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Time Dilation Cosmology 2

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Journal of Modern Ph.sics 2024年第4期15卷 448-461页

作者： Joseph.h. (Cass) Forrington Managing Editor Journal of Cosmology California USA

Th.s paper is a furth.r elaboration of th. auth.r’s Time Dilation Cosmology (TDC) h.lograph.c model th.t ties gravitation and celestial mech.nics and kinematics directly to time dilation, resolving all th. major conundrums in astroph.sics, and ties astroph.sics directly to quantum ph.sics. It begins with.a brief summary of th. TDC model and contains th. new derivation for th. time dilation version of th. formula for summing relativistic velocities, Einstein’s gravitational constant and th. time dilation versions for th. Lorentz factor and th. Euclidean norm of th. 3d velocity vector, th. two of wh.ch.can th.n be used in th. Four-velocity formula. It is demonstrated h.w orbital curvature is manifested as th. resultant of two time dilation-manifested velocities. It also explains wh. an interferometer cannot distinguish.free fall from zero gravity and furth.r elaborates on th. auth.r’s previous explanations of h.w spiral galaxies are formed, and contains math.matical proof th.t Black h.les are actually Magnetosph.ric Eternally Collapsing Objects (MECOs) th.t are massless spacetime vortices.

关键词： Gravitation Time Time Dilation Celestial Mech.nics ISM: Kinematics and Dynamics Cosmology: Th.ory Galaxies: Evolution

Extinction of Ligh. in th. Galactic h.lo: First Observational Evidence of th. Interaction of Ligh. and Dark Matter

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Journal of Modern Ph.sics 2024年第8期15卷 1144-1198页

作者： Ch.rles h. McGruder III Department of Ph.sics and Astronomy Western Kentucky University Bowling Green USA

We study th. distribution of quasars on th. celestial sph.re according to ground-based SDSS and space-based WISE and Gaia observations. All distributions as a function of galactic latitude, b, exh.bit a decrease in quasar frequency well outside th. dust in and near th. galactic plane. We prove th.t th. observed decrease in quasar frequency at h.gh.galactic latitudes is not accompanied by reddening, meaning th.t it can not be caused by dust. Th. scattering of ligh. by th. circumgalactic gas is negligible because th. Th.mson scattering cross section is very small. We conclude th. observed scattering of ligh. must be caused by dark matter in th. galactic h.lo. We determine th. mass and ch.rge of dark matter particles. If th. dark matter particle is a fermion its mass, mDMand ch.rge eDM=δe, wh.re e is th. elementary ch.rge are: mDM=3.2×10−2eV and δ=3.856×10−5. If h.wever th. dark matter particle is spinless th.n: mDM=0.511eV and δ=2.132×10−4. Th.se values for th. ch.rge of a dark matter particle are orders of magnitude h.gh.r th.n th. upper limit of th. neutrino ch.rge according to laboratory experiments. Consequently, dark matter particles are not ch.rged neutrinos. Since dark matter particles are ch.rged, th.y must emit and absorb electromagnetic radiation. h.wever, PDM~δ2, or: PDM~1.487×10−9Pe, wh.re Peis th. power output of a single electron.

关键词： Milky Way Dark Matter h.lo (1049)

Experimental validation of double-fed induction generator in oscillating water column using circulatory system-based optimization

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CLEAN ENERGY 2024年第2期8卷 127-143页

作者： Elnagh., Basem E. Ismaiel, Ah.ed M. Abdel-Kader, Fath. El Sayed Moh.mmed, Reh.m h. Abelwh.b, M. N. Suez Canal Univ Elect Power & Machine Dept Ismailia Egypt Menoufia Univ Fac Engn Elect Machine & Power Dept Menoufia Egypt Suez Canal Univ Comp & Control Dept Ismailia Egypt

Th.s paper validates th. optimal operation for a grid-connected double-fed induction generator (DFIG) in an oscillating water column power plant (OWCPP). Th.s study presents a novel optimization tech.ique called th. circulatory system-based optimization (CSBO) approach.to develop six adaptive fuzzy logic controllers (AFLCs) with.30 parameters and compare th.m to ch.otic-billiards optimization (C-BO) and genetic algorith. (GA). Th. proposed controller is also compared with.a proportional-integral differential (PID) controller based on a self-adaptive global-best h.rmony search.(SGh.). CSBO-based AFLCs are fully investigated under different scenarios and experimented with.using a real-time interface DSP1104. Th. results of using CSBO-AFLCs revealed a fast time response, fast convergence, less oversh.ot and minimal error compared with.th.se ach.eved with.C-BO-AFLC, SGh.-PID and GA-AFLC during different case studies. Th. CSBO-based AFLCs ensure maximum power from th. DFIG in an OWCPP and enh.nce dynamic response with.very low errors. Th. results sh.w th.t th. CSBO sh.ws better power tracking by 25% as compared with.C-BO, by 45% wh.n compared with.th. GA and by 56% wh.n compared with.PID. Moreover, th. integral absolute errors of six controllers are investigated to demonstrate th. feasibility of CSBO-AFLC. Th. root mean square of th. errors of six controllers using CSBO is improved by 68.27% wh.n compared with.GA, by 22.57% wh.n compared with.C-BO and by 38.42% wh.n compared with.PID. Th.se indicators demonstrate th. feasibility of CSBO wh.n compared with.oth.r algorith.s with.th. same OWCPP. Th.s paper validates th. optimal operation of a grid-connected double-fed induction generator in an oscillating water column using a novel optimization tech.ique called th. circulatory system-based optimization approach. Experiments using a real-time simulator demonstrate th. feasibility of th. approach.wh.n compared with.oth.r algorith.s. Graph.cal Abstract

关键词： circulatory system-based optimization approach adaptive fuzzy logic controller grid-tied oscillating water column power plant maximum power point tracking WAVE ENERGY-CONVERSION DESIGN OPTIMIZATION ALGORITh. CONTROller TURBINE

Th. Early Warning Signs of a Stroke: An Approach.Using Mach.ne Learning Predictions

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Journal of Computer and Communications 2024年第6期12卷 59-71页

作者： Esraa h. Augi Almabruk Sultan Department of Computer Science University of Benghazi Benghazi Libya

Early stroke prediction is vital to prevent damage. A stroke h.ppens wh.n th. blood flow to th. brain is disrupted by a clot or bleeding, resulting in brain death.or injury. h.wever, early diagnosis and treatment reduce long-term needs and lower h.alth.costs. We aim for th.s research.to be a mach.ne-learning meth.d for forecasting early warning signs of stroke. Th. meth.dology we employed feature selection tech.iques and multiple algorith.s. Utilizing th. XGboost Algorith., th. research.findings indicate th.t th.ir proposed model ach.eved an accuracy rate of 96.45%. Th.s research.sh.ws th.t mach.ne learning can effectively predict early warning signs of stroke, wh.ch.can h.lp reduce long-term treatment and reh.bilitation needs and lower h.alth.costs.

关键词： Mach.ne Learning Stroke k-Nearest Neigh.ors Decision Tree Random Forest GXboost

Scalable Jet-Based Fabrication of PEI-h.drogel Particles for CO2 Capture

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ENERGY & ENVIRONMENTAL MATERIALS 2024年第6期7卷 351-358页

作者： Jiang, Jieke van Daatselaar, Eline Wijnja, h.lke de Koning Gans, Tessa Sch.llevis, Mich.l Venner, Cornelis h. Brilman, Derk W. F. Visser, Claas Willem Univ Twente Fac Engn Technol Dept Thermal & Fluid Engn Engn Fluid Dynam Grp NL-7500 AE Enschede Netherlands Univ Twente Fac Sci & Technol Sustainable Proc Technol NL-7500 AE Enschede Netherlands

Th. capture, regeneration, and conversion of CO2 from ambient air and flue gas streams are critical aspects of mitigating global warming. Solid sorbents for CO2 absorption are very promising as th.y h.ve h.gh.mass transfer areas with.ut energy input and reduce emissions and minimize corrosion as compared to liquid sorbents. h.wever, precisely tunable solid CO2 sorbents are difficult to produce. h.re, we demonstrate th. h.gh.th.ough.ut production of h.drogel-based CO2-absorbing particles via liquid jetting. By wrapping a liquid jet consisting of an aqueous solution of cross-linkable branch.d polyeth.lenimine (PEI) with.a layer of suspension containing h.droph.bic silica nanoparticles, monodisperse droplets with.a silica nanoparticle coating layer was formed in th. air. A stable Pickering emulsion containing PEI droplets was obtained after th.se ejected droplets were collected in a h.ated oil bath. Th. droplets turn into mm-sized particles after th.rmal curing in th. bath. Th. diameter, PEI content, and silica content of th. particles were systematically varied, and th.ir CO2 absorption was measured as a function of time. Steam regeneration of th. particles enabled cyclic testing, revealing a CO2 absorption capacity of 6.5 +/- 0.5 mol kg(-1) solid PEI in pure CO2 environments and 0.7 +/- 0.3 mol kg(-1) solid PEI for direct air capture. Several th.usands of particles were produced per second at a rate of around 0.5 kg per h.ur, with.a single nozzle. Th.s process can be furth.r scaled by parallelization. Th. complete toolbox for th. design, fabrication, testing, and regeneration of functional h.drogel particles provides a powerful route toward novel solid sorbents for regenerative CO2 capture.

关键词： CO2 capture droplet h.drogel liquid jet particle steam regeneration CARBON-DIOXIDE CAPTURE STEAM REGENERATION SORBENTS ADSORPTION SILICA GAS SEPARATION RECOVERY DROPLETS METh.NE

“Yin-Yang ph.losoph.” for th. design of anticancer drug delivery nanoparticles

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Biomaterials Translational 2024年第2期5卷 144-156页

作者： Ai Y. Tian Y. Qiao J. Wang C. Li h. Sch.ol of Lifesciences Shanghai University Shanghai China

Understanding th. in vivo transport process provides guidelines for designing ideal nanoparticles (NPs) with.h.gh.r efficacy and fewer off-target effects. Many factors, such.as particle size, morph.logy, surface potential, structural stability, and etc., may influence th. delivering process of NPs due to th. existence of various ph.siological barriers with.n th. body. h.rein, we summarise th. distinct influences of NP ph.sicoch.mical properties on th. four consecutive in vivo transport steps: (1) navigating with.bloodstream with.n blood vessels, (2) transport across vasculature walls into tumour tissues, (3) intratumoural transport th.ough.th. interstitial space, and (4) cellular uptake & intracellular delivery by cancerous cells. We found th.t th. ph.losoph. beh.nd th. current consensus for NP design h.s certain similarities to th. “Yin-Yang” th.ory in traditional Ch.nese culture. Almost all ph.sicoch.mical properties, regardless of big or small sizes, long or sh.rt length. positive or negative zeta potentials, are double-edged swords. Th. balance of potential benefits and side effects, drug selectivity and accessibility sh.uld be fully considered wh.n optimising particle design, similar to th. “Yin-Yang h.rmony”. Th.s paper presents a compreh.nsive review of th. advancements in NPs research. focusing on th.ir distinct features in tumour targeting, drug delivery, and cell uptake. Additionally, it deliberates on future developmental trends and potential obstacles, th.reby aiming to uncover th. ways th.se ch.racteristics influence th. NPs’ biological activity and provide th.oretical guidance for th. targeted delivery of NPs. © 2024, Ch.nese Medical Multimedia Press Co Ltd. All righ.s reserved.

关键词： in vivo drug delivery nanoparticle design on-demand drug release targeting strategy “Yin-Yang h.rmony”

Predefined-time repetitive learning control of robotic manipulators

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Kongzh. yu Juece/Control and Decision 2024年第11期39卷 3719-3726页

作者： Li Y.-Q. Ch.n Q. Sh. h.-h. Zh.ng Z.-h. Ch.n P. College of Information Engineering Zhejiang University of Technology Hangzhou 310023 China

A backstepping-based predefined-time repetitive learning control sch.me is proposed for uncertain robot manipulators to ach.eve rapid and h.gh.precision tracking control performance. A non-singular predefined-time virtual controller is constructed to effectively avoid th. singularity issues caused by th. differentiation of th. virtual controller in conventional finite-time backstepping design. It ensures th.t th. tracking error of th. robot manipulators joint positions converges to a neigh.orh.od of th. origin with.n th. predefined time. Th.n, th. lumped uncertainty of th. manipulator is separated into periodic and non-periodic parts by considering th. periodic ch.racteristics of th. desired trajectory. A fully saturated repetitive learning law is constructed to accurately estimate and compensate for th. periodic uncertainty. Meanwh.le, a robust control law is developed and th. terminal attracting tech.ique is applied to guarantee th. effective compensation of th. non-periodic uncertainty including external disturbances, such.th.t th. h.gh.precision tracking of th. robot manipulators joint positions is ach.eved. Finally, th. stability of th. closed-loop system and th. error convergence performance of th. proposed sch.me are analyzed th.ough.th. Lyapunov stability synth.sis. Th. effectiveness of th. proposed control meth.d is verified by comparative simulations. © 2024 North.ast University. All righ.s reserved.

关键词： backstepping recursive algorith. periodic uncertainty predefined-time control repetitive learning law robot manipulator tracking control

Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied Math.matics and Mech.nics(English.Edition) 2024年第3期45卷 543-562页

作者： h.M.FEIZABAD M.h.YAS Department of Mech.nical Engineering Razi UniversityKermanshah ***Iran

Natural fibers h.ve been extensively research.d as reinforcement materials in polymers on account of th.ir environmental and economic advantages in comparison with.synth.tic fibers in th. recent *** fibers are renowned for th.ir good mech.nical properties,abundance,and sh.rt cycle *** beams are one of th. fundamental structural components and are susceptible to mech.nical loads in engineering applications,th.s paper performs a study on th. free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on th. elastic *** different functionally graded(FG)layouts and a uniform one are th. considered distributions for unidirectional long bamboo fibers across th. *** elastic properties of th. composite are determined with.th. law of *** h.milton’s principle,th. governing equations of motion are *** generalized differential quadrature meth.d(GDQM)is th.n applied to th. equations to obtain th. *** ach.eved outcomes exh.bit th.t th. natural frequency and buckling load values vary as th. fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of th. beam ***,a comparative study is conducted between th. derived analysis outcomes for BFRC and h.mogenous polymer beams to examine th. effectiveness of bamboo fibers as reinforcement materials,demonstrating th. significant enh.ncements in both.vibration and buckling responses,with.th. exception of natural frequencies for cantilever beams on th. Pasternak foundation with.th. FG-◇fiber ***,th. obtained analysis results of BFRC beams are also compared with.th.se for carbon nanotube reinforced composite(CNTRC)beams found in th. literature,indicating th.t th. buckling loads and natural frequencies of BFRC beams are lower th.n th.se of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature meth.d(GDQM)

A h.brid mach.ne-learning model for solar irradiance forecasting

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CLEAN ENERGY 2024年第1期8卷 100-110页

作者： Almarzooqi, Ameera M. Maalouf, Mah.r El-Fouly, Tarek h. M. Katzourakis, Vasileios E. El Moursi, Moh.med S. Ch.ysikopoulos, Constantinos, V Kh.lifa Univ Dept Ind & Syst Engn POB 127788 Abu Dhabi U Arab Emirates Kh.lifa Univ Abu Dh.bi Elect Engn & Comp Sci Dept Abu Dhabi U Arab Emirates Kh.lifa Univ Dept Civil Infrastruct & Environm Engn POB 127788 Abu Dhabi U Arab Emirates Tech.Univ Crete Sch Chem & Environm Engn Khania 73100 Greece

Nowcasting and forecasting solar irradiance are vital for th. optimal prediction of grid-connected solar ph.tovoltaic (PV) power plants. Th.se plants face operational ch.llenges and sch.duling dispatch.difficulties due to th. fluctuating nature of th.ir power output. As th. generation capacity with.n th. electric grid increases, accurately predicting th.s output becomes increasingly essential, especially given th. random and non-linear ch.racteristics of solar irradiance under variable weath.r conditions. Th.s study presents a novel prediction meth.d for solar irradiance, wh.ch.is directly in correlation with.PV power output, targeting both.sh.rt-term and medium-term forecast h.rizons. Our proposed h.brid framework employs a fast trainable statistical learning tech.ique based on th. truncated-regularized kernel ridge regression model. Th. proposed meth.d excels in forecasting solar irradiance, especially during h.gh.y intermittent weath.r periods. A key strength.of our model is th. incorporation of multiple h.storical weath.r parameters as inputs to generate accurate predictions of future solar irradiance values in its scalable framework. We evaluated th. performance of our model using data sets from both.cloudy and sunny days in Seattle and Medford, USA and compared it against th.ee forecasting models: persistence, modified 24-h.ur persistence and least squares. Based on th.ee widely accepted statistical performance metrics (root mean squared error, mean absolute error and coefficient of determination), our h.brid model demonstrated superior predictive accuracy in varying weath.r conditions and forecast h.rizons. A novel prediction meth.d for solar irradiance, targeting both.sh.rt-term and medium-term forecast h.rizons, is proposed to improve PV power production. Th. h.brid framework employs a fast trainable statistical learning tech.ique based on th. truncated-regularized kernel ridge regression model. Graph.cal Abstract

关键词： solar power generation kernel ridge regression h.brid model forecasting BATTERY ENERGY-STORAGE POWER PV RADIATION PREDICTION CELLS