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Robust Iterated Sigma Point FastSLAM Algorithm for Mobile Robot Simultaneous Localization and Mapping

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Chinese Journal of Mechanical Engineering 2011年第4期24卷 693-700页

作者： song yu song Yongduan LI Qingling Center for Intelligent System and Renewable Energy Beijing Jiaotong University Beijing 100044 China State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin 150080 China Institute of Automation Chinese Academy of Sciences Beijing 100190 China

Simultaneous localization and mapping （SLAM） is a key technology for mobile robots operating under unknown environment. While FastSLAM algorithm is a popular solution to the SLAM problem, it suffers from two major drawbacks： one is particle set degeneracy due to lack of observation information in proposal distribution design of the particle filter; the other is errors accumulation caused by linearization of the nonlinear robot motion model and the nonlinear environment observation model. For the purpose of overcoming the above problems, a new iterated sigma point FastSLAM （ISP-FastSLAM） algorithm is proposed. The main contribution of the algorithm lies in the utilization of iterated sigma point Kalman filter （ISPKF）, which minimizes statistical linearization error through Gaussian-Newton iteration, to design an optimal proposal distribution of the particle filter and to estimate the environment landmarks. On the basis of Rao-Blackwellized particle filter, the proposed ISP-FastSLAM algorithm is comprised by two main parts： in the first part, an iterated sigma point particle filter （ISPPF） to localize the robot is proposed, in which the proposal distribution is accurately estimated by the ISPKF; in the second part, a set of ISPKFs is used to estimate the environment landmarks. The simulation test of the proposed ISP-FastSLAM algorithm compared with FastSLAM2.0 algorithm and Unscented FastSLAM algorithm is carried out, and the performances of the three algorithms are compared. The simulation and comparing results show that the proposed ISP-FastSLAM outperforms other two algorithms both in accuracy and in robustness. The proposed algorithm provides reference for the optimization research of FastSLAM algorithm.

关键词： mobile robot simultaneous localization and mapping (SLAM) particle filter Kalman filter unscented transformation

Gradient estimates and coupling property for semilinear SDEs driven by jump processes

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Science China Mathematics 2015年第2期58卷 447-458页

作者： song yu Lin School of Mathematical Sciences Beijing Normal University

Let L be a L′evy process with characteristic measureν,which has an absolutely continuous lower bound *** Lebesgue measure on *** using Malliavin calculus for jump processes,we investigate Bismut formula,gradient est... 详细信息

关键词： jump processes Bismut formula gradient estimates coupling property

Studies on the Interaction of Cobalt Mixed-Ligand Coordination Compound Containing Tetrapyrido [3,2-a:2′,3′-c:3″, 2″-h:2■,3■-j] phenazine with DNA

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Chemical Research in Chinese Universities 2001年第3期17卷 243-248页

作者： song yu-fei YANG Pin Institute of Molecular Science Shanxi UniversityTaiyuan 030006P.R.China

A new monometallic complex [Co(phen)_2tpphz]^(3+) (where tpphz is tetrapyrido [3,2-a:2′,3′-c:3″,2″-h:2′″,3′″-j] phenazine) was synthesized by the reaction of 5, 6-diamino-1,10-phenanthroline with [Co(phen)_2(phendione)]^(3+). It was characterized by elemental analysis, molar conductivity, IR, ~1H NMR, ultraviolet and fluorescence spectroscopy. The interaction of the complex with DNA was also investigated. The complex shows the absorption hypochromicity, fluorescence enhancement, the specific viscosity increased when bound to calf thymus DNA. The cyclic voltammetry (CV) measurement showed a change in peak current with the addition of DNA. All the results provide the support for the intercalative binding mode of the mononuclear complex.

关键词： Tetrapyrido [3,2-a: 2′,3′-c: 3″,2″h, 2~■,3~■-j] phenazine Cobalt Calf thymus DNA Intercalative Binding mode

Time-dependent safety of lining structures of circular tunnels in weak rock strata

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International Journal of Mining Science and Technology 2022年第2期32卷 323-334页

作者： Baoguo Liu yu song Zhaofei Chu School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China School of Civil Engineering Wuhan UniversityWuhan 430072China

Following tunnel excavation and lining completion,fractured surrounding rock deforms gradually over time;this results in a time-dependent evolution of the pressure applied to the lining structure by the surrounding ***,the safety of the tunnel lining in weak strata is strongly correlated with *** this study,we developed an analytical method for determining the time-dependent pressure in the surrounding rock and lining structure of a circular tunnel under a hydrostatic stress *** the proposed method,the stress–strain relationship of the fractured surrounding rock is assumed to conform to that of the Burgers viscoelastic component,and the lining structure is assumed to be an *** on these assumptions,the viscoelastic deformation of the surrounding rock,the elastic deformation of the lining structure,and the coordinated deformation between the surrounding rock and lining structure were *** proposed analytical method,which employs a time-dependent safety coefficient,was subsequently used to estimate the durability of the lining structure of the Foling Tunnel in *** derived attenuation curve of the safety coefficient with respect to time can assist engineers in predicting the remaining viable life of the lining *** existing analytical methods,the method derived in this study considers the time dependency of the interaction between the surrounding rock and tunnel lining;hence,it is more suitable for the evaluation of lining lifetime.

关键词： Tunnel lining Surrounding rock pressure Rheological characteristics Weak rock strata Time-dependent safety

Research on PM_(2.5) Concentration Prediction Algorithm Based on Temporal and Spatial Features

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Computers, Materials & Continua 2023年第6期75卷 5555-5571页

作者： song yu Chen Wang School of Computer Science and Engineering Central South UniversityChangsha410000China

PM2.5 has a non-negligible impact on visibility and air quality as an important component of haze and can affect cloud formation and rainfall and thus change the climate,and it is an evaluation indicator of air pollution *** PM2.5 concentration prediction based on relevant historical data mining can effectively improve air pollution forecasting ability and guide air pollution prevention and *** past methods neglected the impact caused by PM2.5 flow between cities when analyzing the impact of inter-city PM2.5 concentrations,making it difficult to further improve the prediction ***,factors including geographical information such as altitude and distance and meteorological information such as wind speed and wind direction affect the flow of PM2.5 between cities,leading to the change of PM2.5 concentration in *** a PM2.5 directed flow graph is constructed in this *** and meteorological data is introduced into the graph structure to simulate the spatial PM2.5 flow transmission relationship between *** introduction of meteorological factors like wind direction depicts the unequal flow relationship of PM2.5 between *** on this,a PM2.5 concentration prediction method integrating spatial-temporal factors is proposed in this paper.A spatial feature extraction method based on weight aggregation graph attention network(WGAT)is proposed to extract the spatial correlation features of PM2.5 in the flow graph,and a multi-step PM2.5 prediction method based on attention gate control loop unit(AGRU)is *** PM2.5 concentration prediction model WGAT-AGRU with fused spatiotemporal features is constructed by combining the two methods to achieve multi-step PM2.5 concentration ***,accuracy and validity experiments are conducted on the KnowAir dataset,and the results show that the WGAT-AGRU model proposed in the paper has good performance in terms of prediction accuracy and validates the effectiveness

关键词： Spatiotemporal fusion PM2.5 concentration prediction graph neural network recurrent neural network attention mechanism

ESO-based robust predictive control of lunar module with fuel sloshing dynamics

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Journal of Central South University 2017年第3期24卷 589-598页

作者： song Zheng-yu College of Electrical Engineering Zhejiang UniversityHangzhou 310058China Beijing Aerospace Automatic Control Institute(BAACI) Beijing 100854China School of Aeronautics and Astronautics Central South UniversityChangsha 410083China

An extended-state-observer(ESO) based predictive control scheme is proposed for the autopilot of lunar *** slosh fuel masses exert forces and torques on the rigid body of lunar module(LM),such disturbances will dramatically undermine the stability of autopilot *** fuel sloshing dynamics and uncertainties due to the time-varying parameters are considered as a generalized disturbance which is estimated by an ESO from the measured attitude signals and the control input *** a continuous-time predictive controller driven by the estimated states and disturbances is designed to obtain the virtual control input,which is allocated to the real control actuators according to a deadband *** 6-DOF simulation results reveal the effectiveness of the proposed method when dealing with the fuel sloshing dynamics and parameter perturbations.

关键词： extended state observer predictive controller parameter perturbation fuel sloshing lunar module

Size distribution of inclusions in 12%Cr stainless steel with a wide range of solidification cooling rates

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International Journal of Minerals,Metallurgy and Materials 2015年第11期22卷 1157-1162页

作者： Han-song yu Jian-guo Li School of Materials Science and Engineering Shanghai Jiao Tong University

The effect of solidification cooling rate on the size and distribution of inclusions in 12%Cr stainless steel was investigated. A wide range of solidification cooling rates（from 0.05 to 106 K·s^-1） was achieved using various solidification processes, including conventional casting, laser remelting, and melt spinning. The size and distribution of inclusions in the steel were observed and statistically collected. For comparison, mathematical models were used to calculate the sizes of inclusions at different solidification cooling rates. Both the statistical size determined from observations and that predicted from calculations tended to decrease with increasing cooling rate; however, the experimental and calculated results did not agree well with each other at excessively high or low cooling rate. The reasons for this discrepancy were theoretically analyzed. For the size distribution of inclusions, the effect of cooling rate on the number densities of large-sized（〉 2 μm） inclusions and small-sized（≤ 2 μm） inclusions were distinct. The number density of inclusions larger than 1 μm was not affected when the cooing rate was less than or equal to 6 K·s^-1 because inclusion precipitation was suppressed by the increased cooling rate.

关键词： solidification cooling rate inclusions size distribution number density stainless steels

An economic assessment of the health effects and crop yield losses caused by air pollution in China's Mainland

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Journal of Environmental Sciences 2017年第6期29卷 102-113页

作者： Weijie Miao Xin Huang yu song State Key Joint Laboratory of Environmental Simulation and Pollution Control Department of Environmental SciencePeking University Belting 100871China Institute for Climate and Global Change Research School of Atmospheric SciencesNanjing UniversityNanfing 210093China

Air pollution is severe in China, and pollutants such as PM2.5 and surface 03 may cause major damage to human health and crops, respectively. Few studies have considered the health effects of PM2.5 or the loss of crop yields due to surface 03 using model-simulated air pollution data in China. We used gridded outputs from the WRF-Chem model, high resolution population data, and crop yield data to evaluate the effects on human health and crop yield in China's Mainland. Our results showed that outdoor PM2.5 pollution was responsible for 1.70-1.99 million cases of all-cause mortality in 2006. The economic costs of these health effects were estimated to be 151.1-176.9 billion USD, of which 90% were attributed to mortality. The estimated crop yield losses for wheat, rice, maize, and soybean were approximately 9, 4.6, 0.44, and 0.34 million tons, respectively, resulting in economic losses of 3.4 billion USD. The total economic losses due to ambient air pollution were estimated to be 154.5-180.3 billion USD, accounting for approximately 5.7%-6.6% of the total GDP of China in 2006. Our results show that both population health and staple crop yields in China have been significantly affected by exposure to air pollution. Measures should be taken to reduce emissions, improve air quality, and mitigate the economic loss.

关键词： PM2.5 Surface O3 Population healthCrop yield lossIntegrated assessmentEconomic lossChina's Mainland

基于“微生物-肠-脑轴”探讨补肾通腑方对APP/PS1小鼠肠道菌群及LPS/TLR4/NF-κB通路的影响

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中国药理学通报 2025年第1期41卷 171-178页

作者：王旭张杰赵敏宋晓雨段建平河南中医药大学第一附属医院脑病科河南郑州450000 河南中医药大学第一临床医学院河南郑州450000 中西医防治重大疾病河南省协同创新中心河南郑州450046

目的探讨补肾通腑方调控肠道菌群,改善阿尔茨海默病(Alzheimer’s disease,AD)模型小鼠学习记忆能力的作用机制。方法以APP/PS1小鼠为研究对象,给予补肾通腑方治疗8周,采用Morris水迷宫法观察小鼠空间学习记忆能力变化;16S rDNA检测小... 详细信息

目的探讨补肾通腑方调控肠道菌群,改善阿尔茨海默病(Alzheimer’s disease,AD)模型小鼠学习记忆能力的作用机制。方法以APP/PS1小鼠为研究对象,给予补肾通腑方治疗8周,采用Morris水迷宫法观察小鼠空间学习记忆能力变化;16S rDNA检测小鼠肠道菌群丰度、多样性变化;HE染色观察海马病理形态学变化;免疫荧光检测海马区小胶质细胞活化情况;Western blot检测TLR4、NF-κB、IL-6等炎症因子表达。结果与模型组相比,补肾通腑方可以缩短AD模型小鼠逃避潜伏期、游泳路径,增加跨越平台次数(P<0.05),提升肠道菌群多样性,调节肠道菌群丰度,促进海马神经元细胞损伤修复,降低iNOS/Iba1共表达,提高Arg1/Iba1共表达(P<0.01),促进小胶质细胞从M1型向M2型转化,下调TLR4、NF-κB、IL-6等促炎因子的表达。结论补肾通腑方改善AD模型小鼠学习记忆能力的作用机制可能与调节肠道菌群介导的LPS/TLR4/NF-κB通路,从而抑制促炎型小胶质细胞活化、减轻中枢神经系统炎症、改善海马区神经元细胞损伤有关。

关键词：阿尔茨海默病补肾通腑方肠道菌群 LPS/TLR4/NF-κB通路 16S rDNA 微生物-肠-脑轴