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The Effect of Non-Contact Conditions in a Splinted Fixed Partial Denture on the Load Sharing mechanism： A Finite Element Study

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Journal of Bionic Engineering 2012年第3期9卷 336-342页

作者： m. Z. Bendjaballah Biomedical Technology Department College of Applied Medical Sciences King Saud University Riyadh Saudi Arabia

A computer-aided design model for a fixed partial denture was constructed and used in a finite element analysis to study the overall load sharing mechanism between the fixed partial denture and oral structures while the denture base rested on the al- veolar ridge. To investigate the consequences of non-contact conditions, three additional models were generated incorporating a uniform clearance of 0.125 mm, 0.25 mm, and 0.5 mm, respectively. A 100 N static load located at the free end of the prosthesis was applied while the distal portion of the jaw was set fixed. The results show that whilst releasing the ridge almost entirely, the presence of the clearance drastically increased the load on the splinting teeth. A pull-out force on the canine tooth of about 44 N was computed, accompanied by a mesio-distal moment of about 500 ***. The combination of which was similar to the tooth extraction maneuver performed by the dentist. In contrast, the second premolar was found to bear a push-in force of almost 115 N. The first molar, though barely solicited in the contact condition, became substantially loaded in non-contact conditions, which validates the choice of sacrificing three teeth to support the denture.

关键词： finite element analysis splinted fixed partial denture hygienic space load transfer mechanism contact problem

Analysis of Functionally Graded Piezoelectric Cylinders in a Hygrothermal Environment

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Advances in Applied mathematics and mechanics 2014年第2期6卷 233-246页

作者： m.N.m.Allam A.m.Zenkour R.Tantawy Department of mathematics Faculty of ScienceMansoura UniversityMansoura 35516Egypt Department of mathematics Faculty of ScienceKing Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia Department of mathematics Faculty of ScienceKafrelsheikh UniversityKafr El-Sheikh 33516Egypt Department of mathematics Faculty of ScienceDamietta University34517Egypt

This paper presents an analytical solution for the interaction of electric potentials,electric displacement,elastic deformations,and describes hygrothermal effect responses in hollow and solid cylinders,subjected to mechanical load and electric *** solutions for displacement,stresses and electric potentials in functionally graded piezoelectric material are determined using the infinitesimal *** material properties coefficients of the present cylinder are assumed to be graded in the radial direction by a power law *** examples display the significant of influence of material *** is interesting to note that selecting a specific value of inhomogeneity parameter can optimize the piezoelectric hollow and solid cylinders responses,which will be of particular importance in modern engineering designs.

关键词： Functionally graded piezoelectric material hygrothermal effect.

magnetic,dielectric and electrical modulus of Ce^(3+) doped cobalt-magnesium ferrite nanoparticles

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Journal of Rare Earths 2024年第2期42卷 373-382,I0005页

作者： N.m.Basfer Hanaa Almaghamsi Department of Physics Umm AL-Qura UniversityMakkahSaudi Arabia Physics Department College of Science and ArtKing Abdulaziz UniversityPOB344Rabigh291Saudi Arabi

In this work,the magnetic,dielectric properties and electric modulus of Ce^(3+) substituted cobaltmagnesium(Co_(0.7)mg_(0.3)Ce_(x)Fe_(2-x)O_4)(labeled as CmCF) ferrite nanoparticles were investigated in *** magnetization decreases from 50.05 to 34.87 emu/g for further substituting Ce^(3+) ***,coercivity increases from 738.22 Gs for the CmCFO sample to 912.10 Gs for the CmCF2 sample,then decreases monotonically to 762.1 Gs for the CmCF5 *** cerium content and particle size play important roles in controlling the magnetization and coercivity of the CmCF *** CmCF nanoferrites are suitable for microwave applications since their high-frequency response ranges from 7.72 to 11.07 *** CmCF nanoferrites' dielectric parameter dispersion exhibits normal *** pristine Co-mg nanoferrite only has ε' value of 28.25,but the nanoferrite mCmF2 has ε' value of365.03,with an enhancing ratio of 1192%.The conduction mechanism of the mCmF nanoferrites was determined by fitting the σ_(ac) results via the Jonscher power *** 653 K,large polaron tunnelling is thought to be responsible for this conduction process,which is followed by electron barrier hopping at higher ***-Cole diagrams at different temperatures,assuring the contributions of the grains and their boundaries at lower temperatures(653 K) and only the grains at higher *** on our results,the CmCF nanoferrites hold magnetic and semiconducting nature,which can be used in magnetic devices and dielectrics in lower-frequencies or conductors in higher-frequencies.

关键词： Nanoferrites Rare earth ions magnetic properties Dielectric parameters Impedance spectroscopy

Newtonian heating effects in three-dimensional flow of viscoelastic fluid

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Chinese Physics B 2014年第5期23卷 373-379页

作者： A.Qayyum T.Hayat m.S.Alhuthali H.m.malaikah Department of mathematics Quaid-i-Azam University 45320Islamabad 44000Pakistan Department of mathematics Faculty of ScienceKing Abdulaziz University

A mathematical model is constructed to investigate the three-dimensional flow of a non-Newtonian fluid. An in-compressible viscoelastic fluid is used in mathematical formulation. The conjugate convective process （in which heat the transfer rate from the bounding surface with a finite capacity is proportional to the local surface temperature） in three-dimensional flow of a differential type of non-Newtonian fluid is analyzed for the first time. Series solutions for the nonlinear differential system are computed. Plots are presented for the description of emerging parameters entering into the problem. It is observed that the conjugate heating phenomenon causes an appreciable increase in the temperature at the stretching wall.

关键词： viscoelastic fluid three-dimensional flow Newtonian heating

Newtonian heating in stagnation point flow of Burgers fluid

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Applied mathematics and mechanics(English Edition) 2015年第1期36卷 61-68页

作者： T.HAYAT S.ALI m.AWAIS m.S.ALHUTHALI Department of mathematics Quaid-i-Azam University Nonlinear Analysis and Applied mathematics (NAAm) Research Group Faculty of Science King Abdulaziz University Faculty of Engineering Sciences Ghulam Ishaq Khan Institute of Engineering Sciences and Technology Department of mathematics COMSATS Institute of Information Technology

The Newtonian heating effects in the stagnation point flow of a Burgers fluid are addressed in this paper. The boundary layer flow problems are stated in the spatial domain from zero to infinity. The solution expressions for the velocity and the temperature are obtained and examined for the influential variables. The tabulated values show comparison with the previous results. It is observed that the obtained results are in good agreement with the existing results in limiting sense.

关键词： Burgers fluid Newtonian heating series solutions

A New modified Inverse Lomax Distribution: Properties, Estimation and Applications to Engineering and medical Data

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Computer modeling in Engineering & Sciences 2021年第5期127卷 621-643页

作者： Abdullah m.Almarashi Department of Statistics Faculty of ScienceKing Abdulaziz UniversityJeddah21589Saudi Arabia

In this paper,a modified form of the traditional inverse Lomax distribution is proposed and its characteristics are *** new distribution which called modified logarithmic transformed inverse Lomax distribution is generated by adding a new shape parameter based on logarithmic transformed *** contains two shape and one scale parameters and has different shapes of probability density and hazard rate *** new shape parameter increases the flexibility of the statistical properties of the traditional inverse Lomax distribution including mean,variance,skewness and *** moments,entropies,order statistics and other properties are *** methods of estimation are considered to estimate the distribution *** compare the performance of the different estimators,a simulation study is *** show the flexibility and applicability of the proposed distribution two real data sets to engineering and medical fields are *** simulation results and real data analysis showed that the Anderson-Darling estimates have the smallest mean square errors among all other ***,the analysis of the real data sets showed that the traditional inverse Lomax distribution and some of its generalizations have shortcomings in modeling engineering and medical *** proposed distribution overcomes this shortage and provides a good fit which makes it a suitable choice to model such data sets.

关键词： Inverse lomax distribution logarithmic transformed method order statistics maximum likelihood estimation maximum product of spacing manuscript preparation typeset format

Physical aspects of magnetized Jeffrey nanomaterial flow with irreversibility analysis

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Chinese Physics B 2022年第8期31卷 485-493页

作者： Fazal Haq muhammad Ijaz Khan Sami Ullah Khan Khadijah m Abualnaja m A El-Shorbagy Department of mathematics Karakoram International University Main CampusGilgit 15100Pakistan Department of mathematics and Statistics Riphah International University I-14Islamabad 44000Pakistan Department of mechanics and Engineering Science Peking UniversityBeijing 100871China Department of mathematics COMSATS University IslamabadSahiwal 57000Pakistan Department of mathematics and Statistics College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of mathematics College of Science and Humanities in Al-KharjPrince Sattam bin Abdulaziz UniversityAl-Kharj 11942Saudi Arabia Department of Basic Engineering Science Faculty of EngineeringMenoufia UniversityShebin El-Kom 32511Egypt

This research presents the applications of entropy generation phenomenon in incompressible flow of Jeffrey nanofluid in the presence of distinct thermal features. The novel aspects of various features, such as Joule heating, porous medium,dissipation features, and radiative mechanism are addressed. In order to improve thermal transportation systems based on nanomaterials, convective boundary conditions are introduced. The thermal viscoelastic nanofluid model is expressed in terms of differential equations. The problem is presented via nonlinear differential equations for which analytical expressions are obtained by using the homotopy analysis method(HAm). The accuracy of solution is ensured. The effective outcomes of all physical parameters associated with the flow model are carefully examined and underlined through various curves. The observations summarized from current analysis reveal that the presence of a permeability parameter offers resistance to the flow. A monotonic decrement in local Nusselt number is noted with Hartmann number and Prandtl ***, entropy generation and Bejan number increases with radiation parameter and fluid parameter.

关键词： Jeffrey nonmaterial entropy generation magnetohydrodynamics(mHD) Bejan number porous medium Brownian motion

mHD stagnation point flow by a permeable stretching cylinder with Soret-Dufour effects

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Journal of Central South University 2015年第2期22卷 707-716页

作者： m.Ramzan m.Farooq T.Hayat A.Alsaedi J.Cao Department of mathematics Faculty of Computing Mohammad Ali Jinnah UniversityIslamabad Campus 44000 Pakistan Department of mathematics Quaid-I-Azam University 45320 Islamabad 44000 Pakistan Nonlinear Analysis and Applied mathematics (NAAm) Research Group Faculty of ScienceKing Abdulaziz University P.O.Box 80203 Jeddah 21589 Saudi Arabia Department of mathematics and Research Center for Complex Systems and Network Sciences Southeast University

Combined effects of Soret(thermal-diffusion) and Dufour(diffusion-thermo) in mHD stagnation point flow by a permeable stretching cylinder were studied. Analysis was examined in the presence of heat generation/absorption and chemical reaction. The laws of conservation of mass, momentum, energy and concentration are found to lead to the mathematical development of the problem. Suitable transformations were used to convert the nonlinear partial differential equations into the ordinary differential equations. The series solutions of boundary layer equations through momentum, energy and concentration equations were *** of the developed series solutions was discussed via plots and numerical values. The behaviors of different physical parameters on the velocity components, temperature and concentration were obtained. Numerical values of Nusselt number, skin friction and Sherwood number with different parameters were computed and analyzed. It is found that Dufour and Soret numbers result in the enhancement of temperature and concentration distributions, respectively.

关键词： stagnation point flow Soret-Dufour effects stretching cylinder suction/injection chemical reaction

Historical Arabic Images Classification and Retrieval Using Siamese Deep Learning model

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Computers, materials & Continua 2022年第7期72卷 2109-2125页

作者： manal m.Khayyat Lamiaa A.Elrefaei mashael m.Khayyat Computer Science Department Umm Al-Qura UniversityMakkahSaudi Arabia Computer Science Department King Abdulaziz UniversityJeddahSaudi Arabia Electrical Engineering Department Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of Information Systems and Technology College of Computer Science and EngineeringUniversity of JeddahJeddahSaudi Arabia

Classifying the visual features in images to retrieve a specific image is a significant problem within the computer vision field especially when dealing with historical faded colored ***,there were lots of efforts trying to automate the classification operation and retrieve similar images *** reach this goal,we developed a VGG19 deep convolutional neural network to extract the visual features from the images ***,the distances among the extracted features vectors are measured and a similarity score is generated using a Siamese deep neural *** Siamese model built and trained at first from scratch but,it didn’t generated high evaluation ***,we re-built it from VGG19 pre-trained deep learning model to generate higher evaluation ***,three different distance metrics combined with the Sigmoid activation function are experimented looking for the most accurate method formeasuring the similarities among the retrieved *** that the highest evaluation parameters generated using the Cosine distance ***,the Graphics Processing Unit(GPU)utilized to run the code instead of running it on the Central Processing Unit(CPU).This step optimized the execution further since it expedited both the training and the retrieval time *** extensive experimentation,we reached satisfactory solution recording 0.98 and 0.99 F-score for the classification and for the retrieval,respectively.

关键词： Visual features vectors deep learning models distance methods similar image retrieval