离散问题

Spectral methods and the classical Crank-Nicolson scheme are applied to deduce the full discrete system for the continuous model, then the variational adjoint assimilation approach is used to derive the gradient and the corresponding adjoint system.

从这个全离散问题出发，结合全局或局部已知的观测数据，分别构造梯度下降算法求解相应的最优化问题。我们分析了采用不同方法计算梯度所需的代价，另外，还给出一种选择最优迭代步长的算法。

At present, the particle swarm optimization algorithm in a row on the issue has very broad applications, but in the discrete optimization problem is still trying to stage.

详细说明：：目前，粒子群算法在连续问题优化上的应用已经很广泛，然而在离散问题优化方面仍处在尝试阶段。

By defining time span combination, the continuous varying parameter optimization problem is transformed to discrete multi-parameter optimization problem and model is constructed.

引入时段组合的概念，将连续问题转化成离散问题，将变参数优化问题转化成多参数优化问题，建立了相应的数学模型，并给出简化求解的方法。

Methods in discrete mathematics, such as finite difference equation, simulation, coding, etc. The related cases are "Mortgage loan and other financial problems","Simulation of inventory problem","Adding cipher and extricating for Hill code", and "Input-output analysis".

某些离散问题的数学方法(差分方程问题，仿真方法，密码学等)，这部分内容相应的教学案例是"个人住房抵押贷款与其他金融问题"，"库存问题的仿真方法"，"Hill密码的加密、解密和破译"和"投入产出分析"等

First, we consider an iterative algorithm of Jacobi type and the corresponding domain decomposition algorithm for a approximate quasivariational inequality system of the Hamilton- Jacobi- Bellman equation and the corresponding convergence problem.

本文研究了逼近Hamilton-Jacobi-Bellman方程的拟变分不等式组的离散问题的Jacobi型迭代算法和Jacobi型区域分解法及其收敛性问题。

We introduce the iterative method of Jacobi type to solve the discrete problem of the quasivariational inequality system. A new proof for the monotone convergence of the iterative method is given under appropriate conditions.

我们首先介绍求解Hamilton-Jacobi-Bellman方程的近似拟变分不等式组离散问题的一类Jacobi型迭代算法，在一定假设条件下，对这类算法的单调收敛性给出了一个新的证明。

The Discrete Logarithm Problem was analyzed. Based on the discrete logarithm in the prime field, and combined with the elliptic curve DLP in the limited domain, a new digital signature was brought up.

分析了离散对数问题，以素数域上的离散对数为基础，同时结合有限域上的椭圆曲线离散对数问题，提出一种新的数字签名方案，其安全性建立在离散对数算法上。

In order to eliminate the effect of dimension,the two objective functions were regulated.The experiments on a mixed model assembly line show that the modified discrete PSO algorithm maintains the advantages of PSO algorithm and can solve the mixed model assembly line sequencing problem effectively and rapidly.

对实际混流装配线的仿真实验表明提出的改进微粒群优化算法可以直接应用于离散问题并保持了基本微粒群算法的优良性能，是一种性能较好的高效的混流装配线排序算法。

The analysis can be extended to the two , three and higher dimensional problems.

此分析可扩展到二维、三维或更高维，而且可以通过快速傅里叶变换来解决离散问题。

Some examples in other references are recomputed and both simulation results are compared.

通过对其它文献中仿真实例的计算和结果对比，表明该算法对求解0-1背包问题的有效性，这对差异演化算法解决其它离散问题会有些帮助。

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。