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Multigrid Method for the Chan-Vese Model in Variational Segmentation

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Communications in Computational Physics 2008年第7期4卷 294-316页

作者： noor badshah Ke Chen Department of Mathematical Sciences University of LiverpoolLiverpool L693BXUK.

The Chan-Vese method of active contours without edges[11]has been used successfully for segmentation of images.As a variational formulation,it involves the solution of a fully nonlinear partial differential equation which is usually solved by using time marching methods with semi-implicit schemes for a parabolic equation;the recent method of additive operator splitting[19,36]provides an effective acceleration of such schemes for images of moderate size.However to process images of large size,urgent need exists in developing fast multilevel methods.Here we present a multigrid method to solve the Chan-Vese nonlinear elliptic partial differential equation,and demonstrate the fast convergence.We also analyze the smoothing rates of the associated smoothers.Based on our numerical tests,a surprising observation is that our multigrid method is more likely to converge to the global minimizer of the particular non-convex problem than previously unilevel methods which may get stuck at local minimizers.Numerical examples are given to show the expected gain in CPU time and the added advantage of global solutions.

关键词： Active contours energy minimization partial differential equations segmentation level sets total variation multigrid.

Structural, morphological, Raman, optical, magnetic, and antibacterial characteristics of CeO2 nanostructures

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International Journal of Minerals,Metallurgy and Materials 2016年第1期23卷 102-108页

作者： Fazal Abbas Javed Iqbal Tariq Jan noor badshah Qaisar Mansoor Muhammad Ismail Laboratory of Nanoscience and Technology Department of Physics International Islamic University H-10 Islamabad 44000 Pakistan Department of Basic Science University of Engineering and Technology Peshawar 26000 Pakistan Institute of Biomedical and Genetic Engineering (IBGE) Islamabad 44000 Pakistan

In this study, CeO2 nanostructures were synthesized by a soft chemical method. A hydrothermal treatment was observed to lead to an interesting morphological transformation of the nanoparticles into homogeneous microspheres composed of nanosheets with an average thickness of 40 nm. Structural analysis revealed the formation of a single-phase cubic fluorite structure of CeO2 for both samples. A Raman spectroscopic study confirmed the XRD results and furthermore indicated the presence of a large number of oxygen vacancies in the nanosheets. These oxygen vacancies led to room-temperature ferromagnetism （RTFM） of the CeO2 nanosheets with enhanced magnetic characteristics. Amazingly, the nanosheets exhibited substantially greater antibacterial activity than the nanoparticles. This greater antibacte- rial activity was attributed to greater exposure of high-surface-energy polar surfaces and to the presence of oxygen vacancies.

关键词： ceciurn oxide nanosheets chemical synthesis ferromagnetism oxygen vacancies antibacterial properties

Mathematical approaches for optimization of dengue fever dynamics

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International Journal of Modeling, Simulation, and Scientific Computing 2019年第2期10卷 133-141页

作者： Didar Murad noor badshah Muhammad Ali Syed Department of Pure and Applied Mathematics The University of Haripur Pakistan Department of Basic Sciences The University of Engineering and Technology Peshawar Pakistan Department of Microbiology The University of Haripur Pakistan

Background and Objective:For dengue outbreak prevention and vectors reduction,fundamental role of control parameters like vaccination against dengue virus in human population and insecticide in mosquito population have been addressed theoretically and numerically.For this purpose,an existing model was modified to optimize dengue fever.Methodology:Using Pontryagin’s maximum principle,the dynamics of infection for the optimal control problem was addressed,further,defined cost functional,established existence of optimal control,stated Hamiltonian for characterization of optimization.Results:Numerical simulations for optimal state variables and control variables were performed.Conclusion:Our findings demonstrate that with low cost of control variables,state variable such as recovered population increases gradually and decrease other state variables for host and vector population.

关键词： Dengue optimal control theory cost functional cost weights Hamiltonian

Radiative Blood-Based Hybrid Copper-Graphene Nanoliquid Flows along a Source-Heated Leaning Cylinder

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 1017-1037页

作者： Siti Nur Ainsyah Ghani noor Fadiya Mohd noor Institute of Mathematical Sciences Faculty of ScienceUniversiti MalayaKuala Lumpur50603Malaysia Center for Data Analytics Consultancy&Services(UM-CDACS) Faculty of ScienceUniversiti MalayaKuala Lumpur50603Malaysia

Variant graphene,graphene oxides(GO),and graphene nanoplatelets(GNP)dispersed in blood-based copper(Cu)nanoliquids over a leaning permeable cylinder are the focus of this study.These forms of graphene are highly beneficial in the biological and medical fields for cancer therapy,anti-infection measures,and drug delivery.The non-Newtonian Sutterby(blood-based)hybrid nanoliquid flows are generalized within the context of the Tiwari-Das model to simulate the effects of radiation and heating sources.The governing partial differential equations are reformulated into a nonlinear set of ordinary differential equations using similar transformational expressions.These equations are then transformed into boundary value problems through a shooting technique,followed by the implementation of the bvp4c tool in MATLAB.The influences of various parameters on the model’s nondimensional velocity and temperature profiles,reduced skin friction,and reduced Nusselt number are presented for detailed discussions.The results indicated that Cu-GNP/blood and Cu-GO/blood hybrid nanofluids exhibit the lowest and highest velocity distributions,respectively,for increased nanoparticles volume fraction,curvature parameter,Sutterby fluid parameter,Hartmann number,and wall permeability parameter.Conversely,opposite trends are observed for the temperature distribution for all considered parameters,except the mixed convection parameter.Increases in the reduced skin friction magnitude and the reduced Nusselt number with higher values of graphene/GO/GNP nanoparticle volume fraction are also reported.Finally,GNP is identified as the superior heat conductor,with an average increase of approximately 5%and a peak of 7.8%in the reduced Nusselt number compared to graphene and GO nanoparticles in the Cu/blood nanofluids.

关键词： Hybrid nanofluid sutterby fluid tiwari-das model thermal radiation graphene graphene oxides graphene nanoplatelets

Prediction of corrosion rate for friction stir processed WE43 alloy by combining PSO-based virtual sample generation and machine learning

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Journal of Magnesium and Alloys 2024年第4期12卷 1518-1528页

作者： Annayath Maqbool Abdul Khalad noor Zaman Khan Department of Mechanical Engineering National Institute of Technology SrinagarJ&K 190006India Department of Mechanical Engineering Indian Institute of TechnologyHyderabadSangareddyTelangana 502284India School of Engineering Deakin UniversityVictoria 3216Australia

The corrosion rate is a crucial factor that impacts the longevity of materials in different applications.After undergoing friction stir processing(FSP),the refined grain structure leads to a notable decrease in corrosion rate.However,a better understanding of the correlation between the FSP process parameters and the corrosion rate is still lacking.The current study used machine learning to establish the relationship between the corrosion rate and FSP process parameters(rotational speed,traverse speed,and shoulder diameter)for WE43 alloy.The Taguchi L27 design of experiments was used for the experimental analysis.In addition,synthetic data was generated using particle swarm optimization for virtual sample generation(VSG).The application of VSG has led to an increase in the prediction accuracy of machine learning models.A sensitivity analysis was performed using Shapley Additive Explanations to determine the key factors affecting the corrosion rate.The shoulder diameter had a significant impact in comparison to the traverse speed.A graphical user interface(GUI)has been created to predict the corrosion rate using the identified factors.This study focuses on the WE43 alloy,but its findings can also be used to predict the corrosion rate of other magnesium alloys.

关键词： Corrosion rate Friction stir processing Virtual sample generation Particle swarm optimization Machine learning Graphical user interface

Neural network study of the nuclear ground-state spin distribution within a random interaction ensemble

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Nuclear Science and Techniques 2024年第3期35卷 216-227页

作者： Deng Liu Alam noor A Zhen-Zhen Qin Yang Lei School of Mathematics and Physics Southwest University of Science and TechnologyMianyang 621010China School of Nuclear Science and Technology Southwest University of Science and TechnologyMianyang 621010China

The distribution of the nuclear ground-state spin in a two-body random ensemble(TBRE)was studied using a general classification neural network(NN)model with two-body interaction matrix elements as input features and the corresponding ground-state spins as labels or output predictions.The quantum many-body system problem exceeds the capability of our optimized NNs in terms of accurately predicting the ground-state spin of each sample within the TBRE.However,our NN model effectively captured the statistical properties of the ground-state spin because it learned the empirical regularity of the ground-state spin distribution in TBRE,as discovered by physicists.

关键词： Neural network Two-body random ensemble Spin distribution of nuclear ground state

Conservation laws,Lie symmetries,self adjointness,and soliton solutions for the Selkov–Schnakenberg system

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Communications in Theoretical Physics 2024年第2期76卷 29-44页

作者： Kashif Ali Aly R Seadawy Syed T R Rizvi noor Aziz Department of Mathematics COMSATS University IslamabadLahore CampusPakistan Mathematics Department Faculty of ScienceTaibah UniversityAl-Madinah Al-Munawarah41411Saudi Arabia

In this article,we explore the famous Selkov–Schnakenberg(SS)system of coupled nonlinear partial differential equations(PDEs)for Lie symmetry analysis,self-adjointness,and conservation laws.Moreover,miscellaneous soliton solutions like dark,bright,periodic,rational,Jacobian elliptic function,Weierstrass elliptic function,and hyperbolic solutions of the SS system will be achieved by a well-known technique called sub-ordinary differential equations.All these results are displayed graphically by 3D,2D,and contour plots.

关键词： Selkov-Schnakenberg system Lie symmetry analysis conservation laws adjointness integrability

Aldosterone synthase inhibitor“Baxdrostat”for resistant hypertension:A clinical approach or futuristic idea?

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Chronic Diseases and Translational Medicine 2024年第2期10卷 146-148页

作者： Muhammad Osama Siddiqui Ayaan Ahmed Qureshi Arooba Siddiqui noor ul ain Liaquat National Hospital and Medical College KarachiSindhPakistan Karachi Medical and Dental College KarachiSindhPakistan

The American College of Cardiology/American Heart Association defines resistant hypertension(RH)as a clinical blood pressure(BP)reading of>130/80 mmHg in patients taking three antihypertensive drugs,including a renin–angiotensin system inhibitor,a calcium channel blocker(CCB),and a diuretic at well-tolerated doses.1,2 It is reported from multiple population-based surveys that in the United States,there is an approximately 12%–15%prevalence of RH among adults diagnosed with hypertension.2 A prospective study demonstrates that 20%of people diagnosed with RH had primary hyperaldosteronism.3,4 In addition to the classic three antihypertensive drugs,spironolactone and mineralocorticoid are also administered for RH.However,with respect to the safety profile of spironolactone,it has been reported to have several side effects such as low testosterone production,menstrual irregularities,and excessively raised serum potassium levels,leaving the drug unfit for the longitudinal therapeutic purpose of treating RH.

关键词： hypertension drugs hypertensive

IoT Smart Devices Risk Assessment Model Using Fuzzy Logic and PSO

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Computers, Materials & Continua 2024年第2期78卷 2245-2267页

作者： Ashraf S.Mashaleh noor Farizah Binti Ibrahim Mohammad Alauthman Mohammad Almseidin Amjad Gawanmeh School of Computer Sciences Universiti Sains MalaysiaPenangMalaysia Department Computer Center Al-Balqa Applied UniversitySaltJordan Department of Information Security Faculty of Information TechnologyUniversity of PetraAmmanJordan Department of Computer Science Tafila Technical UniversityTafilaJordan College of Engineering and IT University of DubaiDubaiUnited Arab Emirates

Increasing Internet of Things(IoT)device connectivity makes botnet attacks more dangerous,carrying catastrophic hazards.As IoT botnets evolve,their dynamic and multifaceted nature hampers conventional detection methods.This paper proposes a risk assessment framework based on fuzzy logic and Particle Swarm Optimization(PSO)to address the risks associated with IoT botnets.Fuzzy logic addresses IoT threat uncertainties and ambiguities methodically.Fuzzy component settings are optimized using PSO to improve accuracy.The methodology allows for more complex thinking by transitioning from binary to continuous assessment.Instead of expert inputs,PSO data-driven tunes rules and membership functions.This study presents a complete IoT botnet risk assessment system.The methodology helps security teams allocate resources by categorizing threats as high,medium,or low severity.This study shows how CICIoT2023 can assess cyber risks.Our research has implications beyond detection,as it provides a proactive approach to risk management and promotes the development of more secure IoT environments.

关键词： IoT botnet detection risk assessment fuzzy logic particle swarm optimization(PSO) cybersecurity interconnected devices