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基于测速测距激光雷达的飞行器地形匹配导航方法

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中国惯性技术学报 2024年第1期32卷 8-15页

作者：桑洋纪新春魏东岩尤逸轩张文超袁洪中国科学院空天信息创新研究院北京100094 中国科学院大学电子电气与通信工程学院北京100049 西北工业大学电子信息学院西安710129

针对中低空飞行器地形匹配与惯导组合中惯导误差累积导致高程图变形限制地形匹配精度、二维地形匹配运算量大和地形匹配失效时定位可用性差的问题,提出一种基于测速测距激光雷达的地形匹配导航方法。利用激光测速信息辅助构建高程图,减... 详细信息

针对中低空飞行器地形匹配与惯导组合中惯导误差累积导致高程图变形限制地形匹配精度、二维地形匹配运算量大和地形匹配失效时定位可用性差的问题,提出一种基于测速测距激光雷达的地形匹配导航方法。利用激光测速信息辅助构建高程图,减小高程图变形从而提高匹配精度,同时降低匹配结果与惯导的相关性;设计集成尺度不变特征变换(SIFT)特征与分步核验的地形匹配算法,提高匹配的实时性;采用激光测速信息辅助校正惯导,提高地形匹配失效时定位的可用性。典型场景地形数据的测试结果表明,基于激光测速辅助构建的高程图较基于惯导构建的高程图的地形匹配定位精度提高了36.6%,所提的卡方初始化随机抽样一致性地形特征误匹配检测算法(TCI-RANSAC)相比于RANSAC算法缩短了55.6%的核验时间,且测速信息的引入将组合定位精度提高了65.9%,具备较高的工程应用价值。

关键词：飞行器测速测距激光雷达地形匹配导航组合导航高程图构建特征匹配核验

Effect of Continuous Nursing Intervention on Psychological State and Medication Compliance of Patients with Acute Myocardial Infarction after PCI

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Journal of Advances in Medicine Science 2018年第1期1卷 9-11页

作者： dongyan wei The First Hospital of Fangshan Beijing102400China

Objective:To explore the effect of continuous nursing intervention on psychological status and medication compliance of patients with acute myocardial infarction after PCI operation.Methods:from February 2013 to September 2016,102 patients with acute myocardial infarction treated by PCI were selected and divided into two groups,51 cases in each group according to the different nursing methods.The observation group was added continuous nursing on the basis of routine nursing,while the control group was the usual nursing mode.The mental state of the two groups before and after treatment was evaluated,and the patients were followed up for 6 months after discharge.The compliance of the two groups at 1,3 and June after discharge was statistically analyzed.Results:before nursing,there was no significant difference in the mental state evaluation between the two groups(P>0.05).After nursing,the mental status of the two groups was improved,while the psychological state of the observation group was better than that of the control group(P0.05).In 3 and June,the compliance of the patients in the observation group was better than that in the control group(P<0.05).Conclusion:continuous nursing intervention for patients with acute myocardial infarction after PCI can effectively adjust the unhealthy psychological state of patients,improve medication compliance and promote early rehabilitation of patients.

关键词： Acute myocardial infarction Postoperative PCI Continuous nursing Clinical effect

Robust Magnetic Field Loop Closure Detection for Low-Cost Robot’s Localization and Mapping

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Robust Magnetic Field Loop Closure Detection for Low-Cost Ro...

第十三届中国卫星导航年会

作者： Bin Yao Wen Li dongyan wei Xinchun Ji Wenchao Zhang Aerospace Information Research Institute Chinese Academy of Sciences University of Chinese Academy of Sciences

The robot realizes the perception of its own location through the fusion of multiple navigation sources. However, there are limits in application scenarios and cost for various navigation sources such as vision, laser, and inertial measurement unit. Therefore, a robust magnetic field loop closure detection for low-cost robot’s localization and mapping method is proposed in this paper. In front-end, The MEMS inertial measurement unit and wheel odometer are fused to estimate the pose state of the robot, and magnetic field sequence loop closure is detected in DTW algorithm, and a general graph optimization method is applied to optimize the pose in back-end. Experiments show that this method can effectively detect the magnetic sequence loop closures and eliminate the cumulative error in inertial recurrence, realize the long-time continuous indoor positioning of the robot.

关键词： Magnetic Sequence Loop Closure Graph Optimization Robot SLAM Multi-source Fusion

The robust heading of the foot-mounted PDR system assisted by anchor points

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The robust heading of the foot-mounted PDR system assisted b...

第十一届中国卫星导航年会

作者： Wenchao Zhang dongyan wei Hong Yuan Aerospace Information Research Institute Chinese Academy of Sciences University of Chinese Academy of Sciences

The Zero-velocity Update(ZUPT) aided Extended Kalman Filter(EKF) is commonly used in the classical INS-based foot-mounted PDR(Pedestrian Dead Reckoning) system.However,in the realistic test,the system

关键词： ZUPT-aidedEKF anchorpoints headingcalibration ZARU trajectorycalibration

On Biochemical Formation of Salt Deposits

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Acta Geologica Sinica(English Edition) 2000年第3期74卷 613-617页

作者： wei dongyan DENG Xiaolin LIU Zhenmin YANG Gengsheng Geological Institute for Chemical Minerals Zhuozhou 072754Hebei

A water/salt system in an evaporative environment is both a physicochemical region and a biological one. All the parameters of the system, such as the salinity, temperature and CO2 partial pressure, are affected by halophilic bacteria. The system controls salt deposition but is modified by an accompanying ecological system; therefore it should be called a water/salt/biological system. Salt minerals result from accumulation of the remains of bacteria/algae, namely, bacteria/algae formation; whereas biological, biophysical and biochemical processes provide full evidence for organic involvement. Consequently, salt deposits should not be called purely chemical but biological/chemical ones. This new argument supplements and develops the traditional idea and helps perfect the mineralization theory of salts and even general deposits, thus giving guidance to prospecting for salt deposits.

关键词： salt deposits biochemistry genesis

The PDR System Based on Improved QSF+Map Matching Algorithm

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The PDR System Based on Improved QSF+Map Matching Algorithm

第九届中国卫星导航学术年会

作者： Wenchao Zhang dongyan wei Peiwen Gong Hong Yuan University of Chinese Academy of Sciences Academy of Opto-electronics Chinese Academy of Sciences

The Zero-velocity Update(ZUPT) aided Extended Kalman Filter(EKF) is commonly used in the classical INS-based PDR system,which can effectively suppress the error growth of the inertial based pedestrian navigation systems.However,the system still suffers from the drift of heading error.The magnetic field is very useful to estimate the heading of the system,but the magnetic disturbance has a severely effect on the estimation.The Quasi-static magnetic Field(QSF) method was developed to estimate heading errors using magnetic field in perturbed environments,but the method may bring extra errors to system as the high false alarm probability of detecting the quasi-static field.In this paper,the improved QSF method is proposed to estimate the heading in the perturbed magnetic field.Also,the improved QSF method is combined with a compass filter,which can successfully extract the desired magnetic measurements and feedback them into the EKF to estimate the heading errors.At last,the iterative 2 D map matching method is proposed to refine the trajectory of the PDR system,which can effectively suppress the long-term drift errors of the trajectory.The experiment result shows that the trial trajectory closed error/length is 0.109%.

关键词： PDR system ZUPT-aided EKF QSF compass filter map matching

GNSS Satellite Selection Algorithm Revisited: A weighted Way with Integrity Consideration

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GNSS Satellite Selection Algorithm Revisited: A Weighted Way...

第四届中国卫星导航学术年会

作者： Liang Li Hong Yuan Chao Yuan dongyan wei wei Liu Academy of Opto-electronics Chinese Academy of Science

With the promising future of Global Navigation Satellite System （GNSS）, the quantity of available satellites could dramatically increase to more than 35. Tracking all available satellites simultaneously leads to unacceptable computation burden for standalone receivers. Most satellite selection methods were therefore proposed to release the computation load with the minimum satellites set to maintain endurable positioning accuracy under the least Dilution of Precision （DOP） loss criterion. In terms of safety-of-life （SoL） navigation services, the integrity monitoring is an indispensable function. The traditional satellite selection methods should therefore be enhanced to take account of positioning accuracy and the potential integrity loss from some fault satellite, which may originates from satellite clock anomaly drift or the deformation of signals in space, e.g. ionosphere scintillation. Giving the fact that the loss of some satellite may have little difference on the DOP, but could impose a negative influence on the integrity performance, satellite selection should therefore give an insight into the selection criterion and the determination of the threshold values. A novel satellite selection algorithm with using weighting method is presented to select the optimal satellites set with satisfying the requirement in both accuracy and integrity. The selection threshold values for DOP and integrity is deduced from the required navigation performance （RNP） defined by International Civil Aviation Organization （ICAO）. The performance of the proposed method was validated with using the simulated GNSS constellations. The accuracy and integrity also were compared with the typical existing satellite selection methods, i.e., maximum volume algorithm and quasi-optimal satellite selection algorithm, etc. The simulation results demonstrate that weighted satellites selection method could provide optimal satellites set with not only the better accuracy and less integrity loss, but also with a reasonable computation burden, and

关键词： GNSS satellite selection accuracy integrity DOP

Research on Barometric Altimeter Assisting GNSS Navigation for Urban Environments

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Research on Barometric Altimeter Assisting GNSS Navigation f...

第九届中国卫星导航学术年会

作者： Han Guo dongyan wei Guangzhou Ouyang Qifeng Lai

In the satellite navigation system,the altitude accuracy of an regular receiver is usually poor.This paper proposed a method that uses satellite positioning assisting differential barometric altimetry

关键词： Differential barometric altimetry Satellite positioning RAIM

A GM/DR Integrated Navigation Method for Vehicle Application

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A GM/DR Integrated Navigation Method for Vehicle Application

第十一届中国卫星导航年会

作者： Xinchun Ji dongyan wei Wen Li Yi Lu Hong Yuan Aerospace Information Research Institute Chinese Academy of Sciences

Focused on the independence and precision requirements for vehicle navigation, an integrated navigation scheme with geomagnetic matching(GM) and dead reckoning(DR) was proposed. The reference magnetic

关键词： geomagnetic matching integrated navigation