查询词典 arithmetic expression

Potential Species' Distribution System, a new GIS-based system, has been designed and implemented to predict the potential distribution of species by using presence data only. The result, normally overpredicted by traditional Environment Envelope Model, is improved by using hierarchical cluster arithmetic that can reduce the influence caused by outliers.

在这一系统中，通过层次聚类算法对物种已知分布点数据进行处理，减少了异常值对预测结果的影响，从而解决了环境包络模型预测结果过于乐观的问题，在物种已知分布数据较少时也能取得较好的结果。

By using the CFD software FLUENT, the inner-flow field of centrifugal fans with ruled-surface impeller versus with enveloping surface impeller has been simulated. The static pressure distribution, the dynamic pressure distribution, the total pressure distribution, the turbulent intensity and the speed vector of the two kinds of centrifugal fans are then analyzed and compared. From the calculating results, we found that the pressure distribution, the speed vector and other parameters of the two kinds of centrifugal fans are basically same. This implies that the tool-path generating arithmetic for the machining of the impeller can meet the aerodynamic requirements of the centrifugal fan. Furthermore the method can provide proof for designing department to establish sound manufacturing tolerance for impeller.

最后采用CFD软件FLUENT，利用标准k-ε湍流模型，采用分离隐式求解器，分别对直纹面叶轮离心通风机和包络面叶轮离心通风机整体风机内部三维流场和单个通道流场进行了数值模拟计算，在计算结果的后处理中，对相同坐标值处的静压力、动压力、湍流强度和速度矢量等参数进行了分析与比较，结果表明：在相同的计算参数条件下所得到直纹面叶轮离心通风机和包络面叶轮离心通风机内部流场差别不大，从而揭示所采用的叶轮数控加工的刀位规划方法的规划误差对流体机械动力性能的影响不大，这也为设计部门制定合理的叶轮加工公差提供了依据。

In other words combination of two arithmetic operations may produce rounding error that significantly exceeds 2 epsilon.

换句话说，两个操作操作的组合可能会产生显著超过 2 倍精度的误差。

Proving theorems in Coq is an interactive process: some decision procedures automate equational reasoning or Presburger arithmetic, for example, but most of the proofs consist in sequences of "tactics" entered by the user to guide Coq in resolving proof obligations.

在Coq中的证明定理是一个交互过程：比如部分判定过程可以自动完成等式推论或者Presburger算法，不过，更多的证明则是由用户输入用以指导Coq完成证明任务的tactics序列。

The signal test table is established where the Labview signal collection system collects the concrete exit pressure signals, the piston displacement signals of concrete cylinder and the main hydraulic signals. The real measured signals are processed through arithmetic equilibrant filter of the data signal processing method. The pumping efficiency and relative error of real time output are measured by two output calculation methods.

搭建了实测信号试验台，通过Labview信号采集系统现场采集混凝土出口压力信号、混凝土缸活塞位移信号和主液油信号，采用算术平均滤波法的数字信号处理方法对实测信号进行处理，通过两种排量计算方案检测泵车实时排量的泵送效率和相对误差。

At last, this paper introduces the PCB design and program arithmetic of the system, and solves the problem of error code.

最后，给出了无线监测模块应用中的电路设计和软件实现方法，并对通信中的噪声进行处理。

The account results demonstrate that this arithmetic is better than the usual regress method, the relative error is limit, and the prediction is reasonable. Therefore, it provides an effective method to solve nun-linear forecasting problem as waterway freight.

结果表明，本算法的计算相对误差很小，预测结果合理可信，且优于常用的回归预测，为解决航道货运量等非线性系统预测提供了一条新的途径。

This paper measures the fault vibration signal of the sun-gear in planetary gear box. Bring forward a new arithmetic of time-field average which settle the problem of cycle truncation error affect the result of averaging in substance.

但这些信号又往往被伴随产生的噪声干扰，在噪声较强时，不但信号的时间历程显示不出规律性，而且在频谱图上这些周期分量很可能被淹没在噪声背景中。

In this paper the effects of scanning truncation error, scanning position error, random amplitude and phase error, and multiple-reflection error in near-field antenna measurement are analyzed; error equations and the uncertainty of measurement are obtained through computer simulation; compensated techniques for reducing the effects of measurement errors in near-field antenna measurement are presented and the formula and arithmetic of phaseless near-field techniques are derived.

本文从解析法和数值仿真两个角度深入分析口面天线近场测量中扫描面截断误差、扫描面位置误差、随机幅相误差、多次反射误差等误差源对天线远场特性测量精度的影响，一方面从理论上给出相应的误差方程，另一方面建立误差分析模型，通过计算机模拟，得到不同误差条件下测量结果的不确定度，并介绍了减小这些误差的修正方法，推导无相位近场测量的公式和算法。

Value.h completely hides the evaluator for arithmetic expressions and at the same time specifies what we have to implement.

识别器完成了。value.h完全隐藏了数学表达式的求值程式，同时也指定了我们必须要实现的函数。

The role of the environment is very important.

的作用，环境是非常重要的。

At that time, the High Court of England and Wales Court of Queen's Bench president of William Murray, Lord Mansfield in June 22, 1772 ruling:"No matter then there is the inconvenience, but there must be a decision, I can not say that this case under the law in England are permitted or authorized; are so black should be released."

当时的英格兰及威尔士高等法院王座法庭院长William Murray， Lord Mansfield于1772年6月22日宣判：「无论有那麽不便，但总要有个决定，我不能说这件案在英格兰法律之下是准许或认可；所以黑人是应该被释放。