随机

If the value of two-dimension random variable is finite or countable, then is called two-dimension discrete random variable.

Definition 3.3 如果二维随机变量可能取的值只有有限个或可列个，则称为二维离散型随机变量。

The discrete random height variable of worn surface is described with continuous random variables by a mathematical method.

建立了磨损表面轮廓数值化基准、用连续随机变量来描述磨损表面轮廓线高度离散随机变量，对磨损表面高度分布作了数理统计分析，研究了载荷、滑动速度及镀层种类对磨损表面几何特性的影响，将数理统计分析结果与镀层的耐磨性作了比较分析，较为完整、深入地描述了磨损表面的几何特性。

The principles of suppressing random noises with K-L transformation in wavelet conversion domain are that 1 wavelet decomposition is carried out on seismic signals to form wavelet packet sections in time sharing and frequency division, 2 K-L transformation is utilized to remove noises on sections, and 3 the de-noise wavelet packet sections are reconstituted into seismic sections to remove random noises.

介绍了小波变换域K-L变换压制随机噪声的基本原理，即先将地震信号进行小波分解形成分时分频的小波包剖面，然后用K-L，变换对小波包剖面进行去噪，再将去噪后的小波包剖面重构回地震剖面，从而达到消除随机噪声的目的。

Methodssixty four patients were randomly divided into two groups, a and b, with 32 patients in each group. dobell solution was given to those in group a for gargle, six times a day; for those in group b, 50 g/l sodium bicarbonate and dobell were applied for gargle alternatively, six times a day. the infection was observed one and two weeks later.

随机抽取大剂量化疗后成年白血病住院病人64例，随机分成a、b两组，各32例。a组给予多贝尔液漱口，b组给予多贝尔液及50 g/l碳酸氢钠液交替漱口，每天6次。1、2周后观察两组口腔真菌感染发生情况。

However, in some situations, models are hard to satisfy these assumptions at the same time. We meet a number of random errors with serial correlation and heteroscedasticity in practical problems. The rationality of these assumptions for random errors is doubtable. Therefore, it is necessary to test for correlation and heteroscedasticity in regression, which is an important step of dealing with regression problems and plays an important role in theory and practice.

但实际问题中，回归模型很难同时满足Gauss-Markov的三个假设，人们在实际问题中发现许多随机误差出现序列相关和方差不同的现象，因此对回归模型的随机误差的独立性和方差齐性的假设产生了质疑，从而展开了回归模型的相关性和异方差检验的研究，它是处理回归问题的重要步骤，在理论和应用上都有十分重要的意义。

By using generalized Duhamel's integral and integral transform, this paper investigates random response of an infinite beam on the Kelvin viscoelastic foundation subjected to a moving load.

利用广义Duhamel积分和积分变换，研究了粘弹性Kelvin地基上无限长梁在运动的线源平稳随机荷载作用下的随机响应。

A final has an accuracy of 5cm for the precise ephemeris and 0.1~0.2ns for the clock information.

本文研究了利用随机游走过程模拟对流层延迟残差随机变化的方法。

The "stemma equimultiple random select cross method" and "random mating method" were used to propagate offspring population of Langshan chicken. For each population, the pedigree of individuals were ascended up to 5 generations. Then, their generation increment of inbreeding coefficient was caculated using the regression slope rate.

以狼山鸡为素材，利用"家系等量随机选配法"和"随机交配法"2种保种方法进行继代繁殖鸡群，每个保种群每个世代的鸡只均逐只编制往上追溯5代的系谱图，利用回归斜率分析方法计算世代增量。

Stochastic control system ; limited control ; exact controllability ; backward stochastic differential equation

本文组织如下，第二节引入主要定义，介绍倒向随机微分方程及彭有关随机精确能控性

Neumann series expansion in Monte-Carlo finite element is used to find the stress of fiber winded composite structures with stochastic factor; Structure reliability formula are then given by Monte-Carlo comparison method and Tsai-Hill failure criteria.

将纽曼级数展开的蒙特卡罗随机有限元应用于具有随机因素的纤维缠绕结构的应力求解；然后利用蒙特卡罗直接比较法和蔡希尔失效判据给出该结构的可靠性算式。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。