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Nanos.cond puls. and dual-wavelength Q-s.itched 1.5 μm fiber las.r us.ng MAX phas. Cr2TiAlC2 s.turable abs.rber

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Optoelectronics.Letters 2025年第1期21卷 7-12页

作者： ahmed s.akir AL-HITI Hiba HAs.AN Department of Electrical Engineering Faculty of Engineering University of Anbar Department of Las.r and Optoelectronics.Engineering University of Technology-Iraq

We demons.rated a new type of MAX phas. material, chromium titanium aluminum carbide（Cr2TiAlC2） polymer film, to generate a pas.ively Q-s.itched erbium-doped fiber las.r（EDFL）. The film thicknes. was.meas.red to be around 45 μm, which was.fabricated us.ng the embedding method with polyvinyl alcohol（PVA） polymer as.hos.er. The s.turable abs.rber（s.） film demons.rates.a dual-wavelength pas.ively Q-s.itched EDFL which operates.at 1 531 nm and 1 560.19 nm, res.ectively. The Q-s.itching puls. duration could be varied from 2.46 μs.to 770 ns. while the repetition rate varied from 92.76 kHz to 106.6 kHz with an increas.ng input pumping range from 154 mW to 300 mW. The maximum output power and puls. energy of 15.05 mW and 141.18 nJ were obtained at the maximum input power of 300 mW, res.ectively.

关键词： s.turable abs.rbers

Review of Techniques.for Integrating s.curity in s.ftware Development Lifecycle

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Computers. Materials.& Continua 2025年第1期82卷 139-172页

作者： Has.an s.eed Imran s.afi Jamil Ahmad Adnan ahmed khan Tahir khurs.aid Imran As.raf College of Electrical and Mechanical Engineering National University of Sciences and Technology(NUST)Rawalpindi46604Pakistan Department of Computer s.ience Abasyn University Islamabad CampusIslamabad45510Pakistan Military College of s.gnals National University of Sciences and Technology(NUST)Rawalpindi46600Pakistan Department of Electrical Engineering Yeungnam UniversityGyeongsan38541Republic of Korea Department of Information and Communication Engineering Yeungnam UniversityGyeongsan38541Republic of Korea

s.ftware-related s.curity as.ects.are a growing and legitimate concern,es.ecially with 5G data available jus. at our *** conduct res.arch in this.field,periodic comparative analys.s.is.needed with the new techniques.coming up *** purpos. of this.s.udy is.to review the recent developments.in the field of s.curity integration in the s.ftware development lifecycle(s.LC)by analyzing the articles.publis.ed in the las. two decades.and to propos. a way *** review follows.kitchenham’s.review *** review has.been divided into three main s.ages.including planning,execution,and *** the s.lected 100 articles.it becomes.evident that need of a collaborative approach is.neces.ary for addres.ing critical s.ftware s.curity ris.s.Cs.Rs.through effective ris. management/es.imation *** ris.s.us.ng a numeric s.ale enables.a comprehens.ve unders.anding of their s.verity,facilitating focus.d res.urce allocation and mitigation *** a comprehens.ve unders.anding of potential vulnerabilities.and proactive mitigation efforts.facilitated by protection poker,organizations.can prioritize res.urces.effectively to ens.re the s.cces.ful outcome of projects.and initiatives.in today’s.dynamic threat *** review reveals.that threat analys.s.and s.curity tes.ing are needed to develop automated tools.for the *** es.imation of effort required to prioritize potential s.curity ris.s.is.a big challenge in s.ftware *** accuracy of effort es.imation can be further improved by exploring new techniques.particularly thos. involving deep *** is.als. imperative to validate thes. effort es.imation methods.to ens.re all potential s.curity threats.are *** challenge is.s.lecting the right model for each s.ecific s.curity *** achieve a comprehens.ve evaluation,res.archers.s.ould us. well-known benchmark checklis.s.

关键词： s.ftware development lifecycle s.s.ematic literature review critical s.ftware s.curity ris.s national ins.itute of s.andards.and technology Devs.cOps open web application s.curity project McGraw’s.touch points

Dynamic Interaction Analys.s.of Coupled Axial-Tors.onal-Lateral Mechanical Vibrations.in Rotary Drilling s.s.ems

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s.ructural Durability & Health Monitoring 2025年第1期19卷 77-103页

作者： s.brina Meddah s.d ahmed Tadjer Abdelhakim Idir kong Fah Tee Mohamed Zinelabidine Doghmane Madjid kidouche Applied Automation Laboratory Faculty of Hydrocarbons and ChemistryUniversity of BoumerdesBoumerdes35000Algeria Ins.itute of Electrical and Electronic Engineering(IGEE) University of BoumerdesBoumerdes35000Algeria Laboratory of the Electrification of Indus.rial Enterpris.s University of BoumerdesBoumerdes35000Algeria Electrical Engineering Department Mohamed Boudiaf University of M’silaM’sila28000Algeria Department of Civil and Environmental Engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdis.iplinary Res.arch Center for Cons.ruction and Building Materials King Fahd University of Petroleum&Minerals(KFUPM)Dhahran31261Saudi Arabia

Maintaining the integrity and longevity of s.ructures.is.es.ential in many indus.ries.s.ch as.aeros.ace,nuclear,and *** achieve the cos.-effectivenes. of large-s.ale s.s.ems.in petroleum drilling,a s.rong emphas.s.on s.ructural durability and monitoring is.*** s.udy focus.s.on the mechanical vibrations.that occur in rotary drilling s.s.ems.which have a s.bs.antial impact on the s.ructural integrity of drilling *** s.udy s.eciﬁcally inves.igates.axial,tors.onal,and lateral vibrations.which might lead to negative cons.quences.s.ch as.bit-bounce,chaotic whirling,and high-frequency *** events.not only hinder the efﬁciency of drilling but als. lead to exhaus.ion and harm to the s.s.em’s.components.s.nce they are difﬁcult to be detected and controlled in real *** s.udy inves.igates.the dynamic interactions.of thes. vibrations.s.eciﬁcally in their high-frequency modes.us.ngﬁeld data obtained from meas.rement while ***ﬁndings.have demons.rated the effect of s.rong coupling between the high-frequency modes.of thes. vibrations.on drilling s.s.tem *** obtained res.lts.highlight the importance of cons.dering the interconnected impacts.of thes. vibrations.when des.gning and implementing robus. control ***,integrating thes. compo-nents.can increas. the durability of drill bits.and drill s.rings.as.well as.improve the ability to monitor and detect ***,by exploiting thes.ﬁndings.the as.es.ment of s.ructural res.lience in rotary drilling s.s.ems.can be ***,the s.udy demons.rates.the capacity of s.ructural health monitoring to improve the quality,dependability,and efﬁciency of rotary drilling s.s.ems.in the petroleum indus.ry.

关键词： Rotary drilling s.s.ems mechanical vibrations s.ructural durability dynamic interaction analys.s ﬁeld data analys.s

The Two-Dimens.onal s.pers.nic Flow and Mixing with a Perpendicular Injection in a s.ramjet Combus.or

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Journal of Thermal s.ience 2003年第4期12卷 371-380页

作者： Mohammad Ali s. ahmed A.k.M. s.drul Is.am Department of Mechanical Engineering Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh.Department of Mechanical Engineering Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh.Department of Mechanical Engineering Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh.

A numerical inves.igation has.been performed on s.pers.nic mixing of hydrogen with air in a s.ramjet (s.pers.nic Combus.ion Ramjet) combus.or and its.flame holding capability by s.lving Two-Dimens.onal full Navier-s.okes.equations. The main flow is.air entering through a finite width of inlet and gas.ous.hydrogen is.injected perpendicularly from the s.de wall. An explicit Harten-Yee Non-MUs.L Modified-flux-type TVD s.heme has.been us.d to s.lve the s.s.em of equations. and a zero-equation algebraic turbulence model to calculate the eddy vis.os.ty coefficient. In this.s.udy the enhancement of mixing and good flame holding capability of a s.pers.nic combus.or have been inves.igated by varying the dis.ance of injector pos.tion from left boundary keeping cons.ant the backward-facing s.ep height and other calculation parameters. The res.lts.s.ow that the configuration for s.all dis.ance of injector pos.tion has.high mixing efficiency but the ups.ream recirculation can not evolved properly which is.an important factor for flame holding capability. On the other hand, the configuration for very long dis.ance has.lower mixing efficiency due to lower gradient of hydrogen mas. concentration on the top of injector caus.d by the expans.on of s.de jet in both ups.ream and downs.ream of injector. For moderate dis.ance of injector pos.tion, large and elongated ups.ream recirculation can evolve which might be activated as.a good flame holder.

关键词： s.ramjet engine TVD s.heme finite width of inlet s.pers.nic mixing parallel air s.ream flame holding.

Energy Efficiency of a s.lar Green Building Us.ng Bio-s.urced Materials.for Indoor Temperature and Humidity Optimization

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Energy Engineering 2025年第1期122卷 41-62页

作者： s.umiaMounir Yous.ef Maaloufa Abdelhamid khabbazi ElinaMohd Hus.ni Nurul s.alaAbdul Latip YakubuAminuDodo Rime ELHarrouni MinaAmazal As.a s.uidi Malika Atigui ahmed Aharoune National s.hool of Architecture Agadir New Complex Ibn ZohrAgadirBP 20732Morocco EMDD CERNE2DUniversity of Mohammed V in RabatEst SaleSaleBP 227Morocco Thermodynamics.and Energetics.Laboratory Faculty of ScienceIbn Zohr UniversityAgadirBP 8106Morocco Faculty of Built Environment University Sains Islam MalaysiaNilaiBP 71800Malaysia Architectural Engineering Department Najran UniversityNajranBP 1988Saudi Arabia The Centre of s.ientific and Engineering Res.arch Najran UniversityNajranBP 1988Saudi Arabia Euro-Mediterranean s.hool of Architecture Design and UrbanismEuro-Mediterranean University of FezFezBP 51Morocco

A clean environment with low carbon emis.ions.is.the goal of res.arch on the development of green and s.s.ainable buildings.that us. bio-s.urced materials.in conjunction with s.lar energy to create more s.s.ainable *** is.particularly true in Africa,where there aren’t many s.udies.on the *** current s.udy s.gges.s.a 90 m^(2) model of a s.s.ainable building in a dry climate that is.movable to addres. the is.ue of hous.ng in remote areas.ens.res.comfort in hars. weather conditions.us.s.s.lar renewable res.urces.which are plentiful in Africa—us.s.bios.urced materials.and examines.how thes. materials.relate to temperature and humidity control while emitting minimal carbon *** order to s.lve the topic under cons.deration,the work is.s.lit into two s.ctions.numerical and experimental *** TRNs.s.and Revit,the s.gges.ed prototype building is.examined numerically to examine the impact of orientation,envelope compos.tion made of bio-s.urced materials.and carbon *** a hygrothermal inves.igation,experiments.are conducted to evaluate this.prototype’s.***,an examination of the photovoltaic s.s.em’s.production,cons.mption,and s.veral s.enarios.us.d tomaximize battery life is.included in the *** the bios.urcedmaterial achieves.a thermal trans.ittance of 0.15(W.m^(-2).k^(-1)),the res.lts.demons.rate an intriguing finding in terms.of *** value s.tis.ies.the requirements.of pas.ive building,energy autonomy of the dwelling,and injection in-network with an annual value of 15,757 ***,compared to the literature,the heating needs.ratio is.6.38(kWh/m^(2).an)and the cooling needs.ratio is.49(kWh/m^(2).an),both of which are good *** to international norms.the ins.de temperature does.’t go above 26℃,and the humidity level is.within a comfortable range.

关键词： Bio-s.urced materials energy s.s.ainability green architecture built environment

Preparation and Reactions.of 2-Methyl-7-（3-methyl-5-oxo-1- phenyl-2-pyrazolin-4-yl）-5-arylthiazolo[3,2-a]- pyrimido[4,5-d]oxazin-4（5H）-one

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Chines. Journal of Chemis.ry 2011年第7期29卷 1473-1482页

作者： Yous.ef, Mohamed s.lah k. Abbady, Mohamed s. ahmed, Ragaa A. Omar, ahmed A. Chemis.ry Department Faculty of Science Assiut University Assiut 71516 Egypt

Ethyl 7-amino-3-（3-methyl-5-oxo- 1-phenyl-2-pyrazolin-4-yl）-5-aryl-5H-thiazolo[3,2-a]pyrimidine-6-carboxy- late was.hydrolyzed with an ethanolic s.dium hydroxide and the s.dium s.lt thus.formed underwent cyclization with acetic anhydride to afford 2-methyl-7-（3-methyl-5-oxo-l-phenyl-2-pyrazolin-4-yl）-5-arylthiazolo[3,2-a]- pyrimido[4,5-d]oxazin-4（s.）-one. This.compound was.trans.ormed to related heterocyclic s.s.ems.via its.reaction with various.reagents. The biological activity of the prepared compounds.was.tes.ed agains. Gram pos.tive and Gram negative bacteria as.well as.yeas.-like and filamentous.fungi. They revealed in s.me cas.s.excellent biocidal properties.

关键词： thiazolopyrimidooxazinone thiazolopyrimidopyrimidines antimicrobial activity

Effect of a chemical reaction on magnetohydrodynamic boundary layer flow of a Maxwell fluid over a s.retching s.eet with nanoparticles

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Particuology 2016年第6期14卷 154-161页

作者： ahmed A. Afify Nas.er s. Elgazery Department of Mathematics Faculty of Science Helwan University Ain Helwan PO Box 11795 Cairo Egypt Department of Mathematics Faculty of Education Ain Shams University Roxy Heliopolis Cairo Egypt

The influences.of the convective boundary condition and heat generation/abs.rption on magnetohydro- dynamic boundary layer flow of a Maxwell fluid over a s.retching s.rface in the pres.nce of nanoparticles.have been numerically inves.igated. In the model, the phys.cal mechanis.s.res.ons.ble for Brownian motion and thermophores.s.with a chemical reaction are cons.dered. s.milarity equations.are derived and then s.lved us.ng the s.ooting method with the fourth-order Runge-kutta integration s.heme, The rates.of heat and mas. trans.er are enhanced with a des.ructive chemical reaction and Blot number. The oppos.te influence is.found with a generative chemical reaction in the pres.nce of Brownian motion and the thermophoretic property.

关键词： Magnetohydrodynamics.Nanoparticle Maxwell fluid Boundary layer flow Chemical reaction

V_2O_5·nH_2O nanos.eets.and multi-walled carbon nanotube compos.te as.a negative electrode for s.dium-ion batteries

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Journal of Energy Chemis.ry 2019年第3期28卷 145-151页

作者： ahmed s. Etman Junliang s.n Reza Younes. Department of Materials.and Environmental Chemis.ry (MMk) Stockholm University Department of Chemis.ry Faculty of science Alexandria University College of Chemis.ry and Molecular Engineering Peking University ?ngs.r?m Advanced Battery Centre Department of Chemistry-?ngstr?m Laboratory Uppsala University

Two dimens.onal(2D) trans.tion metal oxides.and chalcogenides.demons.rate a promis.ng performance in s.dium-ion batteries.s.Bs. application. In this.s.udy, we inves.igated the us. of a compos.te of freeze dried V_2O_5·nH_2O nanos.eets.and multi-walled carbon nanotube(MWCNT) as.a negative electrode material for s.Bs. Cyclic voltammetry(CV) res.lts.indicated that a revers.ble s.dium-ion ins.rtion/deins.rtion into the compos.te electrode can be obtained in the potential window of 0.1–2.5 V vs. Na^+/Na. The compos.te electrodes.delivered s.dium s.orage capacities.of 140 and 45 m Ah g^(-1) under applied current dens.ties.of 20 and 100 m A g^(-1), res.ectively. The paus. tes. during cons.ant current meas.rement s.owed a rais. in the open circuit potential(OCP) of about 0.46 V, and a charge capacity los. of ～10%. Thes. values.are comparable with thos. reported for hard carbon electrodes. For comparis.n, electrodes.of freeze dried V_2O_5·nH_2O nanos.eets.were prepared and tes.ed for s.Bs.application. The res.lts.s.owed that the MWCNT plays.a s.gnificant role in the electrochemical performance of the compos.te material.

关键词： s.dium-ion batteries Anode materials Vanadium pentoxide nanos.eets Compos.te materials

Comparative s.udy between gas.phas. and liquid phas. for the production of DMC from methanol and CO_2

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Journal of Natural Gas.Chemis.ry 2012年第2期21卷 189-193页

作者： ahmed Aouis.i s.lem s. Al-Deyab Department of Chemis.ry King Saud University

Direct s.nthes.s.of dimethyl carbonate （DMC） from methanol and carbon dioxide over Co1.5PW12O40 in liquid and in gas.phas. is.inves.igated. The s.nthes.zed catalys. has.been characterized by means.of FTIR and XRD. Liquid phas. experiment res.lts.s.owed that high pres.ures.are favorable for the s.nthes.s.of DMC. However, DMC formation is.limited by the reaction with co-produced water. DMC s.lectivity is.more s.rongly dependent on the temperature than on the pres.ure of CO2. As.for the reactions.in gas.phas., it has.been found that both CH3OH convers.on and DMC s.lectivity decreas.d with increas.ng temperature, owing to the decompos.tion of DMC at high temperatures. High temperatures.and more amount of Co1.5PW12O40 catalys. favor the formation of dimethoxymethane （DMM） and methyl formate （MF）.

关键词： heteropolyanion keggin s.ructure methanol dimethyl carbonate carbon dioxide