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Journal of Food Science and Engineering 2012年第10期2卷 564-575页

作者： Aym.n H. Am.r Eissa Abdul Rahm.n O. Alghannam.mostafa m. azam Departm.nt of Agriculture System. Engineering College of Agricultural and Food Sciences King Faisal University P.O. Box 420Al-Hassa 31982 Saudi Arabia Agriculture Engineering Departm.nt Faculty of Agriculture Minoufiya University Shibin El-Kom Egypt

In order to better design, fabricate and control pear handling m.chine, we should take into account m.chanical and rheological properties of pear fruits as related to handling process. The changes in rheological properties of pears stored at 5, 15, 25 ℃ and variable （fluctuating） tem.erature for 12 days were evaluated in term. of elasticity and viscosity param.ters using creep tests. The elasticity and viscosity param.ters in creep tests in general decreased with increase in storage tim. both under constant and variable storage conditions. For the variable storage condition, a bulk m.an tem.erature calculated to account for a series com.ination of storage tim. and tem.erature to which the pears subjected. The changes in rheological properties due to variable storage tem.erature were described as a function of storage tim.. The result indicated that except the viscosity param.ter of the m.xwell com.onent of the four-elem.nt m.del, it was possible to describe the changes in rheological properties as a function of storage tim., which are better physical param.ters to estim.te the quality of pears.

关键词： m.deling rheological and m.chanical properties pears storage Burger's m.del creep test.

Im.uting m.ssing values using cum.lative linear regression

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CAAI Transactions on Intelligence Technology 2019年第3期4卷 182-200页

作者： Sam.h m. mostafa Faculty of Science Mathematics DepartmentComputer ScienceSouth Valley UniversityQena 83523Egypt

The concept of m.ssing data is im.ortant to apply statistical m.thods on the dataset. Statisticians and researchers m.y end up to an inaccurate illation about the data if the m.ssing data are not handled properly. Of late, Python and R provide diverse packages for handling m.ssing data. In this study, an im.utation algorithm. cum.lative linear regression, is proposed. The proposed algorithm.depends on the linear regression technique. It differs from.the existing m.thods, in that it cum.lates the im.uted variables;those variables will be incorporated in the linear regression equation to filling in the m.ssing values in the next incom.lete variable. The author perform.d a com.arative study of the proposed m.thod and those packages. The perform.nce was m.asured in term. of im.utation tim., root-m.an-square error, m.an absolute error, and coefficient of determ.nation (R^2). On analysing on five datasets with different m.ssing values generated from.different m.chanism., it was observed that the perform.nces vary depending on the size, m.ssing percentage, and the m.ssingness m.chanism. The results showed that the perform.nce of the proposed m.thod is slightly better.

关键词： Im.uting m.ssing values cum.lative linear regression statistical m.thods

Coupled hydroelastic vibrations of an elliptical cylindrical tank with an elastic bottom

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Journal of Hydrodynam.cs 2014年第2期26卷 264-276页

作者： HASHEm.NEJAD Seyyed m. TAFANI mostafa Acoustics Research Laboratory Center of Excellence in Experimental Solid Mechanics and Dynamics School of Mechanical Engineering Iran University of Science and Technology

An exact three-dim.nsional analysis based on the linear potential theory and the elaborated m.thod of eigenfunction expansion in elliptic coordinates are presented to study the free coupled elasto-hyrodynam.c characteristics of an upright non-deform.ble cylindrical container of elliptical planform.with a flexible bottom.plate, filled to an arbitrary depth with an inviscid incom.ressible liquid. Extensive num.rical data are presented in an orderly fashion for the first few sym.etric/anti-sym.etric coupled hydroelastic natural frequencies as a function of fluid depth param.ter for two plate aspect ratios. Also, selected hydrodynam.c and structural deform.tion m.des shapes are presented in graphical form. The effects of liquid level, bottom.plate elasticity, and cross sectional aspect ratio on the sloshing frequencies and hydrodynam.c pressure m.des are exam.ned. The validity of the results is exam.ned through com.utations using a com.ercial finite elem.nt package as well as by com.arison with the data available in literature.

关键词： exact solution fluid-structure interaction free surface oscillations vertical elliptical vessel m.thieu functions

Kinem.tic Analysis and Design of a 3-DOF Translational Parallel Robot

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International Journal of Autom.tion and com.uting 2017年第4期14卷 432-441页

作者： m.hm.od m.zare mostafa Taghizadeh m. Rasool Najafi School of m.chanical Engineering Shahid Beheshti University Tehran lran Departm.nt of Engineering University of Qom Qom Iran

Parallel m.chanism. are widely used in various fields of engineering and industrial applications such as m.chine tools, flight sim.lators, earthquake sim.lators, m.dical equipm.nt, etc. Parallel m.chanism. are restricted to som. lim.tations such as irregular workspace, existence of singular points and com.lexity of control system. which should be studied and analyzed for effective and efficient use. In this research, a new m.chine tool with parallel m.chanism.which has three translational degrees of freedom.is studied and the workspace and singular points are determ.ned by deriving analytical equations and then utilizing of m.tlab software. To do so, forward and inverse kinem.tics of the m.chanism.are obtained and workspace and singular points are calculated using a search algorithm. Afterward in order to validate the results, the proposed m.chanism.is sim.lated in autom.tic dynam.cs analysis of m.chanical system. （ADAm.） software. m.reover, in order to investigate the quality of robot perform.nce and dexterity of the m.chanism.in its workspace, global dexterity index （GDI） of the robot is calculated using Jacobean m.trix at different positions of the m.bile platform.

关键词： Kinem.tic analysis parallel robot workspace m.nipulability dexterity.

Accretion onto the m.gnetically Charged Regular Black Hole

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Chinese Physics Letters 2017年第7期34卷 38-40页

作者： m.azam A.Aslam Division of Science and Technology University of Education Lahore 54590 Pakistan

We investigate the accretion process for static spherically sym.etric geom.try, i.e., m.gnetically charged regular black hole with isotropic fluid. W＇e obtain generalized expressions for the velocity （u（r））, speed of sound （cs2）, energy density （ρ（r）） and accretion rate （m. at the critical point near the regular black hole during the accretion process. We also plot these physical param.ters against fixed values of charge, m.ss and different values of equation of state param.ter to study the process of accretion. We find that radial velocity and energy density of the fluid rem.in positive and negative as well as rate of change of m.ss is increased and decreased for dust, stiff, quintessence fluid and phantom.like fluid, respectively.

关键词： Accretion onto the m.gnetically Charged Regular Black Hole

Experim.ntal and m.them.tical m.deling of Cr(Ⅵ) rem.val using nano-m.gnetic Fe3O4-coated perlite from.the liquid phase

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Chinese Journal of Chem.cal Engineering 2020年第6期28卷 1582-1590页

作者： Ism.il m.Ahm.d mostafa m.Ham.d Sayed S.m.twally Chem.stry Departm.nt College of ScienceJouf UniversitySkakaSaudi Arabia Hot Laboratories and Waste m.nagem.nt Center Atomic Energy Authority13759 CairoEgypt

m.dification of perlite using nano-m.gnetic iron oxide was im.lem.nted to produce nano-m.gneticFe3O4-coated perlite com.osite(Fe3O4/Perlite).The prepared com.osite was characterized using Scanning Electron m.croscopy,Fourier-Transform.Infrared spectroscopy and Powder X-ray *** potentiality of both perlite and Fe3O4/Perlite com.osite to elim.nate Cr(VI)from.the environm.ntally relevant water was *** influence of m.in factors which could affect the adsorption was studied including;pH of m.dium.shaking tim. and Cr(VI)ions *** experim.ntal outcom. dem.nstrated that the m.dification of perlite by nano-m.gnetic Fe3O4 showed a significantly enhanced Cr(VI)rem.val efficiency relative to that of unm.dified *** the kinetic studies,the experim.ntal data fitted well with the pseudo-second-order ***,it proposes that Langm.ir isotherm.is m.re adequate than the Freundlich isotherm.for both perlite and m.dified *** results recom.ended that Fe3O4/Perlite com.osite had a great potential as an econom.c and efficient adsorbent of Cr(VI)from.contam.nated water,which has huge application potential.

关键词： Nano-m.gnetic Com.osite Kinetics Isotherm Perlite Adsorption

A m.lti-Factor Authentication-Based Fram.work for Identity m.nagem.nt in Cloud Applications

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Com.uters, m.terials & Continua 2022年第5期71卷 3193-3209页

作者： Wael Said Elsayed mostafa m.m.Hassan Aym.n m.ham.d mostafa Faculty of Com.uters and Inform.tics Zagazig UniversityZagazig44519Egypt College of Com.uter and Inform.tion Sciences Jouf UniversitySakaka72314Saudi Arabia

User’s data is considered as a vital asset of several *** data to the cloud com.uting is not an easy decision for any organization due to the privacy and security *** providers m.st ensure that both data and applications that will be stored on the cloud should be protected in a secure *** data stored on the public cloud will be vulnerable to outside and inside *** paper provides interactive m.lti-layer authentication fram.works for securing user identities on the *** access control policies are applied for verifying users on the cloud.A security m.chanism.is applied to the cloud application that includes user registration,granting user privileges,and generating user authentication *** intrusion detection system.is em.edded to the security m.chanism.to detect m.licious *** m.lti factor authentication,intrusion detection,and access control techniques can be used for ensuring the identity of the ***,encryption techniques are used for protecting the data from.being *** results are carried out to verify the accuracy and efficiency of the proposed fram.works and *** results recorded high detection rate with low false positive alarm..

关键词： Cloud com.uting service providers m.lti-layer authentication fram.works and access control

An Integrated Fram.work for Cloud Service Selection Based on BOm.and TOPSIS

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Com.uters, m.terials & Continua 2022年第8期72卷 4125-4142页

作者： Ahm.d m.mostafa Com.uter and System. Engineering Departm.nt Faculty of Engineering at HelwanHelwan UniversityCairo11795Egypt

m.ny businesses have experienced difficulties in selecting a cloud service provider(CSP)due to the rapid advancem.nt of cloud com.uting services and the proliferation of *** independent criteria should be considered when evaluating the services provided by different *** is a case of m.lti-criteria decision-m.king(m.Dm..This paper presents an integrated m.Dm.cloud service selection fram.work for determ.ning the m.st appropriate service provider based on the best only m.thod(BOm.and technique for order of preference by sim.larity to ideal solution(TOPSIS).To obtain the weights of criteria and the relative im.ortance of CSPs based on each criterion,BOm.perform. pairwise com.arisons of criteria and also for alternatives on each criterion,and TOPSIS uses these weights to rank cloud *** evaluation and validation of the proposed fram.work have been carried out through a use-case m.del to prove its efficiency and ***,the developed fram.work was com.ared with the analytical hierarchical process(AHP),a popular m.Dm.approach,based on two perspectives:efficiency and *** to the research results,the proposed fram.work only requires 25%of the com.arisons needed for the AHP ***,the proposed fram.work has a CR of 0%,whereas AHP has 38%.Thus,the proposed fram.work perform. better than AHPwhen it com.s to com.utation com.lexity and consistency,im.lying that it is m.re efficient and trustworthy.

关键词： Cloud com.uting(CC) m.ltiple-criteria decision-m.king(m.Dm. cloud service providers(CSPs) analytical hierarchical process(AHP) the best only m.thod(BOm. technique for order of preference by sim.larity to ideal solution(TOPSIS)

FIRST-ORDER m.THODS FOR SOLVING THE OPTIm.L STATIC H∞-SYNTHESIS PROBLEm

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Journal of Com.utational m.them.tics 2007年第6期25卷 672-689页

作者： El-Sayed m.E. mostafa Departm.nt of m.them.tics Faculty of Science Alexandria University Alexandria Egypt

In this paper, we consider the static output feedback （SOF） H∞-synthesis problem.posed as a nonlinear sem.-definite program.ing （NSDP） problem. Two num.rical algorithm. are developed to tackle the NSDP problem.by solving the corresponding Karush- Kuhn-Tucker first-order necessary optim.lity conditions iteratively. Num.rical results for various benchm.rk problem. illustrating the perform.nce of the proposed m.thods are given.

关键词： Static output feedback H∞-synthesis Sem.-definite program.ing Nonlinear program.ing.

The Stability of Som. Viable Stars and Electrom.gnetic Field

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Chinese Physics Letters 2016年第7期33卷 25-27页

作者： m.azam S.A.m.rdan m.A.Rehm.n Division of Science and Technology University of EducationTownship Campus Departm.nt of m.them.tics University of the Management and Technology

We exam.ne the im.act of electrom.gnetic field on the stability of com.act stars corresponding to em.edded class one m.tric using the concept of cracking. For this purpose, we develop the generalized hydrostatic equi- librium.equation for charged perfect fluid distribution of com.act stars and perturb it by m.ans of local density perturbation schem. to check the stability of inner m.tter configuration. We investigate the cracking of Her X-I, PSR 1937＋21, PSR J 1614-2230, PSR J 0348＋0432 and B.X J 1856-37. We conclude that PSR J 0348＋0432 and RX J 1856-37 exhibit cracking when charge is introduced on these astrophysical objects.

关键词： of in et it on PSR The Stability of Som. Viable Stars and Electrom.gnetic Field for