对数

The automatic generation of logarithmic spiral is achieved by means of the language of VBA embedded in AutoCAD.

提出铲齿成形铣刀齿背曲线的最佳线形应是对数螺线，而后运用AutoCAD的内嵌编程语言VBA，实现了对数螺线齿背曲线的自动生成。

The correctness lays a theoretical foundation on further study of the processing technology of logarithmic spiral bevel gear, and thus, the new-style bevel gear can be machined conveniently and quickly.

证明了对数螺旋锥齿轮啮合原理的正确性，为进一步研究对数螺旋锥齿轮的加工工艺提供了理论基础，进而可以实现这种新型锥齿轮的方便快捷的加工。

So,lognormal distribution is not the well life distribution of thismaterial.

结果表明，通常采用的对数正态分布的理论失效率呈单峰型，与材料经验失效率的变化不相一致，因此对数正态分布不宜作为稀土钼铜合金球墨铸铁材料裂纹萌生寿命的概率分布。

Using inverse function to generate exponential distribution random number, introduce new algorithm, namely Maclaurin Equation, which is easy to be implemented by Hardware, use Maclaurin Equation to extend the function of Logarithm, make it compose by addition, division and multiple.

对于反函数法产生指数分布的随机数，提出易于硬件实现的算法结构——麦克劳林展开法，先用麦克劳林展开式展开对数函数，把对数函数转换成一系列乘、加、除运算。

We study it, in order to understand the application of mathematical formula in physics and chemistry more deeply.

在物理学上，有许多重要的物理量间的关系如大气压强随高度的变化关系，分子松弛运动与时间的关系等，均可用指数关系式或对数关系式来表示；在化学中，特别是化学反应速度与温度的关系，化学平衡常数随温度的变化等，通常也可用指数关系式或对数关系式来表示。

Furthermore, the kernel density estimation, a nonparametric method, is used to estimate the density functions of natural logarithm of average cost per stay and average days of inpatient.

此外，本文将非参数模型中的核密度估计方法应用于每次住院费用对数和每次住院天数对数的分布研究中，并用它进一步估计了每次住院费用和每次住院天数的均值和方差，取得了较好的效果。

Natural logarithm of conditional odds of dependent variables are called logit.

洛基对数线陆模式系以依变项的条件胜算之自然对数为分析单位。

The negative binomial distribution, gamma distribution, and log-normal distribution were chosen as error distributions according to log-linear regression of variance versus log-mean of CPUE.

根据鲐鱼单位捕捞努力量渔获量数据呈正偏，以及CPUE均值与方差在对数尺度下的线性关系，选择了负二项分布、伽马分布与对数正态分布作为误差分布。

I have calculated the species diversity for 3 layers (i.e. tree layer, shrub layer and herb layer) by means of various biodiversity index formulas and analyzed the relative species abundance using 9 models of the probability density distribution functions, such as, 3 Distribution (or Beta Distribution, Weibull Distribution, Lognormal Distribution, Poisson Distribution, Binomial Distribution, Negative Binomial Distribution ,Geometric Distribution, etc.. chi-square analyses were conducted on species distribution by using the chi-square test formulated by Pearson to test which distribution function is better, the result of chi square test made it possible to reject the other 8 distribution functions, theβdistribution function performs better than other probability density functions, it has a very close approximation, which can be used for the description of relative abundances of species in forest communities in this data set.

在相对多度研究上选用了九种概率分布模型，这九种概率密度分布函数依次为：贝塔分布、Weibull分布、对数正态分布、泊松分布、二项分布、负二项分布、几何分布、对数分布和奈曼A型分布，并进行了严格的卡方检验，结果表明：其它八种分布均被遭到拒绝，只有贝塔分布获得了通过，且拟合的结果非常理想。

Not one number, but a pair of numbers corresponds to every point on the plane; a definite point corresponds to every pair of numbers.

和平面上每一点相对应的不是一个数而是一对数，一个确定的点都有一对数跟它相对应。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。