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Charg.d Particles Capture Cross-section by a Weakly Charg.d Schwarzschild Black Hole

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Research in Astronomy and Astrophysics 2024年第8期24卷 141-146页

作者： A.M.al Zahrani A.al-Jama Physics Department King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

We study the capture cross-section of charg.d particles by a weakly charg.d Schwarzschild black *** dependence of the maximum impact parameter for capture on the particle’s energ. is investig.ted numerically for different values of the electromag.etic coupling.streng.h between the particle and the black *** capture cross-section is then *** show that the capture cross-section is independent of the electromag.etic coupling.for ultra-relativistic *** astrophysical implications of our results are discussed.

关键词： stars black holes-accretion-accretion disks-black hole physics

Enhancing.the Decomposition of Paper Cups Using.g.lleria Mellonella and Eisenia Fetida

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Journal of Renewable Materials 2024年第2期12卷 349-367页

作者： Shadi Moqbel Habib al-g.oul Abd al-Majeed al-g.zawi Rami Mukbel Civil Eng.neering.Department The University of JordanAmman11942Jordan Department of Chemistry Technical University of MunichMunichGermany Plant Production Jordan University of Science and TechnologyIrbid22110Jordan Basic Medical Veterinary Sciences Jordan University of Science and TechnologyIrbid22110Jordan

The composition of paper cups creates a challeng. for the recycling.industry,as the paperboard–plastic film composite is hard to ***,paper cups are sent to landfills or waste *** study explores the combined use of red worms(Eisenia fetida)and g.eater wax moth(g.lleria mellonella)in the biodeg.adation of paper *** study investig.tes the conditions and combinations that promote using.Eisenia fetida and g.lleria mellonella for deg.ading.paper *** study considered the influence of environmental temperature,the presence of food waste,varying.the number of Eisenia fetida worms,and the presence of a g.lleria mellonella g.owth-slowing.ag.nt on the deg.adation *** achieve the study objectives,the study followed a quantitative *** study monitored the deg.adation of paper cup cuts that were placed in jars containing.different combinations of Eisenia fetida worms,g.lleria mellonella larvae,food waste,bedding.material,and g.lleria mellonella g.owth-slowing.*** study found that the best operating.temperature is *** study found that using.food waste improves the performance of Eisenia fetida worms and g.lleria mellonella larvae *** study found that adding.a g.lleria mellonella g.owth-slowing.ag.nt slig.tly enhances the deg.adation of the paper ***,a numerical model was obtained to simulate the paper cup deg.adation efficiency.

关键词： Paper cups resource recovery recycling circular economy g.lleria mellonella Eisenia fetida

Analysis of particle dispersion and cavity formation during.bulk particle water entry using.fully coupled CFD-DEM-VOF approach

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Particuolog. 2024年第7期90卷 558-580页

作者： Utkan Çalışkan Sanja Mišković Norman B.Keevil Institute of Mining.Eng.neering University of British Columbia2329 West MallVancouverBC V6T 1Z4Canada

This paper presents the development and validation of a fully coupled computational fluid dynamics—discrete element method—volume of fluid(CFD-DEM-VOF)model to simulate the complex behavior of particle-laden flows with free *** coupling.between the fluid and particle phases is established throug. the implemented continuity,momentum,and alpha transport *** coupled particle forces such as drag.pressure g.adient,dense virtual mass,viscous,and interface forces are also integ.ated,with drag.and dense virtual mass forces being.dependent on local *** integ.ated conservative alpha transport equation ensures phase volume conservation during.interactions between particles and ***,we have implemented a trilinear interpolation method desig.ed to operate on unstructured hexahedral *** method has been tested for its ability to properly resolve the coupling.effects in the numerical simulations,particularly in cases with a relatively low cell-size *** model is validated throug. three distinct test cases:sing.e particle water entry,dam break with particles,and water entry of a g.oup of particles *** experimental setup is built to study the dynamics of the water entry of a g.oup of particles,where three key flow features are analyzed:the evolution of averag. particle velocity,cavity shape,and particle dispersion cloud profiles in *** tests involve four different scenarios,including.two different water levels(16.1 and 20.1 cm)and two different particle densities(2650 and 4000 kg.m3).Hig.-speed videometry and particle tracking.velocimetry(using.Imag.J/TrackMate)methods are employed for experimental data *** is demonstrated that numerical results are in excellent ag.eement with theoretical predictions and experimental *** study hig.lig.ts the sig.ificance of vortices in cavity shaping.and particle *** validated CFD-DEM-VOF model constitutes a robust tool for simulating.particle-laden flows,cont

关键词： CFD-DEM-VOF Trilinear interpolation Particle-laden flow Free-surface Particle water entry Volume conservation

Embryonic thermal manipulation:a potential strateg. to mitig.te heat stress in broiler chickens for sustainable poultry production

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Journal of Animal Science and Biotechnolog. 2024年第4期15卷 1347-1375页

作者： Sadid al Amaz Birendra Mishra Department of Human Nutrition Food and Animal SciencesCollege of Tropical Agriculture and Human ResourcesUniversity of Hawaii at ManoaAgSci 2161955 East‑West RdHonoluluHI 96822USA

Due to hig. environmental temperatures and climate chang., heat stress is a severe concern for poultry health and production, increasing.the propensity for food insecurity. With climate chang. causing.hig.er temperatures and erratic weather patterns in recent years, poultry are increasing.y vulnerable to this environmental stressor. To mitig.te heat stress, nutritional, g.netic, and manag.rial strateg.es have been implemented with some success. However, these strateg.es did not adequately and sustainably reduce the heat stress. Therefore, it is crucial to take proactive measures to mitig.te the effects of heat stress on poultry, ensuring.optimal production and promoting.poultry well-being. Embryonic thermal manipulation(TM) involves manipulating.the embryonic environment's temperature to enhance broilers' thermotolerance and g.owth performance. One of the most sig.ificant benefits of this approach is its cost-effectiveness and saving.time associated with traditional manag.ment practices. g.ven its numerous advantag.s, embryonic TM is a promising.strateg. for enhancing.broiler production and profitability in the poultry industry. TM increases the standard incubation temperature in the mid or late embryonic stag. to induce epig.netic thermal adaption and embryonic metabolism. Therefore, this review aims to summarize the available literature and scientific evidence of the beneficial effect of pre-hatch thermal manipulation on broiler health and performance.

关键词： Broiler Embryo Epig.netics g.obal warming Thermoreg.lation

Deep eutectic solvents:g.een multi-task ag.nts for sustainable super g.een hydrog.n technolog.es

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Journal of Energ. Chemistry 2024年第5期92卷 357-382页

作者： Raiyan al-Farsi Maan Hayyan Renewable Energ. Eng.neering.Prog.am Faculty of Engineering and TechnologyMuscat UniversityMuscat 130Oman Chemical Eng.neering.Prog.am Faculty of Engineering and TechnologyMuscat UniversityMuscat 130Oman

While reliance on renewable energ. resources has become a reality, there is still a need to deploy g.eener and more sustainable methods in order to achieve sustainable development g.als. Indeed, g.een hydrog.n is currently believed to be a reliable solution for g.obal warming.and the pollution challeng.s arising.from fossil fuels, making.it the resilient fuel of the future. However, the sustainability of g.een hydrog.n technolog.es is yet to be achieved. In this context, g.neration of g.een hydrog.n with the aid of deep eutectic solvents(DESs) as g.een mixtures has been demonstrated as a promising.research area. This systematic review article covers g.een hydrog.n g.neration throug. water splitting.and biomass fermentation when DESs are utilized within the g.neration process. It also discusses the incorporation of DESs in fuel cell technolog.es. DESs can play a variety of roles such as solvent, electrolyte, or precursor;colloidal suspension and reaction medium;g.lvanic replacement, shape-controlling. decoration, or extractive ag.nt;finally oxidant. These roles are relevant to several methods of g.een hydrog.n g.neration, including.electrocatalysis, photocatalysis, and fermentation. As such, it is of utmost importance to screen potential DES formulations and determine how they can function in and contribute throug.out the g.een hydrog.n mobility stag.s. The realization of super g.een hydrog.n g.neration stands out as a pivotal milestone in our journey towards achieving.a more sustainable form of development;DESs have g.eat potential in making.this milestone achievable. Overall, incorporating.DESs in hydrog.n g.neration constitutes a promising.research area and offers potential scalability for g.een hydrog.n production, storag.,transport, and utilization.

关键词： Watersplitting Biohydrog.n Super g.een hydrog.n Electrocatalysis Photocatalysis Fuel cell Power-to-X

Spatio-temporal coupled mode theory for nonlocal metasurfaces

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Lig.t(Science & Applications) 2024年第2期13卷 267-282页

作者： Adam Overvig.Sander A.Mann Andrea alù Photonics Initiative Advanced Science Research CenterCity University of New YorkNew YorkNY10031USA Physics Prog.am Graduate Center of the City University of New YorkNew YorkNY10016USA

Diffractive nonlocal metasurfaces have recently opened a broad rang. of exciting.developments in nanophotonics research and applications,leverag.ng.spatially extended—yet locally patterned—resonant modes to control lig.t with new deg.ees of *** conventional g.ating.responses are eleg.ntly captured by temporal coupled mode theory,current approaches are not well equipped to capture the arbitrary spatial response observed in the nascent field of nonlocal ***,we introduce spatio-temporal coupled mode theory(STCMT),capable of eleg.ntly capturing.the key features of the resonant response of wavefront-shaping.nonlocal *** framework can quantitatively g.ide nonlocal metasurface desig. while maintaining.compatibility with local metasurface frameworks,making.it a powerful tool to rationally desig. and optimize a broad class of ultrathin optical *** validate this STCMT framework ag.inst full-wave simulations of various nonlocal metasurfaces,demonstrating.that this tool offers a powerful semi-analytical framework to understand and model the physics and functionality of these devices,without the need for computationally intense full-wave *** also discuss how this model may shed physical insig.ts into nonlocal phenomena in photonics and the functionality of the resulting.*** a relevant example,we showcase STCMT’s flexibility by applying.it to study and rapidly prototype nonlocal metasurfaces that spatially shape thermal emission.

关键词： theory resonant spatially

Photometric Studies of EV Cnc and AH Cnc in the Open Cluster M67

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Research in Astronomy and Astrophysics 2024年第8期24卷 196-211页

作者： Mamatha Rani g. K.Sriram Deblina Lahiri Vijaya,A. Department of Astronomy Osmania UniversityHyderabad 500007India

Contact binaries at various stag.s of evolution unveil various operating.mechanisms that drive *** report the photometric and period variation analysis of two contact binaries EV Cnc and AH Cnc in open cluster *** observed the cluster from the JCBT 1.3 m telescope and utilized TESS and Kepler *** photometric solutions of EV Cnc and AH Cnc revealed a mass ratio of q~0.41 and~0.15 with an inclination of i=42°and87°*** solutions sug.est that EV Cnc is probably a semi-detached and AH Cnc is a deep low-mass ratio contact *** study of O-C variation analysis indicates that for both systems,the period is increasing.which sug.ests the mass transfer is occurring.from secondary to *** the case of AH Cnc and based on simulations by randomly varying.the time of minima to fit the LITE solution,we noted the third body orbital period to be around P_(3)=26.82±2.54 yr,which is different from earlier reported values and conclude that future observations are required to confirm this *** compare these two systems with other similar contact binaries to g.t an estimate of the final config.ration of the respective systems.

关键词： (stars)binaries(including.multiple) close-(stars)binaries eclipsing.stars activity

Cloud Datacenter Selection Using.Service Broker Policies:A Survey

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Computer Modeling.in Eng.neering.& Sciences 2024年第4期139卷 1-41页

作者： Salam al-E’mari Yousef Sanjalawe Ahmad al-Daraiseh Mohammad Bany Taha Mohammad aladaileh Department of Information Security Faculty of ITUniversity of PetraAmman11196Jordan Department of Cybersecurity School of ITAmerican University of Madaba(AUM)Amman11821Jordan Department of Computer Science School of ITAmerican University of Madaba(AUM)Amman11821Jordan Department of Data Science and Artificial Intellig.nce School of ITAmerican University of Madaba(AUM)Amman11821Jordan

Amid the landscape of Cloud Computing.CC),the Cloud Datacenter(DC)stands as a cong.omerate of physical servers,whose performance can be hindered by bottlenecks within the realm of proliferating.CC services.A linchpin in CC’s performance,the Cloud Service Broker(CSB),orchestrates DC *** to adroitly route user requests with suitable DCs transforms the CSB into a bottleneck,endang.ring.service *** tackle this,deploying.an efficient CSB policy becomes imperative,optimizing.DC selection to meet string.nt Qualityof-Service(QoS)*** numerous CSB policies,their implementation g.apples with challeng.s like costs and *** article undertakes a holistic review of diverse CSB policies,concurrently surveying.the predicaments confronted by current *** foremost objective is to pinpoint research g.ps and remedies to invig.rate future policy ***,it extensively clarifies various DC selection methodolog.es employed in CC,enriching.practitioners and researchers *** synthetic analysis,the article systematically assesses and compares myriad DC selection *** analytical insig.ts equip decision-makers with a prag.atic framework to discern the apt technique for their *** summation,this discourse resounding.y underscores the paramount importance of adept CSB policies in DC selection,hig.lig.ting.the imperative role of efficient CSB policies in optimizing.CC *** emphasizing.the sig.ificance of these policies and their modeling.implications,the article contributes to both the g.neral modeling.discourse and its practical applications in the CC domain.

关键词： Cloud computing cloud service broker datacenter selection quality-of-service user request

Improving.the Seg.entation of Arabic Handwriting.Using.Lig.ture Detection Technique

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Computers, Materials & Continua 2024年第5期79卷 2015-2034页

作者： Husam Ahmad al Hamad Mohammad Shehab Colleg. of Computer Sciences and Informatics Amman Arab UniversityAmman11953Jordan

Recog.izing.handwritten characters remains a critical and formidable challeng. within the realm of computervision. althoug. considerable strides have been made in enhancing.Eng.ish handwritten character recog.itionthroug. various techniques, deciphering.Arabic handwritten characters is particularly intricate. This complexityarises from the diverse array of writing.styles among.individuals, coupled with the various shapes that a sing.echaracter can take when positioned differently within document imag.s, rendering.the task more perplexing. Inthis study, a novel seg.entation method for Arabic handwritten scripts is sug.ested. This work aims to locatethe local minima of the vertical and diag.nal word imag. densities to precisely identify the seg.entation pointsbetween the cursive letters. The proposed method starts with pre-processing.the word imag. without affecting.ts main features, then calculates the directions pixel density of the word imag. by scanning.it vertically and fromang.es 30° to 90° to count the pixel density fromall directions and address the problem of overlapping.letters, whichis a commonly attitude in writing.Arabic texts by many people. Local minima and thresholds are also determinedto identify the ideal seg.entation area. The proposed technique is tested on samples obtained fromtwo datasets: Aself-curated imag. dataset and the IFN/ENIT dataset. The results demonstrate that the proposed method achievesa sig.ificant improvement in the proportions of cursive seg.entation of 92.96% on our dataset, as well as 89.37%on the IFN/ENIT dataset.

关键词： Arabic handwritten seg.entation imag. processing lig.ture detection technique intellig.nt recog.ition