阶矩
- 与 阶矩 相关的网络例句 [注:此内容来源于网络,仅供参考]
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Experiment results show that binary tree SPIHT suits to true bidimensional wavelet decomposition and it is testified that in true bidimensional wavelet decomposition, the compression effect is comparable between image decomposed by wavelet FB with low order VMs but good interpolating characteristic and that with higher order VMs.
实验证实了二叉树的编码更适合纯二维小波分解,同时也证实了在纯二维小波分解中内插性能好的低阶消失矩的小波滤波器能够产生与高阶消失矩的小波滤波器相同或更好的压缩效果。
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The modified double weight function method is to introduce new weight functions doing subtraction between two negative exponential-type functions. For a Pearson type three probability distribution, the MDWF is able to make estimations of the Standard Deviation and Coefficient of Skewness C(subscript S from the second-order weighted central moments reduced to the first-order weighted central moment estimations.
修改的双权函数法是将两个负指数型函数之差所构成的函数类取作权函数,对于皮尔逊Ⅲ型分布,它能使σ和Cs的估计由原权函数法的二阶加权中心矩降低为一阶加权中心矩估计。
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Spatial white noise is considered first then the spatial colored noise. Two method based on 1st and 2nd order cyclic moments, CERA, and then 3rd order cyclic moment, MCERA, are proposed separately.
分白噪声及有色噪声两种情况,分别提出了基于一、二阶循环矩的CERA方法和基于三阶循环矩的MCERA方法。
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ABSTRACT Aiming at problems of trans-vector controller in a vehicle-carried induction motor such as variable rotor and stator resistance following motor temperature, and their inductance varying with flux saturation degrees. Firstly, CSI and VSI are introduced, for CSI, it can hold the advantages both FOC and DTC using stator flux directional, PI parameter and simulation are also introduced. Secondly, equations of IM in the synchronous rotary frame and its static counterpart, as figuring in the saturation condition of magnetic field, are dealt in this paper and the simulation results are presented. Thereafter, the parameter designing of PI trans-vector controller is processed, which features the non-linear model. In practical realization, as neglecting the dynamical change of motor inductance, this paper employs online modification of inductance parameters, according to the flux saturation, then transforms the non-linear equations into linear ones, and so compacts the structure of controller. Thirdly, in view of the maximum torque output is extraordinary requisite when Electrical Vehicle start up, accelerate, and overtake, this paper issues the maximum torque when both inverter and battery capacity is corporeally definite. Fourthly, on-line differentiating and analyzing both rotor's time constants and its flux by using the expanding order reduction and discrete Kalman filter equation are fathomed, in order to realize high-performance trans-vector algorithm, and also the simulation results are presented. Fifthly, the close-loop regenerative brake system, when the EV's torque is set constant, is deduced; at the same time, unification of electric drive model and brake model is executed. Combined with maximum charge current demands, the mathematical model for online yielding torque as a demand.
本论文针对车载异步电机在矢量控制器所遇到的问题:定转子电阻随温度变化及随电机饱和程度变化的转子电感及定子电感而影响电机调速性能提出一套完整的解决方案:分析了电流型逆变器和电压型逆变器在实现矢量控制时控制器参数的计算,分析出对于电流型逆变器在采用定子磁场定向时,其性能同时具有矢量控制和直接转矩控制两者的优势,并对电压型逆变器在转子磁场定向下的模型进行了仿真研究;建立异步电机非线性模型,推导出考虑磁饱和时异步电机在同步旋转坐标系及静止坐标系下的方程,并做出了仿真结果,建立异步电机在非线性模型下的矢量控制调节器的PI参数设计,在实际应用中,若忽略电机电感的动态变化,可以根据当前的磁路饱和状态而在线修正电感参数,从而将非线性方程线性化,降低控制器的复杂度;考虑到电动汽车在起动和加速超车时需要电机有最大转矩输出,本文讨论在逆变器容量一定和电池供电能力有限的情况下电机最大转矩输出问题;推导了异步电机扩展降阶、离散卡尔曼滤波方程在线辨识转子时间常数和转子磁通,用于实现高性能的矢量控制算法,并给出了仿真结果;推导出了电动汽车恒转矩给定的闭环回馈制动系统,实现了电动控制模型和制动模型的统一,而且结合铅酸电池最大充电电流的要求,为制动转矩在线给定建立了数学模型;设计了基于双DSP系统的高性能矢量控制器软硬件框图,并以大量实验数据说明矢量控制在电动汽车应用的实际应用状况。
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For this objection, we propose a kind of optimal interpolator in the senes of the minimizing mean square error, which using the image nonseparable autocorrelation function model and characteristic of circular quincunx interpolator's coefficient distribution. The experiments testified that the interpolating characteristic of APIDCSF is similar to the optimal interpolator. A quasi-vanishing moment curve is proposed here.
消失矩高的滤波器内插性能好于消失矩低的滤波器,或者说支撑大的滤波器内插性能好于支撑小的滤波器,对于支撑相同但消失矩不同的不同类滤波器,提出了准消失矩曲线,可以检测二维不可分离的内插滤波器的内插性能以及在相同支撑下低阶消失矩与高阶消失矩滤波器的相似度。
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Considering nodal pressure as the evaluating indicator, functional reliability indexes of the nodes were calculated by the mean-first-order-second-moment method which was originally developed for structural reliability analysis.
在进行供水管网的抗震功能可靠度分析时,借鉴结构可靠度的分析方法,以节点水压为评价指标,采用均值一次二阶矩方法计算管网各节点的功能可靠度,该方法通过一次水力分析即可给出震后低压供水和渗漏状态下管网各节点的可靠性指标,较之前发展的随机模拟方法大为简化且概念清晰。
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Considering nodal pressure as the evaluating indicator, functional reliability indexes of the nodes were calculated by the mean-first-order-second-moment method which was originally developed for structural reliability analysis.
在进行供水管网的抗震功能可靠度分析时,借鉴结构可靠度的分析方法,以节点水压为评价指标,采用均值一活动板房次二阶矩方法计算管网各节点的功能可靠度,该方法通过一次水力分析即可给出震后低压供水和渗漏状态下管网各节点的可靠性指标,较之前发展的随机模拟方法大为简化且概念清晰。
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Adopting the AFOSM method of reliability analysis, assuming the unit weight, co hesion and internal friction are mutually independent stochastic variables, thei r influence on the reliability of the tension resistance of the anchor rod has b een analyzed.
采用可靠度分析的改进一次二阶矩法,假定粘性土的重度、粘聚力、内摩擦角为互相独立的随机变量,分析了它们对于锚杆抗拉力可靠性的影响。
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A two-fluid model together with a k-ε-kp two-phase turbulence model is used to predict swirling gas-particle flows in coaxial jets discharged into a sudden expansion chamber.
由统一二阶矩的两相湍流模型出发,在各向同性的条件下获得k-ε-kp两相湍流模型。
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By different combinations of MIR, ASM, SSW, and MSA, the images can be classified into four classes.
由近远场灰度比、奇异标度差、多重谱面积和基于小波变化的角二阶矩四个特征量组合进行图像识别。
- 推荐网络例句
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This one mode pays close attention to network credence foundation of the businessman very much.
这一模式非常关注商人的网络信用基础。
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Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.
扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。
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There is no differences of cell proliferation vitality between labeled and unlabeled NSCs.
双标记神经干细胞的增殖、分化活力与未标记神经干细胞相比无改变。