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Mass predictions of the relativistic continuum Hartree-Bogoliubov model with radial basis function approach
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作者 仕敏 牛中明 梁豪兆 《中国物理C:英文版》 SCIE CAS CSCD 2019年第7期53-60,共8页
The radial basis function(RBF) approach is a powerful tool to improve nuclear mass predictions. By combining the RBF approach with the latest relativistic continuum Hartree-Bogoliubov(RCHB) model, the local systematic... The radial basis function(RBF) approach is a powerful tool to improve nuclear mass predictions. By combining the RBF approach with the latest relativistic continuum Hartree-Bogoliubov(RCHB) model, the local systematic deviations between the RCHB mass predictions and the experimental data are eliminated, and the root-meansquare(rms) mass deviation is significantly reduced from 7.923 MeV to 0.386 MeV. However, systematic deviations between the RBF improved mass predictions and the experimental data remain for nuclei with four different odd-even parities, i.e.(even Z, even N),(even Z, odd N),(odd Z, even N), and(odd Z, odd N). They can be reduced by separately training RBF for the four groups of nuclei, and the resulting rms deviation decreases to 0.229 MeV. It is found that the RBF approach can describe the deformation effects neglected in the present RCHB mass calculations, and also improves the description of the shell effect and the pairing effect. 展开更多
关键词 nuclear MASSES RADIAL basis function APPROACH RELATIVISTIC CONTINUUM Hartree-Bogoliubov MODEL
谈汉语短语、词和语素的边界问题 预览
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作者 孙妍 《成都师范学院学报》 2019年第8期93-100,共8页
原型范畴理论之下词法与句法没有明显界限,汉语也是如此。但传统的二分法无法对范畴边界部分的非典型成员做出很好的定位。因此,我们尝试在连续统观念下对词和短语的关系进行描述,提出了4个测定双音复合结构凝固性的标准,由此可描述出... 原型范畴理论之下词法与句法没有明显界限,汉语也是如此。但传统的二分法无法对范畴边界部分的非典型成员做出很好的定位。因此,我们尝试在连续统观念下对词和短语的关系进行描述,提出了4个测定双音复合结构凝固性的标准,由此可描述出典型词到典型短语之间的渐变过程。正因为复合结构本身是一个连续统,那么其构成成分——语素和词之间也不存在明显界限。在此前提下,我们进一步提出了从黏着语素到词之间的连续统。 展开更多
关键词 原型范畴 连续统 短语 语素
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城乡一体化:小城镇理论的反思与扩展 预览
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作者 李晓斐 《华南农业大学学报:社会科学版》 CSSCI 北大核心 2019年第3期131-140,共10页
费孝通先生围绕小城镇的论述,在理论层面可以分为宏观思想、中观概念与微观的具体对策三个维度,三者之间看似琐碎庞杂,其实均可被统一在工农城乡连续统的核心思想框架之下;在具体对策层面,费孝通所提出的规模经营与家庭工业这两大策略... 费孝通先生围绕小城镇的论述,在理论层面可以分为宏观思想、中观概念与微观的具体对策三个维度,三者之间看似琐碎庞杂,其实均可被统一在工农城乡连续统的核心思想框架之下;在具体对策层面,费孝通所提出的规模经营与家庭工业这两大策略在中原地区两个乡镇的具体地方实践中面临着诸多困境与挑战,尤其是人与环境两大因素对小城镇建设成败的影响。因此,新时代背景下小城镇建设的关键,首先是回归工农城乡连续统的核心思想,在此前提下,既要确保农民主体性的彰显,同时破除文化与环境二元对立观念,将小城镇视为自然环境的有机部分。城市与乡村的连续、自然与文化的一体,蕴含的是中国文明的独特智慧,致中和宇宙观为小城镇的理论拓展与实践指导提供了可能的路径与方向。 展开更多
关键词 费孝通 连续统 小城镇 主体性 宇宙观
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Nonlinear optics in the electron-hole continuum in 2D semiconductors:two-photon transition, second harmonic generation and valley current injection
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作者 Pu Gong Hongyi Yu +1 位作者 Yong Wang Wang Yao 《科学通报:英文版》 SCIE EI CSCD 2019年第15期1036-1043,共8页
We investigate two-photon transitions to the electron-hole scattering continuum in monolayer transition-metal dichalcogenides, and identify two contributions to this nonlinear optical process with opposite circularly ... We investigate two-photon transitions to the electron-hole scattering continuum in monolayer transition-metal dichalcogenides, and identify two contributions to this nonlinear optical process with opposite circularly polarized valley selection rules. In the non-interacting limit, the competition between the two contributions leads to a crossover of the selection rule with the increase of the two-photon energy. With the strong Coulomb interaction between the electron and hole, the two contributions excite electron-hole scattering states in orthogonal angular momentum channels, while the strength of the transition can be substantially enhanced by the interaction. Based on this picture of the two-photon transition, the second harmonic generation(SHG) in the electron-hole continuum is analyzed, where the Coulomb interaction is shown to greatly alter the relative strength of different cross-circular polarized SHG processes. Valley current injection by the quantum interference of one-photon and two-photon transition is also investigated in the presence of the strong Coulomb interaction, which significantly enhances the injection rate. 展开更多
关键词 2D SEMICONDUCTORS Nonlinear optics Electron-hole CONTINUUM Two-photon transition Second-harmonic generation VALLEY current injection
唐诗英译主观性动词的翻译认知识解
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作者 张艳 郭印 《西安外国语大学学报》 CSSCI 2019年第3期99-103,共5页
汉语主观性动词的一词多义以其敏感、复杂的轴心作用,既有所言之义,也有所含之义,对于意境的营造起到了独特的作用。唐诗中主观性动词在使因链上表现不同,传统的核式与线式两类解读无法对此充分解释,这给英译带来了挑战。从认知翻译视... 汉语主观性动词的一词多义以其敏感、复杂的轴心作用,既有所言之义,也有所含之义,对于意境的营造起到了独特的作用。唐诗中主观性动词在使因链上表现不同,传统的核式与线式两类解读无法对此充分解释,这给英译带来了挑战。从认知翻译视角充分考虑主观性动词的使因链表现,是避免译文中意境流失的有效途径之一。 展开更多
关键词 主观性动词 认知翻译 使因链 连续体
“把NP给VP”句研究的检讨与反思
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作者 程亚恒 《语言研究集刊》 2019年第1期47-59,333-334共14页
'把NP给VP'句是汉语中使用频率较高的一种句式。'把NP给VP'句中的VP不仅可以是动结式、动趋式,也可以是动宾式或VV、V一V、V了V等动词重叠形式,而且还可以是表状态持续的'V着',少数情况下甚至可以是有伴随成分... '把NP给VP'句是汉语中使用频率较高的一种句式。'把NP给VP'句中的VP不仅可以是动结式、动趋式,也可以是动宾式或VV、V一V、V了V等动词重叠形式,而且还可以是表状态持续的'V着',少数情况下甚至可以是有伴随成分的'一V'结构。'把NP给VP'句中的'给'是来自与事介词的'使役'标记。'把NP给VP'句包含'处置'和'致使'两个处于变化连续统中的子系统。'把NP给VP'句中,'给VP'之间也可以有多样化的状语出现。 展开更多
关键词 “把NP给VP”句 使役标记 连续统 致使 处置
Polarised radio emission associated with HESS J1912+101
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作者 Wolfgang Reich Xiao-Hui Sun 《天文和天体物理学研究:英文版》 SCIE CAS CSCD 2019年第3期123-130,共8页
The shell-type TeV source HESS J1912+101 was tentatively identified as an old supernova remnant,but is missing counterparts at radio and other frequencies.We analysed the Sino-German Urumqiλ6 cm survey and the Effels... The shell-type TeV source HESS J1912+101 was tentatively identified as an old supernova remnant,but is missing counterparts at radio and other frequencies.We analysed the Sino-German Urumqiλ6 cm survey and the Effelsberg λ11 cm and λ21 cm surveys to identify radio emission from HESS J1912+101 to clarify the question of a supernova origin.We find a partial shell of excessive polarisation at λ6 cm at the periphery of HESS J1912+101.At λ11 cm,its polarised emission is faint and suffers from depolarisation,while at λ21 cm,no related polarisation is seen.We could not separate the shell’s total intensity signal from the confusing intense diffuse emission from the inner Galactic plane.However,a high percentage of polarisation in the shell’s synchrotron emission is indicated.Our results support earlier suggestions that HESS J1912+101 is an old supernova remnant.The synchrotron emission is highly polarised,which is typical for evolved supernova remnants with low surface brightness. 展开更多
关键词 radio CONTINUUM ISM-ISM INDIVIDUAL OBJECTS HESS J1912+101-ISM magnetic FIELDS
旅游景区的类型规律 预览
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作者 邓星 王艳平 《石家庄学院学报》 2019年第6期154-159,共6页
面对日益丰富的景区类型,除了景区类型划分,类型间的逻辑关系即类型规律也成为了研究的对象.以博物馆作为实体的切入性思考对象,进而以"物性"作为总纲,给出了经济、精神与空间的景区基本型,基于连续谱思想给出了三大类景区.... 面对日益丰富的景区类型,除了景区类型划分,类型间的逻辑关系即类型规律也成为了研究的对象.以博物馆作为实体的切入性思考对象,进而以"物性"作为总纲,给出了经济、精神与空间的景区基本型,基于连续谱思想给出了三大类景区.基于耦合关系思想,给出了关于人的、文化的、时间的与生命的景区类型,从而最终给出了一个关于旅游景区类型的关系总图. 展开更多
关键词 旅游景区 类型规律 连续谱 耦合关系
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Partial Differential Equations and Continuum Mechanics:a Collection of Papers Dedicated to Professor Philippe G. Ciarlet on the Occasion of His 80th Birthday
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作者 Cristinel MARDARE Tong YANG 《应用数学学报:英文版》 SCIE CSCD 2019年第1期1-2,共2页
Preface This Special Issue in'Acta Mathematicae Applicatae Sinica(English Series)'gathers peer reviewed papers dedicated to Professor Philippe G.Ciarlet on the occasion of his eightieth birthday.Written by fri... Preface This Special Issue in'Acta Mathematicae Applicatae Sinica(English Series)'gathers peer reviewed papers dedicated to Professor Philippe G.Ciarlet on the occasion of his eightieth birthday.Written by friends and colleagues from France and Hong Kong/China,they stand as a testimony of their admiration for an exceptional human being and mathematician. 展开更多
关键词 Partial Differential Equations CONTINUUM Mechanics
语言类型学视域下的汉日复句对比研究
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作者 苏鹰 《高等日语教育》 2019年第1期139-148,159共11页
本文从单、复句认定问题及复句分类问题出发,在梳理汉日复句研究现状的同时,探讨了汉日复句的异同。汉日语言由于语言类型不同,导致了单、复句认定的不同。作为黏着语的日语,其以谓语为中心的结构(如动宾结构、主谓结构)需要经过名词化... 本文从单、复句认定问题及复句分类问题出发,在梳理汉日复句研究现状的同时,探讨了汉日复句的异同。汉日语言由于语言类型不同,导致了单、复句认定的不同。作为黏着语的日语,其以谓语为中心的结构(如动宾结构、主谓结构)需要经过名词化过程才能用于指称,进而形成复句。而汉语是孤立语,这类结构不必经过名词化就可直接用于指称,所构成的句子一般视为单句。此外,汉日语言均认定为复句的句子中也存在概念不一致(条件与因果的关系)、内涵不同(转折关系)等问题。最后,作者提出从语言类型学视角将单句—复句—语篇作为连续体,进而进行汉日复句对比研究的设想。 展开更多
关键词 复句对比研究 单复句认定 复句分类 连续体
基于BP神经网络的分段函数连续优化处理 预览 被引量:1
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作者 冯长敏 张炳江 《北京信息科技大学学报:自然科学版》 2019年第1期18-22,共5页
有些优化问题中的目标函数或者约束函数是分段函数,该类函数不具有连续性和可微性,也即不符合非线性规划问题求解的最优性条件,因而传统的梯度类算法难以求解此类优化问题。利用神经网络较强的非线性映射能力,结合最小二乘法可以进行曲... 有些优化问题中的目标函数或者约束函数是分段函数,该类函数不具有连续性和可微性,也即不符合非线性规划问题求解的最优性条件,因而传统的梯度类算法难以求解此类优化问题。利用神经网络较强的非线性映射能力,结合最小二乘法可以进行曲线拟合的特点,提出一种将分段函数处理成具有连续而且可微性的函数的方法。最后进行实例验证,并进行误差分析,结果表明该方法处理得出的连续且可微的函数对分段函数的逼近精度较高,可以利用该函数进行优化求解。 展开更多
关键词 BP神经网络 连续化 正态分布 函数逼近 最小二乘法
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Meta-optics and bound states in the continuum
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作者 Kirill Koshelev Andrey Bogdanov Yuri Kivshar 《科学通报:英文版》 SCIE EI CSCD 2019年第12期836-842,共7页
We discuss the recent advances in meta-optics and nanophotonics associated with the physics of bound states in the continuum(BICs). Such resonant states appear due to a strong coupling between leaky modes in optical g... We discuss the recent advances in meta-optics and nanophotonics associated with the physics of bound states in the continuum(BICs). Such resonant states appear due to a strong coupling between leaky modes in optical guiding structures being supported by subwavelength high-index dielectric Mieresonant nanoantennas or all-dielectric metasurfaces. First, we review briefly very recent developments in the BIC physics in application to isolated subwavelength particles. We pay a special attention to novel opportunities for nonlinear nanophotonics due to the large field enhancement inside the particle volume creating the resonant states with high-quality(high-Q) factors, the so-called quasi-BIC, that can be supported by the subwavelength particles. Second, we discuss novel applications of the BIC physics to alldielectric optical metasurfaces with broken-symmetry meta-atoms when tuning to the BIC conditions allows to enhance substantially the Q factor of the flat-optics dielectric structures. We also present the original results on nonlinear high-Q metasurfaces and predict that the frequency conversion efficiency can be boosted dramatically by smart engineering of the asymmetry parameter of dielectric metasurfaces in the vicinity of the quasi-BIC regime. 展开更多
关键词 BOUND STATES in the CONTINUUM Meta-optics Second-harmonic GENERATION Nanoresonator Metasurfaces
A robotic laparoscopic tool with enhanced capabilities and modularactuation
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作者 DAI ZhengChen WU ZhongHao +1 位作者 ZHAO JiangRan XU Kai 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第1期47-59,共13页
Due to the improved treatment outcomes, research on robotic MIS(Minimally Invasive Surgery) thrived in the past decades. A benchmark example is the da Vinci system that dominates robotic laparoscopy via its technology... Due to the improved treatment outcomes, research on robotic MIS(Minimally Invasive Surgery) thrived in the past decades. A benchmark example is the da Vinci system that dominates robotic laparoscopy via its technology excellence and strong holding of intellectual properties. This study provides an alternative approach to realize robotic laparoscopic surgeries, by presenting the development and experimentation of the SMARLT(Strengthened Modularly Actuated Robotic Laparoscopic Tool) for MIS. A dual continuum mechanism is used in the design to achieve enhanced distal dexterity, improved reliability, increased payload capability, and actuation modularity. With kinematics modelling and actuation compensation, the SMARLT can be manipulated by a generic manipulator to carry out typical laparoscopic MIS tasks, such as tissue peeling, suturing, and knot tying. Payload capability was also experimentally characterized. The SMARLT-manipulator system essentially formed a continuum-rigid hybrid structure that makes full use of the advantages from each component: the continuum mechanism as a wrist for distal dexterity and other rigid parts for position accuracy and payload capability. With the experimental demonstration of the desired functionalities, the SMARLT design can lead to promising opportunities for commercialization. 展开更多
关键词 dexterous WRIST dual CONTINUUM mechanism medical ROBOTICS MODULAR LAPAROSCOPIC tools surgical instruments
Equivalent continuum modeling of beam-like truss structures with flexible joints 预览
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作者 Fushou Liu Libin Wang +1 位作者 Dongping Jin Hao Wen 《力学学报:英文版》 SCIE EI CAS CSCD 2019年第5期1067-1078,共12页
The paper investigated the equivalent continuum modeling of beam-like repetitive truss structures considering the flexibility of joints,which models the contact between the truss member and joint by spring-damper with... The paper investigated the equivalent continuum modeling of beam-like repetitive truss structures considering the flexibility of joints,which models the contact between the truss member and joint by spring-damper with six directional stiffnesses and dampings.Firstly,a two-node hybrid joint-beam element was derived for modeling the truss member with flexible end joints,and a condensed model for the repeating element with flexible joints was obtained.Then,the energy equivalence method was adopted to equivalently model the truss structure with flexible joints and material damping as a spatial viscoelastic anisotropic beam model.Afterwards,the equations of motion for the equivalent beam model were derived and solved analytically in the frequency domain.In the numerical studies,the correctness of the presented method was verified by comparisons of the natural frequencies and frequency responses evaluated by the equivalent beam model with the results of the finite element method model. 展开更多
关键词 Large space truss structure Flexible joint Equivalent continuum modeling Anisotropic beam model Frequency response
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《现代汉语词典(第7版)》离合词讨论 预览
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作者 廖虹 《洛阳理工学院学报:社会科学版》 2019年第2期14-18,共5页
汉语中,离合词是比较特殊的一类现象,学术界普遍认为离合词合起来是词,分开是词组,但它并不等同于词或词组,而具有自身的特殊性。离合词的特殊性引起了学术界的关注和重视,学术界从分类、鉴别、原因、扩展形式、功能以及对外汉语教学等... 汉语中,离合词是比较特殊的一类现象,学术界普遍认为离合词合起来是词,分开是词组,但它并不等同于词或词组,而具有自身的特殊性。离合词的特殊性引起了学术界的关注和重视,学术界从分类、鉴别、原因、扩展形式、功能以及对外汉语教学等方面对离合词展开讨论。通过对《现代汉语词典(第7版)》中的离合词的归纳和观察,发现离合词的扩展能力有强弱之分,应将其看作一个连续统,去发现它的规律,以期更好地认识和运用。 展开更多
关键词 现代汉语 离合词 现代汉语词典 连续统
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Diffusive-stochastic-viscoelastic model on specific adhesion of viscoelastic solids via molecular bonds 预览
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作者 Kuncheng He Long Li Jizeng Wang 《力学学报:英文版》 SCIE EI CAS CSCD 2019年第2期343-354,共12页
A diffusive-stochastic-viscoelastic model is proposed for the specific adhesion of viscoelastic solids via stochastically formed molecular bonds. In this model, we assumed that molecular level behaviours, including th... A diffusive-stochastic-viscoelastic model is proposed for the specific adhesion of viscoelastic solids via stochastically formed molecular bonds. In this model, we assumed that molecular level behaviours, including the diffusion of mobile adhesion molecules and stochastic reaction between adhesion molecules and binding sites, obey the Markovian stochastic processes, while mesoscopic deformations of the viscoelastic media are governed by continuum mechanics. Through Monte Carlo simulations of this model, we systematically investigated how the competition between time scales of molecular diffusion, reaction, and deformation creep of the solids may influence the lifetime and dynamic strength of the adhesion. We revealed that there exists an optimal characteristic time of molecule diffusion corresponding to the longest lifetime and largest adhesion strength, which is in good agreement with experimental observed characteristic time scales of molecular diffusion in cell membranes. In addition, we identified that the media viscosity can significantly increase the lifetime and dynamic strength, since the deformation creep and stress relaxation can effectively reduce the concentration of interfacial stress and increases the rebinding probability of molecular bonds. 展开更多
关键词 SPECIFIC ADHESION MOLECULAR BONDS Diffusion Monte Carlo simulation CONTINUUM mechanics
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单音节形容词的名词性考察 预览
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作者 刘德贝 方绪军 《海外华文教育》 2019年第1期44-50,共7页
本文从《汉语国际教育用音节汉字词汇等级划分》(2010)中选取'白、差、长、错'等81个典型单音节形容词,考察其名词性的句法表现,认为名词性表现越多的单音节形容词在动名连续统上越靠近名词一端,单音节形容词的名词性表现反映... 本文从《汉语国际教育用音节汉字词汇等级划分》(2010)中选取'白、差、长、错'等81个典型单音节形容词,考察其名词性的句法表现,认为名词性表现越多的单音节形容词在动名连续统上越靠近名词一端,单音节形容词的名词性表现反映了形容词与名词关系的复杂性及形容词内部成员的句法差异性。 展开更多
关键词 单音节 形容词 名词性 连续统
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电力系统机电扰动传播研究综述 被引量:1
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作者 夏成军 华夏 谢家正 《电网技术》 EI CSCD 北大核心 2019年第4期1361-1370,共10页
传统基于数学模型仿真的方法难以有效解释电力系统机电动态过程的内在机理,机电波理论研究的逐步深入为此提供了新的理论工具,它从波动力学这一全新视角来分析电网中扰动的传播过程,对于揭示电力系统的机电动态机理并据此提出有效的控... 传统基于数学模型仿真的方法难以有效解释电力系统机电动态过程的内在机理,机电波理论研究的逐步深入为此提供了新的理论工具,它从波动力学这一全新视角来分析电网中扰动的传播过程,对于揭示电力系统的机电动态机理并据此提出有效的控制措施具有重要意义。论文从扰动传播模型、传播特性、机电波控制器和机电波理论的初步应用等4个方面较为系统地归纳和总结了机电波传播研究领域的方法和成果,同时提出了包括模型优化改进、特性阻抗计算、振荡机理分析、稳定控制综合应用等8个该领域亟需解决的关键问题和有待进一步研究的重点内容。 展开更多
关键词 机电波 扰动传播 连续体 离散模型 稳定控制
认知语法的“语法象征观”--认知语法理论研究之五
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作者 牛保义 牛儒雅 《中国外语》 CSSCI 北大核心 2018年第5期34-41,共8页
R. W. Langacker的认知语法最重要的思想是:语法本质上是象征性的。本文将这一思想称之为"语法的象征观"。文章第一部分介绍了"语法象征观"的内涵及特征:语法是音义结合体;语法是由图式性程度不同的模式组成的;语... R. W. Langacker的认知语法最重要的思想是:语法本质上是象征性的。本文将这一思想称之为"语法的象征观"。文章第一部分介绍了"语法象征观"的内涵及特征:语法是音义结合体;语法是由图式性程度不同的模式组成的;语法和词库是一个连续统。语法是复杂的、意象性的、整体性的、规约性的,是有理可据的。第二部分简要说明基于语法象征观的语法分析以及语法象征观的理论意义和价值,以期对认知语法理论的应用提供参照。 展开更多
关键词 认知语法 语法象征观 音义结合体 连续统 语法分析
A model of fast radio bursts: collisions between episodic magnetic blobs
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作者 Long-Biao Li Yong-Feng Huang +1 位作者 Jin-Jun Geng Bing Li 《天文和天体物理学研究:英文版》 CSCD 2018年第6期1-6,共6页
Fast radio bursts (FRBs) are bright radio pulses from the sky with millisecond durations andJansky-level flux densities. Their origins are still largely uncertain. Here we suggest a new model forFRBs. We argue that ... Fast radio bursts (FRBs) are bright radio pulses from the sky with millisecond durations andJansky-level flux densities. Their origins are still largely uncertain. Here we suggest a new model forFRBs. We argue that the collision of a white dwarf with a black hole can generate a transient accretiondisk, from which powerful episodic magnetic blobs will be launched. The collision between two consec-utive magnetic blobs can result in a catastrophic magnetic reconnection, which releases a large amountof free magnetic energy and forms a forward shock. The shock propagates through the cold magnetizedplasma within the blob in the collision region, radiating through the synchrotron maser mechanism,which is responsible for a non-repeating FRB signal. Our calculations show that the theoretical energet-ics, radiation frequency, duration timescale and event rate can be very consistent with the observationalcharacteristics of FRBs. 展开更多
关键词 ACCRETION -- ACCRETION DISKS -- MAGNETIC RECONNECTION -- radio continuum: general
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