对圆的

Based on varying process of generator terminal parameters after excitation fault, shortages of excitation protective principle of static stability boundary and asynchronous impedance boundary are analyzed. It proposed that excitation fault research relates to large-disturbance stability. Because dynamic power-angle character of generator after excitation fault is non-sinusoidal, there are differences between dynamic power-angle character and static state power-angle character. So it isn't ideal to protective operation result based on small-disturbance stability and static stability boundary criterion. At the same time, it proposed that asynchronous boundary impedance criterion is a constant reactive power circle moving adown j Xd′. It can ensure complete loss-of-excitation generator measuring impedance enter into the circle, but can't ensure the other condition measuring impedance including impossible losing synchronism enter. So loss-of-excitation protection would be maloperation when system voltage drops short and recovers or generator rejects load.③Based on stability principle, it puts forward setting conditions and calculation method of generator loss-of-excitation protection by direct measuring power-angle.

以励磁故障后发电机端的相关参数的变化为基础，通过对以静稳定边界和异步阻抗边界作判据的两类三种现行励磁保护在原理上存在的缺陷分析，发现：励磁故障是一个大干扰稳定性问题，励磁故障后的发电机的动态功角特性与静态功角特性有很大的差异，已远非正弦曲线，因此基于小干扰稳定性原理、以静稳定边界作判据的保护必然动作不理想；异步边界阻抗判据是一个下移j Xd′的等无功阻抗圆，它可以保证完全失磁后的发电机测量阻抗能进入该阻抗圆，但不能保证完全失磁之外的其它状态不会进入该阻抗圆，因此在系统电压短时下降或发电机突然甩负荷等情况下可能启动该保护使之误动。

In order to analyze the vibration characteristics of the high speed dick system,which was an important component of the submuniton angular motion hardware-in-the-loop simulation,the mechanics model was firstly derived.

为了分析子弹角运动半实物仿真装置中快圆运动系统的固有频率及其对整个装置的影响，利用La-grange方程建立了快圆运动系统的动力学方程，得出该系统的质量矩阵和刚度矩阵，对其进行模态分析；同时利用有限元软件仿真，验证了理论分析结果。

The flexural vibration of a circular ring that is of axis symmetry is analyzed and calculated, the solid frequency expression of the flexural vibration is obtained.

对一类轴对称圆环的面内弯曲振动进行了分析计算，给出了圆环面内弯曲振动固有频率表达式。

Experimental results show that guard ring can postpone the collision region shell to rupture.

实验结果显示：在紫铜圆管对碰部位增加保护环结构，可以有效推迟该部位圆管的破裂时间。

Constraint equations are derived to improve the original circle detection algorithm, which based on right triangles inscribed in a circle.

建立了条件约束方程组对基于圆内接直角三角形的圆检测算法加以改进。

The evaluation method and algorithm of shape error (roundness, plane straightness, space straightness, cylindricity) were discussed. A new kind of algorithm, namely mesh searching method, which can be used to evaluate the roundness error, plane straightness error, space straightness error and cylindricity error, were put forward. With this algorithm, the shape error can be obtained by transferring the distance formula repeatedly and simple judgment without linearzing the distance formula (from point to point or point to line) and choosing optimal direction and step length.

对形状误差(圆度、平面直线度、空间直线度、圆柱度)的评定方法及算法进行了讨论，提出了一种评价圆度误差、平面直线度误差、空间直线度误差及圆柱度误差的新算法——网格搜索法，该算法不需要对距离公式线性化，也不需要选定优化方向和优化步长，只需重复调用距离公式和简单的判断即可得到符合定义的形状误差。

Researches are made to find out the active tracing measurement strategy of crankshaft roundness error during noncircular grinding process .

本文对曲轴连杆颈非圆磨削过程中圆度误差的在线跟踪测量策略展开研究，推导了测量系统跟踪运动方程，针对在频域分析时对3个传感器之间线性相关性的要求，论述了满足均匀采样的约束条件。

Modeling and derivation mathematics result of the use of Matlab software Simulation tests of its accuracy and error analysis, to verify the measurement of two boring bar/boring displacement signal the feasibility of the entire system, so as to the smooth development has laid a theoretical foundation.

介绍了两点法测量镗刀位置信号的方案构思，采用最小二乘法对镗杆的圆度误差和被测圆面的偏心量进行了建模计算，并对数学推导的结果利用Matlab软件进行仿真检验，对其精度和误差作了分析，验证了两点法测量镗杆／镗刀位移信号的可行性，从而为整个系统的顺利开发奠定了理论基础。

According to topographic information of Dongyang and Wanshou which are tentatively chosen as the sites to assemble grounding poles,the selection of d/D ratio,namely the ratio of radius of two adjacent toroids,of standard triple toroidal grounding poles,the burial depth characteristics of each sub-toroids and the feasibility of adopting such type of poles are researched.

分析了直线形、星形和圆环形3种常见水平接地极的特点，结合溪洛渡、向家坝直流换流站初选东阳和万寿极址的地形资料，对标准3圆环接地极的环径比例选择、各子圆环的埋深特性及采用该电极型式的可行性进行了分析研究。

In this paper, we proved that there exists only one contact point between a pair of non-circular gears working under the designed pitch curves when they are manufactured by involute cylindrical gear cutter in numeric control slotting machine. Under this manufacturing condition, the pair of non-circular gears can mesh accurately.

证明了采用渐开线圆柱齿轮刀具在数控插齿机上加工的1对非圆齿轮副传动时，在其按设计的已知节曲线工作时，两非圆齿轮副的齿廓具有单一的接触点，即能保证正确的啮合关系，为深入分析非圆齿轮副的传动机理提供了前提。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。