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Estimation of radiation hazard indices from natural radioactivity of some rocks

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nuclear Science and Techniques 2006年第2期17卷 118-122页

作者： A.ABBADY n.k.ahmed A.M.EL-ARABI R.MICHEL A.H.EL-kAMEL A.G.E.ABBADY Physics Department Faculty of Science Qena South Valley University Egypt Institute of the Radiation Protection and Radioecology Hannover University Germany Physics Department Faculty of Science Assiut University Egypt

Different samples of igneous and metamorphic rocks from Egypt and Germany have been considered to measure γ-ray activity concentrations due to naturally occurring, potentially hazardous radonuclides 226Ra, 232Th and 40k. The radiation hazard parameters including radiation equivalent activity, gamma-absorbed dose rate, and exter- nal and internal hazard indices have been estimated. The gamma-absorbed dose rates in air of rocks in Egypt range from 4.2 to 128.5 nGy·h-1 with a mean value of 55.3 nGy·h-1. For igneous and metamorphic rocks from Germany, the values of absorbed dose rates fluctuate from 5.1 to 148.6 nGy·h-1, with a mean value of 60.9 nGy·h-1. Generally, it is found that the radiation hazard indices in common igneous rocks are distinctly higher in acidic than in ultrabasic rocks. The results are discussed and compared with the corresponding published data.

关键词：自然放射性岩石变质岩环境放射学

EDSUCh:A robust ensemble data summarization method for effective medical diagnosis

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Digital Communications and networks 2024年第1期10卷 182-189页

作者： Mohiuddin ahmed A.n.M.Bazlur Rashid School of Science Edith Cowan UniversityPerthAustralia

Identifying rare patterns for medical diagnosis is a challenging task due to heterogeneity and the volume of *** summarization can create a concise version of the original data that can be used for effective *** this paper,we propose an ensemble summarization method that combines clustering and sampling to create a summary of the original data to ensure the inclusion of rare *** the best of our knowledge,there has been no such technique available to augment the performance of anomaly detection techniques and simultaneously increase the efficiency of medical *** performance of popular anomaly detection algorithms increases significantly in terms of accuracy and computational complexity when the summaries are ***,the medical diagnosis becomes more effective,and our experimental results reflect that the combination of the proposed summarization scheme and all underlying algorithms used in this paper outperforms the most popular anomaly detection techniques.

关键词： Data summarization Ensemble Medical diagnosis Sampling

Effectiveness of external prestressing in enhancing the non-ductile hanger failure mechanism in reinforced concrete inverted T-beams

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1050-1065页

作者： ahmed M.ATTA Reda n.BEHIRY Mohammed I.HARAZ Structural Engineering Department Faculty of EngineeringTanta UniversityTanta 33511Egypt nile Higher Institute for Engineering and Technology Mansoura 11001Egypt

Recently,inverted T-beams have been used in reinforced concrete(RC)bridges to support transverse precast *** T-beams,contrary to practice with conventional beams,are loaded on the flanges upper *** loading configuration causes hanger failure due to the generation of vertical tensile stresses near the bottom of the *** key purpose of this study is to investigate the efficiency of vertical external prestressing stainless-steel bars in mitigating non-ductile hanger failure in reinforced concrete inverted *** experimental study on six inverted-T beams,including two un-strengthened specimens,was carried *** study showed that the value of the prestressing level had a considerable impact on the performance of hanger mechanism in relation to crack pattern,ultimate loads,cracking behavior,load-deflection,strains,and *** experimental results indicated that the suggested method for strengthening inverted T-beams had efficacy in reducing the seriousness of the non-ductile hanger failure and resulted in a strength increase of up to 53% when compared to that of the un-strengthened ***,two analytical models for estimating the hanger capacity and the average crack width of the strengthened RC inverted T-beams were *** models that were proposed exhibited a high degree of agreement with the experimental results.

关键词： RC bridges inverted T-beams strengthening hanger failure external prestressing

The Lambert-G Family:Properties,Inference,and Applications

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 513-536页

作者： Jamal n.Al Abbasi ahmed Z.Afify Badr Alnssyan Mustafa S.Shama Accounting Department Ashur UniversityBaghdad10011Iraq Department of Statistics Mathematics and InsuranceBenha UniversityBenha13511Egypt Department of Management Information Systems and Production Management College of Business and EconomicsQassim UniversityBuraydah51452Saudi Arabia Department of Basic Sciences Common First Year(CFY)King Saud UniversityRiyadh11362Saudi Arabia Department of Mathematics and Statistics Osim Higher Institute of Administrative ScienceOsim12961Egypt

This study proposes a new flexible family of distributions called the Lambert-G *** Lambert family is very flexible and exhibits desirable *** three-parameter special sub-models provide all significantmonotonic and non-monotonic failure rates.A special sub-model of the Lambert family called the Lambert-Lomax(LL)distribution is *** expressions for the LL statistical properties are *** of the LL distribution are addressed mathematically based on its hazard *** estimation of the LL parameters is discussed using six estimation *** performance of this estimation method is explored through simulation *** usefulness and flexibility of the LL distribution are demonstrated empirically using two real-life data *** LL model better fits the exponentiated Lomax,inverse power Lomax,Lomax-Rayleigh,power Lomax,and Lomax distributions.

关键词： Lambert function Lomax distribution maximum likelihood hazard function statistical model simulation

Application of Synthetic Iron Oxyhydroxide with Influencing Factors for Removal of As(Ⅴ) and As(Ⅲ) from Groundwater

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Journal of Earth Science 2024年第3期35卷 998-1009页

作者： Shakeel ahmed Talpur Muhammad Yousuf Jat Baloch Chunli Su Javed Iqbal Aziz ahmed Hafeez ahmed Talpur School of Environmental Studies China University of GeosciencesWuhan 430078China DiSPUTer Department of PsychologicalHealth and Territory SciencesUniversity“G.d′Annunzio”Chieti-Pescara66100 ChietiItaly College of new Energy and Environment Jilin UniversityChangchun 130021China School of Plant Environment and Soil SciencesLouisiana State University Agricultural CentreBaton Rouge LA 70803USA Department od Engineering and Geology University“G.d′Annunzio”Chieti-Pescara66100 ChietiItaly

Synthesized iron oxyhydroxide was applied for the adsorptive removal of As(V)and As(III)from the aquas ***,this investigation highlighted the synergistic effect of calcium carbonate in conjunction with iron oxyhydroxide,resulting in enhanced removal *** experiment was conducted under various conditions:concentration,dosage,pH,agitation,and *** characterizations such as Brunauer Emmett Teller,X-ray diffraction,scanning electron microscopy,and Fourier transform infrared spectroscopy were implied to understand adsorption *** Langmuir model revealed optimal concentrations for As(V)=500μg/L at pH-5 and As(III)=200μg/L at pH-7,resulting in 95%and 93%adsorption efficiencies,*** adsorption capacities“qm”were found to be 1266.943μg/g for As(V)and 1080.241μg/g for As(III).Freundlich model demonstrated favorable adsorption by indicating“n>1”such as As(V)=2.542 and As(III)=2.707;similarly,the speciation factor“RLnd As(III)=0.5,*** kinetic study presented a pseudo-second-order model as best fitted,indicating throughout chemisorption processes for removing As(V)and As(III).Furthermore,incorporating calcium carbonate presented a significant leap in the removal efficiency,indicating As(V)from 95%to 98%and As(III)from 93%to 96%,*** findings offer profound motivation for developing effective and sustainable solutions to tackle arsenic contamination,underscoring the exceptional promise of iron oxyhydroxide in conjunction with calcium carbonate to achieve maximum removal efficiency.

关键词： adsorption arsenic As(V) As(III) iron oxyhydroxide isotherms kinetics groundwater.

The interplay mechanism between IDH mutation, MGMT-promoter methylation, and PRMT5 activity in the progression of grade 4 astrocytoma: unraveling the complex triad theory

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Oncology Research 2024年第6期32卷 1037-1045页

作者： MAHER kURDI ALAA ALkHOTAnI ABDULRAHMAn SABBAGH EYAD FAIZO ahmed I.LARY ahmed k.BAMAGA MAJID ALMAnSOURI BADR HAFIZ THAMER ALSHARIF SALEH BAEESA Department of Pathology Faculty of MedicineKing Abdulaziz UniversityRabighSaudi Arabia Department of Pathology College of MedicineUmm Al-Qura UniversityMakkahSaudi Arabia Department of Surgery Faculty of MedicineKing Abdulaziz UniversityJeddahSaudi Arabia Department of Surgery Faculty of MedicineUniversity of TabukTabukSaudi Arabia Section of neurosurgery Department of SurgeryKing Abdulaziz Medical CityJeddahSaudi Arabia Department of Pediatrics Faculty of MedicineKing Abdulaziz UniversityJeddahSaudi Arabia Department of Clinical Biochemistry Faculty of MedicineKing Abdulaziz UniversityJeddahSaudi Arabia Department of neurosciences King Faisal Specialist Hospital and Research CenterJeddahSaudi Arabia Department of Surgery King Abdulaziz Specialist HospitalTaifSaudi Arabia

Background:The dysregulation of Isocitrate dehydrogenase(IDH)and the subsequent production of 2-Hydroxyglutrate(2HG)may alter the expression of epigenetic proteins in Grade 4 *** interplay mechanism between IDH,O-6-methylguanine-DnA methyltransferase(MGMT)-promoter methylation,and protein methyltransferase proteins-5(PRMT5)activity,with tumor progression has never been ***:A retrospective cohort of 34 patients with G4 astrocytoma is classified into IDH-mutant and IDH-wildtype *** groups were tested for MGMT-promoter methylation and PRMT5 through methylation-specific and gene expression PCR ***-cohort statistical significance was ***:Both IDH-mutant WHO grade 4 astrocytomas(n=22,64.7%)and IDH-wildtype glioblastomas(n=12,35.3%)had upregulated PRMT5 gene expression except in one *** of the 22 IDH-mutant tumors,10(45.5%)tumors showed MGMT-promoter methylation and 12(54.5%)tumors had unmethylated *** IDH-wildtype tumors had unmethylated *** was a statistically significant relationship between MGMT-promoter methylation and IDH in G4 astrocytoma(p-value=0.006).Statistically significant differences in progression-free survival(PFS)were also observed among all G4 astrocytomas that expressed PRMT5 and received either temozolomide(TMZ)or TMZ plus other chemotherapies,regardless of their IDH or MGMT-methylation status(p-value=0.0014).Specifically,IDH-mutant tumors that had upregulated PRMT5 activity and MGMT-promoter methylation,who received only TMZ,have exhibited longer ***:The relationship between PRMT5,MGMT-promoter,and IDH is not ***,accumulation of D2-hydroxyglutarate(2-HG),which partially activates 2-OG-dependent deoxygenase,may not affect their *** IDH-wildtype glioblastomas,the 2HG-2OG pathway is typically inactive,leading to PRMT5 *** alone,compared to TMZ-plus,can increase PFS in upregulated PRMT5 ***,using a PRMT5 inhibitor in G4

关键词： Grade 4 astrocytoma Glioblastoma Isocitrate dehydrogenase(IDH) O-6-methylguanine-DnA methyltransferase(MGMT) Protein methyltransferase proteins-5(PRMT5) Progression-free survival(PFS)

Fuel cell stack design and modelling with a double-stage boost converter coupled to a single-phase inverter

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Clean Energy 2024年第1期8卷 188-196页

作者： Basem E.Elnagi ahmed M.Ismaiel Hany S.E.Mansour M.n.Abd-Alwahab Electrical Engineering Department Faculty of EngineeringSuez Canal UniversityIsmailia 41522Egypt

A comprehensive proton-exchange membrane fuel cell stack model was developed and integrated with a two-stage DC/DC boost *** was directly coupled to a single-phase(two levels-four pulses)inverter without a *** pulse-width modu-lation signal was used to independently regulate every converter *** converter was modelled using a MATLAB®/Simulink®environment and an appropriate voltage control *** analysis features of the suggested circuit were created and,through established experiments,the simulation results were verified.A single-phase(two levels-four pulses)inverter control circuit was tested and it produced a pure sinusoidal waveform with voltage *** matches the voltage of the network in terms of amplitude and frequency.A sinusoidal pulse-width modulation approach was performed using a single-phase(two levels-four pulses)pulse-width modulation *** results demonstrated an enhancement in the standard of the output wave and tuned the dead time with a reduction of 63μs compared with 180μs in conventional techniques.

关键词： PEM fuel cell pulse-width modulation single-phase inverter and double-stage DC/DC boost converter

Tilted global solar irradiance in Bahrain:an experimental study

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Clean Energy 2024年第2期8卷 27-34页

作者： n.Vasilikos C.Georgantopoulou H.Alajaimi S.H.Almajed M.ahmed D.Mathioulakis School of Mechanical Engineering Bahrain PolytechnicIsa TownPO Box 33349Kingdom of Bahrain School of Mechanical Engineering National Technical University of AthensHeroon Polytechniou 7 StZografos 15773AthensGreece

In the present work,tilted global solar irradiance data are presented and analysed,measured for a period of 1 year on the campus of Bahrain Polytechnic,kingdom of Bahrain,from both a fixed photovoltaic panel and a moving one via a two-axis solar *** fixed panel faces south with an angle of 26°with respect to the horizontal,coinciding with the local geographical *** second panel is moved by two motors,controlled by a global positioning system and suitable software so that the Sun’s rays are perpendicular to the panel surface.A pyranometer is installed on each panel,recording the tilted global solar irradiance,stored by using a data *** analysis of the data obtained shows a 33%solar energy gain on an annual basis for the moving panel(2780 versus 2088 kWh/m^(2) on the fixed panel).More importantly,in June,when the energy demand in Bahrain is elevated due to the increased residential cooling loads,the solar energy received by the moving panel is 54.7%higher compared with that of the fixed *** a percentage basis,the increase in solar energy from the moving panel is profound in the early morning and late evening ***,the reduction in the solar energy received by the fixed panel from May to June does not appear in the moving panel because of the adjustable orientation of the *** the year,the mean daily solar power varies between 0.37 and 0.56 kW/m^(2) for the fixed panel,and 0.45 and 0.70 kW/m^(2) for the moving *** winter,solar energy fluctuations are elevated due to erratic weather conditions that present a peak standard deviation of 28%of the corresponding *** data presented are useful for potential solar investments in Gulf countries.

关键词： tilted solar irradiance renewable energy solar tracking photovoltaic Gulf Cooperation Council Countries

Utilizing n-hydroxy-9-octadecenamide as a collector in flotation separation of bastnaesite and fluorite

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Journal of Rare Earths 2024年第8期42卷 1620-1628,I0008页

作者： Zhihao Guo Sultan ahmed khoso Mengjie Tian Wei Sun School of Minerals Processing and Bioengineering Central South UniversityChangsha410083China State key Laboratory of Mineral Processing Beijing102600China Hubei key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources Wuhan430081China key Laboratoryof Hunan Province for Cleanand Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha410083China Department of Mining Engineering Mehran University of Engineering&TechnologyJamshoro76062Pakistan

Bastnaesite((Ce,La,Pr,nd)CO_(3)F) is a significant light rare earth mineral found in nature,known for its fine-grained *** is commonly employed for the recovery of fine-grained bastnaesite *** serve as an essential flotation reagent that enhance the surface hydrophobicity of target minerals.A novel collector,n-hydroxy-9-octadecenamide(n-OH-9-ODA),was synthesised in this study.n-OH-9-ODA exhibits superior selectivity compared to the traditional collector oleic acid in the flotation separation of bastnaesite and *** experimental and co mputational results indicate that n-OH-9-ODA exhibits superior selectivity due to its higher adsorption affinity for bastnaesite surface compared to fluorite *** zeta potential and the binding energies of the Ce 3d peaks in the X-ray photoelectron spectrum(XPS) of bastnaesite surface exhibit significant ***,fluorite surface demonstrates minimal alterations in its zeta potential and the binding energies of the Ca 2p peaks in its XPS after its interaction with n-OH-9-ODA.

关键词： Bastnaesite Collector Hydroxamic acids n-hydroxy-9-octadecenamide Oleic acid Rare earths