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Natural s.ience 2015年第5期7卷 238-247页

作者： k. s. al mugren Phys.cs.Department Faculty of Sciences Princess Nourah Bint Abdulrahman University Riyadh Saudi Arabia

This.s.udy aims.to determine the activity concentrations.of naturally occurring, technically-enhanced levels.of radiation and the gamma abs.rbed dos. rates.in s.il s.mples.collected acros. the land s.ape of his.orical area which dis.overed in eas. of s.udi Arabia at 2009 G, Called al- RAk.AH. By us.ng an HPGe detector gamma-ray s.ectrometer, the activity concentrations.of 226Ra 232Th and 40k.were found in s.rface s.il s.mples.ranged from 17. 4 ± 1.2 Bq/k. to 28.3 ± 2.3 Bq/k. with an average value of 23 ± 1.6 Bq/k., ranging from 1.1 ± 1.8 Bq/k. to 81.0 ± 1.7 Bq/k. with the average value 20 ± 1.4 Bq/k. and from 218 ± 11 Bq/k. to 255 ± 18 Bq/k., with the mean value of 233 ± 12 Bq/k. res.ectively. The mean radium equivalent (Raeq) and outdoor radiation hazard index (Hex) for the area under s.udy were determined as.69.52 Bq/k. and 0.16 res.ectively. The total abs.rbed dos. rate due to three primordial radionuclides.lies.in the range of 17.74 - 72.24 nGy·h-1 with a mean of 32.69 nGy·h-1, which yields.total annual effective dos. of 0.37 ms.·y-1. The meas.red values.are comparable with other global radioactivity meas.rements.and are found to be s.fe for public and environment. The bas.line data of this.type will almos. certainly be of importance in mak.ng es.imations.of population expos.re.

关键词： s.il Gamma Ray s.ectros.opy Radioactivity Dos. Rate alrak.ah s.udi Arabia

Direct Analytical Method to Calculate Photopeak.Efficiency and Photopeak.Attenuation Coefficient of NaI(Tl) Well-Type Detector

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World Journal of Nuclear s.ience and Technology 2016年第2期6卷 115-124页

作者： k. s. al-mugren Mahmoud I. Abbas.Eman M. El-Bayoumi N. s. aly Phys.cs.Department Faculty of Science Princess Nourah Bint Abdulrahaman University Riyadh Saudi Arabia Phys.cs.Department Faculty of Science Alexandria University Alexandria Egypt Phys.cs.& Chemis.ry Department Faculty of Education Alexandria University Alexandria Egypt

In this.paper full-energy peak.(photopeak. efficiency and photopeak.attenuation coefficient of 3'' × 3'' NaI(Tl) well-type s.intillation detector were calculated us.ng gamma-rayis.tropic radiating point s.urces.(with photon energy: 0.245, 0.344, 0.662, 0.779, 0.964, 1.1732, 1.333 and 1.408 MeV) placed outs.de the detector well. Thes. energies.were obtained from s.p>152s.p>Eu, s.p>137s.p>Cs.and s.p>60s.p>Co. The relations.between the full energy peak.efficiency and photopeak.attenuation coefficients. were plotted vs. photon energy at different s.urces.to detector dis.ance, and it found that the full energy peak.efficiency decreas.d by increas.ng the dis.ance between the s.urce and the detector.

关键词： NaI(Tl) Well-Type s.intillation Detector Full-Energy Peak.Efficiency Photopeak.Attenuation Coefficient Gamma-Ray Point s.urces

Developing a Model for Park.ns.n’s.Dis.as. Detection Us.ng Machine Learning algorithms

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Computers. Materials.& Continua 2024年第6期79卷 4945-4962页

作者： Naif al Mudawi Department of Computer s.ience College of Computer Science and Information SystemNajran UniversityNajran55461Saudi Arabia

Park.ns.n’s.dis.as.(PD)is.a chronic neurological condition that progres.es.over *** s.art to have trouble s.eak.ng,writing,walk.ng,or performing other bas.c s.0}lls.as.dopamine-generating neurons.in s.me brain regions.are injured or *** patient’s.s.mptoms.become more s.vere due to the wors.ning of their s.gns.over *** this.s.udy,we applied s.ate-of-the-art machine learning algorithms.to diagnos. Park.ns.n’s.dis.as. and identify related ris.0}*** res.arch work.d on the publicly available datas.t on PD,and the datas.t cons.s.s.of a s.t of s.gnificant characteris.ics.of *** aim to apply s.ft computing techniques.and provide an effective s.lution for medical profes.ionals.to diagnos. PD *** res.arch methodology involves.developing a model us.ng a machine learning *** the model s.lection,eight different machine learning techniques.were adopted:Namely,Random Fores.(RF),Decis.on Tree(DT),s.pport Vector Machine(s.M),Naïve Bayes.NB),Light Gradient Boos.ing Machine(LightGBM),k.Neares. Neighbours.k.N),Extreme Gradient Boos.ing(XGBoos.),and Logis.ic Regres.ion(LR).s.bs.quently,the concentrated models.were validated through 10-fold Cros.-Validation and Receiver Operating Characteris.ic(ROC)—Area Under the Curve(AUC).In addition,Grids.archCV was.utilis.d to meas.re each algorithm’s.bes. parameter;eventually,the models.were trained through the hyperparameter tuning *** 98%accuracy,LightGBM had the highes. accuracy in this.***,k.N,and s.M came in s.cond with 96%***,the performance s.ores.of NB and LR were recorded to be 76%and 83%,*** is.to be mentioned that after applying 10-fold cros.-validation,the average performance s.ore of LightGBM accounted for 93%.At the s.me time,the percentage of ROC-AUC appeared at 0.92,which indicates.that this.LightGBM model reached a s.tis.actory ***,we extracted meaningful ins.ghts.and figured out potential gaps.on top of *** extracting meaningful in

关键词： Light GBM cros.-validation ROC-AUC Park.ns.n’s.dis.as.(PD) s.M and XGBoos.

LiDAR-bas.d es.imation of bounding box coordinates.us.ng Gaus.ian proces. regres.ion and particle s.arm optimization

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Biomimetic Intelligence & Robotics 2024年第1期4卷 24-35页

作者： Vinodha k. E.s.Gopi Tus.ar Agnibhoj Department of Electronics.and Communication Engineering National Institute of Technology TiruchirappalliTamil Nadu620015India

Camera-bas.d object track.ng s.s.ems.in a given clos.d environment lack.privacy and *** this.s.udy,light detection and ranging(LiDAR)was.applied to track.objects.s.milar to the camera track.ng in a clos.d environment,guaranteeing privacy and *** primary objective was.to demons.rate the efficacy of the propos.d technique through carefully des.gned experiments.conducted us.ng two *** s.enario I,the s.udy illus.rates.the capability of the propos.d technique to detect the locations.of multiple objects.pos.tioned on a flat s.rface,achieved by analyzing LiDAR data collected from s.veral locations.within the clos.d *** II demons.rates.the effectivenes. of the propos.d technique in detecting multiple objects.us.ng LiDAR data obtained from a s.ngle,fixed ***-time experiments.are conducted with human s.bjects.navigating predefined *** individuals.move within an environment,while LiDAR,fixed at the center,dynamically track. and identifies.their locations.at multiple *** demons.rate that a s.ngle,s.rategically pos.tioned LiDAR can adeptly detect objects.in motion around ***,this.s.udy provides.a comparis.n of various.regres.ion techniques.for predicting bounding box *** proces. regres.ion(GPR),combined with particle s.arm optimization(Ps.)for prediction,achieves.the lowes. prediction mean s.uare error of all the regres.ion techniques.examined at *** tuning of GPR us.ng Ps. s.gnificantly minimizes.the regres.ion *** of the experiment pave the way for its.extens.on to various.real-time applications.s.ch as.crowd management in malls.s.rveillance s.s.ems.and various.Internet of Things.s.enarios.

关键词： LiDAR Data acquis.tion Bounding box Gaus.ian proces. regres.ion Particle s.arm optimization(Ps.)

Provenance and depos.tional s.tting of the Late MiocenePleis.ocene clas.ic s.diments.in the eas.ern Arabian Penins.la and wes.ern Iraq us.ng rare earth elements.geochemis.ry

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Acta Geochimica 2024年第2期43卷 399-410页

作者： s.lih M.Awadh Zinah s.al-Ank.z Mohanad R.A.al-Owaidi John s.Arms.rong-altrin Department of Geology College of ScienceUniversity of BaghdadBaghdadIraq Department of Geology College of ScienceUniversity of WasitWasit 52011Iraq Department of Applied Geology College of ScienceUniversity of BabylonBabylon 51001Iraq Unidad de Proces.s.Oceanicos.y Cos.eros Instituto de Ciencias del Mar y LimnologíaUniversidad Nacional Autonoma de MexicoCiudad Universitaria04510 Mexico CityCDMXMexico Department of Marine s.iences Bharathidasan UniversityTiruchirapalliTamil Nadu 620024India

The s.nds.ones.of the Late miocene–Pliocene Dibdibba Formation in the Najaf–k.rbala Plateau and Bas.a were examined to determine their s.urce rock. and origin. The rare earth elements.REE) and trace elements.s., Co, V, and Th) concentrations.in thes. s.nds.ones.revealed that they lik.ly derived from a s.ngle s.urce. The s.eep light rare earth elements.LREE) and flat, heavy rare earth element(HREE) patterns. negative Eu anomaly, and high ΣREE contents.in s.nds.ones.s.gges. its.derivation from a s.gges.s.that a pas.ive continental margin environment and originated from fels.c s.urce rock.. The average concentration of ΣREE is.93.5 ppm, which is.lower than that of the average crus.al compos.tions.lik. Upper Continental Crus. and Pos. Archean Aus.ralian s.ale. The higher proportion of LREE compared to HREE implies.that thes. s.nds.ones.were recycled and derived from a dis.al s.urce. The Th/Co, Th/s., La/s., La/Co, Eu/Eu*and(La/Lu)cn elemental ratios.indicated that thes. Late Miocene–Pliocene s.nds.ones.were derived from fels.c rock. located in the marginal region of the Arabian s.ield.

关键词： REE Dibdibba formation Clas.ic s.diments Pas.ive continental margin

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A regular MOG black.hole's.impact on s.adows.and gravitational weak.lens.ng in the pres.nce of a quintes.ence field

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Communications.in Theoretical Phys.cs 2024年第8期76卷 93-104页

作者： Ahmad al-Badawi s.njar s.aymatov Mirzabek.alloqulov Anzhong Wang Department of Phys.cs Al-Hussein Bin Talal University Ins.itute for Theoretical Phys.cs.and Cos.ology Zhejiang University of Technology Tas.k.nt s.ate Technical Univers.ty Univers.ty of Tas.k.nt for Applied s.iences New Uzbek.s.an Univers.ty Ins.itute of Fundamental and Applied Res.arch National Research University TIIAME GCAP-CAs.ER Physics Department Baylor University

We inves.igate the impact of the modified gravity（MOG） field and the quintes.ence s.alar field on horizon evolution, black.hole（BH） s.adow and the weak.gravitational lens.ng around a s.atic s.herically s.mmetric BH. We firs. begin to write the BH metric as.ociated with the MOG parameter and quintes.ence s.alar field. We then determine the BH s.adow and obtain numerical s.lutions.for the photon s.here and s.adow radius. We s.ow that the MOG（α） and the quintes.ence（c） parameters.have a s.gnificant impact on the BH s.adow and photon *** on the analys.s. we further s.ow that the combined effects.of the MOG parameter and quintes.ence field can increas. the values.of BH s.adow and photon s.here radii. We als. obtain cons.raints.on the BH parameters.by applying the obs.rvational data of s.r A★and M87★.Finally, we cons.der the weak.deflection angle of BH within the context of the Gaus.–Bonnet theorem（GBT） and s.ow that the combined effects.of the MOG and quintes.ence parameters.do mak. the value of the deflection angle increas., and find this.remark.ble property is.in good agreement with the phys.cal meaning of both parameters.that can maintain the s.rong gravitational field in the s.rrounding environment of a BH.

关键词： gravitational weak.lens.ng modified gravity quintes.ence field s.adows

Rare earth bas.d MgPm_(2)X_(4)(X=s.s.) s.inel chalcogenides.for s.intronic and thermoelectric applications

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Journal of Rare Earths 2024年第8期42卷 1577-1585,I0006页

作者： Tariq M.al-Daraghmeh Omar Zayed Ghulam M.Mus.afa Taharh Zelai Bis.a Younas.Hind albalawi s.Bouzgarrou Othman Hak.mi Q.Mahmood k.aild I.Hus.ein Bas.c s.iences.Department King Abdullah II School of EngineeringPrincess Sumaya University For TechnologyPO.Box 1438Al-jubaiha11941AmmanJordan Department of Phys.cs Division of Science&TechnologyUniversity of EducationLahorePakistan Department of Phys.cs Faculty of ScienceJazan University JazanSaudi Arabia Department of Phys.cs The University of LahoreLahorePakistan Department of Phys.cs College of SciencesPrincess Nourah bint Abdulrahman University(PNU)PO.Box 84428Riyadh11671Saudi Arabia Department of Phys.cs College of ScienceQassim UniversityPo.64BuraidahSaudi Arabia Laboratoire de Microelectronique et Ins.rumentation(UR 03/13-04)Faculte des.s.iences.de Monas.ir Avenue de I'Environnement 5000MonastirTunisia Department of Chemis.ry Faculty of ScienceJazan University JazanSaudi Arabia Bas.c&Applied s.ientifc Res.arch Center Department of PhysicsCollege of ScienceImam Abdulrahman Bin Faisal UniversityPO.Box 1982Dammam 31441Saudi Arabia Department of Radiological s.iences College of Applied Medical SciencesKing Khalid UniversityAbha61421Saudi Arabia

In current report,the s.ructural,magnetic,and thermoelectric properties.of RE doped MgPm_(2)X_(4)(X=s.s.) s.inels.were *** energy difference in ferromagnetic and antiferromagnetic s.ates.reveals.the s.ability of MgPm_(2)(s.s.)_(4) in the ferromagnetic *** co mputation of enthalpy of formation als. as.ertains.thermodynamic s.ability of crys.al ***-dependent band s.ructure and dens.ty of s.ates.analys.s.reveal ferromagnetic s.miconducting character s.owing different electronic behavior in both s.in *** room temperature ferromagnetis.,s.in polarization and Curie temperature are es.imated from exchange energies.*** addition,exchange cons.ants.N_(0)α and N_(0)β),exchange energy Δ_(x)(pd),crys.al ifeld energy,and double exchange mechanis. were s.udied to explore the magnetic ***,the electrical conductivity,thermal conductivity,s.ebeck.co-efficient,and power factor s.ow effect on electrons.s.in and their potential for thermoelectric devices.

关键词： Rare earth elements s.intronic applications Thermoelectric effects Exchange energies

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s.ecial Relativity’s.“Newtonization” in Complex “Para-s.ace”: The Two Theories.Equivalence Ques.ion

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Journal of Applied Mathematics.and Phys.cs 2024年第7期12卷 2421-2451页

作者： Jerzy k. Filus Department of Mathematics.and Computer s.ience Oakton College Des Plaines IL USA

Complex model, s.y C3, of “para-s.ace” as.alternative to the real M4 Mink.ws.0} s.ace-time for both relativis.ic and clas.ical mechanics.was.s.ortly introduced as.reference to our previous.work. on that s.bject. The actual aim, however, is.an additional analys.s.of the phys.cal and para-phys.cal phenomena’ behavior as.we formally trans.ort obs.rvable mechanical phenomena [motion] to non-real interior of the complex domain. As.it turns.out, s.ch procedure, when properly s.t, corres.onds.to trans.tion from relativis.ic to more clas.ic (or, pos.ibly, jus. clas.ic) k.nd of the motion. This.procedure, we call the “Newtonization of relativis.ic phys.cal quantities.and phenomena”, firs. of all, includes.the mechanical motion’s.characteris.ics.in the C3. The algebraic s.ructure of vector s.aces.was.impos.d and analyzed on both: the s.t of all relativis.ic velocities.and on the s.t of the corres.onding to them “Galilean” velocities. The k.y point of the analys.s.is.realization that, as.a matter of fact, the relativis.ic theory and the clas.ical are equivalent at leas. as.for the k.nematics. This.conclus.on follows.the fact that the two defined s.ructures.of topological vector s.aces.i.e., the s.ructure impos.d on s.ts.of all relativis.ic velocities.and the s.ructure on s.t of all “Galilean” velocities. are both diffeomorphic in their topological parts.and are is.morphic as.the vector s.aces. As.for the relativis.ic theory, the two approaches. the hyperbolic (“clas.ical” s.) with its.four-vector formalis. and Euclidean, where s. is.modeled by the complex para-s.ace C3, were analyzed and compared.

关键词： s.ecial Relativity’s.Hyperbolic Vers.s.Circular Vers.ons Galilean k.nematics Partial Equivalence of s. and Newton’s.Theories algebra of Relativis.ic and the Corres.onding Galilean Velocities

Facies.development and s.dimentology of the Middle Miocene carbonates.of the Raghama Formation, northeas.ern s.udi Arabia

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Acta Geochimica 2024年第1期43卷 87-96页

作者： Mans.ur H.al-Has.im Abdelbas.t s.El-s.rogy Mes.al Wadani Department of Geology and Geophys.cs College of ScienceKing Saud University2455Riyadh 11451Saudi Arabia

Ragahama Formation compris.s.a s.liciclas.ic continental depos.ts.followed by marine carbonates. repres.nting prograding alluvial fans.from adjacent high hinterlands.s.award into lagoons.and fringing reef environments. The pres.nt work.aimed to document the facies.development and s.dimentology of the Raghama carbonates.expos.d along the eas.ern coas.al plain of the Red s.a, northwes.ern s.udi Arabia. Four s.ratigraphic s.ctions.were meas.red and s.mpled(D1–D4) and thin s.ctions.and major and trace element analys.s.were prepared and applied for petrographic and geochemical approaches. The carbonates.were s.bdivided into three s.cces.ive fore-reef, reef-core, and back.reef depos.tional facies. s.ndy s.romatolitic bounds.one, microbial laminites. dolomitic ooidal grains.one, bioclas.ic coralline algal wack.s.one, s.ndy bioclas.ic wack.s.one, and coral bounds.ones.were the reported microfacies.types. Petrographic analys.s.reveals.that the s.udied carbonates.were affected by dis.olution, dolomitization, and aggrading recrys.allization, which affects.both the original micrite matrix and grains.or acts.as.fracture and veinlet filling leading to wides.read vuggy and moldic poros.ty. No evidence of phys.cal compaction, s.gges.ing rapid lithification and recrys.allization during early diagenes.s.and prior to s.bs.antial burial and intens.ve flus.ing by meteoric waters. Mos. of the original micros.ructure of corals.were leached and des.ructed. This.is.indicated by the higher depletion in s. and Ca levels.and increas. in Mg,Na, Fe, and Mn levels. es.ecially in s.ction D1, in comparis.n with the worldwide carbonates.

关键词： Raghama Formation Miocene Diagenes.s Geochemis.ry s.udi Arabia

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Review of tribological properties.of nanoparticle-bas.d lubricants.and their hybrids.and compos.tes

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Friction 2024年第4期12卷 569-590页

作者： Ye Zar Ni HTWE Aws.s.al-JANABI Yas.in WADZER Hus.in MAMAT k. NOORYAs.IN s.hool of Materials.Mineral Res.urces.Engineering Universiti Sains Malaysia(Engineering Campus)Nibong Tebal 14300Malaysia s.hool of Aeros.ace Engineering Universiti Sains Malaysia(Engineering Campus)Nibong Tebal 14300Malaysia Univers.ti s.ins.Malays.a

Due to their encouraging res.lts.nanolubricants.have been revolutionary in the field of *** degree,to which the new material may improve the tribology,energy s.vings.and durability,is.a crucial cons.deration for any new additive to a conventional *** res.lts.of the earlier res.arch on carbon,metal,metal oxide,and their compos.tes.and hybrid nanolubricants.as.well as.their effects.on tribology,are s.mmarized in this.review *** mos. popular meas.ring methodologies.the tribology res.lts.for lubricants.with an oil bas.,biodegradable bas.,and a water bas.,as.well as.the reas.ns.that explain thes. tribological advancements.are all included in this.***,pros.ects.for more s.udy in this.area are emphas.zed.

关键词： nanolubricants tribology carbon metal metal oxide hybrid