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Journal of Software Engineering and Applications 2013年第7期6卷 34-41页

作者： K. Mwitondi J. Bugrien K. Wang Radio and Space Services Australian Bureau of Meteorology Sheffield Hallam University Department of Computing Statistics Department Benghazi University

Detecting naturally arising structures in data is central to knowledge extraction from data. In most applications, the main challenge is in the choice of the appropriate model for exploring the data features. The choice is generally poorly understood and any tentative choice may be too restrictive. Growing volumes of data, disparate data sources and modelling techniques entail the need for model optimization via adaptability rather than comparability. We propose a novel two-stage algorithm to modelling continuous data consisting of an unsupervised stage whereby the algorithm searches through the data for optimal parameter values and a supervised stage that adapts the parameters for predictive modelling. The method is implemented on the sunspots data with inherently Gaussian distributional properties and assumed bi-modality. Optimal values separating high from lows cycles are obtained via multiple simulations. Early patterns for each recorded cycle reveal that the first 3 years provide a sufficient basis for predicting the peak. Multiple Support Vector Machine runs using repeatedly improved data parameters show that the approach yields greater accuracy and reliability than conventional approaches and provides a good basis for model selection. Model reliability is established via multiple simulations of this type.

关键词： Clustering Data Mining Density Estimation EM Algorithm sunspots Supervised Modelling Support Vector Machines Unsupervised Modelling

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The sunspots

Journal of High Energy Physics, Gravitation and Cosmology 2015年第2期1卷 72-87页

作者： Angel Fierros Palacios Instituto de Investigaciones Eléctricas División de Energías Alternas Mexico City México

In the present paper, the theoretical frame work of magneto hydrodynamics (MHD) is used to give a solution of the problem about the origin, persistence and disappearance of the sunspots;as well as their tendency to appear as bipolar magnetic couples. According to the results obtained, a possible explanation about the change of polarity in both solar hemispheres is given. Heuristic but logical arguments about the periodicity of the phenomenon of the observed magnetic polarity and the tendency of couples of sunspots to appear solely in certain latitudes that can be called tropical regions of the Sun are presented. Finally, an indirect experimental test is proposed to show the possible process that produces the polarity of the sunspots in a given cycle, as well as the invertion of that polarity in the next solar cycle.

关键词： Magnetic Field of the Spots sunspots’ Theory Magnetic Regulation of Thermal Convection Polarity of the sunspots Couples Solar Cycle Structure and Stability of the Spots Life Time of the Spots

Generalized Hierarchical Structures and Rearranging Analysis of Statistical Property of Sequence of Daily sunspots

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Generalized Hierarchical Structures and Rearranging Analysis...

The Formation and Evolution of the Sun and the Source of Star Energy as Well as the sunspots and Flares of the Sun

中国力学学会学术大会'2009

作者： Xie Yu,Zhang Mingjie,Su Weidong Stake Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Aerospace Engineering,College of Engineering, Peking University,Beijing 100871,China

The problems of sunspots have always been attractive to scientists,because they have quite important relationship to our daily *** we can manage the rules of sunspots,then we can predict the behavior of sun in short or long periods,which can serve for researching or preventing *** this article,based on the theory of hierarchical structures which is widely used in observing the scaling prop-

关键词： hierarchicalstructures sunspots EMD method randomwalking

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Journal of Physical Science and Application 2019年第2期9卷 17-25页

作者： Cuixiang Zhong Jiangxi Normal University Nanchang 330022China

Nebula theory is the most widely accepted hypothesis about the formation and evolution of the Solar System. This theoryholds that the Sun is formed from a collapsed gas cloud 4.57 billion years ago;when the core temperature of the gas cloud rises to 10million K, the thermonuclear reaction of hydrogen fusion into helium is ignited, then the Sun become a star;once the hydrogen in thecore is exhausted, the life of the star will end. But the limited hydrogen element obviously cannot satisfy such a long-termthermonuclear reaction, in order to sustain long-term thermonuclear reactions, a steady stream of fuel must be obtained from *** the existing hypothesis about the formation and evolution of the Solar System has serious defects. Thus the author has studied theformation of the Moon, the Earth and the Sun, and discovered the formation of the Sun and the real source of star energy. The authorcould also explain many solar activity phenomena such as sunspots, flares, prominences, etc.

关键词： Sun formation evolution star energy sunspots flares.

Astral Actions on Allais’ Pendulum Apparently Inexplicable by Classical Factors: A Point of the Situation

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Journal of Modern Physics 2024年第9期15卷 1375-1408页

作者： Jean-Bernard Deloly Independant Researcher Epinay sur Orge France

1) The observation by Allais of the precession of pendulums from 1954 to 1960 highlighted regularities of astral origin an in-depth analysis of which showed that, apparently, no classical phenomenon can explain them. These regularities were diurnal waves whose periods are characteristic of astral influence (the main ones being 24 h and 24 h 50 min), annual and semi-annual components, and a multi-annual component of approximately 6 years, an influence of Jupiter being a very good candidate to explain it. 2) Allais had experimentally established that all these astral influences were expressed globally on the pendulum by an action tending to call back its plane of oscillation towards a direction variable in time, and which ovalized its trajectory. In 2019 the observation of 2 pendulums in Horodnic (Romania), thanks to the use of an automatic alidade, made it possible to identify the main mechanism that, very probably, acted on the pendulum to achieve this result. This perturbation model, called “linear anisotropy”, is characterized by its “coefficient of anisotropy” η, and by the azimuth of its “direction of anisotropy”. The composition of 2 linear anisotropies is always a linear anisotropy. 3) In the search for the phenomena which could be at the origin of all what precedes, the fact that they must create an ovalization immediately eliminates some of them. 4) We have calculated the values of η corresponding to the 24 h and 24 h 50 min waves both for the observations in Horodnic and the Allais observations. The order of magnitude (some 10−7) is effectively the same in both cases. 5) Mathematically, the regularities discovered may result of a new force field but also, as Allais proposes, from the creation, under the astral influences, of a local anisotropy of the medium in which the pendulum oscillates. In the first case the length of the pendulum is involved, in the second one not. The data available do not make it possible to decide. 6) The joint exploitation, in mech

关键词： Allais Effect Pendulum Lunisolar Influence Jupiter Influence Lunar and Solar Eclipses Syzygies sunspots Solar Cycles

The Effect of Solar Activity on the Annual Precipitation in the Beijing Area

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Chinese Journal of Astronomy and Astrophysics 2004年第2期4卷 189-197页

作者： JuanZhao Yan-BenHan Zhi-AnLi DepartmentofAstronomy BeijingNormalUniversityBeijing100875 NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012

Using continuous wavelet transform, we examine the relationship between solar activity and the annual precipitation in the Beijing area. The results indicate that the annual precipitation is closely related to the variation of sunspot numbers, and that solar activity probably plays an important role in influencing the precipitation on land.

关键词： sun: activity sunspots solar-terrestrial relation

Starspots, stellar cycles and stellar flares： Lessons from solar dynamo models

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Science China(Physics,Mechanics & Astronomy) 2017年第1期60卷 1-16页

作者： Amab Rai Choudhuri Department of Physics Indian Institute of Science Bangalore 560012 India

In this review, we discuss whether the present solar dynamo models can be extrapolated to explain various aspects of stellar activity. We begin with a summary of the following kinds of data for solar-like stars:(i) data pertaining to stellar cycles from Ca H/K emission over many years;(ii) X-ray data indicating hot coronal activity;(iii) starspot data(especially about giant polar spots); and(iv) data pertaining to stellar superflares. Then we describe the current status of solar dynamo modelling—giving an introduction to the flux transport dynamo model, the currently favoured model for the solar cycle. While an extrapolation of this model to solar-like stars can explain some aspects of observational data, some other aspects of the data still remain to be theoretically explained. It is not clear right now whether we need a different kind of dynamo mechanism for stars having giant starspots or producing very strong superflares.

关键词： sunspots solar dynamo solar cycle stellar dynamo, stellar activity

Research progress based on observations of the New Vacuum Solar Telescope

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Science China(Technological Sciences) 2020年第9期63卷 1656-1674页

作者： YAN XiaoLi LIU Zhong ZHANG Jun XU Zhi Yunnan Observatories Chinese Academy of SciencesKunming 650216China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100012China Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China

The purpose of this paper is to introduce the main scientific results made by the one-meter New Vacuum Solar Telescope(NVST),which was put into commission on 2010. NVST is one of the large aperture solar telescopes in the world, located on the shore of Fuxian lake of Yunnan province in China, aiming at serving solar physicists by providing them with high resolution photospheric and chromospheric observational data. Based on the data from NVST and complementary observations from space(e.g.,Hinode, SDO and IRIS, etc), dozens of scientific papers have been published with a wide range of topics concentrating mainly on dynamics and activities of fine-scale magnetic structures and their roles in the eruptions of active-region filaments and *** achievements include dynamic characteristics of photospheric bright points, umbral dots, penumbral waves, and sunspot/light bridge oscillation, observational evidence of small-scale magnetic reconnection, and fine-scale dynamic structure of *** these new results will shed light on the better understanding of solar eruptive activities. Data release, observation proposals,and future research subjects are introduced and discussed.

关键词： sunspots solar flares solar filaments/prominences jets Ellerman bombs magnetic reconnection

On the possibility of predicting flare index and CME velocity using vector magnetograms

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Science China(Physics,Mechanics & Astronomy) 2020年第6期63卷 117-126页

作者： AnQin Chen JingXiu Wang Key Laboratory of Space Weather National Center for Space WeatherChina Meteorological AdministrationBeijing 100081China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Solar Activity of Chinese Academy of Sciences National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China

In this paper,106 active regions(ARs)in the visible solar hemisphere in solar cycle 24 whose maximum sunspot groups’areas were larger than 400μh were *** association of their flare index(Iflare),largest flare magnitude(Mflare),and fastest coronal mass ejection(CME)velocity(VCME)with the vector magnetic field parameters were examined,and attempts were made to predict Iflare,Mflare,and VCME using the vector *** and Mflare were found to have a good correlation with the total photospheric free magnetic energy density(Efree),the length of the magnetic neutral line with a steep horizontal magnetic gradient(LNL),and the area with strong magnetic shear(Aψ).Iflare and Mflare were also found to have a best correlation with ***,VCME displayed a moderate correlation with these three magnetic field parameters with a best correlation with Aψ.Thus,Efree and Aψappear to be the best parameters that can be used to predict Iflare(Mflare)and VCME,***,the multiple linear regression fit is proposed more suitable to predict Iflare and Mflare because of the stronger forecasts obtained than those by the linear fit with one magnetic field parameter for Iflare and ***,the VCME forecasts are better obtained through the linear fit with Aψ.The majority of the ARs without any CMEs never produced any flare larger than X1.0 while having a relatively lower Efree,shorter LNL,and smaller Aψ.This suggests that the larger the largest flare in an AR is,the faster the fastest CME produced by the AR will be.

关键词： sunspots magnetic field flare coronal mass ejection

Signature of the 27-day variation in hemispheric sunspot activity and asymmetry during 2010-2015

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Research in Astronomy and Astrophysics 2021年第4期21卷 331-340页

作者： Prithvi Raj Singh Ahmad Islam Saad Farid Tarun Kumar Pant Abhay Kumar Singh Department of Physics Banaras Hindu UniversityVaranasi-221005India Physics and Chemistry Department Faculty of EducationAlexandria UniversityAlexandria-21526Egypt Space Physics Laboratory VSSCThiruvananthapuram-695022India

In the present work,we study the time evolution,significance of the N-S asymmetry excesses presented as a function of the solar cycle and prominent rotational periods(~27 d)separately for the northern and southern *** have investigated short-term variations of the hemispheric solar activity(sunspot numbers and sunspot areas)during the time period 2010-2015,which covers the ascending and the maximum phase of solar cycle *** have implemented the Lomb-Scargle periodogram and continuous wavelet transform power spectrum techniques to study the time evolution and dominant rotational periods separately for the northern and southern hemispheres,and whole solar *** results showed that the northern hemisphere exhibited longer solar synodic periods than the southern hemisphere,indicating that the northern hemisphere has a lower rotation ***,the northern hemisphere was found to be dominant before transferring to the southern hemisphere during ***,the sunspot areas clearly demonstrated a two-peak structure of solar activity in the northern and southern hemispheres respectively during 2012 and *** statistical significance of the southern hemisphere affirmed enhanced excess during the maximum phase of solar cycle 24.

关键词： sunspots Sunspot Area Asymmetry Solar Cycle