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Multi‑level autonomous integrity monitoring method for multi‑source PNT resilient fusion navigation

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Satellite Navigation 2023年第3期4卷 210-226页

作者： rui chen Long Zhao School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

For the integrity monitoring of a multi-source PNT(Positioning,Navigation,and Timing)resilient fusion navigation system,a theoretical framework of multi-level autonomous integrity monitoring is *** to the mode of multi-source fusion navigation,the framework adopts the top-down logic structure and establishes the navigation source fault detection model based on the multi-combination separation residual method to detect and isolate the fault source at the system level and subsystem *** isolated non-redundant navigation sources,the system level recovery verification model is *** the isolated multi-redundant navigation sources,the sensor fault detection model optimized with the dimension-expanding matrix is used to detect and isolate the fault sensors,and the isolated fault sensors are verified in ***,according to the fault detection and verification results at each level,the observed information in the fusion navigation solution is dynamically *** this basis,the integrity risk dynamic monitoring tree is established to calculate the Protection Level(PL)and evaluate the integrity of the multi-source integrated navigation *** autonomous integrity monitoring method proposed in this paper is tested using a multi-source navigation system integrated with Inertial Navigation System(INS),Global Navigation Satellite System(GNSS),Long Baseline Location(LBL),and Ultra Short Baseline Location(USBL).The test results show that the proposed method can effectively isolate the fault source within 5 s,and can quickly detect multiple faulty sensors,ensuring that the positioning accuracy of the fusion navigation system is within 5 m,effectively improving the resilience and reliability of the multi-source fusion navigation system.

关键词： Autonomous integrity monitoring Fault detection and isolation Multi-source PNT resilient fusion navigation Protection level

A No Shrinking Breather Theorem for Noncompact Harmonic Ricci Flows

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Acta Mathematica Sinica,English Series 2023年第10期39卷 1939-1950页

作者： Jia rui chen Qun chen School of Mathematics and Statistics Wuhan UniversityWuhan 430072P.R.China

In this paper,we construct an ancient solution by using a given shrinking breather and prove a no shrinking breather theorem for noncompact harmonic Ricci flow under the condition that Sic:=Ric−α∇φ⊗∇φis bounded fro... 详细信息

关键词： Harmonic Ricci flow ancient solution breather

On the half-quantized Hall conductance of massive surface electrons in magnetic topological insulator films

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 127-136页

作者： rui chen Shun-Qing Shen Department of Physics The University of Hong KongHong Kong 999077China Department of Physics Hubei UniversityWuhan 430062China

In topological insulators,massive surface states resulting from local symmetry breaking were thought to exhibit a half-quantized Hall conductance,obtained from the low-energy effective model in an infinite Brillouin *** a lattice model,the surface band is composed of a combination of surface states and bulk *** massive surface states alone may not be enough to support an exact one-half quantized surface Hall conductance in a finite Brillouin zone and the whole surface band always gives an integer quantized Hall conductance as enforced by the TKNN *** explore this,we investigate the band structures of a lattice model describing the magnetic topological insulator film that supports the axion insulator,Chern insulator,and semi-magnetic topological insulator *** reveal that the gapped and gapless surface bands in the three phases are characterized by an integer-quantized Hall conductance and a half-quantized Hall conductance,*** propose an effective model to describe the three phases and show that the low-energy dispersion of the surface bands inherits from the surface Dirac *** gapped surface band manifests a nearly half-quantized Hall conductance at low energy near the center of Brillouin zone,but is compensated by another nearly half-quantized Hall conductance at high energy near the boundary of Brillouin zone because a single band can only have an integer-quantized Hall *** gapless band hosts a zero Hall conductance at low energy but is compensated by another half-quantized Hall conductance at high energy,and thus the half-quantized Hall conductance can only originate from the gapless ***,we calculate the layer-resolved Hall conductance of the *** conclusion suggests that the individual gapped surface band alone does not support the half-quantized surface Hall effect in a lattice model.

关键词： magnetic topological insulator Dirac equation half-quantized Hall conductance

A self-healing and conductive ionic hydrogel based on polysaccharides for flexible sensors

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Chinese Journal of Chemical Engineering 2023年第1期53卷 73-82页

作者： Yufei Wang Zihao chen rui chen Jie Wei Beijing Engineering Research Center for the Synthesis and Applications of Waterborne Polymers Beijing 100029China Key Laboratory of Carbon Fibers and Functional Polymers Ministry of EducationBeijing 100029China College of Materials Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

In this study,we proposed a self-healing conductive hydrogel based on polysaccharides and Li+to serve as flexible *** first,the oxidized sodium alginate(OSA)was obtained through the oxidation reaction of sodium alginate(SA).Then OSA,carboxymethyl chitosan(CMC),and agarose(AGO)were dissolved in LiCl solution,***,the hydrogel was obtained through heating,mixing,and cooling *** of the Schiff base structure and hydrogen bonding,the hydrogel demonstrates good mechanical and self-healing *** presence of Li+provides good conductivity for the *** addition,we demonstrated the application of the hydrogel as the flexible *** can perceive the process of pressing Morse code with the index finger as a pressure sensor and monitor sliding movement of the thumb as the strain sensor to browse the web with the mobile ***,the selfhealing conductive hydrogel may have potential applications in flexible wearable sensors.

关键词： Hydrogel Self-healing Conductivity Polysaccharide Flexible sensor

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自激式电感耦合等离子体光源设计及光谱分析

光谱学与光谱分析 2025年第1期45卷 66-71页

作者：卢思贤龙开红詹陈锐李明北方工业大学电气与控制工程学院北京100144 益阳职业技术学院电子与信息工程学院湖南益阳413055

电感耦合等离子体(ICP)光谱仪是一种应用范围很广的元素分析仪,主要用于元素定性与定量的分析。ICP光源是光谱仪的核心部件,它在光谱仪中扮演着至关重要的角色。目前主流的ICP光源有两种:自激式和他激式,各自具有优缺点。他激式光源电... 详细信息

电感耦合等离子体(ICP)光谱仪是一种应用范围很广的元素分析仪,主要用于元素定性与定量的分析。ICP光源是光谱仪的核心部件,它在光谱仪中扮演着至关重要的角色。目前主流的ICP光源有两种:自激式和他激式,各自具有优缺点。他激式光源电路复杂、体积庞大、阻抗匹配速度较慢、最大输出功率有限。设计了一种基于镀金工艺的高功率MOSFET和变频实现阻抗匹配的自激式ICP光源,该光源采用射频放大和阻抗匹配一体化的设计,把从负载线圈采样的频率信号f_(1)以及功率放大电路放大后的频率相位f_(0)进行相位比较,再根据两者相位差的变化,进而控制频率的变化,实现阻抗匹配;设计上采用了镀金工艺的金属化硅N通道型高功率的MOSFET实现功率放大,具有更大的功率密度、更小的体积,最大输出功率超过2400 W。对研制的ICP光源进行了电学静态测试,给出了鉴相器、压控振荡器以及功率的输出特性,验证了各电路在相应工作状态下的性能表现;同时结合光谱仪进行了包含Ba、Na和Li元素标准溶液的测试,获得了目标元素的光谱信号;另外,对获得的光谱信号进行了处理,使用了基于EEMD特征增强的方法对目标元素光谱信号进行有效增强,信号的线性决定系数(R^(2))从0.97降至0.99,相对标准偏差(RSD)从6.47%降至1.07%,增强了信号的准确性和可用性。本文所研制的自激式ICP光源,通过射频放大和阻抗匹配一体化设计缩小了体积,变频技术使阻抗匹配速度从毫秒级提升到纳秒级,镀金工艺的MOSFET技术使最大输出功率从原来的1800 W增加到2400 W,为ICP光源的进一步优化和应用奠定了基础,具有重要的科学研究和工程实践意义。

关键词：自激式ICP光源阻抗匹配光谱信号 EEMD算法

Facile synthesis of coordination polymer nanocubes and their conversion into mesoporous single crystal-like Y_2O_3 nanocubes

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Chinese Chemical Letters 2014年第6期25卷 869-873页

作者： rui chen Tie-Hong chen Institute of New Catalytic Materials Science Key Laboratory of Advanced Energy Materials Chemistry(MOE)College of ChemistryCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Nankai University

Mesoporous single crystal-like Y2O3 nanocubes have been prepared through a coordination-based self- assembly process. Firstly, a uniform nanocube-like Y-lysine precursor was simply prepared with hydrothermal treatment. After the simple thermal treatment process, nanocube-shaped yttrium oxides with the morphology inherited from the Y-lysine precursor were successfully prepared. The phase, morphology, size and crystalline structure were well characterized by XRD, SEM and TEM. N2 adsorption-desorption demonstrates the mesoporous characteristics of the Y2O3 nanocubes, showing a relatively high surface area of 60 m^2/g.

关键词： Mesoporous Y2O3 Single crystal Nanocube Template-free

Big Theta Equals Small Theta Generically

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Acta Mathematica Sinica,English Series 2024年第3期40卷 717-730页

作者： rui chen Jia Liang ZOU Institute for Advanced Study in Mathmatics Zhejiang UniversityHangzhou 310058P.R.China Department of Mathematics University of Michigan530 Church StAnn ArborMI 48109USA

In this paper we consider the theta correspondence over a non-Archimedean local *** the homological method and the theory of derivatives,we show that under a mild condition the bigtheta lift is irreducible.

关键词： Theta correspondence derivatives

A Modified Cellular Automaton Model for the Quantitative Prediction of Equiaxed and Columnar Dendritic Growth

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Journal of Materials Science & Technology 2014年第12期30卷 1311-1320页

作者： rui chen Qingyan Xu Baicheng Liu Key Laboratory for Advanced Materials Processing Technology School of Materials Science and Engineering Tsinghua University

Since the characteristic of dendrite is an important factor determining the performance of castings, a twodimensional cellular automaton model with decentered square algorithm is developed for quantitatively predicting the dendritic growth during solidification process. The growth kinetics of solid/liquid interface are determined by the local equilibrium composition and local actual liquid composition, and the calculation of the solid fraction increment is based on these two compositions to avoid the solution of growth velocity. In order to validate the developed model, quantitative simulations of steady-state dendritic features over a range of undercooling was performed and the results exhibited good agreement with the predictions of LGK（Liptone Glicksman-Kurz） model. Meanwhile, it is demonstrated that the proposed model can be applied to simulate multiple equiaxed dendritic growth, as well as columnar dendritic growth with or without equiaxed grain formation in directional solidification of AleC u alloys. It has been shown that the model is able to simulate the growth process of multi-dendrites with various preferential orientations and can reproduce a wide range of complex dendritic growth phenomena such as nucleation, coarsening of dendrite arms, side branching in dendritic morphologies, competitive growth as well as the interaction among surrounding dendrites.

关键词： Cellular automaton Dendritic growth Crystallographic orientation Aluminum alloys

Low Cost 1D DCT Core for Multiple Video Codec

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Chinese Journal of Electronics 2016年第6期25卷 1052-1057页

作者： JIA rui chen rui LIN Colin Yu GUO Zhenhong YANG Haigang Institute of Electronics Chinese Academy of Sciences The University of Chinese Academy of Sciences

The expandability of high demands for multimedia applications brings out more and more video standards for improving the coding and compression efficiency. As the most commonly used transform, Discrete cosine transform(DCT) achieves excellent energy compaction property and good compression efficiency. Hardware sharing is the mostly used efficient strategy to reduce the cost for video codec. Based on traditional matrix factorization, this paper makes three observations to direct the design of proposed hardware sharing architecture. The proposed architecture can be generally used to compute 8×8 DCT of AVS, H.264, VC-1 and HEVC in a low cost way, and can be used to decode Full-HD and WQXGA formate video sequences in real time. The design has been synthesized in 0.13μm technology. The synthesis results show that the proposed architecture achieves76.9% reduction in gate count, 85.6% decrease in power consumption and 35% improvement in operational speed in comparison with other existing designs.

关键词： Discrete cosine transform(DCT) 8×8 integer transform AVS H.264 VC-1 HEVC Hardware sharing