力矢量

Characteristic vector which reflect tool wear condition is made of those characteristic parameters.

利用信号处理技术分析AE、Ac及切削力信号特征参数随刀具磨损的变化规律，并将这些特征参数组成反映刀具磨损状态的特征矢量。

Composition of Forces; The parallelogram Formula; Vector; High school student

中文关键词：力的合成；平行四边形定则；矢量；中学生

From an angle of engineering application, this paper dealt with the wavelet packets decomposition principle and its energy spectrum monitoring theory, which were used to extract the features of drilling force signals. Meanwhile, with an aim at the strong randomization and uncertainty characteristics between the feature vectors and drill wears in drilling process, a kind of drill wear monitoring method based on Hidden Markov Model was presented.

从工程应用的角度论述了小波包分解原理及其能量谱监测理论，并将该理论应用于钻削力信号特征提取中，针对钻削过程特征矢量与钻头磨损之间具有较强的随机性和不确定性的特点，提出一种基于隐马尔可夫模型的钻头磨损监测方法。

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。

As mentioned above, we have not explicitly used the first condition for equilibrium, that the vector sum of the forces be zero.

如上所述，我们没有直接应用第一平衡条件，即力的矢量和为零。

Velocity is a measurement of speed and has nothing to do with mass; however, force is a vector that is applied to the particle to change the particle velocity, and when it is applied, mass is taken into consideration (acceleration = force / mass).

速度是速率的衡量标准，它和物体的质量无关；然而力是施加在粒子上并改变粒子速度的一个矢量，当它施加在粒子上时，质量就成为要考虑的因素

By employing coordinate transformation, the overall generalized displacement vector relevant to the motion of pad and axle journal is converted into axle journal displacement vector in a local motion coordinate system, and the oil film force in a partial motion coordinate system is obtained by solving the dynamic characters of a fixed bush bearing.

通过坐标变换，将瓦块和轴颈运动相关的全局广义位移矢量转换为局部动坐标系下轴颈的位移矢量；利用求解固定瓦轴承动力特性的方法求得的局部动坐标系下的油膜力。

First, this paper presents three girders model with double cable planes which main girder and side girder is connected by rigid arms, analyzes the dynamic characteristic of Yonghe cable-stayed bridge and obtains its natural vibration modes (i.e., frequency, damping values and the mode shapes ) by ANLSIS structural analysis program and uses these parameters as dynamic dactylogram of the intact case of cable-stayed bridge. Using the passage of random as the ambient vibration ,the dynamic properties of Yonghe Bridge is measured and the modal parameter of its 15 years after is identified and used as dynamic dactylogram of the damaged case. By the finite element analysis and locale vibration test, damaged and undamaged modal parameter is analyzed and curvature mode shape, which is sensitive to damage state, is introduced as possible candidate for identifying and locating damage in the cable-stayed bridge. Selecting the branch of part measured point from modal parameter, this paper deduces the damaged index which can detect the possible damaged location of the cable-stayed bridge deck and identifies the damaged region and degree for Yonghe Bridge. For the purpose of structural condition monitoring in in-situ , from another viewpoint, this paper introduces the method called the best optimization vector to detect damaged location and degree. The accuracy and reliability of the method presented in this paper are demonstrated by static analysis and test and the healthy state of Yonghe Bridge can be evaluated.

建立了双索面通过刚臂与主梁及边梁相连的三梁式力学模型，采用ANSYS结构分析程序对永和斜拉桥进行动力分析，对其振动模态参数进行识别，以此作为斜拉桥完好状态下的动力&指纹&；采用自由交通流作为环境振源，对永和斜拉桥动力特性进行测试，识别出永和斜拉桥使用15年后的模态参数，确立了破损状态下的动力&指纹&；利用有限元分析、现场振动测试，对破损前后的模态参数进行分析，提取对破损状况较敏感的模态曲率作为斜拉桥破损诊断的参数；并从模态参数中选取部分点的分量，导出可以指示斜拉桥桥面大概损伤位置的Index损伤指标，识别出斜拉桥发生破损的区段及破损程度；考虑大型斜拉桥在线监测要求识别破损的具体位置，从另一角度提出采用最优矢量法具体确定破损发生的位置及程度；为验证本文研究成果，对永和斜拉桥进行静力分析及静力测试，对其健康状况提出可靠的评价。

The results show that with the increase of drill wears, the box dimension and the information dimension as well as the correlation dimension of drilling force signals appear obviously to have the downtrends. Accordingly, this characteristic can be effectively used to realize the monitoring of drill wears.Aiming at the characteristics of the highest overlap of the feature modes in each drill wear condition, the hidden Markov model is put forward to resolve the drill wear monitoring.

针对各钻头磨损状态下特征模式高度重叠的特点，提出采用隐马尔可夫模型HMM解决钻头磨损监测的思想，对1肠IM在钻头磨损监测中的原理及实现方法进行了系统的研究，完成了基于前后向算法和Baurn一Welch算法进行模型训练和识别的具体实施步骤，建立了基于S服网络的矢量量化器，解决了钻削力特征矢量的融合与编码问题。

"Force :Action that tends to maintain or alter the position of a body or to distort it. It is a vector quantity, having both magnitude and direction. Force is commonly explained in terms of Newton's laws of motion."

&力：力学中指任何使物体保持或改变位置或使物体变形的作用，力是一种矢量，有量值和方向，这一概念通常是按照牛顿运动定律所用的术语来解释的。&

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。