planing hull have been studied and modelled in the past. By empirical studies, it is known that a noticeable percentage of the total resistance is caused by the whisker spray resistance, hence, devices to decrease its contribution are of great interest. The most common spray deflection devices applied are spray rails. An innovative spray deflection concept, called deflectors, has been introduced and evaluated using numerical simulations. The present paper considers a systematic towing tank experiment for studying the deflectors and validating the numerical study. Results show that the validation of the numerical test case is not easily obtained. Suggestions for improved approaches for experimental investigations of spray deflectors are discussed., QC 20211020