有限模型

Onedimensional platelike dendritic model was built to describe the microsegregation during binary alloy solidification with finite solid backdiffusion and complete diffusion in the liquid.

建立了描述二元合金凝固的平面枝晶一维微观偏析数学模型，考虑溶质在固相中有限扩散，在液相中完全扩散。

A recovery system of manufacturing/remanufacturing for multiple products was investigated. Backlogging was granted with dynamic demands and returned rates. An optimal model was established by minimum total costs in a finite planning horizon, which was resolved by the Pontryagin's maximum principle.

针对多产品的生产／再生产混合系统的逆向物流库存控制问题，在假定允许缺货、需求和回收均为动态的情况下，建立有限时间域内总成本最小的优化模型。

Based on the data of posterior probability, we use the finite mixture modes to model the data.

2根据利用高斯混合判别分析得到的影像的后验概率，利用有限混合模型对数据进行建模。

The calculations of nucleus-nucleus potential are carried out in the framework of double folding model with M3Y-Reid and M3Y-Paris effective nucleon-nucleon interactions. The exchange part of the interaction, which is taken to be of finite range and the density dependence of NN interaction, is accounted for in the folding procedure. The results are used as the real part of the optical potential for heavy ion scattering.

用双折叠模型计算了核核碰撞的相互作用势，其中核子-核子相互作用势采用M3Y-Reid和M3Y-Paris形式，交换部分考虑了有限力程的密度依赖的核子-核子相互作用，程序用于重离子散射光学势实部的计算。

This paper first analyses and summarizes the ststus quo and evolution trend of encryption, some common used cryptograph are introduced, including the algorithms used in symmetric cryptosystem and asymmetirc cryptosystem. We describe the theory of each algorithms and compare the elliptic curve cryptosystem with the other two asymmetric cryptosystems to show the advantages of this algorithm. Second, the principle of ECC is discussed, including the math foundation of ECC, basic conception of elliptic curves, constructiong idea of ECC, operation on the elliptic curve and so on. Third, the current attacks of ECC were analyzed deeply, and an algorithm based on limited prime number field was constructed. We analyzed its realizability in theory, and implement it by using certain function of MIRACL software package. Latter half in this paper, the implementation model of a simple elliptic curve encryption system which based on GF has been introduced. The paper also put a deep analysis on the algorithm of point addition and point multiplication.

本文首先对密码技术的发展现状及其发展趋势进行了分析和综述，详细的介绍了私钥密码系统和公钥密码系统的发展，说明各种算法的原理和优缺点，并给出了一些典型的密码体制的简要分析，重点将椭圆曲线算法与其它几种公钥密码算法比较，说明椭圆曲线算法的优势；其次，探讨了椭圆曲线密码体制的原理，包括椭圆曲线密码的数学基础、基本概念、椭圆曲线密码体制的构造思想等问题；第三作者对椭圆曲线的攻击现状作了详细的分析，针对所使用的大素数域F_p，设计了素数域上安全椭圆曲线产生的算法，从理论上做了可实施性分析，从软件上做了具体实现；在本文的后半部分，提出了一个简单的基于有限素数域上的椭圆曲线加密方按算实现模型，并对SECES中设计的点加和点乘运算进行了深入分析。

Block probability of field network is analyzed by means of finite source queuing model combined with monte-carlo simulation.According to this concept,the formula of network throughput and average delay are obtained,and then an investigation is given for the effect of user number and variance of topology structure as well as capacity of date link.

采用有限信源排队模型及蒙特卡洛仿真相结合的方法分析了地域网的阻塞概率，并据此给出了网络吞吐量及延时性能的解析表达式，最后分析比较了不同用户规模，不同拓扑结构及链路容量对网络性能的影响。

Based on the system feedback archetype mode theory, the dissertation introduce the upper limit stepwise generation and elimination method of the system pullulate upper limit mode, construct the five upper limit archetype mode such as: market demand upper limit archetype mode, human resource upper limit archetype mode; fund upper limit archetype modes; technology innovation upper limit archetype mode; government support upper limit archetype mode ;By combining the five upper limit archetype mode ,we can attain a electronic information industry developmental pattern system upper limit archetype mode.

利用系统科学反馈基模分析理论，提出了系统成长上限模型上限逐步生成与消除法，通过构建江西电子信息产业市场需求成长上限子基模、人力资源不足成长上限子基模、政府支持有限成长上限子基模、资金不足成长上限子基模、创新能力不足成长上限子基模等5个基模，并对其做并运算，得到了江西电子信息产业系统成长上限基模，刻画了资金、市场、技术创新、人才与政府支持相互制约的关联关系。

Finite difference method for solving mathematical models, and through examples of well calculated and analyzed for heavy oil well electric heating rod pump production program designed to provide scientific basis.

有限差分法求解数学模型，并通过实例井计算分析，为稠油有杆泵电加热井生产方案设计提供科学依据。

During the iterations the trial step is truncated when necessary in order to keep the strict feasibility of the iteration points. It is shown that the LMTI approach and the STI approach have global convergence properties under some reasonable assumptions and will achieve local quadratic convergence rate under some even stronger conditions.

LMTI方法主要利用由有限内存BFGS公式的紧致形式获取的目标函数海色阵的近似矩阵构造信赖域问题模型并对其进行求解；而STI方法在构造的低维子空间上求信赖域子问题的解。

On the basis of comparison of several algorithms of the calculation of unstable resonator"s mode. Fast Fourier transform method is chosen in this paper. The model of multi-layer distribution of gain is established. Sampling granularity in real space used in FFT, quotient of guard band and distance between subsections are made certain respectively. The convergence criterion of root-mean-square of plural y which is the quotient of the optical field"s distributions separated by one pass is established. Under the circs of multi-kind of distribution of gain and different measurement of distortion, the output optical field distribution is calculated.

在比较了各种计算腔模方法的基础上，根据角谱传播理论，选择FFT算法，建立谐振腔内多层增益分布模型，分别确定了FFT算法的空间采样间隔、保护带系数和分段计算的距离，选取光场往返一次之比的均方根值收敛准则，计算多种增益分布、不同镜面变形时的谐振腔输出光场分布，同时计算该光场的远场分布和传输有限距离之后的分布。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。