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Crop Discrim.nation Using Field Hyper Spectral Rem.tely Sensed Data

Advances in Rem.te Sensing 2013年第2期2卷 63-70页

作者： sayed m. arafat m.ham.d A. Aboelghar Eslam.F. Ahm.d Agriculture Applications Departm.nt National Authority for Remote Sensing and Space Sciences (NARSS)Cairo Egypt

Crop discrim.nation through satellite im.gery is still problem.tic. Accuracy of crop classification for high spatial resolution satellite im.gery in the intensively cultivated lands of the Egyptian Nile delta is still low. Therefore, the m.in objective of this research is to determ.ne the optim.l hyperspectral wavebands in the spectral range of (400 - 2500 nm. to discrim.nate between two winter crops (Wheat and Clover) and two sum.er crops (m.ize and Rice). This is considered as a first step to im.rove crop classification through satellite im.gery in the intensively cultivated areas in Egypt. Hyperspectral ground m.asurem.nts of ASD field Spec3 spectroradiom.ter was used to m.nitor the spectral reflectance profile during the period of the m.xim.m.growth stage of the four crops. 1-nm.wide was aggregated to 10-nm.wide bandwidths. After accounting for atm.spheric windows and/or areas of significant noise, a total of 2150 narrow bands in 400 - 2500 nm.were used in the analysis. Spectral reflectance was divided into six spectral zones: blue, green, red, near-infrared, shortwave infrared-I and shortwave infrared-II. One Way ANOVA and Tukey’s HSD post hoc analysis was perform.d to choose the optim.l spectral zone that could be used to differentiate the different crops. Then, linear regression discrim.nation (LDA) was used to identify the specific optim.l wavebands in the spectral zones in which each crop could be spectrally identified. The results of Tukey’s HSD showed that blue, NIR, SWIR-1 and SWIR-2 spectral zones are m.re sufficient in the discrim.nation between wheat and clover than green and red spectral zones. At the sam. tim., all spectral zones were quite sufficient to discrim.nate between rice and m.ize. The results of (LDA) showed that the wavelength zone (727:1299 nm. was the optim.l to identify clover crop while three zones (350:712, 1451:1562, 1951:2349 nm. could be used to identify wheat crop. The spectral zone (730:1299 nm. was the optim.l to identify m.ize

关键词： Hyper Spectral Data Crop Discrim.nation

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A Study of Linke Turbidity Factor over Qena / Egypt

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Advances in Atm.spheric Sciences 1996年第4期13卷 519-532页

作者： sayed m. Elshazly Departm.nt of Physics Faculty of Science South Valley University Qena/A.R. Egypt

Data on instantaneous atm.spheric Linke turbidity factor TL (m. are reported for clear days at Qena/Egypt in the period from.June 1992 to m.y ***(m. is determ.ned using the values of irradiance of direct solar radiation (I),which are calculated from.global (G) and diffuse (D) - solar radiation *** and seasonally variations of both diurnal and daily average values of TL (m. increases steadily in the direction of sunset in the m.nths from.June to Decem.er 1992 as well as Sum.er and Autum. seasons,while it falls generally in this direction for the m.nths from.January to m.rch and Winter *** April and m.y,TL (m. fluctuates obviously through the day hours,it is also shown that the average values of TL(m. are particularly large during Sum.er m.nths com.ared to other m.nths of the *** behavior of TL(m. is discussed in view of the variations of som. weather elem.nts,which affect the content of water vapor and dust particle in the atm.sphere of the study *** seem. t be of sim.lar trends to that of other locations inside and outside *** virtual variation of TL(m. is elim.nated by reducing its value to relative optical air m.ss m.2,according to Kasten *** resulting TL (2) is m.re representative for the content of dust particles and water vapor in the atm.sphere.

关键词： Turbidity Linke turbidity factor Seasonal and diurnal variations Solar radiations com.onents m.asurem.nts Aerosol

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m.deling particle sedim.ntation in viscous fluids with a coupled im.ersed boundary m.thod and discrete elem.nt m.thod

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Particuology 2017年第2期15卷 191-199页

作者： sayed m. Derakhshani Dingena L. Schott Gabriel Lodewijks Faculty of m.chanical Maritime and Materials Engineering Delft University of Technology Delft Netherlands Departm.nt of m.chanical Engineering Faculty of Engineering University of Isfahan Isfahan Iran

Num.rical techniques have increasingly been used to m.del fluid–particle two-phase flows. Coupling the im.ersed boundary m.thod （IBm. and discrete elem.nt m.thod （DEm. is one prom.sing approach for m.deling particulate flows. In this study, IBm.was coupled with DEm.to im.rove the reliability and accuracy of IBm.for determ.ning the positions of particles during the sedim.ntation process within viscous fluids. The required ratio of the particle diam.ter to the grid size （D/dx） was determ.ned by com.aring the sim.lation results with the analytical solution and experim.ntal data. A dynam.c m.sh refinem.nt m.del was utilised in the IBm.m.del to refine the com.utational fluid dynam.cs grid near the particles. In addition, an optim.m.coupling interval between the IBm.and DEm.m.dels was determ.ned based on the experim.ntal results of a single particle sedim.ntation within silicon oil at a Reynolds num.er of 1.5. The experim.ntal results and the analytical solution were then utilised to validate the IBm.DEm.m.del at Reynolds num.ers of 4.1, 11.6, and 31.9. Finally, the validated m.del was utilised to investigate the sedim.ntation process for m.re than one particle by m.deling the drafting-kissing-tum.ling process and the Boycott phenom.non. Benchm.rk tests showed that the IBm.DEm.technique preserves the advantages of DEm.for tracking a group of particles, while the IBm.provides a reliable and accurate approach for m.deling the particle–fluid interaction.

关键词： Im.ersed boundary m.thod Discrete elem.nt m.thod Particle sedim.ntation Boycott phenom.non

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m.taheuristic Optim.zation for m.bile Robot Navigation Based on Path Planning

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Com.uters, m.terials & Continua 2022年第11期73卷 2241-2255页

作者： El-sayed m.El-kenawy Zeeshan Shafi Khan Abdelham.ed Ibrahim.Bandar Abdullah Aloyaydi Hesham.arafat Ali Ali E.Takieldeen Departm.nt of Com.unications and Electronics Delta Higher Institute of Engineering and TechnologyMansoura35111Egypt Faculty of Artificial Intelligence Delta University for Science and TechnologyMansoura35712Egypt Com.uter Science Departm.nt College of Engineering and Computer ScienceMustaqbal UniversityBuraidahSaudi Arabia Com.uter Engineering and Control System. Departm.nt Faculty of EngineeringMansoura UniversityMansoura35516Egypt Departm.nt of m.chanical Engineering Qassim UniversityBuraidah51452Saudi Arabia

Recently,the path planning problem.m.y be considered one of the m.st interesting researched topics in autonom.us *** is why finding a safe path in a cluttered environm.nt for a m.bile robot is a significant requisite.A prom.sing route planning for m.bile robots on one side saves tim. and,on the other side,reduces the wear and tear on the robot,saving the capital *** route planning m.thods for the m.bile robot have been developed and *** to our best knowledge,no m.thod offers an optim.m.solution am.ng the existing *** Swarm.Optim.zation(PSO),a num.rical optim.zation m.thod based on the m.bility of virtual particles in a m.ltidim.nsional space,is considered one of the best algorithm. for route planning under constantly changing environm.ntal *** the researchers,reactive m.thods are increasingly com.on and extensively used for the training of neural networks in order to have efficient route planning for m.bile *** paper proposes a PSO Weighted Grey Wolf Optim.zation(PSOWGWO)*** is a hybrid algorithm.based on enhanced Grey Wolf Optim.zation(GWO)with *** order to m.asure the statistical efficiency of the proposed algorithm.Wilcoxon rank-sum.and ANOVA statistical tests are *** experim.ntal results dem.nstrate a 25%to 45%enhancem.nt in term. of Area Under Curve(AUC).m.reover,superior perform.nce in term. of data size,path planning tim.,and accuracy is dem.nstrated over other state-of-the-art techniques.

关键词： m.bile robot swarm.optim.zation robot route planning neural networks

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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 m.stafa 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

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Assessm.nt of clay stiffness and strength param.ters using index properties

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Journal of Rock m.chanics and Geotechnical Engineering 2018年第3期10卷 579-593页

作者： sayed m.Ahm.d Structural Engineering Departm.nt Ain Shams University

A new approach is developed to determ.ne the shear wave velocity in saturated soft to firm.clays using m.asurem.nts of the liquid lim.t, plastic lim.t, and natural water content with depth. The shear wave velocity is assessed using the site-specific variation of the natural water content with the effective m.an stress. Subsequently, an iterative process is envisaged to obtain the clay stiffness and strength *** at-rest earth pressure coefficient, as well as bearing capacity factor and rigidity index related to the cone penetration test, is also acquired from.the analyses. Com.arisons are presented between the m.asured clay param.ters and the results of corresponding analyses in five different case studies. It is dem.nstrated that the presented approach can provide acceptable estim.tes of saturated clay stiffness and strength param.ters. One of the m.in privileges of the presented m.thodology is the site-specific procedure developed based on the relationships between clay strength and stiffness param.ters, rather than adopting direct correlations. Despite of the utilized iterative processes, the presented approach can be easily im.lem.nted using a sim.le spreadsheet, benefiting both geotechnical researchers and practitioners.

关键词： Soft to firm.clays Atterberg lim.ts Shear wave velocity Sm.ll-strain shear m.dulus Constrained m.dulus Undrained shear strength Effective friction angle Cone penetration test

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Use of breakthrough experim.nt to evaluate the perform.nce of hydrogen isotope separation for m.tal-organic fram.works m.m.F-74(m.Co, Ni, m., Zn)

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Science China Chem.stry 2020年第7期63卷 881-889页

作者： Yanan Si Wenjing Wang El-sayed m.El-sayed Daqiang Yuan State Key Laboratoty of Structural Chem.stry Fujian Institute o f Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of the Chinese Academ. of Sciences Beijing 100049China Chem.cal Refining Laboratory Refining DepartmentEgyptian Petroleum Research InstituteNasr CityCairoEgypt

The unique adsorption perform.nce of m.tal-organic fram.works(m.Fs) indicates a new direction for gas separation and purification. The low-tem.erature distillation, as a traditional technique for hydrogen isotope separation, is lim.ted as it is a high energy-and cost-intensive process. Instead of utilizing such a conventional separation route, we use ordered m.croporous fram.works based on a physical adsorption m.chanism.to solve the challenge of hydrogen isotope separation. Herein we analyze m.m.F-74(m.Co, Ni, m., Zn), featuring a hexagonal channel about 11 ? and high density of open m.tal sites, for their ability to separate and purify deuterium.from.the hydrogen isotope m.xture by dynam.c colum. breakthrough experim.nts. Our results show that the com.ination of the strength of binding sites, density of coordinatively unsaturated m.tal sites and hydrogen isotope adsorption capacity of m.terials renders Co-m.F-74 as an optim.l adsorbent for the capture of deuterium.from.hydrogen isotope m.xtures in a sim.lated industrial process.

关键词： hydrogen isotope separation breakthrough experim.nt m.F-74

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Effects of Nickel Distribution on the Strengthening and Toughening of Alum.na Ceram.cs

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Journal of m.terials Science & Technology 2008年第5期24卷 723-728页

作者： m.ham.d.m.El-sayed Selem.n Departm.nt of m.terials and m.tallurgical Eng. Faculty of Petroleum and Mining Eng.Post Code 43721SuezEgypt

Three types of com.osite m.terials were designed and fabricated by hot pressing powder blends of alum.na with 20 vol. pct nickel particles. The com.osites differ in the shape, size and distribution of the nickel particles. Com.osite m.crostructures are described and m.asurem.nts of density, hardness, flexure strength, and fracture toughness are reported. The results showed that the fracture strength of the com.osite with dispersed nickel particles is higher than the other two com.osites （network m.crostructure and m.xed m.crostructure） and the alum.na m.trix. For all the com.osites studied, tougher m.terials than the m.nolithic alum.na were produced. The fracture toughness of the com.osite with a network m.crostructure is m.ch higher than that of the other com.osites. The toughening m.chanism. were described based on the observation of the fracture surfaces and the crack-particle interactions. m.reover, the param.ters for m.crostructural tailoring of these m.terials have been deduced. The toughening of the produced com.osites was explained in light of the interracial bond strength.

关键词： Alum.na-nickel com.osites Nickel m.rphology Interfacial bonding Fracturetoughness Flexure strength

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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. m.stafa 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.

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Vibrational, rotational, and triaxiality features in extended O(6) dynam.cal sym.etry of IBm.using three-body interactions

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Nuclear Science and Techniques 2020年第5期31卷 44-56页

作者： A.m.Khalaf Azza O.El-Shal m.m.Taha m.A.El-sayed Physics Departm.nt Faculty of ScienceAl-Azhar UniversityCairoEgypt m.them.tics and Theoretical Physics Departm.nt Nuclear Research CenterAtomic Energy AuthorityCairo 13759Egypt

The shape transition between the vibrational U(5)and deform.d c-unstable O(6)dynam.cal sym.etries of sd interacting boson m.del has been investigated by considering a m.dified O(6)Ham.ltonian,providing that the coefficients of the Casim.r operator of O(5)are N-dependent,where N is the total num.er of *** m.dified O(6)Ham.ltonian does not contain the num.er operator of the d boson,which is responsible for the vibrational *** addition,the deform.tion features can be achieved without using the SU(3)lim.t by adding to the O(6)dynam.cal sym.etry the three-body interaction[QQQ]^(0),where Q is the O(6)sym.etric quadrupole ***,triaxiality can be generated through the inclusion of the cubic d-boson interaction[d+d+d+]^(3)·∣ddd∣^(3).The classical lim.t of the potential energy surface(PES),which represents the expected value of the total Ham.ltonian in a coherent state,is studied and *** m.dified O(6)m.del is applied to the even–even^124-132 Xe *** param.ters for the Ham.ltonian and the PESs are calculated using a sim.lated search program.to obtain the m.nim.m.root m.an square deviation between the calculated and experim.ntal excitation energies and B(E2)values for a num.er of low-lying levels.A good agreem.nt between the calculations and experim.nt results is found.

关键词： Nuclear structure Extended O(6)of IBm Three-body interactions Coherent state

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