采样分布

Consider the dependencies between the coefficients and their parents, a non-Gaussian bivariate distribution is given, and corresponding nonlinear threshold function is derived from the model using Bayesian estimation theory. According to non-subsampled Contourlet transform and bivariate threshold function, a novel Non-Subsampled Contourlet Transform based on Bivariate threshold function for image denoising is proposed. This scheme achieves enhanced estimation results for images that are corrupted with additive Gaussian noise over a wide range of noise variance.

该文依据非下采样Contourlet分解系数与其父系数之间的相关性，给出非高斯双变量分布，对该模型应用Bayes估值理论推导得到相应的非线性双变量阈值函数，综合非下采样Contourlet分解和双变量阈值函数，提出一种基于双变量阈值的非下采样Contourlet变换图像去噪方法。

Based on the data of hydrography, measured waves, sediments, drilling Quanternary strata, microorganism, sporopllenin, landforms, climate and others in Zhoushan Islands channels, the strait channel effects are systematically studied.

本文根据舟山群岛峡道内分布于虾峙门、马岙、金塘水道和册子水道的水文泥沙实测资料，北仑港、野鸭山和虾峙门口门区的波浪观测资料，北仑电厂运煤码头前沿的第四纪地层钻孔资料、微体古生物鉴定和孢粉分析资料和虾峙门口门区5米浅钻资料，分布于金塘水道、册子水道、马岙三江口海域、虾峙门口门区和杭州湾南部的海底沉积物采样分析资料，册子水道东部野鸭山潮滩和马岙三江口潮滩的沉积物采样分析资料、潮滩地貌的踏勘资料、舟山群岛峡道地区的海图资料以及舟山群岛地区气象气候等其它资料，对舟山群岛峡道效应进行了综合性的系统研究。

In this paper,we propose a novel model named distribution-free data density estimation,which is based on distribution-free(i.e.,independent of data distributions) sampling on global cumulative distribution to achieve high estimation accuracy with low estimation cost regardless of distribution models of the underlying data.

分布无关密度估计算法首先将底层数据的任意分布转换成一中间分布——累计概率分布函数。由于累计概率分布函数的输出在[0，1]之间均匀分布，因此接着对累计概率分布函数的输出随机采样，可以准确估计当前网络中数据的密度分布。

When oversampling factor is 2, the covariance matrix composed of the coefficients of correlation between those samples can be calculated by numerical method.

按Nyquist采样率均匀抽取出的采样点之间相互独立同分布，推广到过采样系数为2时，得到此时由各采样点之间相关系数构成的协方差矩阵，利用数值计算对其进行分析。

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。

The experiment show that the sampling strategy using Halton points is better than the random sampling strategy at sampling points distribution.

实验结果表明，Halton点采样策略比一般的随机采样策略具有更好的采样点分布。

Systematic grid sampling is the most popular method at present, but it could loss some important distribution information. Systematic unaligned sampling is the most ideal method. It is easy to find periodical distributing field information with systematic unaligned sampling method.

其中规则栅格采样是目前最常采用的方法，但容易丢失一些比较重要的分布信息；系统分层采样是最理想的方法，容易发现具有周期性分布的农田信息。

Based on the strong relationship about frames near by, the Author brought forward an particle filter algorithm importing weighted sampling about pre-frame in object tracking. The algorithm resolves the trickiness in traditional SIR algorithm which depends on statcmodcl acutely by importing proposal distribution. The algorithm can track object which movement is irregular.

根据相部帧间信息的强关联性，提出一种引入前帧加权采样的粒子滤波目标跟踪算法，解决了传统采样重要性重采样(SIR算法由于引进提议分布而需要严重依赖目标的系统状态模型的问题，可以理想跟踪运动状态不规则的目标。

Then, we present an efficient sampling algorithm on the unit sphere, and the generated point distribution can match the SRBF representation. We are capable of creating images with multiple measured BRDFs under global illumination.

此外，根据球面射基底函的表现形式，我们也提出一种有效的重要性采样方法，其产生出的采样分布可以合球面射基底函所描述的资分布，此方法可以在全域光源照射的环境下，有效地绘制包含多种复杂材质的场景影像。

Through field observations and sampling, by referencing to other documents and information, with correlation analysis and principal component analysis as mathematical tools, we know that: the distribution of the number of birds has close relations with density of zoobenthos and ratio of water area, the correlation coefficient of the distribution and the two factors are 0.916 and 0.745, the density of zoobenthos is the most direct reflection; Vegetation types , the coverage and water level may have relations with the distribution of the kind of birds, normally, middle and large volume birds need high vegetation and high coverage as their habitats, and waterfowl like deep water as their habitats; Human activities have low impact on the the distribution of the number of birds, but the activities have relations with all the other environmental factors.

通过实地的观测、采样，并结合其他文献的资料，以相关分析和主成分分析作为数学工具，得知：鸟类的数量分布和底栖生物密度、水域面积比例有着密切关系，鸟类数量分布与两者的相关系数分别为0.916和0.745，其中，底栖生物密度是鸟类数量分布的最直接反映；植被类型、植被盖度和水位可能与鸟类的种类分布有一定关系，通常体积中、大型的鸟类需要较高的植被高度，来作为自己的栖息场所，水禽需要水位较深的区域作为自己的栖息场所；人为活动对鸟类数量分布的影响不大，但对所有自然环境因子都有一定影响。

And Pharaoh spoke to Joseph, saying, Your father and your brothers have come to you.

47：5 法老对约瑟说，你父亲和你弟兄们到你这里来了。

Additionally, the approximate flattening of surface strip using lines linking midpoints on perpendicular lines between geodesic curves and the unconditional extreme value method are discussed.

提出了用测地线方程、曲面上两点间短程线来计算膜结构曲面测地线的方法，同时，采用测地线间垂线的中点连线和用无约束极值法进行空间条状曲面近似展开的分析。