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A Beamforming Technique Using rotman Lens Antenna for Wireless relay Networks

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Computers, Materials & Continua 2022年第12期73卷 5641-5653页

作者： samer Alabed Mohammad Al-rabayah Wael Hosny Fouad aly College of Engineering and Technology American University of the Middle EastKuwait

rotman lens,which is a radio frequency beam-former that consists of multiple input and multiple output beam ports,can be used in industrial,scientific,and medical applications as a beam steering *** input ports collect the signals to be propagated through the lens cavity toward the output ports before being transmitted by the antenna arrays to the destination in order to enhance the error performance by optimizing the overall signal to noise ratio(sNr).In this article,a low-cost rotman lens antenna is designed and deployed to enhance the overall performance of the conventional cooperative communication systems without needing any additional power,extra time or frequency *** the suggested system,the smart rotman lens antennas generate a beam steering in the direction of the destination to maximize the received sNr at the destination by applying the proposed optimal beamforming *** suggested optimal beamforming technique enjoys high diversity,as well as,low encoding and decoding ***,we proved the advantages of our suggested strategy through both theoretical results and simulations using Monte Carlo *** Monte Carlo simulations show that the suggested strategy enjoys better error performance compared to the current state-of-the-art distributed multiantenna *** addition,the bit error rate(BEr)curves drawn from the analytical results are closely matching to those drawn from our conducted Monte Carlo simulations.

关键词： Performance analysis smart antenna rotman lens antenna multiantenna systems wireless relay networks cooperative diversity schemes digital network coding relay selection schemes

Multimodality image registration and fusion using neural network

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Journal of Harbin Institute of Technology(New series) 2003年第3期10卷 235-240页

作者： Mostafa G Mostafa aly A Farag Edward Essock Computer Vision and Image Processing Laboratory Dept. of Electrical and Computer Engineering University of Louisville Louisville KY 40292 USAComputer Vision and Image Processing Laboratory Dept. of Electrical and Computer Engineering University of Louisville Louisville KY 40292 USADept. of Psychology University of Louisville Louisville kY 40292 USA

Multimodality image registration and fusion are essential steps in building 3-D models from remotesensing data. We present in this paper a neural network technique for the registration and fusion of multimodali-ty remote sensing data for the reconstruction of 3-D models of terrain regions. A FeedForward neural network isused to fuse the intensity data sets with the spatial data set after learning its geometry. results on real data arepresented. Human performance evaluation is assessed on several perceptual tests in order to evaluate the fusionresults.

关键词： data fusion image registration image interpolation neural network, 3-D model building

The effect of nanosized CoFe2O4 addition on the magnetic properties of GdBa2Cu3O7-δ using AC magnetic susceptibility measurements

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Journal of Advanced Ceramics 2016年第1期5卷 93-101页

作者： r.AWAD N.H.MOHAMMED A.I.ABOU aly s.IsBEr H.A.MOTAWEH D.EL-sAID BAKEEr M.rOUMI(E) Physics Department Faculty of Science Alexandria University Alexandria EgyptPhysics Department Faculty of Science Beirut Arab University Lebanon Physics Department Faculty of Science Alexandria University Alexandria Egypt Physics Department American University of Beirut Beirut Lebanon Physics Department Faculty of Science Damanhur University Damanhur Egypt Accelerator Laboratory Lebanese Atomic Energy Commission Beirut Lebanon

superconductor samples of type (CoFe2O4)xGdBa2Cu3O7-δ (0≤x≤0.1) were synthesized by the conventional solid-state reaction technique, whereas nanosized CoFe2O4 was prepared by co-precipitation method with grain size of about 8.5 nm. The elemental content of the prepared samples was determined using particle induced X-ray emission (PIXE). The temperature dependence of real (χ') and imaginary (χʺ) components of AC magnetic susceptibility (ACMs) at different magnetic field amplitude (3–15 Oe) was investigated. The analysis of the temperature dependence of ACMs was performed using Bean critical state model. The values of the critical current density J c at T > T p (T p is the inter-granular loss peak temperature) were calculated as a function of magnetic field and nanosized CoFe2O4 content. It was found that the low nanosized CoFe2O4 addition content (x = 0.01) improves the critical current density J c of Gd-123 superconducting phase. The observed variation of J c with temperature indicated that the weak links are changed from superconductor–normal metal–superconductor (sNs) for free sample to superconductor–insulator–superconductor (sIs) type of junctions for samples added with nanosized CoFe2O4 of x > 0.01. We also discussed the experimental results in the framework of the critical state model to estimate the effective volume fraction of the grains f g using Cole–Cole plots.

关键词： Gd-123 phase nanosized CoFe2O4 AC magnetic susceptibility (ACMs) critical current density particle induced X-ray emission (PIXE)

simulation of Water-soil-structure Interactions Using Incompressible smoothed Particle Hydrodynamics

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Computers, Materials & Continua 2020年第10期65卷 205-224页

作者： Abdelraheem M.aly Mitsuteru Asai Ehab Mahmoud Mohamed Department of Mathematics College of ScienceKing Khalid UniversityAbha62529Saudi Arabia Department of Mathematics Faculty of ScienceSouth Valley UniversityQena83523Egypt Civil Engineering Department Kyushu UniversityFukuoka819-0395Japan Electrical Engineering Department College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addwasir11991Saudi Arabia Electrical Engineering Department Faculty of EngineeringAswan UniversityAswan81542Egypt

In the present work,an incompressible smoothed particle hydrodynamic(sPH)method is introduced to simulate water-soil-structure *** the current calculation,the water is modelled as a Newtonian *** soil is modelled in two different *** the first case,the granular material is considered as a fluid where a Bingham type constitutive model is proposed based on Mohr-Coulomb yield-stress criterion,and the viscosity is derived from the cohesion and friction *** addition,the fictitious suspension layers between water and soil depending on the concentration of soil are *** the second case,Hooke’s law introduces elastic *** IsPH,the pressure is evaluated by solving the pressure Poisson equation using a semi-implicit algorithm based on the projection method and an eddy viscosity for water is modelled by a large eddy simulation with the smagorinsky *** the proposed IsPH method,the pressure is stabilized to simulate the multiphase flow between soil and *** experiments for water-soil suspension flow of Louvain erosional dam break with flat soil foundation,is simulated and validated using 3D-IsPH *** between water-soil interactions with different solid structures are *** results revealed that,the suspension layers with the Bingham model of soil gives more accurate results in the experiment as compared to the case of the Bingham model without suspension *** addition,the elastic soil model by the Hooke’s law can simulate soil hump accurately as compared to the Bingham *** the simulations,avoiding erosion behind the structure for preventing the structure break during flood are investigated by using an extended structure or a wedge structure.

关键词： Bingham model IsPH method rigid body water-soil interactions

Prevalence of refractive Errors among school Children Aged 5 to 15 Years Old at CHU-IOTA

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surgical science 2024年第8期15卷 480-491页

作者： Kadiatou Ba Aichata Tall Mory Coulibaly Cheick sogodogo Zoumana Bagayogo Aoua Ibrahim Toure Ousmane Toure Brainima Coulibaly Fatoumata Tata sidibe aly Konipo roucky sangare seydou Diallo Moro sidibe Oumar Diallo Assiatou simaga Gounon saye Modibo sissoko Mamadou Kole sidibe sidi Diarra Nouhoum Guirou Abdoulaye Napo Adama Guindo University Hospital Center Institute of Tropical Ophthalmology of Africa (CHU-IOTA) Bamako Bamako Mali Ophthalmology Department Sikasso Regional Hospital Sikasso Mali Ophthalmology Department Luxembourg Mother-Child Hospital in Bamako Bamako Mali

Introduction: Undetected refractive errors constitute a health problem among school children who cannot take advantage of educational opportunities. The authors studied the prevalence of refractive errors in school children aged 5 to 15 at CHU-IOTA. Patients and Method: This is a prospective, descriptive cross-sectional study carried out in the ophthalmic-pediatrics department of CHU-IOTA, from October to November 2023. results: We received 340 school children aged 5 to 15, among whom 111 presented ametropia, i.e. a prevalence of 32.65%. The average age was 11.42 ± 2.75 years and a sex ratio of 0.59. The average visual acuity was 4/10 (range 1/10 and 10/10). We found refractive defects: astigmatism 73.87%, hyperopia 23.87% of cases and myopia 2.25%. The decline in distance visual acuity was the most common functional sign. Ocular abnormalities associated with ametropia were dominated by allergic conjunctivitis (26.13%) and papillary excavation (6.31%) in astigmatics;allergic conjunctivitis (9.01%) and papillary excavation (7.20%) in hyperopic patients;turbid vitreous (0.90%), myopic choroidosis (0.45%) and allergic conjunctivitis (0.45%) in myopes. Conclusion: refractive errors constitute a reality and a major public health problem among school children.

关键词： refractive Errors Prevalence Child CHU-IOTA

Prevalence of Ocular Trauma at the reference Health Center (CsrEF) of Kati

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surgical science 2024年第5期15卷 371-380页

作者： Kadiatou Ba Aichata Tall Brainima Coulibaly sadio Cissoko Bakary Danfaga Moro sidibe seydou Diallo Oumar Diallo Fatoumata Tata sidibe aly Konipo Mory Coulibaly Ousmane Touré Aoua I. Touré Cheick sogodogo Ibrahim Bamenta Gounon saye Modibo sissoko Mamadou Kole sidibe sidi Diarra Nouhoum Guirou Lamine Traoré University Hospital Center Institute of Tropical Ophthalmology of Africa Bamako Bamako Mali Ophthalmology Department Kati Reference Health Center Koulikoro Mali Ophthalmology Department Sikasso Regional Hospital Sikasso Mali Ophthalmology Department Luxembourg Mother-Child Hospital in Bamako Bamako Mali Ophthalmology Department Somin&#233 Dolo Mopti Regional Hospital in Mopti Mopti Mali National Eye Health Program Bamako Mali

Introduction: The authors wanted to study the prevalence of ocular trauma in the ophthalmology unit of the CsrEF of Kati. Patients and method: This is a retrospective study, covering the period from January to December 2015, carried out in the ophthalmology unit of the CsrEF in Kati. results: The sample consisted of 568 patients, or 6.82% of ophthalmological consultations. Children aged 0 to 14 years accounted for 154 (27.11%) of the trauma cases. Bruises constitute the main circumstance (58.1%) of eye trauma, followed by domestic accidents (15.6%). Closed globe ocular trauma was the main type of trauma (61.6%), followed by ocular adnexal trauma (30.1%) and open globe trauma (8.3%) in which the penetrating wound was the lesion, the least common (2.6%) but the most serious. Medical treatment was the most used therapeutic modality in 82.4% of cases, followed by surgery with 17.6% of cases. The evolution of the lesions after treatment was favorable in 85.6% of cases and unfavorable in 14.4% of cases. Complications were observed in 5.8% of cases and sequelae in 8.6% of cases. Conclusion: Ocular trauma constitutes an important reason for ophthalmological consultation at the CsrEF of Kati. The severity of some of these lesions requires frequent recourse to surgery. The complexity of the treatment should encourage us to favor preventive measures.

关键词： Eye Trauma Prevalence CsrEF Kati

Comparative studies on Y(Ⅲ)and Dy(Ⅲ)extraction from hydrochloric and nitric acids by Cyanex 572 as a novel extractant

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Journal of rare Earths 2018年第12期36卷 1342-1350页

作者： N.E.El-Hefny M.s.Gasser sh.sh.Emam W.H.Mahmoud H.F.aly Hot Laboratories Centre Atomic Energy Authority Faculty of science Ain Shams University

Extraction of Y(III) and Dy(III) from hydrochloric and nitric acids by Cy-572 in kerosene was studied. The factors affecting the extraction were separately investigated. The stoichiometry of the extracted species was deduced on the basis of slope analysis method. Evaluation of extraction equilibrium and stripping investigation was studied as well as saponification effect of Cy-572. The composition of the extracted metal species in the organic phase was found to be [MA·(HA)] for Y(III) or Dy(III) in both media.1.0 mol/L HCI is the best stripping agent for each metal ion from the studied acidic media in one *** Cy-572 does not exhibit any selectivity towards the extraction of Y(III) or Dy(III) from both HCI and HNOsolutions. Based on the obtained results, the data were compared and the separation feasibility between lanthanides and Y(III) in the two media was discussed.

关键词： Extraction Cyanex-572 Yttrium Lanthanides separation factor saponification

PLANNED LEAD TIME OPTIMIZATION IN MATErIAL rEQUIrEMENT PLANNING ENVIrONMENT FOr MULTILEVEL PrODUCTION sYsTEMs

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Journal of systems science and systems Engineering 2008年第2期17卷 132-155页

作者： Faicel HNAIEN Alexandre DOLGUI Mohamed-aly OULD LOULY Industrial Engineering and Computer science Centre(G2I)Ecole des Mines de st Etienne 158cours Fauriel42023 Saint EtienneFrance King saud University College of Engineering-Industrial Engineering Department P.O.B 800 Riyadh 11421Kingdom of Saudi Arabia

This paper deals with the problem of planned lead time calculation in a Material requirement Planning （MrP） environment under stochastic lead times. The objective is to minimize the sum of holding and backlogging costs. The proposed approach is based on discrete time inventory control where the decision variables are integer. Two types of systems are considered： multi-level serial-production and assembly systems. For the serial production systems （one type of component at each level）, a mathematical model is suggested. Then, it is proven that this model is equivalent to the well known discrete Newsboy Model. This directly provides the optimal values for the planned lead times. For multilevel assembly systems, a dedicated model is proposed and some properties of the decision variables and objective function are proven. These properties are used to calculate lower and upper limits on the decision variables and lower and upper bounds on the objective function. The obtained limits and bounds open the possibility to develop an efficient optimization algorithm using, for example, a Branch and Bound approach. The paper presents the proposed models in detail with corresponding proofs and se＇~eral numerical examples. some advantages of the suggested models and perspectives of this research are discussed.

关键词： Multilevel assembly and production control model planned lead time optimization systems MrP random lead times discrete inventory

Mangrove derived fungal endophytes–a chemical and biological perception

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Fungal Diversity 2013年第4期61卷 1-27页

作者： Abdessamad Debbab Amal H.aly Peter Proksch Heinrich-Heine-Universität Düsseldorf Institut für Pharmazeutische Biologie und BiotechnologieUniversitätsstr.1Geb.26.2340225 DüsseldorfGermany

The potential of mangrove-derived endophytic fungi as a promising source of diverse and structurally unprecedented bioactive natural products is unquestionable and continues to attract considerable *** review highlights new bioactive mangrove fungal metabolites and known compounds with hitherto unreported biological activities described during the last 10 *** compounds are categorized according to their reported biological activities,including cytotoxic,anti-infective,in addition to a wide range of miscellaneous activities such as protein kinase,αglucosidase,acetylcholinesterase and tyrosinase inhibitory activities,as well as antiangiogenic and neovascularisation effects,radical scavenging,DNA-binding affinity,and calcium and potassium channel blocking activity.

关键词： Fungi Endophytes Mangroves Bioactive natural products