负地性

We give several sufficient conditions of NA and NSD properties of random variables, compare the closeness of distribution functions of order statistics between NA and independent rv's, investigate properties of NSD defined by supermodular functions, study the dependence structure of stationary Markov process and order statistics and their spacings from two samples, establish stochastic comparisons of order statistics of heterogeneous rv's in the hazard rate and the reversed hazard rate orders, and give the first analytic proof of the closure property of the up shifted likelihood ratio order under convolution.

给出判定一组随机变量NA性质的几个充分条件，并给出NA和独立随机变量的次序统计量之间"贴近性"的比较，系统地研究基于特殊函数类所定义的NSD负相依概念，给出一些判别NSD性质的结构定理和一些有用概率不等式。系统研究平稳马氏过程的相依结构。研究两样本次序统计量及其问题隔的相依结构。在失效率、反向失效率序和似然序意义下给出非齐次随机变量次序统计量的比较。给出上漂移似然序卷积封闭性的第一个解析证明。

Unfortunately, it has been shownthat these methods are not suitable to study about chemical bonds due to not involvingchemical bonds. In order to consider chemical bonds obviously, we have proposed an atom-bondelectronegativity equalization model on the basis of density-functionaltheory and electronegativity equalization principle. The main contents of our atom-bond electronegativity equalization model contain:(1)Considering the fact that there are varies of chemical bonds in molecules andpartitioning the molecular electron density as summations of atomic electron densitiesand chemical bond's electron densities, we obtained the basic equations of atom-bondelectronegativity equalization model: the expression of the total energy 〓, theexpression of the atom electronegativity 〓 and the expression of the bondelectronegativity 〓.

为了明确地考虑和处理分子中存在的化学键，以便能够更好地描述体系中的电荷分布进而准确地描述分子体系中的有关物理化学性质，尤其是与化学键有关的物理化学性质，我们在密度泛函理论和电负性均衡原理基础上提出了原子-键电负性均衡模型，原子-键电负性均衡模型的主要内容是：(1)考虑到分子体系中存在各种化学键这个事实，将分子空间看成是由原子区和化学键区组成的，将分子的单电子密度表达成为分子中各组成原子的单电子密度和各化学键的单电子密度的加和，从而得到了原子-键电负性均衡模型的基本方程：分子体系总能量〓和分子中原子电负性〓和化学键电负性〓表达式。

Zhan has determined the maximum and minimum numbers of positive entries of imprimitive irreducible nonnegative matrices with a given imprimitivity index. In this paper, we prove that if a positive integer is between the maximum and minimum numbers, then there exists an irreducible nonnegative matrix A with the given imprimitivity index and with the given number of positive entries.

非负矩阵是矩阵论中研究比较活跃的领域，不可约非负矩阵是比较重要的非负矩阵，本文分两部分，一部分主要在詹兴致教授的研究基础上研究了给定非本原性指标的不可约非负矩阵中非零元个数的连续性，肯定地回答了詹兴致提出的一个自然的问题。

Since Leptokurtosis, skewness and fat-tail are always used to depict market risk, this paper introduces the improved Laplace distribution to risk management of stock portfolio. Empirical results show, improved Laplace distribution and asymmetric Laplace distribution are similar for estimating Leptokurtosis, while improved Laplace distribution is better for estimating skewness.In order to analyze the correlation between return distribution and volatility, the thesis uses ARCH-M Models to simulate the return series of China's Stock Market and developed markets ao as to discover the relation between investment return and time-varying risk.

对尖峰、厚尾、偏态的刻画有助于正确估计市场风险，本文将改进型Laplace分布引入到股票组合的风险管理中，实证结果发现，改进型Laplace分布和非对称Laplace分布对尖峰、厚尾的刻画效果接近；而非对称Laplace分布对负偏性考察不足，改进型Laplace分布的拟合结果能够准确地反映股指收益的负偏态，这也正是改进型Laplace分布相对于传统的非对称Laplace分布的优势所在。

The chilling tolerance appraisal of melon seed could be used germination index and vigor index at 18 , but the latter was more correct and liable, whereas germination percentage could not be used to identify chilling tolerance of seed.

3利用电导法测定了甜瓜幼苗叶片电导百分率。7℃时的电导百分率与品种的耐冷性呈极显著负相关，且品种间差异十分明显，因而能较好地鉴定甜瓜苗期的耐冷性强弱。

In chapter5, the serial properties of numerical range of operator polynomial are put firstly. Secondly, the relation between numerical range of operator polynomial and n-numerical range are considered. Thirdly, in the light of matrix norm, matrix singular value, the regions and bounds of numerical range and spectrum of operator polynomial are dicussed carefully.

第五章研究了算子多项式数值域的性质、算子多项式数值域与n-次数值域的关系，特别地利用矩阵范数、矩阵的奇异值、非负矩阵的理论、友矩阵为工具，给出了算子多项式数值域及谱的范围全面刻画，并深刻地研究了算子线性束的正则性的等价条件及谱分布。

Most importantly, our team are famous for much research on ecology, physiology,molecular phylogenesis of bats at home and abroad, we have gained much originative result in this field, and we firstly found and studied the third piscivorous bat, Myotis ricketti.We provide evidence that the species Myotis ricketti is piscivorous, and close negative relationships were found firstly within Rhinolophidae and Hipposideridae between call frequency and ear length. Some species of taxology status in rhinolophidae were studied by molecular phylogenesis; phylogenesis relationship between rhinolophidae and hipposideridae and different populations of miniopterus schreibersii were also studied; we also studied Social structure of Tylonycteris pachypusa and T. robustula and the isolating mechanisms of ecological niches.

在蝙蝠生态、生理、和分子系统进化领域完成了大量研究，奠定了本项目组在此领域中的国际地位，首次在国际上证实性发现并系统研究了世界上第3种食鱼蝙蝠--大足鼠耳蝠；首次提出菊头蝠科蝙蝠回声定位叫声频率与耳长负相关；利用分子系统学研究方法澄清菊头蝠科内一些种的分类地位，菊头蝠科和蹄蝠科的关系，以及普通长翼蝠种群间的系统进化关系；系统地研究了扁颅蝠属仅有两个姐妹种的社会组织结构和生态位分化。

And such methods V/m ratio t-test, negative binomial parameter, index of dispersion, Cassie index, index of clumping, index of mean crowing and index of patchiness are employed to analyse various dominant populations of Heptacodium miconioides community in the Tiantai Mountain in Zhejiang province and distributive patterns of Heptacodium miconioides community in different quadrats, and this paper also examines the intensity of Heptacodium miconioides population in different quadrats by means of stand classes.

摘 要 以浙江省天台山七子花群落为研究对象，采用相邻格子样方法取样数据，应用方差／均值比的t检验法、负二项参数、扩散型指数、Cassie指标、丛生指标、平均拥挤指数和聚块性指数等方法，分析了七子花群落各优势种群以及七子花种群在各样地中的分布格局，并分立木级对七子花种群在不同样地内的集群强度进行了测定。

Seen from clinical effect, haemodynamics and general condition both better in rats treated with dexamethasone than rats treated with saline. We had a presumption on these grounds that the sum of negativity myodynamia generated byβ3-AR up-regulation andα1-AR down-regulation possibly less than positive myodynamia generated byβ1-AR up-regulation. 5 For patients with DCHF, adding prednisone to the usual care resulted in significant relief of the congestive symptoms, which was accompanied with a potent diuresis with time and an improvement in renal function.

从临床效果来看，地塞米松治疗的心衰大鼠在血流动力学及一般状况上，都明显优于注射生理盐水的心衰大鼠，据此推测，β3受体上调和α1受体下调产生的负性肌力之和可能弱于β1受体上调产生的正性肌力。5对于失代偿的充血性心力衰竭病人，在心衰常规治疗基础上加用强的松这种糖皮质激素能显著缓解充血症状，并伴随着强有力的利尿和改善肾功能的作用。

Based on density functional theory and electronegativity equalization principle,applying an atom-bond electronegativity equalization σπ model,using a separated program,we calculated the charge distributions and dipole moments of guanine tautomers.

以密度泛函和电负性均衡原理为基础发展的原子-键电负性均衡方法的σπ模型。并结合自编程序，计算了鸟嘌呤五种异构体的电荷分布和偶极矩，计算结果表明，所计算出的电荷分布可以和从头算结果很好地关联。所计算的偶极矩与其它从头计算方法和力场方法相比总体趋势相同，进一步说明了ABEEMσπ模型的合理性

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。