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Investigatio.s into.the Mo.pho.etric Characteristics o. o.ibia Drainage Basin, Awka Urban Area, Nigeria

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o.en Jo.rnal o. Mo.ern Hydro.o.y 2018年第1期8卷 1-12页

作者： Emma E. ezenwaji Emmanuel o. Nwabineli philip o. phil-eze Nnamdi Azikiwe University Awka Nigeria Akanu Ibiam Federal Po.ytechnic Unwana Nigeria University o. Nigeria Nsukka Nigeria

The aim o. the study was to.investigate the mo.pho.etric characteristics o. o.ibia drainage basin which is who.ly lo.ated within the Awka Capital territo.y o. Anambra State, Nigeria. The basin was delineated with co.ventio.al metho. fro. to.o.raphic map (Udi SW) o. the scale o. 1:50,000 published by Federal Survey o.fice. Field survey was co.ducted fo. 9 mo.ths between April and December 2015 and data were o.tained o. linear, areal and relief aspects o. the basin to.ascertain the mo.pho.etric characteristics o. the basin. Principal Co.po.ent Analysis (PCA) reduced o.r 19 variables into.5 while Principal Co.po.ent Regressio. (PCR) was emplo.ed to.reveal the relative co.tributio.s o. mo.pho.etric variables. Result sho.s a bifurcatio. Ratio.R (Rb) o. 3.00 aro.nd the mo.th o. the river basin indicating higher risk o. flo.ding. The relatio.ship between mean stream length and stream o.der sho.s that o.der 2 drifts to. far away fro. straight line o. plo.ted graph suggesting so.e structural imbalances. The study reco.mends pro.er urban land use planning within the basin that wo.ld preserve the natural co.ditio. o. the basin.

关键词： Mo.pho.etry Basin Relief River Land Use

An Analysis o. the Cycles and Perio.icities o. Annual Rainfall o.er Awka Regio., Nigeria

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Atmo.pheric and Climate Sciences 2014年第4期4卷 665-671页

作者： Emma E. ezenwaji philip o. phil-eze Ifeanyi C. Enete Bernard o. o.uiwu Department o. Geo.raphy and Meteo.o.o.y Nnamdi Azikiwe University Awka Nigeria Department o. Geo.raphy University of Nigeria Nsukka Nigeria

The aim o. this study was to.analyse the cycles and perio.icities o. annual rainfall o.er Awka regio., Nigeria. This is necessitated by the fact that, despite the fact that wet years co.tribute greatly to.annual flo.ding and gully ero.io. o.served in the area, researches o. cycles and perio.icities o. rainfall in the area are o.vio.sly lacking. This research is, therefo.e, an attempt to.clo.e this gap in kno.ledge. 35 years rainfall data (1975-2010) were co.lected fro. the Nigerian Meteo.o.o.ical Agency (NIMET) Lago. fro. which harmo.ic calculatio. was made using Harmo.ic Analytical Technique. The mo.el pro.uced 13 harmo.ics (cycles) o. which tho.e o. 1, 6 and 11 with amplitudes o. 181.66 mm, 149.42 mm and 126.63 mm and perio.icities o. 35, 5.20 and 2.84 were iso.ated as mo.t impo.tant. All calculatio.s were perfo.med using MINITAB versio. 16 statistical pro.ramme running under PC/Windo.s 98. Fo.lo.ing fro. the findings, it was suggested that Urban and Regio.al Planners, Geo.o.ho.o.ists and Engineers co.ld use the result to.develo. a flo.d and ero.io. management plan fo. the area.

关键词： Co.po.ent Fo.matting Style Styling

Spatio.empo.al Characteristics o. Wetlands Eco.ystem in the Niger Delta Regio.

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Jo.rnal o. Geo.cience and Enviro.ment Pro.ectio. 2021年第12期9卷 244-264页

作者： Wali Elekwachi philip o. phil-eze Etiese A. Etuk Co.lins H. Wizo. Chinedu J. o.yishi Department o. Geo.raphy University of Nigeria University Road Nsukka Enugu State Nigeria Clean Nigeria Asso.iates Limited/Gte Arco. Shed 1 Nigeria Ports Authority Port Harcourt Rivers State Nigeria Department o. Geo.raphy and Enviro.mental Management University of Port-Harcourt Choba Port-Harcourt Nigeria

Wetlands are classified as essential and valuable co.po.ents o. the eco.ystem. Wetlands are significant fo. eco.ystem services such as nutrient cycles, so.l fo.matio. and water treatment. Nearly half o. the wo.ld’s wetlands have vanished in the last century because o. anthro.o.enic activities, agricultural land use, and urban develo.ment, o.e o. such places that are faced with the challenges o. sustainability is the wetland habitats. This study aimed at assessing the spatial tempo.al characteristics o. wetlands eco.ystem in the Niger Delta Regio. o. Nigeria fro. 1986-2016. The seco.dary data include raw satellite imageries o.tained fro. the archive o. the United States Geo.o.ical Survey and Earth Explo.er. The data set includes a no.able perio. o. fo.r years landsat images fo., 1986, 1996, 2006 and 2016. The maps were pro.ected using Universal Transverse Mercato. (UTM) pro.ectio. system and datum WGS 84 o. zo.e 32. Satellite images o. the study area were acquired fro. the United States Geo.o.ical Survey (USGS). The USGS uses the LandSat5 Thematic Mapper (TM) Landsat7 Thematic Mapper, Enhanced Thematic Mapper (ETM+), Thermal Infrared Senso. (TIRS) and Landsa8 o.eratio.al Land Imager (o.I) to.generate high reso.utio. images that are useful fo. this type o. study. The satellite imageries were also.analyzed using GIS and Remo.e Sensing techniques by co.puting o. No.malized Differential Vegetatio. Index (NDVI) values fo. the entire study area by co.versio. o. spectral reflectance values into.NDVI values. The satellite images covering the area were acquired and analyzed using ArcGIS10.6. A total area of 25,053.93 (km2) was delineated in the study area. After processing the imagery, five land use/land cover (LULC) classes were developed in ArcGIS environment, such as Built-up area, Fallo. land, Vegetatio., Wetland and Waterbo.y.

关键词： Wetland Eco.ystem Land Co.er Multiple Linear Regressio. Analysis GIS Remo.e Sensing

Green hydro.en energy pro.uctio.: current status and po.ential

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CLEAN ENERGY 2024年第2期8卷 1-7页

作者： Maka, Ali o. M. Mehmo.d, Mubbashar Libyan Ctr Res & Dev Saharian Co.munities Murzuq Libya Herio. Watt Univ Sch Engn & Phys Sci Edinburgh EH14 4AS Scotland

The technique o. pro.ucing hydro.en by utilizing green and renewable energy so.rces is called green hydro.en pro.uctio.. Therefo.e, by implementing this technique, hydro.en will beco.e a sustainable and clean energy so.rce by lo.ering greenho.se gas emissio.s and reducing o.r reliance o. fo.sil fuels. The key benefit o. pro.ucing green hydro.en by utilizing green energy is that no.harmful po.lutants o. greenho.se gases are directly released thro.gho.t the pro.ess. Hence, to.guarantee all o. the enviro.mental advantages, it is crucial to.co.sider the entire hydro.en supply chain, invo.ving sto.age, transpo.tatio. and end users. Hydro.en is a pro.ising clean energy so.rce and targets plan pathways to.ards decarbo.izatio. and net-zero.emissio.s by 2050. This paper has highlighted the techniques fo. generating green hydro.en that are needed fo. a clean enviro.ment and sustainable energy so.utio.s. Mo.eo.er, it summarizes an o.erview, o.tlo.k and energy transient o. green hydro.en pro.uctio.. Co.sequently, its perspective pro.ides new insights and research directio.s in o.der to.accelerate the develo.ment and identify the po.ential o. green hydro.en pro.uctio.. Hydro.en is a pro.ising clean energy so.rce and a pathway to.ards decarbo.izatio. and net-zero.emissio.s by 2050. This article pro.ides perspective o. techniques fo. generating green hydro.en that are needed fo. a clean enviro.ment and sustainable energy so.utio.s. Graphical Abstract

关键词： green hydro.en energy hydro.en pro.uctio. energy transitio. clean energy perspective o. green hydro.en TECHNo.o.IES Ro.DMAP

Experimental study o. influence o. blade angle and particle size o. particle mechanics o. a batch-o.erated single flo.r o. a multiple hearth furnace

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Particuo.o.y 2024年第2期85卷 224-240页

作者： Max Kriegesko.te Niko.ine Hilse phil Spatz Vikto. Scherer Institute fo. Energy Plant Techno.o.y(LEAT) Ruhr University BochumUniversitätsstraβe 15044780 BochumGermany

In industry,multiple hearth furnaces are used fo. the thermal treatment o. particulate *** current co.tributio. co.centrates o. the experimental analysis o. particle mechanics fo. a batch-o.erated single flo.r o. a multiple hearth *** particles are agitated o. the circular flo.r by a single,ro.ating rabble arm equipped with three flat rabble blades o. 10 mm *** blade angle,defined as the angle,which the blade is inclined against the tangential directio.,is varied fro. 0°to.90°.A single layer o. spherical po.yo.ymethylene(Po.)particles with three different diameters(5,10 and 20 mm)is placed o. the *** analyze the results,two.parameters have been extracted fro. image analysis when the bed o. particles is agitated,first,the area no. co.ered by particles and seco.d,the frequency distributio. o. the mean distance amo.g the *** particle free surface area increases with the inclinatio. o. the *** evo.utio. o. the particle free surface area differs fo. the different particle *** general,the maximum particle free area fo. all blade angles is the largest fo. the 5 mm particles fo.lo.ed by the 20 mm *** the 10 mm particles,the particle free surface area starts fo. a blade angle o. 0°at larger values than fo. the 20 mm particles but the values fall belo. the values fo. the 20 mm particles fo. larger blade *** reaso. fo. this behavio. is discussed in *** mean distance amo.g the particles is a parameter characterizing the length scales do.inating the effects o. the *** frequency distributio. o. the mean distance amo.g particles pro.ides info.-matio. abo.t the mo.pho.o.y o. the particle bulk,fo. example,whether the free surface area is inter-spersed with particles.

关键词： Hearth furnace flo.r Particle mo.ement Spherical particles Particle free surface area Mean distance amo.g particles

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 reso.rce 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 Reso.rce Lineaments Lineaments Density Structural Co.tro.s

Light-defo.mable micro.o.o.s shape up fo. the bio.o.ical o.stacle co.rse

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Light(Science & Applicatio.s) 2024年第5期13卷 803-805页

作者： philip Wijesinghe Centre o. Bio.ho.o.ics SUPASchool of Physics and AstronomyUniversity of St AndrewsNorth HaughSt AndrewsFife KY169SSUK

Euglena gracilis micro.lga has been transfo.med into.a so.t bio.micro.o.o. with light-co.tro.led mo.io. and defo.matio. that can address diverse bio.challenges,such as drug delivery,diseased cell remo.al,and pho.o.yna... 详细信息

关键词： Euglena transfo.med o.stacle

A hybrid so.ar-bio.as system fo. po.t-Co.ID-19 rural energy access

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CLEAN ENERGY 2024年第1期8卷 84-99页

作者： o.eren, o.huko.K. o.ileke, Kechrist Meyer, Edso. L. Makaka, Go.den Apeh, o.iver o. Univ Ft Hare Ft Hare Inst Technol Private Bag X1314 ZA-5700 Alice South Africa Univ Ft Hare Renewable Energy Res Ctr Dept Phys Private Bag X1314 ZA-5700 Alice South Africa Univ Jo.annesburg Fac Engn & Build Environm Dept Elect & Elect Engn Sci ZA-2006 Auckland Pk South Africa

So.ar ho.e systems fo. rural electrificatio. are o.ten designed with a limited energy supply, which presents a drawback fo. the techno.o.y. Furthermo.e, unco.tro.led livesto.k faeces in rural co.munities co.stitute enviro.mental sanitatio. and health risks. Livesto.k excrement can be used thro.gh a bio.as digester to.supplement so.ar energy to.pro.ide adequate and sustainable electricity access to.underserved rural co.munities while achieving waste management. Therefo.e, this study presents a hybrid so.ar-bio.as system fo. a mo.e dynamic energy supply and waste management fo. po.t-Co.id reco.ery plans in rural co.munities. A parametric research appro.ch that invo.ves the use o. the Integrated Enviro.ment So.utio. Virtual Enviro.ment so.tware applicatio. and mathematical mo.els to.design the desired ho.seho.d lo.d and the hybrid system sizing is used in the study. The findings sho. that the daily ho.seho.d energy co.sumptio. was 6.6 kWh, equivalent to.206.40 kWh/mo.th. A 1.2-kWp and 1.2-m3 hybrid so.ar-bio.as system was fo.nd to.adequately po.er the ho.se. Financially, the to.al initial investment co.t o. the system was $5777.20 with a net present value o. $6566.78, net pro.it o. $4443.6, a payback perio. o. 14 years and 8 mo.ths, and a levelized co.t o. energy o. $0.21/kWh; these include a 60% initial investment and maintenance co.ts subsidy. Energy perfo.mance co.tracting and energy-as-a-service were reco.mended to.effectively run and o.erate the system. The study successfully revealed the design, specificatio.s and upscaling mechanism o. the pro.o.ed hybrid so.ar-bio.as system. Mo.e research is required to.unveil the efficacy o. the system, the perfo.mance gap and the perceptio. o. the techno.o.y by the beneficiaries. A hybrid so.ar-bio.as system is designed fo. a mo.e dynamic energy supply and waste management fo. po.t-Co.id reco.ery plans in rural co.munities. A parametric research appro.ch is used to.specify the desired ho.seho.d lo.d and the hybrid system sizi

关键词： energy access sustainable rural develo.ment clean energy waste management po.t-Co.ID-19 reco.ery plan So.TH-AFRICA ELECTRIFICATIo. BATCH

A framewo.k fo. dynamic mo.elling o. railway track switches co.sidering the switch blades,actuato.s and co.tro. systems

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Railway Engineering Science 2024年第2期32卷 162-176页

作者： Saikat Dutta Tim Harriso. Christo.her Ward Ro.er Dixo. phil Winship Institute o. Thermo.luids School of Mechanical EngineeringUniversity of LeedsLeedsWest YorkshireUK Wo.fso. Scho.l o. Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughboroughLeicestershireUK Birmingham Centre fo. Railway Research and Educatio. School of EngineeringUniversity of BirminghamBirminghamWest MidlandsUK Netwo.k Rail Milton KeynesBuckinghamshireUK

The main co.tributio. o. this paper is the develo.ment and demo.stratio. o. a no.el metho.o.o.y that can be fo.lo.ed to.develo. a simulatio. twin o. a railway track switch system to.test the functio.ality in a digital *** is impo.tant because,glo.ally,railway track switches are used to.allo. trains to.change ro.tes;they are a key part o. all railway ***,because track switches are single po.nts o. failure and safety-critical,their inability to.o.erate co.rectly can cause significant delays and co.co.itant *** o.der to.better understand the dynamic behavio.r o. switches during o.eratio.,this paper has develo.ed a full simulatio. twin o. a co.plete track switch *** appro.ch fuses finite element fo. the rail bending and mo.io.,with physics-based mo.els o. the electro.echanical actuato. system and the co.tro. ***,it pro.ides researchers and engineers the o.po.tunity to.explo.e and understand the design space aro.nd the dynamic o.eratio. o. new switches and switch machines befo.e they are *** is useful fo. lo.king at the mo.ificatio. o. mo.ito.ing o. existing switches,and it beco.es even mo.e impo.tant when new switch co.cepts are being co.sidered and *** simulatio. is capable o. running in real time o. faster meaning designs can be iterated and checked *** paper describes the mo.elling appro.ch,demo.strates the metho.o.o.y by develo.ing the system mo.el fo. a no.el“REPo.NT”switch system,and evaluates the system level perfo.mance against the dynamic perfo.mance requirements fo. the *** the co.text o. that case study,it is fo.nd that the pro.o.ed new actuatio. system as designed can meet(and exceed)the system perfo.mance requirements,and that the fault to.erance built into.the actuatio. ensures co.tinued o.eratio. after a single actuato. failure.

关键词： Railway track switch Mathematical mo.elling Redundant actuatio. Finite element analysis