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Numerical Treatments for a Crossover Cholera Mathematical Model Combining Different Fractional Derivatives Based on Nonsingular and Singular Kernels
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作者 Seham M.AL-Mekhlafi Kamal R.Raslan +2 位作者 Khalid K.Ali Sadam.H.Alssad Nehaya R.Alsenaideh 《Computer Modeling in Engineering & Sciences》 2025年第5期1927-1953,共27页
This study introduces a novel mathematical model to describe the progression of cholera by integrating fractional derivatives with both singular and non-singular kernels alongside stochastic differential equations ove... This study introduces a novel mathematical model to describe the progression of cholera by integrating fractional derivatives with both singular and non-singular kernels alongside stochastic differential equations over four distinct time intervals.The model incorporates three key fractional derivatives:the Caputo-Fabrizio fractional derivative with a non-singular kernel,the Caputo proportional constant fractional derivative with a singular kernel,and the Atangana-Baleanu fractional derivative with a non-singular kernel.We analyze the stability of the core model and apply various numerical methods to approximate the proposed crossover model.To achieve this,the approximation of Caputo proportional constant fractional derivative with Grünwald-Letnikov nonstandard finite difference method is used for the deterministic model with a singular kernel,while the Toufik-Atangana method is employed for models involving a non-singular Mittag-Leffler kernel.Additionally,the integral Caputo-Fabrizio approximation and a two-step Lagrange polynomial are utilized to approximate the model with a non-singular exponential decay kernel.For the stochastic component,the Milstein method is implemented to approximate the stochastic differential equations.The stability and effectiveness of the proposed model and methodologies are validated through numerical simulations and comparisons with real-world cholera data from Yemen.The results confirm the reliability and practical applicability of the model,providing strong theoretical and empirical support for the approach. 展开更多
关键词 Cholera crossover model Caputo proportional constant fractional derivative Caputo-Fabrizio
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Nonlinear Post-Buckling Stability of Graphene Origami-Enabled Auxetic Metamaterials Plates
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作者 Salwa A.Mohamed Mohamed A.Eltaher +1 位作者 Nazira Mohamed Rasha Abo-bakr 《Computer Modeling in Engineering & Sciences》 2025年第4期515-538,共24页
The nonlinear post-buckling response of functionally graded(FG)copper matrix plates enforced by graphene origami auxetic metamaterials(GOAMs)is investigated in the currentwork.The auxeticmaterial properties of the pla... The nonlinear post-buckling response of functionally graded(FG)copper matrix plates enforced by graphene origami auxetic metamaterials(GOAMs)is investigated in the currentwork.The auxeticmaterial properties of the plate are controlled by graphene content and the degree of origami folding,which are graded across the thickness of the plate.Thematerial properties of the GOAM plate are evaluated using genetic micro-mechanicalmodels.Governing nonlinear eigenvalue problems for the post-buckling response of the GOAM composite plate are derived using the virtual work principle and a four-variable nonlinear shear deformation theory.A novel differential quadrature method(DQM)algorithm is developed to solve the nonlinear eigenvalue problem.Detailed parametric studies are presented to explore the effects of graphene content,folding degree,and GO distribution patterns on the post-buckling responses of GOAM plates.Results show that high tunability in post-buckling characteristics can be achieved by using GOAM.FunctionallyGradedGraphene OrigamiAuxeticMetamaterials(FG-GOAM)plates can be used in aerospace structures to improve their structural performance and response. 展开更多
关键词 POSTBUCKLING nonlinear stability auxetic metamaterials higher order plate DQM numerical solution
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Neural network analysis for prediction of heat transfer of aqueous hybrid nanofluid flow in a variable porous space with varying film thickness over a stretched surface
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作者 Abeer S Alnahdi Taza Gul 《Chinese Physics B》 2025年第2期316-326,共11页
The high thermal conductivity of the nanoparticles in hybrid nanofluids results in enhanced thermal conductivity associated with their base fluids.Enhanced heat transfer is a result of this high thermal conductivity,w... The high thermal conductivity of the nanoparticles in hybrid nanofluids results in enhanced thermal conductivity associated with their base fluids.Enhanced heat transfer is a result of this high thermal conductivity,which has significant applications in heat exchangers and engineering devices.To optimize heat transfer,a liquid film of Cu and TiO_(2)hybrid nanofluid behind a stretching sheet in a variable porous medium is being considered due to its importance.The nature of the fluid is considered time-dependent and the thickness of the liquid film is measured variable adjustable with the variable porous space and favorable for the uniform flow of the liquid film.The solution of the problem is acquired using the homotopy analysis method HAM,and the artificial neural network ANN is applied to obtain detailed information in the form of error estimation and validations using the fitting curve analysis.HAM data is utilized to train the ANN in this study,which uses Cu and TiO_(2)hybrid nanofluids in a variable porous space for unsteady thin film flow,and it is used to train the ANN.The results indicate that Cu and TiO_(2)play a greater role in boosting the rate. 展开更多
关键词 thin film of Cu and TiO_(2)hybrid nanofluids variable porous space unsteady stretching sheet viscous dissipation heat transfer optimization artificial neural network
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A New Extension Odd Generalized Exponential Model Using Type-Ⅱ Progressive Censoring and Its Applications in Engineering and Medicine
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作者 Zohra A.Esaadi Rabab S.Gomaa +2 位作者 Beih S.El-Desouky Ehab M.Almetwally Alia M.Magar 《Computer Modeling in Engineering & Sciences》 2025年第8期2063-2097,共35页
A new extended distribution called the Odd Exponential Generalized Exponential-Exponential distribution(EOEGE-E)is proposed based on generalization of the odd generalized exponential family(OEGE-E).The statistical pro... A new extended distribution called the Odd Exponential Generalized Exponential-Exponential distribution(EOEGE-E)is proposed based on generalization of the odd generalized exponential family(OEGE-E).The statistical properties of the proposed distribution are derived.The study evaluates the accuracy of six estimation methods under complete samples.Estimation techniques include maximumlikelihood,ordinary least squares,weighted least squares,maximumproduct of spacing,Cramer vonMises,and Anderson-Darling methods.Twomethods of estimation for the involved parameters are considered based on progressively type Ⅱ censored data(PTⅡC).These methods are maximum likelihood and maximum product of spacing.The proposed distribution’s effectiveness was evaluated using different data sets from various fields.The proposed distribution provides a better fit for these datasets than existing probability distributions. 展开更多
关键词 Odd generalized exponential distribution likelihood and product of spacing progressive censoring progressive typeⅡcensoring
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Do energy patents and energy prices drive the shift toward sustainable energy sources? A wavelet quantile-based analysis
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作者 T.S.Adebayo V.O.Olanrewaju B.Uzun 《Geoscience Frontiers》 2025年第5期299-312,共14页
While the significant role of technological innovation in promoting renewable energy has been extensively explored in the literature,limited attention has been paid to the impact of energy patents,particularly clean e... While the significant role of technological innovation in promoting renewable energy has been extensively explored in the literature,limited attention has been paid to the impact of energy patents,particularly clean energy patents and fossil fuel patents.This study pioneers an investigation into the effects of energy patents and energy prices on renewable energy consumption.The study utilizes data from 2000Q1 to 2023Q4 and,due to the nonlinear nature of the series,applies wavelet quantile-based methods.Specifically,it introduces the wavelet quantile cointegration approach to evaluate cointegration across different quantiles and time horizons,along with the wavelet quantile-on-quantile regression method.The results confirm cointegration across different periods and quantiles,highlighting the significant relationships between energy patents,economic factors,and renewable energy consumption.Furthermore,we found that fossil energy patents negatively affect renewable energy consumption,while clean energy patents have a similar but weaker effect,especially in the short term.In addition,higher energy prices promote renewable energy adoption while economic growth positively influences renewable energy consumption,particularly in the short term.The study formulates specific policies based on these findings. 展开更多
关键词 Energy price Clean energy patents Fossil fuel patents Renewable energy consumption Environmental sustainability
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Parameters Estimation of Modified Triple Diode Model of PSCs Considering Charge Accumulations and Electric Field Effects Using Puma Optimizer
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作者 Amlak Abaza Ragab A.El-Sehiemy +1 位作者 Mona Gafar Ahmed Bayoumi 《Computer Modeling in Engineering & Sciences》 2025年第4期723-745,共23页
Promoting the high penetration of renewable energies like photovoltaic(PV)systems has become an urgent issue for expanding modern power grids and has accomplished several challenges compared to existing distribution g... Promoting the high penetration of renewable energies like photovoltaic(PV)systems has become an urgent issue for expanding modern power grids and has accomplished several challenges compared to existing distribution grids.This study measures the effectiveness of the Puma optimizer(PO)algorithm in parameter estimation of PSC(perovskite solar cells)dynamic models with hysteresis consideration considering the electric field effects on operation.The models used in this study will incorporate hysteresis effects to capture the time-dependent behavior of PSCs accurately.The PO optimizes the proposed modified triple diode model(TDM)with a variable voltage capacitor and resistances(VVCARs)considering the hysteresis behavior.The suggested PO algorithm contrasts with other wellknown optimizers from the literature to demonstrate its superiority.The results emphasize that the PO realizes a lower RMSE(Root mean square errors),which proves its capability and efficacy in parameter extraction for the models.The statistical results emphasize the efficiency and supremacy of the proposed PO compared to the other well-known competing optimizers.The convergence rates show good,fast,and stable convergence rates with lower RMSE via PO compared to the other five competitive optimizers.Moreover,the lowermean realized via the PO optimizer is illustrated by the box plot for all optimizers. 展开更多
关键词 Dynamic model of PSCs puma optimizer parameter estimation triple diode model
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Displacement Feature Mapping for Vehicle License Plate Recognition Influenced by Haze Weather
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作者 Mohammed Albekairi Radhia Khdhir +3 位作者 Amina Magdich Somia Asklany Ghulam Abbas Amr Yousef 《Computer Modeling in Engineering & Sciences》 2025年第9期3607-3644,共38页
License plate recognition in haze-affected images is challenging due to feature distortions such as blurring and elongation,which lead to pixel displacements.This article introduces a Displacement Region Recognition M... License plate recognition in haze-affected images is challenging due to feature distortions such as blurring and elongation,which lead to pixel displacements.This article introduces a Displacement Region Recognition Method(DR2M)to address such a problem.This method operates on displaced features compared to the training input observed throughout definite time frames.The technique focuses on detecting features that remain relatively stable under haze,using a frame-based analysis to isolate edges minimally affected by visual noise.The edge detection failures are identified using a bilateral neural network through displaced feature training.The training converges bilaterally towards the minimum edges from the maximum region.Thus,the training input and detected edges are used to identify the displacement between observed image frames to extract and differentiate the license plate region from the other vehicle regions.The proposed method maps the similarity feature between the detected and identified vehicle regions.This aids in leveraging the plate recognition precision with a high F1 score.Thus,this technique achieves a 10.27%improvement in identification precision,a 10.57%increase in F1 score,and a 9.73%reduction in false positive rate compared to baseline methods under maximum displacement conditions caused by haze.The technique attains an identification precision of 95.68%,an F1 score of 94.68%,and a false positive rate of 4.32%,indicating robust performance under haze-affected settings. 展开更多
关键词 Neural network machine learning edge detection feature displacement haze weather
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Computational Modeling to Predict Conservative Treatment Outcome for Patients with Plaque Erosion:An OCT-Based Patient-Specific FSI Modeling Study
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作者 Yanwen Zhu Chen Zhao +13 位作者 Yishuo Xu Zheyang Wu Akiko Maehara Liang Wang Dirui Zhang Ming Zeng Rui Lv Xiaoya Guo Mengde Huang Minglong Chen Gary S.Mintz Dalin Tang Haibo Jia Bo Yu 《Computer Modeling in Engineering & Sciences》 2025年第8期1249-1270,共22页
Image-based computational models have been used for vulnerable plaque progression and rupture predictions,and good results have been reported.However,mechanisms and predictions for plaque erosion are underinvestigated... Image-based computational models have been used for vulnerable plaque progression and rupture predictions,and good results have been reported.However,mechanisms and predictions for plaque erosion are underinvestigated.Patient-specific fluid-structure interaction(FSI)models based on optical coherence tomography(OCT)follow-up data from patients with plaque erosion and who received conservative antithrombotic treatment(using medication,no stenting)to identify risk factors that could be used to predict the treatment outcome.OCT and angiography datawere obtained from10 patientswho received conservative antithrombotic treatment.Five participants had worse outcomes(WOG,stenosis severity≥70%at one-year follow-up),while the other five had better outcomes(BOG,stenosis severity<70%at one-year follow-up).Patient-specific 3D FSI models were constructed to obtain morphological and biomechanical risk factor values(a total of nine risk factors)for comparison and prediction.A logistic regressionmodel was used to identify optimal predictors with the best treatment outcome prediction accuracies.Our results indicated that the combination of wall shear stress(WSS),lipid percent,and thrombus burden was the best group predictor according to the mean area under the curve(AUC)of 0.96(90%confidence interval=(0.85,1.00)).WSS was the best single predictor withmean AUC=0.70(90%confidence interval=(0.20,1.00)).Thrombus burden was the only risk factor showing statistically significant group difference,suggesting its crucial role in the outcomes of conservative anti-thrombotic therapy.This pilot study indicated that integratingmorphological and biomechanical risk factors could improve treatment outcome prediction accuracy in patients with plaque erosion compared to predictions using single predictors.Large-scale patient studies are needed to further validate our findings. 展开更多
关键词 Plaque erosion fluid-structure interaction optical coherence tomography wall shear stress antithrombotic therapy
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Propagation of traveling wave solutions to the Vakhnenko-Parkes dynamical equation via modified mathematical methods
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作者 Aly R.Seadawy Asghar Ali +1 位作者 Wafaa A.Albarakati Dumitru Baleanu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2022年第1期21-34,共14页
In this paper, we investigate some new traveling wave solutions to Vakhnenko-Parkes equation via three modified mathematical methods. The derived solutions have been obtained including periodic and solitons solutions ... In this paper, we investigate some new traveling wave solutions to Vakhnenko-Parkes equation via three modified mathematical methods. The derived solutions have been obtained including periodic and solitons solutions in the form of trigonometric, hyperbolic, and rational function solutions. The graphical representations of some solutions by assigning particular values to the parameters under prescribed conditions in each solutions and comparing of solutions with those gained by other authors indicate that these employed techniques are more effective, efficient and applicable mathematical tools for solving nonlinear problems in applied science. 展开更多
关键词 Vakhnenko-Parkes equation(VPE) generalized direct algebraic method extended simple equation method modified F-expansion method
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Exact Traveling Wave Solutions of Nonlinear PDEs in Mathematical Physics
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作者 Jameel F. Alzaidy 《Applied Mathematics》 2012年第7期738-745,共8页
In the present article, we construct the exact traveling wave solutions of nonlinear PDEs in mathematical physics via the variant Boussinesq equations and the coupled KdV equations by using the extended mapping method... In the present article, we construct the exact traveling wave solutions of nonlinear PDEs in mathematical physics via the variant Boussinesq equations and the coupled KdV equations by using the extended mapping method and auxiliary equation method. This method is more powerful and will be used in further works to establish more entirely new solutions for other kinds of nonlinear partial differential equations arising in mathematical physics. 展开更多
关键词 Extended Mapping METHOD Auxiliary Equation METHOD The VARIANT BOUSSINESQ EQUATIONS The Coupled KDV EQUATIONS TRAVELING Wave Solutions
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The matrix representation for the mathematic structure of Shannon’s information measures
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作者 苑延华 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第2期232-235,共4页
Shannon’s information measure is a crucial concept in Information Theory. And the research, for the mathematics structure of Shannon’s information measure, is to recognize the essence of information measure. The lin... Shannon’s information measure is a crucial concept in Information Theory. And the research, for the mathematics structure of Shannon’s information measure, is to recognize the essence of information measure. The linear relation between Shannon’s information measures and some signed measure space by using the formal symbols substitution rule is discussed. Furthermore, the coefficient matrix recurrent formula of the linear relation is obtained. Then the coefficient matrix is proved to be invertible via mathematical induction. This shows that the linear relation is one-to-one, and according to this, it can be concluded that a compact space can be generated from Shannon’s information measures. 展开更多
关键词 ENTROPY Shannon's information measures signed measure the recurrent formula of l-measure matrix
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Dispersive propagation of optical solitions and solitary wave solutions of Kundu-Eckhaus dynamical equation via modified mathematical method
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作者 Aly R.Seadawy Mujahid Iqbal 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第1期16-26,共11页
In this research work,we constructed the optical soliton solutions of nonlinear complex Kundu-Eckhaus(KE)equation with the help of modified mathematical method.We obtained the solutions in the form of dark solitons,br... In this research work,we constructed the optical soliton solutions of nonlinear complex Kundu-Eckhaus(KE)equation with the help of modified mathematical method.We obtained the solutions in the form of dark solitons,bright solitons and combined dark-bright solitons,travelling wave and periodic wave solutions with general coefficients.In our knowledge earlier reported results of the KE equation with specific coefficients.These obtained solutions are more useful in the development of optical fibers,dynamics of solitons,dynamics of adiabatic parameters,dynamics of fluid,problems of biomedical,industrial phenomena and many other branches.All calculations show that this technique is more powerful,effective,straightforward,and fruitfulness to study analytically other higher-order nonlinear complex PDEs involves in mathematical physics,quantum physics,Geo physics,fluid mechanics,hydrodynamics,mathematical biology,field of engineering and many other physical sciences. 展开更多
关键词 Kundu-Eckhaus equation modified mathematical method solitons and solitary wave solutions
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Mathematical Modelling of Quantum Kernel Method for Biomedical Data Analysis
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作者 Mahmoud Ragab Ehab Bahauden Ashary +2 位作者 Maha Farouk S.Sabir Adel A.Bahaddad Romany F.Mansour 《Computers, Materials & Continua》 SCIE EI 2022年第6期5441-5457,共17页
This study presents a novelmethod to detect themedical application based on Quantum Computing(QC)and a few Machine Learning(ML)systems.QC has a primary advantage i.e.,it uses the impact of quantum parallelism to provi... This study presents a novelmethod to detect themedical application based on Quantum Computing(QC)and a few Machine Learning(ML)systems.QC has a primary advantage i.e.,it uses the impact of quantum parallelism to provide the consequences of prime factorization issue in a matter of seconds.So,this model is suggested for medical application only by recent researchers.A novel strategy i.e.,Quantum KernelMethod(QKM)is proposed in this paper for data prediction.In this QKM process,Linear Tunicate Swarm Algorithm(LTSA),the optimization technique is used to calculate the loss function initially and is aimed at medical data.The output of optimization is either 0 or 1 i.e.,odd or even in QC.From this output value,the data is identified according to the class.Meanwhile,the method also reduces time,saves cost and improves the efficiency by feature selection process i.e.,Filter method.After the features are extracted,QKM is deployed as a classification model,while the loss function is minimized by LTSA.The motivation of the minimal objective is to remain faster.However,some computations can be performed more efficiently by the proposed model.In testing,the test data was evaluated by minimal loss function.The outcomes were assessed in terms of accuracy,computational time,and so on.For this,databases like Lymphography,Dermatology,and Arrhythmia were used. 展开更多
关键词 Medical data classification feature selection qkm classifier ltsa optimization
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A Mathematical Model for Pulsating Flow of Ionic Fluid under an Axial Electric Field: EMF Effect on Blood Flow
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作者 Mona A. EI-Naggar Medhat A. Messiery 《Journal of Physical Science and Application》 2012年第4期61-70,共10页
The present work introduces a mathematical model for ionic fluid that flows under the effect of both pulsating pressure and axial electromagnetic field. The fluid is treated as a Newtonian fluid applying Navier-Stokes... The present work introduces a mathematical model for ionic fluid that flows under the effect of both pulsating pressure and axial electromagnetic field. The fluid is treated as a Newtonian fluid applying Navier-Stokes equation. The fluid is considered as a neutral mixture of positive and negative ions. The effect of axial electric field is investigated to determine velocity profiles. Hydroelectric equation of the flow is deduced under dc and ac external electric field. Hence the effect of applied frequency (0-1 GHz) and amplitude (10-350 V/m) is illustrated. The ultimate goal is to approach the problem of EMF field interaction with blood flow. The applied pressure waveform is represented as such to simulate the systolic-diastolic behavior. Simulation was carried out using Maple software using blood plasma parameters; hence velocity profiles under various conditions are reported. 展开更多
关键词 Newtonian fluid navier-stokes ionic fluid blood flow electric field hydroelectric flow simulation velocity profiles EMF bioeffects.
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The Future of Snapchat: A Mathematical Model
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作者 Salma M. Al-Tuwairqi Bushra K. Aloosh Rana A. Bagies 《Journal of Applied Mathematics and Physics》 2019年第4期841-860,共20页
Saudi Arabia has become one of the leading top five countries based on the number of Snapchat users as of October 2018. In this project, we build a novel mathematical model to explore the future of Snapchat in general... Saudi Arabia has become one of the leading top five countries based on the number of Snapchat users as of October 2018. In this project, we build a novel mathematical model to explore the future of Snapchat in general and in Saudi Arabia particularly. The model incorporates the trend of “famous Snapchatters” that is highly observed in Saudi Arabia. The model is governed by a system of nonlinear differential equations. We analyze the system qualitatively and numerically. As a result, three equilibrium points are obtained. By considering their stability, we outline different possible scenarios for the future of Snapchat. Moreover, parameter analysis is performed to investigate key parameters in the model. Furthermore, an online survey is conducted to estimate the values for the parameters in the model to explore which scenario is likely to happen in Saudi Arabia. 展开更多
关键词 MATHEMATICAL MODEL STABILITY Snapchat SAUDI ARABIA
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An object-oriented approach to teaching mathematics for engineering and science students
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作者 Alexander Y. Vaninsky 《通讯和计算机(中英文版)》 2009年第11期77-84,共8页
关键词 面向对象编程 数学教学 学生 工程 科学 数学相关 数学专业 数据类型
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Pre-service Early Childhood Teachers’ Attitude Towards Mathematics: A Jamaican Inquiry
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作者 Corey Williamson Shaneille Samuels Rayan McIntosh Henry 《Psychology Research》 2021年第1期18-27,共10页
The purpose of the study was to evaluate Jamaican early childhood pre-service teachers’attitudes towards mathematics.The study is designed according to the quantitative survey model in the descriptive type.In this st... The purpose of the study was to evaluate Jamaican early childhood pre-service teachers’attitudes towards mathematics.The study is designed according to the quantitative survey model in the descriptive type.In this study,a modified version of the Fennema-Sherman mathematics attitude scale was used to measure the mathematics attitude of 144 early childhood pre-service teachers in four different categories of the attitude scale(mathematics usefulness,confidence in learning mathematics,mathematics anxiety,and mathematics motivation).The data were collected from participants in the five teachers’colleges that offer the early childhood education program in Jamaica.The findings revealed that Jamaican early childhood pre-service teachers generally have a more positive attitude towards mathematics.A comparison among the different year groups revealed that a significantly greater percentage of the Year two group of participants possessed a more positive mathematics attitude than the other year groups.A significantly higher percentage of the Year three group indicated that they do not want to teach the subject in the future.The findings have implications for the teaching and learning of mathematics in the early childhood education program in Jamaica and,by extension,the teaching and learning of mathematics at the early childhood level of the education system. 展开更多
关键词 attitude towards mathematics early childhood pre-service teachers mathematics attitude scales
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Mathematical Analysis of Control Strategies of HCV in a Community with Inflow of Infected Immigrants
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作者 Neterindwa Ainea Estomih S. Massawe +1 位作者 Oluwole Daniel Makinde Lucy Namkinga 《Advances in Infectious Diseases》 2015年第1期1-13,共13页
In this paper, we derive and analyse rigorously a mathematical model of control strategies (screening, education, health care and immunization) of HCV in a community with inflow of infected immigrants. Both qualitativ... In this paper, we derive and analyse rigorously a mathematical model of control strategies (screening, education, health care and immunization) of HCV in a community with inflow of infected immigrants. Both qualitative and quantitative analysis of the model is performed with respect to stability of the disease free and endemic equilibria. The results show that the disease free equilibrium is locally stable at threshold parameter less than unity and unstable at threshold parameter greater than unity. Using Lyapunov method, endemic equilibrium is globally stable under certain conditions. Numerical simulation of the model is implemented to investigate the sensitivity of certain key parameters on the HCV model in a community with inflow of infected immigrants. However, analysis shows that screening, education, health care and immunization have the effect of reducing the transmission of the disease in the community. 展开更多
关键词 HCV Disease INFECTED IMMIGRANTS Stability Sensitivity Index LYAPUNOV Method Screening Education Health Care and IMMUNIZATION
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Mathematical analysis of drug resistance in vertical transmission of HIV/AIDS
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作者 Symon Chibaya Moatlhodi Kgosimore Estomih S. Massawe 《Open Journal of Epidemiology》 2013年第3期139-148,共10页
A nonlinear mathematical model of vertical transmission of HIV/AIDS is proposed to study the effects of drug resistance in the spread of the disease. The study assumes that treatment leads to the evolution of drug res... A nonlinear mathematical model of vertical transmission of HIV/AIDS is proposed to study the effects of drug resistance in the spread of the disease. The study assumes that treatment leads to the evolution of drug resistance in some pockets of the population. We use traditional methods to determine conditions for existence and stability of disease-free and endemic equilibrium points of the model. The study showed that the burden of the disease may be reduced if the reproduction number is reduced below unity and may persist if the reproduction number is raised above unity. Furthermore, evolution of drug resistance due to treatment may change the cause of the epidemic. 展开更多
关键词 Dynamics of HIV/AIDS VERTICAL TRANSMISSION DRUG RESISTANCE
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Mathematics Knowledge of Proof in Geometry: Pre-Service Teachers' Perspectives
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作者 Jayaluxmi Naidoo Bongani Ndlovu 《Journal of Mathematics and System Science》 2014年第12期769-780,共12页
This article is based on research on pre-service teachers' perspectives on their mathematics knowledge of proof in geometry. The study was framed using tile mathematical knowledge for teaching framework. This qualita... This article is based on research on pre-service teachers' perspectives on their mathematics knowledge of proof in geometry. The study was framed using tile mathematical knowledge for teaching framework. This qualitative study employed the use of a task-based worksheet, focus group sessions and semi-structured individual interviews. The task-based worksheet was completed by 180 pre-service mathematics teachers (second, third and fourth year mathematics education students). Pre-service mathematics teachers are student teachers who have not yet completed their training to become teachers. After the analysis of the task-based worksheet, 20 participants were invited to participate in focus group sessions and individual interviews. The findings of the study reveal that the participants possess peripheral mathematics knowledge of proof in geometry. The study aims at assisting pre-service teachers and interested educationists to explore innovative methods of acquiring and imparting mathematics knowledge of proof in geometry. The study proposes possible changes in curriculum at school and university level. 展开更多
关键词 GEOMETRY KNOWLEDGE MATHEMATICS pedagogical content knowledge pre-service teacher PROOF
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