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Orientation and Structure of Ionic Liquid Cation at Air/[bmim][BF4] Aqueous Solution Interface 被引量:1
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作者 Gang-hua Deng Xia Li +3 位作者 You-qi Guo Shi-lin Liu Zhou Lu Yuan Guo 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第5期569-575,I0004,共8页
watermiscible 房间温度离子的液体 1butyl3methylimidazolium tetrafluoroborate ([bmim ][BF4 ]) 是为学习在离子的液体和水分子之间的相互作用的一个模型系统。在这个工作低集中的水的解决方案的 orientational 结构[bmim ][BF4 ] ... watermiscible 房间温度离子的液体 1butyl3methylimidazolium tetrafluoroborate ([bmim ][BF4 ]) 是为学习在离子的液体和水分子之间的相互作用的一个模型系统。在这个工作低集中的水的解决方案的 orientational 结构[bmim ][BF4 ] 在空气 / 液体,接口被和频率产生调查震动的光谱学。在很低的集中,丁基链展出了一个重要笨拙的缺点,这被发现了,显示混乱符合构造;并且与在表面的一个相当小的倾斜角度面向的阳离子戒指。当集中增加了时,阳离子戒指趋于在表面,和丁基链的笨拙的缺点完全躺着由于分子间的 chainchain 相互作用减少了并且作为结果更多的订的界面的分子的安排。另外,在 PPP 和 SPS 系列的反对称的拉长模式展出了山峰移动,证明那在那里多于为丁基 CH3 组的一个种取向或化学环境存在。这些结果可以在理解象 imidazolium 一样的离子的液体基于的 watermiscible 的表面行为上打开新灯表面活化剂。 展开更多
关键词 室温离子液体 取向结构 溶液界面 水分子 阳离子 表面活性剂 相互作用 振动光谱
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Floristic diversity, regeneration status, and vegetation structure of woodlands in Metema Area, Amhara National Regional State, North-western Ethiopia 被引量:4
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作者 Haile Adamu Wale Tamrat Bekele Gemedo Dalle 《Journal of Forestry Research》 CAS CSCD 2012年第3期391-398,共8页
We studied woodland vegetation in broad-leaved deciduous woodlands of Metema in northwestern Amhara regional state, Ethiopia Our objective was to describe plant species composition, diversity, re- generation status, a... We studied woodland vegetation in broad-leaved deciduous woodlands of Metema in northwestern Amhara regional state, Ethiopia Our objective was to describe plant species composition, diversity, re- generation status, and population structure by a selective approach with a systematic sampling design. A total of 74 quadrats (each for 25 m x 25 m, spaced at intervals of 150--200 m) were sampled along established tran- sect lines following the homogeneity of the vegetation. Vegetation data including cover-abundance, height, diameter at breast height (DBH), and numbers of seedlings and saplings of woody species were analyzed using Excel spreadsheet, Shannon Weiner diversity index, and PAST version 1.62. A total of 87 vascular plant species of 74 genera and 36 families were recorded. The dominant family was Fabaceae represented by 16 (18.39 %) species of 13 genera. Shannon Weiner diversity and evenness were 3.67 and 0.82, respectively, which showed that the area was en- dowed with rich floral diversity evenly distributed. The vegetation structure, as quantified by cumulative diameter class frequency distribution, plotted as an interrupted inverted-J- shape pattern with a sharp decrease in the 2nd diameter class. This indicated poor vegetation structure. The diameter classes frequency distributions of selected species plotted in four general patterns i.e., interrupted Inverted-J-shape, J-shape, Bell-shape and Irregular-shape. In conclusion, although the area showed high floral diversity and evenness, woody species including Sterculea setigera, Boswellia papyrifera, and Pterocarpus lucens showed lowest recruitment of seedlings and saplings. 展开更多
关键词 EQUITABILITY diversity DRYLAND Metema Woodland popula- tion structure REGENERAtion
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Structure formation of entanglement entropy in a system of two superconducting qubits coupled with an LC-resonator 被引量:1
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作者 葛国勤 覃翠 +1 位作者 尹淼 黄勇华 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第8期39-46,共8页
This paper investigates theoretically the evolutions of the entanglement entropy of a system of two coupled-charge- qubits interacting with an LC-resonator. It is found that when the initial states of the two qubits a... This paper investigates theoretically the evolutions of the entanglement entropy of a system of two coupled-charge- qubits interacting with an LC-resonator. It is found that when the initial states of the two qubits are prepared in a given superposition excited state, the evolution of the von Neumann entropy of the system depends significantly on the coupling strength between the two Josephson charge qubits. With the variation of the coupling strength, the evolution of the entanglement entropy of the system forms some structures, especially the periodically bistable properties, which are the first discovered for such a system to our knowledge. It is found that the relative entropy entanglement of the system is also sensitive to the variation of the coupling strength between the two charge qubits, some novel 'collective oscillations' of the relative entropy are found for the system. 展开更多
关键词 superconducting quantum circuits evolutions of entanglement entropy structure forma-tion
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Information in the Structure of Reality:the Scientific Worldview and the Fundamental Question of Philosophy
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作者 Konstantin Kolin 《学术界》 CSSCI 北大核心 2015年第1期257-260,共4页
We offer a new understanding of the scientific world and the contents of the basic question of philosophy,which is based on an analysis of the phenomenon of the specific information in the various components of the st... We offer a new understanding of the scientific world and the contents of the basic question of philosophy,which is based on an analysis of the phenomenon of the specific information in the various components of the structure of reality.It is shown that,in addition to material objects,processes,and events,in the real world are also intangible objects,processes and conditions that are in its information content.So the basic question of philosophy is proposed to treat the relationship as a tangible and intangible component of reality.More succinctly it can be formulated as the ratio of matter and information.This allows you to point to some new challenges studying the phenomenon of information in various components of the structure of reality. 展开更多
关键词 结构信息 科学世界观 哲学 组成部分 现实世界 信息内容 事件
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Filtering algorithm of line structured light for long-distance obstacle detection
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作者 邵海燕 张振海 李科杰 《Journal of Beijing Institute of Technology》 EI CAS 2016年第4期521-525,共5页
Since unmanned ground vehicles often encounter concave and convex obstacles in wild ground, a filtering algorithm using line structured light to detect these long distance obstacles is proposed. For the line structure... Since unmanned ground vehicles often encounter concave and convex obstacles in wild ground, a filtering algorithm using line structured light to detect these long distance obstacles is proposed. For the line structured light image, a ranked-order based adaptively extremum median (RAEM) filter algorithm on salt and pepper noise is presented. In the algorithm, firstly effective points and noise points in a filtering window are differentiated; then the gray values of noise points are replaced by the medium of gray values of the effective pixels, with the efficient points' gray values unchanged; in the end this algorithm is proved to be efficient by experiments. Experimental resuits demonstrate that the image blur, resulting into proposed algorithm can remove noise points effectively and minimize the protecting the edge information as much as possible. 展开更多
关键词 unmanned ground vehicles line structured light concave and convex obstacles detec-tion ranked-order based adaptively extremum median (RAEM) filter filter algorithm
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Influence of environmental factors on corrosion damage of aircraft structure 被引量:4
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作者 Keliang Ren,) Shiwu Gao, Pingping Liu, and Yan Dong Department of Physics & Electrical Information, Ningxia University, Ningxia 750021, China 《Theoretical & Applied Mechanics Letters》 CAS 2011年第6期18-21,共4页
Corrosion is one of the important structural integrity concerns of aging aircraft, and it is estimated that a significant portion of airframe maintenance budgets is directed towards corrosion-related problems for both... Corrosion is one of the important structural integrity concerns of aging aircraft, and it is estimated that a significant portion of airframe maintenance budgets is directed towards corrosion-related problems for both military and commercial aircraft. In order to better understand how environmental factors influence the corrosion damage initiation and propagation on aircraft structure and to predict pre-corrosion test pieces of fatigue life and structural integrity of an effective approach, this paper uses the cellular automaton (CA) method to character the effect of electrolyte concentrations, dissolution probabilities, and temperature on the corrosion damage of a metal structure exposed to an aggressive environment, and the procedure for applying the local rules between the cells of the CA to simulate the corrosion damage evolution is formulated. The simulation results show that the different electrolyte concentrations, dissolution probabilities and temperature, the laws of the dissolution current with time are investigated and they obey the time power function. 展开更多
关键词 aircraft structure corrosion damage environmental factors cellular automaton simula- tions
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Crystal Structure and Electronic Structure of a Luminescent Compound 2-(2-Pyridyl) Benzimidazole 被引量:1
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作者 岳淑美 苏忠民 +3 位作者 马建方 廖奕 阚玉和 张恒君 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第2期174-178,共5页
The crystal structure of 2-(2-pyridyl) benzimidazole was determined by single- crystal X-ray diffraction at 193(2) K. It crystallizes in orthorhombic system, space group Pbca with unit cell constants a = 10.6204(7), b... The crystal structure of 2-(2-pyridyl) benzimidazole was determined by single- crystal X-ray diffraction at 193(2) K. It crystallizes in orthorhombic system, space group Pbca with unit cell constants a = 10.6204(7), b = 10.1407(4), c = 18.6327(8) , Z = 8, V = 2006.7(2) 3, Dc = 1.292 g/cm3, F(000) = 816 and m(MoK) = 0.081 mm-1. The structure was refined to R = 0.0317 and wR = 0.0454 for 795 observed reflections with I > 2s(I). In the solid state, it has an emission maximum at 369 nm, while in solution (DMSO), the maximum excitation is at 372 nm. Quantum chemistry calculation was performed by the method of density functional theory. Theoretical results show that atom N is the reactive site when coordinating with a metal, and the electronic structure of the title compound presents excellent carrier transport properties. 展开更多
关键词 pyridyl) benzimidazole LUMINESCENT synthesis quantum chemistry calcula- tion crystal structure
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Darboux Transformation and New Soliton-like Solutions for (1+1)-Dimensional Higher-Order Broer-Kaup System 被引量:1
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作者 YU Rui HUANG Ding-Jiang ZHANG Hong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期401-404,共4页
在这封信,我们构造一种新 Darboux 转变为(1+1 ) 在计量器转变的帮助下的维的高顺序的 Broer-Kaup (HBK ) 系统一光谱问题。由使用这新 Darboux 转变,一些新象 soliton 一样答案(1+1 ) 维的 HBK 系统被获得。
关键词 孤立子解法 高次序Broer-Kaup系统 量规变换 光谱问题
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GLOBAL EXISTENCE AND BLOW-UP OF SOLUTIONS FOR GENERALIZED POCHHAMMER-CHREE EQUATIONS 被引量:1
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作者 徐润章 刘亚成 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1793-1807,共15页
In this article, we study the initial boundary value problem of generalized Pochhammer-Chree equation utt-uxx-uxxt-uxxtt=f(u)xx,x∈Ω,t〉0,u(x,0)=u0(x),ut(x,0)=u1(x),x∈Ω,u(0,t)=u(1,t)=0,t≥0, where Ω... In this article, we study the initial boundary value problem of generalized Pochhammer-Chree equation utt-uxx-uxxt-uxxtt=f(u)xx,x∈Ω,t〉0,u(x,0)=u0(x),ut(x,0)=u1(x),x∈Ω,u(0,t)=u(1,t)=0,t≥0, where Ω = (0, 1). First, we obtain the existence of local Wkp solutions. Then, we prove that, if f(s) ∈ Ck+1(R) is nondecreasing, f(0) = 0 and |f(u)| ≤ C1|u|∫0uf(s)ds + C2, u0(x),u1(x) ∈ WkP(Ω) ∩ W01,P(Ω), k≥ 1, 1 〈 p≤ ∞, then for any T 〉 0 the problem admits a unique solution u(x, t) ∈ W2,∞(0, T; WkP(Ω) ∩ W01,P(Ω)). Finally, the finite time blow-up of solutions and global Wkp solution of generalized IMBo equations are discussed. 展开更多
关键词 Pochhammer-Chree equations initial boundary value problem Wkp solu-tion global existence BLOW-UP
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DEEP-UV CONFOCAL FLUORESCENCE IMAGING AND SUPER-RESOLUTION OPTICAL MICROSCOPY OF BIOLOGICAL SAMPLES
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作者 TREVOR A.SMITH LIISA M.HIRVONEN +1 位作者 CRAIG N.LINCOLN XIAOTAO HAO 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2012年第4期24-32,共9页
A wide range of techniques has been developed to image biological samples at high spatial and temporal resolution.In this paper,we report recent results from deep-UV confocal fAuorescence microscopy to image inherent ... A wide range of techniques has been developed to image biological samples at high spatial and temporal resolution.In this paper,we report recent results from deep-UV confocal fAuorescence microscopy to image inherent emission from fuorophores such as tryptophan,and structured ilumination microscopy(SIM)of biological materials.One motivation for developing deep-UV fhuorescence imaging and SIM is to provide methods to complement our measurements in the emerging field of X-ray coherent diffractive imaging. 展开更多
关键词 Time resolved fuorescence imaging structured ilumnina tion microscopy
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Benchmark solutions for sound propagation in an ideal wedge
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作者 骆文于 杨春梅 +1 位作者 秦继兴 张仁和 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期346-354,共9页
Sound propagation in a wedge-shaped waveguide with perfectly reflecting boundaries is one of the few range- dependent problems with an analytical solution, and hence provides an ideal benchmark for a full two-way solu... Sound propagation in a wedge-shaped waveguide with perfectly reflecting boundaries is one of the few range- dependent problems with an analytical solution, and hence provides an ideal benchmark for a full two-way solution to the wave equation. An analytical solution for the sound propagation in an ideal wedge with a pressure-release bottom was presented by Buckingham and Tolstoy [Buckingham and Tolstoy 1990 J. Acoust. Soc. Am. 87 1511]. The ideal wedge problem with a rigid bottom is also of great importance in underwater acoustics. We present an analytical solution to the ideal wedge problem with a perfectly reflecting bottom, either rigid or pressure-release, which may be used to provide a means for investigating the sound field in depth-varying channels, and to establish the accuracy of numerical propagation models. Closed-form expressions for coupling matrices are also provided for the ideal waveguides characterized by a ho- mogeneous water column bounded by perfectly reflecting boundaries. A comparison between the analytical solution and the numerical solution recently proposed by Luo et al. [Luo W Y, Yang C M and Zhang R H 2012 Chin. Phys. Lett. 29 014302] is also presented, through which the accuracy of this numerical model is illustrated. 展开更多
关键词 coupled-mode theory wedge-shaped waveguide perfectly reflecting boundary benchmark solu-tion
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The dynamics of nonstationary solutions in one-dimensional two-component Bose-Einstein condensates
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作者 吕彬彬 郝雪 田强 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第2期60-69,共10页
This paper investigates the dynamical properties of nonstationary solutions in one-dimensional two-component Bose-Einstein condensates. It gives three kinds of stationary solutions to this model and develops a general... This paper investigates the dynamical properties of nonstationary solutions in one-dimensional two-component Bose-Einstein condensates. It gives three kinds of stationary solutions to this model and develops a general method of constructing nonstationary solutions. It obtains the unique features about general evolution and soliton evolution of nonstationary solutions in this model. 展开更多
关键词 two-component Bose Einstein condensates stationary solutions nonstationary solu-tions soliton approximation
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Periodic Wave Solutions and Solitary Wave Solutions of the (2+1)-Dimensional Korteweg-de-Vries Equatio
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作者 Liangwei He Shuanghong Chen 《American Journal of Computational Mathematics》 2021年第4期327-339,共13页
In this paper, we investigate the periodic wave solutions and solitary wave solutions of a (2+1)-dimensional Korteweg-de Vries (KDV) equation</span><span style="font-size:10pt;font-family:"">... In this paper, we investigate the periodic wave solutions and solitary wave solutions of a (2+1)-dimensional Korteweg-de Vries (KDV) equation</span><span style="font-size:10pt;font-family:""> </span><span style="font-size:10pt;font-family:"">by applying Jacobi elliptic function expansion method. Abundant types of Jacobi elliptic function solutions are obtained by choosing different </span><span style="font-size:10.0pt;font-family:"">coefficient</span><span style="font-size:10.0pt;font-family:"">s</span><span style="font-size:10pt;font-family:""> <i>p</i>, <i>q</i> and <i>r</i> in the</span><span style="font-size:10pt;font-family:""> </span><span style="font-size:10pt;font-family:"">elliptic equation. Then these solutions are</span><span style="font-size:10pt;font-family:""> </span><span style="font-size:10pt;font-family:"">coupled into an auxiliary equation</span><span style="font-size:10pt;font-family:""> </span><span style="font-size:10pt;font-family:"">and substituted into the (2+1)-dimensional KDV equation. As <span>a result,</span></span><span style="font-size:10pt;font-family:""> </span><span style="font-size:10pt;font-family:"">a large number of complex Jacobi elliptic function solutions are ob</span><span style="font-size:10pt;font-family:"">tained, and many of them have not been found in other documents. As</span><span style="font-size:10pt;font-family:""> </span><span style="font-size:10.0pt;font-family:""><span></span></span><span style="font-size:10pt;font-family:"">, some complex solitary solutions are also obtained correspondingly.</span><span style="font-size:10pt;font-family:""> </span><span style="font-size:10pt;font-family:"">These solutions that we obtained in this paper will be helpful to understand the physics of the (2+1)-dimensional KDV equation. 展开更多
关键词 Nonlinear Evolution Equations Jacobi Elliptic Function (2+1)-Dimensional KDV Periodic Wave solutions Solitary Wave solu-tions
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政策视角下我国档案利用服务中部门合作结构与演进
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作者 胡吉明 阳巧英 《北京档案》 北大核心 2024年第5期7-13,共7页
厘清档案利用服务中的部门合作结构与演进特征,有助于促进部门协同机制建设,并提升档案利用服务水平。本文以中央层级档案利用服务相关政策为研究对象,将我国档案利用服务政策演进分为政策初创阶段、政策深化阶段、政策体系化阶段与政... 厘清档案利用服务中的部门合作结构与演进特征,有助于促进部门协同机制建设,并提升档案利用服务水平。本文以中央层级档案利用服务相关政策为研究对象,将我国档案利用服务政策演进分为政策初创阶段、政策深化阶段、政策体系化阶段与政策转型阶段,这四个阶段呈现参与政策制定的部门逐渐增多,“高位推动”转向国务院部委为主的变化。运用关联网络分析方法探讨档案利用服务中部门合作结构及其演进特征,分析发现:部门合作不断扩大及趋于集中,并形成了多元化的共同体;部门合作整体构型由“松散型”转向“中心边缘型”;部门合作局部构型则由“二元组”演变为“三元交互”。为促进跨部门政策协同,针对当前档案利用服务中部门合作规模较小、稳定性较弱,且整体连通性不强的特点,提出应充分利用全国档案查询利用服务平台,并建立档案利用服务联席会议制度的建议。 展开更多
关键词 档案利用服务 部门合作结构 政策演进 政策视角 关联网络分析
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汽车空调涡旋压缩机排气孔优化研究
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作者 刘兴旺 李远航 +3 位作者 刘晓明 李登辉 蒋强强 陈荣道 《制冷与空调》 2024年第3期83-88,共6页
针对汽车空调涡旋压缩机排气孔处气体流动变化产生的流动损失问题,对排气孔结构进行优化,以期降低流动损失并提高排气压力。通过三维动网格模型对不同排气孔结构的涡旋压缩机排气过程进行瞬态仿真,发现腰果形排气孔更大的截面积使其拥... 针对汽车空调涡旋压缩机排气孔处气体流动变化产生的流动损失问题,对排气孔结构进行优化,以期降低流动损失并提高排气压力。通过三维动网格模型对不同排气孔结构的涡旋压缩机排气过程进行瞬态仿真,发现腰果形排气孔更大的截面积使其拥有更好的开启特性,可有效降低排气损失,提高排气稳定性。在对腰果形排气孔采取进一步扩压式优化后,发现其可以更加有效地降低排气速度并提高排气压力。 展开更多
关键词 汽车空调涡旋压缩机 动网格 排气孔结构优化 排气特性 流动损失
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结构性资产负债表衰退及其宏观经济效应与政策协整
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作者 秦怡 陈平 徐飘洋 《金融经济学研究》 北大核心 2024年第2期142-167,共26页
疫后恢复政策组合拳,有力承托了中国宏观经济运行的积极因素,但当前经济下行压力依然突出,部分领域发展呈现明显波动,亟须有能够“对症下药”的理论解释和宏观政策应对。构建NK-DSGE模型,探讨结构性资产负债表衰退的宏观经济效应以及相... 疫后恢复政策组合拳,有力承托了中国宏观经济运行的积极因素,但当前经济下行压力依然突出,部分领域发展呈现明显波动,亟须有能够“对症下药”的理论解释和宏观政策应对。构建NK-DSGE模型,探讨结构性资产负债表衰退的宏观经济效应以及相应政策协整问题。研究结果展示,典型事实蕴含中国不存在总体资产负债表衰退,但存在结构性资产负债表衰退的证据。在宏观层面,结构性资产负债表衰退冲击会导致宏观经济较长时期下滑,乃至引发债务-通缩风险,而在微观层面,减轻资产负债表衰退企业的债务厌恶和改善正常经营企业的融资约束有助于减弱上述影响。调节效应分析表明,结构性资产负债表衰退会抑制技术进步与需求扩张对产出的促进作用,但在技术进步情形下,上述抑制作用有限。为减小福利损失,财政政策应盯住衰退类企业债务,货币政策应锚定高融资约束企业债务,并提高政策反应力度,宏观审慎政策应提高对资产价格的敏感度。上述结论为理解微观层面债务厌恶所产生的宏观合力以及设计实施相应政策搭配提供参考。 展开更多
关键词 结构性资产负债表衰退 宏观经济效应 政策协整 稳增长 防风险
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摩擦摆隔震地铁车站结构地震响应规律研究
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作者 韩学川 陶连金 解咏平 《防灾减灾工程学报》 CSCD 北大核心 2024年第1期146-155,共10页
基于ABAQUS软件建立土-隔震地铁车站结构静-动力耦合三维数值仿真模型,以典型两层两跨箱型结构为研究对象,将摩擦摆隔震支座应用于地铁车站结构,通过在中柱不同位置布置隔震支座,研究隔震地铁车站的地震响应规律和减隔震效果。结果表明:... 基于ABAQUS软件建立土-隔震地铁车站结构静-动力耦合三维数值仿真模型,以典型两层两跨箱型结构为研究对象,将摩擦摆隔震支座应用于地铁车站结构,通过在中柱不同位置布置隔震支座,研究隔震地铁车站的地震响应规律和减隔震效果。结果表明:(1)摩擦摆隔震支座能够增大车站侧墙和板的相对水平位移以及中柱的绝对水平位移且能够有效减小中柱的相对水平位移;从控制结构中柱相对水平位移方面考虑,单支座隔震地铁车站结构应将隔震支座布置于车站底层中柱底部位置,而双支座隔震地铁车站结构应布置于车站顶层和底层中柱柱底位置;(2)摩擦摆隔震支座能够降低隔震层中柱的应力,隔震支座布置于顶层时,其对底层各构件的应力影响较小;隔震支座布置于底层时,最大应力出现在侧墙底部位置且能够有效减小隔震层中柱应力集中的现象;(3)摩擦摆隔震支座能够有效降低隔震层中柱的剪力和弯矩,而对于非隔震层中柱内力的降低则效果不佳;从控制结构中柱内力方面考虑,双隔震支座结构优于单隔震支座结构。 展开更多
关键词 摩擦摆隔振支座 动力特性 地震响应 数值模拟 地铁车站
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基于论元结构和论元角色的英语-(a)tion型后缀动词名物词具体义研究 被引量:7
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作者 双文庭 夏子宜 马阳 《天津外国语大学学报》 2015年第3期9-14,共6页
英语双音节和多音节及物动词大多可以通过添加-(a)tion或同类后缀的形式构成相应的动词名物词。宏观上讲,这类词有具体和抽象两种意义,抽象义往往和原动词的意义十分接近,表示动作或行为本身,而具体义则可从相应动词的论元结构和论元角... 英语双音节和多音节及物动词大多可以通过添加-(a)tion或同类后缀的形式构成相应的动词名物词。宏观上讲,这类词有具体和抽象两种意义,抽象义往往和原动词的意义十分接近,表示动作或行为本身,而具体义则可从相应动词的论元结构和论元角色来找到语义依据。具体来说,具体义往往可以通过原动词论元结构中的某一论元或其上位词来表达。英语这类名物词的具体义与相应动词论元的这种内在关系的形成,与动词词义本身以及人类的认知规律均有重要联系。 展开更多
关键词 论元结构 论元角色 -(a)tion型后缀 动词名物词 具体义
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平台经济赋能实体经济发展研究——来自中国省级面板数据的证据
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作者 冯卓 吴奇 《工业技术经济》 北大核心 2024年第6期103-112,共10页
随着数字经济快速发展,平台经济逐渐成长为具有重要影响力的经济模式,其特性为实体经济的增长赋予了新的动能。本文采用2012~2022年间中国省级面板数据,研究平台经济是否能够促进实体经济发展。实证结果表明,平台经济能够显著地对实体... 随着数字经济快速发展,平台经济逐渐成长为具有重要影响力的经济模式,其特性为实体经济的增长赋予了新的动能。本文采用2012~2022年间中国省级面板数据,研究平台经济是否能够促进实体经济发展。实证结果表明,平台经济能够显著地对实体经济发展产生正向影响。进一步的研究发现,产业结构、数字普惠金融和财政分权度均能强化平台经济对实体经济发展的正向影响,上述因素在推动平台经济与实体经济融合发展中发挥重要作用。本文的研究为理解当前我国平台经济与实体经济之间的关系提供了经验证据。 展开更多
关键词 平台经济 实体经济 产业结构 数字普惠金融 财政分权度 融合发展
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基于计算机视觉和视频插帧的结构振动测试与模态识别
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作者 杨克超 李林 《福建理工大学学报》 CAS 2024年第1期22-29,38,共9页
结构振动测试和模态参数识别是基于结构动态特性进行结构健康监测(SHM)的基本方法。为克服传统接触式测试的不便,引入了非接触式计算机视觉方法,其中以智能手机为数据采集装置的方法受到越来越多的关注。然而智能手机相机往往因为性能... 结构振动测试和模态参数识别是基于结构动态特性进行结构健康监测(SHM)的基本方法。为克服传统接触式测试的不便,引入了非接触式计算机视觉方法,其中以智能手机为数据采集装置的方法受到越来越多的关注。然而智能手机相机往往因为性能受限无法满足需求,从而导致测量结果精度下降。为此,提出一种改进的视频插帧算法EQVI-T与改进的边缘检测算法,通过提高原始视频的帧率和提出的特征点追踪方法共同提升计算精度。为验证这一方法的有效性,将其应用于试验室模型的位移响应监测和模态参数识别,并进行了定量和定性评估。结果表明,所提方法在提高测量精度和准确性方面具有显著优势,展示了其在结构振动测试中的潜在应用价值。 展开更多
关键词 结构振动测试 模态识别 计算机视觉 视频插帧 注意力机制
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