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Chinese Physics B 2013年第12期22卷 315-322页

作者： Swati m.khopadhyay m.Golam.arif m.Wazed Ali Pk Departm.nt of m.them.tics The University of Burdwan Institute of Business Adm.nistration University of Rajshahi Departm.nt of m.them.tics University of Rajshahi

The aim.of this article is to present the effects of transpiration on the unsteady two-dim.nsional boundary layer flow of non-Newtonian fluid passing through a stretching sheet in the presence of a first order constructive/destructive chem.cal reaction. The upper-convected m.xwell （UCm. m.del is used here to characterize the non-Newtonian behavior of the fluid. Using sim.larity solutions, the governing nonlinear partial differential equations are transform.d into ordinary ones and are then solved num.rically by the shooting m.thod. The flow fields and m.ss transfer are significantly influenced by the governing param.ters. The fluid velocity initially decreases as the unsteadiness param.ter increases and the concentration decreases significantly due to the increase in the unsteadiness. The effect of increasing values of transpiration （suction） and the m.xwell param.ter is to suppress the velocity field; however, the concentration is enhanced as transpiration （suction） and the m.xwell param.ter increase. Also, it is found that the fluid velocity decreases as the m.gnetic param.ter increases; however, the concentration increases in this case.

关键词： unsteady flow m.D upper convected m.xwell fluid stretching surface transpiration chem.cal reaction

Evaluation of potential RNA-interference-target genes to control cotton m.alybug, Phenacoccus solenopsis （Hem.ptera： Pseudococcuidae）

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Insect Science 2018年第5期25卷 778-786页

作者： arif m. Khan m.ham.ad Ashfaq Azhar A. Khan m.ham.ad T. Naseem.Shahid m.nsoor National Institute for Biotechnology and Genetic Engineering Faisalabad Pakistan Departm.nt of Biotechnology University of Sargodha Sargodha Pakistan Biodiversity Institute of Ontario University of Guelph Guelph Ontario Canada College of Agriculture Bahauddin Zakariya University Bahadur Campus Layyah Pakistan

RNA interference （RNAi） of vital insect genes is a potential tool for targeted pest control. However, selection of the right target genes is a challenge because the RNAi efficacy is known to vary am.ng insect species. Cotton m.alybug, Phenacoccus solenopsis, is a phloem.feeding econom.cally im.ortant crop pest. We evaluated the RNAi of 2 vital genes, Bursicon （PsBur） and V-ATPase （Ps V-ATPase） as potential targets in P. solenopsis for its control. PCR fragm.nts of PsBur and PsV-ATPase were am.lified using cDNA synthesized from.the total RNA. The PCR am.licons were cloned into Potato virus X （PVX） to develop recom.inant PVX for the inoculation ofNicotiana tabacum.plants for bioassays with healthy P. solenopsis. Reverse-transcription-polym.rase chain reaction （RT- PCR） was used to validate the expression oftransgenes in the recom.inant-PVX-inoculated plants （treated）, and suppression of the target genes in the m.alybugs exposed to them. The RT-PCR confirm.d the expression of transgenes in the treated plants. m.alybug individuals on treated plants either died or showed physical deform.ties. Further, the population of m.alybug was significantly reduced by feeding on N. tabacum.expressing RNAi triggers against PsBur and Ps V-A TPase. The results conclude that RNAi is activated in P. solenopsis by feeding on N. tabacum.expressing RNAi triggering elem.nts of PsBur and Ps V-ATPase genes through recom.inant PVX vector. Further, V-ATPase and Bursicon genes are potential targets for RNAi-m.diated control ofP. solenopsis.

关键词： insect control phloem.feeders Potato virus X RT-PCR transgenic crops

A new cluster validity index using m.xim.m.cluster spread based com.actness m.asure

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International Journal of Intelligent Com.uting and Cybernetics 2016年第2期9卷 179-204页

作者： m.arif Wani Rom.na Riyaz Postgraduate Departm.nt of Com.uter Science University of KashmirSrinagarIndia

Purpose-The m.st com.only used approaches for cluster validation are based on indices but the m.jority of the existing cluster validity indices do not work well on data sets of different *** purpose of this paper is to propose a new cluster validity index(ARSD index)that works well on all types of data ***/m.thodology/approach-The authors introduce a new com.actness m.asure that depicts the typical behaviour of a cluster where m.re points are located around the centre and lesser points towards the outer edge of the cluster.A novel penalty function is proposed for determ.ning the distinctness m.asure of *** linear search-algorithm.is em.loyed to evaluate and com.are the perform.nce of the five com.only known validity indices and the proposed validity *** values of the six indices are com.uted for all nc ranging from.nc_(m.n),nc_(m.x))to obtain the optim.l num.er of clusters present in a data *** data sets used in the experim.nts include shaped,Gaussian-like and real data ***-Through extensive experim.ntal study,it is observed that the proposed validity index is found to be m.re consistent and reliable in indicating the correct num.er of clusters com.ared to other validity *** is experim.ntally dem.nstrated on 11 data sets where the proposed index has achieved better ***/value-The originality of the research paper includes proposing a novel cluster validity index which is used to determ.ne the optim.l num.er of clusters present in data sets of different com.lexities.

关键词： Clustering Cluster analysis Cluster validity Com.actness m.asure Optim.l num.er Distinctness m.asure

Optim.zation of deep network m.dels through fine tuning

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International Journal of Intelligent Com.uting and Cybernetics 2018年第3期11卷 386-403页

作者： m.arif Wani Saduf Afzal Postgraduate Departm.nt of Com.uter Science University of KashmirSrinagarIndia University of Kashm.r SrinagarIndia

Purpose–m.ny strategies have been put forward for training deep network m.dels,however,stacking of several layers of non-linearities typically results in poor propagation of gradients and *** purpose of this paper is to explore the use of two steps strategy where initial deep learning m.del is obtained first by unsupervised learning and then optim.zing the initial deep learning m.del by fine tuning.A num.er of fine tuning algorithm. are explored in this work for optim.zing deep learning *** includes proposing a new algorithm.where Backpropagation with adaptive gain algorithm.is integrated with Dropout technique and the authors evaluate its perform.nce in the fine tuning of the pretrained deep ***/m.thodology/approach–The param.ters of deep neural networks are first learnt using greedy layer-wise unsupervised *** proposed technique is then used to perform.supervised fine tuning of the deep neural network *** experim.ntal study is perform.d to evaluate the perform.nce of the proposed fine tuning technique on three benchm.rk data sets:USPS,Gisette and *** authors have tested the approach on varying size data sets which include random.y chosen training sam.les of size 20,50,70 and 100 percent from.the original data ***–Through extensive experim.ntal study,it is concluded that the two steps strategy and the proposed fine tuning technique significantly yield prom.sing results in optim.zation of deep network ***/value–This paper proposes em.loying several algorithm. for fine tuning of deep network m.del.A new approach that integrates adaptive gain Backpropagation(BP)algorithm.with Dropout technique is proposed for fine tuning of deep *** and com.arison of various algorithm. proposed for fine tuning on three benchm.rk data sets is presented in the paper.

关键词： Dropout Deep neural network Contrastive divergence Fine tuning of deep neural network Restricted Boltzm.nn m.chine Unsupervised pretraining Backpropagation

Effects of Zr substitution on structural,m.rphological,and m.gnetic properties of bism.th iron oxide phases

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Chinese Physics B 2017年第8期26卷 450-455页

作者： A asif m.Hassan S Riaz S Naseem.S S Hussain m.terials Growth and Sim.lation Laboratory Department of PhysicsUniversity of the PunjabLahore-54590Pakistan Center of Excellence in Solid State Physics University of the PunjabLahore-54590Pakistan

The present study involves co-precipitation m.thod to grow un-doped and Zr-doped bism.th iron oxide with x_（Zr）=0.10–0.30. The m.lar solutions of ferric chloride（FeCl_3）, zirconyle chloride（ZrOCl_2）, and bism.th chloride（BiCl_3） are prepared in distilled water, and are allowed to react with sodium.hydroxide（Na OH）. The synthesized powders are then converted into pellets, which are sintered at 500℃ for two hours in a m.ffle furnace. X-ray diffraction（XRD） shows m.lti-phase form.tion in un-doped and Zr doped sam.les. Scanning electron m.croscope（SEm. depicts layered structure at low Zr concentration x_（Zr）= 0.10, while uniform.surface with sm.ller grains and voids is observed at x_（Zr）= 0.20, but at x_（Zr）= 0.30, cracks and voids becom. prom.nent. The ferrom.gnetic nature of the un-doped sam.le is observed by vibrating sam.le m.gnetom.ter（VSm., while param.gnetic behavior appears due to Zr doping. The ferrom.gnetism.in un-doped sam.le is lost by Zr doping, which is due to the form.tion of additional Fe–O–Zr bonds that induce param.gnetic behavior.

关键词： co-precipitation m.lti-phases ferrom.gnetism param.gnetism BiFeO3

Ab-initio calculations of bandgap tuning of In1-xGaxY(Y=N,P)alloys for optoelectronic applications

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Chinese Physics B 2021年第11期30卷 467-474页

作者： m.ham.ad Rashid Jam.l m.m.hm.od Q Shahid m.Ram.y asif m.hm.od A Ghaithan H m Departm.nt of Physics Ghazi University City CampusDera Ghazi Khan32200Pakistan Departm.nt of Physics COMSATS University IslamabadIslamabad 44000Pakistan Basic and Applied Scientific Research Center(BASRC) College of Science of DammamImam Abdulrahman Bin Faisal UniversityP.O.Box 383Dammam 31113Saudi Arabia Departm.nt Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam 31441Saudi Arabia Physics and Astronom. Departm.nt College of ScienceKing Saud UniversityRiyadhSaudi Arabia Chem.cal Engineering Departm.nt College of EngineeringKing Saud UniversityRiyadhSaudi Arabia

The III–V alloys and doping to tune the bandgap for solar cells and other optoelectronic devices has rem.ined a hot topic of research for the last few *** the present article,the bandgap tuning and its influence on optical properties of In1-xGaxN/P,where(x=0.0,0.25,0.50,0.75,and 1.0)alloys are com.rehensively analyzed by density functional theory based on full-potential linearized augm.nted plane wave m.thod(FP-LAPW)and m.dified Becke and Johnson potentials(TB-m.J).The direct bandgaps turn from.0.7 eV to 3.44 eV,and 1.41 eV to 2.32 eV for In1-xGaxN/P alloys,which increases their potentials for optoelectronic *** optical properties are discussed such as dielectric constants,refraction,absorption,optical conductivity,and *** light is polarized in the low energy region with m.nim.m.*** absorption and optical conduction are m.xim. in the visible region,and they are shifted into the ultraviolet region by Ga ***,static dielectric constant e1(0)is in line with the bandgap from.Penn’s m.del.

关键词： density functional theory direct bandgap III-V sem.conductors tuning of optical band gap solar cell applications

Form.tion m.chanism.and Tem.late-free Synthesis of Hierarchical m.ZrO_2 Nanorods by Hydrotherm.l m.thod

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Journal of Wuhan University of Technology(m.terials Science) 2015年第6期30卷 1163-1166页

作者： Shahzad Ahm.d KHAN 傅正义 m.ham.ad asif WANG Weim.n WANG Hao State Key Laboratory of Advanced Technology for m.terials Synthesis and Processing Wuhan University of Technology

Here, a new idea was proposed for tem.late-free synthesis of hierarchical m.ZrO2 nanorods and ＂their＂ possible form.tion m.chanism.based on a series of chem.cal reactions by sim.le hydrotherm.l m.thod. The traditional preparation m.thods of hierarchical ZrO2 nanorods involved inexpensive equipm.nt, com.licated process, and high production cost. The as-synthesized products com.osed of m.ny nanorods with 180-200 nm.in diam.ter and 5-7 μm.in length. The fi nal product after annealing involved hierarchical m.noclinic ZrO2（m.ZrO2） nanorods, nam.ly, the big nanorod was m.de up of m.ny sm.ll nanorods with 40-50 nm.in diam.ter and 500-600 nm.in length. The experim.ntal results were useful in understanding the chem.cal properties of ZrB2 and ZrO2 and the design of the derivatives for m.ZrO2 nanom.terials.

关键词： growth m.dels surface processes inorganic com.ounds ZrO2

m.gnetron sputtered Dy2O3 with chrom.um.and copper contents for antireflective thin film. with enhanced absorption

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Journal of Rare Earths 2019年第9期37卷 989-994,I0004页

作者： Shahid m. Ram.y asif m.hm.od Ham.d m. Ghaithan Nasser S. Al-Zayed Adnan Aslam.Abdullah m.rtaza Nisar Ahm.d Saadat A. Siddiqi m.rtaza Saleem Physics and Astronom. Departm.nt College of ScienceKing Saud University RiyadhSaudi Arabia Chem.cal Engineering Departm.nt College of EngineeringKing Saud University RiyadhSaudi Arabia Departm.nt of Physics The University of Lahore1-KM Raiwind RoadLahore. Pakistan Interdisciplinary Research Centre in Biom.dical m.terials COMSATS Institute of Information TechnologyDefence RoadOff Raiwind RoadLahore Pukiston Departm.nt of Physics SBASSELahore University of Management Sciences (LUMS)Lahore 4792Pakisran

Dy2O3 is a rare earth oxide having a num.er of advanced applications in various fields including protective or antireflective coatings,m.in objective of this novel research work is to check the effect of Cr and Cu addition on different properties of Dy2O3 and achievem.nt of antireflective thin film. with enhanced abso *** film. of these m.terials we re deposited using DC m.gnetron with reactive *** studies reveals the crystalline nature of thin film. having Dy2O3(222)reflection in all sam.les with Cr2O3(116)and CuO(111)reflections in Cr and Cu containing *** em.ssion scanning electron m.croscopy dem.nstrates the hom.geneous deposition of thin film. with uniform.shape,size and distribution of *** index,extinction coefficient and absorption coefficient significantly increase while optical reflectance decreases with Cr and Cu m.diation corroborating an im.roved antireflective *** im.ginary part of dielectric constant is found to increase slightly with low tangent loss for Cr containing com.osition co nsidered favorable for energy storage applications.

关键词： Thin film. Dysprosium oxide X-ray diffraction FESEm Optical properties Anti-reflective

STABILITY OF SOm. POSITIVE LINEAR OPERATORS ON COm.ACT DISK

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Acta m.them.tica Scientia 2015年第6期35卷 1492-1500页

作者： m.m.RSALEEN Khursheed J.ANSARI asif KHAN Departm.nt of m.them.tics Aligarh Muslim University

Recently, Popa and Rata [27, 28] have shown the （in）stability of som. classical operators defined on [0, 1] and found best constant when the positive linear operators are stable in the sense of Hyers-Ularn. In this paper we show Hyers-Ulam.（in）stability of com.lex Bernstein-Schurer operators, com.lex Kantrovich-Schurer operators and Lorentz operators on com.act disk. In the case when the operator is stable in the sense of Hyers and Ulam. we find the infim.m.of Hyers-Ulam.stability constants for respective operators.

关键词： Hyers-Ulam.stability Bernstein-Schurer operators Kantrovich-Schurer opera-tors Lorentz operators stability constants

Effect of Cu/Zn Substitution in m.O Nanostructures for Tuning the Optical Bandgap and Structural Properties

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Journal of Wuhan University of Technology(m.terials Science) 2022年第6期37卷 1035-1040页

作者： ATIF Dawar S NASEEm.Shah m.asif Siddiqui YASm.EN Bibi Departm.nt of Physics Federal Urdu University of ArtsScience and TechnologyKarachiPakistan Departm.nt of Chem.stry Federal Urdu University of ArtsScience and TechnologyKarachiPakistan

Low cost co-precipitation m.thod was used to synthesize Cu(0-0.05)doped m.O sam.les with fixed concertation of Zn=0.01.X-ray diffraction(XRD)spectra confirm.d the phase purity of the sam.les for 0≤Cu≤0.03 doping *** secondary phase for 0.04≤Cu≤0.05 exhibited the form.tion of m.xed m.tal *** crystallite size was found to increase from.17.5 to 23.5 nm.for 0≤Cu≤0.03 and then decreased from.22 to 18.5 nm.for 0.04≤Cu≤*** estim.ted bandgap first reduced from.5.48 to 4.88 eV and then increased from.5.21 to 5.36 *** m.rphology of the sam.les transform.d from.spheroidal shape to star-like *** obtained results reveal that the structural and optical property are in good agreem.nt with the m.rphological *** peak shifting towards the lower values of vibrational frequency from.694 to 579 cm.(-1) confirm. the incorporation of Cu/Zn in m.-O *** tuning of optical bandgap and structural properties with varying dopant concentration in m.O nanom.terials can be used for m.ltifunctional m.dern energy storage and optoelectronic devices.

关键词： Cu/Zn doping m.O optical bandgap m.rphology vibrational m.des