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OPTIMAL STUDY OF SCHISTOSOMIASIS IN HUMANS WITH ENVIRONMENTAL TRANSMISSION VIA FRACTIONAL ORDER MATHEMATICAL MODEL
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作者 Z.AVAZZADEH H.HASSANI +2 位作者 A.Bayati ESHKAFTAKI M.J.EBADI S.MEHRABI 《Acta Mathematica Scientia》 2025年第5期2279-2298,共20页
Background:Schistosomiasis is a parasitic disease.It is caused by a prevalent infection in tropical areas and is transmitted through contaminated water with larvae parasites.Schistosomiasis is the second most parasiti... Background:Schistosomiasis is a parasitic disease.It is caused by a prevalent infection in tropical areas and is transmitted through contaminated water with larvae parasites.Schistosomiasis is the second most parasitic disease globally,so investigating its prevention and treatment is crucial.Methods:This paper aims to suggest a time-fractional model of schistosomiasis disease(T-FMSD)in the sense of the Caputo operator.The T-FMSD considers the dynamics involving susceptible ones not infected with schistosomiasis(S_(h)(t)),those infected with the infection(Ih(t)),those recovering from the disease(R(t)),susceptible snails with and without schistosomiasis infection,respectively shown by I_(v)(t)and S_(v)(t).We use a new basis function,generalized Bernoulli polynomials,for the approximate solution of T-FMSD.The operational matrices are incorporated into the method of Lagrange multipliers so that the fractional problem can be transformed into an algebraic system of equations.Results:The existence and uniqueness of the solution,and the convergence analysis of the model are established.The numerical computations are graphically presented to depict the variations of the compartments with time for varied fractional order derivatives.Conclusions:The proposed method not only provides an accurate solution but also can accurately predict schistosomiasis transmission.The results of this study will assist medical scientists in taking necessary measures during screening and treatment processes. 展开更多
关键词 SCHISTOSOMIASIS SUSCEPTIBLE INFECTED generalized Bernoulli polynomials opti-mization method
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A state-of-the-art Fuzzy Nonlinear Additive Regression(FNAR)model for groundwater level prediction
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作者 Sepideh Zeraati Neyshabouri Abbas Khashei-Siuki Mohammad Ghasem Akbari 《Journal of Groundwater Science and Engineering》 2026年第1期83-99,共17页
Groundwater modeling remains challenging due to heterogeneity and complexity of aquifer systems,necessitating endeavors to quantify Groundwater Levels(GWL)dynamics to inform policymakers and hydrogeologists.This study... Groundwater modeling remains challenging due to heterogeneity and complexity of aquifer systems,necessitating endeavors to quantify Groundwater Levels(GWL)dynamics to inform policymakers and hydrogeologists.This study introduces a novel Fuzzy Nonlinear Additive Regression(FNAR)model to predict monthly GWL in an unconfined aquifer in eastern Iran,using a 19-year(1998–2017)dataset from 11 piezometric wells.Under three distinct scenarios with progressively increasing input complexity,the study utilized readily available climate data,including Precipitation(Prc),Temperature(Tave),Relative Humidity(RH),and Evapotranspiration(ETo).The dataset was split into training(70%)and validation(30%)subsets.Results showed that among three input scenarios,Scenario 3(Sc3,incorporating all four variables)achieved the best predictive performance,with RMSE ranging from 0.305 m to 0.768 m,MAE from 0.203 m to 0.522 m,NSE from 0.661 to 0.980,and PBIAS from 0.771%to 0.981%,indicating low bias and high reliability.However,Sc2(excluding ETo)with RMSE ranging from 0.4226 m to 0.9909 m,MAE from 0.3418 m to 0.8173 m,NSE from 0.2831 to 0.9674,and PBIAS from−0.598%to 0.968%across different months offers practical advantages in data-scarce settings.The FNAR model outperforms conventional Fuzzy Least Squares Regression(FLSR)and holds promise for GWL forecasting in data-scarce regions where physical or numerical models are impractical.Future research should focus on integrating FNAR with deep learning algorithms and real-time data assimilation expanding applications across diverse hydrogeological settings. 展开更多
关键词 Birjand aquifer Data-scarce regions Fuzzy-based approach Groundwater table Novel statistical model Soft computing
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Artificial Neural Network-Based Flow and Heat Transfer Analysis of Williamson Nanofluid over a Moving Wedge:Effects of Thermal Radiation,Viscous Dissipation,and Homogeneous-Heterogeneous
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作者 Adnan Ashique Nehad Ali Shah +3 位作者 Usman Afzal Yazen Alawaideh Sohaib Abdal Jae Dong Chung 《Computer Modeling in Engineering & Sciences》 2026年第2期642-664,共23页
There is a need for accurate prediction of heat and mass transfer in aerodynamically designed,non-Newtonian nanofluids across aerodynamically designed,high-flux biomedical micro-devices for thermal management and reac... There is a need for accurate prediction of heat and mass transfer in aerodynamically designed,non-Newtonian nanofluids across aerodynamically designed,high-flux biomedical micro-devices for thermal management and reactive coating processes,but existing work is not uncharacteristically remiss regarding viscoelasticity,radiative heating,viscous dissipation,and homogeneous–heterogeneous reactions within a single scheme that is calibrated.This research investigates the flow of Williamson nanofluid across a dynamically wedged surface under conditions that include viscous dissipation,thermal radiation,and homogeneous-heterogeneous reactions.The paper develops a detailed mathematical approach that utilizes boundary layers to transform partial differential equations into ordinary differential equations using similarity transformations.RK4 is the technique for gaining numerical solutions,but with the addition of ANNs,there is an improvement in prediction accuracy and computational efficiency.The study investigates the influence of wedge angle parameter,along with Weissenberg number,thermal radiation parameter and Brownian motion parameter,and Schmidt number,on velocity distribution,temperature distribution,and concentra-tion distribution.Enhanced Weissenberg numbers enhance viscoelastic responses that modify velocity patterns,but radiation parameters and thermophoresis have key impacts on thermal transfer phenomena.This research develops findings that are of enormous application in aerospace,biomedical(artificial hearts and drug delivery),and industrial cooling technology applications.New findings on non-Newtonian nanofluids under full flow systems are included in this work to enhance heat transfer methods in novel fluid-based systems. 展开更多
关键词 Williamson fluid thermal radiation viscous dissipation Artificial Neural Networks(ANNs) homogeneous-heterogeneous reactions
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Radiative Features of Darcy Forchheimer Flow of Entropy-Optimized Cross Flow Conveying Ternary Hybrid Nanofluid Past a Stretching Cylinder
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作者 M.Faizan Syed Sohaib Zafar +3 位作者 Farhan Ali Umair Khan Aurang Zaib Najiyah Safwa Khashi’ie 《Frontiers in Heat and Mass Transfer》 2026年第1期97-119,共23页
The purpose of the present investigation is to explore the implications of Cross fluid in a Darcy-Forchheimer porousmediumdue to the tri-hybrid nanofluid past a porous cylinder.Thermal radiation,heat generation,therma... The purpose of the present investigation is to explore the implications of Cross fluid in a Darcy-Forchheimer porousmediumdue to the tri-hybrid nanofluid past a porous cylinder.Thermal radiation,heat generation,thermal convection,solutal convective and chemical reaction have been encountered in this analysis.Entropy generation has been accounted for under the fluidic friction,heat rate analysis,and porosity analysis.Three different nanoparticles of multiwall carbon nanotube(MWCNT),aluminum oxide(Al_(2)O_(3)),and silver(Ag)are utilized to illustrate the tri-hybrid nanofluid flow with Ethlene Glycol(EG)as the base fluid.The governance model,consisting of linked inadequate differential conditions,is transformed into an ordinary configuration of nonlinear coupled differential conditions by acceptable adjustments.The obtained outcomes in combination with the bvp4c approach are then used to resolve the generated ODEs.For discussion purposes,the impacts of the physical limitations on temperature profile,velocity,and concentration have also been illustrated.Numerical results have been obtained for the diffusion rate,heat transfer rate,drag force,and other factors.While the Forchheimer parameter and the inclination angle reduce the fluid flow’s velocity,the Biot number of heat and mass transfer influences the fluid’s temperature.According to the findings,hybrid nanofluid is the most effective way to improve heat transmission and may also be utilized for cooling.Three different kinds of nanofluids were used in a comparative examination to clarify the study’s conclusions.Changes in viscosity and porousness caused the nanofluids’velocity to drop by 13.12%and 15.8%,respectively;however,trihybrid nanofluids with improved convection showed a 13.12%rise. 展开更多
关键词 Stretching cylinder tri-hybrid nanofluid thermal radiation cross fluid heat source/sink
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Noninvasive Radar Sensing Augmented with Machine Learning for Reliable Detection of Motor Imbalance
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作者 Faten S.Alamri Adil Ali Saleem +2 位作者 Muhammad I.Khan Hafeez Ur Rehman Siddiqui Amjad Rehman 《Computer Modeling in Engineering & Sciences》 2026年第1期698-726,共29页
Motor imbalance is a critical failure mode in rotating machinery,potentially causing severe equipment damage if undetected.Traditional vibration-based diagnostic methods rely on direct sensor contact,leading to instal... Motor imbalance is a critical failure mode in rotating machinery,potentially causing severe equipment damage if undetected.Traditional vibration-based diagnostic methods rely on direct sensor contact,leading to installation challenges and measurement artifacts that can compromise accuracy.This study presents a novel radar-based framework for non-contact motor imbalance detection using 24 GHz continuous-wave radar.A dataset of 1802 experimental trials was sourced,covering four imbalance levels(0,10,20,30 g)across varying motor speeds(500–1500 rpm)and load torques(0–3 Nm).Dual-channel in-phase and quadrature radar signals were captured at 10,000 samples per second for 30-s intervals,preserving both amplitude and phase information for analysis.A multi-domain feature extraction methodology captured imbalance signatures in time,frequency,and complex signal domains.From 65 initial features,statistical analysis using Kruskal–Wallis tests identified significant descriptors,and recursive feature elimination with Random Forest reduced the feature set to 20 dimensions,achieving 69%dimensionality reduction without loss of performance.Six machine learning algorithms,Random Forest,Extra Trees Classifier,Extreme Gradient Boosting,Categorical Boosting,Support Vector Machine with radial basis function kernel,and k-Nearest Neighbors were evaluated with grid-search hyperparameter optimization and five-fold cross-validation.The Extra Trees Classifier achieved the best performance with 98.52%test accuracy,98%cross-validation accuracy,and minimal variance,maintaining per-class precision and recall above 97%.Its superior performance is attributed to its randomized split selection and full bootstrapping strategy,which reduce variance and overfitting while effectively capturing the nonlinear feature interactions and non-normal distributions present in the dataset.The model’s average inference time of 70 ms enables near real-time deployment.Comparative analysis demonstrates that the radar-based framework matches or exceeds traditional contact-based methods while eliminating their inherent limitations,providing a robust,scalable,and noninvasive solution for industrial motor condition monitoring,particularly in hazardous or space-constrained environments. 展开更多
关键词 Condition monitoring imbalance detection industrial applications machine learning motor fault diagnosis non-contact sensing radar sensing vibration monitoring
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Spatiotemporal Variability of Influencing Factors on Tuberculosis Incidence in Jiangsu Province,China during 2011−2021
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作者 Yifan Tang Tenglong Li +7 位作者 Cheng Chen Kai Wang Mingming Chen Junhui Lin Sifan Wang Limei Zhu Chengxiu Ling Qiao Liu 《Biomedical and Environmental Sciences》 2026年第2期234-238,共5页
Tuberculosis(TB),one of the oldest infectious diseases caused by Mycobacterium tuberculosis,poses a considerable challenge to global public health.There are approximately 10 million new TB cases worldwide annually,and... Tuberculosis(TB),one of the oldest infectious diseases caused by Mycobacterium tuberculosis,poses a considerable challenge to global public health.There are approximately 10 million new TB cases worldwide annually,and TB claims the lives of nearly 3 million people each year,making it one of the leading causes of death from a single infectious disease[1].China ranks third globally in terms of TB burden,with approximately 733,000 TB cases reported in 2023[2].Based on the ecological model of health determinants developed by Whitehead and Dahlgren,health determinants can be classified into direct causes. 展开更多
关键词 tuberculosis incidence infectious diseases influencing factors mycobacterium tuberculosisposes spatiotemporal variability China ecological model health determinants jiangsu province
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CamSimXR:eXtended Reality(XR)Based Pre-Visualization and Simulation for Optimal Placement of Heterogeneous Cameras
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作者 Juhwan Kim Gwanghyun Jo Dongsik Jo 《Computers, Materials & Continua》 2026年第3期1920-1939,共20页
In recent years,three-dimensional reconstruction technologies that employ multiple cameras have continued to evolve significantly,enabling remote collaboration among users in extended Reality(XR)environments.In additi... In recent years,three-dimensional reconstruction technologies that employ multiple cameras have continued to evolve significantly,enabling remote collaboration among users in extended Reality(XR)environments.In addition,methods for deploying multiple cameras for motion capture of users(e.g.,performers)are widely used in computer graphics.As the need to minimize and optimize the number of cameras grows to reduce costs,various technologies and research approaches focused on Optimal Camera Placement(OCP)are continually being proposed.However,as most existing studies assume homogeneous camera setups,there is a growing demand for studies on heterogeneous camera setups.For instance,technical demands keep emerging in scenarios with minimal camera configurations,especially regarding cost factors,the physical placement of cameras given the spatial structure,and image capture strategies for heterogeneous cameras,such as high-resolution RGB cameras and depth cameras.In this study,we propose a pre-visualization and simulation method for the optimal placement of heterogeneous cameras in XR environments,accounting for both the specifications of heterogeneous cameras(e.g.,field of view)and the physical configuration(e.g.,wall configuration)in real-world spaces.The proposed method performs a visibility analysis of cameras by considering each camera’s field-of-view volume,resolution,and unique characteristics,along with physicalspace constraints.This approach enables the optimal position and rotation of each camera to be recommended,along with the minimum number of cameras required.In the results of our study conducted in heterogeneous camera combinations,the proposed method achieved 81.7%~82.7%coverage of the target visual information using only 2~3 cameras.In contrast,single(or homogeneous)-typed cameras were required to use 11 cameras for 81.6%coverage.Accordingly,we found that camera deployment resources can be reduced with the proposed approaches. 展开更多
关键词 Optimal camera placement heterogeneous cameras extended reality pre-visualization simulation multi-cameras
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Novel Analysis of SiO_(2)+ZnO+MWCN T-Ternary Hybrid Nanofluid Flow in Electromagnetic Squeezing Systems
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作者 Muhammad Hamzah Muhammad Ramzan +3 位作者 Abdulrahman A.Almehizia Ibrahim Mahariq Laila A.Al-Essa Ahmed S.Hassan 《Computer Modeling in Engineering & Sciences》 2026年第1期604-626,共23页
The present investigation inspects the unsteady,incompressible MHD-induced flow of a ternary hybrid nanofluid made of SiO_(2)(silicon dioxide),ZnO(zinc oxide),and MWCNT(multi-walled carbon nanotubes)suspended in a wat... The present investigation inspects the unsteady,incompressible MHD-induced flow of a ternary hybrid nanofluid made of SiO_(2)(silicon dioxide),ZnO(zinc oxide),and MWCNT(multi-walled carbon nanotubes)suspended in a water-ethylene glycol base fluid between two perforated squeezing Riga plates.This problem is important because it helps us understand the complicated connections between magnetic fields,nanofluid dynamics,and heat transport,all of which are critical for designing thermal management systems.These findings are especially useful for improving the design of innovative cooling technologies in electronics,energy systems,and healthcare applications.No prior study has been done on the theoretical study of the flow of ternary nanofluid(SiO_(2)+ZnO+MWCNT/Water−EthylGl ycol,(60∶40))past a pierced squeezed Riga plates using the boundary value problem solver 4th-order collocation(BVP4C)numerical approach to date.So,the current work has been carried out to fill this gap,and the core purpose of this study is to explore the aspects that enhance the heat transfer of base fluids(H_(2)O/EG)suspended with three nanomaterials SiO_(2),ZnO,and MWCNT.The Riga plates introduce electromagnetic forcing through an embedded array of magnets and electrodes,generating Lorentz forces to regulate the flow.The squeezing effect introduces dynamic boundary movement,which enhances mixing;however,permeability,due to porosity,replicates the true material limits.Similarity transformations of the Navier-Stokes and energy equations result in a highly nonlinear set of ordinary differential equations that govern momentum and thermal energy transport.The subsequent boundary value problem is solved utilizing the BVP4C numerical approach.The study observes the impact of magnetic parameters,squeezing velocity,solid volume percentages of the three nanoparticles,and porous medium factors on velocity and temperature fields.Results show that magnetic fields reduce the velocity profile by 6.75%due to increased squeezing and medium effects.Tri-hybrid nanofluids notice a 9%rise in temperature with higher thermal radiation. 展开更多
关键词 Ternary hybrid nanofluid thermal radiation MATLAB Riga plates porous medium squeezing flow electromagnetic field
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A MATHEMATICAL MODEL OF ENTERPRISE COMPETITIVE ABILITY AND PERFORMANCE THROUGH A PARTICULAR EMDEN-FOWLER EQUATION 被引量:2
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作者 Pai Jente Chang Yueloong Chiu Sumiao 《Acta Mathematica Scientia》 SCIE CSCD 2011年第5期1749-1764,共16页
In this paper we work with the ordinary diffential equation u′′ u3 = 0 and obtain some interesting phenomena concerning blow-up, blow-up rate, life-spann, zeros and critical points of solutions to this equation.
关键词 ESTIMATE life-span BLOW-UP blow-up rate performance competitive ability
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A MATHEMATICAL MODEL OF ENTERPRISE COMPETITIVE ABILITY AND PERFORMANCE THROUGH EMDEN-FOWLER EQUATION FOR SOME ENTERPRISES 被引量:1
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作者 张裕隆 李明融 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1014-1022,共9页
In this paper, we work with the ordinary differential equation n^2u (n)" = u(n)^p and obtain some interesting phenomena concerning, boundedness, blow-up, blow-up rate, life-span of solutions to those equations.
关键词 ESTIMATE life-span BLOW-UP blow-up rate performance competitive ability
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Mathematical modeling of mixed convective MHD Falkner-Skan squeezed Sutterby multiphase flow with non-Fourier heat flux theory and porosity 被引量:1
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作者 Shuguang LI M.I.KHAN +3 位作者 F.ALI S.S.ABDULLAEV S.SAADAOUI HABIBULLAH 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第11期2005-2018,共14页
In a wide variety of mechanical and industrial applications,e.g.,space cooling,nuclear reactor cooling,medicinal utilizations(magnetic drug targeting),energy generation,and heat conduction in tissues,the heat transfer... In a wide variety of mechanical and industrial applications,e.g.,space cooling,nuclear reactor cooling,medicinal utilizations(magnetic drug targeting),energy generation,and heat conduction in tissues,the heat transfer phenomenon is involved.Fourier’s law of heat conduction has been used as the foundation for predicting the heat transfer behavior in a variety of real-world contexts.This model’s production of a parabolic energy expression,which means that an initial disturbance would immediately affect the system under investigation,is one of its main drawbacks.Therefore,numerous researchers worked on such problem to resolve this issue.At last,this problem was resolved by Cattaneo by adding relaxation time for heat flux in Fourier’s law,which was defined as the time required to establish steady heat conduction once a temperature gradient is imposed.Christov offered a material invariant version of Cattaneo’s model by taking into account the upper-connected derivative of the Oldroyd model.Nowadays,both models are combinedly known as the Cattaneo-Christov(CC)model.In this attempt,the mixed convective MHD Falkner-Skan Sutterby nanofluid flow is addressed towards a wedge surface in the presence of the variable external magnetic field.The CC model is incorporated instead of Fourier’s law for the examination of heat transfer features in the energy expression.A two-phase nanofluid model is utilized for the implementation of nano-concept.The nonlinear system of equations is tackled through the bvp4c technique in the MATLAB software 2016.The influence of pertinent flow parameters is discussed and displayed through different sketches.Major and important results are summarized in the conclusion section.Furthermore,in both cases of wall-through flow(i.e.,suction and injection effects),the porosity parameters increase the flow speed,and decrease the heat transport and the influence of drag forces. 展开更多
关键词 sporosity Cattaneo-Christov(CC)heat flux model Falkner-Skan Sutterby nanofluid mixed convection stagnation point
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Mathematical Model of Cerebrospinal Fluid Formation in the Brain
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作者 Faleye Sunday R.Maritz 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期80-80,共1页
In this paper,we present a mathematical model of the cerebrospinal fluid(CSF)formation based on fluid mechanics concepts.Maintenance of intracranial pressure(IP)in the cases of patients with head injury has been a pro... In this paper,we present a mathematical model of the cerebrospinal fluid(CSF)formation based on fluid mechanics concepts.Maintenance of intracranial pressure(IP)in the cases of patients with head injury has been a problem for some time now.Cerebrospinal fluid is one of the cranial vault content that influences the normality of the IP.It was assumed that cerebrospinal fluid(CSF)formation begins as plasma, 展开更多
关键词 CEREBROSPINAL FLUID CEREBRAL CAPILLARY FLUID MECHANICS
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A MATHEMATICAL MODEL OF ENTERPRISE COMPETITIVE ABILITY AND PERFORMANCE THROUGH EMDEN-FOWLER EQUATION (Ⅱ)
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作者 Meng-Rong LI Yue-Loong CHANG Yu-Tso LI 《Acta Mathematica Scientia》 SCIE CSCD 2013年第4期1127-1140,共14页
In this paper we work with the ordinary equation u'' - u2 (u + ) = 0 and ob- tain some interesting phenomena concerning, blow-up, blow-up rate, life-span of solutions to those equations.
关键词 ESTIMATE life-span BLOW-UP blow-up rate performance competitive ability
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Some mathematical aspects of Anderson localization:boundary effect,multimodality,and bifurcation
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作者 Chen Jia Ziqi Liu Zhimin Zhang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2022年第11期45-64,共20页
Anderson localization is a famous wave phenomenon that describes the absence of diffusion of waves in a disordered medium.Here we generalize the landscape theory of Anderson localization to general elliptic operators ... Anderson localization is a famous wave phenomenon that describes the absence of diffusion of waves in a disordered medium.Here we generalize the landscape theory of Anderson localization to general elliptic operators and complex boundary conditions using a probabilistic approach,and further investigate some mathematical aspects of Anderson localization that are rarely discussed before.First,we observe that under the Neumann boundary condition,the low energy quantum states are localized on the boundary of the domain with high probability.We provide a detailed explanation of this phenomenon using the concept of extended subregions and obtain an analytical expression of this probability in the one-dimensional case.Second,we find that the quantum states may be localized in multiple different subregions with high probability in the one-dimensional case and we derive an explicit expression of this probability for various boundary conditions.Finally,we examine a bifurcation phenomenon of the localization subregion as the strength of disorder varies.The critical threshold of bifurcation is analytically computed based on a toy model and the dependence of the critical threshold on model parameters is analyzed. 展开更多
关键词 landscape spectrum EIGENVALUE EIGENMODE EIGENFUNCTION elliptic operator Schr?dinger operator CONFINEMENT
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Computer Science Tools for Manual Editing of Computed Tomographic Images: Impact on the Quality of 3D Printed Models 被引量:1
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作者 Jean H.D.Fasel Jorg Beinemann +1 位作者 Karl Schaller Heinz-Otto Peitgen 《Surgical Science》 2014年第10期439-443,共5页
Background: Three-dimensional printing (3DP) technologies are a trendsetting topic, also in the field of surgery. Preoperative planning for maxillofacial and neurological surgery, for instance, increasingly involves s... Background: Three-dimensional printing (3DP) technologies are a trendsetting topic, also in the field of surgery. Preoperative planning for maxillofacial and neurological surgery, for instance, increasingly involves skull models obtained by 3DP. However, the cranial replicas currently used in this context have been shown to not reproduce the exact anatomy of the individual patient undergoing surgery. Objective: The present study aimed at investigating the extent to which manual editing, using current computer software tools, can improve skull models derived from medical images. Methods: Skull computed tomography (CT) was obtained on three cadavers and?sent to three institutions that provide preoperative 3DP services. Each institute independently?performed 3D reconstructions, including routine manual editing, and subsequently produced the replicas. The models were then qualitatively compared with the respective original skull. For?quantitative comparison surface scans of particular regions of interest were made and the deviations assessed using 3-matic software (Materialise, Leuven, Belgium). Results: Routine manual editing of CT images resulted in replicas that were clear improvements over automatically generated reconstructions. This was particularly the case for teeth artefacts and thin-walled entities (e.g. paranasal sinuses). Conversely, however, many anatomical structures remained incorrectly rendered (e.g. orbitae, pterygoid processes, and sella turcica). Extraosseous calcifications had regularly not been removed. After extensive manual editing, however, replicas were able to provide largely submillimeter accuracy (mean deviation 0.2496 mm;standard deviation ±0.2276 mm). Conclusions: This study confirms that manual editing with current computer science tools does improve the quality of CT-based 3D printed skull models. But, it also demonstrates that a number of structures remain largely incorrectly rendered when edited in the presently used surgical framework. Conversely, it shows that highly accurate replicas are feasible, provided that extensive manual editing is performed. 展开更多
关键词 Preoperative Replicas 3D Printing SKULL MODELS Accuracy
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A Mathematical Model for the Effect of Enzymes on Metabolism of Pharmacologically Active Substances
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作者 Donald A. Drew 《Applied Mathematics》 2021年第1期1-17,共17页
Addiction is a societal issue with many negative effects. Substances that cause addictive reactions are easily ingested and interact with some part of the neural pathway. This paper describes a mathematical model for ... Addiction is a societal issue with many negative effects. Substances that cause addictive reactions are easily ingested and interact with some part of the neural pathway. This paper describes a mathematical model for the systemic level of a substance subject to degradation (via metabolism) and reversible binding to psychoactive sites. The model allows the determination of bound substance levels during the processing of a dose, and how the maximum level depends on system parameters. The model also allows the study of a particular periodic repetitive dosing described by a rapid ingestion if a dose is at constant intervals. 展开更多
关键词 Mathematical Model ADDICTION METABOLISM
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Well-Posedness and a Finite Difference Approximation for a Mathematical Model of HPV-Induced Cervical Cancer
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作者 Baoling Ma Jeremy J. Thibodeaux 《Applied Mathematics》 2023年第3期151-172,共22页
We present a first-order finite difference scheme for approximating solutions of a mathematical model of cervical cancer induced by the human papillomavirus (HPV), which consists of four nonlinear partial differential... We present a first-order finite difference scheme for approximating solutions of a mathematical model of cervical cancer induced by the human papillomavirus (HPV), which consists of four nonlinear partial differential equations and a nonlinear first-order ordinary differential equation. The scheme is analyzed and used to provide an existence-uniqueness result. Numerical simulations are performed in order to demonstrate the first-order rate of convergence. A sensitivity analysis was done in order to compare the effects of two drug types, those that increase the death rate of HPV-infected cells, and those that increase the death rate of the precancerous cell population. The model predicts that treatments that affect the precancerous cell population by directly increasing the corresponding death rate are far more effective than those that increase the death rate of HPV-infected cells. 展开更多
关键词 Age Structured Cervical Cancer Finite Difference Human Papillomavirus Mathematical Model
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A Mathematical Modeling of 3D Cubical Geometry Hypothetical Reservoir under the Effect of Nanoparticles Flow Rate,Porosity,and Relative Permeability
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作者 Mudasar Zafar Hamzah Sakidin +6 位作者 Abida Hussain Loshini Thiruchelvam Mikhail Sheremet Iskandar Dzulkarnain Roslinda Nazar Abdullah Al-Yaari Rizwan Safdar 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第11期1193-1211,共19页
This study aims to formulate a steady-state mathematical model for a three-dimensional permeable enclosure(cavity)to determine the oil extraction rate using three distinct nanoparticles,SiO_(2),Al_(2)O_(3),and Fe_(2)O... This study aims to formulate a steady-state mathematical model for a three-dimensional permeable enclosure(cavity)to determine the oil extraction rate using three distinct nanoparticles,SiO_(2),Al_(2)O_(3),and Fe_(2)O_(3),in unconventional oil reservoirs.The simulation is conducted for different parameters of volume fractions,porosities,and mass flow rates to determine the optimal oil recovery.The impact of nanoparticles on relative permeability(kr)and water is also investigated.The simulation process utilizes the finite volume ANSYS Fluent.The study results showed that when the mass flow rate at the inlet is low,oil recovery goes up.In addition,they indicated that silicon nanoparticles are better at getting oil out of the ground(i.e.,oil reservoir)than Al_(2)O_(3)and Fe_(2)O_(3).Most oil can be extracted from SiO_(2),Al_(2)O_(3),and Fe_(2)O_(3)at a rate of 97.8%,96.5%,and 88%,respectively. 展开更多
关键词 Unconventional reservoir cubical cavity oil recovery rate reservoir engineering mathematical modeling
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Demand Forecasting Tool Driving the Digital Twin of a Perishable Food Process
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作者 Laura Lucantoni Stefano Croci +3 位作者 Giovanni Mazzuto Filippo Emanuele Ciarapica Maurizio Bevilacqua Severino Perenzoni 《IEEE/CAA Journal of Automatica Sinica》 2025年第11期2356-2358,共3页
Dear Editor,The food industry emphasizes improving demand forecasting to align production with consumer needs and reduce waste.This letter thus presents a study that integrates artificial intelligence(AI)and digital t... Dear Editor,The food industry emphasizes improving demand forecasting to align production with consumer needs and reduce waste.This letter thus presents a study that integrates artificial intelligence(AI)and digital twin(DT)technologies to enhance decision-making and efficiency in food production.A data-driven DT was implemented in an Italian company for Raspberry production planning,based on a daily demand forecasting tool powered by a dynamic extreme gradient boosting(XGBoost)algorithm.The model achieved a mean absolute percentage error(MAPE)of 16.37%with 1.69 average of absolute extra working hours(AEW)and a tracking signal(TS)range of[−1.9,+4.3]. 展开更多
关键词 improving demand forecasting demand forecasting daily demand forecasting tool dynamic extreme gradient artificial intelligence artificial intelligence ai align production digital twin dt technologies
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Study of the Boundary Pressure Instability of the SPH Method Based on Fan-Free Surface Detection
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作者 ZHAO Jie ZHENG Xiong-bo +2 位作者 MU Tong-yao LENG Yue-yue ZHAO Hao-yu 《China Ocean Engineering》 2025年第2期340-353,共14页
The weakly compressible smooth particle hydrodynamics(WCSPH)model is studied to address the boundary pressure instability of the SPH method,resulting in the development of the SPH method with improved dynamic boundary... The weakly compressible smooth particle hydrodynamics(WCSPH)model is studied to address the boundary pressure instability of the SPH method,resulting in the development of the SPH method with improved dynamic boundary conditions.This method employs the‘fan’search method for free surface detection,effectively identifying cavity interface particles with diameters smaller than the support domain’s radius,thereby indirectly enhancing the algorithm’s accuracy.On this basis,an improved dynamic boundary condition is proposed by updating the boundary particle pressure calculation scheme to achieve a more stable and continuous pressure field,thereby effectively preventing particles from penetrating the boundary.The SPH method with improved dynamic boundary conditions is used to simulate typical high-speed impact problems such as wedge entry and dam break.The simulation results are in good agreement with the experimental data and other numerical results. 展开更多
关键词 smoothed particle hydrodynamics(SPH) free surface detection improved dynamic boundary highspeed impact
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