查询词典 isochronous curve

In the last chapter, by introducing the isochronous center of real systems into complex planar and defining complex center and complex isochronous center, a concise linear recursion formula for period constants is given, necessary and sufficient conditions of complex isochronous center (the Time-Angle Difference Theorem) proved, conditions of real systems with linearizable center and saddle treated unitedly and the isochronous center conditions discussed fully for a class of real planar cubic systems.

在第七章，通过把实系统等时中心引入复平面研究，定义了复中心和复等时中心，给出了等时中心周期常数计算的简明的线性递推公式，证明了等时中心判定的充分必要条件，统一地处理了实系统具有可线性化的中心和鞍点条件，并对一类实平面三次系统的等时中心条件进行了完整研究。

In this paper, a region approximation idea that means using a "fat curve" with a width to approximate the offset curve is proposed, and a complete set of algorithms to approximate offset curve using disk Bézier curve are given and implemented. In the algorithms, the optimal and uniform approximate curve of the offset curve as the central curve of the Disk Bézier curve is found by using Remez method, and then the upper optimal and uniform approximation principle is proposed to compute the error radius function of the Disk Bézier curve. Thus, the whole Disk Bézier curve can be obtained. In the end of this paper, the approximate effect of the Disk Bézier curve is not only analyzed and assessed, but also some specific examples are provided.

提出用一条带宽度的"胖曲线"来逼近上述等距曲线的区域逼近思想，并建立与实现了圆域Bézier曲线等距逼近的整套算法，包括应用Remez方法求出等距曲线的最佳一致逼近曲线作为圆域Bézier曲线的中心曲线，提出上控最佳一致逼近的原理求出圆域Bézier曲线的误差半径函数，以及确定整条圆域Bézier曲线，最后还对该圆域Bézier逼近的效果做了分析和考核，并给出了一些具体实例。

This paper establishes cubic spline function, analyzes subsection curve function and curve slope and curvature, at last decides to place the curve especial points which can be obtain easement curve length and other line parameters, such as the ZH point (end of line and beginning of transition curve), the HY point (end of transition curve and beginning of circular curve), the QZ point, the YH point (end of circular curve and beginning of transition curve), the HZ point (end of transition curve and beginning of line).

针对公路平面线形的8种组合类型，其线形元素特征则由最基本的直线、圆曲线、缓和曲线组成的特点，解析三次样条函数模型，得分段曲线函数、曲线斜率、曲率，从而确定曲线特征点（直缓ZH点、缓圆HY点、曲中QZ点、圆缓YH点、缓直HZ点）位置，进而得到曲线缓和曲线长度及其他线形参数。

At last, the isochronous center of infinity of a class of quintic systems is studied and all conditions of center and isochronous center are obtained for infinity of this system, which is the first time for the research on the isochronous center of infinity.

最后，研究了一类实平面五次系统的无穷远点的等时中心，给出了系统无穷远点为中心和等时中心的全部条件。这是迄今对无穷远点等时中心进行的首次研究。

With increasing loading, the reduction degrees of average correlative coefficients of linear fitting functions of isochronous stress axial strain curve and isochronous stress-radial strain curve are 0.97% and 0.67% respectively, which indicates the linear correlation decreases commonly.

随加载应力水平的提高，应力－轴向应变等时曲线和应力－径向应变等时曲线线性拟合函数的平均相关系数下降幅度分别为0.97%和0.67%，线性相关性普遍降低。

The average correlative coefficients of linear regression function for isochronous stress- axial strain curve are 3.92% higher than that of average correlative coefficients of linear regression function for isochronous stress- radial strain curve, so nonlinear creep property of the fine sandstone specimen in axial direction is correspondingly weaker than that in radial direction.

应力－轴向应变等时曲线线性回归函数的平均相关系数高出应力－径向应变等时曲线线性回归函数的平均相关系数3.92%，因此其轴向非线性蠕变特性相对于径向非线性蠕变特性更弱。

Based on formers criteria of isochronous centers for centers, we analyze parameter conditions of isochronous centers.

在此基础上，还在前人获得的多项式Liénard方程的等时中心判据的基础上，进一步分析了等时中心的参数条件。

Finally it analyzes the feasibility that using hydromechanics to analyze traffic flow by contrasting various characters between traffic flow and fluid flow. It analyzes influence of road alignment to basic expressway segment capacity by hydromechanics, and obtains viscous resistance and viscous movement differential equation when the vehicle drives on circular curve segment of expressway. And it infers that viscous resistance is correlated with sideway force coefficient, slope of crown and radius of circular curve. Radius of circular curve, sideway force coefficient and slope of crown are bigger, viscous resistance is smaller, the influence to capacity is smaller when the vehicle is running on nearside lane of circular curve; but radius of circular curve and sideway force coefficient are bigger, slope of crown is smaller, viscous resistance is smaller, the influence to capacity is smaller when the vehicle is running on fast lane of circular curve.

最后通过对比交通流与流体流的相似性，运用流体力学分析了道路线形对快速路基本路段通行能力的影响，求出了车辆在曲线路段的粘性阻力，建立了车辆在曲线路段的粘性运动微分方程，并由此推知，粘性阻力与横向力系数、路拱横坡度和圆曲线半径都有关系，当车辆在圆曲线外侧车道上行驶时，圆曲线半径、横向力系数和路拱横坡度越大，粘性阻力就越小，对道路的通行能力影响就越小；而当车辆在圆曲线内侧车道上行驶时，圆曲线半径和横向力系数越大，路拱横坡度越小，粘性阻力就越小，对道路的通行能力影响就越小。

Result: Scoliosis was identified in 58 cases with Marfan syndrome (38 males and 20 females), the prevalence rate was 42.03%, male-female sex ratio was 1.18:1, 6 cases were in younger than 10-year-old group. 12 cases were in 11~20-year-old group, 19 cases were in 21~30-year-old group, 11 cases were in 31~40-year-old group, 7 cases were in 41~50-year-old group, 3 cases were in 51~60-year-old group. Mean magnitude of Cobb angle in coronal plane was 26.8°±27.8°, the types of scoliosis curve included thoracic curve (36 cases), thoracolumbar curve (11 cases), lumbar curve (2 cases), double curve (6 cases) and triple curve (3 cases), apex vertebraes were convex to the right side among single curves in 38 cases while 11 cases were convex to the left side. Mean magnitude of kyphosis in sagittal plane was 14.3°±13.2°, 5 patients had thoracic lordosis and 40 patients had hypokyphosis and 12 patients had normal kyphosis.

结果：58例(42.03%)患者合并脊柱侧凸，男38例，女20例，男女患病率比例为1.18：1，其中≤10岁6例，11~20岁12例，21~30岁19例，31~40岁11例，41~50岁7例，51~60岁3例；平均冠状面Cobb角为26.8°±27.8°；胸弯36例，胸腰弯11例，腰弯2例，双弯6例，三弯3例；单弯中顶椎凸向右侧38例，凸向左侧11例；矢状面胸椎后凸平均为14.3°±13.2°，其中胸椎前凸5例，胸椎后凸不足40例，胸椎正常后凸12例，仅1例胸椎后凸45°；11例患者冠状面Cobb角＞40°，平均年龄15.9岁。

From a neutral gray balance curve, the curve Y, m, and the basic coincideut from neutral gray balance curve, the curve Y, m, and C coincideut basic curve the Y, m into a bow-shaped curve.

而从洋性灰不均弧线来看，Y、M弧线根基重分，而从洋性灰不均弧线来看，Y、M弧线根基重分，而C弧线则矮不入Y、M成为一条弓形弧线。

The dissecting of samples in group2 were difficult. The root of pulmonary artery and ascending aorta failed to be unfolded because fibrous tissue was tough, right and left fibrous trigone were too firm to be solved by hand. Cardiac muscle fibers couldn't be stripped along myofibrillar trajectory since they were prone to break because of their friability.

组2的心脏解剖困难，表现为纤维组织坚韧，游离肺动脉非常困难；徒手无法松解左、右纤维三角，肺动脉和主动脉根部的游离非常困难；心肌纤维坚硬、质脆，解剖时容易断离成碎块，无法沿纤维走行方向剥离。

We have battled against the odds in a province that has become increasingly violent.

我们对在一个争夺日益激烈省的可能性。