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去偏转换方向余弦位置和多普勒量测跟踪

哈尔滨工业大学学报 2016年第10期48卷 97-102页

作者：付锦斌孙进平魏少明李少洪北京航空航天大学电子信息工程学院北京100191

为解决相控阵雷达方向余弦坐标系下状态空间模型量测方程强非线性的问题,提出了一种带多普勒量测的去偏转换量测跟踪方法.在考虑距离量测误差与多普勒量测误差相关性的基础上,用距离量测与多普勒量测的乘积构造伪量测来减轻多普勒量测... 详细信息

为解决相控阵雷达方向余弦坐标系下状态空间模型量测方程强非线性的问题,提出了一种带多普勒量测的去偏转换量测跟踪方法.在考虑距离量测误差与多普勒量测误差相关性的基础上,用距离量测与多普勒量测的乘积构造伪量测来减轻多普勒量测的非线性.并通过对方向余弦进行二阶泰勒展开,得到了转换量测误差均值和协方差的一致性估计.最后通过对位置量测和伪量测进行序贯处理解决了伪量测非线性的问题.仿真结果证明:通过引入多普勒量测确实提高了滤波性能;同时相比于常用的扩展卡尔曼滤波器和不敏卡尔曼滤波器,提出的去偏转换量测滤波器在方向余弦坐标系下具有更好的跟踪性能.

关键词：目标跟踪相控阵雷达方向余弦坐标系多普勒量测去偏转换量测

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针对机动目标的改进UFIR跟踪算法

北京航空航天大学学报 2015年第1期41卷 77-82页

作者：付锦斌孙进平卢松涛张耀天北京航空航天大学电子信息工程学院北京100191 爱荷华州立大学电子与计算工程系安姆斯50011

在机动目标跟踪中,卡尔曼滤波器(KF)及其改进算法的性能依赖于过程噪声统计特性的准确性,若模型过程噪声与实际存在偏差,通常会出现估计误差增大甚至发散的现象.无偏有限冲击响应滤波器(UFIR)在滤波过程中无需过程噪声统计特性的先验知... 详细信息

在机动目标跟踪中,卡尔曼滤波器(KF)及其改进算法的性能依赖于过程噪声统计特性的准确性,若模型过程噪声与实际存在偏差,通常会出现估计误差增大甚至发散的现象.无偏有限冲击响应滤波器(UFIR)在滤波过程中无需过程噪声统计特性的先验知识,将其应用于机动目标跟踪中,针对现有UFIR滤波器中广义噪声功率增益(GNPG)不随量测新息变化的问题,设计了一种根据相邻时刻量测新息比值动态调整GNPG的改进UFIR滤波器,改善了UFIR滤波器的机动检测能力.仿真结果表明,当假定过程噪声准确时,现有和改进UFIR滤波器与KF的跟踪性能相似;但当假定过程噪声不准确时,改进UFIR滤波器具有最佳的滤波效果.

关键词：机动目标跟踪无偏有限冲击响应滤波器卡尔曼滤波器广义噪声功率增益自适应

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基于滑模控制的制导方法研究

战术导弹技术 2016年第5期 68-72页

作者：黄兴冀四梅付锦斌北京理工大学宇航学院北京100081

针对空地导弹末制导段终端角约束问题,根据滑模控制理论,设计了加速度控制指令垂直于弹目视线方向的制导规律。从建立末制导过程中导弹和目标间的动力学方程入手,推导出以视线角和视线角速度为状态量的状态方程,构建了一个滑模面,在这... 详细信息

针对空地导弹末制导段终端角约束问题,根据滑模控制理论,设计了加速度控制指令垂直于弹目视线方向的制导规律。从建立末制导过程中导弹和目标间的动力学方程入手,推导出以视线角和视线角速度为状态量的状态方程,构建了一个滑模面,在这个滑模面上弹目视线角和期望的终端角之差与弹目视线角速度为零。又引入Lyapunov函数驱动系统达到所设计的滑模面,综上推导出控制加速度的表达形式。该导引律在满足终端角要求的同时,能进一步增大导弹击顶速度。最后,在MATLAB环境下构建了几种仿真场景,仿真结果表明该制导律的有效性。

关键词：空地导弹滑模控制制导方法

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死亡提醒效应的心理机制及影响因素

心理科学 2011年第2期34卷 461-464页

作者：傅晋斌郭永玉华中师范大学心理学院暨湖北省人的发展与心理健康重点实验室武汉430079

死亡提醒效应是指个体在死亡提醒后会产生世界观防御或自尊寻求的一种普遍现象。其心理机制是以死亡想法通达性为指标的潜在死亡焦虑,影响因素则包括年龄、宗教信仰、结构需求、自我控制、依恋类型等个体差异和不同的情境启动。未来研... 详细信息

死亡提醒效应是指个体在死亡提醒后会产生世界观防御或自尊寻求的一种普遍现象。其心理机制是以死亡想法通达性为指标的潜在死亡焦虑,影响因素则包括年龄、宗教信仰、结构需求、自我控制、依恋类型等个体差异和不同的情境启动。未来研究应解释与死亡无直接关联的刺激可引发类似效应的原因,进一步阐释与证实潜在的死亡焦虑,并明确自尊对死亡提醒效应的影响。

关键词：死亡提醒效应死亡想法通达性恐惧管理理论

死亡提醒效应:概念、测量及来自多领域的证据

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心理学探新 2011年第2期31卷 113-117页

作者：郭永玉傅晋斌华中师范大学心理学院暨湖北省人的发展与心理健康重点实验室武汉430079

死亡提醒效应是指由于死亡提醒而引起的世界观防御或自尊寻求。对死亡提醒效应的测量主要考察死亡提醒后,被试在世界观防御或自尊寻求上的反应。死亡提醒效应在健康、消费、司法、政治及和平领域均有所体现,并对现实生活富有启示作用。... 详细信息

死亡提醒效应是指由于死亡提醒而引起的世界观防御或自尊寻求。对死亡提醒效应的测量主要考察死亡提醒后,被试在世界观防御或自尊寻求上的反应。死亡提醒效应在健康、消费、司法、政治及和平领域均有所体现,并对现实生活富有启示作用。未来研究应细化世界观的概念,并借鉴本土文化中的生死观。

关键词：死亡提醒效应世界观防御自尊寻求恐惧管理理论

The protective effect and crucial biological pathways analysis of Trametes lactinea mycelium polysaccharides on acute alcoholic liver injury in mice based on transcriptomics and metabonomics

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Food Science and Human Wellness 2021年第4期10卷 480-489页

作者： jinbin Hao Liyun Ye Guoliang Meng Yanjiao Song Junsheng fu Xiaoping Wu College of Life Sciences Fujian Agriculture and Forestry UniversityFuzhou350002 FujianChina

Trametes lactinea mycelia polysaccharides(TLMPS)have a wide range of *** potential mechanisms of action of TLMPS against acute alcohol-induced liver injury in vivo were investigated by analyzing the physical and chemical properties of TLMPS and its protective effects on a mouse model of alcoholic liver *** protected the liver against alcohol-induced injury,as evidenced by the reduced alcohol-induced elevation of the liver index,serum biochemical indices,and maintenance of hepatic *** mechanisms were analyzed using transcriptome and metabolome *** transcriptome data revealed the involvement of many differentially expressed genes in chemical carcinogenesis,drug metabolism,and metabolism of xenobiotics by cytochrome *** metabolome analysis revealed that TLMPS significantly regulated specific metabolites in the liver,including organic acids,lipids,nucleosides,and organic oxygen *** enrichment analysis revealed the signifi cant involvement of different metabolites in choline metabolism,ATP-binding cassette transporters,and glycerophospholipid *** of the changes in gene expression and metabolites revealed the significantly different expression of several genes encoding key enzymes and metabolites in choline metabolism *** collective fi ndings confi rmed that choline metabolism plays an important role in the protective effects of TLMPS against acute alcoholic liver injury.

关键词： Trametes lactinea Polysaccharide Hepatoprotective Transcriptome Metabolome

An improved social force model (ISFM)-based crowd evacuation simulation method in virtual reality with a subway fire as a case study

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International Journal of Digital Earth 2023年第1期16卷 1186-1204页

作者： jinbin Zhang Jun Zhu Pei Dang Jianlin Wu Yuxuan Zhou Weilian Li Lin fu Yukun Guo Jigang You Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduPeople’s Republic of China Institute of Geodesy and Geoinformation University of BonnBonnGermany School of Engineering and Geomatics Southwest Petroleum UniversityChengduPeople’s Republic of China

Crowd evacuation simulation using virtual reality(VR)is significant for digital emergency response ***,existing evacuation simulation studies suffer from poor adaptation to complex environments,inefficient evacuations,and poor simulation effects and do not fully consider the impacts of specific disaster environments on crowd *** more realistically express the crowd evacuation results obtained under the influence offire environments and the subjective consciousness of pedestrians in subway stations,we designed a dynamic pedestrian evacuation path planning method under multiple constraints,analysed the influences of an‘environmental role’and a‘subjective initiative’on crowd evacuation,established an improved social force model(ISFM)-based crowd evacuation simulation method in VR,developed a prototype system and conducted experimental *** experimental results show that the crowd evacuation time of the ISFM is affected by the disaster *** simulation experiments without disaster scenarios,the improved model’s crowd evacuation efficiency improved by averages of 12.53%and 15.37%over the commercial Pathfinder software and the original social force model,*** method described herein can effectively support real-time VR crowd evacuation simulation under multiexit and multifloor conditions and can provide technical support for emergency evacuation learning and management decision analyses involving subwayfires.

关键词： Subway stationfire improved social force model crowd evacuation simulation virtual reality path planning

MHD and kinetic analysis of flow bursts in the Earth's plasma sheet

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Science China(Technological Sciences) 2014年第1期57卷 55-66页

作者： MA YuDuan CAO jinbin fu HuiShan REME H. DANDOURAS I. YANG JunYing WANG ZhiQiang TAO Dan YANG Jian School of Astronautics Beihang University SOA Key Laboratory for Polar Science Polar Research Institute of China University of Toulouse UPS-OMP IRAP Toulouse 31028 France The French National Centre for Scientific Research The Research Institute in Astrophysics and Planetology BP 44346F-31028 Toulouse cedex 4 France Nanjing University of Aeronautics and Astronautics

In an attempt to study the flow bursts in the Earth＇s plasma sheet we select an event that took place on August 7, 2004 in the expansion phase of a substorm, using data from the geomagnetic index, solar wind data, plasma and magnetic field observa- tions from C1 Cluster satellite （the Cluster mission has 4 satellites） and from Double Star TC-1 satellite. In MHD approach, TC-1 firstly observed the tailward flow, then the earthward, and finally the flow altemated in two directions. C1 firstly ob- served the earthward plasma flow, and then the tailward plasma flow. Before flow bursts are observed by TC-1 and C1, there are disturbances in local entropy with their tailward local entropy larger than those of the earthward. The kinetic features of the plasma flow observed by C1 are similar to those in MHD. However, kinetic characteristics of the plasma flow observed by TC-1 are far more than the description in MHD. The inadequacy mainly exists in two cases：（i） the firstly enhanced tailward flows given in MHD are found without significant increase of the energetic tailward flux; （ii） the almost stagnant flow in MHD is composed of the enhanced energetic ion flux in both earthward and tailward directions. The earthward flow burst observed by TC-1 might be multiple overshoots and rebounds. The earthward flow burst observed by C1 might be simply rebounded in the near-Earth. The pulsation observed by C1 is earlier than that observed by TC-1 with the former intensity less than that of the latter. After the energetic ion flux in the tailward direction is significantly enhanced, the power spectrum intensity of the ULF wave commences to increase obviously, which may suggest that the stream instability is closely correlated with ULF pulsations.

关键词： MHD kinetic flux entropy

A dynamic holographic modelling method of digital twin scenes for bridge construction

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International Journal of Digital Earth 2023年第1期16卷 2404-2425页

作者： Jianlin Wu Jun Zhu jinbin Zhang Pei Dang Weilian Li Yukun Guo Lin fu Jianbo Lai Jigang You YaKun Xie Ce Liang Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduPeople’s Republic of China Institute of Geodesy and Geoinformation University of BonnBonnGermany School of Engineering and Geomatics Southwest Petroleum UniversityChengduPeople’s Republic of China Institute of Computing Technology China Academy of Railway Sciences CoLtdBeijingPeople’s Republic of China

Holographic projection technology can provide a more intuitive and efficient visualization effect for a digital twin bridge construction ***,pre-rendering methods in the existing research work are usually used to implement holographic visualization,which is static *** above-mentioned methods for static display have many shortcomings,such as poor adaptability,low rendering efficiency and lack of real-time.A dynamic holographic modelling approach is proposed for the augmented visualization of digital twin scenes for bridge ***,a dynamic segmentation algorithm with adaptive screen size was designed to high-efficiently generate holographic ***,a motion blur control method was designed to improve the rendering efficiency of holographic scenes according to human visual ***,a prototype system was developed,and the corresponding experimental analysis was *** experimental results show that the method proposed in this article can support adaptive screen size image segmentation and real-time generation of holographic scenes for bridge *** amount of scene data can be reduced to more than 30%,which significantly improves rendering efficiency and reduces glare.

关键词： Bridge construction Digital twins Holographic scene Adaptive segmentation Rendering optimization