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多波束测深系统的精度评估方法研究 总被引:2,自引:1,他引:2
在分析了多波束测深系统测量误差来源的基础上,讨论了多波柬测深系统静态精度、相对精度和绝对精度的系统精度评估方法。采用的静态精度评估方法就是在多波柬测深系统静止的条件下考核其对同一位置测量深度的误差;相对精度评估方法就是布设多条交叉重叠的测线,考核交叉重叠点的测深误差;绝对精度评估方法是在多波束测深的同时利用高精度的测深仪测量同一区域,用此参考地理模型来检验多波束测深的精度。根据误差理论,三种精度评估的方法分别从系统稳定性、自符合性和系统误差方面确定各误差源的综合误差,它们是检验多波束测深系统精度是否符合海道测量标准的有效方法。文中给出了系统试验数据的重要结果及设备验收的方法。 相似文献
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为解决单波束测深系统利用单一延迟值改正往返断面位移精度低的问题,在分析单波束测深系统误差产生原理基础上,得出往返断面位移是由系统延迟引起的固定差和换能器偏角引起的与深度相关比例误差共同作用的结果,通过建立水深与往返断面位移之间的数学模型,证实水深与断面位移具有极高相关性。利用求取单波束系统延迟及换能器偏角参数,对同一测深系统各断面形态断面进行位移改正,断面往返测数据具有良好的吻合性。证实顾及水深的单波束系统往返断面位移改正方法具有良好的系统适用性,能提高测深精度。 相似文献
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《海洋测绘》2003,(6)
海洋测量机载激光测深中的深度归算技术欧阳永忠 ,黄谟涛 ,翟国君 ,等 (1— 1)多波束测深系统的归位问题研究赵建虎 ,刘经南 (1— 6 )海图深度基准面的算法研究暴景阳 ,黄辰虎 ,刘雁春 ,等 (1— 8)海洋测线网平差中拟稳测线系统误差的影响李明叁 ,刘雁春 ,黄谟涛 ,等 (1— 13)侧扫声纳和多波束测深系统在海洋调查中的综合应用罗深荣 (1— 2 2 )侧扫声纳数据库管理设计滕惠忠 ,邓雪清 ,郭思海 (1— 2 7)多波束测深系统的安装校准王闰成 (1— 34)双频测深仪在海底浅层物质分类中的应用郭发滨 ,刘忠臣 (1— 4 6 )黄河改道后河口至黄河海港海岸… 相似文献
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海洋测深中时移和偏移效应综合分析与改正 总被引:2,自引:2,他引:2
海洋测深中,定位与测深分属两个独立的技术系统,测深时两系统在时间和空间上难以保持一致,从而存在匹配误差。本文着重论证了产生匹配误差的两种因素(延时效应和定位中心与测深中心的偏移效应)之间的关系及其对测深结果的综合影响,最后给出了各种情况下匹配误差的改正方法。数值实验结果表明该算法的有效性。 相似文献
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多波束测量过程中,受到多种因素的影响,不可避免地存在各种误差,其中系统某个部件出现故障也不少见,如换能器、行波管、大功率微波开关或表层声速仪等器件功能不正常,引起多波束每 ping (一个发射接收周期) 数据中部分固定波束号的测深结果发生系统性偏移,以 2003 年东海调查 SeaBat900X 数据为例,其在垂直航向正投影平面上出现类似“W”字型的系统误差。本文基于该批次数据,系统分析了该类型系统偏差成因及外观表现,针对性提出基于等均值-方差拟合模型的改正方法,首先对异常区域和正常区域分别拟合地形趋势线,统计其均值和方差;然后以正常区域为基准,对异常区域内数据进行压缩和移动;最后通过面积差法,对数据中存在的折射残差进行消除,从而有效去除“W”型残差。文中实测数据验证了本文算法的有效性和可行性,对多波束其他类型的测深系统偏差处理具有一定的参考意义。 相似文献
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AUV 等无人装备研制过程中如何选择合适的多波束测深系统以满足特定作业场景需求是工程技术人员关心的问题之一。从多波束测深声呐系统与 AUV 等无人系统的匹配角度出发,采用混响背景下的主动声呐方程建立了不同工作频率多波束作用距离计算评估方法,对 100 kHz~500 kHz 的多波束测深声呐作用距离进行了计算对比。在此基础上,采用线性调频、FFT 波束形成、脉冲压缩、样条插值扩充目标角度、Rife 算法优化角度估计技术,建立了多波束测深声呐的成像仿真方法,并通过直线地形、台阶地形对多波束测深声呐的成像特点和测深分辨率进行了分析。主要结论:1)建立了一种多波束作用距离评估的方法,可用于指导无人装备用多波束测深声呐频率参数的选型;2)建立的多波束测深声呐仿真办法可以帮助工程技术人员更直观地理解多波束测深声呐的成像特点;3)通过仿真分析了 CW 信号与线性调频信号下的距离分辨率,可用于指导波束测深作业时的高度、信号参数设置。 相似文献
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在海洋磁力测量中,因受测量环境及各项改正的残余量等因素的系统性影响,不同测线间存在着不同程度的系统差,这种测线系统差会使测区磁场水平不统一,导致磁异常等值线图失真。为此,研究了基于虚拟检查线的海洋地磁测量数据调差方法,该方法尝试在不使用检查线数据情况下,沿垂直于测线方向选取一定数量的虚拟检查线,根据测线数据拟合出各条虚拟检查线上场的分布规律,并将测线方向拟合前后残差的平均值作为各条测线上的测线系统差,对各条测线数据进行改正。仿真计算与分析表明:对于磁异常变化较平缓的测区,该方法可以有效消除测线系统差;当磁异常变化剧烈时,该方法可以部分消除测线系统差。 相似文献
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Dhouha Ferjani Slim Gana 《Deep Sea Research Part I: Oceanographic Research Papers》2010,57(10):1177-1191
Seasonal hydrographic conductivity–temperature–depth surveys and moored current meter measurements have been analysed using an inverse approach in order to highlight the main features of the circulation in the western Sicily Strait during 2003. The variational inverse section model combines different types of constraints to seek for a continuous flow field satisfying data and physical assumptions within prescribed prior error bars. It is based on a finite element discretization that allows an appropriate resolution of very irregular topography. The corresponding results, consistent with data and dynamics, are providing new insight into the circulation of the surface and intermediate layers in conjunction with transport and formal error estimates during five hydrographic cruises. In the upper layer, these insights include the southward Atlantic Tunisian Current (ATC) off the Cap Bon Coasts, its high variability at short time-scales and its recirculation during October. For the Levantine Intermediate Water (LIW) regime, a detailed view of the circulation in the western Sicily Strait is given evidencing its recirculation at the western sill during the same period. Transports for both ATC and LIW are computed and found to be maximum in spring and decrease in summer and fall. 相似文献
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为了对海道测量中测线定位精度进行评估,以及为补偿测线系统误差的需要,提出了实测定位折线模型,同时在利用小波降噪算法求得拟合航迹线的基础上,提出了拟合定位测线的概念,针对测线的不同形态给出了拟合测线的另外两种模型,即拟合直线和拟合折线。仿真实验表明:提出的三种测线模型均满足1:2 000以下比例尺测图要求;在满足定位精度和测线正横水深梯度不超限的约束条件下,可以用拟合测线代替原始测线进行数据的后处理;三种测线模型对系统误差不存在"淹没效应";拟合折线可以方便地减弱测线内受方向、船速等系统误差的影响。 相似文献
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Optimal interpolation method is applied to Geosat altimetry data both to remove orbit error and to separate temporal mean sea surface dynamic topography (SSDT) from temporal fluctuations around the mean. Loss of long-wavelength oceanic signals at orbit error reduction procedure is smaller in this method than that in conventional collinear methods, but the areal average height over the study domain is still removed as the orbit error. The fluctuation SSDT is quantitatively evaluated by sea level data from tide gauge stations at Japanese islands. The correlation coefficient of the two sea-level variations is 0.83 when the loss of the areal average is compensated by the seasonal variation of the areal average height determined from the climatological monthly-mean SSDT. In addition, the improvement of the geoid model by combined use of Seasat altimetry data and hydrographic data is validated through the estimated temporal mean SSDT. In a local area where hydrographic data contemporary with the Seasat mission exist, the geoid model has been significantly improved so that the absolute SSDT can be determined from combination of the altimetry data and geoid model; the absolute SSDT describes the onset event of a quasi-stationary large meander of the Kuroshio south of Japan very well. Outside this local area, however, errors of several tens of centimeters still remain in the improved geoid model. 相似文献
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《Deep Sea Research Part I: Oceanographic Research Papers》2001,48(6):1347-1373
The quantification of vertical motion and vertical fluxes is essential in our ability to predict and tolerate climate change. However, diagnostic estimations might be affected by the errors arising from the necessary compromise between spatio-temporal resolution and cost of hydrographic surveys. Observations of a numerical ocean model have been made in order to test the accuracy of different sampling strategies and their possible a-posteriori corrections. A simple first-order correction method, computing a pseudo-synoptic data set from a non-synoptic data set and involving a geostrophic relocation of the stations is shown to correct significantly the synopticity error in hydrographic data, derived QG vertical motion and vertical temperature fluxes. Sensitivity analyses also show that the lack of synopticity is more critical than other factors, including the sampling resolution, the level of no-motion and the analysis. 相似文献