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1.
从基本定理楞次定律出发,对运动载体涡流磁场的磁变模拟方法进行了严格的论证并推导得到不同情况下的磁变模拟公式。针对形式复杂的磁变模拟函数在涡流磁场数值计算和测量等研究可能带来的问题,提出采用级数分解的方法对一般磁变模拟函数进行处理。两个磁变模拟函数级数分解结果表明:合理地选择级数分解的截断项数时,级数分解结果可较好地逼近磁变模拟函数,为磁变模拟方法应用载体涡流磁场的相关研究拓宽了思路。  相似文献   

2.
变权评估中均衡函数的构造   总被引:1,自引:0,他引:1  
针对变权评估问题,介绍了基本原理,研究了均衡函数的构造方法,提出了激励型和惩罚型均衡函数的概念.考察了两类基本的均衡函数:和型均衡函数与积型均衡函数,通过其函数项与导数的讨论,研究了函数的构造条件以及其最终成为激励型和惩罚型均衡函数的条件,并结合具体例子进行了分析.所得结论具有普遍的意义,丰富了变权评估的理论体系.  相似文献   

3.
本文推证了一个积分展开定理。根据这个定理,一个闭区间上定义的具有展成泰勒级数条件的函数,可以在一个特定的基函数上展开,而其展式的系数总含有这个函数在该区间上的多重积分。然后给出一个将该定理应用于制导的例子。  相似文献   

4.
根据简化拉普拉斯函数级数展开和将级数展开为连分式的方法,将简化拉普拉斯函数化为连分式形式。推导出基于连分式的简化拉普拉斯函数渐近分数的递推计算公式,讨论了递推计算中误差控制的方法。计算结果表明,该算法简单实用,在炮兵及防空兵火力毁伤概率计算中有应用价值。  相似文献   

5.
将边界上的函数展成小波级数,利用循环矩阵方法,从核函数边界上的值,得到离散的积分方程系数矩阵,求解未知的小波级数系数,从而得到边界积分方程近似解,文中计算了一个二维拉普拉斯方程的解。  相似文献   

6.
给出了误差函数与炮兵简化拉普拉斯函数的关系,分析了误差函数各种计算方法如级数展开法、不完全伽马函数法和近似计算公式的优缺点,讨论了用误差函数计算公式进行炮兵简化拉普拉斯函数计算的方法,最后通过误差函数导出了炮兵拉普拉斯函数一个新的近似公式。  相似文献   

7.
利用累积失效函数给出失效率递增(减)类,平均失效率递增(减)类,新比旧好(差)类,按失效率新比旧好(差)类和按平均失效率新比旧好(差)类的等价刻画。通过与指数分布的对比,给出了描述这些分布类的等价条件。利用特定函数类的复合封闭性,给出以上分布类在加速寿命系统和协同系统中的封闭条件的统一证明。  相似文献   

8.
首先,分析了矩阵式中频电源的空间矢量调制策略,借鉴正弦脉宽调制技术推导出等效开关函数的解析表达式;然后结合三周期变量函数傅里叶级数展开式的推导,求得了等效开关函数的频域特性;最后,基于频域卷积定理,推导了输出电压的频谱函数,归纳了矩阵式中频电源输出电压的谐波特性。解析结果与采用快速傅里叶变换方法得到的结果吻合良好,验证了文中理论方法的正确性。  相似文献   

9.
本文给出了圆锥体上沿任意方向放置小天线时场强的级数表示式,推导出了在圆锥体上不同位置不同方向放置小天线时辐射电阻的计算公式。着重讨论了双重级数求和问题使之适于数字计算。对于圆锥体和同半径圆柱体上同样小天线辐射电阻的等效问题,从一定条件下的具体计算和试验比较中得出了一些结论表明两者可以等效。本文最后附有小锥角时勒让特陪函数(Associated Legendre function)及其对θ微商的前几个根以供查考。  相似文献   

10.
本文在介绍任意函数电路机助设计方法的基础上,用切比雪夫多项式级数模拟热电偶温度—电压特性,并设计出相应的函数电路。所述的方法实际上适用于模拟任意函数。  相似文献   

11.
In this paper we consider the problem of maximizing the sum of certain quasi-concave functions over a convex set. The functions considered belong to the classes of functions which are known as nonlinear fractional and binonlinear functions. Each individual function is quasi-concave but the sum is not. We show that this nonconvex programming problem can be solved using Generalized Benders Decomposition as developed by Geoffrion.  相似文献   

12.
将小波包变换理论应用于多载波码分多址(MC-CDMA)系统,提出一种基于小波包函数的正交调制方法.系统中,发端数据串并转换成若干子信道,每个子信道的数据进行直序扩频,不同子信道上的数据以chip调制不同的小波包函数作为基带传输波形.小波包函数的一系列优良性质,使系统能有效地抗多径干扰,抑制子信道串扰、多址干扰等.本文对系统在多径Rayleigh慢衰落信道中的性能,进行了理论分析和计算机仿真.结果表明,本系统比基于DFT的MC-CDMA有较大的性能改善.  相似文献   

13.
地方高校制定发展规划是适应国内外高等教育发展的客观需求,是区域经济社会发展的必要需求,是高校自身发展的迫切需求。地方高校要履行高校职能,更好地为地方经济社会发展服务就必须科学制定规划,特别是要战略规划学校的办学定位、特色和目标。同时,规划的实施要强调监控并要与高校职能协调统一。  相似文献   

14.
Sei-Hoon Moon 《防务技术》2021,17(2):617-632
This paper provides a review of methods of assessing a fragmentation weapon's effectiveness against a point target or an area target with keeping the focus on the necessity of using the Carleton damage function with the correct shape factor.First,cookie-cutter damage functions are redefined to preserve the shape factor of and to have the same lethal area as the corresponding Carleton damage function.Then,closed-form solutions of the effectiveness methods are obtained by using those cookie-cutter damage functions and the Carleton damage function.Finally,the closed-form solutions are applied to calculate the probability of damaging a point target and the expected fractional damage to an area target for several attack scenarios by using cookie-cutter damage functions and the Carleton damage functions with different shape factors.The comparison of the calculation results shows that using cookie-cutter damage functions or the Carleton damage function with a wrong shape factor results in quite signifi-cant differences from using the original Carleton damage function with a correct shape factor when weapon's delivery error deviations are less than or comparable to the lengths of the lethal area and the aim point is far from a target.The effectiveness methods improved in this paper will be useful for mission planning utilizing the precision-guided munitions in circumstances where the collateral damage should be reduced.  相似文献   

15.
We derive formulas for the variance of that proportion of the value of a randomly located, circularly symmetric area target that is destroyed by N independently fired weapons of identical type whose damage functions are circularly symmetric about the respective impact points. The probability density functions of the target center location and of the weapon impact points are also circularly symmetric. The general results are specialized to uniform and Gaussian functions. In the latter case a closed-form solution (triple integral) for the variance of the coverage is derived. Similar to some well-known results on expected coverage, this expression for the variance of the coverage can be easily evaluated by numerical quadrature. Numerical results are given which indicate the target coverage variability caused by the combined effects of random target-locating errors and weapon impact point fluctuations.  相似文献   

16.
This paper develops a mathematical theory for predicting force annihilation from initial conditions without explicitly computing force-level trajectories for deterministic Lanchester-type “square-law” áttrition equations for combat between two homogeneous forces with temporal variations in fire effectivenesses (as expressed by the Lanchester attrition-rate coefficients). It introduces a canonical auxiliary parity-condition problem for the determination of a single parity-condition parameter (“the enemy force equivalent of a friendly force of unit strength”) and new exponential-like general Lanchester functions. Prediction of force annihilation within a fixed finite time would involve the use of tabulations of the quotient of two Lanchester functions. These force-annihilation results provide further information on the mathematical properties of hyperbolic-like general Lanchester functions: in particular, the parity-condition parameter is related to the range of the quotient of two such hyperbolic-like general Lanchester functions. Different parity-condition parameter results and different new exponential-like general Lanchester functions arise from different mathematical forms for the attrition-rate coefficients. This theory is applied to general power attrition-rate coefficients: exact force-annihilation results are obtained when the so-called offset parameter is equal to zero; while upper and lower bounds for the parity-condition parameter are obtained when the offset parameter is positive.  相似文献   

17.
Infinite-horizon, countable-state, continuous-time Markovian decision models are solved by formulating as a pair of infinite linear-programming problems. Expected discounted and average returns are considered as criterion functions. For both criterion functions, the existence of deterministic optimal stationary policies is established by solving the associated infinite linear-programming problems. Computational procedures for finite state and action sets are discussed by considering associated finite linear-programming problems.  相似文献   

18.
代数免疫度最优的旋转对称布尔函数的构造   总被引:2,自引:1,他引:1       下载免费PDF全文
代数免疫度是布尔函数的一个重要密码学指标,为了抵挡代数攻击,密码算法中所使用的布尔函数应当具有较高的代数免疫度.本文利用“轨道交换”技术,给出了一类具有最优代数免疫度的旋转对称布尔函数的构造,该类函数对于代数攻击具有较强的抵抗能力,同时具有较高的非线性度和最优代数次数.  相似文献   

19.
磁偶极子信号检测和参数估计   总被引:1,自引:0,他引:1  
在分析了经典磁偶极子模型的基础上 ,指出该模型是两个函数的组合 ,目标参数包含在这两个函数的参数里 .提出了二次函数组合法 ,能够在绝大多数情况下将这两个函数分离 ,逐步求出目标参数 .最后对实例进行了仿真计算 ,给出了较满意的结果  相似文献   

20.
为了实现对OPNET软件强大功能的跨平台调用,提出了一种基于Web服务的OPNET功能封装模型.该模型以数据库为中介实现了OPNET程序与外部系统的交互,通过批处理文件调用了OPNET程序,进而将OPNET程序封装为OPNET Service的服务并发布到服务注册中心,外部应用程序可以通过查找注册中心查找实现对OPNE...  相似文献   

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