查询词典 mathematical expectation

Drawing and mathematical instruments stencils, protractors, compasses etc.

trade 绘图和数学仪器(模板，量角器，指南针等)贸易

This represents a fundamental mathematical limit on the best possible lossless data compression of any communication: considering a certain message as a series of realisations of a certain random variable (where the random variable can be "the next letter", or "the next word", or any other subdivision of text), the shortest number of bits necessary to transmit one message is the Shannon entropy of the corresponding random variable, multiplied by the number of realisations in the original text.

当然如果各个队夺冠的几率不等的话，那么熵则不会是5。因为如果从强队开始问问题，则不需要5个问题一般就可以得到答案。而根据哈夫曼编码的启发，我们表示这32个队，不需要平均长度为5的二进制位。从另外一个角度来看，熵作为信息量的大小也是表达能力的衡量，或者是不确定度的衡量和混乱程度的表现。为什么选择log来表示熵呢？如果X的表达能力为H，Y的表达能力为H，那么X+Y的表达能力应该是二者的乘积，所以H = H + H。

The mathematical studies, for example,"from elementary arithmetic to higher mathematics," Herbart asserted,"are to be linked to the pupil's knowledge of nature, and so to his experience...."

举例来说，对于数学的学习，赫尔巴特认为，&从低级的算术到较高级的数学，是和学生的自然知识和他们的经验联系在一起的。&

E. textures that are created by a mathematical formula, images, or environment maps to create the impression of reflections and refractions.

这可能是程序纹理即通过数学公式创建的纹理，图片或者环境映射来制造对反射和折射的效果。

The distribution regularities of flow field of elbow pipe is discussed on the basis of mathematical model.

从基本的数学模型出发，描述了弯管流场的分布规律。

Especially tests of technical and mathematical knowledge have somewhat lower reliabilities in China.

两年以后，在被试结束飞行训练时，收集了所有飞行学员的标准化反馈数据。

This paper introduces DDA, the basic mathematical principles, and presents applications in the analysis of rockfalls and slope stability problems.

在本篇文章将介绍DDA的发展渊源、基本的数理背景以及在比较特殊的落石与边坡稳定问题分析上的应用。

But while sabbaticals at the Hoover Institution and job opportunities on Wall Street are nothing to sneeze at, the central cause of the profession's failure was the desire for an all-encompassing, intellectually elegant approach that also gave economists a chance to show off their mathematical prowess.

但是，尽管在胡佛研究所作休假年的研究，或是在华尔街找到就业的机会都是不容小觑的良机，这个行当失败的中心原因乃是那种苦苦追求一条无所不包的、思维上优雅的、并能给经济学家机会以炫耀数学才能的研究路径。

Combing with the fundamental thought of the particle system,jet length and atomizing angle are described as macroscopic properties of oil atomization.Based on analyzing the oil atomization process and the created mathematical model,using Visual C++ and OpenGL library with object-oriented method,the shape of oil atomization under variable voltage is simulated.

结合粒子系统的基本思想，以射流长度和雾化角作为宏观特性描述了油液的雾化情况，使用Visual C++结合面向对象技术和OpenGL图形库，根据所建立的数学模型，模拟了不同电压下油液的静电雾化形态。

Freeze-drying is a very complicated non-linear process of heat and mass transfer. It is difficult to establish a precise mathematical model.

冻干过程是一个非常复杂的非线性的传热传质过程，难以建立精确的数学模型。

A carrier gas such as nitrogen is directed through line 20 and valve 22 to connect with line 26 and mix with the gas sample.

如氮气之类的载体通过管线20和阀22引入，与管线26相通，与气体样品混合。

But for the most part, knaves and parasites had the command of his fortune

然而支配他的家产的大多是恶棍和寄生虫。