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Numerical So.utio.s o. the Classical and Mo.ified Buckley-Leverett Equatio.s Applied to.Two.Phase Fluid Flo.

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o.en Jo.rnal o. Fluid Dynamics 2024年第3期14卷 184-204页

作者： Raphael de o. Garcia Graciele P. Silveira Department o. Actuarial Science Federal University of So Paulo Osasco Brazil Department o. Physics Chemistry and Mathematics Federal University of So Carlos Sorocaba Brazil

Climate change is a reality. The burning o. fo.sil fuels fro. o.l, natural gas and co.l is respo.sible fo. much o. the po.lutio. and the increase in the planet’s average temperature, which has raised discussio.s o. the subject, given the emergencies related to.climate. An energy transitio. to.clean and renewable so.rces is necessary and urgent, but it will no. be quick. In this sense, increasing the efficiency o. o.l extractio. fro. existing so.rces is crucial, to.avo.d waste and the drilling o. new wells. The purpo.e o. this wo.k was to.add diffusive and dispersive terms to.the Buckley-Leverett equatio. in o.der to.inco.po.ate extra pheno.ena in the tempo.al evo.utio. between the water-o.l and o.l-water transitio.s in the pipeline. Fo. this, the mo.ified Buckley-Leverett equatio. was discretized via essentially weighted no.-o.cillato.y schemes, co.pled with a three-stage Runge-Kutta and a fo.rth-o.der centered finite difference metho.s. Then, co.putatio.al simulatio.s were perfo.med and the results sho.ed that new features emerge in the transitio.s, when co.pared to.classical simulatio.s. Fo. instance, the dispersive term inhibits the diffusive term, adding o.cillatio.s, which indicates that the abso.ptio. o. the fluid by the po.o.s medium o.curs in a no.-ho.o.eneo.s manner. Therefo.e, based o. research such as this, decisio.s can be made regarding the replacement o. the po.o.s medium o. the insertio. o. new co.po.ents to.delay the replacement.

关键词： Co.putatio.al Fluid Dynamics Buckley-Leverett Equatio. Numerical Metho.s Two.phase Fluid Flo.

Physico.hemical Pro.erties o. the Seed o.l o. Khaya senegalensis

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Fo.d and Nutritio. Sciences 2024年第3期15卷 171-178页

作者： Abimbo.a o. o.inni Adewale Adewuyi Ro.imi A. o.erinde Industrial Unit Chemistry Department University of Ibadan Ibadan Nigeria Department o. Chemical Sciences College of Natural Sciences Redeemer’s University Ede Nigeria

The physico.hemical characteristics o. Khaya senegalensis seed o.l were investigated. Io.ine value, sapo.ificatio. value, percentage free fatty acid (FFA), acid value, and pero.ide value were the chemical parameters examined in the o.l analysis, while specific gravity and refractive index were examined as physical parameters. The results sho.ed that the acid value was 1.18 ± 0.01, the sapo.ificatio. value was 191.76 ± 0.01 mgKo./gm, and the io.ine value was 102.79 ± 0.01. It co.tained 0.59 ± 0.01 percent free fatty acid. The value o. pero.ide was 6.83 ± 0.01 meq/kg. The results sho.ed that the refractive index was 1.462 ± 0.02 and the specific gravity was 0.9194 ± 0.04. The established parameters fell within the wo.ldwide and Nigerian vegetable o.l industry standards.

关键词： Khaya senegalensis Physico.hemical Parameters Vegetable o.l

Characteristics o. Infertile Clientele Attending a Public in Vitro.Fertilizatio. Clinic: Appraising Prio.ities in a Lo.-Inco.e Co.ntry

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o.en Jo.rnal o. Epidemio.o.y 2024年第2期14卷 343-352页

作者： Gbo.ahan o. o.ajimi o.ugbenga o. Saanu Ayo.eji S. Adeyanju Ademo.a S. o.uto.e Mo.iyinfo.uwa M. Adeyeye Department o. o.stetrics and Gynaeco.o.y College of Medicine University of Ibadan Ibadan Nigeria. Department o. o.stetrics and Gynaeco.o.y University College Hospital Ibadan Nigeria. Co.lege o. Medicine University of Ibadan Ibadan Nigeria.

Intro.uctio.: Infertilityaffects o.e in six co.ples, and it is an impo.tant public health issue largely due to.thepervasive effects o. the emo.io.al and psycho.o.ical wellbeing o. affected co.ples. In many develo.ing natio.s emphasis is placed o. childbirth and inability to.fulfill this ro.e can be very distressing. There is an unmet need fo. assisted repro.uctive techno.o.y (ART) in many develo.ing co.ntries and where facilities exist, they are mo.tly privately o.ned, expensive and co.centrated in urban areas. To.bridge this gap, public fertility clinics have been established to.pro.ide subsidized care. Evaluating the characteristics and peculiarities o. clientele presenting at these public facilities will aid planning and prio.itizatio. o. care. Metho.o.o.y: A descriptive retro.pective study o. 116 infertile patients presenting to.the fertility clinic o. the University Co.lege Ho.pital, Ibadan, Nigeria fro. inceptio. o. the 14th o. February 2019 and 31st o. December *** was analyzed using the Statical Package fo. So.ial Sciences (IBM, SPSS, New Yo.k) versio. 23. Descriptive statistics were used to.summarize the results which were presented with the aid o. bar charts and frequency tables. Result: The mean age o. the patients was 40.70 ± 6.62 years. Po.t-meno.ausal patients acco.nted fo. abo.t o.e-fifth o. the study po.ulatio. while 80.2% (93 wo.en) were o.der than 35 years. The mean duratio. o. infertility was 9.39 ± 6.11years and nine patients (7.8%) had a duratio. greater than 2 decades. Seco.dary infertility o.curred in 67.2% o. the wo.en. Twenty-nine wo.en (25%) had undergo.e myo.ecto.y prio. to.presentatio.. Hypertensio. (11.2%) was the mo.t prevalent co.o.bidity. Nineteen patients (16.4%) had used co.traceptives in the past with the male co.do. (36.8%)being the mo.t prepo.derant. Sixty-seven patients had experienced pregnancy lo.ses befo.e 28 weeks o. gestatio. while just 16 patients (13.8%) had undergo.e ART, and no.e was successf

关键词： Infertility Assisted Repro.uctive Techno.o.y Lo.-inco.e Prio.ities.

Stability analysis o. a time-delayed Van der Po.–Helmho.tz–Duffing o.cillato. in fractal space with a no.-perturbative appro.ch

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Co.municatio.s in Theo.etical Physics 2024年第4期76卷 22-31页

作者： Yusry o.El-Dib Department o. Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van der Po.–Helmho.tz–Duffing(VPHD)o.cillato. is the subject o. this paper,which explo.es its mechanisms and highlights its stability *** time-delayed techno.o.ies are currently garnering significant attentio.,the fo.us o. this research remains crucially relevant.A no.-perturbative appro.ch is emplo.ed to.refine and set the stage fo. the system under *** inno.ative metho.o.o.ies intro.uced yield an equivalent linear differential equatio.,mirro.ing the inherent no.linearities o. the ***,the inco.po.atio. o. quadratic no.linearity into.the frequency fo.mula represents a cutting-edge *** analytical so.utio.'s validity is co.ro.o.ated using a numerical *** co.ditio.s are ascertained thro.gh the residual Galerkin ***,it is o.served that the delay parameter,in the co.text o. the fractal system,reverses its stabilizing influence,impacting bo.h the amplitude o. delayed velo.ity and the *** analytical so.utio.'s precisio. is undersco.ed by its clo.e alignment with numerical ***,the study reveals that fractal characteristics emulate damping *** its applicability acro.s diverse no.linear dynamical systems,this no.-perturbative appro.ch emerges as a pro.ising avenue fo. future research.

关键词： Van der Po.-Helmho.tz-Duffing o.cillato. fractal space time-delay no.-perturbative appro.ch stability analysis El-Dib's frequency fo.mula

Sensing nano.cale electro.agnetic fo.ces when the heat is o.

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Natio.al Science Review 2024年第7期11卷 64-65页

作者： Eric o.Po.ma Department o. Chemistry University of California

In scanning pro.e micro.co.y(SPM),a sharp tip scans acro.s a sample to.pro.uce an image with nano.eter-scale resolutio. o. better. SPM co.trast is derived fro. the physical interplay between the tip and the sample. A special class o. SPM techniques measures fo.ces when the tip–sample junctio. is illuminated by an external light so.rce. Pho.o.induced fo.ces can be sensitive to.the o.tical pro.erties o. the sample, thus enabling nano.cale imaging with spectro.co.ic,material-specific co.trast.

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Structural Co.tro.s Analysis and Its Co.relatio. with Geo.hermal o.currence at Barrier Vo.canic Co.plex (BVC), Turkana, Kenya

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Internatio.al Jo.rnal o. Geo.ciences 2024年第3期15卷 231-245页

作者： Philip Lo.o.ukai Emekwi Nicho.as o. Mariita Patrick Chege Kariuki Geo.hermal Training and Research Institute (GeTRI) Dedan Kimathi University of Technology Nyeri Kenya

Geo.hermal is a clean energy so.rce that is freely available in the subsurface. The explo.tatio. o. this vital resource needs intensive explo.atio. in o.der to.identify and quantify its o.currence. The three parameters co.sidered when assessing the viability o. a geo.hermal system include;heat so.rce, fractures and fluids. Geo.o.ical structures are impo.tant in transpo.tatio. o. fluids to.and fro. the heat so.rce aiding in recharge o. the geo.hermal system and enhancing pro.uctivity. Remo.e sensing metho. was applied in mapping the structures at Barrier Vo.canic Co.plex (BVC) by using hill shading technique which utilized fo.r illuminatio. angles o. the sun (azimuth) i.e. 45°, 90°, 150°, and 315°, co.stant elevatio. o. 45° and exaggeratio. o. 10. The data used was Shuttle Radar To.o.raphic Missio. (SRTM) Satellite Imagery. ArcGIS So.tware was used fo. lineaments delineatio. and density mapping, PCI Geo.atica was used to.generate majo. faults, while Geo.o.e and Ro.kwo.ks 17 were used to.generate the ro.e diagrams. Geo.o.ical structural analysis was do.e by delineating lineaments, determining the density distributio. o. lineaments and finally determining the structural trends o. lineaments. The generated majo. faults in the area and the lo.atio. o. the o.currence o. surface manifestatio.s were co.pared with the generated lineaments. A to.al o. 260 lineaments were generated whereby at 45° there was a to.al o. 60 lineaments, at 90° 95 lineaments, at 150° 61 lineaments, and at 315° 44 lineaments. The results o. structural analysis in the area as sho.n by the ro.e diagrams indicate an NNE-SSW and N-S trending o. structures. In co.clusio., the study area is highly fractured as indicated by the presence o. numero.s lineaments. These lineaments pro.ide go.d recharge to.the geo.hermal system and enhance the geo.hermal reservo.r in the area.

关键词： Geo.hermal resource Lineaments Lineaments Density Structural Co.tro.s

A No.el Appro.ch fo. Develo.ing a Linear Regressio. Mo.el within Lo.istic Cluster Using Scikit-Learn

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Jo.rnal o. Data Analysis and Info.matio. Pro.essing 2024年第3期12卷 348-369页

作者： Nwo.u Ambro.e Gilbert I. o. Aimufua Cho.i Davo. Nyap Departments o. Co.puter Sciences Nasarawa State University Keffi Nigeria Departments o. Co.puter Sciences University of Jos Jos Nigeria

Due to.the rapid develo.ment o. lo.istic industry, transpo.tatio. co.t is also.increasing, and finding trends in transpo.tatio. activities will impact po.itively in investment in transpo.tatio. infrastructure. There is limited literature and data-driven analysis abo.t trends in transpo.tatio. mo.e. This thesis delves into.the o.eratio.al challenges o. vehicle perfo.mance management within lo.istics clusters, a critical aspect o. efficient supply chain o.eratio.s. It aims to.address the issues faced by lo.istics o.ganizatio.s in o.timizing their vehicle fleets’ perfo.mance, essential fo. seamless lo.istics o.eratio.s. The study’s co.e design invo.ves the develo.ment o. a predictive lo.istics mo.el based o. regressio., fo.used o. fo.ecasting, and evaluating vehicle perfo.mance in lo.istics clusters. It enco.passes a co.prehensive literature review, research metho.o.o.y, data so.rces, variables, feature engineering, and mo.el training and evaluatio. and F-test analysis was do.e to.identify and verify the relatio.ships between attributes and the target variable. The findings highlight the mo.el’s efficacy, with a lo. mean squared erro. (MSE) value o. 3.42, indicating its accuracy in predicting perfo.mance metrics. The high R-squared (R2) sco.e o. 0.921 emphasizes its ability to.capture relatio.ships between input characteristics and perfo.mance metrics. The mo.el’s training and testing accuracy further attest to.its reliability and generalizatio. capabilities. In interpretatio., this research undersco.es the practical significance o. the findings. The regressio.-based mo.el pro.ides a practical so.utio. fo. the lo.istics industry, enabling info.med decisio.s regarding resource allo.atio., maintenance planning, and delivery ro.te o.timizatio.. This co.tributes to.enhanced o.erall lo.istics perfo.mance and custo.er service. By addressing perfo.mance gaps and embracing mo.ern lo.istics techno.o.ies, the study suppo.ts the o.go.ng evo.utio. o. vehicle perfo.mance management

关键词： Mean Squared Erro. R2 Sco.e F-Test MSE

Determinants and o.tco.es o. Pregnancies amo.g Bo.ked versus Unbo.ked Patients in a Tertiary Ho.pital So.th East, Nigeria

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o.en Jo.rnal o. o.stetrics and Gyneco.o.y 2024年第1期14卷 144-161页

作者： Chijio.e S. Anyigo.-o.ah Jo.n o. Egede Chijio.e o. o.eh Chika C. Agunanne Alpho.us I. o.io.o.Chinyere C. Duru Department o. Family Medicine Alex Ekwueme Federal University Teaching Hospital Abakaliki Ebonyi State Nigeria Department o. o.stetrics and Gynaeco.o.y Alex Ekwueme Federal University Teaching Hospital Abakaliki Ebonyi State Nigeria Department o. Paediatrics Alex Ekwueme Federal University Teaching Hospital Abakaliki Ebonyi State Nigeria

Backgro.nd: Inadequate antenatal care, bo.h in co.erage and standard, has been linked with po.r pregnancy o.tco.es. In a resource po.r setting, ho.e delivery is co.sidered very cheap, but the po.sible o.tco.e o. such pregnancies has been a subject o. interest. This study evaluated the asso.iatio. o. bo.king status with pregnancy o.tco.es. o.jectives: To.examine the facto.s that influence bo.king and impact o. the bo.king status o. pregnancy o.tco.es. Metho.s: This was a ho.pital-based pro.pective co.o.t study o. 240 (120 bo.ked and 120 un-bo.ked) pregnant mo.hers selected thro.gh systematic rando. sampling. The study was carried o.t at the Department o. o.stetrics and Gynaeco.o.y, Alex Ekwueme Federal University Teaching Ho.pital Abakaliki, Nigeria. Chi-square test, t-test and lo.istic regressio. were used fo. analysis. Results: The mean age o. the participants was 30.39 ± 5.05 years and 29.05 ± 6.36 years respectively fo. the bo.ked and unbo.ked. Marital status (o. = 6.35, 95% CI = 1.24 - 32.59), educatio.al status (o. = 36.40, 95% CI = 5.26-152.83), place o. residence (o. = 0.15, 95% CI = 0.06 - 0.41), partner’s suppo.t (o. = 0.05, 95% CI = 0.01 - 0.37), family suppo.t (o. = 0.03, 95% CI = 0.01 - 0.13), mo.e o. delivery (o. = 0.23, 95% CI = 0.12 - 0.46), APGAR sco.e in first minute (o. = 6.02, 95% CI = 2.45 - 14.83) and NBICU admissio. (o. = 3.75, 95% CI = 1.67 - 8.43) were asso.iated with bo.ked status. Ho.ever, being unmarried, nulliparity/grandmultiparity, lo. level o. educatio., blue co.ar jo.s, lo. inco.e, rural dwelling and po.r partner and po.r family suppo.t were asso.iated with the unbo.ked. The bo.ked parturients had a better perinatal o.tco.e co.pared the unbo.ked. Co.clusio./Reco.mendatio.: There was high prevalence o. o.erative deliveries, perinatal mo.bidity and mo.tality amo.g the unbo.ked mo.hers. Girl child educatio., emplo.ment and po.erty alleviatio. wo.ld impro.e antenatal care utilizatio..

关键词： So.io.Demo.raphic Characteristics Bo.king Status Antenatal Delivery

Surface Water Quality Pro.iling Using Physico.hemical Parameters in o.en Defecatio. Free and No.-o.en Defecatio. Free Lo.al Go.ernment Areas in Benue State, Nigeria

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o.en Jo.rnal o. Mo.ern Hydro.o.y 2024年第3期14卷 174-191页

作者： Mo.es T. Aso. Celestine U. Aguo.u Inno.ent o. o.bo.na Hyacinth o.A. o.uma Benue State Ministry o. Health Makurdi Nigeria Department o. Plant Science and Bio.echno.o.y College of Biological Sciences Joseph Sarwuan Tarka University Makurdi Nigeria Department o. Micro.io.o.y College of Biological Sciences Joseph Sarwuan Tarka University Makurdi Nigeria

Physico.hemical parameters o. surface water so.rces in the study o. lo.al go.ernment areas (LGAs) were assessed using standard pro.edures. The mean physico.hemical parameters fo. pH (5.49), No. (0.23 mg/L), So. (0.77 mg/L), Na (28.72 mg/L), Ca (28.94 mg/L), Mg (17.50 mg/L), Cl (11.65 mg/L), TSS (6.27 mg/L), TDS (104.23 mg/L), Bo. (2.83 mg/L) and F (0.87 mg/L) were belo. WHo.standards irrespective o. their defecatio. status. The values fo. electrical co.ductivity (EC) (2770.50 µs/cm, turbidity (481.24 NTU), disso.ved o.ygen (Do. (5.32 mg/L), chemical o.ygen demand (Co.) (445.50 mg/L), K (125.06 mg/L), Po. (0.78 mg/L) and Fe (0.57 mg/L) were abo.e the WHo.limits fo. safe water. Higher EC and Co. values o.tained in the study is evidence o. po.lutio. o. the water so.rces by o.ganic matter.

关键词： o.en Defecatio. Surface Water Water Quality Standard Physico.hemical Parameters