Causal Non-Stationary Thermodynamics of Non-Viscous Heat Conducting Fluids with Internal Variables

Relativistic non-viscous heat conducting fluids with a vectorial internal variable are modeled according to the dissipation and causality principles. A set of constitutive equations, ensuring the causal nature of the model, is postulated. The second law of thermodynamics is exploited by analyzing a suitable covariant form of the Clausius–Duhem inequality. A modification of the classical theory of heat conduction, allowing a finite speed of propagation of thermal disturbances, is considered.     

FDI流入中国的原因分析

FDI流入我国,可提高我国经济效率,促进我国经济增长.因此,二十多年以来,我国不断为外商提供财政、税收、土地等方面的优惠政策以吸引外资的进入.但是,由资本的逐利本性我们可以认为外资流入中国并不只是受这些优惠政策的吸引.因此,我们有必要分析外资流入中国的真正原因,以便使我国政府可在引进外资时处于主动地位.本文通过定量分析与定性分析相结合的方法,得出中国经济的迅速增长是吸引外资流入的主要原因这一结论,并在此基础上对我国目前的利用外资政策提出一些建议,具有一定的现实意义.     

Universally coupled massive gravity

We derive Einstein’s equations from a linear theory in flat space-time using free-field gauge invariance and universal coupling. The gravitational potential can be either covariant or contravariant and of almost any density weight. We adapt these results to yield universally coupled massive variants of Einstein’s equations, yielding two one-parameter families of distinct theories with spin 2 and spin 0. The Freund-Maheshwari-Schonberg theory is therefore not the unique universally coupled massive generalization of Einstein’s theory, although it is privileged in some respects. The theories we derive are a subset of those found by Ogievetsky and Polubarinov by other means. The question of positive energy, which continues to be discussed, might be addressed numerically in spherical symmetry. We briefly comment on the issue of causality with two observable metrics and the need for gauge freedom and address some criticisms by Padmanabhan of field derivations of Einstein-like equations along the way. __________ Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 151, No. 2, pp. 311–336, May, 2007.     

上海股市信息散布过程实证分析

本文基于日内高频数据实证分析了上海A股、B股市场的收益率和交易量之间的同时和动态关系,实证结果表明在上海股市信息渐达假说较之混合分布假说更有一定的适用性,而且A股市场的信息不对称程度要大于B股市场,并进而带来了低效率。     

Discrete Quantum Causal Dynamics

We give a mathematical framework to describe the evolution of open quantum systems subject to finitely many interactions with classical apparatuses and with each other. The systems in question may be composed of distinct, spatially separated subsystems which evolve independently, but may also interact. This evolution, driven both by unitary operators and measurements, is coded in a mathematical structure in such a way that the crucial properties of causality, covariance, and entanglement are faithfully represented. The key to this scheme is the use of a special family of spacelike slices—we call them locative—that are not so large as to result in acausal influences but large enough to capture nonlocal correlations.     

美国旅华需求的影响因素：模型构建与检验

关于美国旅华的研究多为描述性的定性研究,定量研究较少,且对美国旅华需求的研究鲜见。因此,本文首先提出影响美国旅华需求的因素假设,然后通过Johansen协整分析,构建出相应协整模型,同时验证了假设。进一步通过Granger因果关系检验,表明影响因素的假设是有效的。从而得出结论:美国旅华需求对在华生活相对价格变化、人民币兑美元汇率变化都缺乏弹性,而对美国总人口变化及美国人均收入变化率的变化非常敏感.     

Finite‐difference time‐domain simulation of acoustic propagation in heterogeneous dispersive medium

Accurate modeling of pulse propagation and scattering is a problem in many disciplines (i.e., electromagnetics and acoustics). It is even more tenuous when the medium is dispersive. Blackstock [D. T. Blackstock, J Acoust Soc Am 77 (1985) 2050] first proposed a theory that resulted in adding an additional term (the derivative of the convolution between the causal time‐domain propagation factor and the acoustic pressure) that takes into account the dispersive nature of the medium. Thus deriving a modified wave equation applicable to either linear or nonlinear propagation. For the case of an acoustic wave propagating in a two‐dimensional heterogeneous dispersive medium, a finite‐difference time‐domain representation of the modified linear wave equation can been used to solve for the acoustic pressure. The method is applied to the case of scattering from and propagating through a 2‐D infinitely long cylinder with the properties of fat tissue encapsulating a cyst. It is found that ignoring the heterogeneity in the medium can lead to significant error in the propagated/scattered field. © 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007     

我国证券市场传染性的实证研究

本文利用计量经济学方法分别就上海、深圳A、B股市场关联性与因果关系进行了定量分析,结论是:B股市场向境内居民的开放,使得我国股票市场的联系更为紧密,传染性更明显,且大致说来,一个股票市场对另一个股票市场的作用,一般在2至4个交易日就可达到较大的程度。     

Multivariate causality tests with simulation and application

This paper extends the test established by Hiemstra and Jones (1994) to develop a nonlinear causality test in a multivariate setting. A Monte Carlo simulation is conducted to demonstrate the superiority of our proposed multivariate test over its bivariate counterpart. In addition, we illustrate the applicability of our proposed test for analyzing the relationships among different Chinese stock market indices.