极大值原理

The existence and uniqueness of solution for population dynamics and the corresponding maximum principle are obtained by using Banach's fixed point theorem and the concept of normal cone.

第二节和第三节分别对具有年龄结构的竞争两种群和n种群扩散系统的最优收获问题进行了研究，获得了相应的极大值原理，以及两种群竞争系统最优控制问题解的存在唯一性。

Based on Pontryagin maximum principle,the lunar soft landing problem is transformed into a two-point boundary value problem in mathematics.

首先，从庞德里亚金极大值原理出发，将有限推力作用下月球软着陆问题转化为数学上的两点边值问题；在考虑边界条件及横截条件的前提下，将该两点边值问题转化为针对共轭变量初值和末时刻的优化问题；然后应用非线性规划方法求解所形成的参数优化问题。

In this paper,an optimum trajectory from perilune to lunar surface is derived in terms of Pontryagin's maximum principle,which is an open-loop way.Then,an optimal nonlinear control law based on an fuzzy neural network is presented,on the basis of the optimum trajectory,due to the nonlinear mapping function of the fuzzy neural network,which is a closed-loop way.

本文根据终端着陆条件和性能指标，以由Pontryagin's极大值原理得出从近月点到月球表面的最优着陆轨迹为基础，给出一种基于模糊神经网络的非线性最优控制策略，使被控系统能够通过模糊神经网络的非线性映射能力实现某种最优的闭环制导控制。

Basically,an optimal nonlinear control law based on an artificial neural network is presented,on the basis of the optimum trajectory from perilune to lunar surface in terms of Pontryagin's maximum principle according to the terminal boundary conditions and performance index.

其主要内容是，根据终端着陆条件和性能指标，以由庞氏极大值原理得出从近月点到月面的最优着陆轨迹为基础，给出一种基于人工神经元网络的非线性最优控制策略，使被控系统能通过神经网络对非线性的映射能力实现某种最优的非线性控制。

On this basis, anoptimization algorithm library named OPTLIB is formed. The study of dynamic optimization theory is followed. To solve the problem of thecoupling of the static and the dynamic parameters of the flying vehicle design, some auxiliaryvariables are introduced to deal with them together. Then the calculus of variation is adoptedand augment form of Pontryagin's Maximum Principle is derived.

研究了飞行器设计中的典型动态优化问题——轨迹优化问题及算法，针对飞行器设计中的静态参数和动态参数互相耦合的问题，引入辅助变量将静态参数和动态参数统一处理，在此基础上用变分法推导了极大值原理的增广形式，证明了单独的静态或动态最优并不等于总体最优。

Based on Pontryagin maximum principle, the lunar soft landing problem is transformed into a two-point boundary value problem in mathematics. In consideration of the bound condition and transversality condition, the resulted two-point boundary value problem is converted into a parameter optimization problem aiming at the initial values of conjugate variables and the terminal time, then it is solved by the nonlinear programming.

首先，从庞德里亚金极大值原理出发，将有限推力作用下月球软着陆问题转化为数学上的两点边值问题；在考虑边界条件及横截条件的前提下，将该两点边值问题转化为针对共轭变量初值和末时刻的优化问题；然后应用非线性规划方法求解所形成的参数优化问题。

Taking range as the performance function, considering end velocity, height and trajectory slope angle constraints, the optimal glide trajectory was solved by maximum principle of Pontryagin and conjugate-gradient method.

建立了滑翔弹道模型，以射程为指标函数，考虑终端速度、高度和弹道倾角约束，采用庞特里亚金极大值原理和共轭梯度法求出控制变量有约束的最优滑翔弹道，简要分析了滑翔增程机理。

Firstly the dimensionless planar motion model of SGKW was established;then the optimal control problem of shortest time coplanar hit orbit was transformed into two-point boundary value problem by means of Pontryagin maximum principle .

首先建立了SGKW的无量纲化平面运动模型，然后利用庞特里亚金极大值原理将时间最短共面打击轨道的最优控制问题转化为两点边值问题。

This OCVC problem was converted to a typical two-point boundary-value problem according to Pontryagin maximum value principle, and this TPBVP was a first order optimality condition which could be solved by Radau collocation method.

根据Pontryagin极大值原理建立该协调电压控制问题的1阶最优性条件，该条件是一个典型的两点边值问题。在此基础上采用拉道排列法求解这个两点边值问题。

According to the requirement of a minimum-fuel-consumption, a method of coplanar hit orbit optimization design for SGKW was studied. The dimensionless planar motion model of SGKW was founded, and the optimal control problem of minimum-fuel-consumption coplanar hit orbit was derived into two-point-boundary-value problem according to Pontryagin maximum principle.

针对燃料最省要求，研究了SGKW共面打击轨道优化设计方法，建立了SGKW的无量纲化平面运动模型，利用庞特里亚金极大值原理将燃料最省共面打击轨道的最优控制问题转化为两点边值问题。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。