存在的性质

It mainly studies the choice of mode for competitive tender offer under different bidders' type.

首先，借鉴Perry，Wolfstetter和Zamir（2000）的有关理论，从基于两阶段密封价格投标的竞争性要约收购过程开始，讨论了其中的一些性质，结果表明，同质收购者前提下该过程不但能够获得和基于英式竞价的竞争性要约收购过程相同的期望收益，还能够克服后者存在的一些问题；随后，在异质收购者内生参与条件下就基于英式竞价和密封投标的竞争性要约收购过程进行了比较研究，得到了不同方式下收购结果的特征；最后，针对异质收购者不同知情程度的情况研究了竞争性要约收购方式的选择问题，借鉴Povel和Singh（2004）提出的机制，得到了具备"胡萝卜加大棒"性质的序贯出售过程是这种情况下控股股东的最优选择。

The first part presents develops of predator-prey systems and gives the model that is investigated in our paper; Chapter 2 presents the results on boundedness of solutions and permanence of system; In chapter 3, we explicitly derive a domain of attraction for the positive equilibrium of system by using Liapunov method; The local stability and the conditions that Hopf bifurcation occurs are obtained in chapter 4; In chapter 5, some explicit fomulae of the direction of Hopf bifurcation and the stability of bifurcating periodic solutions on the center manifold are determined,using normal form and center manifold introduced by Hassard et al; In chapter 6, some numerical simulations are performed to illustrate the analytical results found; Our paper ends with a brief conclusion.

全文共分七章，第1章对捕食-食饵系统的发展背景做了介绍并给出了本文研究的模型；第2章讨论了系统的保持性和解的有界性；第3章研究正平衡点的全局性质，对正平衡点的吸引域进行了精确估计；第4章研究了系统的正平衡点的局部稳定性和Hopf分支存在的条件；第5章利用规范型和中心流形定理得到了一个决定Hopf分支方向、分支周期解的稳定性及其他性质的精确公式；第6章对一个具体模型进行了数值模拟；第7章对全文进行了总结。

Further, with the help of Riccati equations, an infinite number of conservation laws for the solton hierarchy are deduced. For the sake of simplicity, taking the general TD hierarchy as an illustrative example, we prove that its 2×2 Lenard pair of operators forms a Hamiltonian pair. Thus the isospectral evolution TD hierarchy is the general Hamiltonian system and possesses the Bi-Hamiltonian structures and Multi-Hamiltonian structures. By using the method of derivation of functional under some constraint condition, a complete one-to-one correspondence between the Hamiltonian functions of the hierarchy and its conservation density functions can be built. These results can also be applied to the isospectral evolution soliton hierarchy of this paper. Finally, there's a gauge transformation between the spectral problem of this paper and the AKNS system. Moreover, the potentials in these spectral problems satisfy the general Miura transformation, the corresponding relationship between the two soliton hierarchies is also given.

进一步本文还通过特征函数的组合关系所满足的Riccati方程，得到了该等谱方程族的无穷多个守恒律；为简便起见，本文以广义TD族为例，由它的2×2 Lenard算子对的性质证明了此算子对为Hamilton算子对，这说明广义TD族是广义Hamilton系统且具有Bi-Hamilton结构和Multi-Hamilton结构；进而利用它的依赖于谱参数的一般守恒密度的积分在约束条件下求泛函导数的方法，得到了广义TD族的Hamilton函数与守恒密度之间的对应关系，这些性质对于由本文提出的2×2谱问题所导出的等谱孤子族仍成立；另外此谱问题与AKNS系统存在着规范变换，位势之间有广义Miura变换，而孤子方程之间也满足一定的等价关系。

Secondly, in this part, we will introduce the notation of average geodesic curvature for curves in the hyperbolic plane, and investigate the relationship between the embeddedness of the curve and its average geodesic curvature. Finally, we will employ the Minkowskis support function to construct a new kind of non-circular smooth constant breadth curves in order to attack some open problems on the constant width curves for example, whether there is a non-circular polynomial curve of constant width, etc.

其次，对双曲平面上的曲线引入平均测地曲率的概念，并讨论双曲平面上凸曲线的嵌入性与它的平均测地曲率之间的关系，其目的是为了将双曲平面上曲线的性质与欧氏平面中曲线的性质作一些对比；最后，我们利用Minkowski支撑函数构造了一类新的非圆的光滑常宽曲线，其目的是想回答有关常宽曲线的一些未解决问题如是否存在非圆的多项式常宽曲线？

Here, we will give an independent proof of the existence for inequality (2.1.3), and by the way, give an estimate on the width of the bi-enclosing annulus of closed convex curves in the plane. Secondly, in this part, we will introduce the notation of average geodesic curvature for curves in the hyperbolic plane, and investigate the relationship between the embeddedness of the curve and its average geodesic curvature.

其次，对双曲平面上的曲线引入平均测地曲率的概念，并讨论双曲平面上凸曲线的嵌入性与它的平均测地曲率之间的关系，其目的是为了将双曲平(来源：ABC论84文网www.abclunwen.com)面上曲线的性质与欧氏平面中曲线的性质作一些对比；最后，我们利用Minkowski支撑函数构造了一类新的非圆的光滑常宽曲线，其目的是想回答有关常宽曲线的一些未解决问题如是否存在非圆的多项式常宽曲线？

From these researches as above, this paper found a new method to analysis salty soil road engineering properties by phase equilibrium theory, which provides a new angle of analysis on salty soil properties, experiment and engineering practice in these ways as follows:(1) Analysis the disadvantage of traditional salty soil experiment;(2) Analysis the disadvantage of current salty soil definition by phase equilibrium theory, and gives the chart of distinguish salty soil by the condition of hydrography and climate change;(3) Analysis the mechanics of subgrade frost boiling based on the change rule of liquid content;(4) Based on the change rule of ingredients content and volume in salty soil, analysis the mechanics of subgrade salt heaving and the restraining method by adding sodium chloride.

通过以上研究，本文初步建立了以相平衡理论为核心的盐渍土路用工程性质分析方法，该方法对盐渍土工程性质的理论分析、试验研究以及工程实践提供了新的研究思路与方法，具体体现在：(1)分析了传统的盐渍土试验存在的缺陷；(2)分析了现行盐渍土定义的不足，并以相平衡理论为基础，结合水文、气候条件的变化给出了判别盐渍土的诺谟图；(3)分析了盐渍土盐溶液含量的变化规律，并从盐渍土含液量变化规律出发，分析了盐渍土路基较非盐渍土路基翻浆严重的机理；(4)分析了盐渍土各固相含量及其体积的相变规律，并在此基础上分析盐渍土路基的盐胀机理，以及采用添加氯化钠来抑止硫酸盐盐渍土的盐胀机理

Content abstract: The article from the job category, the investment originated, the operational mechanism three aspects to differentiate and to limit the public welfare and the commercial character two kind of heterogeneity geological work; Has analyzed the geology surveying work reform background, has been clear about the reform guiding principle; Has analyzed under the traditional system the geology surveying work existence malpractice, reviewed the former reform measure; Based on this, the major issue three aspects which from the organization, the operational mechanism and must solve establishes the land resources big investigation the new system, the new mechanism; Finally, the author believed that what the deepened commercial character geology work reform is most essential cultivates the geological minerals Investment company, namely, on the one hand expanded geology investigation investment origin, on the other hand the cultivation geology investigation's subject of investment, and must strive for stock going on the market positively, widely uses the social fund, the reform commercial character geology work operational mechanism.

内容摘要：文章从工作性质、投资来源、运行机制三个方面区分和界定了公益性和商业性两类不同性质的地质工作；分析了地质勘查工作改革的背景，明确了改革的指导思想；分析了传统体制下地质勘查工作存在的弊端，回顾了以往的改革措施；在此基础上，从机构、运行机制和必须解决的重大问题三个方面建立国土资源大调查的新体制、新机制；最后，作者认为，深化商业性地质工作改革最关键的是培育地质矿产投资公司，即，一方面扩大地质勘查的投资来源，另一方面培育地质勘查的投资主体，并要积极争取股份上市，广泛利用社会资金，改革商业性地质工作的运行机制。

The ideas we have of these they acknowledge not to be the resemblances of anything existing without the mind, or unperceived, but they will haveour ideas of the primary qualities to be patterns or images of things which exist without the mind, in an unthinking substance which they call "matter".

我们对后一种性质所有的观念，他们承认不是与心外事物相似的肖像。不过他们却以为人心对原始性质所有的观念是心外存在的事物的摹本和影象，而且他们以为那些事物是在所谓&物质&的一种不能思想的实体以内存在的。

3D effect is analyzed and the average velocity of wave propagating in the pile, which mainly influences inverse interpretation, is discussed. Finally, the theory results are verified by model experiment. It is shown that 3D results have the same phase with ID results. The pile radius, the duration of impulse, the ratio of hammer radius to pile radius and shear velocity of the soil around the pile have influences on 3D effect. The best position of receiver is 0.55R from the pile center. The average velocity of wave propagating in the pile reduces due to transversal inertia effect and 3D effect.

结果表明：三维曲线与一维结果在相位特征上一致；波场图直观地反映了波在桩中的传播规律；三维效应与桩径、激振脉冲宽度、相对激振半径及桩周土剪切波速有关；传感器放在0.55R处可以得到干扰较小的信号；三维效应和横向惯性效应的存在会使桩中的波速减小，土的性质对波速影响不大；反演精度与缺陷的性质、激振条件有关。

Different cells,cell density and cell shape lead to comparatively great difference in wood properties and physical mechanical properties, change of wood cells affects change of wood properties including wood quality,wood property and all other aspects,and wood properties decide economic value and directly affect manufacturing and utilization of wood,therefore,the research and analysis on wood cell structure become especially important.

由于树木生长不均匀，使各种树木的木材构造具有多样性，不同细胞体、细胞密度和细胞形状导致了木材材性和物理力学性能存在较大差异，木材细胞的变化影响着木材性质的变化，木材的性质又决定木材经济价值，并直接影响木材的加工和利用，由此对木材细胞结构分析研究就变得尤为重要。

I am sure after a few weeks of adaptation and familiarization I will have no difficulty in functioning on a daily basis in an English speaking society or in participating fully in graduate studies.

在大学的三年的学习生活不仅给予我自身的充实，更重要的是磨练和培养了我较强的自觉能力和严谨，踏实的作风以及不怕困难的精神，对未来充满了信心！

As the first volcanoes erupted, one of the gases that bellowed out was steam.

在第一批火山喷发时，喷出的气体之一就是水蒸汽。