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Three-Rigid-Body-Particle Modeling and Optimization of Trajectory and Posture for Alpine Skiing

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Journal of Systems Science & Complexity 2024年第2期37卷 581-608页

作者： zhang Yijia FEI Qing YAO Xiaolan SUN jian zhang Yanjun CHEN Zhen School of Automation Beijing Institute of TechnologyBeijing 100081China

This paper presents a new study on modeling and optimization of trajectory and posture for the super-giant(SG)slalom of alpine *** is the first time that a Three-Rigid-Body-Particle model based on rigorous derivations and stability analysis is established to represent skiers trajectory and posture characteristics,as it is more accurate than the single-rigid-body model which is commonly used in existing *** addition,the Radau pseudospectral method is applied to solve the trajectory and posture optimization problem in order to obtain better skiing trajectory,skiing posture,and some key kinematic parameters of ***,this paper analyzes the effects of different body types,minimum turning radii,and flexor and extensor strength of knees and hip joint on skiing ***,based on the findings of the study,some advice about how to improve the performance of the SG slalom in view of science and technology is given to skiers and coaches for reference.

关键词： Alpine skiing modeling posture optimization Three-Rigid-Body-Particle model trajectory optimization

Searching for the Highest Energy of Pulsation and Critical Luminosity of Swift J0243.6+6124 Observed by Insight-HXMT

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Research in Astronomy and Astrophysics 2024年第5期24卷 61-69页

作者： Qing-Xia Zhao Xian Hou Ming-Yu Ge Shuang-nan zhang Yun-Xiang Xiao You-Li Tuo Zi-Xu Yang Ling-Da Kong Jin-Lu Qu Shu zhang jian-Cheng Wang Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences ChineseAcademy of SciencesBeijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Institut fur Astronomic und Astrophysik Sand 1D-72076 TabingenGemany School of Physics and Optoelectronic Engineering Shandong University of TechnologyZibo 255000China

Owing to the broad energy coverage of Insight-HXMT in the hard X-ray band,we detected the highest energy of pulsation exceeding 200 keV around the 2017–2018 outburst peak of the first Galactic pulsating ultraluminous X-ray source (PULX) Swift J0243.6+6124,which is the highest energy detected from PULXs to *** also obtained the highest energy of pulsation of every exposure during the outburst in 2017–2018,and found the highest energy is roughly positively correlated with *** our newly developed method,we identified the critical luminosity being 4×10^(38)erg s^(-1) when the main peaks of the low and high energy pulse profiles became aligned,which separates the fan-beam dominated and pencil-beam dominated accretion *** the critical luminosity,the phase of the main peak shifted gradually from 0.5 to 0.8 until the outburst peak in al energy bands is reached,which is in agreement with the phase shift found previously at low *** result is consistent with what is derived from spectral analysis.

关键词： (stars:)pulsars-individual(Swift J0243.6+6124)-X-rays binaries–stars neutron

Data-Driven Active Disturbance Rejection Control of Plant-Protection Unmanned Ground Vehicle Prototype: A Fuzzy Indirect Iterative Learning Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1892-1894页

作者： Tao Chen Ruiyuan Zhao jian Chen Zichao zhang College of Engineering China Agricultural UniversityBeijing 100083China Key Laboratory of Smart Agricultural Technology in Tropical South China Ministry of Agriculture and Rural AffairsGuangzhou 510642China

Dear Editor,This letter proposes a fuzzy indirect iterative learning(FIIL)active disturbance rejection control(ADRC)scheme to address the impact of uncertain factors of plant-protection unmanned ground vehicle(UGV),in which ADRC is a data-driven model-free control algorithm that only relies on the input and output data of the *** on the established nonlinear time-varying dynamic model including dynamic load(medicine box),the FIIL technology is adopted to turn the bandwidth and control channel gain online,in which the fuzzy logic system is used to update the gain parameters of iterative learning in real *** and experiment show the FIIL-ADRC scheme has better control performance.

关键词： Active scheme iterative

A sample of galaxy pairs identified from the LAMOST spectral survey and the Sloan Digital Sky Survey

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Research in Astronomy and Astrophysics 2016年第3期16卷 63-72页

作者： Shi-Yin Shen Maria Argudo-Femandez Li Chen Xiao-Yan Chen Shuai Feng Jin-Liang Hou Yong-Hui Hou Peng jiang Yi-Peng Jing Xu Kong A-Li Luo Zhi-jian Luo Zheng-Yi Shao Ting-Gui Wang Wen-Ting Wang Yue-Fei Wang Hong Wu Xue-Bing Wu Hai-Feng Yang Ming Yang Fang-Ting Yuan Hai-Long Yuan Hao-Tong zhang jian-nan zhang Yong zhang Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China Key Lab for Astrophysics Shanghai 200234China National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China University of Chinese Academy of Sciences Beijing 100049China nanjing Institute of Astronomical Optics&Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing 210042China University of Science and Technology of China Hefei 230026China Department of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Institute for Computational Cosmology University of DurhamSouth RoadDurhamDH1 3LEUK Department of Astronomy Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

A small fraction （〈 10%） of the SDSS main galaxy （MG） sample has not been targeted with spectroscopy due to the effect of fiber collisions. These galaxies have been compiled into the input catalog of the LAMOST ExtraGAlactic Surveys and named the complementary galaxy sample. In this paper, we introduce this project and status of the spectroscopies associated with the complementary galaxies in the first two years of the LAMOST spectral survey （till Sep. of 2014）. Moreover, we present a sample of 1102 galaxy pairs identified from the LAMOST complementary galaxies and SDSS MGs, which are defined as two members that have a projected distance smaller than 100 h^-01kpc and a recessional velocity difference smaller than 500 km s-1. Compared with galaxy pairs that are only selected from SDSS, the LAMOST- SDSS pairs have the advantages of not being biased toward large separations and therefore act as a useful supplement in statistical studies of galaxy interaction and galaxy merging.

关键词： galaxies: interactions -- galaxies: groups: general

Accurate simulations of pure-viscoacoustic wave propagation in tilted transversely isotropic media

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Petroleum Science 2024年第2期21卷 866-884页

作者： Qiang Mao jian-Ping Huang Xin-Ru Mu Ji-Dong Yang Yu-jian zhang Geosciences Department China University of Petroleum(East China)Qingdao266580ShandongChina Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266207ShandongChina

Forward modeling of seismic wave propagation is crucial for the realization of reverse time migration(RTM) and full waveform inversion(FWI) in attenuating transversely isotropic media. To describe the attenuation and anisotropy properties of subsurface media, the pure-viscoacoustic anisotropic wave equations are established for wavefield simulations, because they can provide clear and stable wavefields. However, due to the use of several approximations in deriving the wave equation and the introduction of a fractional Laplacian approximation in solving the derived equation, the wavefields simulated by the previous pure-viscoacoustic tilted transversely isotropic(TTI) wave equations has low accuracy. To accurately simulate wavefields in media with velocity anisotropy and attenuation anisotropy, we first derive a new pure-viscoacoustic TTI wave equation from the exact complex-valued dispersion formula in viscoelastic vertical transversely isotropic(VTI) media. Then, we present the hybrid finite-difference and low-rank decomposition(HFDLRD) method to accurately solve our proposed pure-viscoacoustic TTI wave equation. Theoretical analysis and numerical examples suggest that our pure-viscoacoustic TTI wave equation has higher accuracy than previous pure-viscoacoustic TTI wave equations in describing q P-wave kinematic and attenuation characteristics. Additionally, the numerical experiment in a simple two-layer model shows that the HFDLRD technique outperforms the hybrid finite-difference and pseudo-spectral(HFDPS) method in terms of accuracy of wavefield modeling.

关键词： Pure-viscoacoustic TTI wave equation Attenuation anisotropy Seismic modeling Low-rank decomposition method

Use of evergreen and deciduous plants by nocturnal-roosting birds:A case study in Beijing

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Avian Research 2024年第2期15卷 211-218页

作者： Yexi Zhao Jiayu zhang Zihan Li Qinmijia Xie Xin Deng Chenxi zhang nan Wang School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing 100083China

With continually increasing urbanization,the land cover in urban areas continues to change,resulting in the loss of *** are highly sensitive to changes in *** forest birds perch on plants that provide increased safety to reduce the risk of predation,and small birds may also consider insulation when using roosting plants in winter because of cold *** plants thus shape the nocturnal roosting environment of urban birds,and proper planting is essential for the survival of birds at *** use of roosting plants by urban birds should therefore be studied to provide a reference for *** the current study,we observed 1865 nocturnal roosting birds in Beijing from 2021 to 2022,with 23 species of birds from 12 families and 45 species of plants from 22 families *** chinensis exhibited the highest bird rarity-weighted richness,followed by Fraxinus pennsylvanica,Phyllostachys propinqua,Pinus tabuliformis,and Ulmus *** diameter at breast height,tree height,and crown width of plants used by birds was largest in summer and smallest in winter,and the perch height of birds was the highest in spring and summer and the lowest in *** used the highest proportion of deciduous plants in summer and the highest proportion of evergreen plants in winter.A significant seasonal difference in the use of evergreen and deciduous plants by small birds was noted,with a preference for deciduous plants in summer and evergreen plants in winter,while this preference was not found in large *** findings indicate that evergreen plants provide a vital nocturnal roosting environment for small birds in *** provide a better nocturnal roosting habitat for urban birds,we recommend paying attention to the combination of evergreen and deciduous plants when carrying out landscape construction.

关键词： Nocturnal roosting Roosting plant Seasonal variation Urban bird

Hemorrhagic cystitis in gastric cancer after nanoparticle albuminbound paclitaxel:A case report

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 1084-1090页

作者： Xin-Jie zhang jian Lou Department of Cancer Center The Fifth Affiliated Hospital of Wenzhou Medical UniversityLishui 323000Zhejiang ProvinceChina

BACKGROUND The advanced first-line regimen for advanced gastric cancer is based on a combination of fluoropyrimidine and platinum and/or paclitaxel(PTX),forming a two-or three-drug *** to conventional PTX,nanoparticle albumin-bound PTX(Nab-PTX)has better therapeutic effects and fewer adverse effects reported in ***-PTX is a great option for patients presenting with advanced gastric ***,we highlight an adverse event(hemorrhagic cystitis)of Nab-PTX in advanced gastric *** SUMMARY A 55-year-old male was diagnosed with lymph node metastasis after a laparo-scopic-assisted radical gastrectomy for gastric cancer that was treated by Nab-PTX and S-1(AS).On the 15th day after treatment with AS,he was diagnosed with hemorrhagic *** Physicians should be aware that hemorrhagic cystitis is a potential adverse event associated with Nab-PTX treatment.

关键词： nanoparticle albumin-bound paclitaxel Hemorrhagic cystitis Gastric cancer Adverse event Case report

Cobalt-based heterogeneous catalysts for photocatalytic carbon dioxide reduction

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Tungsten 2024年第2期6卷 410-421页

作者： Hong Yuan jian-Hua Mei Yun-nan Gong Di-Chang Zhong Tong-Bu Lu MOE International Joint Laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China

Solar light-driven CO_(2)reduction to high value-added chemicals has considered as an outstanding way to solve energy crisis and climate ***,various photocatalysts have been developed to achieve this *** them,cobaltbased heterogeneous catalysts have attracted great interest because of their promising performance,product selectivity and ***,we systematically summarize the research progress of various cobalt-based heterogeneous catalysts for the photoreduction of CO_(2),such as single-atom cobalt,and cobalt-based oxides,nitrides,sulfi des,phosphides,metal-organic frameworks and covalent-organic ***,the advantages and structure-activity relationship of these catalysts in photocatalytic CO_(2)reduction reaction are ***,the challenges and prospects for constructing cobaltbased heterogeneous catalysts with high effi ciency are highlighted.

关键词： Cobalt Heterogeneous catalysts CO_(2)reduction Photocatalysis

Blockchain-Based Certificateless Cross-Domain Authentication Scheme in the Industrial Internet of Things

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Computers, Materials & Continua 2024年第9期80卷 3835-3854页

作者： Zhaobin Li Xiantao Liu nan zhang Zhanzhen Wei Department of Electronic and Communication Engineering Beijing Electronic Science and Technology InstituteBeijing100070China

The Industrial Internet of Things(IIoT)consists of massive devices in different management domains,and the lack of trust among cross-domain entities leads to risks of data security and privacy leakage during information *** address the above challenges,a viable solution that combines Certificateless Public Key Cryptography(CL-PKC)with blockchain technology can be ***,as many existing schemes rely on a single Key Generation Center(KGC),they are prone to problems such as single points of failure and high computational *** this case,this paper proposes a novel blockchain-based certificateless cross-domain authentication scheme,that integrates the threshold secret sharing mechanism without a trusted center,meanwhile,adopts blockchain technology to enable cross-domain entities to authenticate with each other and to negotiate session keys *** scheme also supports the dynamic joining and removing of multiple KGCs,ensuring secure and efficient cross-domain authentication and key *** analysiswith other protocols demonstrates that the proposed cross-domain authentication protocol can achieve high security with relatively lowcomputational ***,this paper evaluates the scheme based on Hyperledger Fabric blockchain environment and simulates the performance of the certificateless scheme under different threshold parameters,and the simulation results show that the scheme has high performance.

关键词： IIoT blockchain certificateless cross-domain authentication