Network-Based Driving Force of National Economic Development: A Social Capital Perspective

Network science has been widely applied in theoretical and empirical studies of global value chain (GVC), and many related articles have emerged, forming many more mature and complete analytical frameworks. Among them, the GVC accounting method based on complex network theory is different from the mainstream economics in both research angle and content. In this paper, we build up global industrial value chain network (GIVCN) models based on World Input–Output Database, introduce the theoretical framework of Social Capital, and define the network-based indicators with economic meanings. Second, we follow the econometric framework to analyze the hypothesis and test whether it is true. Finally, we study how the three types of capital constituted by these indicators interact with each other, and discuss their impact on the social capital (economic development level, i.e., GDP). The results prove that the structural capital (industrial status) has a positive impact on the social capital; the relational capital (industrial correlation) has a positive impact on both social capital and structural capital; the cognitive capital (industrial structure) has a small impact on the social capital, structural capital, and relational capital.     

Interplay between elasticity,ferroelectricity and magnetism at the domain walls of bismuth ferrite

Multiferroic domain walls have recently been proposed as the active element in devices related to spintronics, data storage, and magnetic logic. Among multiferroics, BiFeO₃ is by far the most studied material. Its domain walls have shown rich behaviours that include conductivity in an otherwise insulating crystal, and magnetotransport properties that are markedly different from those of the bulk. In this article we summarize the experimental evidence and the current models used to understand the interplay between elastic, electric, and magnetic properties of the domain walls. Starting from the considera‐ tion of antiferromagnetic domain structures on a background of ferroelectric domains, and emphasizing pinning effects, we proceed to discuss the microscopic behavior of ferroelectricity and magnetism at the walls. We describe how domain organization in BiFeO₃ is caused by structural transformations, and scrutinize modelling works pinpointing their characteristic features. Finally, we summarize the recent progress and list open questions for future study on BiFeO₃ domain structures. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)     

Comparing closed quotient in children singers' voices as measured by high-speed-imaging, electroglottography, and inverse filtering

The closed quotient, i.e., the ratio between the closed phase and the period, is commonly studied in voice research. However, the term may refer to measures derived from different methods, such as inverse filtering, electroglottography or high-speed digital imaging (HSDI). This investigation compares closed quotient data measured by these three methods in two boy singers. Each singer produced sustained tones on two different pitches and a glissando. Audio, electroglottographic signal (EGG), and HSDI were recorded simultaneously. The audio signal was inverse filtered by means of the decap program; the closed phase was defined as the flat minimum portion of the flow glottogram. Glottal area was automatically measured in the high speed images by the built-in camera software, and the closed phase was defined as the flat minimum portion of the area-signal. The EGG-signal was analyzed in four different ways using the matlab open quotient interface. The closed quotient data taken from the EGG were found to be considerably higher than those obtained from inverse filtering. Also, substantial differences were found between the closed quotient derived from HSDI and those derived from inverse filtering. The findings illustrate the importance of distinguishing between these quotients.     

Sound radiation from point-excited structures: Comparison of plate and sphere

Acoustic radiation from a structure can be expressed in terms of “modal radiation” and “modal coefficients”. This paper investigates the contributions of these two modal properties to radiation excited by a point force. Sound radiation from two basic structures is considered: a baffled rectangular plate and a closed spherical shell. The plate behaviour is familiar, and governed by the relation between the natural frequency of a mode and its coincidence frequency. For a closed spherical shell, there are either zero or two “critical frequencies”, depending on the radius and thickness. When there are two the shell radiates well both above and below the two frequencies, and poorly in the frequency range between them.     

利用场耦合理论研究开放微波谐振腔

利用电磁场的等效原理，将一个开放微波腔等效于一个闭合边界微波腔（即封闭微波腔）和开放边界（即行波吸收边界）两部分，然后利用等效封闭微波腔的本征模式及其与开放边界的耦合，建立了关于开放微波腔模式（即模式场分布、频率、品质因子）的耦合方程组，其中开放边界为行波吸收边界.以X波段六腔渡越振荡管为例进行分析，将该振荡管等效为封闭微波腔和同轴输出结构两部分，用SUPPERFISH获得封闭腔的各个模式场分布及频率，然后根据封闭微波腔与开放边界的耦合，求得六腔渡越振荡管的工作模频率为9.25GHz，品质因子为115.2，与实验测量结果基本符合. 关键词： 微波腔 本征模式 场耦合 渡越振荡管     

Interplay of conductance, force, and structural change in metallic point contacts

The coupling between two atomically sharp nanocontacts provides tunable access to a fundamental underlying interaction: the formation of the bond between two atoms as they are brought into contact. Here we report a detailed experimental and theoretical analysis of the relation between the chemical force and the tunneling current during bond formation in atom-scale metallic junctions and their dependence on distance, junction structure, and material. We found that the short-range force as well as the conductance in two prototypical metal junctions depend exponentially on the distance and that they have essentially the same exponents. In the transition regime between tunneling and point contact, large short-range forces generate structural relaxations which are concomitant with modifications of the surface electronic structure and the collapse of the tunneling barrier.     

浅析量子力学中的不确定性原理

德国物理学家海森伯在1927年提出的不确定性原理,包括两力学量间的不确定性原理和能量与时间的不确定性原理,它的提出意味着量子力学不仅有了完整的数学形式,而且有了合理的理论解释.本文尝试通过对不确定性原理的创立背景、过程、应用等来对这一原理做简要介绍,特别强调了科学讨论在科学发展中的作用.     

Effects of gas compressibility on the dynamics of premixed flames in long narrow adiabatic channels

We examine the dynamics of premixed flames in long, narrow, adiabatic channels focusing, in particular, on the effects of gas compressibility on the propagation. Recognising the importance of the boundary conditions, we examine and compare three cases: flame propagation in channels open at both ends, where the pressure must adjust to the ambient pressure at both ends and the expanding gas is allowed to leave the channel freely, and flame propagation in channels that remain closed at one of the two ends, where the burned/unburned gas remains trapped between the flame and one of the two walls. Earlier studies have shown that a flame accelerates when travelling down a narrow channel as a result of the combined effects of wall friction and thermal expansion. In the present work we show that compressibility effects enhance the transition to fast accelerating flames in channels open at both ends and in channels closed at the ignition end. In both situations, the accelerating flames could reach values that, depending on the effective Mach number, are as large as fifty times the laminar flame speed. In contrast, when the channel is closed at the far end, the acceleration is limited and the propagation speed is damped as the flame approaches the far boundary. Moreover, we show that, in channels closed at their ignition end, the flame in sufficiently long channels evolves into a steadily propagating compression-driven flame. The propagation speed of these flames depends exponentially on the constant-volume equilibrium temperature, which is higher than the (constant pressure) adiabatic flame temperature, and is therefore larger than for ordinary isobaric flames. Fast propagating compression waves cannot emerge in channels that remain open at their ignition end because of the reduced pressure forced by the open boundary.     

Interpretation of protein structure and dynamics from the statistics of the open and closed times measured in a single ion-channel protein

Ion channels are proteins in the lipid cell membrane. They spontaneously fluctuate between conformational shapes that are open or closed to the passage of ions. The ionic currents through an individual channel can be resolved by the patch clamp technique. Thus, the time sequence of open and closed conformational states can be measured in one channel molecule. The probability density function of the dwell times in the open and closed states displays scaling functions that may arise from: (1) a large number of conformational substates having a continuous distribution of activation energy barriers, (2) time-dependent changes in the energy barriers between states, or (3) local interactions that constrain local structures which interact hierarchically to form global structure.     

Robust Characterization of Multidimensional Scaling Relations between Size Measures for Business Firms

Although the sizes of business firms have been a subject of intensive research, the definition of a “size” of a firm remains unclear. In this study, we empirically characterize in detail the scaling relations between size measures of business firms, analyzing them based on allometric scaling. Using a large dataset of Japanese firms that tracked approximately one million firms annually for two decades (1994–2015), we examined up to the trivariate relations between corporate size measures: annual sales, capital stock, total assets, and numbers of employees and trading partners. The data were examined using a multivariate generalization of a previously proposed method for analyzing bivariate scalings. We found that relations between measures other than the capital stock are marked by allometric scaling relations. Power–law exponents for scalings and distributions of multiple firm size measures were mostly robust throughout the years but had fluctuations that appeared to correlate with national economic conditions. We established theoretical relations between the exponents. We expect these results to allow direct estimation of the effects of using alternative size measures of business firms in regression analyses, to facilitate the modeling of firms, and to enhance the current theoretical understanding of complex systems.     

On many-loop calculations in the theory of open strings

The relation between the determinant of a Laplace operator on a Riemann surface with a boundary to the determinant on the double of the surface is derived. This makes manifest the relation between theories of open and closed strings in their critical dimension.     

Interaction between human telomeric G-quadruplexes characterized by single molecule magnetic tweezers

Human telomeric G-quadruplex plays a crucial role in regulating the genome stability. Despite extensive studies on structures and kinetics of monomeric G-quadruplex, the interaction between G-quadruplexes is still in debate. In this work,we employ magnetic tweezers to investigate the folding and unfolding kinetics of two contiguous G-quadruplexes in 100-mM K~+buffer. The interaction between G-quadruplexes and the consequent effect on the kinetics of G-quadruplex are revealed. The linker sequence between G-quadruplexes is further found to play an important role in the interaction between two G-quadruplexes. Our results provide a high-resolution insight into kinetics of multimeric G-quadruplexes and genome stability.     

Mass,matter, and energy. A relativistic approach

The debate concerning the relations between matter and motion has the same age as philosophy itself. In modern times this problem was transformed into the one concerning the relations between mass and energy. Newton identified mass with matter. Classical thermodynamics brought this conception to its logical conclusion, establishing an ontic dichotomy between mass-matter and energy. On the basis of this pre-relativistic conception, Einstein's famous equation has been interpreted as a relation of equivalence between mass-matter and energy. Nevertheless, if we reject this epistemologically illegitimate identification, it is possible to elaborate a unitary conception of matter, which at the same time is an argument for the unity between matter and motion. In particular, the classical antithesis between matter and field becomes obsolete in the frame of the proposed interpretation.     

Wilson loops T-dual to short strings

We show that closed string solutions in the bulk of AdS space are related by T-duality to solutions representing an open string ending at the boundary of AdS. By combining the limit in which a closed string becomes small with a large boost, we find that the near-flat space short string in the bulk maps to a periodic open string world surface ending on a wavy line at the boundary. This open string solution was previously found by Mikhailov and corresponds to a time-like near-BPS Wilson loop differing by small fluctuations from a straight line. A simple relation is found between the shape of the Wilson loop and the shape of the closed string at the moment when it crosses the horizon of the Poincaré patch. As a result, the energy and spin of the closed string are encoded in properties of the Wilson loop. This suggests that closed string amplitudes with one of the closed strings falling into the Poincaré horizon should be dual to gauge theory correlators involving local operators and a Wilson loop of the T-dual (“momentum”) theory.     

Topics on space-time topology (III)

The paper is divided into two parts. The first part is a detailed review of the topological background to the theory of spinor structures on space-times, including proofs of most of the main results. The second part is a contination of the analysis in the second paper of this series of the cobordism theory of compact, closed, orientable space-time manifolds. A new cobordism relation is defined: linear spin cobordism and the linear spin cobordism of space-time manifolds calculated.     

Wave functions,nodal domains,flow, and vortices in open microwave systems

The signatures of wave functions in open cylindrical microwave billiards are investigated. The wave functions are obtained by means of a transmission measurement from an attached lead to a probe antenna inside the billiard. One can deduce complex wave functions and current densities of the system from the measurement. We investigate distributions and correlations of wave functions, currents and other quantities and compare this results with predictions from the random plane wave approach. Vortices and saddles are created and annihilated as a function of frequency and show a rich dynamic. Additionally we investigate nodal domains of the real and imaginary part of the wave function, their relation to the phase rigidity, and its parametric dependance on global phase shifts.     

Changing motif distributions in complex networks by manipulating rich-club connections

The role of rich-club connectivity is significant in the structural property and functional behavior of complex networks. In this study, we find whether or not a very small portion of rich nodes connected to each other can strongly affect the frequency of occurrence of basic building blocks (motifs) within a heterogeneous network. Conversely whether a homogeneous network has a rich-club or not generally has no significant effect on its structure. These findings open the possibility to optimize and control the structure of complex networks by manipulating rich-club connections. Furthermore, based on the subgraph ratio profile, we develop a more rigorous approach to judge whether a network has a rich-club or not. The new method does not calculate how many links there are among rich nodes but depends on how the links among rich nodes can affect the overall structure as well as the function of a given network.     

Emergent Universe with Exotic Matter in Brane World Scenario

In this work, we have examined the emergent scenario in brane world model for phantom and tachyonic matter. For tachyonic matter field we have obtained emergent scenario is possible for closed, open and flat model of the universe with some restriction of potential. For normal scalar field the emergent scenario is possible only for closed model and the result is identical with the work of Ellis et al. (Class. Quantum Gravity 21:223, 2004), but for phantom field the emergent scenario is possible for closed, open and flat model of the universe with some restriction of potential.     

高压下ZnO的结构、弹性性质和吸收光谱的第一性原理研究

 运用基于密度泛函理论（DFT）的平面波赝势方法（PWP）,结合局域密度近似（LDA）以及广义梯度近似（GGA）,系统地研究了ZnO的纤锌矿结构（B4结构）,NaCl结构（B1结构）和CsCl结构（B2结构）在不同压强下的几何结构、弹性性质和吸收光谱。详细研究了ZnO发生的两次相变（B4→B1及B1→B2相变）,得到了不同近似下的相变压强,以及两次相变过程中其弹性常数随压强的变化,并分析了这种变化与相变的关系。发现在高压作用下,ZnO的吸收光谱发生蓝移。通过计算结果和实验结果的比较可以看出,LDA近似下的计算结果更加符合实验结果。