查询词典 probability density function

Simulation experiments' data show that by using this methods it can precisely generate non Gaussian correlate random sequence with specified probability density and power spectrum,and reproduce verisimilarly the scatter coherent video signal of radar sea clutter containing both amplitude and phase.

其中迭代算法用来计算非线性变换过程中高斯序列相关性的变化，而随机向量法用来完成线性变换，仿真实验数据证明利用这种方法可精确地产生具有指定概率密度和功率谱的非高斯随机序列，逼真地复现既包含振幅又包含相位的雷达海杂波相干视频散射信号。

The control criteria of system stochastic optimal control involving the probability density evolution analysis are presented in reference to the physical senses of control objectives, and three classes of control criteria hinging on evolution processes with hierarchical levels are developed.

从目标控制量的物理意义出发，提出了基于系统概率密度演化分析的最优控制准则，建立了递阶层次的演化过程控制准则类。

But these abnormal information may result in higher Gaussian probability density. This paper presented the UKFVSMMPDA algorithm for ground maneuvering target track in cluttered environment.

但这些非正态信息却可能导致较高的非高斯概率密度，文中将机动和多回波同时考虑，并充分利用了地形特征等信息，提出了UKFVSMMPDA算法，对密集回波环境下地面机动目标进行跟踪。

In addition, the ingredients have been tested by the IR spectra which show the probability of the nano-porous structure. SEM pictures, specific surface areas and distribution of pore diameter have been tested to study the nano-porous structures in surface and some data before and after the pyrolyzing process have been gained: the size of the organic aerogel is 30~50nm, that of the carbon aerogel is about 10nm, the specific surface area increases from 341.77m^2/g to 452.75m^2/g, the density increases from 0.1708g/cm^3 to 0.3356g/cm^3 respectively.

借助有机气凝胶的红外光谱研究了其化学结构，说明其网孔结构形成的可能性；研究了有机气凝胶的扫描电镜图像、比表面积及孔径分布等，并得到碳化前后的一些对比数据：有机气凝胶颗粒大小30~50nm，碳化后约为10nm，比表面积从341.77平方公尺/g增大到452.75平方公尺/g，密度从0.1708g/立方公分增大到0.3356g/立方公分。

In this paper a full density matrix treatment is adopted to deal with the interaction between long-pulse, circularly-polarized light and the sodium atoms. The time evolution curve of each of the 24 sub-state's population probability can be obtained by solving the Bloch equation of twenty-four hyperfine levels.

采用密度矩阵方法来处理长脉冲光与钠原子的相互作用，求解24能级钠精细结构的布洛赫方程，给出参与跃迁的每个态密度随时间的演化曲线。

Features: high efficiency, small amplitude and high frequency of screening; it differs from the conventional screens with breaking of the surface tension of pulp and small granularity high speed vibration on sieve cover and accelerates the separating of large-density useful mines and increase the contacting probability of the materials smaller than output granularity and the sieve pore.

高频筛效率高、振幅小、筛分频率高。与普通筛分设备的原理不同，由于高频筛采用了高频率，一方面破坏了矿浆表面的张力和细粒物料在筛面上的高速振荡，加速了大密度有用矿物和析离作用，增加了小于分离粒度物料与筛孔接触的概率。

An equal cross-section blade was investigated and a finite element model was built parametrically. Geometrical parameters (such as length, width and thickness), material parameters (such as young's modulus and density) and speed of blade were considered as input random variables while the static frequencies and dynamic frequencies were output random variables. Combining the finite element method, response surface method and Monte Carlo method, the statistical properties and cumulative distribution functions of static frequencies and dynamic frequencies were obtained. Probability sensitivities analysis, which combined the slope of the gradient and the width of the scatter range of the random input variables, was applied to quantitatively evaluate the sensitivities of static frequencies and dynamic frequencies with respect to the random variables. The Scatter plots of structural responses with respect to the random input variables were illustrated how to adjust the values of the static frequencies and dynamic frequencies by changing input random variables.

文中以某试验台用汽轮机等直叶片为研究对象，考虑几何参数、材料参数和转速的随机性，通过有限元参数化建模，将确定性有限元方法、响应面方法和Monte-Carlo模拟法相结合，从而获得了叶片静频、动频的统计特性和累积分布函数；同时考虑随机变量的梯度和离散范围对静、动频的影响，通过概率敏感性分析，定量地判断出叶片静、动频对随机输入变量的敏感性；通过绘制叶片静、动频与输入变量的散点图，定量地分析了如何改变随机变量以调整静、动频率的方法。

The theoretical and experimental probability density distribution for the particle velocity follows normal law and is hardly affected by the particle characteristics.

颗粒的理论与实测的速度概率密度与颗粒物性关系不大且都遵循正态分布。

Separation criteria based on minimum mutual information of time-domain blind deconvolution was obtained on the basis of probability density estimation.

在概率密度估计的基础上，得到时域盲解卷积的基于最小互信息的分离准则。

Therefore, the EL spectra of (Znq_2)_4 is wider than that of Znq_2. 4._2 was synthesized. The analysis of molecular spatial structure and the characterization of material performance of_2 and Liq showed that two Liq molecules and two Naq molecules were connected by Na-O-Na bond bridges to form_2. Compared with Liq,_2 exhibits stronger rigidity in planar molecular structure, larger steric hindrance and intermolecular distance, and much smaller molecular polarity, thus resulting in much longer fluorescence lifetime, much higher fluorescence quantum efficiency, wider energy bandgap and better film formability. When used as light-emitting layer in OLED,_2 shows lower formation probability of excited dimmer and exciplex formation than Liq, thus emits bluer light with higher current efficiency than Liq. When_2 ultrathin film is used as electron injection layer in OLED, it exhibits higher current density, higher luminance, lower turn-on voltage and higher current efficiency than Liq ultrathin film for the existence of sodium ions in_2 ultrathin film. 5. The summarization the relationship between molecular spatial structure and material performance of Alq_3,(Znq_2) and Liq, lead the conclusion that the molecular spatial structure of Mq_n affects its material performance in such aspects as the rigidity of planar molecular structure, intermolecular interaction, molecule stacking mode and intermolecular distance.

制备了_2，通过对_2和Liq的分子空间结构与性能进行分析与讨论，发现_2是通过两个Na-O-Na键桥将两个Liq和两个Naq连接构成的，其分子平面结构的刚性程度强于Liq，空间位阻大于Liq，分子之间的距离大于Liq，分子极性远远小于Liq；_2的荧光寿命长于Liq，荧光量子效率高于Liq，成膜性优于Liq；_2的禁带宽度比Liq大，光致发光光谱中_2的最大发射峰较Liq发生蓝移；当_2在OLED中作为发光层时，激发二聚体与激基复合物的生成几率远远小于Liq，发的光比Liq更蓝，电流效率大于Liq；_2超薄膜中有Na离子的存在，与Liq超薄膜相比，当其在OLED中作为电子注入层时，具有更大的电流密度，更高的发光强度，更低的阈值电压和更高的电流效率 5、对上述Alq_3、Znq_2和Liq的分子空间结构与材料性能之间的关系进行了归纳总结，认为Mq_n的分子空间结构主要在分子平面结构的刚性程度，相邻分子之间的相互作用，分子堆叠的方式和分子之间的距离这四个方面影响其性能。

Many will continue to choose to live in duality and in conflict.

许多人将继续选择活在二元对立性和冲突中。

I find that students of the University of Physical Education all wear sportswear at first sight.

我发现：体育大学的学生乍一看，都是穿运动衣，大家都一样