The reasons to choose aspherical grads method as the principle were presented . the two spheres which were gotten from aspherical grads method and least square method were analyzed by fem software , and the deviation with the wanted aspherical surface and the maximum stress were compared under same confined condition , same loading position and loading points . also , we proved that the sphere gotten from aspherical grads method has less surface error and stress after deformation 用有限元软件分别对非球面变化梯度法和最小二乘法所获球面进行了分析,比较两种球面在相同边界条件、相同加载位置和个数下,与所需非球面的面形误差和应力的大小,证明了用非球面变化梯度法所获得的球面在变形后,面形精度更高,应力更小。
By analyzing the topology of an interconnected power system , chapter 3 of this thesis derives the spanning tree , and builds the corresponding minimal cut set . by combining the results from the graph theory with the reliability indices of the individual reparable components , the reliability indices at the load point can be obtained , and the reliability indices for the whole system are deduced 本文的第三章从单个可修复元件的可靠性指标出发,在分析电网络的拓扑结构的基础上,利用一定的算法求出其对应的生成树,根据生成树和最小割集之间的对应关系,得到整个电网络的最小割集。
Firstly , reliability models of different element are built in the paper . secondly , the reliability parameters of virtual series element on the main feeders are computed by series equivalent method . lastly , indices of different load points are calculated by the method of minimal cut - set 文中首先建立了不同元件的可靠性模型,其次通过串联等值法求取各主馈线上的虚拟串联等值元件的可靠性参数,最后应用最小割集方法计算各负荷点指标,从而得到系统各项可靠性指标。
The optimization results show that the effective interfacial area hi three - phase distillation is much bigger than the prediction of correlation when the operation condition is above the loading point , while no such phenomena are found when the operation condition is below the loading point . 5 . the experiments reveal that almost 21 % reduction in the 5 .实验结果表明三相精馏过程在载点之前的分离效率比两相精馏过程的分离效率低21 % ,而在载点和泛点之间,三相精馏过程的分离效率则比两相精馏过程的分离效率高了近51 % 。
As soon as the normal section cracks , the crack firstly appears in the flexural region . at this moment , the load - deflection curve has a turning point . with the increase of the load , the rigidity of the beam decreases compared with that before cracking because of the development of cracks in flexural region , and the formation and development of diagonal cracks toward the loading point , the load - deflection curve is basically linear till the beam fails 正截面开裂前,荷载挠度曲线基本为线性,截面刚度较大;正截面开裂时,裂缝先在纯弯段出现,荷载挠度曲线出现转折点,随着荷载的增加,纯弯段正裂缝的发展以及剪跨段斜裂缝的产生并向梁的受压区加荷点发展,使梁的刚度较截面开裂前减少,荷载挠度曲线也基本为线性直到梁破坏。
This thesis discussed the affection of all kinds of components contingency and the components " position in the line and other factors on the evaluation of load point reliability index . this thesis adopts a integrative method to deal with simple or complex distribution network with the system ' s practical operation characteristics and the results of the example reveal that it is feasible . the key to study the economics of power system reliability is outage costs 在定量评估负荷点或系统可靠性指标的研究中,本文较全面地分析了各元件故障和元件在线路中的位置以及计划检修、临时停电、天气因素、负荷转移等因素对估算负荷点可靠性指标的影响;研究了现有的可靠性评估模型,结合城市电网的实际运行特点,采用一种综合的方法估算辐射型电网的可靠性指标,算例结果表明它是有效可行的。
The practical situations of system operations are considered in this paper . based on the enumeration of the cut sets for the load point interruption , load transition character , maintenance of devices , active failure mode and overload of transmission line are all discussed . the evaluation is more realistic and effective 该方法充分考虑了系统运行的实际情况,在列举引起负荷点供电停止事件割集的基础上还考虑了负荷点供电的转移特性,网络元件的计划检修和活动性故障,以及系统运行的过负荷约束等诸多情况,使评估过程更加合理和有效。
By using the presented method , the number of nodes having a hand in the iteration is obviously reduced ; and the voltage at each load point and the line losses of distribution network can be directly obtained without iteration ; thereby the line losses of the whole distribution network can be accurately determined 该方法的计算精度比较高,可大大减少参与迭代计算的节点数,而且各负荷点的电压以及配电网的线损不需迭代就可以直接计算得到,从而精确得到整个配电网的线损。
8 ) the aas scheme has the property of maintaining the mechanical equation , smoothness controllable , has lifting scheme and easy , fast calculation . 9 ) in the processing of correlation visualization , the voronoi diagram and the delaunay triangulation had been introduced for the first time , and use them as the bases of defining the topology of the scattered load points , calculating the correlation and filling the color 5 )在将节点间的相关性进行三维可视化处理的过程中,首次引入了voronoi图和delaunay三角形,作为确定散乱加载节点间拓扑关系、计算相关性和根据相关性大小填色的依据,实现了节点间的相关性的三维可视化。