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基于AIS信息校准的双频地波雷达的船只融合跟踪 总被引：2，自引：0，他引：2
高频地波雷达（HFSWR）和自动船只确认系统（AIS）是船只跟踪的重要传感器。高频地波雷达可以用来跟踪探测区域的所有船只,而AIS只能用来确认合作船只的信息。由于海杂波的干扰,使用单频率地波雷达的船只跟踪会淹没在布拉格峰值的盲区里,改变探测频率是克服这一缺点的有效手段。在这种背景下,我们提出一种基于AIS校准的双频雷达融合探测算法。因为不同频率的地波雷达测量与AIS的测量值存在系统误差,所以AIS信息可以用来估计和校准地波雷达的每个频率的系统误差。首先,将合作目标的点迹测量与地波雷达的点迹测量通过JVC分配算法进行点迹关联。从合作船只的点迹关联结果中,双频雷达的系统误差可以估计和校准。其次,基于校准的双频雷达数据,使用融合JPDA-UKF算法进行船只跟踪。通过真实探测的数据的实验结果显示所提算法可以实时跟踪船只,相比单频率跟踪可以进一步提高跟踪能力和跟踪精度。 相似文献
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Due to high density of vessel traffic, busy waterways are water areas with high potential for collisions. The application of AIS makes it possible to investigate accurate and actual behavior of collision-involved ships, and benefits vessel traffic management and waterways design for these areas. As a case study, the authors focus on a Traffic Separation Scheme (TSS) off Rotterdam Port in Europe, and using AIS data, statistical analysis is made for collision involved ships. In order to identify the correlation of CPA, which is a key indicator for collision avoidance, with ship's size, speed, and course, linear regression models are developed. To assess risks, a dynamic method based on SAMSON is presented. 相似文献
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船只目标SAR、HFSWR和AIS多手段融合探测的点迹关联分析 总被引：3，自引：1，他引：2
A space-borne synthetic aperture radar （SAR）, a high frequency surface wave radar （HFSWR）, and a ship automatic identification system （AIS） are the main remote sensors for vessel monitoring in a wide range. These three sensors have their own advantages and weaknesses, and they can complement each other in some situations. So it would improve the capability of vessel target detection to use multiple sensors including SAR, HFSWR, and A/S to identify non-cooperative vessel targets from the fusion results. During the fusion process of multiple sensors＇ detection results, point association is one of the key steps, and it can affect the accuracy of the data fusion and the efficiency of a non-cooperative target＇s recognition. This study investigated the point association analyses of vessel target detection under different conditions： space- borne SAR paired with AIS, as well as HFSWR, paired with AIS, and the characteristics of the SAR and the HFSWR and their capability of vessel target detection. Then a point association method of multiple sensors was proposed. Finally, the thresholds selection of key parameters in the points association （including range threshold, radial velocity threshold, and azimuth threshold） were investigated, and their influences on final association results were analyzed. 相似文献
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随着全球经济的快速发展,海上运输由于其运力大、运费低而变得更具实用性。然而,这也意味着在海上航道行驶的船只正变得越来越多,这将导致在复杂的海洋环境中航海船只发生事故的可能性会很高。据相关历史的统计,在海域中航行缺乏高精度导航数据会导致大量事故,这种累积的事故信息可以被用来提高航海的安全性。本文通过将蕴含在AIS (Automatic Identification System) 大数据中的经验导航信息挖掘出来,以辅助实现复杂海事环境下安全可靠的船舶路径的生成。本文提出了一种基于大数据自动生成船舶路径的新方法。该方法首先在大量船舶轨迹上通过DBSCAN (Density-Based Spatial Clustering of Applications with Noise) 聚类形成不同的轨迹矢量簇。然后,迭代计算轨迹矢量簇的中心线,并从这些中心线之间的节点-弧段拓扑关系来构建航道网络。最后,基于航道网络来实现船舶路径的生成,对于航道网络未覆盖的海域,则通过海洋环境风险栅格的路径规划来实现船舶路径的生成。不同海域不同AIS数据集进行的多次实验结果表明,本文提出的船舶路径生成方法是有效性。 相似文献
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针对现有的轨迹相似度匹配算法用于渔船AIS (Automatic Identification System)与ARPA (Automatic Radar Plotting Aid)轨迹匹配时存在复杂度高、效率低等问题,本文提出基于时空约束和三角形迭代划分的渔船AIS与ARPA轨迹匹配算法TSC-TIP (Temporal and Spatial Constraint-Triangle Iterative Partitioning)。首先采用时空约束法筛选出ARPA目标时空约束范围内的AIS数据;其次采用三角形相似算法选择与AIS数据具有相似特征点的APRA轨迹数据;最后设计了子轨迹迭代划分法将每条轨迹划分为两条子轨迹并采用三角形相似法对子轨迹进行迭代筛选。为验证算法的性能,用渔船的真实AIS轨迹数据和ARPA轨迹数据进行了试验,结果表明：与基于经典距离的相似性度量方法相比,提出的TSC-TIP算法在不影响匹配准确率的前提下,匹配时间减少了95%。研究表明：TSC-TIP算法能有效匹配渔船AIS与ARPA轨迹数据,为面向AIS与ARPA的渔船轨迹数据融合研究提供了新思路。 相似文献
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文章针对海洋渔业由于过度捕捞造成渔业资源枯竭的问题,提出了一种基于海洋遥感(ORS)、全球定位系统(GPS)和海洋地理信息系统(MGIS)等高新技术的海洋捕捞与海水养殖监管系统设计方案,可以远程自动对海洋渔业区域的水质多参数信息和养殖环境视频信息进行综合采集、传输及监控,也可以自动采集传输渔船RFID身份识别信息、渔船AIS自动识别信息、渔船GPS定位信息和捕捞生产视频信息等,并通过海洋精细渔业专家系统ES进行渔业养殖监控、渔业环境资源监测评估、渔船船数和功率数控制和海洋捕捞生产渔情监测等。该系统可以实现海洋渔业精细化捕捞和海洋渔业精细化养殖,促进海洋渔业可持续发展。 相似文献
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A study of the seakeeping performance of a set of fishing vessels is carried out aiming to identify the seakeeping criteria, and vessel conditions that limit the operability of the fishing vessels in certain sea states. Ship motions and derived responses are obtained in fully developed sea states using the transfer functions of the hull forms. Those responses are assessed against the prescribed values, for the chosen criteria, to determine the vessels operational conditions that might result in hazards or seasickness. For the purpose of this study, each fishing vessel is considered operating in sea states 5 and 6, with different Froude numbers and heading angles, and their short term responses are assessed against the most relevant criteria related with the absolute and relative motions, accelerations, slamming and green water on deck. The results obtained show that roll and pitch criteria are most critical for seakeeping performance, and there is a significant influence of the transverse metacentric height, GMt, and the location of the reference checking points in the seakeeping performance of these fishing vessels. 相似文献
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为了从海量渔船轨迹数据中挖掘隐含的信息和知识,进而为渔业行政主管部门的决策提供科学依据,本研究以AIS渔船轨迹数据为研究对象,提出了一种基于深度学习和面向时空特征融合的海洋渔船密度预测方法：首先,利用渔船轨迹数据集对渔船行驶区域进行网格划分;其次,筛选出渔船高密度区域进行研究,避免数据稀疏性问题;再次,根据渔船轨迹数据的时空分析,构建三维时空融合矩阵;最后,通过卷积循环神经网络模型捕获渔船分布的时间和空间特征,并利用卷积神经网络的堆叠加强对空间特征的学习。实验通过东海海域渔船真实轨迹数据进行具体测试,结果表明渔船密度预测值与真实值非常接近,平均绝对误差为4×10-4,模型较好地拟合了渔船密度分布特征,有效地提高了渔船捕捞热点预测的准确性和鲁棒性。 相似文献
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Running attitudes of semi-displacement vessels are significantly changed at high speed and thus have an effect on resistance performance and stability of the vessel. There have been many theoretical approaches about the prediction of running attitudes of high-speed vessels in calm water. Most of them proposed theoretical formulations for the prismatic hard-chine planing hull. In this paper, running attitudes of a semi-displacement round bilge vessel are theoretically predicted and verified by high-speed model tests. Previous calculation methods for hard-chine planing vessels are extended to be applied to semi-displacement round bilge vessels. Force and moment components acting on the vessel are estimated in the present iteration program. Hydrodynamic forces are calculated by ‘added mass planing theory’, and near-transom correction function is modified to be suitable to a semi-displacement vessel. Next, ‘plate pressure distribution method’ is proposed as a new hydrodynamic force calculation method. Theoretical pressure model of the 2-dimensional flat plate is distributed on the instantaneous waterplane corresponding to the attitude of the vessel, and hydrodynamic force and moment are estimated by integration of those pressures. Calculations by two methods show good agreements with experimental results. 相似文献
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Method to Determine Depositional Range of Sediment Transported from Multiple Sources in Water Area 总被引：1，自引：0，他引：1
Ying Qiang Jing Fei Ma Jin Rong
Engineer Nanjing Hydraulic Research Institute Nanjing Lecturer Nanjing College of Navigation Engineering Nanjing Assistant Engineer Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1995,(3)
- The sediment from different sources have different content of the characteristic elements. According to the fuzzy mathematical theory, corresponding calculation and cluster analysis of each sediment sample are carried out, so the main courses of sediment transport in water area can be obtained. The characteristics of sediment from different sources are analysed. It is found that the sediment deposited of certain point in water area is due to the sources' contributions which can be calculated by the formula derived in this paper. Based on the distribution of the contribution values, the depositional range of sediment from each source can be determined. The depositional range in Huangmao Bay is determined as an example. 相似文献
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漫衰减系数是一个重要的海洋光学参数,能够为水体环境变化、水质分析以及水产养殖等方面提供基础性数据。针对目前船载实地测量效率与分辨率低、卫星遥感反演精度与分辨率较低的局限性,本文提出一种基于机载LiDAR测深水体波形的漫衰减系数提取方法。该方法首先通过分层异构模型的机载LiDAR波形分解算法得到水体散射回波,利用激光在水体中的衰减特性,构建漫衰减系数提取模型,最终获取大面积水域漫衰减系数的空间分布。采用西沙甘泉岛与江苏连云港两个航次的实测数据对所提算法进行了验证,本算法无需每个测深点的水底底部回波强度和深度即可反演得到漫衰减系数,并且在浑浊水域也可取得较好的效果,表明在中国近海利用机载LiDAR测深系统能够有效获取高精度的漫衰减系数。 相似文献
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The use of ship's radar for collision avoidance presents a fundamental problem in threat detection and identification since all vessel radar returns ("paints") look alike. As a result, when a ship master caught in a fog is trying to use his radio-telephone to work out a maneuvering plan with another vessel, it is difficult for him to identify which blip on the planar position indicator PPI is the source of the voice on the radio. One solution now receiving worldwide attention is to fit all vessels with active transponders. The marine radar interrogator-transponder (MRIT) is an advanced form of transponder which includes an integral interrogator and works in coordination with the ship radar to provide not only target identity and "clutter-free" target paints, but also maneuvering information and such data as target's course, speed, draft, safe or dangerous cargo, etc. Mounted on a fixed navigation aid, the transponder portion alone can also function as a racon (radar beacon). This paper describes the operational parameter and reviews the system bench tests and sea trials. 相似文献
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提出一种基于温度剖面相似系数的水系划分方法。基本思想是:将各温度剖面视为独立样本,各深度数据为样本变量,先基于划分区域水文特征选取合理数量的水系中心剖面,再利用各样本与各中心剖面相似系数大小进行聚类,得到各水系划分数据集合;利用几何平均求得各水系集合新的中心剖面,重复剖面相似系数聚类过程,直至中心剖面不再变化为止。最后利用国家海洋信息中心发布的中国近海CTD温、盐产品对该方法进行试验,并对聚类得到的各类温度剖面展开讨论。结果较好的反应出各区域温度剖面特征,综合体现出东海各区域温度大小、海流、水团和水深特性。 相似文献
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In order to predict the roll motion of a floating structure in irregular waves accurately, it is crucial to estimate the unknown damping coefficients and restoring moment coefficients in the nonlinear roll motion equation. In this paper, a parameter identification method based on a combination of random decrement technique and support vector regression (SVR) is proposed to identify the coefficients in the roll motion equation of a floating structure by using the measured roll response in irregular waves. Case studies based on the simulation data and model test data respectively are designed to validate the applicability and validity of the identification method. Firstly, the roll motion of a vessel is simulated by using the known coefficients from literature, and the simulated data are used to identify the coefficients in the roll motion equation. The identified coefficients are compared with the known values to validate the applicability of the identification method. Then the roll motion is predicted by using the identified coefficients. The prediction results are compared with the simulated data, and good agreement is achieved. Secondly, the model test data of a FPSO are used to identify the coefficients in the roll motion equation. Then the random decrement signature of the roll motion is predicted by using the identified coefficients and compared with that obtained from the model test data, and satisfactory agreement is achieved. From this study, it is shown that the identification method can be effectively applied to identify the coefficients in the nonlinear roll motion equation in irregular waves. 相似文献