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Improved dragonfly optimizer for intrusion detection using deep clustering CNN-PSO classifier
With the rapid growth of internet based services and the data generated on these services are attracted by the attackers to intrude the networking services and information. Based on the characteristics of these intruders, many researchers attempted to aim to detect the intrusion with the help of automating process. Since, the large volume of data is generated and transferred through network, the security and performance are remained an issue. IDS (Intrusion Detection System) was developed to detect and prevent the intruders and secure the network systems. The performance and loss are still an issue because of the features space grows while detecting the intruders. In this paper, deep clustering based CNN have been used to detect the intruders with the help of Meta heuristic algorithms for feature selection and preprocessing. The proposed system includes three phases such as preprocessing, feature selection and classification. In the first phase, KDD dataset is preprocessed by using Binning normalization and Eigen-PCA based discretization method. In second phase, feature selection is performed by using Information Gain based Dragonfly Optimizer (IGDFO). Finally, Deep clustering based Convolutional Neural Network (CCNN) classifier optimized with Particle Swarm Optimization (PSO) identifies intrusion attacks efficiently. The clustering loss and network loss can be reduced with the optimization algorithm. We evaluate the proposed IDS model with the NSL-KDD dataset in terms of evaluation metrics. The experimental results show that proposed system achieves better performance compared with the existing system in terms of accuracy, precision, recall, f-measure and false detection rate. 2022 Tech Science Press. All rights reserved. -
Facile synthesis of novel antimony selenide nanocrystals with hierarchical architecture by physical vapor deposition technique
Stoichiometric antimony selenide (Sb 2 Se 3 ) nanocrystals have been successfully engineered by a facile physical vapor deposition method, employing a single precursor of polycrystalline Sb 2 Se 3 charge in a closed quartz ampoule under high vacuum without any foreign seed or extraneous chemical elements. This work underscores the efficacy of the vapor deposition process and provides synthetic strategies to scale down bulk Sb 2 Se 3 into novel nanostructures. The morphological evolution of the tailored architecture was examined on micro and nano size scales by scanning electron microscopy and high-resolution transmission electron microscopy. The intrinsic mechanism governing the nanostructure formation is revealed as layer-by-layer growth, related to the unique layered structure of Sb 2 Se 3 . The optical properties of the grown crystals were probed by UVvisNIR and photoluminescence tools. The band-gap values of the microfibers, nanorods, nanooctahedra and nanospheres estimated from UVvisNIR analysis are found to be 1.25, 1.47, 1.51 and 1.75 eV, respectively. Powder X-ray diffraction, energy-dispersive analysis by X-rays, X-ray photoelectron spectroscopy, Raman spectroscopy and photoluminescence studies confirmed the quality, phase purity and homogeneity of the as-grown nanostructures. The adopted physical vapor deposition method is thus shown to be a simple and elegant route which resulted in the enhancement of the band gap for the Sb 2 Se 3 samples compared with their counterparts grown by chemical methods. This approach has great potential for further applications in optoelectronics. International Union of Crystallography, 2019 -
Physical vapor deposition and enhancement of optoelectronic properties of SnSe2 platelets
Stoichiometric tin diselenide (SnSe2) platelet crystals have been prepared by physical vapor deposition (PVD) method under high vacuum (~ 106mbar) using a homemade dual-zone furnace. The driving force for growth was optimized in terms of temperature difference (?T = 270 to 420C) of nutrient and growth zones. Good quality platelets, devoid of any screw dislocations, hillocks, defects etc. were crystallized at ?T = 400C by layer growth mode as per the 3D optical profiler and electron microscopic images. Rietveld refinement of the PXRD data using FullProf suite software justified hexagonal crystal structure with a = 3.811 c = 6.137and the computed density (5.967g/cm3) is in agreement with that obtained based on Archimedes principle. Chemical homogeneity of these samples was probed by EDAX, XPS and Raman analysis. The thermal and mechanical behavior was investigated by TGA as well as Vickers microhardness experiments. The values of optical band gap (1.20eV), absorption coefficient (7.25 105cm?1), resistivity (2.70 ? cm), mobility (32.70 cm2V?1s?1) and carrier concentration (3.08 1016cm?3) have been evaluated using UVVis-NIR, photoluminescence, and Hall effect measurements. The enhancement of optoelectronic parameters of the as-grown SnSe2 platelets free of polytypism, throws light on their potential for photovoltaic applications. 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
Vapor growth and optimization of supersaturation for tailoring the physical properties of stoichiometric Sb2Se3 crystalline habits
The evolution of different morphologies (fibers, whiskers, needles, and spherulites) of antimony selenide (Sb2Se3), devoid of foreign chemical elements, was explored by the physical vapor deposition (PVD) method, employing an indigenously assembled tubular furnace, which showed layer growth mode as per the metallurgical and scanning electron micrographs. Supersaturation for crystallization was optimized by precisely controlling the difference in temperatures of nutrient and growth zones, ?T = TN ? TG, where ?T = 125 to 350C. The strain and dislocation density of the crystals were evaluated from the crystallographic data. Monophase nature has been confirmed by Rietveld refinement analysis of the PXRD findings, using Full Proof software. UVVis-NIR and PL spectra of the morphologies revealed band gap, Eg in the range, 1.151.18eV. Among these habits, good-quality whiskers bearing flat faces of appreciable crystallinity, stoichiometry, thermal stability and mechanical strength were produced due to the periodic deposition of atoms associated with the progression of smooth vaporsolid (v?) interface as evident from PXRD, EDAX, XPS, TGA and microindentation analyses. Hall effect measurements resulted in obtaining appreciable values of electrical parameters, ? = 145.36 ? cm and n = 7.39 1018cm?3 for PV applications. Moreover, optical studies justified direct transition with adequate photon absorption which promises the suitability of whiskers as absorbers in the energy conversion process. 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
Comprehensive Review on CdTe Crystals: Growth, Properties, and Photovoltaic Application
Abstract: Despite the deep interest of materials scientists in cadmium telluride (CdTe) crystal growth, there is no single source to which the researchers can turn towards for comprehensive knowledge of CdTe compound semiconductor synthesis protocols, physical properties and performance. Considering this, the present review work focuses to bridge this shortcoming. The direct band gap (Eg) CdTe crystals have been in limelight in photovoltaic application (PV) since the optoelectronic properties such as Eg (1.49 eV), absorption coefficient (~105 cm1), p-type conductivity, carrier concentration (6 1016 cm3) and mobility (1040 cm2/(V s)) at the room temperature are reported that optimum for solar cells. Additionally, Cd-based compounds such as CdTe and CdZnTe have also been widely studied in the field of ? and ?-ray radiation detector, because of their extraordinary advantages like large atomic number, low weight, high mechanical hardness, flexibility, and the availability of the constituent materials. CdTe has demerits like toxicity and high melting temperature, which will complicate the growth of stoichiometric cadmium telluride crystals at high temperatures. In this regard, the review work focused the periodic evolution of the growth protocols until now. The different synthesis methods, characterization, and recent progress in the field of crystalline CdTe were discussed briefly. Important optical and electrical characteristics are presented in the tables and remaining issues have discussed, this could be looked into for further research. The applications of CdTe crystals for photovoltaic fields are also discussed in this review paper. Pleiades Publishing, Ltd. 2023. ISSN 0031-918X, Physics of Metals and Metallography, 2023, Vol. 124, No. 14, pp. 17951812. Pleiades Publishing, Ltd., 2023. ISSN 0031-918X, Physics of Metals and Metallography, 2023. Pleiades Publishing, Ltd., 2023. -
Forensic applications of graphene oxide
Forensic analysis is an enormous field comprising the detection of various types of samples. The objective of forensic evidence examination is to provide a cohesive, transparent, and unbiased judgment of the evidence's significance to the investigators. Graphene oxide (GO) is an abundant substance that comprises carbon, hydrogen, and oxygen in a single layer making it highly economical. Therefore, the utilization of GO is highly considered for achieving the detection and analysis of various substrates. This can be justified by its facile and economical preparation that contributes to improving its significance and applicability. Forensic samples include trace elements that can be pre-concentrated with the help of a sustainable medium provided by GO. This book chapter aims to provide exciting insights into the synthesis, properties, and applications of GO in the detection of various forensic samples of GO. 2024 -
Experimental investigation of a biomass-derived nanofluid with enhanced thermal conductivity as a green, sustainable heat-transfer medium and qualitative comparison via mathematical modelling
In this study, bio-based carbon nanospheres (CNSs) were synthesized from lignocellulosic-rich groundnut skin (Arachis hypogaea) and tested for their practical application in nanofluids (NFs) for enhanced heat transfer. The CNSs were characterized using various techniques, including FESEM, EDS, XRD, Raman spectroscopy, zeta potential analysis, and FTIR. Thermal conductivity (TC) and viscosity measurements were conducted using transient plane source (TPS) technique with a Hot Disk thermal analyser and discovery hybrid rheometer, respectively. The nanoparticles (NPs) were dispersed in two base fluids: ethylene glycol (EG) and a 60 : 40 mixture of deionized water (DI) and EG. Optimization studies were performed by varying the stirring and measurement times to improve TC values. The results showed that when a power source of 40 mW was applied at a high concentration of nanoparticles (i.e., 0.1 wt%), there was a 91.9% increment in thermal conductivity (TC) compared to the base fluid EG. DI-EG-based nanofluids (NFs) exhibited enhancements of up to 45% compared to the base fluid DI-EG (60 : 40), with a heating power of 80 mW and concentration of 0.1 wt%. These results demonstrated significant TC improvements with NP incorporation. Further experiments were performed by varying the temperature in the range of 30-80 C with readings taken for every 10 C increase, which showed a direct relation with the TC values. At 80 C, EG-based NFs showed increments of 77%, 111.49%, 139.67% and 175% at 0.01, 0.02, 0.05 and 0.1 wt% concentrations of NPs, respectively. It was also found that with the increase in the concentration of NPs, viscosity increased, whereas an increase in the temperature led to a decrease in viscosity. The CNS nanofluid exhibited a Newtonian behaviour with the nanoparticle concentration and temperature, resulting in an approximately 114% enhancement compared to the base fluid when the concentration of CNSs was 0.1 wt% at 30 C but decreased by up to 18% when the temperature was increased to 90 C. Using appropriate mathematical models for assessing thermophysical quantities, it was discovered that the model values and experimental values correspond reasonably well. Our method thus validates our experimental results and deepens the understanding of the mechanisms behind enhancing thermal conductivity in biomass-derived nanofluids. In summary, our work advances sustainable nanomaterial synthesis, providing a new solution for boosting thermal conductivity while maintaining environmental integrity, thereby inspiring further research and innovation in this field. 2024 RSC. -
A hybrid level set based approach for surface water delineation using landsat-8 multispectral images
The detection and delineation of surface water is a crucial step in change detection studies on water bodies using satellite images. Single band methods, spectral index methods, classification using machine learning and spectral un-mixing methods are the widely used strategies for surface water mapping from multi-spectral images. Level set theory based algorithms have been successfully employed in image segmentation problems and are proven to be effective. This study presents a hybrid level set theory based segmentation algorithm which is a combination of edge based and region based approaches to detect and delineate surface water bodies in Landsat 8 images. Level set algorithms were applied in combination with Modified Normalized Difference Water Index (MNDWI) to further improve the delineation accuracy. Robustness of the proposed approach was established by successfully applying the algorithm to delineate water bodies of different sizes, ranging from 0.5 km2 to 298 km2 in surface area. The proposed algorithm was also compared with established machine learning based delineation methods and found to be faster than the algorithms those produced comparable delineation outputs. As the ground truth was not available for accuracy measurement, the output image of the proposed method was compared with the outputs of the machine learning algorithms using Pearsons correlation co-efficient, Structural Similarity Index (SSIM) and Dice Similarity Index. The proposed algorithm was subsequently applied to multi-temporal Landsat data for water body change detection and analysis. 2021, International Association of Engineers. All rights reserved. -
Surface water detection and delineation using remote sensing images: a review of methods and algorithms
Multispectral and hyperspectral images captured by remote sensing satellites or airborne sensors contain abundant information that can be used to study and analyze objects of interest on the surface of earth and their properties. The potential of remotely sensed images for studying natural resources like water has been studied by researchers over the past many years. As water is an important natural resource that needs to be conserved, such studies have been of great interest to the scientific community. By employing appropriate digital image processing techniques on images taken from remote sensing satellites or airborne sensors, an effective system can be developed to study the quantitative and qualitative changes happening to surface water bodies over a period of time. Surface water detection and mapping is a crucial and necessary step in such studies and different automated and semi-automated methods have been developed over the years for mapping water in remotely sensed images. Remote sensing sensors capture images at multiple bands corresponding to different wavelength ranges in the EM spectrum. Digital image processing based techniques for water mapping falls predominantly into four categories; (i) single band based methods, (ii) spectral index based methods, (iii) machine learning based methods and (iv) spectral mixture analysis based methods. This paper presents a review of techniques, methods, algorithms and the sensors/satellites that have been developed and experimented with to perform surface water body detection and delineation from remote sensing images. 2020, Springer Nature Switzerland AG. -
Evaluation of machine learning algorithms for surface water delineation using landsat 8 images
Surface water detection and delineation is an important and necessary step in change detection studies on water bodies using multispectral images. Commonly used techniques for surface water delineation from multispectral images are single band density slicing, spectral index based, machine learning based classification and spectral un mixing based methods. This paper presents a comparative study of commonly used machine learning algorithms viz. ANN, SVM, Decision Tree, Random Forest and K-means clustering for their suitability and effectiveness when applied on Landsat 8 images for surface water detection and delineation. The algorithms are compared for their classification accuracy and execution time. While all the above mentioned algorithms exhibited their usefulness in water detection, Decision Tree and Random Forest algorithms were found be faster in both training phase and testing phase and also yielded better accuracy with fewer miss-classifications. Though K-means clustering with more than four clusters yielded results comparable to that of supervised classification methods, it requires appropriate post-processing to obtain the output image with only two clusters; corresponding to water pixels and non-water pixels. Pierson's correlation co-efficient and Structural similarity Index (SSIM) are computed to compare the correlation and similarity of the output images yielded by the algorithms being studied. 2020, Institute of Advanced Scientific Research, Inc. All rights reserved. -
Enzyme immobilization on biomass-derived carbon materials as a sustainable approach towards environmental applications
Enzymes with their environment-friendly nature and versatility have become highly important green tools with a wide range of applications. Enzyme immobilization has further increased the utility and efficiency of these enzymes by improving their stability, reusability, and recyclability. Biomass-derived matrices when used for enzyme immobilization offer a sustainable solution to environmental pollution and fuel depletion at low costs. Biochar and other biomass-derived carbon materials obtained are suitable for the immobilization of enzymes through different immobilization strategies. Environmental pollution has become an utmost topic of research interest due to an ever-increasing trend being observed in anthropogenic activities. This has widely contributed to the release of various toxic effluents into the environment in their native or metabolized forms. Therefore, more focus is being directed toward the utilization of immobilized enzymes in the bioremediation of water and soil, biofuel production, and other environmental applications. In this review, up-to-date literature concerning the immobilization and potential uses of enzymes immobilized on biomass-derived carbon materials has been presented. 2022 Elsevier Ltd -
Social capital in the form of self-help groups in India: a powerful resilient solution to reduce household financial vulnerability
Due to the COVID-19 pandemic and the economys general situation, many households are now financially vulnerable. It is like a vicious cycle: once a household is caught, it will remain in the trap until and unless it competently manages its finances. These problems experienced by households have drawn attention to social capital. Self-help groups (SHGs) originated in India to pull out low-income households from poverty and are now recognized as social capital, which can be defined as the action of a group cooperating to enhance all its members benefits. This article aims to explain how SHGs have contributed to reducing various factors or determinants of household financial vulnerability through a review of several other publications, theses, newspaper articles, and reports. It was discovered that SHGs now provide much more benefits than just alleviating poverty. They have helped to reduce bad loans or non-performing assets, reduced the dependence on informal sources of finance, made households more resilient toward crises such as COVID-19, and enabled households to save money and manage their finances accurately. Organizing themselves into SHGs is the only way for rural households to overcome financial difficulties. 2023 Taylor & Francis Group, LLC. -
Counselling and psychological wellbeing of people living with HIV in Kerala
There is a dearth in the documentation of the benefits of HIV-counseiling in India. This article deals with how HIV-counselling facilitates the psychological wellbeing of Persons Living with HIV (PLHIV) in Kerala, India. About 269 PLHIV participated in the study. Meaning in Life Questionnaire, Illness Perception Questionnaire and Psychological Wellbeing Scale were used. It was noticed that counselling did not impact the scores on subscales such as Timeline, Emotional Representation and Consequences, while the scores on Self-Acceptance and Autonomy did not differ even with counselling. Findings call for a reconsideration of the way HIV-counselling is provided. -
Understanding stigma and burnout among HIV/ AIDS health care workers Implications for counselling
The article examines the association between burnout and stigma among Health Care Workers (HCWs) and highlights the need for counselling services in the care of the HCWs. Stereotypes of HIV/AIDS and burnout in HCWs caring for people living with HIV/AIDS (PLHIV) were assessed using self-report methods. Stereotypes about AIDS Scale (SAAS) and Maslach Burnout Inventory MBI were completed by 120 staff from 8 community care centres for PLHIV across south India. Results of SAAS showed that about 33 percent respondents manifested high level of stigma while 35 percent exhibited moderate levels. The results of MBI showed high level of burnout in about 31 percent and moderate in 35 percent respondents. -
A multilevel analysis of hiv1-miR-H1 miRNA using KPCA, K-means, Random Forest and online target tools
The goal of this study was to propose a workflow using machine learning to identify and predict the miRNA targets of Human Immunodeficiency virus 1. miRNAs which is ~21 nt long are attained from larger hairpin RNA precursors and is maintained in the secondary structure of their precursor relatively than in primary chain of successions. The proposition approach for identification and prediction of miRNA targets in hiv1-miR-H1is based on secondary structure and E-value through machine learning. Data Linearity of Length and e-value for sequence match with hiv1-mir-H1 is verified using Kernel PCA. miRNA targets were grouped into clusters thereby indicating similar targets using K-means algorithm. Classification model using Random Forest was implemented regards to each secondary features variable considering feature relevance. A learning methodology is put forward that assimilate and integrate the score returned by various machine learning algorithms to predict cellular hiv1-miR-H1 targets. Gene targets results using TargetScan, miRanda, PITA, DIANA microT and RNAhybrid are also explored for multiple parameters. 2021 Inderscience Enterprises Ltd. -
Escape velocity backed avalanche predictor neural evidence from nifty /
International Journal of Recent Technology And Engineering, Vol.8, Issue 4, pp.486-490, ISSN No: 2277-3878. -
Multifractal analysis of volatility for detection of herding and bubble: evidence from CNX Nifty HFT /
Investment Management And Financial Innovations, Vol.16, Issue 3, pp.182-193 -
Power law in tails of bourse volatility – evidence from India /
Investment Management And Financial Innovations, Vol.16, Issue 1, pp.291-298 -
Medical Tourism in South India - A Relative Study of the Principal participants in hospital and hospitality industry in South India
International Journal of Management, IT and Engineering Vol.3, ISSUE 1, pp. 613-626 ISSN No. 2249-0558 -
A literature review on destination management organization /
Zenith International Journal of Multidisciplinary Research, Vol.4, Issue 12, pp.675-681, ISSN No: 2231-5780.