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Robust template feature matching method using motion-constrained DCF designed for visual navigation in asteroid landing

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Astrodynamics 2023年第1期7卷 83-99页

作者： yaqiong wang Xiongfeng Yan Zhen Ye Huan Xie Shijie Liu Xiong Xu Xiaohua Tong College of Surveying and Geo-Informatics and Shanghai Key Laboratory of Space Mapping and Remote Sensing for Planetary EaplorationTongji UniversityShanghai 200092China Shanghai Institute of Intelligent Science and Technology Shanghai 200092China

A robust and eficient feature matching method is necessary for visual navigation in asteroid-landing missions.Based on the visual navigation framework and motion characteristics of asteroids,a robust and efficient template feature matching method is proposed to adapt to feature distortion and scale change cases for visual navigation of asteroids.The proposed method is primarily based on a motion-constrained discriminative correlation filter(DCF).The prior information provided by the motion constraints between sequence images is used to provide a predicted search region for template feature matching.Additionally,some specific template feature samples are generated using the motion constraints for correlation filter learning,which is beneficial for training a scale and feature distortion adaptive correlation filter for accurate feature matching.Moreover,average peak-to-correlation energy(APCE)and jointly consistent measurements(JCMs)were used to eliminate false matching.Images captured by the Touch And Go Camera System(TAGCAMS)of the Bennu asteroid were used to evaluate the performance of the proposed method.In particular,both the robustness and accuracy of region matching and template center matching are evaluated.The qualitative and quantitative results illustrate the advancement of the proposed method in adapting to feature distortions and large-scale changes during spacecraft landing.

关键词： discriminative correlation filter(DCF) motion constraints feature distortion adaptive scale changes adaptive template feature matching

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Mechanical properties of rock materials with related to mineralogical characteristics and grain size through experimental investigation： a comprehensive review

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Frontiers of Structural and Civil Engineering 2017年第3期11卷 322-328页

作者： Wenjuan SUN Linbing wang yaqiong wang USTB-Virginia Tech Joint Lab on Multifunctional Materials National Center for Materials Service Safety University of Science and Technology Beijing Beijing China Virginia Tech Blacksburg VA 24061 United States Shaanxi Provincial Key Laboratory for Highway Bridge & Tunnel Chang'an University Xi'an 710064 China

Mechanical properties of rock materials are related to textural characteristics. The relationships between mechanical properties and textural characteristics have been extensively investigated for differently types of rocks through experimental tests. Based on the experimental test data, single- and multiple- variant regression analyses are conducted among mechanical properties and textural characteristics. Textural characteristics of rock materials are influenced by the following factors： mineral composition, size, shape, and spatial distribution of mineral grains, porosity, and inherent microcracks. This study focuses on the first two： mineral composition and grain size. This study comprehensively summarizes the regression equations between mechanical properties and mineral content and the regression equations between mechanical properties and grain size. Further research directions are suggested at the end of this study.

关键词： Mechanical properties rock material texture mineral characteristics

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Investigation of mechanical performance of prestressed steel arch in tunnel

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Frontiers of Structural and Civil Engineering 2017年第3期11卷 360-367页

作者： yaqiong wang Yunxiao XIN Yongli XIE Jie LI Zhifeng wang a School of Highway Shaanxi Provincial Major Laboratory for Highway Bridge & Tunnel Chang'an University Xi'an 710064 China Shaanxi Communication Technology Consulting Co. Ltd. Xi'an 710068 China

In the traditional tunneling method, the steel arch are often adopted to support surrounding rock to ensure the structural stability. If the steel arch is prestressed in time, tunnel support can effectively prevent the development of rock crack, thereby increasing the overall strength of tunnel support and suppress the deformation of the surrounding rock. Based on the mechanical model of steel arch established in this paper, the stress distribution of steel arch is investigated via the numerical simulation method, and the impact on surrounding rock is also analyzed. Through a field test, the rules of the arch strain distribution are observed and discussed. The results show that the prestressed steel arch structure can provide effective support and the stress gradually decreases from stress point to another arch springing. Furthermore, the stress distribution applied by the prestressed steel arch on the surrounding rock is uniform in a certain extent, and it is suggested that this construction method utilizing the prestressed steel arch to squeeze surrounding rock is feasible from a theoretical view.

关键词： tunnel support prestressing force steel arch numerical analysis

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Preparation and characterization of carbonyl iron/strontium hexaferrite magnetorheological fluids

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Particuology 2015年第5期13卷 134-144页

作者： Jianrong Liu Xianjun wang Xia Tang Ruoyu Hong yaqiong wang Wenguo Feng College of Chemistry Chemical Engineering and Materials Science &Jiangsu Provincial Key Laboratory of Organic SynthesisSoochow University School of Chemical Engineering Fuzhou University Jiangsu Provincial Key Laboratory of Environmental Materials and Engineering Yangzhou University Suzhou Nanocomp Inc.

The heat transfer oil-based magnetorheological fluid （MRF） was prepared using oleic acid-modified micron carbonyl iron powder as a magnetic dispersed phase and strontium hexaferrite （SrFe12019） nanoparticles as an additive. The sedimentation stability of MRFs was studied. The results indicated that the stability of MRFs was improved remarkably by adding SrFel2019 nanoparticles and the sedimenta- tion ratio was only 0.88 in 20 days when the content of nanoparticles reached 10wt%. The rheological properties were characterized by a HAAKE rheometer without a magnetic field and a capillary rheometer with and without a magnetic field. The effects of SrFe12019 nanoparticles, the temperature, and magnetic field strength were investigated. In addition, the rheological properties could be predicted well using the improved Herschel-Bulkley model, even under a magnetic field. A theoretical model was also proposed to predict the yield stress based on the microstructure of the MRF under an applied magnetic field.

关键词： Strontium hexaferrite Magnetorheological fluid Stability Rheological property

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High-precision geochronological constraints on the duration of ‘Dinosaur Pompeii’ and the Yixian Formation

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National Science Review 2021年第6期8卷 117-119页

作者： Yuting Zhong Magdalena H.Huyskens Qing-Zhu Yin yaqiong wang Qiang Ma Yi-Gang Xu State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences CAS Center for Excellence in Deep Earth Science Department of Earth and Planetary Sciences University of California at Davis State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of Sciences State Key Laboratory of Geological Processes and Mineral Resources School of Earth SciencesChina University of Geosciences

The Early Cretaceous Jehol Biota,renowned for its exceptionally wellpreserved volcanic-influenced ecosystem, was buried in lacustrine and occasionally fluvial sediments. This includes, notably, the Huajiying, Yixian and Jiufotang Formations in northern Hebei and western Liaoning and equivalent ash-interbedding sediments in neighboring areas [1–3](Fig. 1). It harbors many evolutionarily significant taxonomies, e.g. feathered dinosaurs,early birds, mammals and flowering plants, representing one of the most diversified terrestrial biotas of the Mesozoic [1,2,4].

关键词： JEHOL BIOTA

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Influence of species,age and weight on the establishment of a murine model of brachial plexus root avulsion

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Neural Regeneration Research 2010年第10期5卷 764-768页

作者： Lifeng Yan Xiuchun Zhao yaqiong wang Lin wang Xiao Cheng Lihua Zhou Xia Feng Department of Human Anatomy Zhongshan School of Medicine Sun Yat-sen University Guangzhou 510080 Guangdong Province China Department of Anesthesiology First Affiliated Hospital of Sun Yat-sen University Guangzhou 510080 Guangdong Province China

BACKGROUND： Animal models of brachial plexus root avulsion are required for the study of brachial plexus root injuries. The established ventral approach results in slight injuries, and is similar to mechanisms underlying human brachial plexus root avulsion.OBJECTIVE： To analyze the effects of weight, age, and species on the success rate of brachial plexus root avulsion, and to determine the perfect method for establishing models of brachial plexus root avulsion.DESIGN, TIME AND SETTING： A randomized, block design was performed at the Laboratory of Professor Lihua Zhou, Zhongshan School of Medicine, Sun Yat-sen University, China from June 2008 to June 2009.MATERIALS： Sprague Dawley （SD） rats, golden hamsters, and BALb/C mice were used in the present study.METHODS： All animals were randomly subjected to classical brachial plexus root avulsion and modified brachial plexus root avulsion.MAIN OUTCOME MEASURES： Success rate of brachial plexus root avulsion. RESULTS： The success rate of brachial plexus root avulsion was greater in the modified group than in the classical group （P〈0.01）. Moreover, the difference was significant in 15-day-old SD rats, 5-week-old SD rats, and 3-month-old BALb/C mice （P〈0.01）. The success rate of brachial plexus root avulsion was greater in the same weight, 15-day-old juvenile SD rats, than in the 3-month-old BALb/C mice （classical group, P〈0.01; modified group, P〈0.05）. The success rate of brachial plexus root avulsion was significantly greater in 3-month-old golden hamsters than in 5-week-old SD rats in the classical group （P〈0.05）. The success rate of brachial plexus root avulsion was significantly lower in the 15-day-old SD rats compared with the 5-week-old and 3-month-old SD rats in the classical group （P〈0.01）. However, there was no significant difference in the success rate of brachial plexus root avulsion between various ages of SD rats in the modified group （P〉0.05）.CONCLUSION： Modified surgery to induce brachial plexus root avulsion significantly increases the success rate of mode

关键词： brachial plexus root injury species age animal disease model modified surgery peripheral nerve injury neural regeneration

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The brackish-water bivalve Waagenoperna from the Lower Jurassic Badaowan Formation of the Junggar Basin and its palaeoenvironmental and palaeogeographic significance

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Geoscience Frontiers 2013年第1期4卷 95-103页

作者： Yanhong Pan Jingeng Sha yaqiong wang Xiaolin Zhang Xiaogang Yao Bo Peng Xin Rao State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of Sciences

The brackish-water bivalve Waagenoperna Tokuyama, 1959 is reported from the Lower Jurassic Badaowan Formation at four localities, along the southern margin and western margin of the Junggar Basin. Taphonomic features recorded in the field indicate that it occurs in autochthonous or parautochthonous assemblages. The autecology of Waagenoperna therefore yields information on the palaeoenvironment of the area. The restriction of Waagenoperna to marine and brackish-water settings suggests that the sea water once reached these areas during the Sinemurian. This paper discusses the palaeogeographic implications and suggests an ingression of the sea water from the west to the western and southern part of the Junggar Basin. Additionally, the two Waagenoperna species collected from the Haojiagou section in the Junggar Basin are taxonomically documented.

关键词： Brackish-water bivalve Waagenoperna Transgression Sinemurian Junggar Basin

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中全新世福建沿海地区海平面波动:基于NDQK5岩芯介形类化石记录

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地质学报 2024年第2期98卷 333-345页

作者：贾宝岩彭博王继龙于俊杰周保春赵泉鸿李保华王亚琼中国科学院南京地质古生物研究所现代古生物学与地层学国家重点实验室江苏南京210008 中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室江苏南京210008 中国科学院大学北京100049 中国地质调查局南京地质调查中心江苏南京210016 上海自然博物馆(上海科技馆分馆) 上海200041 同济大学海洋地质国家重点实验室上海200092

福建沿海地区第四系较为发育,是研究晚更新世以来相对海平面变化的理想区域。本文以福建宁德NDQK5岩芯中产出的高分辨率介形类化石为研究对象,结合加速器质谱法(accelerator mass spectrometry,AMS)14C和光释光测年技术建立岩芯年代框架... 详细信息

福建沿海地区第四系较为发育,是研究晚更新世以来相对海平面变化的理想区域。本文以福建宁德NDQK5岩芯中产出的高分辨率介形类化石为研究对象,结合加速器质谱法(accelerator mass spectrometry,AMS)14C和光释光测年技术建立岩芯年代框架,重建了中全新世期间福建沿海地区的相对海平面变化。结果显示,NDQK5岩芯中的介形类化石记录主要分布于4~17.1 m段,对应年代约为8.2~6.9 ka BP。岩芯内共计识别出海相介形类23属26种,根据优势种以及特征种的相对丰度变化特征可将岩芯内的介形类动物群划分为3个组合:①介形类组合A以Bicornucythere bisanensis和Sinocytheridea impressa为主,代表潮下带环境;②介形类组合B以Sinocytheridea impressa和Neomonoceratina delicata为优势种,指示近岸内陆架的沉积环境;③介形类组合C以Sinocytheridea impressa和Loxoconcha ocellifera为主,代表潮间带的沉积环境。基于介形类组合的分布特征,本文推断福建沿海地区海平面约在8.2~7.4 ka BP期间持续上升,并在约7.9~7.4 ka BP区间达到最高;7.4~7.0 ka BP期间海平面下降,随后再次上升。因此,介形类化石记录指示福建沿海地区在全新世高海平面背景下依然存在相对海平面的次一级波动。同时,结合已有福建沿海地区海平面变化驱动机制的研究结果,本研究推断8.2~7 ka BP期间福建沿海地区的海平面变化可能主要受控于冰盖融水;7 ka BP后该地区的海平面波动可能受控于“冰川-水均衡调整”作用。

关键词：宁德东海 MIS 1 中全新世高海平面介形类组合

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PERMA模式在慢性病病人中的应用进展

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循证护理 2024年第12期10卷 2142-2145页

作者：王晴李莉莉王亚琼河南科技大学护理学院河南471023 河南科技大学第一附属医院

总结积极情绪、投入、人际关系、意义及成就(PERMA)模式的概述、理论基础、测量工具及其在慢性病病人中的应用,以期为临床促进慢性病病人的心理健康、提升生活质量提供参考。

关键词： PERMA模式慢性病心理干预综述护理

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基于运动恢复结构的小行星三维重构和形貌分析

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智能计算机与应用 2024年第4期14卷 136-140页

作者：张今王亚琼陈杰上海市航天测绘遥感与空间探测重点实验室上海200092 同济大学测绘与地理信息学院上海200092

小行星探测已成为深空探测中重要内容,三维重建是小行星探测过程中的关键步骤,对探测器导航、探测区域选址、引力场建模等均具有重要意义。本文研究了利用运动恢复结构的小行星三维重构方法,利用小行星162173Ryugu与25143Itokawa的探测... 详细信息

小行星探测已成为深空探测中重要内容,三维重建是小行星探测过程中的关键步骤,对探测器导航、探测区域选址、引力场建模等均具有重要意义。本文研究了利用运动恢复结构的小行星三维重构方法,利用小行星162173Ryugu与25143Itokawa的探测数据构建了其三维形状重构,分析了建模结果,探索了改进方式,并根据重构结果对162173Ryugu进行了形貌分析,对162173Ryugu表面的陨石坑进行了识别与分类。研究表明,利用运动恢复结构方法可以有效地构建小行星的三维形貌,支撑小行星探测任务。

关键词：小行星探测三维形状重构形貌分析运动恢复结构

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