检索结果-南通市图书馆

Validation of <sup>226</sup>Ra and <sup>228</sup>Ra m.asurem.nts in Water Sam.les Using Gam.a Spectrom.tric Analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Water Resource and Protection 2013年第8期5卷 53-57页

作者： Hanan m. Diab waleed m. abdellah Nuclear and Radiological Regulatory Authority Cairo Egypt

Radium.isotopes can be analyzed by different analytical m.thods based on gam.a spectrom.tric m.asurem.nts or alpha spectrom.try. An im.roved m.thod was developed to determ.ne radium.isotopes from.water using gam.a spectrom.try after radiochem.cal separation. The Radium.was selectively extracted from.acidified sam.les using co-precipitation procedure with iron hydroxide and followed by precipitation of radium.as radium.sulphate Ba(Ra)SO4. The precipitate Ba(Ra)SO4 was filtered through the m.llipore filter paper, dried and weighed to calculate chem.cal yield. 226Ra and 228Ra activities were m.asured using low-background gam.a spectrom.try in water sam.les. Radium.was pre-concentrated from.environm.ntal sam.les by co-precipitation with BaSO4. The am.unts of 226Ra and 228Ra on the sam.le were obtained by gam.a-ray spectrom.try for the 351 keVγ-ray from.214Pb and for the 911 keV γ-ray from.228Ac, both in radioactive equilibrium.with precursors, respectively. The accuracy, selectivity, traceability, applicability and m.nim.m.Detectable Activity (m.A) of the technique were discussed. Also, the effect of physical and chem.cal characteristics of the water sam.les such as TDS, pH, soluble species, sulphate and bicarbonate that effect on the radium.determ.nation were taking into consideration. The m.thod has been validated with a certified reference m.terial supplied by the International Atom.c Energy Agency and reliable results were obtained. The radiochem.cal yields for radium.were 70% - 90% and recovery was 97% and 80% for 226Ra and 228Ra, respectively.

关键词： Radium Isotopes Gam.a-Ray Spectrom.try Water Analysis

Global output of research on epiderm.l parasitic skin diseases from.1967 to 2017

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Infectious Diseases of Poverty 2018年第1期7卷 730-739页

作者： waleed m.Sweileh Departm.nt of Physiology Pharmacology/ToxicologyDivision of Biomedical SciencesCollege of Medicine and Health SciencesAn-Najah National UniversityNablusPalestine

Background:Epiderm.l parasitic skin diseases(EPSD)occur in m.st countries and cause a considerable health and econom.c burden,particularly in the tropics and *** aim.of this study was to assess and analyse peerreviewed literature on EPSD in *** results of this study serve as an indicator of the extent the scientific com.unity,health authorities,and international health agencies interact with EPSD as a health problem.that is com.only associated with poverty and poor ***:A bibliom.tric analysis m.thodology was *** Scopus database was used to retrieve docum.nts about EPSD for the study period(1967-2017).The study focused on scabies,tungiasis,pediculosis,hookworm.elated cutaneous larva m.grans(HrCLm.,m.iasis,and cutaneous *** that specifically and explicitly discuss EPSD in anim.ls,aquatic organism.,and birds were ***:In total,4186 docum.nts were retrieved.A fluctuated growth of publications on EPSD in the past five decades was *** retrieved docum.nts received 43301 citations,an average of 10.3 citations per article and an h-index of *** keywords“scabies”and was the m.st com.only encountered keyword followed by the keywords“head lice”and“pediculosis”.The m.st active journal involved in publishing articles on EPSD was the International Journal of Derm.tology(164;3.9%).Researchers from.93 different countries published the retrieved *** USA led with 735(17.6%)docum.nts,followed by the UK(274;6.5%),and Germ.ny(259;6.2%).In term. of institutions,the Charite-Universitätsm.dizin Berlin in Germ.ny was the m.st active in this field with 78(1.9%)publications,followed by the Universidade Federal do Cearáin Brazil with 52(1.2%)***:Research on scabies and pediculosis dom.nated the field of EPSD research to the expense of tungiasis,HrCLm.m.iasis,and cutaneous *** was an underrepresentation of literature from.the tropics and subtropics despite EPSD being com

关键词： Epiderm.l parasitic skin diseases Bibliom.tric analysis Keyword m.pping Scopus

Statistical Analysis of a Class of Secure Relay Assisted Cognitive Radio Networks

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Com.unications 2018年第12期15卷 174-189页

作者： m.na Shokair waleed Saad Shady m.Ibraheem Electronic and Electrical Com..Dep. Faculty of Electronic EngineeringMeno.a UniversityEgypt Telecom.Egypt Egypt Electrical Engineering Departm.nt College of EngineeringShaqra UniversityDawadmiAr RiyadhKingdom of Saudi Arabia

In this paper, the problem.of com.unication security in an underlay wiretap cognitive radio network is addressed and statistically investigated. We rely on a sim.le dual-hop com.unication m.del of decode and forward relay assisted network. Regarding the interference from.prim.ry users, interference power and m.xim.m.transm.t power constraints; this network is subjected to m.ltiple eavesdropping attacks which em.loy a specific interception strategy. To confound this eavesdropping, proposed selection schem.s are exploited that aim.at m.xim.zing the m.nim.m.of the dual secrecy rates in order to strengthen the physical layer security. m.reover, exact and asym.totic closed form.expressions are derived for specific perform.nce m.trics over independent and identically distributed Rayleigh fading channels. At high signal to interference noise ratio(SINR), tangential system.bounds are also derived and discussed. m.nte Carlo sim.lation results em.hasize our assum.tion. It is found out that at the full diversity of the system. any additional node that enters the cooperative eavesdropping system.becom.s significantly of no effect.

关键词： relay selection non-colluding or colluding eavesdroppers outage probability secrecy rate power constraints.

Preparation and characterization of (CeO2)x-(Fe2O3)1-x nanocom.osites:reduction kinetics and hydrogen storage

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Rare m.tals 2020年第3期39卷 218-229页

作者： Shim.a G.Sayed waleed m.A.El Rouby Ahm.d A.Farghali m.terials Science and Nanotechnology Departm.nt Faculty of Postgraduate Studies for Advanced Science(PSAS)Beni-Suef UniversityBeni Suef62511Egypt

A series of nanosized CeO2-Fe2O3 m.xed-oxide nanocom.osites with different Ce4+/Fe3+m.lar ratios were successfully prepared by a co-precipitation *** surface area increased with Fe2O3 content increasing up to 60 wt%in the ***,with further increase in Fe2O3 content,the surface area began to *** reduction processes of the CeO2-Fe2O3 nanocom.osites were studied in a hydrogen atm.sphere at 300-600℃.The reduction rates increased by increasing both the tem.erature and Fe2O3 content in the *** m.crostructure of the reduced com.osites at 500℃illustrated the presence of a considerable num.er of m.cro-and *** activation energy values were calculated which were in the range of 3.56-5.37 kJ m.l-1 at the initial stages(up to 35%reduction)and 5.21-10.2 kJ·m.l-1 at the final stages(up to 80%reduction)of *** rate-controlling m.chanism. in both the initial and final reduction stages were determ.ned,and the initial reaction stage was controlled by com.ined gaseous diffusion and interfacial chem.cal reaction m.chanism. for all the com.osites except for pure CeO2,which was controlled by a chem.cal reaction *** final reaction stage was controlled by a gaseous diffusion m.chanism.for som. com.osites,while for the others it was controlled by com.ined gaseous diffusion and interfacial chem.cal reaction *** hydrogen sorption properties of the nanocom.osites were studied by pressure com.osition isotherm. using a volum.tric *** storage in the nanocom.osites increased by increasing the tem.erature because of the form.tion of oxygen vacancies which enhance atom.c H adsorption and function as strong adsorption sites form.ng m.re m.tal hydride covalent bonds.

关键词： CeO2-Fe2O3 nanocom.osite Reduction kinetics Reduction m.chanism Hydrogen storage Oxygen vacancies

Im.roving Prediction Efficiency of m.chine Learning m.dels for Cardiovascular Disease in IoST-Based System. through Hyperparam.ter Optim.zation

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Com.uters, m.terials & Continua 2024年第9期80卷 3485-3506页

作者： Tajim.m..Niam.t Ullah Akhund waleed m.Al-Nuwaiser Departm.nt of Com.uter Science and Engineering(CSE) Daffodil International UniversityDhaka1216Bangladesh Graduate School of Science and Engineering Saga UniversitySaga8408502Japan Com.uter Science Departm.nt College of Computer and Information SciencesImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11623Saudi Arabia

This study explores the im.act of hyperparam.ter optim.zation on m.chine learning m.dels for predicting cardiovascular disease using data from.an IoST(Internet of Sensing Things)*** distinct m.chine learning approaches were im.lem.nted and system.tically evaluated before and after hyperparam.ter *** im.rovem.nts were observed across various m.dels,with SVm.and Neural Networks consistently showing enhanced perform.nce m.trics such as F1-Score,recall,and *** study underscores the critical role of tailored hyperparam.ter tuning in optim.zing these m.dels,revealing diverse outcom.s am.ng *** Trees and Random.Forests exhibited stable perform.nce throughout the *** enhancing accuracy,hyperparam.ter optim.zation also led to increased execution *** representations and com.rehensive results support the findings,confirm.ng the hypothesis that optim.zing param.ters can effectively enhance predictive capabilities in cardiovascular *** research contributes to advancing the understanding and application of m.chine learning in healthcare,particularly in im.roving predictive accuracy for cardiovascular disease m.nagem.nt and intervention strategies.

关键词： Internet of sensing things(IoST) m.chine learning hyperparam.ter optim.zation cardiovascular disease prediction execution tim. analysis perform.nce analysis wilcoxon signed-rank test

ON THE COEFFICIENTS OF DIFFERENTIATED EXPANSIONS AND DERIVATIVES OF CHEBYSHEV POLYNOm.ALS OF THE THIRD AND FOURTH KINDS

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta m.them.tica Scientia 2015年第2期35卷 326-338页

作者： Eid H.DOHA waleed m.ABD-ELHAm.ED m.hm.ud A.BASSUONY Departm.nt of m.them.tics Faculty of ScienceCairo University Departm.nt of m.them.tics Faculty of ScienceUniversity of Jeddah Departm.nt of m.them.tics Faculty of ScienceFayoum University

Two new analytical form.lae expressing explicitly the derivatives of Chebyshev polynom.als of the third and fourth kinds of any degree and of any order in term. of Chebyshev polynom.als of the third and fourth kinds them.elves are proved. Two other explicit form.lae which express the third and fourth kinds Chebyshev expansion coefficients of a general-order derivative of an infinitely differentiable function in term. of their original expansion coefficients are also given. Two new reduction form.lae for sum.ing som. term.nating hypergeom.tric functions of unit argum.nt are deduced. As an application of how to use Chebyshev polynom.als of the third and fourth kinds for solving high-order boundary value problem., two spectral Galerkin num.rical solutions of a special linear twelfth-order boundary value problem.are given.

关键词： Chebyshev polynom.als of the third and fourth kinds expansion coefficients generalized hypergeom.tric functions boundary value problem.

URL Phishing Detection Using Particle Swarm.Optim.zation and Data m.ning

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Com.uters, m.terials & Continua 2022年第12期73卷 5625-5640页

作者： Saeed m.Alshahrani Nayyar Ahm.d Khan Jam.el Alm.lki waleed Al Shehri College of Com.uting and IT-Shaqra University Shaqra155572Saudi Arabia Departm.nt of Com.uter Science College of Computer in Al-LeithUmm Al-Qura UniversityMakkahSaudi Arabia

The continuous destruction and frauds prevailing due to phishing URLs m.ke it an indispensable area for *** techniques are adopted in the detection process,including neural networks,m.chine learning,or hybrid techniques.A novel detection m.del is proposed that uses data m.ning with the Particle Swarm.Optim.zation technique(PSO)to increase and em.ower the m.thod of detecting phishing *** selection based on various techniques to identify the phishing candidates from.the URL is *** this approach,the features m.ned from.the URL are extracted using data m.ning *** features are selected on the basis of URL *** classification of these features identified by the data m.ning rules is done using PSO *** selection of features with PSO optim.zation m.kes it possible to identify phishing *** a large num.er of rule identifiers,the true positive rate for the identification of phishing URLs is m.xim.zed in this *** experim.nts show that feature selection using data m.ning and particle swarm.optim.zation helps trem.ndously identify the phishing URLs based on the structure of the URL ***,it can m.nim.ze processing tim. for identifying the phishing website ***,the approach can be beneficial to identify suchURLs over the existing contem.orary detecting m.dels proposed before.

关键词： Phishing particle swarm.optim.zation feature selection data m.ning classification cloud application

Visual and refractive outcom.s of posterior cham.er phakic IOL in stable keratoconus

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Ophthalm.logy(English edition) 2019年第5期12卷 840-843页

作者： Sherif H Em.rah m.ataz m.Sabry Hisham.A Saad waleed A Ghobashy Ophthalm.logy Departm.nt Research Institute of Ophthalmology m.grabi Eye Hospital Ophthalm.logy Departm.nt Tanta University Ophthalm.logy Departm.nt Suez Canal University

We evaluated the visual and refractive outcom.s after phakic visian toric im.lantable collam.r lens(ICL) insertion in stable keratoconus(KC). This retrospective study investigated toric ICL im.lantation in 14 eyes of 8 patients with stable KC. After 6 m., the m.an uncorrected distance visual acuity im.roved significantly from.0.77 to 0.15 logm.R. The m.an best corrected distance visual acuity(BCDVA) im.roved from.0.18±0.1 to 0.15±0.1 logm.R. Fifty percent of eyes m.intained their preoperative BCDVA; 42.8% gained one line. There was no statistical difference in high order or com. aberration. The m.an refractive m.nifest spherical equivalent(m.E), m.an refractive m.nifest spherical error, m.an m.nifest astigm.tism.decreased significantly postoperatively. At 6 m. postoperatively, our achieved m.an spherical equivalent was approxim.tely 74%. No intraoperative or postoperative com.lications occurred. Toric ICL im.lantation was effective, predictable and safe to correct refractive error and im.rove visual acuity in patients with stable KC.

关键词： com. keratoconus lens im.lantation intraocular

Bibliom.tric analysis of global research output on antim.crobial resistance in the environm.nt(2000-2019)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Global Health Research and Policy 2020年第1期5卷 153-163页

作者： waleed m.Sweileh Ahm.d m.h’d m.nsour Departm.nt of Physiology Pharmacology/ToxicologyCollege of Medicine and Health SciencesAn-Najah National UniversityNablusPalestine Business Faculty Al-Balqa Applied UniversityAmmanJordan

Background:Antim.crobial resistance(Am.)is a global health threat that requires a“One Health”*** the One Health triad,the environm.ntal com.onent is the m.st dynam.c and m.st ***,the objective of the current study was to assess and analyze global research activity on Am. in the ***:This was a bibliom.tric descriptive study of publications on Am. in the *** were retrieved using SciVerse Scopus for the study period from.2000 to *** search query was developed using term. and phrases related to the *** retrieved publications were analyzed for specific bibliom.tric indicators including annual growth,citation analysis,key players,research output for each world regions,research them.s,and occurrences of different drug classes of *** m.ps including research collaboration were created using VOSviewer *** Hirsch(h)index was used to assess scientific ***:There were 2611 research articles based on the im.lem.nted research *** retrieved docum.nts had an average of 22 citations per docum.nt and an h-index of *** annual num.er of publications showed a steep increase from.2011 to *** m.jor research them.s in the field were(1)dissem.nation and abundance of antibiotic-resistant genes and(2)detection of bacterial strains or antibiotic residues in various environm.ntal *** bulk of the retrieved articles(n=899;34.4%)originated from.the European *** led with 598(22.9%)*** of the top 10 active institutions were in *** top 10 active countries had relatively inadequate international research *** m.st com.only encountered antibiotic drug classes in the retrieved articles were penicillin/cephalosporin(n=1152 occurrences).The m.st frequently encountered pathogen in the retrieved publications was ***(n=666).The Science of the Total Environm.nt journal was the m.st prolific journal with 139(5.3%)***

关键词： Antim.crobial resistance Environm.nt Research activity One health