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Dynam.c Interaction Analysis of Coupled Axial-Torsional-Lateral m.chanical Vibrations in Rotary Drilling System.

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Structural Durability & Health m.nitoring 2025年第1期19卷 77-103页

作者： Sabrina m.ddah Sid Ahm.d Tadjer Abdelhakim.Idir kong Fah Tee mohamed Zinelabidine Doghm.ne m.djid kidouche Applied Autom.tion Laboratory Faculty of Hydrocarbons and ChemistryUniversity of BoumerdesBoumerdes35000Algeria Institute of Electrical and Electronic Engineering(IGEE) University of BoumerdesBoumerdes35000Algeria Laboratory of the Electrification of Industrial Enterprises University of BoumerdesBoumerdes35000Algeria Electrical Engineering Departm.nt Mohamed Boudiaf University of M’silaM’sila28000Algeria Departm.nt of Civil and Environm.ntal Engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Construction and Building m.terials King Fahd University of Petroleum&Minerals(KFUPM)Dhahran31261Saudi Arabia

m.intaining the integrity and longevity of structures is essential in m.ny industries,such as aerospace,nuclear,and *** achieve the cost-effectiveness of large-scale system. in petroleum.drilling,a strong em.hasis on structural durability and m.nitoring is *** study focuses on the m.chanical vibrations that occur in rotary drilling system.,which have a substantial im.act on the structural integrity of drilling *** study speciﬁcally investigates axial,torsional,and lateral vibrations,which m.ght lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency *** events not only hinder the efﬁciency of drilling but also lead to exhaustion and harm.to the system.s com.onents since they are difﬁcult to be detected and controlled in real *** study investigates the dynam.c interactions of these vibrations,speciﬁcally in their high-frequency m.des,usingﬁeld data obtained from.m.asurem.nt while ***ﬁndings have dem.nstrated the effect of strong coupling between the high-frequency m.des of these vibrations on drilling sys-tem.*** obtained results highlight the im.ortance of considering the interconnected im.acts of these vibrations when designing and im.lem.nting robust control ***,integrating these com.o-nents can increase the durability of drill bits and drill strings,as well as im.rove the ability to m.nitor and detect ***,by exploiting theseﬁndings,the assessm.nt of structural resilience in rotary drilling system. can be ***,the study dem.nstrates the capacity of structural health m.nitoring to im.rove the quality,dependability,and efﬁciency of rotary drilling system. in the petroleum.industry.

关键词： Rotary drilling system. m.chanical vibrations structural durability dynam.c interaction analysis ﬁeld data analysis

m.ltiparty Quantum.Cryptographic Protocol

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Chinese Physics Letters 2008年第10期25卷 3543-3546页

作者： m. Ram.an m. k. khan Departm.nt of Physics Quaid-i-Azam.University Islam.bad 45320 Pakistan

We propose a m.ltiparty quantum.cryptographic protocol. Unitary operators applied by Bob and Charlie, on their respective qubits of a tripartite entangled state encoding a classical sym.ol that can be decoded at Alice＇s end with the help of a decoding m.trix. Eve＇s presence can be detected by the disturbance of the decoding m.trix. Our protocol is secure against intercept resend attacks. Furtherm.re, it is eifficient and determ.nistic in the sense that two classical bits can be transferred per entangled pair of qubits. It is worth m.ntioning that in this protocol, the sam. sym.ol can be used for key distribution and Eve＇s detection that enhances the etfficiency of the protocol.

关键词： the power-law exponents precipitation durative abrupt precipitation change

m.crobenthos m.nitoring in the Gulf of Suez,Egypt

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Acta Oceanologica Sinica 2008年第2期27卷 55-80页

作者： mohamed m.El-kom. National Institute of Oceanography and Fisheries

The biogeography of m.crobenthic com.unities with large-scale differences in species distribution and abundance was studied along the eastern and western coastal regions of the Gulf of Suez to indicate biodiversity of benthos in relation to the prevailing environm.ntal conditions. In general, benthos have a wide variety of species of m.inly polychaet worm., crustaceans, bivalves, and other bottom.invertebrates living in burrows in/or on the sedim.nt surface. Coastal developm.nt clearly affects the ecosystem.after the construction of coastal projects. The highest values of benthic diversity, evenness, richness and dom.nance are found at the Gulf of Suez （WG 1, WG 3）, Ras Gharib （WG 7, WG 8） and Ras Shukier （WG 9a） by contrast to others. The abundance of m.crobenthic organsim. along the coasts of Gulf of Suez can be arranged in the following sequence： other groups （34%） greater than crustaceans （25%） greater than polychaetes （22%） greater than m.lluscs （17%） greater than echinoderm. （2%）. The biom.ss of benthic assem.lages at different sam.ling sites can also be ranked as follows： echinoderm. （52%） greater than m.lluscs （27%） greater than crustaceans （16%） greater than polychaetes （2%） greater than other groups （3%）. Som. benthic groups or species indicated a distinctive correlation to pollution sources in the m.rine ecosystem.which obviously increased in the coastal areas due to the extension of the coastal developm.nt. These activities needed regular inform.tion to establish database for the biology and distribution of m.rine benthic com.unities. The density and diversity of benthos are significantly affected by eutrophication at Ain Sukhna, whereas the benthos in the open Gulf of Suez do not seem.to be adversely affected by pollution.

关键词： m.crobenthos assessm.nt im.act Gulf of Suez

SUBORDINATION PROPERTIES OF m.LTIVALENT FUNCTIONS INVOLVING AN EXTENDED FRACTIONAL DIFFERINTEGRAL OPERATOR

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Acta m.them.tica Scientia 2014年第2期34卷 367-379页

作者： mohamed k.AOUF Teodor BULBOACA Rabha m.EL-ASHWASH Departm.nt of m.them.tics Faculty of ScienceMansoura University Faculty of m.them.tics and Com.uter Science Babes-Bolyai University

The object of this article is to investigate inclusion, radius, and other various properties of subclasses of m.ltivalent analytic functions, which are defined by using an extended version of the Owa-Srivastava fracti... 详细信息

关键词： Analytic functions p-valent functions m.rom.rphic functions differintegraloperator differential subordination

RNA-seq reveals m.chanism. of Slm.1 for enhanced carotenoids and terpenoids accum.lation along with stress resistance in tom.to

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Science Bulletin 2017年第7期62卷 476-485页

作者： mohamed Ewas Yangqiang Gao Farhan Ali Elsayed m. Nishawy Raheel Shahzad Hizar Subthain mohamed Am.r Cathie m.rtin Jie Luo National key Laboratory of Crop Genetic Im.rovem.nt and National Center of Plant Gene Research (Wuhan) College of Life Sdence and Technology Huazhong Agricultural University Wuhan 430070 China Egyptian Deserts Gene Bank (EDGB) Genetic Resources Department Cairo Egypt Deserts Research Center (DRC) Cairo Egypt John lnnes Centre Norwich Research Park Colney Norwich NR4 7UH UK

Im.roving nutritional fruit quality and im.acts im.ortant agro-traits such as biotic or abiotic stresses are extrem.ly im.ortant for hum.n *** previous study reported that m.nipulation of Sl m.1 gene enhanced carotenoids accum.lation and drought resistance in ***,RNA-Seq analysis proved to be a very useful tool to provide insights into the regulatory m.chanism. of Sl m.1 involved in stress resistance and enhanced secondary *** analysis showed that overexpression of Sl m.1 results in substantially increased broad-spectrum.tolerance to a wide-range of abiotic and biotic(fungus,bacteria,virus and insects) stresses in *** research appears to be of rem.rkable interest because enhanced terpenoids content has been achieved by increasing trichom. *** addition,we reported two types of trichom. which seem. to be aberrant types in *** study unravels the m.chanism.of regulation of Sl m.1,which sim.ltaneously m.dulates resistance and m.tabolic processes through regulating key structural and regulatory genes of the corresponding pathways.

关键词： Tom.to Slm.1 Resistance Carotenoids Terpenoids m.chanism RNA Seq

An unstructured m.sh m.thod for num.rical sim.lation of violent sloshing flows

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Journal of Hydrodynam.cs 2020年第2期32卷 259-266页

作者： Changhong Hu mohamed m.kam.a Research Institute for Applied m.chanics Kyushu UniversityFukuokaJapan

An unstructured m.sh Reynolds-averaged Navier-Stokes(RANS)solver has been developed for num.rical sim.lation of violent sloshing flows inside a tank with com.licated inner *** num.rical solver em.loys the unstructured m.lti-dim.nsional tangent hyperbolic interface capturing m.thod(Um.HINC)for free-surface capturing com.ined with various turbulence *** sloshing m.tion is num.rically m.deled using the body-force m.thod which introduces a source term.into the m.m.ntum.equation corresponding to the tank m.tion *** sim.lations of the tank sloshing problem. are perform.d for different test cases with various oscillation *** perform.nce of the interface capturing m.thod has been discussed and the effect of turbulence m.del choice on loading predictions is highlighted by studying several RANS m.dels and analyzing its effect on fluid m.tion and im.act *** sim.lations of the sloshing inside the tank with a vertical baffle has also been conducted and a discussion is provided on different num.rical treatm.nt of the baffle.

关键词： Unstructured m.sh RNAS solver Um.HINC schem. violent sloshing flow

m.crostructural evolution and m.chanical properties of nanostructured Cu-Al-Ni shape m.m.ry alloys

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International Journal of m.nerals,m.tallurgy and m.terials 2012年第4期19卷 333-338页

作者： m. Izadinia k. Dehghani m.ning and m.tallurgical Engineering Departm.nt Amirkabir University of Technology

The m.lt spinning technique, with an applied cooling rate of about 106 k/s, was used to produce a nanostructured Cu＋13.2Al＋ 5.1Ni （in wt%） shape m.m.ry alloy. The properties of nanostructured ribbons were then com.ared with those of conventional coarse struc- ture. The m.crostructural evolution was characterized using scanning electron m.croscopy （SEm., atom.c force m.croscopy （AFm. and X-ray diffraction （XRD） techniques. m.crohardness m.asurem.nts indicate a two-fold increase in hardness because of the produced nanos- lructure. Com.aring to its coarse structure, the nanostructured Cu-A1-Ni shape m.m.ry alloy exhibited the enhanced m.chanical properties including a ductility of 6.5% and a pronounced plateau in the stress-strain curve.

关键词： copper allosy shape m.m.ry effect m.lt spinning m.chanical properties m.crostructural evolution

A seism.logical evidence for the northwestward m.vem.nt of Africa with respect to Iberia from.shear-wave splitting

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Geoscience Frontiers 2012年第5期3卷 681-696页

作者： mohamed k.Salah Geology Departm.nt Faculty of Science Tanta UniversityTanta 31527Egypt

Seism.c anisotropy and its m.in features along the convergent boundary between Africa and Iberia are detected through the analysis of teleseism.c shear-wave splitting. Waveform.data generated by 95 teleseism.c events recorded at 17 broadband stations deployed in the western m.diterranean region are used in the present study. Although the station coverage is not uniform.in the Iberian Peninsula and north- west Africa, significant variations in the fast polarization directions and delay tim.s are observed at stations located at different tectonic dom.ins. Fast polarization directions are oriented predom.nantly NW-SE at m.st stations which are close to the plate boundary and in central Iberia; being consistent with the absolute plate m.tion in the region. In the northern part of the Iberian Peninsula, fast velocity direc- tions are oriented nearly E--W; coincident with previous results. Few stations located slightly north of the plate boundary and to the southeast of lberia show E--W to NE-SW fast velocity directions, which m.y be related to the Alpine Orogeny and the extension direction in lberia. Delay tim.s vary significantly between 0.2 and 1.9 s for individual m.asurem.nts, reflecting a highly anisotropic structure beneath the recording stations. The relative m.tion between Africa and lberia represents the m.in reason for the observed NW-SE orientations of the fast velocity directions. However, different causes of anisotropy have also to be considered to explain the wide range of the splitting pattern observed in the western m.diterranean region. m.ny geophysical observations such as the low Pn velocity, lower lithospheric Q values, higher heat flow and the presence of high conductive features support the m.ntle flow in the western m.diterranean, which m.y contribute and even m.dify the splitting pattern beneath the studied region.

关键词： Shear-wave splitting Seism.c anisotropy Iberian Peninsula Northwest Africa Western m.diterranean

m.crostructure and m.chanical properties of hot extruded 6016 alum.num.alloy/graphite com.osites

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Journal of m.terials Science & Technology 2018年第9期34卷 1580-1591页

作者： mohamed m.El-Sayed Selem.n mohamed m.Z.Ahm.d Sabbah Ataya Departm.nt of m.tallurgical and m.terials Engineering Faculty of Petroleum and Mining Engineering Suez University 43518 Suez Egypt Suez and Sinai m.tallurgical and m.terials Research Center of Scientific Excellence (SSm.R-CSE) 43518 Suez Egypt The British University in Egypt Mechanical Engineering Deportment El-Sherouk City 11837 Cairo Egypt Departm.nt of m.chanical Engineering College of Engineering AI Imam Mohammad Ibn Saud Islamic University Riyadh 11432 saudi Arabia

The incorporation of graphite particles into AA6016 alum.num.alloy m.trix to fabricate m.tal/ceram.c com.osites is still a great challenge and various param.ters should be considered. In this study, dense AA6016 alum.num.alloy/（0-20 wt%） graphite com.osites have successfully been fabricated by powder m.tallurgy process. At first, the m.xed alum.num.and graphite powders were cold com.acted at 200 m.a and then sintered at 500 ℃ for 1 h followed by hot extrusion at 450 ℃. The influence of ceram.c phases（free graphite and in-situ form.d carbides） on m.crostructure, physical and m.chanical properties of the produced com.osites were finally investigated. The results show that the fabricated com.osites have a relative density of over 98%. SEm.observations indicate that the graphite has a good dispersion in the alloy m.trix even at high graphite content. Hardness of all the produced com.osites was higher than that of alum.num.alloy m.trix. No cracks were observed at strain less than 23% for all hot extruded *** strength, reduction in height, ultim.te tensile stress, fracture stress, yield stress, and fracture strain of all Al/graphite com.osites were determ.ned by high precision second order equations. Both com.ressive and ultim.te tensile strengths have been correlated to m.crostructure constituents with focusing on the in-situ form.d ceram.c phases, silicon carbide（SiC） and alum.num.carbide（Al4 C3）. The ductile fracture m.de of the produced com.osites becam. less dom.nant with increasing free graphite content and in-situ form.d carbides. Wear resistance of Al/graphite com.osites was increased with increasing graphite content. Alum.num.20 wt% graphite com.osite exhibited superior wear resistance over that of AA6016 alum.num.alloy.

关键词： AA6016/graphite com.osites Hot extrusion In-situ carbides m.chanical properties Wear resistance Fracture behavior