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The Formation of Electron-capture Supernovae:A Review 认领 引用
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作者 Bo Wang Dongdong Liu +1 位作者 Yunlang Guo Zhanwen Han 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2026年第3期1-14,共14页
It is generally believed that the electron-capture reactions happen when the oxygen-neon(ONe)cores grow in masses close to the Chandrasekhar limit,leading to the formation of neutron stars(NSs)via electron-capture sup... It is generally believed that the electron-capture reactions happen when the oxygen-neon(ONe)cores grow in masses close to the Chandrasekhar limit,leading to the formation of neutron stars(NSs)via electron-capture supernovae(EC-SNe).EC-SNe are predicted to be the most likely short-lived and faint optical transients,and a small ejecta mass is expected during the collapse.This kind of SNe provide a distinct channel for producing isolated NSs and NS systems,especially for the formation of X-ray binaries and double NSs.Although EC-SNe were proposed∼45 yr ago,there are still some uncertainties for the origin of EC-SNe and their productions.In this article,we review recent studies on the two classic progenitor channels of EC-SNe,i.e.,the single star channel and the binary channel.In the single star channel,EC-SNe can happen in super asymptotic giant branch stars or He stars,whereas in the binary channel EC-SNe can occur in He stars in binaries(involving He star+MS systems and NS+He star systems)or accretion-induced collapse in white dwarf binaries(involving the singledegenerate scenario and the double-degenerate scenario).Recent progress on these two progenitor channels is discussed,including the initial parameter range for EC-SNe,the evolutionary paths to EC-SNe,related objects and some observational constraints,etc.We also make some discussions on the possible candidates for EC-SNe in this article,and the impacts of EC-SNe on some research fields,e.g.,the properties of NSs,double NS population and chemical products,etc.It is noting that EC-SNe show some similar properties with ultra-stripped SNe,e.g.,low ejecta masses and small kicks.Accordingly,we also discuss the difference between these two types of SNe in this article.Research on EC-SNe is at a pivotal stage,with key theoretical uncertainties and observational challenges requiring integrated modeling and multi-wavelength observations for robust identification. 展开更多
关键词 stars evolution-(stars:)binaries general-(stars:)binaries(including multiple) close-(stars:)supernovae general
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Formation of Extremely Low-mass White Dwarfs in Wide Orbits 认领 引用
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作者 Yangyang Zhang Zhenwei Li Xuefei Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2026年第2期218-223,共6页
Helium white dwarfs(WDs)with masses less than 0.3 M⊙are known as extremely low-mass WDs(ELM WDs),which cannot be produced by single stellar evolution in theory.Generally,these stars are believed to form through bi... Helium white dwarfs(WDs)with masses less than 0.3 M⊙are known as extremely low-mass WDs(ELM WDs),which cannot be produced by single stellar evolution in theory.Generally,these stars are believed to form through binary interactions.Recently,two ELM WDs in unusually wide orbits were reported,i.e.,KIC 8145411 and HE0430-2457.Their orbital separations are too wide to be produced by the binary evolution scenario.In this work,we study the formation of wide-orbit ELM WD binaries from hierarchical triple systems.In this scenario,an ELM WD is formed from the inner binary and subsequently forms a wide binary system with the third object.We find that the merger of an evolved star with a brown dwarf in the inner binary fails to produce single ELM WDs,but Type Ia supernovae(SNe Ia)explosions can successfully do so.Furthermore,we investigate the impact of the supernova explosion on the orbital distribution of the surviving binary and find that this channel may have a probability of reproducing the orbital parameters of HE 0430-2457,but fails to reproduce the observed features of KIC 8145411.This supports recent observational recalibrations suggesting that KIC 8145411 resides in a triple system rather than a binary. 展开更多
关键词 (stars)binaries(including multiple) close-stars evolution-(stars) white dwarfs
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Expected Evolution of the Binary System ATLAS J1138-5139 认领 引用
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作者 Jing-Qi Chen Hai-Liang Chen +2 位作者 Zheng-Wei Liu Xuefei Chen Zhanwen Han 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2026年第5期156-162,共7页
ATLAS J1138-5139 is a newly detected ultra-compact double white dwarf(DWD) system which is composed of a 1.02 M⊙ carbon-oxygen white dwarf(CO WD) and a 0.24M⊙ helium(He) WD with an orbital period of about 27.68 minu... ATLAS J1138-5139 is a newly detected ultra-compact double white dwarf(DWD) system which is composed of a 1.02 M⊙ carbon-oxygen white dwarf(CO WD) and a 0.24M⊙ helium(He) WD with an orbital period of about 27.68 minutes,making it one of the shortest-period DWD systems known.The future evolution and final fate of this system remain unexplored.In this work,we investigate the evolution of ATLAS J1138-5139 with the onedimensional stellar evolution code Modules for Experiments in Stellar Astrophysics.We find that ATLAS J1138-5139 will evolve into an AM Canum Venaticorum system in about~6.3 Myr.Afterwards,the transferred material from the He WD companion start to build up to form a He shell near the surface of the CO WD.This accumulated He-shell masses can be up to approximately 0.12M⊙,which is likely to trigger a double-detonation(DDet) explosion of the CO WD.We therefore expect that ATLAS J1138-5139 will likely explode as a type Ⅰa supernova eventually through the DDet explosion mechanism.Moreover,our calculations show that ATLAS J1138-5139 will be a promising target for gravitational-wave detection by future detectors like LISA,TianQin and Taiji. 展开更多
关键词 methods numerical-(stars:)binaries(including multiple) close-stars evolution-(stars:)supernovae general-(stars:)white dwarfs
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论《商君书》的历史观——基于历史唯物主义的视角 认领 引用
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作者 王永力 《西部学刊》 2026年第13期142-145,共4页
关于《商君书》的历史观,一直存在“进化论”和“变易论”之争,症结一方面在于如何对待《商君书》中描述的历史知识,另一方面在于如何看待整个人类历史的变化趋势。基于历史唯物主义的视角透视《商君书》可知,它的历史观是一种主体错位... 关于《商君书》的历史观,一直存在“进化论”和“变易论”之争,症结一方面在于如何对待《商君书》中描述的历史知识,另一方面在于如何看待整个人类历史的变化趋势。基于历史唯物主义的视角透视《商君书》可知,它的历史观是一种主体错位的历史唯物主义,主要体现在三个方面:《商君书》高度肯定社会存在对社会意识的决定性作用;《商君书》清晰地认识到社会意识对社会存在具有能动反作用;《商君书》坚定秉持“圣人创造历史”说。 展开更多
关键词 “进化论” “变易论” 历史唯物主义 主体错位
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演化的媒介:莱姆《技术大全》与1964年媒介理论的另一条线索 认领 引用
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作者 韩晓强 《山东科技大学学报（社会科学版）》 2026年第3期12-27,共16页
虚拟现实及生成式人工智能技术的发展,强化了技术的本体论地位,也激发了一种基于技术思辨/推演的未来意识。这种未来意识让我们有必要必须追溯技术哲学的历史线索,在历史的谱系中,波兰作家斯坦尼斯瓦夫·莱姆的《技术大全》处在一... 虚拟现实及生成式人工智能技术的发展,强化了技术的本体论地位,也激发了一种基于技术思辨/推演的未来意识。这种未来意识让我们有必要必须追溯技术哲学的历史线索,在历史的谱系中,波兰作家斯坦尼斯瓦夫·莱姆的《技术大全》处在一个奇特的位置,它既是1964年媒介理论元年的核心文献之一,也因语言壁垒和科幻作家的身份长期游离于学术谱系之外。然而,《技术大全》提供了媒介理论研究的另一条线索,即媒介演化论的线索,这不但与麦克卢汉、古昂、西蒙东等人同期的思想产生了理论共鸣,也对后续学界的媒介研究产生了潜移默化的影响。重新探索莱姆的哲学框架及其对当下技术问题的延展和贡献,有助于重建当下的媒介理论坐标,也有助于探索莱姆自身写作实践中的技术-艺术互动关系。 展开更多
关键词 莱姆 《技术大全》 比较演化论 技术哲学 媒介理论
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进化论思想与近代小说观念的变迁 认领 引用
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作者 汪胜 《江苏海洋大学学报（人文社会科学版）》 2026年第4期66-76,共11页
进化论思想在近代中国传播广泛、影响深远,推动了社会各领域的发展。在其影响下,人们开始用进化观念审视小说的变迁,有意识地探讨中国小说史。面对社会和文学的进化,人们不再局限于传统的经史观,而是将小说抬升至“文学之最上乘”的地位... 进化论思想在近代中国传播广泛、影响深远,推动了社会各领域的发展。在其影响下,人们开始用进化观念审视小说的变迁,有意识地探讨中国小说史。面对社会和文学的进化,人们不再局限于传统的经史观,而是将小说抬升至“文学之最上乘”的地位,寄希望于小说的社会功用,以开启民智,改良社会。因此,这一时期的小说创作出现了改良和求新的呼声,新小说受到广泛的推崇,旧小说不可避免地遭到否定和批判,展现了中国小说由古典向现代的过渡。进化论思想虽然由于固有的缺陷和片面的解读产生了一系列的理论弊端,但毫无疑问对近代小说观念的变迁作出了重要贡献。 展开更多
关键词 进化论 近代 小说观念 新小说
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The FAST Galactic Plane Pulsar Snapshot Survey. Ⅶ. Six Millisecond Pulsars in Compact Orbits with Massive White Dwarf Companions 认领 引用
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作者 Z.L.Yang J.L.Han +12 位作者 T.Wang P.F.Wang W.Q.Su W.C.Chen C.Wang D.J.Zhou Y.Yan W.C.Jing N.N.Cai L.Xie J.Xu H.G.Wang R.X.Xu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2025年第1期64-74,共11页
Binary millisecond pulsars with a massive white dwarf(WD)companion are intermediate-mass binary pulsars(IMBPs).They are formed via the Case BB Roche-lobe overflow evolution channel if they are in compact orbits with a... Binary millisecond pulsars with a massive white dwarf(WD)companion are intermediate-mass binary pulsars(IMBPs).They are formed via the Case BB Roche-lobe overflow evolution channel if they are in compact orbits with an orbital period of less than 1 day.They are fairly rare in the known pulsar population;only five such IMBPs have been discovered before,and one of them is in a globular cluster.Here we report six IMBPs in compact orbits:PSRs J0416+5201,J0520+3722,J1919+1341,J1943+2210,J1947+2304 and J2023+2853,discovered during the Galactic Plane Pulsar Snapshot survey by using the Five-hundred-meter Aperture Spherical radio Telescope,doubling the number of such IMBPs due to the high survey sensitivity in the short survey time of 5 minutes.Follow-up timing observations show that they all have either a CO WD or an ONeMg WD companion with a mass greater than about 0.8M⊙in a very circular orbit with an eccentricity in the order of10−5.PSR J0416+5201 should be an ONeMg WD companion with a remarkable minimum mass of 1.28M⊙.These massive WD companions lead to a detectable Shapiro delay for PSRs J0416+5201,J0520+3722,J1943+2210,and J2023+2853,indicating that their orbits are highly inclined.From the measurement of the Shapiro delay,the pulsar mass of J1943+2210 was constrained to be 1.84+0.11-0.09M⊙,and that of PSR J2023+2853 to be 1.28+0.06-0.05M⊙. 展开更多
关键词 (stars:)binaries(including multiple) close-stars evolution-(stars:)pulsars general
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Producing Type Ia Supernovae from Hybrid CONe White Dwarfs with Mainsequence Binary Companions at Low Metallicity of Z=0.0001 认领 引用
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作者 Boyang Guo Xiangcun Meng +2 位作者 Zhijia Tian Jingxiao Luo Zhengwei Liu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2025年第1期344-356,共13页
The nature of progenitors of Type Ia supernovae(SNe Ia)and their explosion mechanism remains unclear.It has been suggested that SNe Ia may have resulted from thermonuclear explosions of hybrid carbon-oxygen-neon white... The nature of progenitors of Type Ia supernovae(SNe Ia)and their explosion mechanism remains unclear.It has been suggested that SNe Ia may have resulted from thermonuclear explosions of hybrid carbon-oxygen-neon white dwarfs(CONe WDs)when they grow in mass to approach the Chandrasekhar mass limit by accreting matter from a binary main-sequence(MS)companion.In this work,we combine the results of detailed binary evolution calculations with population synthesis models to investigate the rates and delay times of SNe Ia in the CONe WD+MS channel at a low metallicity environment of Z=0.0001.For a constant star formation rate of 5M⊙yr−1,our calculations predict that the SN Ia rates in the CONe WD+MS channel at low metallicity of Z=0.0001 is about 0.11−3.89×10−4 yr−1.In addition,delay times in this channel cover a wide range of 0.05−2.5 Gyr.We further compare our results to those given by a previous study for the CONe WD+MS channel with a higher metallicity of Z=0.02 to explore the influence of metallicity on the results.We find that these two metallicity environments give a slight difference in rates and delay times of SNe Ia from the CONe WD+MS channel,although SNe Ia produced at a low metallicity environment of Z=0.0001 have relatively longer delay times. 展开更多
关键词 methods numerical-(stars:)binaries(including multiple) close-stars evolution-(stars:)supernovae general-(stars:)white dwarfs
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A Helium Nova[HP99]159:Past,Present and Future 认领 引用
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作者 Xin-Jie Luo Dong-Dong Liu Bo Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2025年第9期148-153,共6页
Type Ia supernovae(SNe Ia)are among the most extreme phenomena in the Universe and play a crucial role in the studies of stellar evolution,galactic chemical evolution and cosmology.However,the progenitors of SNe Ia ar... Type Ia supernovae(SNe Ia)are among the most extreme phenomena in the Universe and play a crucial role in the studies of stellar evolution,galactic chemical evolution and cosmology.However,the progenitors of SNe Ia are still under debate.It has been suggested that SNe Ia could be produced by helium(He)novae in the singledegenerate channel.Recently,a He nova named[HP99]159 was proposed to be a progenitor candidate for SNe Ia,in which the white dwarf(WD)has a mass of 1.20.4+0.18M⊙,the He star’s mass ranges from 0.8M⊙to 2.0M⊙and the orbital period was suggested to be 2.33 or 1.16 days.In the present work,we evolved a large number of primordial binaries to the formation of WD+He star systems and investigated their future evolution.We provided a representative evolutionary track of[HP99]159 and found that[HP99]159 may originate from a primordial binary with a 6.16M⊙primary and a 4.32M⊙secondary with an initial orbital period of 5110 days.We also found that[HP99]159 might evolve to an SN Ia explosion as suggested by previous studies,or it may also form an accretion-induced collapse event or a wide double WD.Further detailed observations are needed in future studies to provide more information about the precise nature of[HP99]159. 展开更多
关键词 (stars:)binaries(including multiple) close-stars individual([HP99]159)-stars evolution-(stars:)supernovae general-(stars:)white dwarfs
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演化论视角下中国乡村多维韧性的时空格局及交互机制 认领 引用 被引量：2
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作者 吴宝锐 苏飞 施嘉璐 《地理与地理信息科学》 CSCD 北大核心 2025年第6期81-89,共9页
乡村韧性发展是实现脱贫攻坚与乡村振兴有效衔接的关键路径与重要举措。该文基于演化论视角,运用纵横向拉开档次法与地理探测器等方法探究2011—2022年中国省域乡村多维韧性的时空格局与交互机制。结果表明:①全球化语境下的乡村韧性建... 乡村韧性发展是实现脱贫攻坚与乡村振兴有效衔接的关键路径与重要举措。该文基于演化论视角,运用纵横向拉开档次法与地理探测器等方法探究2011—2022年中国省域乡村多维韧性的时空格局与交互机制。结果表明:①全球化语境下的乡村韧性建构需要突破封闭系统认知,关注“区域内部”跨尺度关联与“扰动源”跨尺度冲击,并聚焦韧性系统内部的协同适应机制;②研究期内中国乡村多维(经济、社会、生态)韧性水平均呈上升趋势,区域差异缩小,提升乡村生态韧性是我国部分地区摆脱韧性发展“困境”的关键路径;③乡村多维韧性的交互作用类型均为双因素增强,表明子系统间的协同作用对于整体系统稳定以及韧性发展能力提升具有重要意义。最后,依据乡村多维韧性的跨尺度关联与多系统联动特征为政策体系完善提供了针对性建议。 展开更多
关键词 乡村韧性 全球化 演化论 跨尺度 交互机制
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辩证进化:世界语与《新青年》的分野 认领 引用
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作者 韩琛 《东方论坛—青岛大学学报（社会科学版）》 2025年第5期92-107,共16页
民国初年,围绕世界语及相关思想问题,中国知识者在《新青年》上展开论战。有意味的是,无论支持还是反对世界语,论战各方皆以进化论为依据,并展现关于进化论的三种本土化阐释:革命进化论、俱分进化论和历史进化论,吴稚晖、章太炎和胡适... 民国初年,围绕世界语及相关思想问题,中国知识者在《新青年》上展开论战。有意味的是,无论支持还是反对世界语,论战各方皆以进化论为依据,并展现关于进化论的三种本土化阐释:革命进化论、俱分进化论和历史进化论,吴稚晖、章太炎和胡适则是三种观念的各自代表。自严复译介进化论之后,其在中国的现代化进程中一直举足轻重,既被视为规定人类社会发展的必然法则,亦激化欧化与国粹、公理与伦理的冲突,而围绕进化论形成的不同创造性诠释,则凸显中国知识者在过渡时代的思想共识与分野。对进化论的普遍接受体现出中国知识者的科学理性共识,而对进化论的不同阐述则曝露了思想模式上的一元论与多元论、建构理性与批判理性的分歧,前者对后者的压抑规约了日后中国的历史走向。 展开更多
关键词 《新青年》 世界语 革命进化论 俱分进化论 历史进化论
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《诗经·小宛》“螟蛉有子”句章释郑笺发微 认领 引用
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作者 付兮垚 刁涵 《西南交通大学学报（社会科学版）》 2025年第3期122-132,共11页
作为章太炎的代表作,《訄书》反映了章太炎中西融合的学术思想,其中对郑玄有关《诗经》“螟蛉有子”句笺注的理解与阐释便充分体现了这一特点。在《訄书》中,章太炎肯定了郑玄对《诗经》“螟蛉有子”句“有万民不能治,则能治者将得之”... 作为章太炎的代表作,《訄书》反映了章太炎中西融合的学术思想,其中对郑玄有关《诗经》“螟蛉有子”句笺注的理解与阐释便充分体现了这一特点。在《訄书》中,章太炎肯定了郑玄对《诗经》“螟蛉有子”句“有万民不能治,则能治者将得之”的阐释,并以此比附中国同西方的竞争关系,从生物种族的视角赋予了这一解释以新的内涵。章氏这一解读表明其在基于古文经学立场的同时,又吸收接纳了西方进化论的学说观点。章太炎“中西融合”的学术思想也折射出近代中国学术既传承又趋新的复杂面向。 展开更多
关键词 章太炎 《訄书》 古文经学 进化论
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Distributions of Neutron Exposures in AGB Stars and the Galaxy 认领 引用 被引量：3
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作者 Wen-Yuan Cui Feng-Hua Zhang +2 位作者 Wei-Juan Zhang Lu Zhang Bo Zhang 《Chinese Journal of Astronomy and Astrophysics》 2007年第2期224-234,共11页
Based on the s-process nucleosynthesis model with the 13C（α, n）16O reaction occurring under radiative conditions in the interpulse phases, we investigate the characteristics of the distribution of neutron exposure ... Based on the s-process nucleosynthesis model with the 13C（α, n）16O reaction occurring under radiative conditions in the interpulse phases, we investigate the characteristics of the distribution of neutron exposure in low-mass Asymptotic Giant Branch （AGB） stars. We introduce a new concept, the distribution of neutron exposures of the Galaxy （NEG）, to study the chemical evolution characteristics of the Galaxy for s-process elements. Using a chemical evolution model of the Galaxy, we develop a model for the NEG and obtain the evolution results of the NEG in different epochs. The present results appear to reasonably reproduce the distribution of neutron exposures of the solar system （hereafter NES）. The main component and the strong component in the NES are built up in different epochs. The strong component of the s-process is mainly synthesised in the low-mass and metal-poor AGB stars, and the main component is produced by the s-process in the low-mass AGB stars with higher metallicities. 展开更多
关键词 Galaxy evolution- stars AGB and post-AGB- stars abundances
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The star formation history of redshift z^2 galaxies:the role of the infrared prior 认领 引用
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作者 Lu-Lu Fan Andrea Lapi +3 位作者 Alessandro Bressan Mario Nonino Gianfranco De Zotti Luigi Danese 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第1期15-34,共20页
We build a sample of 298 spectroscopically-confirmed galaxies at redshift z - 2, selected in the z850-band from the GOODS-MUSIC catalog. By utilizing the rest frame 8 p.m luminosity as a proxy of the star formation ra... We build a sample of 298 spectroscopically-confirmed galaxies at redshift z - 2, selected in the z850-band from the GOODS-MUSIC catalog. By utilizing the rest frame 8 p.m luminosity as a proxy of the star formation rate （SFR）, we check the accuracy of the standard SED-fitting technique, finding it is not accurate enough to provide reliable estimates of the physical parameters of galaxies. We then develop a new SED-fitting method that includes the IR luminosity as a prior and a generalized Calzetti law with a variable Rv. Then we exploit the new method to re-analyze our galaxy sample, and to robustly determine SFRs, stellar masses and ages. We find that there is a general trend of increasing attenuation with the SFR. Moreover, we find that the SFRs range between a few to 103 M~ yr-1, the masses from 109 to 4 ~ 1011 Mo, and the ages from a few tens of Myr to more than 1 Gyr. We discuss how individual age measurements of highly attenuated objects indicate that dust must have formed within a few tens of Myr and already been copious at 〈 100 Myr. In addition, we find that low luminosity galaxies harbor, on average, significantly older stellar populations and are also less massive than brighter ones; we discuss how these findings and the well known ＇downsizing＇ scenario are consistent in a framework where less massive galaxies form first, but their star formation lasts longer. Finally, we find that the near-IR attenuation is not scarce for luminous objects, contrary to what is customarily assumed; we discuss how this affects the interpretation of the observed M,/L ratios. 展开更多
关键词 cosmology： observations- galaxies： evolution- galaxies： high redshift-- galaxies： stellar content -- dust extinction
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The effects of convective overshooting on naked helium stars 认领 引用 被引量：1
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作者 Jing-Zhi Yan Chun-Hua Zhu +1 位作者 Zhao-Jun Wang Guo-Liang Lü 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第9期75-82,共8页
Using stellar evolutionary models, we investigate the effects of convective overshooting on naked helium stars. We find that a larger value of overshooting parameter δov results in a larger convective core, which pro... Using stellar evolutionary models, we investigate the effects of convective overshooting on naked helium stars. We find that a larger value of overshooting parameter δov results in a larger convective core, which prolongs the lifetimes of naked helium stars on the helium main sequence and leads to higher effective temperatures and luminosities. For naked helium stars with masses lower than about 0.8 Mo, they hardly become giant stars as a result of a weak burning shell. However, naked helium stars with masses between about 0.8 M⊙ and 1.1 M⊙ can evolve into giant branch phases, and finally become carbon oxygen white dwarfs. 展开更多
关键词 stars evolution- stars interiors- stars fundamental parameters
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Long-term Evolution of Solar Activity and Prediction of the Following Solar Cycles 认领 引用 被引量：2
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作者 Pei-Xin Luo Bao-Lin Tan 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期194-204,共11页
Solar activities have a great impact on modern high-tech systems,such as human aerospace activities,satellite communication and navigation,deep space exploration,and related scientific research.Therefore,studying the ... Solar activities have a great impact on modern high-tech systems,such as human aerospace activities,satellite communication and navigation,deep space exploration,and related scientific research.Therefore,studying the long-term evolution trend of solar activity and accurately predicting the future solar cycles are highly anticipated.Based on the wavelet transform and empirical function fitting of the longest recorded data of the annual average relative sunspot number(ASN)series of 323 yr to date,this work decisively verifies the existence of the solar century cycles and confirms that its length is about 104.0 yr,and the magnitude has a slightly increasing trend on the timescale of several hundred years.Based on this long-term evolutionary trend,we predict solar cycles 25 and26 by using phase similar prediction methods.As for solar cycle 25,its maximum ASN will be about146.7±33.40,obviously stronger than solar cycle 24.The peak year will occur approximately in 2024,and the period will be about 11±1 yr.As for solar cycle 26,it will start around 2030,and reach its maximum between2035 and 2036,with maximum ASN of about 133.0±3.200,and period of about 10 yr. 展开更多
关键词 Sun activity-Sun evolution-(Sun) sunspots-methods data analysis
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Chemical Evolution During the Formation of Molecular Clouds 认领 引用 被引量：1
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作者 Jingfei Sun Fujun Du 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第6期269-290,共22页
To study the chemical evolution during the formation of molecular clouds,we model three types of clouds with different density structures:collapsing spherical,collapsing ellipsoidal,and static spherical profiles.The c... To study the chemical evolution during the formation of molecular clouds,we model three types of clouds with different density structures:collapsing spherical,collapsing ellipsoidal,and static spherical profiles.The collapsing models are better than the static models in matching the observational characteristics in typical molecular clouds.This is mainly because the gravity can speed up the formation of some important molecules(e.g.,H2,CO,OH)by increasing the number density during collapse.The different morphologies of prolate,oblate,and spherical clouds lead to differences in chemical evolution,which are mainly due to their different evolution of number density.We also study the effect of initial chemical compositions on chemical evolution,and find that H atoms can accelerate OH formation by two major reactions:O+H→OH in gas phase and on dust grain surfaces,leading to the models in which hydrogen is mainly atomic initially better match observations than the models in which hydrogen is mainly molecular initially.Namely,to match observations,initially hydrogen must be mostly atomic.The CO molecules are able to form even without the pre-existence of H2.We also study the influence of gas temperature,dust temperature,intensity of interstellar radiation field and cosmic-ray ionization rate on chemical evolution in static clouds.The static CO clouds with high dust temperature,strong radiation field,and intensive cosmic rays are transient due to rapid CO destruction. 展开更多
关键词 ISM abundances-(ISM:)evolution-ISM molecules
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基于改进型进化机制的萤火虫优化算法 认领 引用 被引量：13
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作者 符强 童楠 +1 位作者 钟才明 赵一鸣 《计算机科学》 CSCD 北大核心 2014年第3期228-231,248,共4页
分析了萤火虫算法的进化计算机制,并利用实例对萤火虫算法中容易发生进化过早停滞的原因进行了研究。提出了一种基于新型进化计算模式的改进型萤火虫优化算法,该算法在进化初期利用种群最优萤火虫激发群中其他个体的寻优能力,在萤火虫... 分析了萤火虫算法的进化计算机制,并利用实例对萤火虫算法中容易发生进化过早停滞的原因进行了研究。提出了一种基于新型进化计算模式的改进型萤火虫优化算法,该算法在进化初期利用种群最优萤火虫激发群中其他个体的寻优能力,在萤火虫相互之间建构了有效的信息交互网络后,各萤火虫将借助各自视觉范围内的更优近邻个体完成后期搜索和进化,当种群陷入局部最优区域时,利用高斯变异改善萤火虫个体的多样性。利用标准测试函数进行了实验分析,结果表明,改进后的萤火虫算法能有效改善过早进化停滞问题。 展开更多
关键词 萤火虫算法 群智能 进化机制 高斯变异
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大规模演化知识网络中的关联推理 认领 引用 被引量：6
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作者 赵泽亚 贾岩涛 +2 位作者 王元卓 靳小龙 程学旗 《计算机研究与发展》 EI CSCD 北大核心 2016年第2期492-502,共11页
网络大数据时代的到来使得知识网络中时空信息越来越丰富.现有的知识网络描述模型对知识的时空信息刻画不足.研究证明,利用网络中知识的时空信息以及相关性,能够提高网络中知识间的关联推理的准确率.针对以上问题,首先提出了一种包含时... 网络大数据时代的到来使得知识网络中时空信息越来越丰富.现有的知识网络描述模型对知识的时空信息刻画不足.研究证明,利用网络中知识的时空信息以及相关性,能够提高网络中知识间的关联推理的准确率.针对以上问题,首先提出了一种包含时空信息的演化知识网络表示模型,然后研究在该网络模型上的关联推理问题,提出了一种基于背包问题的知识间关联推理方法.在多个数据集上的实验证明了所提出的关联推理方法的有效性以及对大规模知识网络的适应性. 展开更多
关键词 关联推理 演化知识网络 背包问题 链接延展模式 知识库
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自然选择理论在行为研究中的核心概念辨析 认领 引用 被引量：7
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作者 蒋柯 熊哲宏 胡喻 《自然辩证法研究》 CSSCI 北大核心 2009年第5期16-20,共5页
关于自然选择理论在行为研究中的意义,存在着三种主要的误解,分别是:第一,人的行为是遗传决定的;第二,如果行为是进化而来的,那我们就无法改变它;第三,当前的机制是最佳设计。这些误解对于自然选择理论的运用和发展不利。本文通过分析指... 关于自然选择理论在行为研究中的意义,存在着三种主要的误解,分别是:第一,人的行为是遗传决定的;第二,如果行为是进化而来的,那我们就无法改变它;第三,当前的机制是最佳设计。这些误解对于自然选择理论的运用和发展不利。本文通过分析指出:这些误解实际上起源于对进化理论的决定论和目的论误读,而引起决定论和目的论误读的关键是关于自然选择核心概念理解的分歧。本文从对决定论和目的论误读的分析入手,对自然选择理论的几个核心概念进行辨析。 展开更多
关键词 进化论 进化心理学 决定论 目的论 自然选择
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