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Optimal Feature Selection for the Classification of Hyperspectral Imagery Using Adaptive SpectralSpatial Clustering
Hyperspectral images captured through the hyperspectral sensors play an imperative part in remote sensing applications in the present context. Unlike traditional images sensed with few bands in the visible spectrum, the hyperspectral (HS) images are obtained with hundreds of spectral band ranges from infrared to ultraviolet regions. Because of its vast spatial and spectral data, it requires an extensive computational system for processing and its hidden features are needed to be unveiled in an effective manner specifically for the classification of HS imagery. This approach exploits the high spectral band correlation and rich spatial information of the HS images for the generation of feature vectors. To attain optimal feature space for the best probable classification, an adaptive approach is incorporated to adaptively choose spectralspatial features for feature selection to classify the pixels effectively. Furthermore, the HS image encompasses several bands including noisy bands. To categorize the images with great accuracy, it is suggested to eradicate the noisy bands whilst retaining the informative bands. In this research, an adaptive spectralspatial feature selection scheme is proposed for HS images where the extremely correlated representative bands are considered for analysis with uncorrelated and noisy spectral bands are judiciously discarded during its classification process. This hybrid approach not merely diminishes the computational time and also improves the general classification accuracy significantly. The empirical result displays that the proposed work surpasses the conventional approach of HS image classification systems. 2018, Springer Science+Business Media, LLC, part of Springer Nature. -
Lattice thermal conduction in cadmium arsenide
Lattice thermal conductivity (LTC) of cadmium arsenide (Cd3As2) is studied over a wide temperature range (1-400 K) by employing the Callaway model. The acoustic phonons are considered to be the major carriers of heat and to be scattered by the sample boundaries, disorder, impurities, and other phonons via both Umklapp and normal phonon processes. Numerical calculations of LTC of Cd3As2 bring out the relative importance of the scattering mechanisms. Our systematic analysis of recent experimental data on thermal conductivity (TC) of Cd3As2 samples of different groups, presented in terms of LTC, ? L, using a nonlinear regression method, reveals good fits to the TC data of the samples considered for T < ? 50 K, and suggests a value of 0.2 for the Gruneisen parameter. It is, however, found that for T > 100 K the inclusion of the electronic component of TC, ? e, incorporating contributions from relevant electron scattering mechanisms, is needed to obtain good agreement with the TC data over the wide temperature range. More detailed investigations of TC of Cd3As2 are required to better understand its suitability in thermoelectric and thermal management devices. 2022 Chinese Physical Society and IOP Publishing Ltd. -
Energy-Aware Multilevel Clustering Scheme for Underwater Wireless Sensor Networks
The expansion of wireless sensor networks in the underwater environment resulted in underwater wireless sensor networks. It has dramatically impacted the research arena because of its widespread and real-time applications. But successful implementation of underwater wireless sensor networks faces many issues. The primary concern in the underwater sensor network is sensor nodes' energy depletion problem. In this paper, to improve the lifetime of the underwater wireless sensor network, an Energy-Aware Multi-level Clustering Scheme is proposed. The underwater network region is considered 3D concentric cylinders with multiple levels. Further, each level is divided into various blocks, representing one cluster. The proposed algorithm follows vertical communication mode from the sea bed to the surface area in a bottom-up fashion. Multiple levels with varying heights overcome the communication issues due to high water pressure towards the sea bed. Simulations are carried out to show the efficiency of the proposed algorithm, which performs better in terms of a prolonged network lifetime and average residual energy. The simulation result shows significant improvement in the network lifetime compared with current algorithms. 2013 IEEE. -
Total Global Dominator Coloring of Trees and Unicyclic Graphs
A total global dominator coloring of a graph G is a proper vertex coloring of G with respect to which every vertex v in V dominates a color class, not containing v and does not dominate another color class. The minimum number of colors required in such a coloring of G is called the total global dominator chromatic number, denoted by Xtgd (G). In this paper, the total global dominator chromatic number of trees and unicyclic graphs are explored. 2023 University of Baghdad. All rights reserved. -
Total domination coloring of graphs
A total domination coloring of a graph G is a proper coloring of G in which open neighbourhood of each vertex contains at least one color class and each color class is dominated by at least one vertex. The minimum number of colors required for a total domination coloring of G is called the total domination chromatic number of G and is denoted by ctd(G). In this paper, we study the total domination chromatic number of some graph classes. The bounds of total domination chromatic number with respect to the graph parameters such as the domination number, chromatic number, total dominator chromatic number and total domination number are also studied. 2021 the author(s). -
Green synthesis of Cobalt Oxide nanoparticles with in-vitro cytotoxicity assessment using pomegranate (Punica granatumL.) seed oil: A promising approach for antimicrobial and anticancer applications
Green synthesis of nanoparticles and their pharmacological implementation have gained importance in the field of nanotechnology. This study primarily aims to explore the use of Punica granatum L. seed oil as a reducing agent for the synthesis of cobalt nanoparticles, making it both economically and pharmacologically valuable. Gas chromatography-mass spectroscopy analysis was carried out to study the active metabolites present in P. granatum seed oil. The green synthesis of cobalt nanoparticles was established based on the color change of the reaction mixture from dark green to light green. These particles showed a ?max at 279.88 nm for UV-visible spectrometry analysis. Furthermore, X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscope (FE SEM) and Dynamic Light Scattering (DLS) were performed to confirm the nature of these nanoparticles. The pharmacological potential of these cobalt oxide nanoparticles was tested against microbial pathogens. The results suggest that these nanoparticles exhibited significant activity against various human bacterial and fungal pathogens. Additionally, in in vitro cytotoxicity analysis, demonstrated that CoONPs selectively targeted MCF-7 cancer cells with a significant IC50 value compared to non-cancerous cells (L929). In conclusion, this study demonstrated that green synthesized CoONPs using P. granatum show significant potential against eukaryotic cancer cells and microbial pathogens. Furthermore, this study has implications for medical research centers and pharmaceutical industries in addressing modern challenges such as increasing antibiotic resistance in communities. 2024 Horizon e-Publishing Group. All rights reserved. -
Nutritional, biochemical and antioxidant activities of edible and non-edible parts of Punica granatum L.
In the present study, the nutritional profiling and antioxidant analysis of the different parts of Punica granatum was done. In the nutritional profiling, different percentages of moisture content was found in the flower (9.63%), leaf (9.17%), peel (5.34%), root (8.08%), stem (4.09%) and fruit (3.54%). Ash content was recorded higher in the stem (30%/g) followed by root, leaf, flower, fruit and peel. Also, the major and minor elements like nitrogen, potassium, calcium, phosphorus, magnesium, sulphur, zinc, copper, manganese and iron were analysed in different parts of P. granatum. The fruit recorded the highest amount of nitrogen (5.710.01%) and phosphorus (5.710.01%) whereas peel was recorded with more potassium (0.990.01%). The phytochemical quantification showed the major content of carbohydrates in the flower (317.96 mg/g) and leaf (315.62 mg/g). The protein was recorded higher in fruit (69 mg/g) and proline in root (19.54 mg/g). The TPC was recorded more in the peel (240.72 g/g) followed by the flower (223.05 g/g). P. granatum peel was recorded with maximum flavonoid content (873.13 g/g) and had a higher antioxidative response in comparison to other plant parts of P. granatum. 2024, Indian journals. All rights reserved. -
Gender modulates the development of theta event related oscillations in adolescents and young adults
The developmental trajectories of theta band (4-7. Hz) event-related oscillations (EROs), a key neurophysiological constituent of the P3 response, were assessed in 2170 adolescents and young adults ages 12 to 25. The theta EROs occurring in the P3 response, important indicators of neurocognitive function, were elicited during the evaluation of task-relevant target stimuli in visual and auditory oddball tasks. These tasks call upon attentional and working memory resources. Large differences in developmental rates between males and females were found; scalp location and task modality (visual or auditory) differences within males and females were small compared to gender differences. Trajectories of interregional and intermodal correlations between ERO power values exhibited increases with age in both genders, but showed a divergence in development between auditory and visual systems during ages 16 to 21. These results are consistent with previous electrophysiological and imaging studies and provide additional temporal detail about the development of neurophysiological indices of cognitive activity. Since measures of the P3 response has been found to be a useful endophenotypes for the study of a number of clinical and behavioral disorders, studies of its development in adolescents and young adults may illuminate neurophysiological factors contributing to the onset of these conditions. 2015 Elsevier B.V. -
Genetic correlates of the development of theta event related oscillationsin adolescents and young adults
The developmental trajectories of theta band (47Hz) event-related oscillations (EROs), a key neurophysiological constituent of the P3 response, were assessed in 2170 adolescents and young adults ages 12 to 25. The theta EROs occurring in the P3 response, important indicators of neurocognitive function, were elicited during the evaluation of task-relevant target stimuli in visual and auditory oddball tasks. Associations between the theta EROs and genotypic variants of 4 KCNJ6 single nucleotide polymorphisms (SNPs) were found to vary with age, sex, scalp location, and task modality. Three of the four KCNJ6 SNPs studied here were found to be significantly associated with the same theta EROs in adults in a previous family genome wide association study. Since measures of the P3 response have been found to be a useful endophenotypes for the study of a number of clinical and behavioral disorders, studies of genetic effects on its development in adolescents and young adults may illuminate neurophysiological factors contributing to the onset of these conditions. 2016 Elsevier B.V. -
Weakly nonlinear stability analysis of salt-finger convection in a longitudinally infinite cavity
This paper is a two-dimensional linear and weakly nonlinear stability analyses of the three-dimensional problem of Chang et al. ["Three-dimensional stability analysis for a salt-finger convecting layer,"J. Fluid Mech. 841, 636-653 (2018)] concerning salt-finger convection, which is seen when there is sideways heating and salting along the vertical walls along with a linear variation of temperature and concentration on the horizontal walls. A two-dimensional linear stability analysis is first carried out in the problem with the knowledge that the result could be different from those of a three-dimensional study. A two-dimensional weakly nonlinear stability analysis, that is, then performed points to the possibility of the occurrence of sub-critical motions. Stability curves are drawn to depict various instability regions. With the help of a detailed stability analysis, the stationary mode is shown to be the preferred one compared to oscillatory. Local nonlinear stability analysis of the system is done in a neighborhood of the critical Rayleigh number to predict a sub-critical instability region. The existence of a stable solution at the onset of a weakly nonlinear convective regime is indicated, allowing one to perform a bifurcation study in the problem. Heat and mass transports are discussed by analyzing the Nusselt number, Nu, and Sherwood number, Sh, respectively. A simple relationship is obtained between the Nusselt number and the Sherwood number exclusively in terms of the Lewis number, Le. 2022 Author(s). -
Recommender system for personalised travel itinerary
A recommender system is an approach to give an appropriate solution to a particular problem. This helps in recognising the pattern or behaviour of a user to suggest future possible likes of the user. Nowadays people like to travel during their spare time, it has become a rigid task to decide where to go. This paper represents a customised recommender system to help users in destining their itinerary. A model is designed to suggest the best places to visit in Rome. A questionnaire was prepared to get information about user's interest during their travel. The model generates the best five places to visit with respect to the choice picked by the user. The top five places for each category will be displayed to the user and the user was asked to pick a starting point for the itinerary. Then the model generates another set off a filtered list of places to enhance their travel experience. It includes displaying the top 5 restaurants to visit during their travel. Copyright 2019 Institute of Advanced Engineering and Science. All rights reserved. -
Imprint of Fertiliser Policies on Farming Practices Evidence from the Top Five Consuming States
The policies related to the use of nitrogen fertilisers since independence are reviewed using primary and secondary databases to derive the present status of nitrogen, phosphorus, and potassium fertiliser use among farmers. Recommendations for increasing nitrogen use efficiency in agriculture for sustainability are provided. 2023 Economic and Political Weekly. All rights reserved. -
Assessment of Attitude and Knowledge of Law Students towards Tele-evidence Facility for Doctors
A doctor's role not only includes patient care but also to provide evidence in the court as and when called upon to do so. Evidence giving in the court leads to an additional burden on the doctor with regards to the time and money spent on travelling, cancellation of the hearing after reaching the court, etc. An alternative for all these problems can be tele-evidence. This study aims to know the attitude and perception of final year undergraduate law students towards tele-evidence facilities for doctors. A cross sectional study was done using a questionnaire-based survey. The Likert scale questionnaire was used to assess the attitude, and the Cronbach alpha coefficient checked the Likert items' internal consistency. The analysis of the data was done using SPSS version 25. When summarised by median and mode for the individual Likert items, the results showed that the final year undergraduate law students have a positive outlook towards tele-evidence facilities for doctors but lack exposure to such advances. A study taking into account the opinion of practising lawyers and judges, especially those who have done court hearings using tele-evidence facilities for doctors, needs to be done. 2024, Indian Academy of Forensic Medicine. All rights reserved. -
Structure and biological properties of exopolysaccharide isolated from Citrobacter freundii
This study aimed to investigate the molecular characterization, antioxidant activity in vitro, cytotoxicity study of an exopolysaccharide isolated from Citrobacter freundii. Firstly, the culture conditions were standardized by the Design of experiments (DoE) based approach, and the final yield of thecrude exopolysaccharide was optimized at 2568 169 mg L?1. One large fraction of exopolysaccharide was obtained from the culture filtrate by size exclusion chromatography and molecular characteristics were studied. A new mannose rich exopolysaccharide (Fraction-I) with average molecular weight ~ 1.34 105 Da was isolated. The sugar analysis showed the presence of mannose and glucose in a molar ratio of nearly 7:2 respectively. The structure of the repeating unit in the exopolysaccharide was determined through chemical and 1D/2D- NMR experiments as:[Formula presented] Finally, the antioxidant activity, and the cytotoxicity of the exopolysaccharide were investigated and the relationship with molecular properties was discussed as well. 2020 Elsevier B.V. -
Data encryption in public cloud using multi-phase encryption model
Cloud computing the most used word in the world of Information Technology, is creating huge differences in IT industry. Nowadays huge amount of data is being generated and the researchers are finding new ways of managing these data. Basically, the word cloud refers to a virtual database that stores huge data from various clients. There are three types of cloud public, private and hybrid. Public cloud is basically for general users where users can use cloud services free or by paying. Private cloud is for any particular organizations and hybrid one is basically combine of both. Cloud offers various kind of services such as IAAS, PAAS, SAAS where services like platform for running any application, accessing the huge storage, can use any application running under cloud are given. The cloud also has a disadvantage regarding the security for the data storage facility. Basically, the public cloud is prone to data modification, data hacking and thus the integrity and confidentiality of the data is being compromised. Here in our work the concern is to protect the data that will be stored in the public cloud by using the multi-phase encryption. The algorithm that we have proposed is a combination of Rail Fence cipher and Play Fair cipher. 2018 Snata Choudhury, Dr. Kirubanand V.B. -
Structural domination and coloring of some (P7,C7)-free graphs
We show that every connected induced subgraph of a graph G is dominated by an induced connected split graph if and only if G is C-free, where C is a set of six graphs which includes P7 and C7, and each containing an induced P5. A similar characterization is shown for the class of graphs which are dominated by an induced connected complete split graph. Motivated by these results, we study structural descriptions of some classes of (P7, C7)-free graphs. In particular, we give structural descriptions for the class of (P7, C7, C4, gem)-free graphs and for the class of (P7, C7, C4, diamond)-free graphs. Using these results, we show that every (P7, C7, C4, gem)-free graph G satisfies ?(G)?2?(G)?1, and that every (P7, C7, C4, diamond)-free graph H satisfies ?(H)?max{3,?(H)}. 2020 Elsevier B.V. -
Roxburgh was right: Aponogeton microphyllus and Aponogeton undulatus are distinct species
Aponogeton microphyllus, previously placed under the synonymy of A. undulatus, is recognized here as a distinct species based on morphology, chromosome number, and molecular phylogenetics (nuclear ribosomal internal transcribed (ITS) spacer region). Observations on the type and live specimens revealed morphological differences between the two species. Aponogeton microphyllus flowered regularly and set seeds. Aponogeton undulatus flowered rarely, did not set seeds, but showed formation of young plantlets on the inflorescence axis. Similarly, different chromosome numbers were recorded in Aponogeton microphyllus and the two forms of A. undulatus, viz., AF1 and AF2, whichoccurin distinct populations. Aponogeton microphyllus exhibited polysomaty with root-tip cells showing 2n=40, 42, and 44 chromosomes. The two forms of A. undulatus, AF1 and AF2, showed 2n=84 and 86 chromosomes, respectively. Based on the ITS data, both speciesoccupiedtwo separate clades. Plastid trnK intron region indicated a close relationship between both species. Our study suggests the need for comprehensive phylogenetic analyses of A. undulatus across its distribution range based on more advanced techniques such as high-throughput sequencing data to understand the A. undulatus species complex and to detect natural hybrids of this species. 2023, Indian Academy of Sciences. -
Quantifying the role of nanocarbon fillers on dielectric properties of poly(vinylidene fluoride) matrix
Development of polymers with excellent dielectric properties is a challenge for advanced electronic devices. Impregnating conducting fillers like carbon nanoparticles can enhance the dielectric constant, retaining low loss due to its compatibility and favorable polarization within the polymer matrix. The multifunctional characteristics of coal-derived nanocarbon can improve permittivity and facilitate large-scale production at a lower cost. The incorporation of coal-based nanocarbon in the polymer matrix and its dielectric response is seldom investigated. In this work, different ratios (10:90, 50:50, 90:10 by weight) of nanocarbon/PVDF composite are prepared via a simple solution casting technique. The dielectric measurements show that nanofillers addition significantly augments the dielectric constant value, which is ?3 times (50:50 composite) higher than pure PVDF. The uniform distribution of 50% filler within the polymer matrix impeded the seepage of charge at the interface and enhanced the permittivity via polarization of accumulated charges. The composite also exhibited balanced dielectric loss that is essential for energy storage applications. The Author(s) 2022. -
Flexible Nanogenerators Based on Enhanced Flexoelectricity in Mn3O4 Membranes
Atomically thin, few-layered membranes of oxides show unique physical and chemical properties compared to their bulk forms. Manganese oxide (Mn3O4) membranes are exfoliated from the naturally occurring mineral Hausmannite and used to make flexible, high-performance nanogenerators (NGs). An enhanced power density in the membrane NG is observed with the best-performing device showing a power density of 7.99mWm?2 compared to 1.04Wm?2 in bulk Mn3O4. A sensitivity of 108mVkPa?1 for applied forces <10N in the membrane NG is observed. The improved performance of these NGs is attributed to enhanced flexoelectric response in a few layers of Mn3O4. Using first-principles calculations, the flexoelectric coefficients of monolayer and bilayer Mn3O4 are found to be 50100 times larger than other 2D transition metal dichalcogenides (TMDCs). Using a model based on classical beam theory, an increasing activation of the bending mode with decreasing thickness of the oxide membranes is observed, which in turn leads to a large flexoelectric response. As a proof-of-concept, flexible NGs using exfoliated Mn3O4 membranes are made and used in self-powered paper-based devices. This research paves the way for the exploration of few-layered membranes of other centrosymmetric oxides for application as energy harvesters. 2023 Wiley-VCH GmbH. -
A study of pulsation & rotation in a sample of A-K type stars in the Kepler field
We present the results of time-series photometric analysis of 15106 A-K type stars observed by the Kepler space mission. We identified 513 new rotational variables and measured their starspot rotation periods as a function of spectral type and discuss the distribution of their amplitudes. We examined the well-established period-color relationship that applies to stars of spectral types F5-K for all of these rotational variables and, interestingly, found that a similar period-color relationship appears to extend to stars of spectral types A7 to early-F too. This result is not consistent with the very foundation of the period-color relationship. We have characterized 350 new non-radial pulsating variables such as A- and F-type candidate ? Scuti, ? Doradus and hybrid stars, which increases the known candidate non-radial pulsators in the Kepler field significantly, by ?20%. The relationship between two recently constructed observables, Energy and Efficiency, was also studied for the large sample of non-radial pulsators, which shows that the distribution in the logarithm of Energy (log (En)) can be used as a potential tool to distinguish between the non-radial pulsators, to some extent. Through visual inspection of the light curves and their corresponding frequency spectra, we found 23 new candidate red giant solar-like oscillators not previously reported in the literature. The basic physical parameters such as masses, radii and luminosities of these solar-like oscillators were also derived using asteroseismic relations. 2018, The Author(s).