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Linear feedback-based control of blood glucose in a modified model for glucose-insulin kinetics： A theoretical study

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International Journal of Biomathematics 2017年第4期10卷 153-172页

作者： amit Mondal Mitul Islam Nurul Islam Department of Mathematics Jafarpur Kashinath High school P. O. Champahati P. S. Sonarpur 24 Pgs(S) Pin 743330 India Indian statistical Institute 203 B. T. Road Kolkata 700108 India Department of Mathematics Ramakrishna Mission College (Autonomous) Narendrapur Kolkata 700103 India

In this paper, we present a modified minima] model for glucose and insulin kinetics model. The model proposed here is a smooth approximation of the original non-smooth minimal model. The dynamical properties like dissipativity, existence of equilibrium and stability of the system at the equilibrium points are investigated. A linear feedback-based control strategy is studied to control the blood glucose level in the situation where the physical system fails to regulate the blood glucose level automatically. A critical control parameter value kc is determined in terms of the system parameters. Extensive numerical simulation is performed with different parameter sets. Assuming different values for the feedback gain parameter, ranges of physiological parameter a are determined where the feedback gain is sufficient to stabilize the control system.

关键词： stability analysis control glucose and insulin kinetics minimal model.

Longitudinally extensive transverse myelitis associated with scrub typhus:A case report

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Asian Pacific Journal of Tropical Medicine 2024年第8期17卷 375-378页

作者： amit Kumar Rajesh Chetiwal shweta Tanwar Department of Medicine ESIC Postgraduate Institute of Medical Sciences and ResearchBasaidarapurNew DelhiIndia Indian Council of Medical Research New DelhiIndia

Rationale:Longitudinally extensive transverse myelitis(LETM)is a rare inflammatory demyelinating disease predominantly associated with autoimmune and inflammatory *** typhus can cause a variety of neurological complications,which may result in poor recovery and long-term *** report reveals a rare linkage between LETM and scrub *** concerns:A 24-year-old female presented with a history of fever for 10 days associated with progressive *** examination revealed bilateral lower limb weakness(grade 0/5)and bilateral upper limb weakness(grade 2/5)with reduced sensation below the T3 ***:scrub typhus presenting with longitudinally extensive transverse ***:steroid pulse therapy with antibiotics supported by early intensive ***:Complete recovery was ***:This case report highlights the importance of considering scrub typhus as a potential cause of LETM in endemic regions,particularly in patients presenting with febrile illness and neurological symptoms.

关键词： Longitudinally extensive transverse myelitis scrub typhus Orientia tsutsugamushi Case report

Fully fuzzy linear systems of triangular fuzzy numbers(a,b,c)

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International Journal of Intelligent Computing and Cybernetics 2013年第1期6卷 21-44页

作者： amit Kumar Abhinav Bansal Neetu Babbar school of Mathematics and Computer Applications Thapar UniversityPatialaIndia Department of Computer science and Engineering Thapar UniversityPatialaIndia

Purpose–The purpose of this paper is to study a nascent theory and an emerging concept of solving a fully fuzzy linear system(FFLs)with no non negative restrictions on the triangular fuzzy numbers chosen as *** new simplified computational methods are proposed to solve a FFLs without any sign *** first method eliminates the non-negativity constraint from the coefficient matrix while the second method eliminates the constraint of non-negativity on the solution *** methods are introduced with an objective to broaden the domain of fuzzy linear systems to encompass a wide range of problems occurring in ***/methodology/approach–The design of numerical methods is motivated by decomposing the fuzzy based linear system into its equivalent crisp linear form which can be further solved by variety of classical methods to solve a crisp linear *** the paper investigates schur complement technique to solve the crisp equivalent of the ***–The results that are obtained reveal interesting properties of a *** using the proposed methods,the authors are able to check the consistency of the fuzzy linear system as well as obtain the nature of obtained solutions,***,unique or *** it is also seen that an n£n FFLs may yield finitely many solutions which may not be entirely feasible(strong).Also the methods successfully remove the non-negativity restriction on the coefficient matrix and the solution vector,*** limitations/implications–Evolving methods with better computational complexity and that which remove the non-negativity restriction jointly on all the parameters are left as an open ***/value–The proposed methods are new and conceptually simple to understand and apply in several scientific areas where fuzziness *** methods successfully remove several constraints that have been employed exhaustively by researchers and thus eventually tend to widen the breadt

关键词： Fully fuzzy linear system(FFLs) Triangular fuzzy numbers schur complement Fuzzy arithmetic Fuzzy logic Mathematics

Recent developments in computational modelling of nucleation in phase transformations

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npj Computational Materials 2016年第1期2卷 180-188页

作者： Lei Zhang Weiqing Ren amit samanta Qiang Du Beijing International Center for Mathematical Research Center for Quantitative BiologyPeking UniversityBeijingChina Department of Mathematics National University of SingaporeSingapore Institute of High Performance Computing Agency for ScienceTechnology and ResearchSingapore Physics Division Lawrence Livermore National LaboratoryLivermoreCAUSA Department of Applied Physics and Applied Mathematics Columbia UniversityNew YorkNYUSA

Nucleation is one of the most common physical phenomena in physical,chemical,biological and materials *** to the complex multiscale nature of various nucleation events and the difficulties in their direct experimental observation,development of effective computational methods and modeling approaches has become very important and is bringing new light to the study of this challenging *** discussions in this manuscript provide a sampler of some newly developed numerical algorithms that are widely applicable to many nucleation and phase transformation *** first describe some recent progress on the design of efficient numerical methods for computing saddle points and minimum energy paths,and then illustrate their applications to the study of nucleation events associated with several different physical systems.

关键词： transformation phase bringing

Combustion enhancement in rearward step based scramjet combustor by air injection at step base

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Propulsion and Power Research 2021年第3期10卷 224-234页

作者： amit Thakur Nishanth Thillai Amritesh sinha Mechanical Engineering PES UniversityIndia Institute for Aerospace studies University of TorontoCanada Aerodynamics Energetics and PropulsionISAE SupaeroFrance

Numerical simulations were performed to model the non-reacting and reacting flow behind a rearward step flameholder in Mach 1.6 supersonic flow with fuel injection at the step *** combustor geometry was based on the University of Florida scramjet experimental *** was modeled using k-u shear stress transport(ssT),laminar flamelet was used for combustion *** static pressure showed good agreement with experimental data for non-reacting and reacting *** non-reacting flow,dummy fuel helium mole fraction distribution in the recirculation region behind the step was validated with planar laser induced fluorescence(PLIF)images in *** improve the combustion characteristics,air was injected in tandem with hydrogen at step base using various *** all fuel injection as baseline,the case with 2 air jets around each fuel jet and air injected at 2 times the stagnation pressure of fuel showed the most improvement compared to other *** was most effective in reducing the local fuel richness,shortening the flame length and increasing combustion efficiency.

关键词： step flameholder scramjet combustor Local equivalence ratio Air injection Combustion efficiency

Merging bound states in the continuum in an open acoustic resonator

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem s.Pilipchuk sibo Huang Chen shen Almas F.sadreev Yong Li Andrey E.Miroshnichenko school of Physics and Electronic sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical Engineering Rowan University school of Engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Deep Learning-Assisted OFDM Detection with Hardware Impairments

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Journal of Communications and Information Networks 2023年第4期8卷 378-388页

作者： amit singh sanjeev sharma Kuntal Deka Vimal Bhatia Indian Institute of Technology(IIT)BHU Varanasi Varanasi 221005India Indian Institute of Technology(IIT)Guwahati Guwahati 781039India Indian Institute of Technology(IIT)Indore Indore 452020India

This paper introduces a deep learning(DL)algorithm for estimating doubly-selective fading channel and detecting signals in orthogonal frequency division multiplexing(OFDM)communication systems affected by hardware impairments(HIs).In practice,hardware imperfections are present at the transceivers,which are modeled as direct current(DC)offset,carrier frequency offset(CFO),and in-phase and quadrature-phase(IQ)imbalance at the transmitter and the receiver in OFDM *** HIs,the explicit system model could not be mathematically derived,which limits the performance of conventional least square(Ls)or minimum mean square error(MMsE)***,we consider time-frequency response of a channel as a 2D image,and unknown values of the channel response are derived using known values at the pilot locations with DL-based image super-resolution,and image restoration ***,a deep neural network(DNN)is designed to fit the mapping between the received signal and transmit symbols,where the number of outputs equals to the size of the modulation *** show that there are no significant effects of HIs on channel estimation and signal detection in the proposed DL-assisted *** proposed DL-assisted detection improves the OFDM performance as compared to the conventional Ls/MMsE under severe Hls.

关键词： OFDM DL HIs channel estimation signal detection

Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

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Neural Regeneration Research 2025年第9期20卷 2454-2463页

作者： Victoria Jiménez Carretero IrisÁlvarez-Merz Jorge Hernández-Campano sergei A.Kirov Jesús M.Hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain Ramón y Cajal Institute for Health Research(IRYCIs) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of Neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neuroscience and Regenerative Medicine&Department of Neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate *** N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor ***,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

Polymer flooding and its effects on enhanced oil recovery special reference to Upper Assam Basin

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Petroleum Research 2023年第1期8卷 54-62页

作者： Kalpajit Hazarika subrata Borgohain Gogoi amit Kumar Presidency University BangaloreIndia Dibrugarh University AssamIndia Rajiv Gandhi Institute of Petroleum Technology JaisAmethiIndia

Chemical Enhance oil Recovery(CEOR)technology is getting more attention since energy crises are getting worse and *** application of polymer flooding depends on the evaluation of rheological and solution properties of injected slug at reservoir conditions,which is function of polymer concentration,salinity,temperature and shear *** acryl amide(PAM)is commonly used polymer in polymer flooding ***,comparative study with other polymers such as xanthan gum(XG)is required while selection of appropriate polymer for *** present study,the recovery efficiency of PAM and XG as a polymer has been evaluated for application as chemical EOR agent for tertiary phase polymer flooding in Upper Assam *** comparative study between PAM and XG has been done in terms of rheological *** flooding experiment of polymer flooding has also been tested to determine the recovery efficiency of the PAM and XG polymer *** results showed that these polymers exhibit favorable salt tolerance,temperature resistance,and recoverable viscosity after shearing,reasonable thickening behavior and improved viscosity enhancement properties due to presence of hydrophobic association in the polymer main *** flooding experiment of polymer flooding has also been tested to determine the recovery efficiency of the PAM and XG polymer *** show that macroscopic sweep efficiency is the dominant factor during *** an injection of hydrogel polymer to the reservoir is to increase a viscosity of fluid containing water so that the fluid is more difficult to flow than the oil,and as a result,the oil production *** thinning behavior was observed in case of PAM indicating predominance of the frontal advance *** PAM seems to be following both piston like movement and frontal advance theory it can be efficiently enhancing the macroscopic sweep efficiency as well as microscopic displacement *** overall

关键词： Rheology Polymer Macroscopic Microscopic EOR