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On dry machining of AZ31B magnesium alloy using textured cutting tool inserts

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Journal of Magnesium and Alloys 2024年第4期12卷 1608-1618页

作者： Shailendra Pawanr Kapil gupta Department of Mechanical and Industrial Engineering Technology University of JohannesburgDoornfontein CampusJohannesburg 2028 South Africa

Magnesium alloys have many advantages as lightweight materials for engineering applications,especially in the fields of automotive and *** undergo extensive cutting or machining while making products out of *** cutting,a sustainable machining method,causes more friction and adhesion at the tool-chip *** of the promising solutions to this problem is cutting tool surface texturing,which can reduce tool wear and friction in dry cutting and improve machining *** paper aims to investigate the impact of dimple textures(made on the flank face of cutting inserts)on tool wear and chip morphology in the dry machining of AZ31B magnesium *** results show that the cutting speed was the most significant factor affecting tool flank wear,followed by feed rate and cutting *** tool wear mechanism was examined using scanning electron microscope(SEM)images and energy dispersive X-ray spectroscopy(EDS)analysis reports,which showed that at low cutting speed,the main wear mechanism was abrasion,while at high speed,it was *** chips are discontinuous at low cutting speeds,while continuous at high cutting *** dimple textured flank face cutting tools facilitate the dry machining of AZ31B magnesium alloy and contribute to ecological benefits.

关键词： Magnesium alloy Dry machining Textured tools Flank wear Sustainability

Direct scaling of residual displacements for bilinear and pinching oscillators

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 129-149页

作者： Mohammad Saifullah Vinay K.gupta Department of Civil Engineering Indian Institute of Technology KanpurKanpur 208016India

The estimation of residual displacements in a structure due to an anticipated earthquake event has increasingly become an important component of performance-based earthquake engineering because controlling these displacements plays an important role in ensuring cost-feasible or cost-effective repairs in a damaged structure after the *** attempt is made in this study to obtain statistical estimates of constant-ductility residual displacement spectra for bilinear and pinching oscillators with 5%initial damping,directly in terms of easily available seismological,site,and model *** of the available models for the bilinear and pinching oscillators are useful when design spectra for a seismic hazard at a site are not *** statistical estimates of a residual displacement spectrum are proposed in terms of earthquake magnitude,epicentral distance,site geology parameter,and three model parameters for a given set of ductility demand and a hysteretic energy capacity coefficient in the case of bilinear and pinching models,as well as for a given set of pinching parameters for displacement and strength at the breakpoint in the case of pinching model *** proposed scaling model is applicable to horizontal ground motions in the western *** earthquake magnitudes less than 7 or epicentral distances greater than 20 km.

关键词： residual displacement spectrum bilinear hysteresis model pinching hysteresis model nonlinear analysis scaling model

Optimizing calcination of coal by-products for maximizing REE leaching recovery and minimizing Al,Ca,and Fe contamination

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Journal of Rare Earths 2024年第7期42卷 1354-1365,I0006页

作者： Tushar gupta Ahmad Nawab Rick Honaker MP Materials Mountain Pass Mine 67750 Bailey RoadMountain PassCA92366USA Department of Mining Engineering University of KentuckyLexingtonKY40506USA

High-temperature calcination is effective in improving the leaching characteristics of rare earth elements(REEs)from conventional REE-bearing minerals by transforming them into more leachable ***,the recovery of contaminants such as Al,Fe,and Ca also increases *** objective of the study was to maximize the REE extraction while minimizing the concentration of contaminant ions(Al,Ca,and Fe)in the leach *** density fractions of the coarse refuse from the Baker and Fire Clay seam coal refuse were pulverized to a top size of 180μm and used as a feedstock for the *** the samples generated from thermal treatment were leached at 1%(w/v)using 1.2 mol/L sulfuric acid at 75℃ for 2 *** results from a parametric program based on a Box-Behnken design were used for modeling and optimization of three operating parameters associated with the lab-scale calcination *** parameters included temperature(400-800℃),ramp rate(2-10℃/min)and holding time(0-120 min).It was determined that the calcination temperature was the most significant parameter influencing REE *** majority of the heavy rare earth elements(HREEs)were found to be present in an insoluble form in the calcination products and were marginally affected by thermal treatment.A strong correlation between light rare earth elements recovery(LREEs)and Al suggested a possible association with *** optimum operating conditions for high REE recovery with comparatively lower contaminant concentration for 1.6 specific gravity float and 2.2 sink fractions of Baker and Fire Clay seam material were determined to be at 776,800℃ and 407,800℃,calcining temperatures,respectively.A higher optimum temperature of 1.6 float fraction of Baker seam relative to Fire Clay seam material was due to elevated pyrite concentration in Baker seam *** treatment at 400℃ converted pyrite into a soluble intermedium iron oxide,resulting in a high Fe content in the ***

关键词： Calcination Optimization Rare earth elements Coal refuse

Optimal design of hybrid renewable-energy microgrid system:a techno-economic-environment-social-reliability perspective

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Clean Energy 2024年第1期8卷 66-83页

作者： Manoj gupta Annapurna Bhargava Electrical Engineering Department Rajasthan Technical UniversityKotaRajasthan 324010India Electrical and Electronics Engineering Department IPS Academy Institute of Engineering and Science IndoreMadhya Pradesh 452012India

The main objective of this paper is to select the optimal model of a hybrid renewable-energy microgrid(MG)system for a village in *** MG comprises solar photovoltaic(PV)modules,a wind turbine generator,a biomass generator,a battery bank,a diesel generator and an electric *** optimal model selection is based on technical,economic,environmental,social and reliability parameters.A novel spoonbill swarm optimization algorithm is proposed to select the best hybrid MG *** optimization results are compared with particle swarm optimization,the genetic algorithm and the grasshopper optimization *** number or size of components of the optimized MG system is 215 PV modules,92 kW of wind turbine generation,25 kW of biomass generation,267 batteries,22 kW of electric vehicles and 30 kW of diesel *** optimized system was selected based on technical factors such as renewable dispersion(93.5%),the duty factor(5.85)and excess energy(15975 kWh/year)as well as eco-nomic considerations including the net present cost(Rs.34686622)and the cost of energy(9.3 Rs./kWh).Furthermore,environ-mental factors such as carbon emissions(396348 kg/year)and atmospheric particulate matter(22.686 kg/year);social factors such as the human progress index(0.68411),the employment generation factor(0.0389)and local employment generation(15.64643);and reliability parameters including loss of power supply probability(0.01%)and availability index(99.99%)were considered during the selection *** spoonbill swarm optimization algorithm has reduced the convergence time by 1.2 times and decreased the number of iterations by 0.83 times compared with other *** performance of the MG system is validated in the MATLAB®*** results show that the MG system is the optimal system considering technical,economic,environmental,social and reliability ***,the spoonbill swarm optimization algorithm is found to be more efficient than the other

关键词： cost of electricity microgrid reliability spoonbill techno-economic

Operator Equations Inducing Some Generalizations of Slant Hankel Operators

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Acta Mathematica Sinica,English Series 2024年第8期40卷 2017-2036页

作者： Gopal DATT Bhawna Bansal gupta Department of Mathematics PGDAV CollegeUniversity of DelhiNew Delhi-110065India Department of Mathematics Miranda HouseUniversity of DelhiDelhi-110007India

An extension of slant Hankel operator,namely,the kth-orderλ-slant Hankel operator on the Lebesgue space L^(2)(T^(n)),where T is the unit circle and n≥1,a natural number,is described in terms of the solution of a system of operator equations,which is subsequently expressed in terms of the product of a slant Hankel operator and a unitary *** study is further lifted in Calkin algebra in terms of essentially kth-orderλ-slant Hankel operators on L^(2)(T^(n)).

关键词： Hankel operator Lebesgue space of n-dimensional torus kth-order slant Hankel operator essentially kth-orderλ-slant Hankel operator

Multi-head neural networks for simulating particle breakage dynamics

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 130-141页

作者： Abhishek gupta Barada Kanta Mishra School of Mechanical Sciences Indian Institute of Technology(IIT)GoaPonda 403401India School of Chemical and Materials Science Indian Institute of Technology(IIT)GoaPonda 403401India

The breakage of brittle particulate materials into smaller particles under compressive or impact loads can be modelled as an instantiation of the population balance integro-differential *** this paper,the emerging computational science paradigm of physics-informed neural networks is studied for the first time for solving both linear and nonlinear variants of the governing *** conventional methods,the proposed neural network provides rapid simulations of arbitrarily high resolution in particle size,predicting values on arbitrarily fine grids without the need for model *** network is assigned a simple multi-head architecture tailored to uphold monotonicity of the modelled cumulative distribution function over particle *** method is theoretically analyzed and validated against analytical results before being applied to real-world data of a batch grinding *** agreement between laboratory data and numerical simulation encourages the use of physics-informed neural nets for optimal planning and control of industrial comminution processes.

关键词： Particle breakage dynamics Population balance equation Physics-informed neural networks

Trigonometric tension B-spline collocation approximations for time fractional Burgers’equation

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Journal of Ocean Engineering and Science 2024年第5期9卷 508-516页

作者： Brajesh Kumar Singh Mukesh gupta School of Physical and Decision Sciences Department of MathematicsBabasaheb Bhimrao Ambedkar University Lucknow 226025(UP)INDIA

This manuscript’s aim is to form and examine the numerical simulation of Caputo-time fractional nonlinear Burgers’equation via collocation approach with trigonometric tension B-splines as base ***,L 1 discretization formula is utilized for the time fractional derivative and after linearizing the nonlinear term,the trigonometric tension B-spline interpolants are utilized to get a system of simultaneous linear equations that are solved via Gauss elimination ***,numerical approximation at the desired time level is *** is demonstrated via von-Neumann approach that proposed scheme produces stable *** results of six different test examples having their analytical solutions are compared with the results in the literature to validate the accuracy and efficiency of the scheme.

关键词： Fractional Burgers’equation Trigonometric tension B-spline Collocation scheme Gauss elimination method

Prediabetes in children and adolescents:A ticking bomb!

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World Journal of Clinical Pediatrics 2024年第2期13卷 11-15页

作者： Anju gupta Nitin Choudhary Nishkarsh gupta Department of Anesthesiology Pain Medicine and Critical CareAll India Institute of Medical ScienceNew Delhi 110076India Department of Onco-Anesthesiology and Palliative Medicine All India Institute of Medical ScienceNew Delhi 110029India

Prediabetes in children and adolescents is on the rise which has drawn significant attention over the past *** is an early warning sign of the underlying pathophysiological changes which in due course of time might compound into type II diabetes *** incidence of prediabetes in adolescents ranges from 4%-23%which is alarmingly high and requires active intervention from the *** have discussed early identification of high-risk patients,prompt screening and active intervention to manage this growing problem.

关键词： Prediabetes Children Adolescents Glucose metabolism Complications

Covalent Bond Based Android Malware Detection Using Permission and System Call Pairs

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Computers, Materials & Continua 2024年第3期78卷 4283-4301页

作者： Rahul gupta Kapil Sharma R.K.Garg Department of Information Technology Delhi Technological UniversityNew Delhi110042India Department of Mechanical Engineering Deenbandhu Chhotu Ram University of Science and TechnologyMurthal131039India

The prevalence of smartphones is deeply embedded in modern society,impacting various aspects of our *** versatility and functionalities have fundamentally changed how we communicate,work,seek entertainment,and access *** the many smartphones available,those operating on the Android platform dominate,being the most widely used *** widespread adoption of the Android OS has significantly contributed to increased malware attacks targeting the Android ecosystem in recent ***,there is an urgent need to develop new methods for detecting Android *** literature contains numerous works related to Android malware *** far as our understanding extends,we are the first ones to identify dangerous combinations of permissions and system calls to uncover malicious behavior in Android *** introduce a novel methodology that pairs permissions and system calls to distinguish between benign and malicious *** approach combines the advantages of static and dynamic analysis,offering a more comprehensive understanding of an application’s *** establish covalent bonds between permissions and system calls to assess their combined *** introduce a novel technique to determine these pairs’Covalent Bond Strength *** pair is assigned two scores,one for malicious behavior and another for benign *** scores serve as the basis for classifying applications as benign or *** correlating permissions with system calls,the study enables a detailed examination of how an app utilizes its requested permissions,aiding in differentiating legitimate and potentially harmful *** comprehensive analysis provides a robust framework for Android malware detection,marking a significant contribution to the *** results of our experiments demonstrate a remarkable overall accuracy of 97.5%,surpassing various state-of-the-art detection techniques proposed in the current literature.

关键词： Android malware android security hybrid analysis permission and system call pairs