期刊文献+
共找到18篇文章
< 1 >
每页显示 20 50 100
“各各”、“各个”和“个个”——基于语料库的比较研究 被引量:2
1
作者 倪涛 《长治学院学报》 2012年第6期62-64,共3页
研究以"当代汉语小说语料库"和"汉语复句语料库"为语料来源,对汉语中三个同音词——"各各"、"各个"和"个个"进行了定量考察,并借助搜集的语料比较了三个词语的异同,总结了其各自的... 研究以"当代汉语小说语料库"和"汉语复句语料库"为语料来源,对汉语中三个同音词——"各各"、"各个"和"个个"进行了定量考察,并借助搜集的语料比较了三个词语的异同,总结了其各自的特点。 展开更多
关键词 “各各” “各个” “个个” 语料库
下载PDF
Anisotropy measurements and characterization of the Qingshankou shale
2
作者 Li Qing-feng Yan Xue-hong +5 位作者 Yan Wei-lin Ren Li Wang Peng Han Jian-qiang Xia Xue Chen Hao 《Applied Geophysics》 SCIE CSCD 2024年第3期468-478,617,共12页
Qingshankou shale(Gulong area,China)exhibits strong acoustic anisotropy characteristics,posing significant challenges to its exploration and development.In this study,the five full elastic constants and multipole resp... Qingshankou shale(Gulong area,China)exhibits strong acoustic anisotropy characteristics,posing significant challenges to its exploration and development.In this study,the five full elastic constants and multipole response law of the Qingshankou shale were studied using experimental measurements.Analyses show that the anisotropy parametersϵandγin the study region are greater than 0.4,whereas the anisotropy parameterδis smaller,generally 0.1.Numerical simulations show that the longitudinal and transverse wave velocities of these strong anisotropic rocks vary significantly with inclination angle,and significant differences in group velocity and phase velocity are also present.Acoustic logging measures the group velocity in dipped boreholes;this differs from the phase velocity to some extent.As the dip angle increases,the longitudinal and SH wave velocities increase accordingly,while the qSV-wave velocity initially increases and then decreases,reaching its maximum value at a dip of approximately 40°.These results provide an effective guide for the correction and modeling of acoustic logging time differences in the region. 展开更多
关键词 Transverse isotropy anisotropy parameter sonic logging group velocity phase velocity
下载PDF
Modeling and analysis of azimuthal AVO responses from a viscoelastic anisotropic reflector 被引量:4
3
作者 郭智奇 刘喜武 +1 位作者 符伟 李向阳 《Applied Geophysics》 SCIE CSCD 2015年第3期441-452,470,共13页
We propose a method for mOdeling azimuthal AVO responses from a fractured i reflector. The method calculates the integrated reflected wavetrains, and the wavetrains contain elastodynamic information including the con... We propose a method for mOdeling azimuthal AVO responses from a fractured i reflector. The method calculates the integrated reflected wavetrains, and the wavetrains contain elastodynamic information including the contrast in impedance and anelasticity i across interfaces, the intemal anisotropic propagation, the dispersion and attenuation along i the wave path, and tuning and interference. The results suggest that for large angles of incidence, the velocity dispersion and attenuation increase the amplitudes of PP waves from the top and decrease those from the bottom. For azimuthal responses at specific angles of incidence, the reflected wavetrains of PP waves tend to have longer duration with increasing azimuth. In contrast, model-converted PSV and PSH reflections show stable azimuthal features and are less affected by the reflector thickness. The amplitudes of PSV reflections increase with increasing azimuth; moreover, the waves have no reflection energy at 0° and 90° azimuth and maximum amplitude at 45° azimuth. 展开更多
关键词 REFLECTOR viscoelastic and anisotropic dispersion and attenuation generalized anisotropic Zoelopritz theory azimuthal AVO
下载PDF
Energy Shift Caused by Non-isotropy of 2-Dimensional Anisotropic Quantum Dot in Presence of Uniform Magnetic Field
4
作者 FAN Hong-Yi XU Xue-Fen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4X期615-618,共4页
Based on the squeezing mechanism in quantum dots in the presence of uniform magnetic field, we derive the energy shift caused by the non-isotropy of 2-dimensional anisotropic quantum dot. We also study sudden squeezin... Based on the squeezing mechanism in quantum dots in the presence of uniform magnetic field, we derive the energy shift caused by the non-isotropy of 2-dimensional anisotropic quantum dot. We also study sudden squeezing of the size of the quantum dot. The whole discussion is proceeded smoothly by virtue of the entangled state representation. 展开更多
关键词 squeezed Landau state anisotropic quantum dot sudden squeezing
下载PDF
釋甲骨文“[雨各]”及相關諸字——從一版氣象背甲談起
5
作者 王子楊 《出土文献综合研究集刊》 2023年第1期1-25,共25页
本文以清晰的甲骨照片爲依據,重新釋讀了《合集》21936這版龜背甲的兩條卜辭,指出這兩條卜辭占問的内容爲殷代氣象,從而揭示出這版龜背甲的價值。同時,釋出本版寫法特殊的“啓”“雷”和“[雨各]”三字,豐富了我們對商代文字形體複雜性... 本文以清晰的甲骨照片爲依據,重新釋讀了《合集》21936這版龜背甲的兩條卜辭,指出這兩條卜辭占問的内容爲殷代氣象,從而揭示出這版龜背甲的價值。同時,釋出本版寫法特殊的“啓”“雷”和“[雨各]”三字,豐富了我們對商代文字形體複雜性的認識。本文還以“[雨各]”字考釋爲契機,連帶討論了甲骨文“玫”“[女各]”“烙”諸字的釋讀,或講解用法,或分析形體結構,提出了一些新的看法。 展开更多
关键词 甲骨文 文字考釋 [雨各] [女各]
下载PDF
Research on ray tracing in VTI medium based on different models
6
作者 JI Songda SUN Jianguo +3 位作者 GAO Zhenghui SUN Hui WANG Qianlong HUANG Xinguo 《Global Geology》 2015年第4期245-251,共7页
The study on seismic anisotropy is one of the difficult problems in the field of geophysics nowadays.As a method of ray theory,the seismic anisotropy ray tracing is an important means to study the anisotropic seismic ... The study on seismic anisotropy is one of the difficult problems in the field of geophysics nowadays.As a method of ray theory,the seismic anisotropy ray tracing is an important means to study the anisotropic seismic wave propagation. The traditional ray tracing system formulated in terms of elastic parameters in the anisotropy is more complicated than that in the isotropic case. Considering the difficulty,a kind of ray tracing system formulated in terms of phase velocity and group velocity is introduced. The new method is similar to the expressions for isotropic media,and avoids the trouble of determining the eigenvalue vector at each time. Besides the ray tracing numerical simulation of different models of vertical transversely isotropic( VTI) medium is carried out,in order to verify the accuracy and applicability of the method and further study the characteristics of wave field propagation in different VTI mediums. The study is certainly valuable in reference for later processing of the anisotropic seismic data. 展开更多
关键词 VTI medium ray tracing phase velocity model trial
下载PDF
Quantum Phase Transition in Quasi-two-dimensional Heisenberg Antiferromagnet with Single-Ion Anisotropy
7
作者 JI An-Chun TIAN Guang-Shan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第1期171-180,共10页
In the present paper, we investigate the quantum phase transition in a spatially anisotropic antiferrornagnetic Heisenberg model of S =1 with single-ion energy anisotropy. By using the Schwinger boson representation, ... In the present paper, we investigate the quantum phase transition in a spatially anisotropic antiferrornagnetic Heisenberg model of S =1 with single-ion energy anisotropy. By using the Schwinger boson representation, we calculate the Gaussian correction to the critical value J⊥^c caused by quantum spin fluctuations. We find that, for the positive single-ion energy, a nonzero value of J⊥^c is always needed to stabilize the antiferromagnetic long-range order in this model. It resolves a difference among literature and shows clearly that the effect of quantum fluctuations may qualitatively change a result obtained by the mean-field theories on lower-dimensional systems. 展开更多
关键词 spatially anisotropic Heisenberg model single-ion anisotropy functional integration Schwinger-Boson representation
下载PDF
Effects of Staggered Magnetic Field on Entanglement in the Anisotropic XY Model
8
作者 SUN Zhe WANG Xiao-Guang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1期61-66,共6页
We investigate effects of staggered magnetic field on thermal entanglement in the anisotropic XY model. The analytic results of entanglement for the two-site cases are obtained. For the general case of even sites, we ... We investigate effects of staggered magnetic field on thermal entanglement in the anisotropic XY model. The analytic results of entanglement for the two-site cases are obtained. For the general case of even sites, we show that when the anisotropic parameter is zero, the entanglement in the XY model with a staggered magnetic field is the same as that with a uniform magnetic field. 展开更多
关键词 thermal entanglement staggered magnetic field anisotropic XY model
下载PDF
Integral Equation Method for Electromagnetic Wave Propagation in Stratified Anisotropic Dielectric-Magnetic Materials 被引量:1
9
作者 舒维星 付娜 +3 位作者 吕小方 罗海陆 文双春 范滇元 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第11期879-885,共7页
We investigate the propagation of electromagnetic waves in stratified anisotropic dielectric-magnetic materialsusing the integral equation method (IEM).Based on the superposition principle, we use Hertz vector formula... We investigate the propagation of electromagnetic waves in stratified anisotropic dielectric-magnetic materialsusing the integral equation method (IEM).Based on the superposition principle, we use Hertz vector formulations ofradiated fields to study the interaction of wave with matter.We derive in a new way the dispersion relation, Snell's lawand reflection/transmission coefficients by self-consistent analyses.Moreover, we find two new forms of the generalizedextinction theorem.Applying the IEM, we investigate the wave propagation through a slab and disclose the underlyingphysics, which are further verified by numerical simulations.The results lead to a unified framework of the IEM for thepropagation of wave incident either from a medium or vacuum in stratified dielectric-magnetic materials. 展开更多
关键词 integral equation stratified dielectric-magnetic materials extinction theorem METAMATERIALS
下载PDF
Three-dimensional stability analysis of anisotropic and non-homogeneous slopes using limit analysis 被引量:6
10
作者 韩长玉 陈锦剑 +1 位作者 夏小和 王建华 《Journal of Central South University》 SCIE EI CAS 2014年第3期1142-1147,共6页
A method of three-dimensional loaded slope stability for anisotropic and nonhomogeneous slopes was presented based on the upper-bound theorem of the limit analysis approach. The approach can be considered as a modific... A method of three-dimensional loaded slope stability for anisotropic and nonhomogeneous slopes was presented based on the upper-bound theorem of the limit analysis approach. The approach can be considered as a modification and extension of the solutions. The influences of friction angle, anisotropy factor, nonhomogeneous factor, slope angle, ratio of width to depth, and load on the slope crest were investigated. The results show that solutions are suitable to deal with the purely cohesive soils and frictional/cohesive soils, isotropic and anisotropic, homogeneous and nonhomogeneous, loaded and unloaded cases. 展开更多
关键词 stability ANISOTROPY limit analysis loaded slope nonhomogeneous slope
下载PDF
甲骨文“各”“■”源流考辨
11
作者 郑春兰 《语言研究》 CSSCI 北大核心 2014年第1期33-36,共4页
"各"、"■"见于甲骨文。早期甲骨文形体,其下面构件有"凵"、"口"两选,以"口"居多并成为"各"字后世的基本构件。"■"是"各"的异体字,于殷廪辛、康丁... "各"、"■"见于甲骨文。早期甲骨文形体,其下面构件有"凵"、"口"两选,以"口"居多并成为"各"字后世的基本构件。"■"是"各"的异体字,于殷廪辛、康丁时期出现,其语义取"来、至"。"各"、"■"并行于两周,以"各"为主,铭文记录表示"来、到","■"自西周中期以后便退出书面语言的使用,与之相应"格"出现。"各"、"■"二字的"来、至"义后为"格"所取代,"各"及其异体字或发生语义变化,或仅保留在方言、字书中。 展开更多
关键词 [彳各] 形音义 源流
原文传递
Simulation of biatrial conduction via different pathways during sinus rhythm with a detailed human atrial model 被引量:3
12
作者 Dong-dong DENG Ying-lan GONG +4 位作者 Guo-fa SHOU Pei-feng JIAO Heng-gui ZHANG Xue-song YE Ling XIA 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2012年第9期676-694,共19页
In order to better understand biatrial conduction,investigate various conduction pathways,and compare the differences between isotropic and anisotropic conductions in human atria,we present a simulation study of biatr... In order to better understand biatrial conduction,investigate various conduction pathways,and compare the differences between isotropic and anisotropic conductions in human atria,we present a simulation study of biatrial conduction with known/assumed conduction pathways using a recently developed human atrial model.In addition to known pathways:(1) Bachmann's bundle(BB),(2) limbus of fossa ovalis(LFO),and(3) coronary sinus(CS),we also hypothesize that there exist two fast conduction bundles that connect the crista terminalis(CT),LFO,and CS.Our simulation demonstrates that use of these fast conduction bundles results in a conduction pattern consistent with experimental data.The comparison of isotropic and anisotropoic conductions in the BB case showed that the atrial working muscles had small effect on conduction time and conduction speed,although the conductivities assigned in anisotropic conduction were two to four times higher than the isotropic conduction.In conclusion,we suggest that the hypothesized intercaval bundles play a significant role in the biatrial conduction and that myofiber orientation has larger effects on the conduction system than the atrial working muscles.This study presents readers with new insights into human atrial conduction. 展开更多
关键词 Cardiac electrophysiology Conduction Human atrial model MODELING
原文传递
Few-layer Tellurium:one-dimensional-like layered elementary semiconductor with striking physical properties 被引量:14
13
作者 Jingsi Qiao Yuhao Pan +3 位作者 Feng Yang Cong Wang Yang Chai Wei Ji 《Science Bulletin》 SCIE EI CSCD 2018年第3期159-168,共10页
Few-layer Tellurium, an elementary semiconductor, succeeds most of striking physical properties that black phosphorus(BP) offers and could be feasibly synthesized by simple solution-based methods. It is comprised of n... Few-layer Tellurium, an elementary semiconductor, succeeds most of striking physical properties that black phosphorus(BP) offers and could be feasibly synthesized by simple solution-based methods. It is comprised of non-covalently bound parallel Te chains, among which covalent-like feature appears.This feature is, we believe, another demonstration of the previously found covalent-like quasi-bonding(CLQB) where wavefunction hybridization does occur. The strength of this inter-chain CLQB is comparable with that of intra-chain covalent bonding, leading to closed stability of several Te allotropes. It also introduces a tunable bandgap varying from nearly direct 0.31 eV(bulk) to indirect 1.17 eV(2L) and four(two) complex, highly anisotropic and layer-dependent hole(electron) pockets in the first Brillouin zone.It also exhibits an extraordinarily high hole mobility(~10~5 cm^2/Vs) and strong optical absorption along the non-covalently bound direction, nearly isotropic and layer-dependent optical properties, large ideal strength over 20%, better environmental stability than BP and unusual crossover of force constants for interlayer shear and breathing modes. All these results manifest that the few-layer Te is an extraordinary-high-mobility, high optical absorption, intrinsic-anisotropy, low-cost-fabrication, tunable bandgap, better environmental stability and nearly direct bandgap semiconductor. This ‘‘one-dimen sion-like" few-layer Te, together with other geometrically similar layered materials, may promote the emergence of a new family of layered materials. 展开更多
关键词 Two-dimensional systems First-principles calculations Tellurium High carrier mobility Covalent-like quasi-bonding One-dimension-like layered materials
原文传递
Analytic solution to the magnetotelluric response over anisotropic medium and its discussion 被引量:3
14
作者 QIN LinJiang YANG ChangFu CHEN Kun 《Science China Earth Sciences》 SCIE EI CAS 2013年第9期1607-1615,共9页
In the present paper,from the second order partial differential equations for solving the magnetotelluric(MT) fields of general anisotropic medium,we first obtained the second order partial differential equations for ... In the present paper,from the second order partial differential equations for solving the magnetotelluric(MT) fields of general anisotropic medium,we first obtained the second order partial differential equations for some anisotropic media with special conductivity(e.g.diagonal anisotropy,transverse anisotropy,azimuthal anisotropy,etc.) by simplifying the electrical conductivity tensor of anisotropic medium.And then we obtained the analytic solutions to MT fields for the case of transverse and azimuthal anisotropy through converting the conductivity parameter based on that of diagonal anisotropy.We further discussed the influence of the selection of integral limit and step length on precision in solving the analytic solutions for MT fields of isotropic medium.Finally,we presented the MT responses of two transverse and azimuthal anisotropic media as well as some applications of the analytic solutions to MT fields of anisotropic medium. 展开更多
关键词 Analytic solution to the magnetotelluric response over anisotropic medium and its discussion
原文传递
Mechanical Response of Steel Wire Wound Reinforced Rubber Flexible Pipe under Internal Pressure 被引量:3
15
作者 谷凡 黄承逵 +1 位作者 周晶 李林普 《Journal of Shanghai Jiaotong university(Science)》 EI 2009年第6期747-756,共10页
Steel wire wound reinforced flexible pipe in this study mainly consists of multiple anisotropic steel wire wound reinforcement layers and multiple isotropic rubber layers.Based on 3D anisotropic elastic theory,the ana... Steel wire wound reinforced flexible pipe in this study mainly consists of multiple anisotropic steel wire wound reinforcement layers and multiple isotropic rubber layers.Based on 3D anisotropic elastic theory,the analytic solutions of stresses and elastic deformations of steel wire wound reinforced rubber flexible pipe under internal pressure are presented.As the adjacent reinforcement layers with wound angle have different radii,the single reinforcement layer shows the effect of tensile-shear coupling.Moreover,the static loading test results of steel wire wound reinforced rubber flexible pipe under internal pressure are basically coincided with the calculated values by present method. 展开更多
关键词 steel wire wound reinforced rubber flexible pipe anisotropic elastic theory tensile-shear coupling
原文传递
Quantum Correlations in Infinite XY Spin-1/2 Chains and Quantum Phase Transition 被引量:2
16
作者 谭小东 黄寿胜 金柏琪 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第2期146-156,共11页
We examine the ability of quantum discord (QD) and entanglements (concurrence, EoF and negativity) to detect the critical points associated to quantum phase transitions (QPTs) for XY models, i.e., the isotropic XY mod... We examine the ability of quantum discord (QD) and entanglements (concurrence, EoF and negativity) to detect the critical points associated to quantum phase transitions (QPTs) for XY models, i.e., the isotropic XY model with three-spin interactions at zero temperature, and the anisotropic XY model in a transverse magnetic field h at finite temperatures. For the case of zero temperature, we found that both entanglements and QD can spotlight the critical points of QPTs for these two models. Moreover, QD versus distance M exhibits the long-range behavior of quantum correlation for the anisotropic XY model, while entanglement is short-ranged. For the case of finite temperatures, we found that negativity has the same behaviors with concurrence at or near transition points. Moreover, QD for the anisotropic XY model can increase with temperature even in the absence of a magnetic field. 展开更多
关键词 thermal quantum discord quantum phase transition XY model
原文传递
Thickness-driven spin reorientation transition in ultrathin films
17
作者 MIAO BingFeng MILLEV YonkoTimtchev +3 位作者 SUN Liang YOU Biao ZHANG Wei DING HaiFeng 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第1期70-84,共15页
We review recent studies by different experimental means of ultrathin films,exhibiting thickness-driven spin reorientation transitions(SRTs).The stage is set by determining,via phenomenological thermodynamic descripti... We review recent studies by different experimental means of ultrathin films,exhibiting thickness-driven spin reorientation transitions(SRTs).The stage is set by determining,via phenomenological thermodynamic description,of the relevant phase diagrams for the possible types of SRT with and without applied magnetic field.Suitable representation may be chosen such that best use is made of the linear character(under thickness variation) of the system's path in anisotropy space.The latter involves higher-order bulk and surface anisotropies in a substantial way.We examine sensitive experimental techniques for the detection and quantification of SRTs,such as hysteresis measurements with magneto-optical Kerr effect(MOKE),micromagnetic studies utilizing scanning electron microscopy with polarization analysis(SEMPA),photoemission electron microscopy(PEEM) and spin-polarized low-energy electron microscopy(SPLEEM) as well as ac magnetic susceptibility measurements via MOKE.Key issues are conclusively discussed including the identification of reliable experimental fingerprints about whether a given SRT proceeds via a phase of coexistence or via a cone(canted) phase.We demonstrate how the application of the general theoretical ideas to carefully designed measurements leads to the determination of the most important material parameters in any ultrathin-film SRT,namely,the surface(interface) magnetic anisotropy constants.The review concludes by our personal outline for future promising work on SRTs. 展开更多
关键词 ultrathin magnetic films spin reorientation transitions magnetic anisotropy
原文传递
Stability of Quark Star Models
18
作者 M.Azam S.A.Mardan M.A.Rehman 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第5期575-584,共10页
In this paper,we investigate the stability of quark stars with four different types of inner matter configurations;isotropic,charged isotropic,anisotropic and charged anisotropic by using the concept of cracking.For t... In this paper,we investigate the stability of quark stars with four different types of inner matter configurations;isotropic,charged isotropic,anisotropic and charged anisotropic by using the concept of cracking.For this purpose,we have applied local density perturbations technique to the hydrostatic equilibrium equation as well as on physical parameters involved in the model.We conclude that quark stars become potentially unstable when inner matter configuration is changed and electromagnetic field is applied. 展开更多
关键词 quark stars cracking density perturbations electromagnetic field
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部