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基于机器学习方法的短期太阳爆发活动预报模型:综述

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中国科学:地球科学 2024年

作者：黄鑫赵忠瑞钟昱丰徐龙 Marianna B.KOrSóS r.erdélyi 宁波大学信息科学与工程学院中国科学院空间天气学国家重点实验室国家空间科学中心中国科学院大学天文与空间科学学院北京元胞探索科技中心 Dipartimento di Fisica e Astronomia“Ettore Majorana” Universitàdi Catania Department of Astronomy E?tv?s Loránd University Hungarian Solar Physics Foundation Solar Physics&Space Plasma research Center (SP2rC) School of Mathematics and StatisticsUniversity of Sheffield

太阳爆发活动主要包括太阳耀斑、日冕物质抛射(coronal mass ejections, CME)和太阳质子事件(solar proton events, SPE),太阳爆发活动对空间天气和高技术领域有重要影响.太阳爆发活动短期预报是空间天气预报中一个活跃的研究领域.目前... 详细信息

太阳爆发活动主要包括太阳耀斑、日冕物质抛射(coronal mass ejections, CME)和太阳质子事件(solar proton events, SPE),太阳爆发活动对空间天气和高技术领域有重要影响.太阳爆发活动短期预报是空间天气预报中一个活跃的研究领域.目前,数值的、统计的和机器学习的方法被用来建立太阳爆发活动预报模型.随着天基和地基观测设备的发展,积累了大量的太阳观测数据,数据驱动的太阳爆发活动预报模型取得了重大进展.本文介绍了机器学习算法在太阳爆发活动预报中的应用,总结了预报建模过程,概述了太阳爆发活动预报模型的进展,并展望了未来可能的研究方向.

关键词：太阳耀斑日冕物质抛射太阳质子事件机器学习预报模型

State Transition Induced by Self-Steepening and Self Phase-Modulation

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Chinese Physics Letters 2014年第1期31卷 33-36页

作者： Jing-Song, He Shu-Wei, Xu ruderman, M. S. erdélyi, r. Department of Mathematics Ningbo University Ningbo 315211 DAMTP University of Cambridge Cambridge CB3 0WA UK School of Mathematics University of Science and Technology of China Hefei 230026 Solar Physics and Space Plasma research Centre University of Sheffield Sheffield S3 7RH UK

We present a rational solution for a mixed nonlinear Schr6dinger （MNLS） equation. This solution has two free parameters, a and b, representing the contributions of self-steepening and self phase-modulation （SPM） of an associated physical system, respectively. It describes five soliton states： a paired bright-bright soliton, a single soliton, a paired bright-grey soliton, a paired bright-black soliton, and a rogue wave state. We show that the transition among these live states is induced by self-steepening and SPM through tuning the values of a and b. This is a unique and potentially fundamentally important phenomenon in a physical system described by the MNLS eauation.

关键词： SCHrODINGEr equation SELF-phase modulation NONLINEAr optics rESEArCH SOLITONS

The potential application of red mud and soil mixture as additive to the surface layer of a landfill cover system

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Journal of Environmental Sciences 2016年第6期28卷 189-196页

作者： Eva Ujaczki Viktória Feigl Mónika Molnár Emese Vaszita Nikolett Uzinger Attila erdélyi Katalin Gruiz Department of Applied Biotechnology and Food Science Faculty of Chemical Technology and Biotechnology Budapest University of Technology and Economics H-1111 Budapest Muegyetem rkp. 3 Hungar Institute for Soil Sciences and Agricultural Chemistry Centre for Agricultural Research Hungarian Academy of Sciences H-1022 Budapest Herman Otto Street 15 Hungary A.S.A. Hungary Ltd. H-2360 Gydl Karosi Street 53 Hungary

red mud, the by-product of aluminum production, has been regarded as a problematic residue all over the world. Its storage involves risks as evidenced by the Ajka red mud spill,an accident in Hungary where the slurry broke free, flooding the surrounding areas. As an immediate remediation measure more than 5 cm thick red mud layer was removed from the flooded soil surface. The removed red mud and soil mixture（rMSM） was transferred into the reservoirs for storage. In this paper the application of rMSM is evaluated in a field study aiming at re-utilizing waste, decreasing cost of waste disposal and providing a value-added product. The purpose was to investigate the applicability of rMSM as surface layer component of landfill cover systems. The field study was carried out in two steps： in lysimeters and in field plots. The rMSM was mixed at ratios ranging between 0 and 50% w/w with low quality subsoil（LQS） originally used as surface layer of an interim landfill cover. The characteristics of the LQS ＋ rMSM mixtures compared to the subsoil（LQS） and the rMSM were determined by physical–chemical, biological and ecotoxicological methods. The addition of rMSM to the subsoil（LQS） at up to 20% did not result any ecotoxic effect, but it increased the water holding capacity. In addition, the microbial substrate utilization became about triple of subsoil（LQS） after 10 months. According to our results the rMSM mixed into subsoil（LQS） at20% w/w dose may be applied as surface layer of landfill cover systems.

关键词： red mud Soil amelioration Environmental toxicology Landfill cover constituent Field-study Lysimeter

Analysis and Optimization of Operational and Pollutant Attributes of Diesel Engine with CNT-Infused Orange Peel Biodiesel-Diesel Blend Fuel

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Journal of Thermal Science 2024年第2期33卷 761-778页

作者： ranjeet rAI r.r.SAHOO Mechanical Engineering Department GLA UniversityMathura281406India Mechanical Engineering Department IIT(BHU)Varanasi221005India

The current study is performed to find sustainable solutions for the future of transportation and environmental *** conventional methods and experimental design table(L16 Orthogonal Array)techniques have been employed to examine and optimize a diesel-powered engine's operational and pollutant *** L16 Orthogonal Array is obtained through Taguchi's experimental design approach using Minitab 16 *** experimental design incorporated three control variables,namely engine speed,fuel type,and engine load,each with four *** operational parameters,namely brake thermal efficiency(BTE)and brake specific fuel consumption(BSFC),as well as the emission characteristics,including hydrocarbon(HC),carbon monoxide(CO),nitrogen oxide(NO),and smoke emissions,were acquired using the L16 orthogonal array(OA) and subsequently *** utilization of methodologies such as signal-to-noise(S/N) ratio and grey analysis was employed to determine the optimal operational state of the engine to achieve maximum performance while minimizing *** engine's ideal state of operation,in terms of BTE and BSFC,was determined to be at 75% engine load,1000 r/min engine speed,and using 10^(-4)(in vol) carbon nanotube incorporated 20% orange peel biodiesel(OPB20CNT100) blended fuel(A3-B1-C4).The study indicated that engine load significantly influenced BTE and BSFC,with 84.05% and 87.79% contribution factors,*** 25% engine load,1000 r/min,and OPB20CNT100 fuel(A1-B1-C4) CO,smoke,NO,and HC emissions were the *** load affects emissions the *** BSFC increased 3.10% and NO emissions 1.77%.BTE,CO,smoke,and HC emissions decreased by 1.9%,12.29%,47.05%,and 47.22%,respectively,at optimal operating conditions concerning diesel *** study shows that Taguchi-Grey's experimental design optimizes diesel engine operational and pollutant *** outcomes revealed that orange peel biodiesel infused with CNT can replace diesel fuel in a

关键词： Taguchi-Grey method OPB20CNT100 transesterification S/N ratio GrG HC CO and NO

Multidimensional images and aberrations in STEM

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Chinese Physics B 2024年第9期33卷 68-74页

作者： Eric r.Hoglund Andrew r.Lupini Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831United States

recent advances in scanning transmission electron microscopy(STEM)have led to increased development of multidimensional STEM imaging modalities and novel image reconstruction *** interest arises because the main electron lens in a modern transmission electron microscope usually has a diffraction-space information limit that is significantly better than the real-space resolution of the same *** state-of-affairs is sometimes shared by other scattering methods in modern physics and contributes to a broader excitement surrounding multidimensional techniques that scan a probe while recording diffraction-space images,such as ptychography and scanning nano-beam ***,the contrasting resolution in the two spaces raises the question as to what is limiting their effective ***,we examine this paradox by considering the effects of aberrations in both image and diffraction planes,and likewise separate the contributions of pre-and post-sample *** consideration provides insight into aberration-measurement techniques and might also indicate improvements for super-resolution techniques.

关键词： scanning transmission electron microscopy (STEM) aberrations

Kinematic analysis of flexible bipedal robotic systems

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 795-818页

作者： r.FAZEL A.M.SHAFEI S.r.NEKOO Department of Mechanical Engineering Shahid Bahonar University of KermanKerman ***Iran Departamento de Ingenieria de Sistemas y Automatica Escuela Técnica Superior de IngenieriaUniversidad de SevillaSeville 41092Spain

In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous *** distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic *** is not a far-fetched assumption because in the transient(impact)phase,due to the impulsive forces which are applied to the system,the likelihood of exciting the vibration modes increases ***,the human leg bones that are involved in walking are supported by viscoelastic muscles and ***,for achieving more exact results,it is essential to model the robot links with viscoelastic *** this end,the Gibbs-Appell formulation and Newton's kinematic impact law are used to derive the most general form of the system's dynamic equations in the swing and transient phases of *** most important issue in the passive walking motion of bipedal robots is the determination of the initial robot configuration with which the system could accomplish a periodic and stable gait solely under the effect of gravitational *** extremely unstable nature of the system studied in this paper and the vibrations caused by the impulsive forces induced by the impact of robot feet with the inclined surface are some of the very serious challenges encountered for achieving the above-mentioned *** overcome such challenges,an innovative method that uses a combination of the linearized equations of motion in the swing phase and the algebraic motion equations in the transition phase is presented in this paper to obtain an eigenvalue *** solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are *** effects of the characteristic parameters of elastic links including the modulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of

关键词： bipedal robot flexible link swing phase transient phase eigenvalue problem Kelvin-Voigt coefficient

Holographic dark energy in non-conserved gravity theory

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Communications in Theoretical Physics 2024年第4期76卷 126-133页

作者： H r Fazlollahi Institute of Gravitation and Cosmology Peoples Friendship University of Russia(RUDN University)6 Miklukho-Maklaya StMoscow117198Russia

recently, reconsidering the rastall idea T_(μ;νν)^(v)=α_(,μ) through relativistic thermodynamics gives a new form for the scalar field α which led us to construct modern modified theory of gravity debugged ‘non-conserved gravity theory’ Fazlollahi 2023 Euro. Phys. J. C 83 923. This theory unlike other modified theories of gravity cannot directly explain the current acceleration expansion in the absence of the cosmological constant and or existence of other forms of dark energy. Hence, in this study we have reinvestigated holographic dark energy Ρ_(X)~H^(2) in the non-conserved theory of gravity. In this context, the density and pressure of dark energy depend on the non-conserved term and density of the dust matter field. As shown, due to non-conservation effects on large-scale structures, unlike the original holographic model, our model onsets an acceleration epoch for the current Universe satisfies observations. Moreover, the interaction and viscous scenarios are studied for this model.

关键词： non-conserved gravity covariant form of thermodynamics holographic dark energy

Investigating the impact of the universal function of the nuclear proximity potential in heavy-ion fusion cross sections

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Communications in Theoretical Physics 2024年第5期76卷 86-93页

作者： r Gharaei E Sarvari Department of Physics Sciences FacultyHakim Sabzevari UniversityPO Box 397SabzevarIran Department of Physics Faculty of ScienceFerdowsi University of MashhadPO Box 91775-1436MashhadIran Science Faculty Department of PhysicsTarbiat Modares UniversityTehranIran

The fusion barriers and cross sections of 15 colliding systems with 320≤Z_(1)Z_(2)≤1512 are investigated in detail to understand the influence of the universal function of proximity potential formalism in the heavy-ion fusion *** realize this goal,we select three versions of the phenomenological proximity potentials,including Prox.77,Zhang 2013,and Guo 2013,to calculate the nucleus-nucleus *** experimental fusion cross sections for the selected reactions are analyzed using the standard coupled-channel calculations,including couplings to the low-lying 2^(+)and 3^(-)states in the target and *** calculated results show that the universal functions of the Guo 2013 and Prox.77 models provide the lowest and highest fusion barriers,*** addition,it is found that the height of the fusion barriers is enhanced by increasing the mass number of the projectile from light to heavy *** highest sensitivity to the mass number of the projectile belongs to the results of Prox.77.A discussion is also presented on the influence of the universal function on the radial behavior of the interaction potential in the allowed region for overlapping *** results reveal that the best fit to the experimental data of the fusion cross sections for the reactions involving light and medium nuclei is obtained using the universal function of the Zhang 2013 *** the heavier systems,the results of the Guo 2013 model at sub-barrier energies provide a good description of the available data.

关键词： fusion reactions proximity-type potentials universal function coupled-channel calculations

Pile foundation in alternate layered liquefiable and non-liquefiable soil deposits subjected to earthquake loading

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 359-376页

作者： Praveen Huded M Suresh r Dash LEA Associates South East Asia Pvt.Ltd. New Delhi 110044India Indian Institute of Technology Bhubaneswar Khurda 752050India

Pile foundations are still the preferred foundation system for high-rise structures in earthquake-prone *** foundations have experienced failures in past earthquakes due to *** on pile foundations in liquefiable soils has primarily focused on the pile foundation behavior in two or three-layered soil ***,in natural occurrence,it may occur in alternative layers of liquefiable and non-liquefiable ***,the experimental and/or numerical studies on the layered effect on pile foundations have not been widely addressed in the *** of the design codes across the world do not explicitly mention the effect of sandwiched non-liquefiable soil layers on the pile *** the present study,the behavior of an end-bearing pile in layered liquefiable and non-liquefiable soil deposit is studied *** study found that the kinematic bending moment is higher and governs the design when the effect of the sandwiched non-liquefied layer is considered in the analysis as opposed to when its effect is ***,ignoring the effect of the sandwiched non-liquefied layer in a liquefiable soil deposit might be a nonconservative design approach.

关键词： pile foundation liquefaction alternately layered soil fixity effect layered effect