高聚物双流体配位模型状态方程的简化

对高聚物以流体配位模型状态方程进行了简化，忽略了其中的Ｑ项，以简化的状态方程对４２个纯高聚物（聚丙烯、聚苯乙烯、聚异丁烯和聚丁烯－１），２种纯溶剂（苯，环己烷）和２个高聚物／溶剂混合系（聚异丁烯／苯和聚异丁烯／环己烷）进行关联，结果表明，简化的状态方程与原方程同样具有很好的关联精度和温度适用性。     

Equivalent measures of dependence

The maximal correlation between a pair of σ-fields $\text{A}$ and $\text{B}$ becomes arbitrarily small as sup{|P(A ? B) ? P(A) P(B)|/[P(A) P(B)]^1/2, A ∈ $\text{A}$, B ∈ $\text{B}$, P(A) > 0, P(B) > 0} becomes sufficiently small.     

The defect diffusion model, scaling, EV*/H* and monomer volume and correlation lengths for glass-formers

Four topics are treated within the framework of the defect diffusion model (DDM). First, it is shown how the relationship between E_V*/H* (ratio of the apparent isochoric activation energy to the isobaric activation enthalpy) and monomer volume for polymers that has been pointed out by Floudas and co-workers [G. Floudas, K. Mpoukouvalas and P. Papadopoulos, J. Chem. Phys. 124 (2006) 074905] is predicted. Next, it is shown that in the DDM, scaling arises because the critical temperature can be represented approximately by a power law. Consequently, in the DDM scaling is always approximate and significant departures from scaling, as is observed in the case of hydrogen bonded materials for example, are matters of degree. It is also shown how the connection of scaling with E_V*/H* is a natural consequence of the DDM. Finally, DDM calculations of the defect correlation length are carried out and compared with experimental dynamical correlation lengths measured using the 4D3CP solid state NMR method.     

Statistical characterization of the pore space of random systems of hard spheres

An improved statistical characterization of disordered structures such as metallic glasses, random porous media, or granular matter is presented. Suitable structure models follow the idea of dense random packed spheres, where the spheres represent atoms and particles in the case of metallic glasses and porous or granular matter, respectively. The geometry of the empty space between the atoms or particles is described by means of the already otherwise successful concept of so-called contact distributions. Their exact mathematical forms are unknown for hard sphere systems. Knowledge on these is obtained by means of Monte Carlo simulations of the structure models. The numerical results are approximated by simple and general mathematical expressions, with parameters that can be easily determined. These may serve as additional tools for the structural characterization of disordered matter, including systems of partly penetrable spheres.     

3D graphical representation of protein sequences and their statistical characterization

Based on three physicochemical properties of amino acid side chains, we proposed a novel unique 3D graphical representation of protein sequences. Then, we constructed two vectors of three components as mathematical objects to characterize protein sequences numerically. The similarity/dissimilarity analysis among nine ND5 protein sequences proved the utility of our approach. A correlation and significance analysis have been provided to compare our results and the sequence homology.     

On the occurrence of the sine kernel in connection with the shifted moments of the Riemann zeta function

We point out an interesting occurrence of the sine kernel in connection with the shifted moments of the Riemann zeta function along the critical line. We discuss rigorous results in this direction for the shifted second moment and for the shifted fourth moment. Furthermore, we conjecture that the sine kernel also occurs in connection with the higher (even) shifted moments and show that this conjecture is closely related to a recent conjecture by Conrey, Farmer, Keating, Rubinstein, and Snaith (2003, 2005) [CFKRS1] and [CFKRS2].     

Multi-layer model of correlated energy prices

In this article we develop an extension of the affine jump-diffusion modeling framework and use it to build an intuitive and tractable model of an energy price complex. The development is motivated by the need to model prices of electricity while capturing their dependence on the price of other energy commodities. Such a model is essential for valuing a range of typical derivatives traded in the electricity markets: cross-commodity spread options, cross-location spread options, fuel-switching powerplants, etc. We give an approximate pricing method for these derivatives together with precise error bound estimates.     

Fuzzy decision-making method based on the weighted correlation coefficient under intuitionistic fuzzy environment

A multicriteria fuzzy decision-making method based on weighted correlation coefficients using entropy weights is proposed under intuitionistic fuzzy environment for some situations where the information about criteria weights for alternatives is completely unknown. To determine the entropy weights with respect to a set of criteria represented by intuitionistic fuzzy sets (IFSs), we establish an entropy weight model, which can be used to get the criteria weights, and then propose an evaluation formula of weighted correlation coefficient between an alternative and the ideal alternative. The alternatives can be ranked and the most desirable one(s) can be selected according to the weighted correlation coefficients. Finally, two illustrative examples demonstrate the practicality and effectiveness of the proposed method.     

我国农村居民消费现状及影响因素分析

我国经济虽然实现了高速增长,但城乡居民消费差距不仅没有缩小,反而在继续扩大,由占人口绝对多数的农村居民的消费水平过低所直接导致的我国消费需求不足已成为目前我国宏观经济中最突出的矛盾。本文在农村居民消费结构的基础上,分析影响居民消费的其他原因,以及这些因素与消费的相关程度,建立回归模型,并采用2007年中国农村居民的收入消费等统计资料,对消费状况进行实证分析。最后本文针对我国农村居民现实的消费状况提出针对性的建议。