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1.
极限:数学归纳法。数学归纳法的应用。数列的极限。函数的极限。根限的四则运算。函数的连续性。  相似文献   

2.
本文分别给出了Fuzzy矩阵存在广义{1,3}-逆、广义{1,4}-逆以及Mocre-Penrose广义逆Fuzzy矩阵的一些充要条件。又得到求上述广义逆Fuzzy矩阵的一些公式。主要的结果有:1.Fuzzy矩阵A的广义{1,3}-逆A^(1,3)(广义{1,4}-逆A^(1,4)的充要条件是Fuzzy关系方程X。A^T。A=(A。A^T。Y=A)有解。2.Fuzzy矩阵A的Mocre-Penrose广义逆A^+存在的充要条件是Fuzzy关系方程X。A^T。A=A,A。A^T。Y=A均有解。3.如果B、C分别的Fuzzy关系方程X。A^T。A=A,A。A^T。Y=A的一个解,那么A^ =A^T。C。B=C^T。AB^T=C^T。B。A^T。  相似文献   

3.
求部分分式待定常数的几个规则及简便求法   总被引:1,自引:0,他引:1  
有理函数分解为部分分式,往往要确定部分分式中的待定常数,常用的方法是用赋值法或比较法进行。下面讨论几个规则及简便的求法。假设为真分式,且P(x)与Q(x)无公共因子。从例1中可以看出,Ak(k=1,2,…,m)实际上等于中去掉Q(x)里的因子(x-a。),然后将x—a。代入后所得的值。利用这种方法进行心算可以很容易“读出”A。的值。如。。Th。。。。。Q;(。)。。,。,;。#。。#。。g证明用(x-a广乘(3)式的两端,得令x、a,两端取极限,注意到。即右端的极限为k!B。。,两端除以k!,即由(4)式知,当是一0时,有…  相似文献   

4.
这样推导好!     
高中《解析凡何》第74页例3推导过圆+,2二:2上一点M(x。,刀。)的切线方程的方i如下: 如图1,设切线的斜率为k,半径OM的:率为k,,因为圆的切线垂直于过切点的半径,于是左二一{· .矛 八“内比夕万 二L八 无二一与. :ll。经过M汽的切线方程是万一刀。一石、工一汪。’ 整理得:。x+y。、二二。’十、。’ 因为点M(二。,万。)在圆土,所以 场2十:li’0艺=尸. 所求切线方程是二。x+刀。万二:‘. 笔者认为教卞士中上述推导忽视了切线斜,不存在及为。的情况,犯了以偏概全的错误。事实上,当二。寺。或:lI。奔。时,推导圆的切线二程同上;当.:。=o,或…  相似文献   

5.
为使二重积分的计算简便,有时需要选择适当的变量替换。一般情况下.当积分区域为圆域或圆域的一部分时,用极坐标变换可以简化二重积分的计算,但这也不是绝对的。例如:求柱面x2+z2=a2与y2+z2=a2所围成立体的表面积。解法三西柱面所围成的立体如图1所示。由对称性知所求立体的表面积。其中y一J5n=i,R为圆域x’+z’<a’在第一象限的部分(见图2)。由于积分域为圆域的一部分,故可考虑利用极坐标。,。dx.v’、。/W仟RZ三二/*os叭Z一厂sin外二7一一7百一厂。丁】巨。。。。。smsz:::=。,-0。。。。。,。SWmp=vQ虾养…  相似文献   

6.
系统集成项目的工期风险传递算法及评价控制   总被引:4,自引:0,他引:4  
系统集成作为项目来管理越来越引起人们的关注。由于大的系统项目是由一个个具体的子项目集成的。且每个子项目都有其自身的特殊性和不确定性。为整个项目的实施带来了一定的困难和风险。而系统集成项目的工期是决定项目能否成功并获得预期收益的至关重要的因素。因此如何有效地进行工期风险评价控制成为一个非常关键的问题。基于此,本提出了一种风险传递算法。从而得出系统集成项目的总工期风险。并进一步从关键风险单元的识别人手进行工期风险的调整、优化和控制。其目的是为系统集成项目的成功实施提供有效的决策支持。  相似文献   

7.
扩散方程的随机Dirichlet问题   总被引:1,自引:0,他引:1  
令D。表示d+1维欧氏空间R。d的有界子集.旨在用概率方法利用时空布朗运动探讨D。上如下扩散方程的随机D irich let问题:12Δu(x。(t))+q(x。(t))u(x。(t))=tu(x。(t)),x。(t)∈D。(*)其中q是给定的定义在D。上的有界Ho。lder连续函数.本文解决了上述扩散方程(*)的随机Dirichlet问题的解在S3内存在性及唯一性问题.  相似文献   

8.
智慧窗     
cos7。 cosl 27。 cos247。一9湖北大冶师范学校(4 3,5100) 王三宝 易秀英 (答案在本期找)智慧窗《巧求值》参考答案 在z轴上以A,为起点取单位向量i.如图作边长为1 彳的等边三角形A,A2A。,使A1A。与i的夹角为7。.则A2A3与i的夹角为127。,A。A-与i的夹角为113。.于是A。A2 A。A。 A。A,在i上的投影为cos7。 cosl27。 cosll3。一cos7。 cosl27。 cos247。一O(因为AlA2 A2A3 A。Al一0). 口智慧窗…  相似文献   

9.
二项展开式收敛区间端点敛散性判定一种方法刘平(天津理工学院)在许多高等数学的教材中,都有二项展开式的公式。在。。端点。。-W。。。。。。f.K。。,。,。一切。。。[。,’riJ。[--l·1。,。~1.,。,l。。。间为(一1,l」的结论,在许多理...  相似文献   

10.
论数值修约     
数值修约的已有定义是从其现象来定义的。现在提出的定义是从数值修约的本质(用加减法使尾数化零)来定义的。因而按定义可直接推导得到种种结论。并可以此来定义各种数值修约规则。对一个数值连续修约的可行性作了解释。对修约间隔亦有论述。本文提出了五轮换规则的想法。关于两个数值修约规则的中文名称,主要是指出它们用常量(四、五、六)表示变量,因而产生逻辑上的错误。本文也讨论产生错误的原因,并同时指出其他错误。新名称的提出已不犯原有错误。  相似文献   

11.
Least squares solution of linear inequalities appears in many disciplines such as linear separability problems and inconsistency correction. In this paper we consider this problem with uncertainty in its data. Then we prove that its robust counterpart is equivalent to a second order conic linear optimization problem, which can be efficiently solved using interior point methods.  相似文献   

12.
J.‐P. Barriot  M. Benna 《PAMM》2003,2(1):507-508
In this paper, we derive a third order differential equation resulting from the linearization of an eikonal equation arising in a physical problem of radio tomography. We show that this equation as a unique solution and study its numerical solution.  相似文献   

13.
奇摄动非线性微分方程初值问题的双重层解   总被引:5,自引:0,他引:5  
陈秀 《应用数学学报》2001,24(2):291-294
本文研究一类二阶非线性微分方程初值问题的奇摄动,揭示了其解呈现双重层性质,在适当的假设条件下,利用微分不等式理论,得到了解的存在性和具有不同量级校正项的渐近开式。  相似文献   

14.
The purpose of this paper is to develop a useful technique for solving linear programmes involving more than one objective function. Motivation for solving multicriterion linear programmes is given along with the inherent difficulty associated with obtaining a satisfactory solution set. By applying a linear programming approach for the solution of two person–zero sum games with mixed strategies, it is shown that a linear optimization problem with multiple objective functions can be formulated in this fashion in order to obtain a solution set satisfying all the requirements for an efficient solution of the problem. The solution method is then refined to take into account disparities between the magnitude of the values generated by each of the objective functions and solution preferences as determined by a decision-maker. A summary of the technique is then given along with several examples in order to demonstrate its applicability.  相似文献   

15.
In this paper, we study the approximation of reverse parabolic problem with integral boundary condition. The Rothe difference scheme for an approximate solution of reverse problem is discussed. We establish stability and coercive stability estimates for the solution of the Rothe difference scheme. In sequel, we investigate the first order of accuracy difference scheme for approximation of boundary value problem for multidimensional reverse parabolic equation and obtain stability estimates for its solution. Finally, we give numerical results together with an explanation on the realization in one- and two-dimensional test examples.  相似文献   

16.
In this paper, we are interested in the solution of a viscous scalar conservation law. We remark that its first order spatial derivatives solve a system of partial differential equations presenting a nonlocal nonlinearity. We associate a nonlinear martingale problem with this system. After proving existence and uniqueness for the martingale problem, we obtain a propagation of chaos result for a system of interacting diffusion processes. We deduce that it is possible to approximate the solution of the viscous scalar conservation law thanks to the interacting diffusions  相似文献   

17.
The paper deals with the second order differential systems with periodic boundary conditions. In the first part of the paper four different methods are employed to find the unique solution of the linear systems. One of the methods is a shooting type which converts the periodic boundary value problem into its equivalent initial value problem. In the second part of the paper several sufficient conditions are provided for the existence and uniqueness for the nonlinear systems. The technique developed for the linear systems to convert into its equivalent initial value problem is used in an iterative way for the nonlinear systems. It is shown that the iterations converge quadratically.  相似文献   

18.
In this paper, we establish a decomposition theorem for polyharmonic functions and consider its applications to some Dirichlet problems in the unit disc. By the decomposition, we get the unique solution of the Dirichlet problem for polyharmonic functions (PHD problem) and give a unified expression for a class of kernel functions associated with the solution in the case of the unit disc introduced by Begehr, Du and Wang. In addition, we also discuss some quasi-Dirichlet problems for homogeneous mixed-partial differential equations of higher order. It is worthy to note that the decomposition theorem in the present paper is a natural extension of the Goursat decomposition theorem for biharmonic functions.  相似文献   

19.
In this paper we propose a class of differentiable gap functions in order to formulate a generalized variational inequality (GVI) problem, involving a set-valued map with closed and convex graph, as an optimization problem. We also show that under appropriate assumptions on the set-valued map, any stationary point of the equivalent optimization problem is a global optimal solution and solves the GVI. Finally, we describe descent methods for solving the optimization problem equivalent to the GVI and we prove its global convergence.  相似文献   

20.
In this paper we study mathematically an industrial problemrelated to sterilization processes involving heat transfer bynatural convection. We give results of existence and regularityfor the solution of this problem. We recast the whole problemas an optimal control problem with pointwise constraints onthe state and the control in order to ensure the reduction ofmicroorganism concentration and the retention of nutrients,and to save energy. Finally, we give results on existence ofthe optimal solution and optimality conditions for its characterization.  相似文献   

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