摩擦力

A novel optimal robot dynamics identification strategy was present through analyzing the characteristics of nonlinear dynamic friction at the joints.

通过分析关节的非线性摩擦力的特点，提出了一种新颖的机器人动力学模型识别途径。

The results show that the microstructure of ventra1 scale for python was composed of micro-convex and plank structure that was periodically arranged, it was mensurable and could be described by 9 characteristic parameters. Its surface was different in their forward and backward lean angle. The frictional coefficient of the ventra1 scale had closely relationship with moving direction, it decreased with the increasing load. The value of the frictional coefficient was about 0.07. The frictional coefficient while python moved backward and laterally were equal, and that was 33% more than that moved ahead. The frictional force of the ventra1 scale surface was caused by mechanical tooth function of micro-convex, acting intermolecular force and material's elastic hysteresis. The difference of forward and behind bevel for micro-convex was the anisotropy reason of frictional force.

结果表明：腹鳞表面的微观结构由指状微突体和板结构部分周期排列而成，其结构可用9个特征参数定量描述；腹鳞表面摩擦力由分子作用力、表面微突体的犁沟力、楔形作用力以及材料弹性滞后共同引起；腹鳞表面的摩擦系数在0.07左右并与运动方向有关，摩擦系数随载荷增加而减小；后向运动及左、右侧向运动时摩擦系数基本相等，比前向运动时高33%左右；腹鳞表面微突体不同方向上倾斜角度的差异是引起摩擦各向异性的主要原因。

Use emery paper to rub your soles so as to increase the friction between ?

一：用砂纸磨擦鞋底，增加鞋底与地面的摩擦力。

There is no complexity here because it is natural; it is with the grain, where the friction of effort is removed from the task and because of the incoming energetics of our time, the task is even simpler.

这里没有复杂性，因为这是自然的。顺着事情走，所做努力的摩擦力才会从任务中消失。而且因为我们这个时代的正来临的能量学，这个任务甚至更简单。

Due to friction , this part of the input energy is wasted.

既可指客观因素，也指主观因素11 由于摩擦力，输入能量的这一部分被浪费了。

At present, although finite element methods is a kind of effective measures in analyzing metal plastically forming problems with friction, dynamic friction in the process of metal forming is substituted with static friction and constant frictional force as one of independent constraint conditions is transposed to equivalent node-load or FEM unit is divided into contact unit and inner unit in numerous studys and applications, so that it result in relative bad accuracy and awkward operation. These defects mostly attribute to the fact that FEM bases on the variational equality principles, however frictional constraint will actually result in variational inequality energy functional.

目前，应用于分析金属塑性成形的有限元法是一种有效的处理摩擦效应的定量计算方法，但是许多应用和研究是用常摩擦来代替金属塑性成形过程中的动态摩擦；把常摩擦力作为单独的约束条件移置到等效结点载荷上或把有限元单元划分成接触单元和内单元，这些将导致解的精度相对不高及实际操作不方便等一系列问题，产生这些不足的重要原因之一在于它的理论基础是变分等式原理。

Studying from dynamic hydraulics, in consideration of the friction impact, differential equation of motion and equation of continuity have been established, from which transient velocity equation and pressure fluctuation equation describing viscous fluid micro-vibration inside of a string have been deduced out.

从动态水力学的角度出发，建立了考虑摩擦力影响的流体运动微分方程和连续性方程，得到了具有粘滞性流体在管柱内微振动时的瞬态速度和压力波动方程。

In this method it is assumed that when the rail is bent downward, it will be subjected to the reactive force of elastic support points, and when bent upward, the rail will sustain the reactive force of the fastenings (i.e.the weight of sleepers and the friction between sleepers and ballast).

其中假定钢轨向下挠曲时所受的是支点反力；向上挠曲时所受的是扣件反力(由于轨枕自重和轨枕与道床的摩擦力)，这两种反力按上下方向以不同的非线性关系依赖于钢轨位移。

A paradox of work done by friction is clarified, and the general format of principle of energy-work and the first law of thermodynamics are presented.

本文澄清了一个关于摩擦力做功的佯谬，并提出了功能原理与热力学第一定律的一般形式。

The force of gravity and the friction of the air near the earth are working against the satellite.

在地球附近的重力和空气中的摩擦力影响工作中的卫星。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。