Those sensitive parameters making system have negative damping and occur self - excited shimmy are horizontal pulling lever rigidity , tire sideslip rigidity , steering gear rigidity and damping , kingpin equivalent damping , kingpin caster angle , tire drag . and wheel center distance , tire side rigidity , vehicle wheel unbalanced mass , tire vertical rigidity , and distance from kingpin center to the vertical central line plane of tire have great influence on shimmy , but they do n ' t make the system have negative damping . and horizontal pulling lever damping , suspension damping and rigidity have very small influence on shimmy 横拉杆刚度、轮胎的侧偏刚度、转向机刚度、转向机阻尼、绕主销当量阻尼、主销后倾角、轮胎拖距是影响摆振的敏感性参数，适当调节某一参数可引起系统的负阻尼，使系统产生自激摆振；轮距、轮胎侧向刚度、车轮上的不平衡质量、轮胎垂向刚度及主销延长线与地面交点至车轮平面的距离对摆振的影响也较大，但不会使系统出现负阻尼；而横拉杆阻尼、悬架阻尼与悬架刚度对摆振的影响很小。
The academic gist of " catching up with and surpassing " is the theory of " advantage of backwardness " . the american economic historian alexander gerchenkron did theoretic research on the topic at an earlier time , but his research was developed on the extended line of economic development history of great britain and developed areas of europe continent , the research objects were limited only to the european countries 较早研究后发优势理论的是美国经济史学家格申克龙，但他的研究是在英国以及欧洲大陆发达地区经济发展史的延长线上展开的，研究对象仅限于比英国工业化起步时间较晚、经济发展较为落后的欧洲国家。
The time - related expression of stain along the crack - tip extension line was given from the use of the elastic - viscoelastic correspondence principle and standard linearity body model and the non - linear factors , which caused the gradual difference between the theoretical and actual value with the increase of time , were analyzed 应用广义弹性?粘弹性对应原理，给出了线粘弹性体裂尖延长线应变值随时间变化的表达式，分析导致理论与实验情况随时间增加产生偏差的非线性因素。
To build the basic frame as “ one river two lines and one road ” for the center city , namely extend the tongzhou center city the toward the east and the south , the 40 square kilometer etended to 80 square kilometer , can accommodate 600 thousand people , taking one river ( the northern canal ) , two lines ( chang1an street extending line , badaling - tongzhou line ) and one road ( the sixth circle line ) as the frame , with the city part of the canal as the axis , the new city square as the center , relying on the symbolic sights belt of the canal and the wenyu river and the city economy , making tongzhou as a modernizational and international shore city with old city revised and improved , the new cities promptly emerging , high quality and prominent characters , and with the water , the greenbelt and the modernized city sights as the city ' s main characters 构筑中心城“一河两线一路”的基本框架，即通州中心城将在现有的基础上向东南方向拓展，由现有40平方公里扩大到80平方公里，能容纳60万人口，以一河（北运河） 、两线（长安街延长线、八通线） 、一路（六环路）为架构，以运河城市段为轴线，以新的城市广场为中心，以运河、温榆河标志性景观带和都市经济为依托，是一个旧城得到改造提升，新城迅速崛起，具有高品位和鲜明特色，以水、绿和现代城市景观为主要特征的现代化、国际化的滨水城市。
