无限终端线性二次调节器最优输出反馈律     

张雷  曾蓉 《成都理工学院学报》2007,34(6):653-656

线性二次调节器问题在现代控制理论中占有重要地位。该文针对状态调节器最优反馈律结构复杂、不便工程实现等问题，着重讨论了无限终端带有输出方程的状态调节器的最优输出反馈律，还跟踪讨论了无限终端输出调节器的最优反馈律。所得结论可降低调节器的复杂程度，便于工程实现。  相似文献   

新疆层控型铅锌矿   总被引：3，自引：2，他引：3  

董连慧  庄道泽  冯京  张良臣 《新疆地质》2007,25(4):339-344

简要叙述了新疆周边国家及地区层控型铅锌矿的时空分布规律及重要成矿带的特点,并以此为背景分别对新疆层控铅锌矿进行了系统分析研究,总结了新疆主要层控铅锌矿床的时空分布规律、构造环境、层位、断裂等控矿规律,提出并论述了新疆新确定的阿尔泰等8条重要层控型铅锌成矿带和诺尔特等14条矿带特征,指出新疆今后寻找沉积岩容矿的层控铅锌矿主要方向是以塔里木(含柴达木)周边前寒武纪基底地块和不同时代陆缘盆地为主,而寻找火山-沉积岩容矿的层控铅锌矿则是以准噶尔周边和西伯利亚板块南部边缘的大陆边缘裂陷盆地、裂陷槽、上叠盆地为主等.  相似文献   

执法为民依法治"震"     

陈俊晖  陈晓发 《国际地震动态》2007,(10):32-35

通过对防震减灾法在实施过程中存在不善于执法和执法不严等问题的分析,提出加强地震行政执法,依法保护全社会各行各业建设工程必须达到抗震设防要求,保证防震减灾工作有序地进行,切实收到减灾成效。笔者拟从端正执法思想,规范执法行为,强化执法监督三方面综述加强地震行政执法力度对防震减灾、造福民众的重要意义。  相似文献   

月球重力场的确定及构建我国自主月球重力场模型的方案研究   总被引：3，自引：0，他引：3  

李斐  鄢建国 《武汉大学学报(信息科学版)》2007,32(1):6-10

对绕月卫星的运动规律以动力学方程的形式进行了描述，并讨论了绕月卫星定轨中动力法和几何法的适用性以及通过定轨观测获取月球重力场模型的计算方式和优化算法’在归纳月球重力场确定的技术流程的基础上。针对月球背面绕月卫星摄动无法观测的困难，分析了目前所能采取的各种处理办法及其特征。结合我国即将发射的“嫦娥卫星”装备有激光测高计这一特点，提出将月球表面地形与月球重力场之间的强相关性作为约束来确定我国自主重力场模型的设想。  相似文献   

Source parameters and stress release of seismic sequences occurred in the Friuli-Venezia Giulia region (Northeastern Italy) and in Western Slovenia     

Gianni Bressan  Stefano Kravanja  Gianlorenzo Franceschina   《Physics of the Earth and Planetary Interiors》2007,160(3-4):192-214

The source parameters of the major events of a swarm and of two seismic sequences, occurred in the Friuli area (Northeastern Italy) and in Western Slovenia, were estimated. The Claut swarm (C96) occurred since the end of January to June 1996, with a M_D 4.3 major shock and it appears composed of three sub-sequences. The two sequences are the Kobarid sequence (K98) started on April 12, 1998 with a M_D 5.6 mainshock and the M.te Sernio (S02) sequence caused by the February 14, 2002 earthquake (M_D = 4.9). Acceleration and velocity data recorded by the local seismic network of the Istituto Nazionale di Oceanografia e di Geofisica Sperimenale (OGS) and corrected for attenuation, were employed to estimate seismic moments and radiated energies. Source dimensions were inferred from the computed corner frequencies and the stress release was estimated from the Brune stress drop, the apparent stress and the RMS stress drop. On the whole, seismic moments range from 1.7 × 10¹² to 1.1 × 10¹⁷ N m, and radiated energies are in the range 10⁶–10¹³ J. Brune stress drops are scattered and do not show any evidence of a self-similarity breakdown for sources down to 130 m radius. The radiated seismic energy scales as a function of seismic moment, with a slope of the scaling relation that decreases for increasing seismic moments.The mechanism of stress release was analyzed by computing the ɛ parameter of Zuniga [Zuniga, R., 1993. Frictional overshoot and partial stress drop. Which one? Bull. Seismol. Soc. Am. 83, 939–944]. The K98 and S02 sequences are characterized by a wide range of the ɛ parameter with stress drop mechanism varying from partial locking to overshoot cases. The ɛ values of the C96 swarm are more homogeneous and close to the Orowan's condition. The radiated seismic energy and the ratio of stress drop between mainshock and aftershocks appear different among the analyzed cases. We therefore investigated the relationship between the stress parameters of the main shock and the energy radiated by the aftershock sequences. For this purpose, we also estimated the source parameters of two other sequences occurred in the area, with mainshocks of M_D 4.1 and 5.1, respectively. We found a positive correlation between the Brune stress drop of the mainshock and the ratio between the radiated energy of the mainshock and the summation of the energies radiated by the aftershocks.  相似文献   

Modeling permeability in imperfectly layered porous media. I. Derivation of block-scale permeability tensor for thin grid-blocks     

W. Zijl  J. M. T. Stam 《Mathematical Geology》1992,24(8):865-883

Practical expressions are given for the nine components of the block-scale permeability tensor of a thin block. These expressions are derived from the local-scale continuity equation and Darcy's law in an anisotropic layered porous medium. The flow problem is separated in a bottom-flux problem and a top-flux problem, both of which can be solved in essentially the same way. The bottom-flux problem has been worked out in detail, and has been separated in two parts: a vertical potential difference and a horizontal potential difference part. Each is solved with a different approach specially designed for it. Depth-averaged expressions are obtained first, after which block-scale expressions are obtained by assuming a constant depth-averaged flux. In the zeroth order, this results in the well-known Dupuit approximation in geohydrology, and the vertical equilibrium (VE) approximation in petroleum reservoir engineering. The novelty of the theory presented here stems from the application of a perturbation technique to obtain first-order corrections to these well-known results. The local-scale laws are applied in the coordinate system coinciding with the principal axes of the local-scale permeability tensor. Only in this coordinate system the local-scale permeability tensor has zero off-diagonal components. However, since the porous medium is imperfectly layered, the first-order corrections show that the off-diagonal components of the block-scale permeability tensor are not zero. Furthermore, the block-scale permeability tensor is generally nonsymmetric, which implies that a coordinate system in which the off-diagonal terms disappear does not exist.  相似文献   

On Integral Measures Of The Neutral Barotropic Planetary Boundary Layer     

S. S. Zilitinkevich  I. N. Esau 《Boundary-Layer Meteorology》2002,104(3):371-379

Two types of neutral planetary boundary layer (PBL) are distinguished:truly neutral – developed against a neutrally stratified free flow, and conventionally neutral – developed against a background stable stratification. Atmospheric PBLs treated asneutral are almost always conventionally neutral. Theoretical reasoning and results from large-eddy simulation (LES) show that A and B coefficients of the Rossby-number similarity theory are not constants. The same is true for thecoefficient C_h in the Rossby–Montgomery formula for the neutral boundary-layer depth h = C_hu*/|f|, where u_* is the friction velocity. Contrary to classical ideas, A, B and C_h depend on the ratio _N N/|f| of the free-flow Brunt–V*auml;isäl ä frequency N to the absolute value of the Coriolis parameter |f|. This new development can explain why atmospheric and LES estimates of A, B and C_h appear inconsistent. It results from neglecting the fact that atmospheric data for _N 10² were compared with LES data for _N = 0, violating an obvious requirement of similarity with respect to _N.  相似文献   

Reality of the relation between geological objects and mathematical models     

M. áek  Z. Kivánek 《Mathematical Geology》1991,23(1):41-46

Mathematical models and their targets are considered. The results provide an explanation why the shape of the density distribution function is dependent upon both size of the geological object and number of observations. These results have importance both for preparative and interpretative phases of prospecting.  相似文献   

地矿法制建设的重要成果——祝贺《广西壮族自治区矿产资源管理条例》的颁布施行     

陈维田 《南方国土资源》2001,(1)

文章论述了《广西壮族自治区矿产资源管理条例》是与新的《中华人民共和国矿产资源法》相配套的地方性法规 ,前者是贯彻落实后者的具体主要措施 ,必须认真学习 ,广泛宣传 ,贯彻执行 ,确保矿业经济健康发展  相似文献   

加入WTO对成都法律专业人才的影响与对策     

曹向兰  郭谊  熊文枫 《成都信息工程学院学报》2005,20(4):496-498

加入WTO,使我国法律服务市场范围扩大,各级法院、检察院受理的案件数量上升,这急需一大批高素质的法律专业人才.目前成都法律专业人员的数量质量,均不能满足这种需要.为此,可通过加强现有高校法学专业建设,对在职人员进行培训、进修,严把司法考试关,大力发展JM教育,选派优秀人才到国外考察、学习等措施来加快成都高素质法律专业人才的培养.  相似文献