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本文论述了不解算GPS基线,而直接解求三维变形量的原理及正确性的验证,介绍了研制的Gquicks1.5版本软件系统流程及主要功能模块。通过在三峡库区GPS滑坡监测实践的应用,总结了GPS观测纲要,提出了一些有益的结论与建议。 相似文献
214.
由于AutoCAD中没有专门绘制三维深沟球轴承命令,因此采用二次开发的方法可迅速绘制所需的三维轴承.该方法采用V isual LISP语言编制程序进行二次开发AutoCAD三维深沟球轴承绘制方法的功能,为AutoCAD新增绘制三维深沟球轴承功能的命令,使得在进行机械产品三维CAD时,绘制三维深沟球轴承更为方便,提高三维设计的绘图工作效率. 相似文献
215.
LI Yue YANG Baojun YUAN Ye ZHAO Xueping LIN Hongbo 《科学通报(英文版)》2006,51(24):3010-3017
Taking the advantage of CVS (Chaotic Vibrator System) sensitivity of large-scale periodic phase-state response to quasi-periodic or periodic signals,a series of numerical experiments were made to understand the ability of CVS to detect weak effective seismic signals in the common-shot seismic record distorted by strong stochastic noise. The re-sults demonstrate that the large-scale periodic phase-states of CVS are correlated with the signal composition of the quasi-periodic wavelet sequence constructing from horizontal moveout of seismic events,noise strength and the noise distortion de-gree to signal. For the same kind of events,the higher the noise distortion degree is,the lower the detectable SNR can be reached by CVS. For seismic data with the same noise distortion degree,the closer the scanning seismic velocity (the trial moveout ve-locity) approaches to the accurate velocity,the higher the detectable SNR can be reached by CVS. More-over,the truncating scanning velocities form an asymmetric belt,which indirectly makes CVS achieve a large-scale periodic phase-state and then the ratio of wavelet distortion coefficients in events can be a biggish variable scope. 相似文献
216.
An approach to 3D NURBS modeling of complex fault network considering its historic tectonics 总被引:1,自引:0,他引:1
Fault disposal is a research area that presents difficulties in 3D geological modeling and visualization. In this paper, we propose an integrated approach to reconstructing a complex fault network (CFN). Based on the non-uniform rational B-spline (NURBS) techniques, fault surface was constructed, reflecting the regulation of its spatial tendency, and correlative surfaces were enclosed to form a fault body model. Based on these models and considering their historic tectonics, a method was put forward to settle the 3D modeling problem when the intersection of two faults in CFN induced the change of their relative positions. First, according to the relationships of intersection obtained from geological interpretation, we introduced the topological sort to determine the order of fault body construction and rebuilt fault bodies in terms of the order; then, with the disposal method of two intersectant faults in 3D modeling and applying the Boolean operation, we investigated the characteristic of faults at the intersectant part. An example of its application in hydropower engineering project was proposed. Its results show that this modeling approach can increase the computing efficiency while less computer memory is required, and it can also factually and objectively reproduce the CFN in the engineering region, which establishes a theoretical basis for 3D modeling and analysis of complex engineering geology. 相似文献
217.
刘利群 《甘肃联合大学学报(自然科学版)》2007,21(3):12-15
设G是顶点集合为V(G)={v0i|i=1,2,…,p}的简单图,n是正整数,称Mn(G)为G上的锥(或广义Mycielski图),如果V(Mn(G))={v01,v02,…,v0p;v11,v12,…,v1p;…,vn1,vn2,…,vnp,w},E(Mn(G))=E(G)∪{vijv(i 1)k|v0jv0k∈E(G),1≤j,k≤p,i=0,1,…,n-1}∪{vnjw|1≤j≤p}.在这篇文章里,我们讨论了星和扇上的锥的D(2)-点可区别的正常边染色,并给出了相应色数. 相似文献
218.
基于A*算法的远程导弹三维航迹规划算法 总被引:2,自引:0,他引:2
提出了一种基于A*算法的三维航迹规划方法.该方法将远程导弹的运动学模型离散化,利用导弹过载作为控制量,并结合约束条件,直接对三维空间进行最优航迹搜索.航迹规划过程不仅结合了导弹的本身机动特性,并且充分利用地形信息进行地形回避和威胁回避.仿真实验表明,该方法能够直接规划出三维空间中满足导弹过载约束的最优航迹. 相似文献
219.
SHI Feng LI Nana NIU Xiaohui 《武汉大学学报:自然科学英文版》2007,12(2):235-238
3-dimension HPNX offiattice model is developed from the 2-dimension HP offiattice model. In the HP model, 20 types of amino acid monomers are divided into two classes, H (non-polar monomer) and P (polar monomer). In the HPNX model, polar monomers are split into positively charged (P), negatively charged (N) and neutral (X) monomers. A new evolutionary algorithm is applied to study long chains of the HPNX offiattice protein model. This method successfully predict the structures of several proteins in the 3-dimension space that are similar to the structures gotten by X-Ray Crystallography and NMR and published in the PDB(Protein Data Bank). 相似文献
220.
广义系统具有完整性圆盘极点配置控制器设计 总被引:1,自引:2,他引:1
考虑线性连续广义系统具有完整性的圆盘极点配置设计问题·利用广义李亚普诺夫方程和不等式给出系统正则、无脉冲,以及极点在圆盘内的充分必要条件·同时针对执行器失效的线性连续广义系统,利用Riccati不等式给出具有执行器完整性圆盘极点配置控制器的设计方法,所设计的状态反馈控制器在系统正常时是正则、无脉冲、极点配置在圆盘内即系统是D允许的,在一定条件下,仍能使执行器故障具有D允许性 相似文献