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Congruent Feature Selection Method to Improve the Efficacy of Machine Learning-Based Classification in Medical Image Processing

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 357-384页

作者： Mohd Anjum Naoufel Kraiem Hong Min Ashit Kumar dutta Yousef Ibrahim Daradkeh Department of Computer Engineering Aligarh Muslim UniversityAligarh202002India College of Computer Science King Khalid UniversityAbha61413Saudi Arabia School of Computing Gachon UniversitySeongnam13120Republic of Korea Department of Computer Science and Information Systems College of Applied SciencesAlMaarefa UniversityRiyadh13713Saudi Arabia Department of Computer Engineering and Information College of Engineering in Wadi AlddawasirPrince Sattam bin Abdulaziz UniversityAl-Kharj16273Saudi Arabia

Machine learning(ML)is increasingly applied for medical image processing with appropriate learning *** applications include analyzing images of various organs,such as the brain,lung,eye,etc.,to identify specific flaws/diseases for *** primary concern of ML applications is the precise selection of flexible image features for pattern detection and region *** of the extracted image features are irrelevant and lead to an increase in computation ***,this article uses an analytical learning paradigm to design a Congruent Feature Selection Method to select the most relevant image *** process trains the learning paradigm using similarity and correlation-based features over different textural intensities and pixel *** similarity between the pixels over the various distribution patterns with high indexes is recommended for disease ***,the correlation based on intensity and distribution is analyzed to improve the feature selection ***,the more congruent pixels are sorted in the descending order of the selection,which identifies better regions than the ***,the learning paradigm is trained using intensity and region-based similarity to maximize the chances of ***,the probability of feature selection,regardless of the textures and medical image patterns,is *** process enhances the performance of ML applications for different medical image *** proposed method improves the accuracy,precision,and training rate by 13.19%,10.69%,and 11.06%,respectively,compared to other models for the selected *** mean error and selection time is also reduced by 12.56%and 13.56%,respectively,compared to the same models and dataset.

关键词： Computer vision feature selection machine learning region detection texture analysis image classification medical images

Structural,optical,electrical,and dielectric relaxation properties of rare earth containing sodium bismuth titanate Na_(0.5)Bi_(0.5)TiO_(3) perovskite:Effect of ionic radius

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Journal of Rare Earths 2024年第2期42卷 383-391,I0006页

作者： Rajdip Roy Abhigyan dutta Department of Physics The University of BurdwanBurdwan713104India

The main focus of this work is to study the effect of the ionic radius of different rare earth dopant cations RE^(3+)(RE=La,Sm,Dy,and Ho) on structural and various physical properties of sodium bismuth titanate(Na_(0.5)B_(0.5)TiO_(3),NBT) based perovskite *** X-ray diffraction data indicate the successful formation of the rhombohedral phase(space group R3c) of NBT nano perovskite incorporated with various rare earth ions in *** lattice parameters were found to increase linearly with the ionic radius of the dopant *** ionic radii and atomic mass of rare earth dopants appear to be essential factors in the grain growth of the prepared *** grain growth results in better crystallinity of the sample by reducing the microstrain with the increase of dopant ionic *** emission scanning electron microscopy and energy-dispersive X-ray spectra confirm the prepared compositions' phase purity and *** UV-Vis spectra reveal that La-doped NBT composition exhibits the lowest optical band gap,which unfolds the application of NBT-based perovskite as photoactive *** ac conductivity and complex impedance spectra unveil that the composition with the largest ionic radius,i.e.,La-doped NBT compound,exhibits the highest dc and bulk conductivity with the lowest activation *** frequency-dependent dielectric data follows Havriliak-Negami(HN) formalism and non-Debye type relaxation *** also indicate that La-doped NBT composition exhibits the highest dielectric strength ***,this study first elaborates that the increasing ionic radius of the rare earth dopant cation in the Bi-site of NBT perovskite improves its microstructural,optical,and electrical properties.

关键词： Rare earth doped NBT Microstructural analysis Optical band gap AC Conductivity Dielectric relaxation Rare earths

Five-equation and robust three-equation methods for solution verification of large eddy simulation

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Journal of Hydrodynamics 2018年第1期30卷 23-33页

作者： Rabijit dutta Tao Xing Department of Mechanical Engineering College of EngineeringUniversity of Idaho

This study evaluates the recently developed general framework for solution verification methods for large eddy simulation（LES） using implicitly filtered LES of periodic channel flows at friction Reynolds number of 395 on eight systematically refined *** seven-equation method shows that the coupling error based on Hypothesis I is much smaller as compared with the numerical and modeling errors and therefore can be neglected. The authors recommend five-equation method based on Hypothesis II, which shows a monotonic convergence behavior of the predicted numerical benchmark（S_C）, and provides realistic error estimates without the need of fixing the orders of accuracy for either numerical or modeling errors. Based on the results from seven-equation and five-equation methods, less expensive three and four-equation methods for practical LES applications were derived. It was found that the new three-equation method is robust as it can be applied to any convergence types and reasonably predict the error trends. It was also observed that the numerical and modeling errors usually have opposite signs, which suggests error cancellation play an essential role in LES. When Reynolds averaged Navier-Stokes（RANS） based error estimation method is applied, it shows significant error in the prediction of S_C on coarse meshes. However, it predicts reasonable S_C when the grids resolve at least 80% of the total turbulent kinetic energy.

关键词： Large eddy simulation(LES) OpenFOAM periodic channel flow solution verification

Nonlinear Structures in an Ion-Beam Plasmas Including Dust Impurities with Nonthermal Nonextensive Electrons

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Communications in Theoretical Physics 2017年第7期67卷 117-124页

作者： Debjit dutta Biswajit Sahu Department of Mathematics West Bengal State University Barasat Kolkata 700126 India

The properties of dust ion acoustic waves are investigated in an unmagnetized multicomponent plasma system consisting of ion beam, charged positive and negative ions, electrons obeying nonthermal-Tsallis distribution and stationary negatively charged dust grains by the conventional Sagdeev pseudopotential method, through which the condition for existence of several nonlinear structures is analyzed theoretically. The dispersion relation for electrostatic waves is derived and analyzed and an expression of the energy integral equation is obtaJned. It is reported here that our plasma model supports solitions, double layers and supersoliton solutions for certain range of parameters. Finally, the effects of different physical plasma parameters on these nonlinear structures are studied numerically. The present theory should be helpful in understanding the salient features of the electrostatic waves in space and in laboratory plasmas where two distinct groups of ions and non-Maxwellian distributed electrons are present.

关键词： multicomponent plasma dust ion acoustic waves solitons and supersolitons

Dark Energy Accretion onto Van der Waal's Black Hole

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Communications in Theoretical Physics 2019年第2期71卷 209-219页

作者： Sandip dutta Ritabrata Biswas Department of Mathematics The University of BurdwanGolapbag Academic ComplexBurdwan-713104Purba Bard-dhamanWest BengalIndia

We consider the most general static spherically symmetric black hole metric. The accretion of the fluid flow around the Van der Waal's black hole is investigated and we calculate the fluid's four-velocity, the critical point and the speed of sound during the accretion process. We also analyze the nature of the universe's density and the mass of the black hole during accretion of the fluid flow. The density of the fluid flow is also taken into account. We observe that the mass is related to redshift. We compare the accreting power of the Van der Waal's black hole with Schwarzschild black hole for different accreting fluid.

关键词： black hole physics thermodynamics accretion disc extended Chaplygin gas

Assessing compressive strengths of mortar and concrete from digital images by machine learning techniques

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Frontiers of Structural and Civil Engineering 2022年第3期16卷 347-358页

作者： Amit SHIULY Debabrata dutta Achintya MONDAL Civil Engineering Department Jadavpur UniversityJadavpur 700032India Civil Engineering Department Camellia School of Engineering and TechnologyBarasat 700124India

Compressive strength is the most important metric of concrete *** nondestructive and semi-destructive tests can be used to evaluate the compressive strength of *** the present study,a new image-based machine learning method is used to predict concrete compressive strength,including evaluation of six different *** include support-vector machine model and various deep convolutional neural network models,namely AlexNet,GoogleNet,VGG19,ResNet,and *** the present investigation,cement mortar samples were prepared using each of the cement:sand ratios of 1:3,1:4,and 1:5,and using the water:cement ratios of 0.35 and *** concrete was prepared using the cement:sand:coarse aggregate ratios of 1:5:10,1:3:6,1:2:4,1:1.5:3 and 1:1:2,using the water:cement ratio of 0.5 for all *** samples were cut,and several images of the cut surfaces were captured at various zoom levels using a digital *** samples were then tested destructively for compressive *** images and corresponding compressive strength were then used to train machine learning models to allow them to predict compressive strength based upon the image *** Inception-ResNet-V2 models exhibited the best predictions of compressive strength among the models ***,the present findings validated the use of machine learning models as an efficient means of estimating cement mortar and concrete compressive strengths based on digital microscopic images,as an alternative nondestructive/semi-destructive test method that could be applied at relatively less expense.

关键词： support vector machine deep convolutional neural network microscope digital image curing period

Plant diversity, population structure, and regeneration status in disturbed tropical forests in Assam, northeast India

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Journal of Forestry Research 2013年第4期24卷 715-720页

作者： Gitamani dutta Ashalata Devi Department of Environmental Science Tezpur University

We investigated the plant population structure and the phy- tosociological and regeneration status in two disturbed tropical forests in Assam Province, the Hojai Reserve Forest and Kumorakata Reserve Forest. A total of 166 species （80 trees, 20 shrubs and 66 herbs） of 136 genera and 63 families were recorded in both study sites. The disturbance index at the two sites, Kumorakata Reserve Forest and Hojai Reserve Forest, were recorded at 11.4% and 3.70% respectively. Reverse J-shaped population curve and exploitation of tree species in higher girth classes were recorded at both study sites. In the girth classes （10-30 cm, 30-60 cm, 60-90 cm and 90-120 cm in size） the percentage of cut stump density was higher than the percentage of individual living trees. The 18% （Kumorakata Reserve Forest） and 7% （Hojai Reserve Forest） spe- cies were recorded as not regenerating. Illegal felling and over-exploitation of forest resources may lead to species-specific changes in the population structure and can alter the future structure and composi- tion of the forests.

关键词： plant diversity regeneration disturbance population struc-ture Assam India

Estimating statistics of sky brightness using radio interferometric observations

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Research in Astronomy and Astrophysics 2019年第4期19卷 119-136页

作者： Prasun dutta Meera Nandakumar Department of Physics IIT (BHU) Varanasi

Radio interferometers are used to construct high resolution images of the sky at radio frequencies and are the key instruments for accessing the statistical properties of the evolution of neutral hydrogen over cosmic time. Here we use simulated observations of the model sky to assess the efficacy of different estimators of the large-scale structure and power spectrum of the sky brightness distribution. We find that while the large-scale distribution can be reasonably estimated using the reconstructed image from interferometric data, estimates of the power spectrum of the intensity fluctuations calculated from the image are generally biased. This bias is found to be more pronounced for diffuse emission. The visibility based power spectrum estimator, however, gives an unbiased estimate of the true power spectrum. This work demonstrates that for an observation with diffuse emission the reconstructed image can be used to estimate the large-scale distribution of the intensity, while to estimate the power spectrum, visibility based methods should be *** the upcoming experiments aimed at measuring the evolution of the power spectrum of the neutral hydrogen distribution, this is a very important result.

关键词： instrumentation:interferometers methods:data analysis techniques:interferometric

Analysis of the electrical characteristics of GaInP/GaAs HBTs including the recombination effect

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Journal of Semiconductors 2012年第5期33卷 38-43页

作者： Gourab dutta Sukla Basu Indian Institute of Technology Kharagpur ECE Department Kalyani Government Engineering College

An analytical model is used to predict the effects of surface recombination current on the gain and transit time of GalnP/GaAs heterojunction bipolar transistors（HBTs）.The present analysis shows that consideration of the recombination current gives current gain values that are comparable to those of the experimental *** dependence of current gain on temperature,base doping and emitter area are also analyzed,and the variation in collector current with emitter-base voltage,temperature and doping is considered.

关键词： GaInP/GaAs HBT current gain transit time recombination current surface recombination ideality factor