数学

A real number is said to be a rational number if it can be expressed as the ratio of two integers, where the denominator is not zero.

这是定义数学术语的一种形式。下面是另一种定义数学术语的形式。

If we rechange these two numbers: one number to two times as many as its original value, and the other to four times as many as its original value, the average of the five numbers will become 13. Which two numbers have been changed?I only know that the total sum of the original numbers is 45(5×9), the total sum of the 5 numbers after the first change is 40(5×8), and the total sum of the 5 numbers after the second change is 65(13×5). What can I do next? Please help me with the problem.Thank you!

这就要求琬婷一方面要用英语准确地把她想要问的问题清晰地表达出来，只有这样网上"数学博士"才能明白你要问的问题；另一方面琬婷还必须能够正确理解网上"数学博士"对她所提问题的英语答复，这两者是相互依赖的，否则就不能正确地帮助你理解和解决问题，这就要求琬婷必须用英语进行正确地表述和理解。

The results show that in the internal standard method the mathematical treatment of uniform distribution of NG in deterred layer has no effect on the order of magnitude of the diffusion coefficient, so the systematical deviations of the reconcentration profile obtained from the imperfection of calibration model can be neglected.

内标法与外标法的比对实验结果表明，在内标法中将钝感层硝化甘油做均匀分布的数学处理对扩散系数计算结果的数量级没有影响，因此由于数学模型的不完善带来的浓度分布曲线的系统偏差可以忽略不计。

Research methods: The comparison was made between regression analysis and curve's fitting by adopting comparison method.

用数学模型的形式表现劳动定额是通过数学方法和计算机实现劳动定额管理现代化的一种新的方法。

What sets DataFit apart from similar curve fitting and regression programs is its ease of use.

软件已内置上百个数学模型，并可由用户自己设定数学模型，对于初学者和专家来说，该软件都是一个高效率的易于使用的曲线拟合和分析的工具。

In this paper, firstly, the lubrication and wear-resisting mechanism of the surface with regular micro-structure is studied and the corresponding lubricated theory model is also developed. And then, use modified multi-grid method to solve the theory model, and cylinder wall surface micro geometry shape parameters are designed and optimized.

本文首先通过研究具有规则微观几何形貌表面的润滑、减磨机理，建立相应的缸套—活塞环摩擦副润滑理论数学模型，利用变异的多重网格法求解此数学模型，对缸套表面微观几何形貌设计参数进行优化匹配。

The Chinese Remainder Theorem is one of the greatest achievements in the Chinese traditional mathematics,which is on the theory of congruence of first degree. It's from the problem of the "Wu Buzhishu" in the Chinese classical mathematical work Sunzisuanjing.

"中国剩余定理"是中国传统数学中关于一次同余式理论的一项杰出成就，它源于中国数学典籍《孙子算经》中的"物不知数"问题，秦九韶在《数书九章》(1247)中将这一问题发展为求解一次同余式组的一般方法，称为"大衍总数术"。

The research results show that renewal theory can be used to direct the policymaker of the vehicle maintenance and repair and it is very effective to simplify the mathematical models and the solutions to the models.

研究结果显示：更新理论完全可用于指导车辆的维修决策，而且对简化问题的数学模型及模型的解非常有效；运行试验的验证结果表明，基于更新理论和更新函数所建立的车辆最优维护周期数学模型的解是准确、可靠且符合实际的。

In this paper, the mathematical models, the numerical methods and the kinetic mechanism were systemically studied and improved to meet the requirement. The renormalization group k-εturbulence model was adopted to simulate in-cylinder flows in this article.

本文在三维数学模型中嵌入了化学动力学反应模型，构建了能够深入研究天然气燃烧反应机理、了解天然气发动机燃烧过程的数学模型。

Moreover, it also breaks a new field of engineer research in fuzzy mathematics: multidimensional fuzzy mathematics.

与此同时，也为模糊数学开辟了一个新的工程研究领域——多维模糊数学。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。