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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

Elevated CO_2 changes the moderate shade tolerance of yellow birch seedlings

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Journal of Environmental sciences 2007年第4期19卷 502-507页

作者： CHENG song Department of Biology Concordia University 7141 Sherbrooke Street West Montreal Quebec H4B 1R6 Canada Wuhan Botanical Garden Chinese Academy of Sciences Wuhan 430074 China.

To demonstrate the existence of light thresholds in plant growth and to examine the effects of elevated CO2 on the shade tolerance of a tree species, an experiment consisting of a completely randomized design for a total of 96 yellow birch （Betula alleghaniensis Britton） seedlings was conducted with 3 light levels （2.9%, 7.7%, 26.1% of full sunlight） × 2 CO2 levels （350 and 700±10 ppm） with 4 replications in a phytotron. The study proved that thresholds exist and they vary in different plant organs. In ambient CO2, the thresholds were 13.3%, 18.7%, 15.0%, 15.2%, and 15.6% of full sunlight for stem, leaf, root, total plant biomass, and the averaged value, respectively. In 700 ppm CO2, the corresponding thresholds were 16.7%, 21.3%, 18.1%, 21.7% and 19.5% for stem, leaf, root, total plant biomass, and the averaged value, respectively. The lowest threshold in the stem is an indicator of the minimal light intensity for regular growth for seedlings of this species. Below this threshold, light-stressful growth occurs. The result of a paired t-test indicated that the thresholds in elevated CO2 were significantly higher than in ambient CO2. This suggests that yellow birch will lose its moderate shade tolerance, evolutionally becoming a shade-intolerant species, and that it may become more difficult to naturally regenerate in the future.

关键词： elevated CO2 light threshold phytotron plant biomass yellow birch

Morphological structure and peripheral innervation of the lateral line system in the Siberian sturgeon (Acipenser baerii)

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Integrative Zoology 2012年第1期7卷 83-93页

作者： Wei song Jiakun song Institute for Marine Biosystem and Neuroscience Shanghai Ocean UniversityShanghaiChina

Light and scanning electron microscopy(SEM)were used to study the epidermal lateral line system of the Si-berian sturgeon(Acipenser baerii Brandt,1869).This system consists of mechanoreceptive neuromasts,ampul-lae and the electroreceptive *** neuromasts are located in 5 pairs of cephalic and 1 pair of trunk canals and superficially in the middle and posterior pit lines that lie dorsomedially along the top of the skull immedi-ately adjacent to the otic ampullae *** canal neuromasts and pit organ superficial neuromasts have oppo-site polarized hair cells that are parallel along the axis of the canal and pit line,***,they dif-fer in both size and shape and in the density and length of the hair *** ampullae are confined on the head,adjacent to the neuromast *** morphological structure of the ampullae in the Siberian sturgeon is similar to the ampullae in elasmobranchs and other primitive ***,it has a relatively large mucus-filled ampulla,and a shorter and narrower canal leading to a small opening to the outer epidermal *** also present new information concerning the peripheral innervation of lateral line receptors in *** re-ceptors of the lateral line system are innervated by 2 pairs of cranial nerves:anterior and posterior lateral line *** peripheral processes of the anterior lateral line nerve form superficial ophthalmic,buccal,otic and anteroventral *** peripheral processes of the posterior lateral line nerve form middle,supratemporal and lateral rami.

关键词： canal neuromasts electroreceptors lateral line nerves mechanoreceptors pit organ superficial neuromasts sturgeon

Evaluation of Coronal and Interplanetary Magnetic Field Extrapolation Using PSP Solar Wind Observation

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Research in Astronomy and Astrophysics 2023年第7期23卷 247-262页

作者： Yue-Chun song Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China school of Astronomy and Space science University of Science and Technology of ChinaHefei 230026China

Using solar wind observation near PSP perihelions as constraints,we have investigated the parameters in various PFSS model *** is found that the interplanetary magnetic field extrapolation with source surface height R_(SS)=2 Rs is better than that with R_(SS)=2.5 *** and GONG magnetograms show similar performances in the simulation of magnetic field variation,but the former appears to have a slight advantage in reconstruction of intensity while the latter is more adaptable to sparser *** finite-difference method of constructing eigenvalue problems for potential fields can achieve similar accuracy as the analytic method and greatly improve the computational *** modeling performs relatively less well in magnetic field prediction,but it is able to provide rich information about solar-terrestrial space.

关键词： magnetohydrodynamics(MHD) (Sun:)solar—terrestrial relations (Sun:)solar wind magnetic fields

Applying bases for "double control" artificial breeding of giant panda in captivity

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Chinese science Bulletin 1997年第9期42卷 775-779页

作者： Chen, DY song, XF Duan, CW Li, MW Sun, QY Liu, H Zhang, AJ Ye, ZY Li, sc Li, GH Yu, JQ Zhang, FX Feng, WH Zhong, SL He, GX song, YF Fei, LS State Key Laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing China Chengdu Bureau of Gardening Chengdu Research Base of Giant Panda Breeding Chengdu China Chengdu Zoo Chengdu China

THE giant panda is a kind of endangered rare animal,the number of which is less than onethousand at present,specially distributed in *** to the protective scheme issuedby The International Association of Nature Protec... 详细信息

关键词： giant panda hormone-induced oestrus ovulation sperm viability artificial insemination pregnancy protection.

Deciphering the molecular mechanisms of Simiaowan in the treatment of hyperuricemia: in vivo and in silico approaches

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Traditional Medicine Research 2025年第2期10卷 37-54页

作者： Yong-Chang Zeng Jun-Hong Wu Dan-Dan Xu Kang He Chang-Qing Liu Li-Fei song Zheng-Zhi Wu Qian-Qian Jiang Shao-Yu Liang Department of Neurology The First Affiliated Hospital of Shenzhen UniversityShenzhen 518020China Pharmaceutical Department The Affiliated TCM Hospital of Guangzhou Medical UniversityGuangzhou 510000China school of Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China Guangzhou Zeli Medical Technology Co. Ltd.Guangzhou 510700China

Background:Simiaowan(SMW),a well-known traditional Chinese medicine,has been employed to treat hyperuricemia(HUA)and gout for ***,the bioactive components and underlying mechanisms have not been *** objective of this study was to identify the active components and potential mechanisms of SMW by integrating pharmacological experimentation,serum pharmacochemistry,network pharmacology and molecular ***:HUA rats modelling by high-fat/high-sugar diet and potassium oxonate/adenine oral administration were used to evaluate the pharmacodynamic effects of ***-Q-Exactive-MS/MS was employed to detect the bioactive components present in SMW-containing *** pharmacology and molecular docking were utilized to elucidate the potential targets and underlying ***:SMW effectively ameliorated HUA rats via the inhibition of uric acid(UA)production,promotion of UA excretion,improvement of lipid and glucose metabolic abnormalities,antioxidant,anti-inflammatory and anti-insulin resistance effects.A total of 73 compounds detected in SMW-containing serum were identified as potential active components,with alkaloids,flavonoids,organic acids,and terpenoids emerging as the primary active *** 203 corresponding targets were obtained as SMW anti-HUA/gout targets,which mainly participated in apoptosis,insulin resistance,TNF,PI3K-Akt,HIF-1,NF-κB,MAPK,IL-17 and TLR signaling *** docking indicated that active compounds(***,phellodendrine,quercetin,formononetin,ferulic acid)had superior binding abilities to the key targets(*** carrier family 22 member 12(URAT1),solute carrier family 22 member 6(OAT1),ATP-binding cassette sub-family G member 2(ABCG2),solute carrier family 2,facilitated glucose transporter member 9(GLUT9),xanthine dehydrogenase/oxidase(XDH),transcription factor p65(RELA),toll-like receptor 4(TLR4),prostaglandin G/H synthase 2(PTGS2),caspase-3(CASP3),insulin(INS)).Conclusion:S

关键词： hyperuricemia network pharmacology serum pharmacochemistry Simiaowan UPLC-Q-Exactive-MS/MS

Amino acid assisted aqueous synthesis of highly stable CsPbBr_(3)nanocrystals for cell imaging

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Nano Research 2025年第1期18卷 675-683页

作者： Xue Li Yanan Guo Guoying Tan Qingyi Liu Nan song Yu Tang State Key Laboratory of Applied Organic Chemistry Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu ProvinceCollege of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030China

Lead halide perovskite nanocrystals(NCs)exhibit excellent optoelectronic performance and have drawn great interests in the fields of biological imaging and ***,the poor stability of CsPbX_(3)(X=Cl,Br,I)in water is still a challenge to hinder their practical *** this work,a facile strategy has been developed for aqueous synthesis of CsPbX_(3) nanocrystals,in which L-glutamic acid(LGlu)has been used to replace oleic acid in the synthetic *** from the synergic effects of L-Glu and oleylamine(OAm),CsPbBr_(3)nanocrystals(L-Glu/OAm-CsPbBr_(3)NCs)with high water stability have been directly prepared under a mild condition at room temperature in water,facilitated by the process of crystal phase transformation from Cs_(4)PbBr_(6) to CsPbBr_(3).L-Glu/OAm-CsPbBr_(3)NCs exhibit a high quantum yield of 85%and a narrow full width at half maximum of 16 nm,demonstrating their efficient luminescence in ***,L-Glu on the surface have contributed greatly to an acidic environment and passivation of surface defects,improving the water stability and dispersibility of CsPbBr_(3)***,L-Glu/OAm-CsPbBr_(3)NCs exhibit great biocompatibility due to the presence of L-Glu,resulting in their good performance for HeLa cell ***,we propose a facile and effective method to prepare CsPbBr_(3)nanocrystals with excellent water stability by using L-Glu and OAm as cooperated ligands and expand their application in cell imaging.

关键词： aqueous synthesis cell imaging lead halide perovskite nanocrystals L-glutamic acid phase transformation

Structural characterization of the{1122}twin boundary and the corresponding stress accommodation mechanisms in pure titanium

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Journal of Materials science & Technology 2021年第13期72卷 114-121页

作者： Bingqiang Wei song Ni Yong Liu Min song State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

{11-22}compression twin plays an important role in accommodating deformation along the c axis of HCP ***,the studies on the interface structure of{11-22}twin boundary(TB),especially the twin tip,and the corresponding local stress release mechanism are still *** work studied the interface characters of{11-22}TB of a deformed pure titanium by transmission electron ***{11-22}TB presented serrated character,consisting of coherent twin boundary(CTB)and(0002)_(T)//(11-2-2)_(M)or(11-2-2)_(T)//(0002)_(M)steps,and the twin tip was fully composed of the basal-pyramidal(BPy)and pyramidal-basal(PyB)*** twin tip presents asymmetric morphology and the step height at the twin tip is much larger than that away from the twin *** types of local stress accommodation mechanisms were observed:zonal dislocation emission and hexagonal close packed structure to facecentered cubic structure *** zonal dislocation was produced by the dissociation of the1/3dislocation that was nucleated at the twin tip and the phase transformation was introduced by emission of Shockley partial dislocations from the{11-22}twin boundary.

关键词： {1122} twin Twin boundary Twinning dislocation Stress accommodation Titanium

Aerodynamic performance of owl-like airfoil undergoing bio-inspired flapping kinematics

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Chinese Journal of Aeronautics 2021年第5期34卷 239-252页

作者： Xinyu LANG Bifeng song Wenqing YANG Wenping song school of Aeronautics Northwestern Poly technical UniversityXi'an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China Yangtze River Delta Research Institute of Northwestern Polytechnical University Taicang 215400China

Natural flyers have extraordinary flight skills and their prominent aerodynamic performance has attracted a lot of ***,the aerodynamic mechanism of birds’flapping wing kinematics still lacks in-depth *** this paper,the aerodynamic performance of owl-like airfoil undergoing bio-inspired flapping kinematics extracted from a free-flying owl wing has been numerically *** overset mesh technique is used to deal with the large range movements of flapping *** bio-inspired kinematics consist of plunging and pitching movement.A pure sinusoidal motion and a defined motion composed of plunging of sinusoidal motion and pitching of the bio-inspired kinematics are selected for *** other two NACA airfoils are also selected to figure out the advantages of the owl-like *** is found that the cambered owl-like airfoil can enhance lift during the *** bio-inspired kinematics have an obvious advantage in lift generation with a presence of higher peak lift and positive lift over a wider proportion of the flapping ***,the bio-inspired motion is more economical for a lower power consumption compared with the sinusoidal *** sinusoidal flapping motion is better for thrust generation for a higher peak thrust value in both upstroke and downstroke,while the bio-inspired kinematics mainly generate thrust during the downstroke but produce more drag during the *** defined motion has similar lift performance with the bio-inspired kinematics,while it consumes more energy and generates less *** unsteady flow field around airfoils is also analyzed to explain the corresponding *** research in this paper is helpful to understand the flight mechanism of birds and to design a micro air vehicle with higher performance.

关键词： Aerodynamic performance Bio-inspired kinematics Flapping airfoils Low Reynolds number Micro aerial vehicles