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CES Transactions on Electrical Machines and Systems 2024年第2期8卷 216-226页

作者： Mehrage Ghods Jawad Faiz ali A Pourmoosa IEEE School of Electrical and Computer Engineering College of Engineeringthe University of Tehran

The magnetic flux in a permanent magnet transverse flux generator(PMTFG) is three-dimensional(3D), therefore, its efficacy is evaluated using 3D magnetic field analysis. Although the 3D finite-element method(FEM) is highly accurate and reliable for machine simulation, it requires a long computation time, which is crucial when it is to be used in an iterative optimization process. Therefore, an alternative to 3DFEM is required as a rapid and accurate analytical technique. This paper presents an analytical model for PMTFG analysis using winding function method. To obtain the air gap MMF distribution, the excitation magneto-motive force(MMF) and the turn function are determined based on certain assumptions. The magnetizing inductance, flux density, and back-electro-magnetomotive force of the winding are then determined. To assess the accuracy of the proposed method, the analytically calculated parameters of the generator are compared to those obtained by a 3D-FEM. The presented method requires significantly shorter computation time than the 3D-FEM with comparable accuracy.

关键词： Index Terms—Permanent magnet transverse flux generator Winding function 3D-FEM Cogging torque Prototyping

Intelligent algorithm-based maximum power point tracker for an off-grid photovoltaic-powered direct-current irrigation system

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Clean Energy 2024年第3期8卷 48-61页

作者： Hussain Attia Maen Takruri ali Al-Ataby Department of Electrical Electronics and Communications EngineeringAmerican University of Ras Al KhaimahRas Al KhaimahUnited Arab Emirates

This research aims to enhance the performance of photovoltaic(PV)systems on a 2-fold ***,it introduces an advanced deep artificial neural network algorithm for accurate and fast maximum power point tracking,ensuring optimal extraction of electrical power from PV ***,it proposes the use of 96-V,2.98-kW direct-current(DC)water pumps for farm irrigation,aiming to improve efficiency,reduce cost and complexity,and overcome challenges associated with connecting faraway farm irrigation systems to the utility *** this study,it has been demonstrated that the use of DC pumps greatly improves system performance and efficiency by eliminating the need for isolation transformers,power passive filters and inverters,therefore simplifying the architecture of the *** efficacy of the proposed methodology is confirmed by MATLAB®/Simulink®simulation results,whereby the proposed algorithm attains a mean squared error of 6.5705×10^(-5)and a system efficiency approaching 99.8%,ensuring a steady voltage under varying load conditions.

关键词： artificial neural network photovoltaic arrays maximum power point tracking buck converter direct-current irrigation systems MATLAB/Simulink

Tubular Heat Enhancement Using Twisted Tape Inserts with Large Holes

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Energy Engineering 2024年第2期121卷 273-290页

作者： ali Jaber Abdulhamed Aws Al-Akam Wisam J.Khudhayer ali Sabri Allw Faculty of Engineering-Al-Mussayib University of BabylonHillaBabylon15001Iraq

Heat augmentation techniques play a vital role in the heating and cooling processes in industries,including solar collectors and many applications that utilize heat *** studies are based on inserting fillers inside the tubes to enhance heat *** investigation considered the effects of twisted tapes with large holes on a tubular heat exchanger’s(HX)heat transmission,pressure drop,and thermal boosting *** the experimental section,counter-swirl flow generators used twisted tapes with pairs of 1.0 cm-diameter holes and changes in porosity(Rp)at 1.30%and 2.70%.In the experiments,air was utilized as a working fluid in a tube with a circular *** turbulent flow was considered,with Reynolds numbers(Re)domain from 4800 to 9500,and a boundary condition with a uniform wall heat flux was *** findings expound that when the number of holes rose,the Nusselt number(Nu),the factor of friction(f),and the thermal enhancement factor(η)all increased as ***,as the friction factor increased,the Nusselt number of the tape-equipped tube was noticeably ***,it was discovered that the friction factor was between 70%and 94%lower than the values of the tube without tape,while the(Nu)was between 87%and 97%higher than the conventional tube *** maximum value ofηis 89%.According to the experimental results,empirical correlations for Nu,f,andηwere also generated.

关键词： Tubular heat exchanger tape inserts twisted tape

Green hydrogen energy production:current status and potential

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Clean Energy 2024年第2期8卷 1-7页

作者： ali O.M.Maka Mubbashar Mehmood The Libyan Centre for Research and Development of Saharian Communities MurzuqLibya School of Engineering and Physical Sciences Heriot-Watt UniversityEdinburghEH144ASUK

The technique of producing hydrogen by utilizing green and renewable energy sources is called green hydrogen ***,by implementing this technique,hydrogen will become a sustainable and clean energy source by lowering greenhouse gas emissions and reducing our reliance on fossil *** key benefit of producing green hydrogen by utilizing green energy is that no harmful pollutants or greenhouse gases are directly released throughout the ***,to guarantee all of the environmental advantages,it is crucial to consider the entire hydrogen supply chain,involving storage,transportation and end *** is a promising clean energy source and targets plan pathways towards decarbonization and net-zero emissions by *** paper has highlighted the techniques for generating green hydrogen that are needed for a clean environment and sustainable energy ***,it summarizes an overview,outlook and energy transient of green hydrogen ***,its perspective provides new insights and research directions in order to accelerate the development and identify the potential of green hydrogen production.

关键词： green hydrogen energy hydrogen production energy transition clean energy perspective of green hydrogen

Study of bending angle and shadow in a new Schwarzschild-like black hole affected by plasma and non-plasma mediums

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Chinese Physics C 2024年第5期48卷 309-318页

作者： Riasat ali Tiecheng Xia Muhammad Awais Rimsha Babar Department of Mathematics Newtouch Center for Mathematics of Shanghai UniversityShanghai 200444China Department of Mathematics University of Engineering and Technology Lahore-54890Pakistan Department of Mathematics GC University Faisalabad Layyah CampusLayyah-31200Pakistan

In this study,we analyze the models of the deflection angle of a new Schwarzschild-like black hole(BH)and employ the optical metric of the *** achieve this,we use the Gaussian curvature of the optical metric and the Gauss-Bonnet theorem,known as the Gibbons-Werner technique,to determine the deflection ***,we examine the deflection angle in the presence of a plasma medium and the effect of the plasma medium on the deflection *** deflection angle of the BH solution in the gauged super-gravity is computed using the Keeton-Petters *** the ray-tracing technique,we investigate the shadow of the corresponding BH and analyze the plots of the deflection angle and shadow to verify the influence of the plasma and algebraic thermodynamic parameters on the deflection angle and shadow.

关键词： new Schwarzschild-like black hole Gibbons-Werner and Keeton-Petters techniques deflection angle ray-tracing approach shadow

Seasonal variations in dissolved organic matter concentration and composition in an outdoor system for bank filtration simulation

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Journal of Environmental Sciences 2024年第1期135卷 252-261页

作者： Muhammad Zeeshan Omamah ali Shamas Tabraiz Aki Sebastian Ruhl German Environment Agency Section II 3.3Schichauweg 5812307BerlinGermany Technische Universitat Berlin Water TreatmentKF4Str.des 17.Juni 13510623BerlinGermany Natural and Applied Sciences Section School of Psychology and Life SciencesCanterbury Christ Church UniversityCanterburyCT11QUUK

Dissolved organic matter(DOM)in surface waters can vary markedly in character depending on seasonal variations such as rainfall intensity,UV radiations and *** in DOM as well as temperature and rainfall intensity over the year can affect the biochemical processes occurring in bank filtration(BF).Identification and characterization of DOM in the surface water could help to optimize the water treatment and provide stable and safe drinking *** study investigated year-long variations of DOM concentrations and compositions in a surface water of a circulated outdoor pond(research facility)connected to a BF *** was dominated by humic substances and a changing pattern of DOM in surface water was observed throughout the year.A significant increase of DOM(~38%)in surface water was noted in August compared to *** fluorescent DOM showed that DOM in summer was enriched with the degradable fraction whilst non-degradable fraction was dominated in winter.A constant(1.7±0.1 mg/L)effluent DOM was recirculated in the system throughout the *** removal through BF varied between 4%to 39%and was achieved within a few meters after infiltration and significantly correlated with influent DOM concentration(R^(2)=0.82,p0.05)change in the removal of DOM was observed in two subsurface layers(upper and lower).This study highlights the presence of a constant non-degradable DOM in the bank filtrate,which was not affected by temperature,redox conditions and UV radiations.

关键词： Bank filtration Dissolved organic matter Dissolved oxygen Fluorescence spectroscopy Excitation-emission matrix

Compression properties of cost-efficient porous expanded clay reinforced AA7075 syntactic foams fabricated by industrial-oriented die casting technology

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China Foundry 2024年第1期21卷 60-70页

作者： İsmail Cem Akgün Çağın Bolat ali Gökşenli Faculty of Mechanical Engineering Istanbul Technical University34437İstanbulTurkey Faculty of Engineering Samsun University55420SamsunTurkey

In today’s manufacturing industries,hard competition between rival firms makes it compulsory for researchers to design lighter and cheaper machine components due to the megatrends of cost-effectiveness and *** this point,aluminum syntactic foams(ASFs)are new-generation engineering composites and come into the upfront as a *** to their features like low density,sufficient elongation,and perfect energy absorption ability,these advanced foams have been considerably seductive for many industrial sectors *** this study,an industrial-oriented automatic die casting technology was used for the first time to manufacture the combination of AA7075/porous expanded clay(PEC).Micro evaluations(optical and FESEM)reveal that there is a homogenous particle distribution in the foam samples,and inspections are compatible with the other ASF ***,T6 aging heat treatment was operated on one half of the produced foams to explore the probable impact of aging on the compressive *** results show that PEC particles can be an alternative to expensive hollow spheres used in the previous ***,a favorable relationship is ascertained between the aging treatment and mechanical properties such as compression strength and plateau strength.

关键词： die casting porous materials metal matrix sytanctic foams expanded clay compressive deformation

Defining failure of endoluminal biliary drainage in the era of endoscopic ultrasound and lumen apposing metal stents

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World Journal of Gastroenterology 2024年第29期30卷 3534-3537页

作者： Faisal S ali Sushovan Guha Department of Gastroenterology Hepatologyand NutritionUniversity of Texas Health Science Center at HoustonHustonTX 77054United States Department of Clinical Sciences Tilman J.Fertitta Family College of MedicineUniversity of HoustonHoustonTX 77204United States

The role of endoscopy in pathologies of the bile duct and gallbladder has seen notable advancements over the past two *** advancements in stent technology,such as the development of lumen-apposing metal stents,and adoption of endoscopic ultrasound and electrosurgical principles in therapeutic endoscopy,what was once considered endoscopic failure has transformed into failure of an approach that could be salvaged by a second-or third-line endoscopic *** of these advancements in routine patient care will require formal training and multidisciplinary acceptance of established techniques and collaboration for advancement of experimental techniques to generate robust evidence that can be utilized to serve patients to the best of our ability.

关键词： Endoscopic ultrasound Guided biliary drainage Gallbladder Biliary obstruction Lumen-apposing metal stent

Clean production of lactic acid by selective carbon-carbon bond cleavage of biomass feedstock over a novel carbon-bismuth oxychloride photocatalyst

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 69-81页

作者： Zulfiqar ali Jiliang Ma Dongnv Jin Rui Cui Runcang Sun Liaoning Key Lab of Lignocellulose Chemistry and Biomaterials Liaoning Collaborative Innovation Center for Lignocellulosic BiorefineryCollege of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian 116034China

The use of functional materials such as carbon-bismuth oxyhalides in integrated photorefineries for the clean production of fine chemicals requires restructuring.A facile biomass-assisted solvothermal fabrication of carbon/bismuth oxychloride nanocomposites(C/BiOCl)was achieved at various *** with BiOCl and C/BiOCl-120,C/BiOCl-180 exhibited higher crystallinity,wider visible light absorption,and a faster migration/separation rate of photoinduced *** the selective C–C bond cleavage of biomass-based feedstocks photocatalyzed by C/BiOCl-180,the xylose conversion and lactic acid yield were 100%and 92.5%,respectively.C/BiOCl-180 efficiently converted different biomass-based monosaccharides to lactic acid,and the efficiency of pentoses was higher than that of ***,lactic acid synthesis was favored by all active radicals including superoxide ion(·O_(2)^(−)),holes(h^(+)),hydroxyl radical(·OH),and singlet oxygen(^(1)O_(2)),with·O_(2)^(−)playing a key *** fabricated photocatalyst was stable,economical,and *** use of biomass-derived monosaccharides for the clean production of lactic acid via the C/BiOCl-180 photocatalyst has opened new research horizons for the investigation and application of C–C bond cleavage in biomass-based feedstocks.

关键词： carbon-carbon bond cleavage biomass reforming C/BiOCl lactic acid photocatalysis

Demystifying energy savings from dynamic temperature setpoints under weather and occupancy variability

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Energy and Built Environment

Energy and Built Environment 2024年第6期5卷 878-888页

作者： Riccardo Talami Ilyas Dawoodjee ali Ghahramani Department of the Built Environment National University of SingaporeSingapore 117566

Building temperature setpoints affect both HVAC energy consumption and occupant *** reduce HVAC energy usage,researchers often investigate how system operations can be optimized under weather and occupancy variability subject to a fixed setpoint that minimizes any possible *** previous research has explored the selection of dynamic setpoints to minimize HVAC energy consumption based on outdoor temperature,they have often neglected the impact of varying occupancy rates on the *** paper aims to demystify energy savings derived from fixed and dynamic temperature setpoints under weather and occupancy variability and explores the additional energy savings that can be achieved through dynamic temperature *** exhaustive HVAC zone temperature setpoint optimizer was developed to determine dynamic setpoints with respect to weather and occupancy(i.e.,setpoints that minimize HVAC energy consumption at different occupancy rates based on outdoor weather).*** reference building energy models for small,medium,and large office buildings were simulated at 17 climate zones,4 occupancy rates(25%,50%,75%,100%)and 7 setpoints(19.5℃to 25.5℃at 1℃interval).It was found that,both fixed and dynamic setpoints benefit from the energy reduction of approximately 2-4%from the lower heat generated by the occupants at lower occupancy ***,at outdoor temperatures between 5℃and 32℃where occupant heat loads can swing the building between heating,free-running,and cooling modes,dynamic setpoints yield additional 2-10%energy savings,compared to fixed setpoints.

关键词： Decarbonization Smart buildings Optimization Occupancy Heat loads