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Identification of three major Bemisia tabaci biotypes in China based on morphological and DNA polymorphisms

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Progress in Natural Science:Materials International 2009年第6期19卷 713-718页

作者： Muhammad z.ahmed Vartika Mathur Department of Entomology South China Agricultural University Department of zoology Sri Venkateswara CollegeUniversity of Delhi

The sweet potato whitefly, Bemisia tabaci, is a complex species, and many of its biotypes are important agricultural pests. The B and Q biotypes are invasive and coexist with the native Cv biotype on vegetable and ornamental crops in China. In this study, these three bio- types were identified based on their morphological characteristics, RAPD-PCR analysis, and DNA sequences of the COI gene. The ante-rior and posterior wax fringes of the B, Q, and Cv biotypes significantly differed from each other. Based on this morphological characteristic, the three biotypes can easily be distinguished in greenhouses and fields. Genomic DNA RAPD-PCR band patterns also revealed differences between these biotypes using the H16 primer. The B biotype has three bright DNA bands between 250 and 600 bp, the Q biotype only has one bright band at 300 bp, while the Cv biotype has no band between 250 and 500 bp. Both the Cv and Q biotypes have two bright bands at 750 and 1000 bp while the B biotype has only one band at 1000 bp. Based on the COI gene, the genetic identity between B and Cv, B and Q, and Q and CV was 85.8%, 94.7%, and 86.0%, respectively. The MP tree indicated that the phylogenetic relationship between the B and Q biotypes is much closer than that between the B and Cv or the Q and Cv biotypes. The uses of the morphological, RAPD-PCR, and DNA sequencing methods in biotype identification of B. tabaci are discussed.

关键词： Bemisia tabaci complex Biotype DNA polymorphism Identification Morphology

Investigating energy policies to boost grid-connected rooftop solar PV in Sudan

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Clean Energy 2023年第5期7卷 994-1005页

作者： Tarig z.ahmed Ayah Mohamed Mawahib Eltayeb ahmed ahmed Osman Elamin Abdalgader Mohamed G.Hassan-Sayed Cambridge Institute for Sustainability Leadership(CISL) University of CambridgeCambridgeCB21QAUK Energy and Climate Change Division Faculty of Engineering and Physical ScienceThe University of SouthamptonSouthamptonSO171BJUK Institute of Engineering Research and Material Technology National Centre for ResearchKhartoumSudan/University of KhartoumSudan University of California Davis1 Shields AveDavisCA 95616USA School of Chemistry Faculty of Engineering and Physical SciencesThe University of SouthamptonSouthamptonSO171BJUK

Grid-connected rooftop solar photovoltaic(PV)systems can reduce the energy demand from the grid and significantly increase the power available to ***,rooftop solar PV has not yet been widely adopted in many sub-Saharan African countries,such as Sudan,although they are endowed with high solar radiation and in dire need of additional *** paper investigates risks and policies to increase grid-connected rooftop solar PV adoption in Sudan.A simplified United Nations Development Program Derisking Renewable Energy Investment framework is adopted to investigate this over three *** Stage 1,a list of risks and barriers was produced based on a literature review of solar PV studies in Sudan and interviews with nine *** was the risk most often mentioned(eight times from nine interviewees),followed by concerns about poor utility grid *** Stage 2,policy de-risking instruments and financial de-risking instruments were listed to overcome the *** include the intro-duction of net metering,the use of a third-party organization to monitor policy implementation,upgrade of the grid infrastructure,public awareness campaigns and energy-saving *** Stage 3,the levelized cost of electricity was estimated for a typical 2-kW rooftop PV system without policies(0.11$/kWh)and with a net-metering policy(0.07$/kWh).

关键词： energy policy rooftop solar PV Sudan energy poverty sustainable development photovoltaics

Determination of gamma ray spectrometry efficiency for the attenuation coefficients of some bismuth borate glasses by MCNP and(ISOCS)techniques

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Radiation Detection Technology and Methods 2018年第2期2卷 67-74页

作者： ahmed Y.El-Haseib z.ahmed Yasser B.Saddeek Radiation Safety Department Egyptian Nuclear and Radiological Regulatory Authority(ENRRA)Nasr CityCairoEgypt Nuclear Safeguards and Physical Protection Department Egyptian Nuclear and Radiological Regulatory Authority(ENRRA)Nasr CityCairoEgypt Physics Department Faculty of ScienceAl-Azhar UniversityAssiut 71524Egypt

Background Radiation detection has been a main interest for researchers as all kind of produced particles in atomic and subatomic physics based on the measurement systems so-called *** efficiency is one of the main parameters in detection system besides many other different parameters of the *** detector in experimental physics is an instrument that converts radiation energy into an electrical signal,and this is achieved basically by either ionization or *** choice for any type of a detector(gas-filled,scintillation or semiconductor)for any application depends upon the X-ray of gamma energy range of interest.A working model is therefore developed which is capable of describing the overall NaI(Tl)detection efficiency as a function of several known *** The attenuation coefficients for the bismuth borate glasses with different concentrations were measured using gamma spectroscopy *** numerical absolute efficiency calibration of a detector can be determined by In-Situ Object Calibration Software(ISOCS)and Monte Carlo Neutral Particle version 5(MCNP5)techniques which does not require any calibration standards or reference *** By using the ISOCS and MCNP5 methodologies,the full energy peak efficiency of a scintillator detector(3“X3”NaI(Tl))exposed to Co-60 and Cs-137 gamma ray sources with average accuracy range 0.126–1.224%for the used samples can be *** used materials are ternary and are located between the detector and the source to determine the attenuation coefficients for these samples by using the calculated full energy peak efficiencies of a *** The average accuracy ranged from−1.808 to 1.960%for linear attenuation coefficient(μ),while it ranged from−1.999 to 1.888%and from−1.924 to 1.960%for half value layer(HVL)and mass linear attenuation coefficient(μm),*** The calculated values of the absolute full energy peak efficiency have been used to determi

关键词： Detection efficiency Sodium iodine(NaI) Linear attenuation coefficient(μ) Mass linear attenuation coefficient(μm) Half-value layer(HVL)

Prediction of pressure gradient and hold-up in horizontal liquid-liquid pipe flow

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Petroleum Science 2023年第6期20卷 3766-3782页

作者： syed Amjad ahmed Bibin John School of Mechanical Engineering Vellore Institute of TechnologyIndia Department of Mechanical Engineering C Abdul Hakeem College of Engineering&TechnologyIndia

This paper aims to propose correlations to predict pressure gradient,friction factor and fluid phase hold-up in liquid-liquid horizontal pipe *** develop the correlations,experiments are conducted using high viscous oils(202 and 630 mPa⋅s)in a steel pipe of length 11.25 m and length-to-diameter ratio of *** addition,the experimental data from the literature comprising wide range of flow and fluid properties is *** the analysis,the liquid-liquid pipe flow data is categorized into two as:stratified and *** existing friction factor correlations are modified to incorporate the effects of viscosity of the oil phase,interfacial curvature(contact/wetting angle-in lieu of material of the pipe)and fluid phase *** the two-fluid model of stratified flow,the wall stress and interfacial stress correlations are substituted with superficial velocities of fluids and superficial Reynolds numbers of fluid phases replacing fluid phase velocities and fluid Reynolds ***,for dispersed flow,an effective Reynolds number is described as the sum of superficial Reynolds number of oil and water *** the generally employed mean or mixture Reynolds number with the effective Reynolds number into the existing single-phase turbulent flow friction factor correlation,an effective friction factor for oil-water flow is *** the proposed correlations,the pressure gradient across the oil-water flow and hold-up volume fraction are predicted with significant reduction in error compared with that of conventionally employed *** average error and standard deviation values of−7.06%,20.72%and 0.31%,18.79%are found for stratified flow and dispersed flow respectively.

关键词： oil-water flow two-fluid model pressure gradient stratified flow dispersed flow

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Survey and technological analysis of laser and its defense applications

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Defence Technology（防务技术） 2021年第2期17卷 583-592页

作者： syed Affan ahmed Mujahid Mohsin syed Muhammad zubair Ali Department of Avionics Engineering-College of Aeronautical Engineering(CAE) National University of Sciences and Technology(NUST)RisalpurKPKPakistan

The laser technology has made remarkable progress over the past couple of *** is being widely employed in diverse domains,such as holography,space sciences,spectroscopy,medical sciences,micro and power electronics,industrial engineering,and most distinctively,as directed energy military *** to their active transmissions,laser systems are similar to microwave radars to some extent;however,unlike conventional radars,the laser operates at very high frequencies thus making it a potent enabler of narrow-beam and high energy aerial deployments,both in offensive and defensive *** modern avionics systems,laser target indicators and beam riders are the most common devices that are used to direct the Laser Guided Weapons(LGW)accurately to the ground ***,compact size and outstanding angular resolution of laser-based systems motivate their use for drones and unmanned aerial ***,the narrow-beam divergence of laser emissions offers a low probability of intercept,making it a suitable contender for secure transmissions and safety-critical ***,the developments in space sciences and laser technology have given synergistic potential outcomes to use laser systems in space *** paper comprehensively reviews laser applications and projects for strategic defense actions on the ground or in ***,a detailed analysis has been done on recent advancements of the laser technology for target indicators and *** also reviews the advancements in the field of laser communications for surveillance,its earlier state of the art,and ongoing scientific research and advancements in the domain of high energy directed laser weapons that have revolutionized the evolving military *** offering a comprehensive taxonomy,the paper also critically analyzes some of the recent contributions in the associated domains.

关键词： Laser systems Laser military applications Directed energy weapons Non-lethal weapons Laser military projects Survey Taxonomy

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Nickel-titanium shape memory alloys made by selective laser melting:a review on process optimisation

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Advances in Manufacturing 2022年第1期10卷 24-58页

作者： Omar ahmed Mohamed syed Hasan Masood Wei Xu School of Engineering Deakin UniversityGeelongVIC 3216Australia Department of Mechanical Engineering The Higher Institute of Engineering TechnologyBani WaledLibya Department of Mechanical and Product Design Engineering Swinburne University of TechnologyHawthornVIC 3122Australia

Selective laser melting(SLM)is a mainstream powder-bed fusion additive manufacturing(AM)process that creates a three-dimensional(3D)object using a high power laser to fuse fine particles of various metallic powders such as copper,tool steel,cobalt chrome,titanium,tungsten,aluminium and stainless *** the past decade,SLM has received significant attention due to its capability in producing dense parts with superior mechanical *** a premier shape memory alloy,the nickel-titanium(NiTi)shape memory alloy is attractive for a variety of biomedical applications due to its superior mechanical properties,superelasticity,corrosion resistance and *** paper presents a comprehensive review of the recent progress in NiTi alloys produced by the SLM process,with a particular focus on the relationship between processing parameters,resultant microstructures and *** research gaps,challenges and suggestions for future research are also addressed.

关键词： Additive manufacturing(AM) Selective laser melting(SLM) Microstructure NiTi alloy Mechanical properties

Fingerprint matching,spoof and liveness detection:classification and literature review

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Frontiers of Computer Science 2021年第1期15卷 179-196页

作者： syed Farooq ALI Muhammad Aamir KHAN ahmed Sohail ASLAM Department of Software Engineering University of Management and TechnologyLahore 54770Pakistan Department of Informatics and Systems University of Management and TechnologyLahore 54770Pakistan Department of Computer Science University of Management and TechnologyLahore 54770Pakistan

Fingerprint matching,spoof mitigation and liveness detection are the trendiest biometric techniques,mostly because of their stability through life,uniqueness and their least risk of *** recent decade,several techniques are presented to address these challenges over well-known *** study provides a comprehensive review on the fingerprint algorithms and techniques which have been published in the last few *** divides the research on fingerprint into nine different approaches including feature based,fuzzy logic,holistic,image enhancement,latent,conventional machine learning,deep learning,template matching and miscellaneous *** these,deep learning approach has outperformed other approaches and gained significant attention for future *** reviewing fingerprint literature,it is historically divided into four eras based on 106 referred papers and their cumulative citations.

关键词： computer society template matching fingerprint recognition survey deep learning machine learning

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Modeling, analysis, and optimization of dimensional accuracy of FDM-fabricated parts using definitive screening design and deep learning feedforward artificial neural network

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Advances in Manufacturing 2021年第1期9卷 115-129页

作者： Omar ahmed Mohamed syed Hasan Masood Jahar Lal Bhowmik School of Engineering Deakin UniversityGeelongAustralia Department of Mechanical Engineering Higher Institute of Engineering TechnologyBani WalidLibya Department of Mechanical and Product Design Engineering Swinburne University of TechnologyHawthornVIC 3122Australia Department of Health Science and Biostatistics Swinburne University of TechnologyHawthornVIC 3122Australia

Additive manufacturing(AM)technologies such as fused deposition modeling(FDM)rely on the quality of manufactured products and the process ***,the dimensional accuracy and stability of any AM process is essential for ensuring that customer specifications are satisfied at the highest standard,and variations are controlled without significantly affecting the functioning of processes,machines,and product *** study aims to investigate the effects of FDM fabrication conditions on the dimensional accuracy of cylindrical *** this study,a new class of experimental design techniques for integrated second-order definitive screening design(DSD)and an artificial neural network(ANN)are proposed for designing experiments to evaluate and predict the effects of six important operating *** determining the optimum fabrication conditions to obtain better dimensional accuracies for cylindrical parts,the time consumption and number of complex experiments are reduced considerably in this *** optimum fabrication conditions generated through a second-order DSD are verified with experimental *** results indicate that the slice thickness,part print direction,and number of perimeters significantly affect the percentage of length difference,whereas the percentage of diameter difference is significantly affected by the raster-to-raster air gap,bead width,number of perimeters,and part print ***,the results demonstrate that a second-order DSD integrated with an ANN is a more attractive and promising methodology for AM applications.

关键词： Artificial neural network(ANN) OptimizationDefinitive screening design(DSD) Analysis of variance(ANOVA) Fused deposition modeling(FDM) Dimensional accuracy

Optical and electrical nano eco-sensors using alternative deposition of charged layer

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Frontiers of Materials Science 2011年第1期5卷 40-49页

作者： syed Rahin ahmed Seong Cheol HONG Jaebeom LEE Department of Nanomedical Engineering College of Nanoscience and Nanoengineering Pusan National University Miryang 627-709 Korea

This review focuses on layer by layer （LBL） assembly-based nano ecological sensor （hereafter, eco-sensor） for pesticide detection, which is one of the most versatile methods. The effects of pesticides on human health and on the environment （air, water, soil, plants, and animals） are of great concern due to their increasing use. We highlight two of the most popular detecting methods, i.e., fluorescence and electrochemical detection of pesticides on an LBL assembly. Fluorescence materials are of great interest among researchers for their sensitivity and reliable detection, and electrochemical processes allow us to investigate synergistic interactions among film components through charge transfer mechanisms in LBL film at the molecular level. Then, we noted some prospective directions for development of different types of sensing systems.

关键词： pesticides fluorescence electrochemistry layer by layer (LBL)