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Receding-Horizon Trajectory Planning for Under-Actuated Autonomous Vehicles Based on Collaborative Neurodynamic Optimization

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IEEE/CAA Journal of Automatica Sinica 2022年第11期9卷 1909-1923页

作者： Jiasen Wang Jun Wang Qing-Long Han IEEE the Future Network Research center Purple Mountain LaboratoriesNanjing 211111China the Department of Computer Science the School of Data ScienceCity University of Hong KongHong KongChina the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia

This paper addresses a major issue in planning the trajectories of under-actuated autonomous vehicles based on neurodynamic optimization.A receding-horizon vehicle trajectory planning task is formulated as a sequential global optimization problem with weighted quadratic navigation functions and obstacle avoidance constraints based on given vehicle goal configurations.The feasibility of the formulated optimization problem is guaranteed under derived conditions.The optimization problem is sequentially solved via collaborative neurodynamic optimization in a neurodynamics-driven trajectory planning method/procedure.Simulation results with under-actuated unmanned wheeled vehicles and autonomous surface vehicles are elaborated to substantiate the efficacy of the neurodynamics-driven trajectory planning method.

关键词： Collaborative neurodynamic optimization receding-horizon planning trajectory planning under-actuated vehicles

Exponential Convergence of Primal-Dual Dynamical System for Linear Constrained Optimization

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IEEE/CAA Journal of Automatica Sinica 2022年第4期9卷 745-748页

作者： Luyao Guo Xinli Shi Jinde Cao the School of Mathematics Southeast University IEEE School of Cyber Science&Engineering Southeast University School of Mathematics Frontiers Science Center for Mobile Information Communication and SecuritySoutheast University Purple mountain Laboratories Yonsei Frontier Laboratory Yonsei University

Dear editor,Primal-dual dynamics(PDD)and its variants are prominent first-order continuous-time algorithms to determine the primal and dual solutions of a constrained optimization problem(COP).Due to the simple structure,they have received widespread attention in various fields,such as distributed optimization[1],power systems[2],and wireless communication[3].In view of their wide applications,there are numerous theoretic studies on the convergence properties of PDD and its variants,including the exponential stability analysis[4]-[9].

关键词： Primal optimization Convergence

Using physiological conditions to assess current and future habitat use of a Subarctic frog

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Integrative Zoology 2023年第1期18卷 2-14页

作者： Thomas P.HASTINGS Blake R.HOSSACK LeeAnn FISHBACK Jon M.DAVENPORT Department of Biology Appalachian State UniversityBooneNorth CarolinaUSA U.S.Geological Survey Northern Rocky Mountain Science Centerand Wildlife Biology ProgramW.A.Franke College of Forestry&ConservationUniversity of MontanaMissoulaMontanaUSA Churchill Northern Studies Centre ChurchillManitobaCanada

Species with especially close dependence on the environment to meet physiological requirements,such as ectotherms,are highly susceptible to the impacts of climate change.Climate change is occurring rapidly in the Subarctic and Arctic,but there is limited knowledge on ectotherm physiology in these landscapes.We investigated how environmental conditions and habitat characteristics inﬂuence the physiological conditions and habitat use of wood frogs(Rana sylvatica)in a Subarctic landscape near Churchill,Manitoba(Canada).We used plaster models to estimate water loss rates and surface body temperatures among different habitat types and at speciﬁc locations used by radio-tracked frogs.Water loss(R2=0.67)and surface temperature(R2=0.80)of plaster models was similar to that of live frogs.Model-based water loss rates were greater in tundra habitat than in boreal forest and ecotone habitat.Habitat use of wood frogs was strongly tied with available surface moisture and decreased water loss rates that were observed with plaster models.Environmental conditions,such as wind speed and ground tem-perature,explained 58%and 91%of the variation in water balance and temperature of plaster models.Maintaining physiological conditions may be challenging for semi-aquatic ectotherms in environments vulnerable to future cli-mate change.The ability to predict physiological conditions based on environmental conditions,as demonstrated in our study,can help understand how wildlife will respond to climatic changes.

关键词： Arctic climate change landscape physiology water balance wood frog

The Crested Ibises expanding to plain areas exhibit a higher tolerance of human proximity

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Avian Research 2024年第1期15卷 60-65页

作者： Yuqi Zou Yiting Jiang Zitan Song Xiaobin Fang Changqing Ding School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing100083China Department of Biology University of KonstanzKonstanz78464Germany center for the Advanced Study of Collective Behavior University of KonstanzKonstanz78464Germany School of Life Sciences Liaoning UniversityShenyang110036China Comparative Socioecology Group Max Planck Institute for Animal BehaviorKonstanz78467Germany

Animals must strike a balance between anti-predation behavior and other essential behaviors,such as foraging.Within the same species,strategies may vary on individuals’risk-taking preferences,and in this process the environment is a determinant,in addition to predator regime.The Crested Ibis(Nipponia nippon)exhibits such tendency.This is an endangered species,once inhabiting exclusively in China’s Qinling mountain.This used to be the sole remaining wild population.However,over recent decades,this population has expanded.A portion has relocated to breed in the lower plain area,which is characterized by elevated level of human activities and landscape complexity.We used flight initiation distance(FID)as an indicator of the ibises’risk-taking preference,particularly their response to human proximity.Additionally,we examined the environmental factors influencing their foraging site selection,including altitude,terrain openness,human activity intensity and human construction.Our findings revealed a significantly shorter FID among individuals relocating to plain habitats,indicating a higher tolerance of human proximity.The results showed that FID decreased with distance to the nearest human settlement.Another finding is that FID was independent of instant human activity intensity and environmental factors(altitude and terrain openness).These different may arise from various combinations of human activity,predation risk,and food abundance within the two habitats.These results provide insights into the in situ conservation of the threatened species within the context of global urbanization.

关键词： Anti-predation behavior Flight initiation distance Habitat expansion Human activity Nipponia nippon

Performance of composite foundations with different load transfer platforms and substratum stiffness over silty clay

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Journal of mountain Science 2024年第5期21卷 1761-1774页

作者： ZHANG Shuming LIU Yan YUAN Shengyang LIU Xianfeng JIANG Guanlu LIU Junyan School of Civil Engineering and Architecture University of JinanJinan 250022China The Engineering Technology Research center for Urban Underground Engineering Supporting and Risk Monitoring of Shandong Province Jinan 250022China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of High-speed Railway Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China

The semi-rigid pile-supported composite foundation is widely used in highway projects due to its effectiveness in increasing the bearing capacity and stability of foundations.It is crucial to understand the stress distribution across the embankment width and the behaviour of unreinforced foundations.Thus,five centrifuge tests were conducted to examine the bearing and deformation behaviours of NPRS(Non-Connected Piled Raft Systems)and GRPS(GeosyntheticReinforced Pile-Supported systems)with varying substratum stiffness,then a comparative analysis was conducted on embankment settlement,pressures underneath the embankments,and axial forces along the piles.The results indicated that greater substratum stiffness correlates with reduced settlement and deformation at various depths.Deformation occurring 5 meters from the embankment toe includes settlement in NPRS and upward movement in GRPS.The potential sliding surface is primarily located within the embankment in NPRS,whereas it may extend through both the embankment and foundation in GRPS.The pile-soil stress ratio and efficiency in NPRS are higher than in GRPS across the embankment.The axial force borne by end-bearing piles is significantly greater than that by floating piles.As the buried depth increases,the axial force in GRPS initially rises then declines,whereas in NPRS,it remains relatively constant within a certain range before decreasing.This study aids in assessing the applicability of composite foundations in complex railway environments and provides a reference for procedural measures under similar conditions.

关键词： Centrifuge modelling Composite foundation Failure mode Load transfer platform Substratum Stiffness Silty clay

Potential and progress of studying mountain biodiversity by means of butterfly genetics and genomics

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Journal of Genetics and Genomics 2024年第3期51卷 292-301页

作者： Shuting Wang Marco Girardello Wei Zhang State Key Laboratory of Protein and Plant Gene Research School of Life SciencesPeking UniversityBeijing 100871China Peking-Tsinghua center for Life Sciences Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China cE3c-Centre for Ecology Evolution and Environmental Changes/Azorean Biodiversity GroupFaculdade de Ciencias Agrarias e do AmbienteUniversidade dos Açores9700-042 Angra do HeroísmoTerceiraPortugal

mountains are rich in biodiversity,and butterflies are species-rich and have a good ecological and evolutionary research foundation.This review addresses the potential and progress of studying mountain biodiversity using butterflies as a model.We discuss the uniqueness of mountain ecosystems,factors influencing the distribution of mountain butterflies,representative genetic and evolutionary models in butterfly research,and evolutionary studies of mountain biodiversity involving butterfly genetics and genomics.Finally,we demonstrate the necessity of studying mountain butterflies and propose future perspectives.This review provides insights for studying the biodiversity of mountain butterflies as well as a summary of research methods for reference.

关键词： mountain ecosystem Butterfly Biodiversity Adaptation Genomics Genetics

Pleistocene glaciation advances the cryptic speciation of Stellera chamaejasme L. in a major biodiversity hotspot

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Journal of Integrative Plant Biology 2024年第6期66卷 1192-1205页

作者： Santosh Kumar Rana Hum Kala Rana Jacob B.Landis Tianhui Kuang Juntong Chen Hengchang Wang Tao Deng Charles C.Davis Hang Sun CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences Arkansas Biosciences Institute Arkansas State University School of Integrative Plant Science Section of Plant Biology and the L.H.Bailey Hortorium Cornell University BTI Computational Biology center Boyce Thompson Institute CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Chinese Academy of Sciences Department of Organismic and Evolutionary Biology Herbaria Harvard University

The mountains of Southwest China comprise a significant large mountain range and biodiversity hotspot imperiled by global climate change. The high species diversity in this mountain system has long been attributed to a complex set of factors, and recent large-scale macroevolutionary investigations have placed a broad timeline on plant diversification that stretches from 10 million years ago(Mya) to the present. Despite our increasing understanding of the temporal mode of speciation, finer-scale populationlevel investigations are lacking to better refine these temporal trends and illuminate the abiotic and biotic influences of cryptic speciation. This is largely due to the dearth of organismal sampling among closely related species and populations, spanning the incredible size and topological heterogeneity of this region. Our study dives into these evolutionary dynamics of speciation using genomic and ecomorphological data of Stellera chamaejasme L. We identified four previously unrecognized cryptic species having indistinct morphological traits and large metapopulation of evolving lineages, suggesting a more recent diversification(～2.67–0.90 Mya), largely influenced by Pleistocene glaciation and biotic factors. These factors likely influenced allopatric speciation and advocated cyclical warming–cooling episodes along elevational gradients during the Pleistocene. The study refines the evolutionary timeline to be much younger than previously implicated and raises the concern that projected future warming may influence the alpine species diversity,necessitating increased conservation efforts.

关键词： cryptic speciation glacial-interglacial Hengduan mountains north-south migration Stellera chamaejasme

Structure-based design of novel heterocyclesubstituted ATDP analogs as non-nucleoside reverse transcriptase inhibitors with improved selectivity and solubility

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Acta Pharmaceutica Sinica B 2023年第12期13卷 4906-4917页

作者： Li-Min Zhao Christophe Pannecouque Erik De Clerc Shuai Wang Fen-Er Chen Key Laboratory of Natural Resources of Changbai mountain&Functional Molecules Ministry of EducationYanbian University College of PharmacyYanbian UniversityYanji 133002China Engineering center of Catalysis and Synthesis for Chiral Molecules Department of ChemistryFudan UniversityShanghai 200433China Shanghai Engineering center of Industrial Asymmetric Catalysis for Chiral Drugs Shanghai 200433China Rega Institute for Medical Research KU LeuvenLeuven B-3000Belgium

Following on our recently developed biphenyl-ATDP non-nucleoside reverse transcriptase inhibitor ZLM-66(SI=2019.80,S=1.9μg/mL),a series of novel heterocycle-substituted ATDP derivatives with significantly improved selectivity and solubility were identified by replacement of the biphenyl moiety of ZLM-66 with heterocyclic group with lower lipophilicity.Evidently,the representative analog 7w in this series exhibited dramatically enhanced selectivity and solubility(SI=12,497.73,S=4472μg/mL)in comparison with ZLM-66(SI=2019.80,S=1.9μg/mL).This new NNRTI conferred low nanomolar inhibition of wild-type HIV-1 strain and tested mutant strains(K103N,L1001,Y181C,E138K,and K103N+Y181C).The analog also demonstrated favorable safety and pharmacokinetic profiles,as evidenced by its insensitivity to CYP and hERG,lack of mortality and pathological damage,and good oral bioavailability in rats(F=27.1%).Further development of 7w for HIV therapy will be facilitated by this valuable information.

关键词： HIV-1 RT NNRTIS ATDP Pyridone

Growth and Interactions of Multi-Source Perturbations in Convection-Allowing Ensemble Forecasts

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Journal of Tropical Meteorology 2024年第2期30卷 118-131页

作者：张璐闵锦忠庄潇然王世璋魏莉青 Key Laboratory of Meteorological Disaster of Ministry of Education/Collaborative Innovation center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044 China Jiangsu Meteorological Observatory Jiangsu Meteorological ServiceNanjing 210008 China Nanjing Joint Institute for Atmospheric Sciences Nanjing 210000 China

This study investigated the growth of forecast errors stemming from initial conditions(ICs),lateral boundary conditions(LBCs),and model(MO)perturbations,as well as their interactions,by conducting seven 36 h convectionallowing ensemble forecast(CAEF)experiments.Two cases,one with strong-forcing(SF)and the other with weak-forcing(WF),occurred over the Yangtze-Huai River basin(YHRB)in East China,were selected to examine the sources of uncertainties associated with perturbation growth under varying forcing backgrounds and the influence of these backgrounds on growth.The perturbations exhibited distinct characteristics in terms of temporal evolution,spatial propagation,and vertical distribution under different forcing backgrounds,indicating a dependence between perturbation growth and forcing background.A comparison of the perturbation growth in different precipitation areas revealed that IC and LBC perturbations were significantly influenced by the location of precipitation in the SF case,while MO perturbations were more responsive to convection triggering and dominated in the WF case.The vertical distribution of perturbations showed that the sources of uncertainties and the performance of perturbations varied between SF and WF cases,with LBC perturbations displaying notable case dependence.Furthermore,the interactions between perturbations were considered by exploring the added values of different source perturbations.For the SF case,the added values of IC,LBC,and MO perturbations were reflected in different forecast periods and different source uncertainties,suggesting that the combination of multi-source perturbations can yield positive interactions.In the WF case,MO perturbations provided a more accurate estimation of uncertainties downstream of the Dabie mountain and need to be prioritized in the research on perturbation development.

关键词： convection-allowing ensemble forecast forcing background perturbation growth interactions added value