比较函数

This system is permanent by comparative principle and globally asymptotically stable through constructing a Liapunov function; for the periodic case, the research has obtained conditions for existence, uniqueness and stability of a positive periodic solution.

利用比较原理研究了系统的持久性，通过构造Liapunov函数证明了系统的全局渐近稳定性，在假设系统为周期系统的条件下得到了正周期解的存在唯一性和全局渐近稳定的充分条件。

Furthermore, when the system is a periodic system, sufficient conditions are obtained that guarantee the existence, uniqueness and global attractivity of the positive periodic solution by applying the Brouwer fixed theorem and the method of constructing Liapunov function.

利用比较原理给出了系统一致持久性的充分条件；当系统是周期系统时，应用Brouwer不动点原理和构造Liapunov函数的方法给出其存在惟一且全局吸引的ω-周期正解的充分条件，并通过实例验证了文中定理条件的可实现性。

We examine both linear and sinc-based interpolation filters.

我们会比较线性和基於sinc函数的内插滤波器。

To study the performance of the algorithm, it is tested with a set of 5 benchmark functions and compared with the linear decrease weight particle swarm optimization algorithm.

为了评价其性能，选取了5个基准函数进行测试，并与惯性权重线性递减的粒子群优化算法作了比较。

Following are the main results of this thesis: Detailedly analyze some related schemes concerning group key management, We reconstruct a tree key management scheme, in comparison with Logical Key Hierarchy and One-way Function Tree schemes, we find that it has good performance of key storage, re-key communication costs and calculation of group manager.

本论文的主要研究成果如下：对目前存在的多播组密钥管理方案进行了详细的研究分析，提出了一种改进的树型管理方案，与逻辑密钥分层方案和单向函数树方案进行分析比较，它在密钥存储、密钥更新、通信量以及组管理者的计算量方面均有较好的性能。

In order to do the comparison, we called a lookup function.

为了做比较，我们称为查找函数。

In incorporation with Jilin province science and technology department item "Study of Industry Technological Advance Systemic Effect and Frame of Jilin Province industry Technology Incidence Establishment", about national interindustry incidence relation ,research is carried out in the paper as follows:On the base of national 1997 years input-output production table ,figures out direct consumption matrix of coefficients and matrices of middle input rate.

本文结合吉林省科学技术厅课题《产业技术进步系统效应及吉林省产业技术关联表编制框架研究》对我国的产业关联关系做了如下研究：在我国1997年投入产出表的数据基础上，计算出直接消耗系数矩阵及中间投入率矩阵，并将图分析法用于产业间关联关系的研究中；在计算完全消耗系数矩阵后，计算出各产业部门的感应度系数和影响力系数，并做了波及效果分析；本文经过对各种测算技术进步方法的比较，首次采用前沿生产函数中的数据包络分析方法分析投入产出模型中的产业间技术关联；机械设备制造业具有较高的物质关联性和技术关联性，同时波及效果显著，把含有高新技术的机械设备制造业作为主导产业发展，可以提高整个工业的技术装备水平。

In modeling heavy tails,we focus on multivariate t distributions and derive the moment generating function of the quadratic approximation.Then we use Fourier transform,Chebychev's Inequality and numerical technique inversion to approximate VaR value of portfolio,compared with Cornish-Fisher Expansions normal model and Delta-Normal model.

在推导出多个外汇期权的投资组合的二次近拟的矩母函数表达式基础上，本文使用傅里叶变换、切比雪夫不等式、数值转换计算求出投资组合的VaR的值，并和基于多元正态分布Cornish-Fisher模型以及基于Delta-正态模型计算所得的VaR值了进行比较。

V Roytburb′s results are generalized to inhomogeneous cases.Firstly,a monotone approximation to the flat function p is constructed,then the solutions of corresponding mudification system are estimated.

将V Roytburb的结果推广到非齐次情形，先对平坦函数p进行单调修正，再对修正方程组的解进行估计，最后比较原方程组的解和修正方程组解之间的关系。

Based on two newly - defined monotone restrictions for heuristic function h, the characteristic of monotone restrictions for algorithm BHAO is also investigated, and the comparison between two BHAO algorithms is also discussed.

本文还提出了两类新的启发式函数的单调限制概念，并据此研究了算法BHAO的单调限制性质，研究了两个BHAO算法间的比较性质。关键词广义

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。