基于分布式控制力矩陀螺的水下航行器轨迹跟踪控制   总被引：2，自引：0，他引：2  

黄道敏  徐瑞昆  唐国元  冯雷  刘智  徐国华 《海洋工程》2018,36(6):69-76

基于控制力矩陀螺群(CMGs)的水下航行器具有低速或零速机动的能力。采用基于分布式CMGs的水下航行器方案,并研究其水平面的轨迹跟踪控制问题。通过全局微分同胚变换将非完全对称的动力学模型解耦成标准欠驱动控制模型,并根据简化的模型构建其轨迹跟踪的误差动力学模型,将轨迹跟踪控制问题转化为误差模型镇定问题。基于一种分流神经元模型和反步法设计了系统的轨迹跟踪控制律,该控制器不需要对任何虚拟控制输入进行求导计算,且能确保跟踪误差的最终一致有界性。仿真结果表明该控制器能够实现在不依赖动力学参数先验知识的情况下对光滑轨迹的有效跟踪。  相似文献   

国产高分辨率遥感影像农村公路核查方法及其应用     

蔡红玥  袁胜古  阳柯  王芳  盛光晓 《测绘通报》2020,(3):91-95

传统的农村公路核查需要人工实地抽查或通过GNSS设备进行信息采集验核，存在成本高、效率低等问题。遥感影像具有成像范围广、时效性高、成本低、能客观反映现实情况等优点。相比于传统方法，将遥感影像引入农村公路核查，能客观、准确、高效地对农村公路相关信息进行核查。本文基于国产高分辨率遥感影像，结合农村公路遥感核查业务，采用遥感影像道路提取算法，设计并实现了一种农村公路核查方法。将本方法应用于某中部省份农村公路遥感核查业务，实际应用表明该方法能有效提高现有农村公路遥感核查的工作效率。  相似文献   

High-pressure eclogites in northern Jiangsu – southern Shandong province, eastern China     

MASAKI ENAMI  QUIJA ZANG  YUJUN YIN 《Journal of Metamorphic Geology》1993,11(4):589-603

Abstract Eclogites are distributed for more than 500 km along a major tectonic boundary between the Sino-Korean and Yangtze cratons in central and eastern China. These eclogites usually have high-P assemblages including omphacite + kyanite and/or coesite (or its pseudomorph), and form a high-P eclogite terrane. They occur as isolated lenses or blocks 10 cm to 300 m long in gneisses (Type I), serpentinized garnet peridotites (Type II) and marbles (Type III). Type I eclogites were formed by prograde metamorphism, and their primary metamorphic mineral assemblage consists mainly of garnet [pyrope (Prp) = 15–40 mol%], omphacite [jadeite (Jd) = 34–64 mol%], pargasitic amphibole, kyanite, phengitic muscovite, zoisite, an SiO₂ phase, apatite, rutile and zircon. Type II eclogites characteristically contain no SiO₂ phase, and are divided into prograde eclogites and mantle-derived eclogites. The prograde eclogites of Type II are petrographically similar to Type I eclogites. The mantle-derived eclogites have high MgO/(FeO + Fe₂O₃) and Cr₂O₃ compositions in bulk rock and minerals, and consist mainly of pyrope-rich garnet (Prp = 48–60 mol%), sodic augite (Jd = 10–27 mol%) and rutile. Type III eclogites have an unusual mineral assemblage of grossular-rich (Grs = 57 mol%) garnet + omphacite (Jd = 30–34 mol%) + pargasite + rutile. Pargasitic and taramitic amphiboles, calcic plagioclase (An₆₈), epidote, zoisite, K-feldspar and paragonite occur as inclusions in garnet and omphacite in the prograde eclogites. This suggests that the prograde eclogites were formed by recrystallization of epidote amphibolite and/or amphibolite facies rocks with near-isothermal compression reflecting crustal thickening during continent–continent collision of late Proterozoic age. Equilibrium conditions of the prograde eclogites range from P > 26 kbar and T= 500–750°C in the western part to P > 28 kbar and T= 810–880°C in the eastern part of the high-P eclogite terrane. The prograde eclogites in the eastern part are considered to have been derived from a deeper position than those in the western part. Subsequent reactions, manifested by (1) narrow rims of sodic plagioclase or paragonite on kyanite and (2) symplectites between omphacite and quartz are interpreted as an effect of near-isothermal decompression during the retrograde stage. The conditions at which symplectites re-equilibrated tend to increase from west (P < 10 kbar and T < 580°C) to east (P > 9 kbar and T > 680°C). Equilibrium temperatures of Type II mantle-derived eclogites and Type III eclogite are 730–750°C and 680°C, respectively.  相似文献   

单片机在卫星天线控制系统中的应用     

樊昌元  邓洪 《成都信息工程学院学报》2005,20(1):41-44

主要介绍卫星天线控制系统中天线旋转定位控制的软硬件设计和实现。该部分的主要功能是：接收红外遥控器的信号；检测前面板上的按键信号；检测传感器反馈的信号；根据所得信号作出相应的动作。  相似文献   

Combined mine tremors source location and error evaluation in the Lubin Copper Mine (Poland)     

Andrzej Leniak  Grzegorz Pszczo&#x;a 《Tectonophysics》2008,456(1-2):16

A modified method of mine tremors location used in Lubin Copper Mine is presented in the paper. In mines where an intensive exploration is carried out a high accuracy source location technique is usually required. The effect of the flatness of the geophones array, complex geological structure of the rock mass and intense exploitation make the location results ambiguous in such mines. In the present paper an effective method of source location and location's error evaluations are presented, combining data from two different arrays of geophones. The first consists of uniaxial geophones spaced in the whole mine area. The second is installed in one of the mining panels and consists of triaxial geophones. The usage of the data obtained from triaxial geophones allows to increase the hypocenter vertical coordinate precision. The presented two-step location procedure combines standard location methods: P-waves directions and P-waves arrival times. Using computer simulations the efficiency of the created algorithm was tested. The designed algorithm is fully non-linear and was tested on the multilayered rock mass model of the Lubin Copper Mine, showing a computational better efficiency than the traditional P-wave arrival times location algorithm. In this paper we present the complete procedure that effectively solves the non-linear location problems, i.e. the mine tremor location and measurement of the error propagation.  相似文献   

平均大潮高潮面的科学定位和现实描述   总被引：4，自引：0，他引：4  

许家琨  刘雁春  许希启  翟国君  林有财  暴景阳  黄辰虎 《海洋测绘》2007,27(6):19-24

在对平均大潮高潮面进行科学定位的基础上,进一步阐明了我国海岸线(岛屿岸线、明礁、灯塔)起算面的定义。引入了三个国标的定义和沿海五省制定的法律条例的规定,结合东海及其岛屿海岸线不同起算面的计算算例,论证了我国海岸线就是平均大潮高潮面形成的实际痕迹线,并以此作为海陆分界线的科学定位和现实意义,澄清了在这一领域存在的一些异议和模糊认识。同时,并就这一重要的基准面进行现实的描述,以期服务于当前我国沿海经济建设、海域使用管理、海岸带开发和有关专项调查以及海洋测绘事业中。  相似文献   

亚像素定位的关键问题研究   总被引：1，自引：0，他引：1  

王成亮  邹峥嵘  闾海庆  王静 《海洋测绘》2007,27(1):70-73

分析了控制点标志的选择与设计,采用了图像处理、Hough变换、角点与直线高精度定位算子等方法,实现了中南大学近景摄影测量二维控制场1 350个人工标志点的自动识别和亚像素定位,仿真图检测平均精度达到±0.05像素。  相似文献   

中国海区区域地质编图中重磁图的编制方法     

张训华 《海洋地质与第四纪地质》1994,14(4):95-100

本文简要介绍了局控项目《中国海区１∶５０万区域地质编图（大连幅）》重力异常图、磁力异常图的编制过程，给出了一种以计算机为手段、实现编图自动化的新方法，并分析了该方法与以往编图方法的不同和优点，以国际分幅在中国海区开展区域地质编图尚属首次，在既无海区地质调查规范，又无海区地质调查编图规范的情况下，这一工作无异具有开创性。从理论上系统总结出一套切实可行的编图方法，对于编制中国海区区域地质调查编图规范以  相似文献   

造山带大陆斜坡沉积类型     

蔡雄飞  蔡海磊  刘德民  陈斌 《海洋地质前沿》2006,22(1):9-13

造山带大陆斜坡可以划分出有扇与无扇大陆斜坡两种沉积类型。有扇大陆斜坡以近源浊积岩、碎屑流为特色;无扇大陆斜坡以远源浊积岩、等深岩、半远洋沉积为特色。因而大陆斜坡也是一个多种沉积作用活跃的场所。造山带深水沉积绝不是常人认为是单一的复理石、千篇一律的重力流,而是内容十分丰富的沉积作用非常活跃和堆积的场所。  相似文献   

近1300年来古胶州港位置的变迁   总被引：4，自引：0，他引：4  

于世永  卢春成 《海洋湖沼通报》1995,(4):16-20

本文主要依据有关方志、文史资料，着重考证了近１３００年来古胶州港位置的变迁，研究发现，古胶州港的位置自唐代至清末近１３００年间，沿胶州湾西、北岸大致经历了７次变更，特别自明代开始，港口位置变迁尤为频繁，作者初步分析认为这与历史时期胶州湾内西、北岸的不断淤涨和胶莱南河、大沽河口的冲淤作用有关。  相似文献