长江经济带生态效率时空格局演化及影响因素研究

文章基于108个城市2004-2014年市级面板数据测度了长江经济带城市生态效率的时空演变格局,综合而言,长江经济带生态效率水平呈现出波动上升态势,长江流域城市生态效率分化特征明显,湖南、湖北和四川等长江上游城市生态效率较高,长江上、中、下游地区城市生态效率依次递减.对生态效率的影响因素研究表明,科技创新显著地提高了长江经济带的生态效率,经济快速增长降低了城市生态效率,意味着转变经济增长方式、加快科技创新是提高城市生态效率的有效途径.研究还发现,产业结构偏离度有利于提高城市生态效率,而产业升级抑制了城市生态效率的增长,意味着产业升级并不是提高城市生态效率的捷径.     

疾驰的哀鸣:论张枣诗歌中的声音与抒情表达

诗人张枣一生仅仅创作了百余首诗歌,但在这些为数不多的作品中,关于传统,他始终有着一种相对明晰的态度。本文选择以声音的视角切入,将通过句式、停顿、词的选择等包孕在情感与意象中的内在化节奏展开,从而在声音传统中去洞悉张枣的诗歌所彰显出的哀鸣与急促等情感特征。     

Asymptotic approximations to the distribution of Kendall's sample τ

This paper provides a saddlepoint approximation to the distribution of the sample version of Kendall's τ, which is a measure of association between two samples. The saddlepoint approximation is compared with the Edgeworth and the normal approximations, and with the bootstrap resampling distribution. A numerical study shows that with small sample sizes the saddlepoint approximation outperforms both the normal and the Edgeworth approximations. This paper gives also an analytical comparison between approximated and exact cumulants of the sample Kendall's τ when the two samples are independent.     

“（是）……的”类句式已然义的层次性分析——以“S（是）AV（O）的”句式为例

以学界广为关注的“S（是）AV（（））的”句式为例，重点分析“（是）……的”类句式在语境、词汇和句法三个层面所显示的不同已然义特征，并以此为基础对国内外关于已然义“（是）……的”类句式的相关研究进行简要的评价。     

三河古镇空间肌理与情态浅析

以历史文化名镇三河古镇为研究对象，以历史资料与现场调研为依据，从自然历史形成因素出发，对三河古镇空间肌理进行分析，探讨古镇选址与布局、街巷格局、建筑风貌以及人文情态的基本特征，并针对三河古镇当前存在的空间氛围破坏、传统意境流失等问题提出若干对策，为恢复古镇昔日活力，更好地建设和营造现代人居环境提供一定的启发与借鉴。     

A general approximation to quantiles

For many continuous distributions, a closed-form expression for their quantiles does not exist. Numerical approximations for their quantiles are developed on a distribution-by-distribution basis. This work develops a general approximation for quantiles using the Taylor expansion. Our method only requires that the distribution has a continuous probability density function and its derivatives can be derived to a certain order (usually 3 or 4). We demonstrate our unified approach by approximating the quantiles of the normal, exponential, and chi-square distributions. The approximation works well for these distributions.     

Sums of powers of binomial coefficients

An asymptotic series for sums of powers of binomial coefficients is derived, the general term being defined and usable with a computer symbolic language. Sums of squares of coefficients in the symmetric case are shown to have a link with classical moment problems, but this property breaks down for cubes and higher powers. Problems of remainders for the asymptotic series are mentioned. Using the reflection formula for I'(.), a continuous form for a binomial function is set up, and this becomes oscillatory outstde the usual range. A new contmued fraction emerges for the logarithm of an adjusted sum of binomial squares. The note is a contribution to the problem of the interpretation of asymptotic series and processes for their convergence acceleration.     

Cumulants of random sum distributions

Consider a random variable S being the sum of a number N of independent and identically distributed random variables X_j (j = 1, 2, ...) where the number N is itself a non-negative integer-valued random variable independent of the X_j An explicit expression of the r-th cumulant of S is given in terms of the cumulants of N and X_j, Asymptotic properties of the distribution of S are also discussed.     

写作表述的三级范式

写作表述在文句、层次和篇章等三个层级上都有一定的范式。表述范式在不同基本文体的层次范式之间、篇章范式之间,以及篇章范式和层次范式之间,虽然各有不同,但也有共同之处。这些表述范式分别都是其同类相仿的写作表述模式构造,能为写作者实施写作表述提供可以借鉴的基本经验。