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Silicon micromirrors with three-dimensional curvature enabling lensless efficient coupling of free-space light

Light(Science & Applications) 2013年第1期2卷 98-106页

作者： yasser m sabry Bassam Saadany Diaa Khalil Tarik Bourouina Universite Paris-Est ESYCOM(EA 2552)ESIEE ParisF-93162 Noisy-le-GrandFrance Si-Ware Systems 3 Khaled Ibn El-Waleed StreetHeliopolisCairo 11361Egypt Electron.and Comm.Eng.Dept. Faculty of Eng.Ain-Shams UniversityCairoEgypt

miniaturized optical benches process free-space light propagating in-plane with respect to the substrate and have a large variety of applications,including the coupling of light through an optical *** coupling efficiency is usually obtained using assembled micro-optical parts,which considerably increase the system cost and integration *** this work,we report a high coupling efficiency,monolithically integrated silicon micromirror with controlled three-dimensional(3D)curvature that is capable of manipulating optical beams propagating in the plane of the silicon *** on our theoretical modeling,a spherical micromirror with a microscale radius of curvature as small as twice the Gaussian beam Rayleigh range provides a 100%coupling efficiency over a relatively long optical path *** dimensionless parameters facilitates the elucidation of the role of key design parameters,including the mirror’s radii of curvature,independent of the wavelength.A micromachining method is presented for fabricating the 3D micromirror using fluorinated gas *** measured coupling efficiency was greater than 50%over a 200-mm optical path,compared to less than 10%afforded by a conventional flat micromirror,which was in good agreement with the *** the 3D micromirror,an optical cavity was formed with a round-trip diffraction loss of less than 0.4%,resulting in one order of magnitude enhancement in the measured quality factor.A nearly 100%coupling was also estimated when matching the sagittal and tangential radii of curvature of the presented micromirror’s *** reported class of 3D micromirrors may be an advantageous replacement for the optical lenses usually assembled in silicon photonics and optical benches by transforming them into real 3D monolithic systems while achieving wideband high coupling efficiency over submillimeter distances.

关键词： coupling efficiency Gaussian beam coupling micro-optics monolithic chip optical cavity optical fabrication optical benches silicon photonics

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On-chip parallel Fourier transform spectrometer for broadband selective infrared spectral sensing

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microsystems & Nanoengineering 2020年第1期6卷 1267-1275页

作者： Alaa Fathy yasser m.sabry Sebastien Nazeer Tarik Bourouina Diaa A.Khalil Faculty of Engineering Ain-Shams University1 Elsarayat St.AbbassiaCairoEgypt Si-Ware Systems 3 Khalid Ibn Al-Waleed St.HeliopolisCairoEgypt UniversitéParis-Est ESYCOM EA 2552ESIEE Paris93162 Noisy-le-GrandFrance

Optical spectrometers enable contactless chemical ***,decreasing both their size and cost appears to be a prerequisite to their widespread ***-scale implementation of optical spectrometers still requires tackling two main ***,operation over a broad spectral range extending to the infrared is required to enable covering the molecular absorption spectrum of a broad variety of *** is addressed in our work with an micro-Electro mechanical Systems(mEmS)-based Fourier transform infrared spectrometer with an embedded movable micro-mirror on a silicon ***,fine spectral resolutionΔλis also required to facilitate screening over several chemicals.A fundamental limit states thatΔλis inversely proportional to the mirror motion range,which cannot exceed the chip *** boost the spectral resolution beyond this limit,we propose the concept of parallel(or multi-core)FTIR,where multiple interferometers provide complementary optical paths using the same actuator and within the same *** concept scalability is validated with 4 interferometers,leading to approximately 3 times better spectral *** the atmospheric contents of a greenhouse gas are monitored,the methane absorption bands are successfully measured and discriminated using the presented device.

关键词： interferometer spectral mirror

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A Proposed Feature Selection Particle Swarm Optimization Adaptation for Intelligent Logistics--A Supply Chain Backlog Elimination Framework

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Computers, materials & Continua 2024年第6期79卷 4081-4105页

作者： yasser Hachaichi Ayman E.Khedr Amira m.Idrees College of Computing and Information Technology at Khulais Department of Information SystemsUniversity of JeddahJeddah21959Saudi Arabia Faculty of Computers and Information Technology Future University in EgyptCairo11835Egypt

The diversity of data sources resulted in seeking effective manipulation and *** challenge that arises from the increasing dimensionality has a negative effect on the computation performance,efficiency,and stability of *** of the most successful optimization algorithms is Particle Swarm Optimization(PSO)which has proved its effectiveness in exploring the highest influencing features in the search space based on its fast convergence and the ability to utilize a small set of parameters in the search *** research proposes an effective enhancement of PSO that tackles the challenge of randomness search which directly enhances PSO *** the other hand,this research proposes a generic intelligent framework for early prediction of orders delay and eliminate orders backlogs which could be considered as an efficient potential solution for raising the supply chain *** proposed adapted algorithm has been applied to a supply chain dataset which minimized the features set from twenty-one features to ten significant *** confirm the proposed algorithm results,the updated data has been examined by eight of the well-known classification algorithms which reached a minimum accuracy percentage equal to 94.3%for random forest and a maximum of 99.0 for Naïve ***,the proposed algorithm adaptation has been compared with other proposed adaptations of PSO from the literature over different *** proposed PSO adaptation reached a higher accuracy compared with the literature ranging from 97.8 to 99.36 which also proved the advancement of the current research.

关键词： Optimization particle swarm optimization algorithm feature selection logistics supply chain management backlogs

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Heat Transfer Enhancement of the Absorber Tube in a Parabolic Trough Solar Collector through the Insertion of Novel Cylindrical Turbulators

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Fluid Dynamics & materials Processing 2024年第6期20卷 1279-1297页

作者： yasser Jebbar Fadhil Fluiful Wisam Khudhayer Department of Electrical Techniques Al-Mussaib Technical InstituteAl-Furat Al-Awsat Technical UniversityBabilIraq Department of Physics Collage of ScienceUniversity of KerbalaKarbalaIraq Department of Energy Engineering Collage of Engineering/Al-MusayabUniversity of BabylonBabilIraq

This study includes an experimental and numerical analysis of the performances of a parabolic trough collector(PTC)with and without cylindrical *** PTC is designed with dimensions of 2.00 m in length and 1.00 m in *** related reflector is made of lined sheets of aluminum,and the tubes are made of stainless steel used for the absorption of *** have an outer diameter of 0.051 m and a wall thickness of 0.002 ***,used as a heat transfer fluid(HTF),flows through the absorber tube at a mass flow rate of 0.7 kg/*** dimensions of cylindrical turbulators are 0.04 m in length and 0.047 m in *** are performed using the ANSYS Fluent 2020 R2 *** PTC performance is evaluated by comparing the experimental and numerical outcomes,namely,the outlet temperature,useful heat,and thermal efficiency for a modified tube(mT)(tube with novel cylindrical turbulators)and a plain tube(PT)(tube without novel cylindrical turbulators).According to the results,the experimental outlet temperatures recorded 63.2°C and 50.5°C for the mT and PT,*** heat gain reaches 1137.5 Win the mT and 685.8 Win the *** to the PT collector,the PTC exhibited a(1.64 times)higher efficiency.

关键词： Parabolic trough collector turbulators absorber tube ANSYS thermal efficiency

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Unraveling the nature of sensing in electrostatic mEmS gas sensors

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microsystems & Nanoengineering 2024年第3期10卷 109-117页

作者： yasser S.Shama Sasan Rahmanian Hamza mouharrar Rana Abdelrahman Alaaeldin Elhady Eihab m.Abdel-Rahman Systems Design Engineering University of Waterloo200 University Ave WWaterloo N2L 3G1 ONCanada mechanical Engineering Benha Faculty of EngineeringBenha UniversityBenha 13511Egypt

This paper investigates the fundamental sensing mechanism of electrostatic mEmS gas *** compares among the responsivities of a set of mEmS isopropanol sensors before and after functionalization,and in the presence and absence of electrostatic fields when operated in static and dynamic detection *** the static mode,we found that the sensors do not exhibit a measurable change in displacement due to added *** the other hand,bare sensors showed a clear change in displacement in response to isopropanol *** the dynamic mode,functionalized sensors showed a measurable frequency shift due to the added mass of isopropanol *** the presence of strong electrostatic fields,the measured frequency shift was found to be threefold larger than that in their absence in response to the same concentration of isopropanol *** enhanced responsivity of dynamic detection allows the sensors to measure the vapor mass captured by the functional material,which is not the case for static *** detection of isopropanol by bare sensors in static mode shows that change in the medium permittivity is the primary sensing *** enhanced responsivity of dynamic mode sensors when operated in strong electrostatic fields shows that their sensing mechanism is a combination of a weaker added mass effect and a stronger permittivity *** findings show that electrostatic mEmS gas sensors are independent of the direction of the gravitational field and are,thus,robust to changes in *** is erroneous to refer to them as‘gravimetric’sensors.

关键词： mechanism electrostatic measurable

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Light demand characteristics,production performance,and changes in the feeding patterns of broilers

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 68-73页

作者： Shouyi Wang Guoping Jiang Chenghao Pan Thebano Santos yasser Elhadidi Ahmed Jado Shufang Jin Jinming Pan College of Biosystems Engineering and Food Science Zhejiang UniversityHangzhou 310058China Infinova(Hangzhou)Information System Technology Co. Ltd.Hangzhou 310012China Center of Information Technology"Renato Archer"(CIT) Ministry of ScienceTechnologyInnovation and CommunicationCEP:13069-901 Campinas(SP)Brazil Department of Agricultural Engineering Mansoura UniversityMansoura 35516Egypt

Poultry is a light-sensitive animal and the light environment has an important influence on the growth and development of these *** studies have mainly focused on the effects of the light environment on various physiological indicators of poultry but seldom explored the light demand characteristics of broilers under free *** experiment mainly studied the light demand characteristics of broilers under a yellow LED light environment and the influence of different breeding densities[low-density(2.5 broilers/m^(2)),high-density(7.5 broilers/m^(2))]on the production performance and diet characteristics of *** showed that the production performance indexes of low-density groups are higher than those of high-density *** feed and water consumption in the light area of the two experimental groups were significantly higher than those in the dark area,which means that the broilers showed a great preference for the light ***,as the age of the broilers increased,the food and water consumption of the broilers decreased,indicating that broilers had a lower preference for light in the middle and late stages of *** statistical results for the residence frequency distribution characteristics showed that broiler chickens had different light requirements at different growth stages under the condition of active selection:1)low-density breeding environment:23.8L(light):0.2D(dark)for chicks and 22.3L:1.7D for adult broilers;2)high-density breeding environment:22.6L:1.4D for chicks and 15.0L:9.0D for adult *** study will provide a reference for the optimization and control of light environment in broiler breeding.

关键词： broiler light-demand characteristics production performance feeding pattern

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Interstitial cells of Cajal, the maestro in health and disease

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World Journal of Gastroenterology 2010年第26期16卷 3239-3248页

作者： Randa m mostafa yasser m moustafa Hosam Hamdy Department of Basic medical Sciences College of Medicine Sharjah University Sharjah 27272 United Arab Emirates Department of Pharmacology and Toxicology College of Pharmacy Suez Canal University Ismaelia 24421 Egypt Department of Surgery Vice Chancellor of Medical and Health sciences Colleges Sharjah University Sharjah 27272 United Arab Emirates

Interstitial cells of Cajal (ICC) are important players in the symphony of gut motility. They have a very signif icant physiological role orchestrating the normal peristaltic activity of the digestive system. They are the pacemaker cells in gastrointestinal (GI) muscles. Absence, reduction in number or altered integrity of the ICC network may have a dramatic effect on GI system motility. more understanding of ICC physiology will foster advances in physiology of gut motility which will help in a future breakthrough in the pharmacological interventions to restore normal motor function of GI tract. This mini review describes what is known about the physiologic function and role of ICCs in GI system motility and in a variety of GI system motility disorders.

关键词： Interstitial cells of Cajal Gastrointestinal motility Peristalsis

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ZnO DOPED SODIUm SILICATE PREIONIZE N_(2) LASER

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Chinese Physics Letters 1989年第11期6卷 491-494页

作者： m.montaser F.sabry S.A.Ibrahim hysics Department Faculty of ScienceMonofia UniversityShibin El-koamEgypt Faculty of Science Jordan Univ.of Science and Technology IrbidJordan

An experimental study of the effect of ZnO doped sodium silicate thin film,used as a semiconductive preionizer on the output energy is *** output energy of the nitrogen laser increased by two *** performance of the pr... 详细信息

关键词： LASER film conductive

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Preparation of solar-enhanced AlZnO@carbon nano-substrates for remediation of textile wastewaters

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Journal of Environmental Sciences 2020年第6期32卷 52-68页

作者： Esraa m.El-Fawal Sherif A.Younis yasser m.moustafa Philippe Serp Central Laboratories Analysis and Evaluation DepartmentEgyptian Petroleum Research InstituteNasr CityCairo 11727Egypt Laboratoire de Chimie de Coordination(LCC) Unite Propre de Recherche(UPR)Du Centre National de La Recherche Scientifique(CNRS)8241Composante de L’Ecole Nationale D’Ingenieurs en Arts Chimiques et Technologiques(ENSIACET)Universite de ToulouseUniversite Paul Sabatier(UPS)Institut National Polytechnique(INP)-LCC4 Allee Emile Monso31030Toulouse Cedex 4France

Photoactive aluminum doped ZnO(AlZnO)was synthesized by sol-gel *** that,AlZnO photocatalyst was deposited on five carbon-based materials(CBms)using ultrasonic route followed by solid-state mixing using ball *** CBms used were poly aniline(PANI),carbon nitride(CN),carbon nanotubes(CNT),graphene(G),and carbon nanofibers(CNF).The crystal phases,elemental compositions,morphological,and optical properties of the AlZnO@CBms composites were *** results revealed that two of AlZnO@CBms composites exhibited superior bleaching efficiency(100%removal)and photocatalytic stability(three cycles)for 50μmol/L methylene Blue(mB)contaminated water after 60 min irradiation in visible light at pH 6.5,0.7%H2O2,and 5 g/L inorganic *** optimum conditions,AlZnO@CBms nanocomposites were employed for the treatment of mixed dyestuffs composed of mB,methyl Orange(mO),Astrazone Blue FRR(BB 69),and Rhodamine B(RhB)dyes under dark,ultraviolet,visible,and direct *** mixed dyestuffs,the AlZnO@G achieved the highest dye sorption capacity(60.91μmol dye stuffs/g)with kinetic rate 8.22×10^-3 min^-1 in 90 min via multi-layer physisorption(Freundlich isotherm)on graphene *** additions,AlZnO@CN offered the highest photo-kinetic rate(Kphoto)of^54.1×10^-3 min^-1(93.8%after 60 min)under direct ***,the selective radical trapping experiment confirmed that the holes and oxidative superoxide radicals are crucial on dyes photodegradation *** to their superior performance,AlZnO@G and AlZnO@CN nanocomposites can offer an effective in-situ solar-assisted adsorption/photocatalytic remediation of textile wastewater effluents.

关键词： Carbon nanomaterials AlZnO photocatalyst Hybrid adsorption/photo-catalysis Kinetic and isotherm modeling Textile wastewater remediation

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愿中古友谊继续火热和甜蜜

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国际人才交流 2024年第4期 57-59页

作者：亚瑟·佩雷拉·尼格林永州(中国古巴)生物技术联合创新中心

有很多人问我:“为什么来中国?”我的回答是:“为什么不来中国!”我是来自古巴的yasser Perera Negrin,很多湖南朋友称呼我亚瑟。我一直对其他国家和文化很好奇,现在我所知道的大部分都是通过读书和看电影了解的。记得第一次深入了解中... 详细信息

有很多人问我:“为什么来中国?”我的回答是:“为什么不来中国!”我是来自古巴的yasser Perera Negrin,很多湖南朋友称呼我亚瑟。我一直对其他国家和文化很好奇,现在我所知道的大部分都是通过读书和看电影了解的。记得第一次深入了解中国的文化,就是从一本非常著名的书--中国古代军事家孙武的《孙子兵法》开始的。在这本书中我学到了很多可运用到现实生活中的知识经验,令我受益匪浅。

关键词：现实生活深入了解《孙子兵法》受益匪浅

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