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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

Topologically Correct Intersection Curves of Two Trimmed Quadrics with Tolerance Control

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Journal of Systems Science & Complexity 2024年第5期37卷 2207-2239页

作者： SHAO Wenbing chen Falai Department of Mathematics University of Science and Technology of China

Surface/surface intersection is a fundamental problem in Compute Aided Design and Geometric Modeling since it is essential to solid modeling, numerically controlled machining, feature recognition, computer animation, etc. In practical applications, quadric surfaces, which are the most basic type of surfaces, are typically bounded surfaces trimmed by a sequence of planes. In this paper,a robust algorithm is proposed for computing the intersection curve segments of two trimmed quadrics based on the parametric representation of the intersection curves of two quadrics. The proposed algorithm guarantees correct topology and ensures that the approximation errors of the end points of the intersection curve segments are less than a given tolerance. The error control is based on an effective solution to a set of polynomial inequality system using the root isolation technique. Some examples are presented to validate the robustness and effectiveness of the proposed algorithm.

关键词： Polynomial inequality system root isolation surface/surface intersection tolerance control trimmed quadrics

Non-interactive SM2 threshold signature scheme with identifiable abort

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Frontiers of Computer Science 2024年第1期18卷 171-185页

作者： Huiqiang LIANG Jianhua chen School of Mathematics and Statistics Wuhan UniversityWuhan 430072China

A threshold signature is a special digital signature in which the N-signer share the private key x and can construct a valid signature for any subset of the included t-signer,but less than t-signer cannot obtain any *** the breakthrough achievements of threshold ECDSA signature and threshold Schnorr signature,the existing threshold SM2 signature is still limited to two parties or based on the honest majority setting,there is no more effective solution for the multiparty *** make the SM2 signature have more flexible application scenarios,promote the application of the SM2 signature scheme in the blockchain system and secure cryptocurrency *** paper designs a non-interactive threshold SM2signature schemebasedon partially homomorphic encryption and zero-knowledge *** the last round requires the message input,so make our scheme non-interactive,and the pre-signing process takes 2 rounds of communication to complete after the key *** allow arbitrary threshold t

关键词： SM2 signature secure multi-party computation threshold signature UC-secure dishonest majority

Mid-infrared Period-Luminosity Relations of Gaia DR3 Long Period Variables

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Research in Astronomy and Astrophysics 2024年第7期24卷 56-70页

作者： Xiaohan chen Xiaodian chen Licai Deng Shu Wang Tianlu chen Department of Physics College of ScienceTibet UniversityLhasa 850000China Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of the Chinese Academy of SciencesBeijing 100049China Department of Astronomy China West Normal UniversityNanchong 637009China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China

Long period variable(LPV)stars are very promising distance indicators in the infrared *** selected asymptotic giant branch(AGB)stars in the Large and Small Magellanic Cloud(LMC and SMC)from the Gaia Data Release 3 LPV catalog,and classified them into oxygen-rich(O-rich)and carbon-rich(C-rich)AGB *** the Wide-field Infrared Survey Explorer database,we determined the W1-and W2-band period-luminosity relations(PLRs)for each pulsation-mode sequence of AGB *** dispersion of the PLRs of O-rich AGB stars in sequences C'and C is relatively small,around 0.14 *** PLRs of LMC and SMC are consistent in each *** the W2 band,the PLR of large-amplitude C-rich AGB stars is steeper than that of small-amplitude C-rich AGB stars,due to their more circumstellar *** two methods,we find that some PLR sequences of O-rich AGB stars in the LMC are dependent on *** coefficients of the metallicity effect areβ=-0.533±0.213 mag dex~1andβ=-0.767±0.158 mag dex~1for sequence C in W1 and W2 bands,*** significance of the metallicity effect in W1 band for the four sequences is 2.2-3.5σ.Both of these imply that distance measurements using O-rich Mira may need to take the metallicity effect into account.

关键词： stars variables general-stars distances-infrared stars

Pathways toward a pollution-free planet and challenges

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 3-8页

作者： Jiuhui Qu Jiaping chen School of Environment Tsinghua UniversityBeijing 100084China College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

The mission of“Establishment of Zero-Pollution Earth”defined by United Nations Environment Programme aims at creation of a clean,safe and prosperous home for all human *** is of rational choice from each individual to protect our environment and demonstrates our great ambition to achieve our *** key message given in this article is that,zero pollution does not mean no discharge of pollutants and instead it can be achievable through optimizing and controlling a sound balance between pollutants discharge and capacities of decontamination through treatment and natural environmental accumulation,which can be termed as“Principle of Equilibrium”between pollution and *** on this principle,we propose and illustrate several key factors and synergistic pathways toward a pollution-free planet:quantitative determination on purification and wastewater;source control through green measures;minimization of negative side-effects;precise management through digitalized systems;and keeping sound balance between pollutants and natural *** should be noted that we would face a series of difficulties and challenges in moving forward to“Zero-Pollution Earth”.We should further develop theories,principles and tools to achieve the balance between quantity of pollutants and decontamination *** should work together to break through the bottleneck limited by“Principle of equilibrium”to establish new environmental remediation systems leading to“Zero-Pollution Earth”.

关键词： Wastewater treatment Resources Recovery Greenhouse gases Energy Pollution-free

Adaptive Space Expansion for Fast Motion Planning

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1499-1514页

作者： Shenglei Shi Jiankui chen State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The sampling process is very inefficient for sam-pling-based motion planning algorithms that excess random sam-ples are generated in the planning *** this paper,we pro-pose an adaptive space expansion(ASE)approach which belongs to the informed sampling category to improve the sampling effi-ciency for quickly finding a feasible *** ASE method enlarges the search space gradually and restrains the sampling process in a sequence of small hyper-ellipsoid ring subsets to avoid exploring the unnecessary ***,for a con-structed small hyper-ellipsoid ring subset,if the algorithm cannot find a feasible path in it,then the subset is ***,the ASE method successively does space exploring and space expan-sion until the final path has been ***,we present a particular construction method of the hyper-ellipsoid ring that uniform random samples can be directly generated in *** last,we present a feasible motion planner BiASE and an asymptoti-cally optimal motion planner BiASE*using the bidirectional exploring method and the ASE *** demon-strate that the computation speed is much faster than that of the state-of-the-art *** source codes are available at https://***/shshlei/ompl.

关键词： Adaptive space expansion(ASE) hyper-ellipsoid ring informed sampling motion planning.

UAV-assisted data collection for wireless sensor networks with dynamic working modes

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Digital Communications and Networks 2024年第3期10卷 805-812页

作者： Jie chen Jianhua Tang Shien-Ming Wu School of Intelligent Engineering South China University of TechnologyGuangzhou511442China

Wireless Sensor Network(WSN)is a cornerstone of Internet of Things(IoT)and has rich application *** this work,we consider a heterogeneous WSN whose sensor nodes have a diversity in their Residual Energy(RE).In this work,to protect the sensor nodes with low RE,we investigate dynamic working modes for sensor nodes which are determined by their RE and an introduced energy ***,we employ an Unmanned Aerial Vehicle(UAV)to collect the stored data from the heterogeneous *** aim to jointly optimize the cluster head selection,energy threshold and sensor nodes’working mode to minimize the weighted sum of energy con-sumption from the WSN and UAV,subject to the data collection rate *** this end,we propose an efficient search method to search for an optimal energy threshold,and develop a penalty-based successive convex approximation algorithm to select the cluster *** we present a low-complexity iterative approach to solve the joint optimization problem and discuss the implementation *** results justify that our proposed approach is able to reduce the energy consumption of the sensor nodes with low RE significantly and also saves energy for the whole WSN.

关键词： Unmanned aerial vehicle Wireless sensor networks Cluster heads Dynamic working modes

A proof system of the CaIT calculus

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Frontiers of Computer Science 2024年第2期18卷 123-137页

作者： Ningning chen Huibiao ZHU Shanghai Key Laboratory of Trustworthy Computing East China Normal UniversityShanghai 200062China

The Internet of Things(IoT)can realize the interconnection of people,machines,and things anytime,*** of the existing research mainly focuses on the practical applications of IoT,and there is a lack of research on modeling and reasoning about IoT systems from the perspective of formal ***,the Calculus of the Internet of Things(CaIT)has been proposed to specify and analyze IoT systems before the actual implementation,which can effectively improve development efficiency,and enhance system quality and *** verify the correctness of IoT systems described by CaIT,this paper presents a proof system for CaIT,in which specifications and verifications are based on the extended Hoare Logic with ***,we explore the cooperation between isolated proofs to validate the postconditions of the communication actions occurring in these proofs,with a particular focus on broadcast *** also demonstrate the soundness of our proof system.A simple“smart home”is given to illustrate the availability of our proof system.

关键词： Internet of Things(loT) Calculus of the Internet of Things(CalT) extended hoare logic cooperation smart home

Dominant woody plant species recognition with a hierarchical model based on multimodal geospatial data for subtropical forests

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Journal of Forestry Research 2024年第3期35卷 111-130页

作者： Xin chen Yujun Sun State Forestry&Grassland Administration Key Laboratory of Forest Resources&Environmental Management Beijing Forestry UniversityBeijing 100083People's Republic of China

Since the launch of the Google Earth Engine(GEE)cloud platform in 2010,it has been widely used,leading to a wealth of valuable ***,the potential of GEE for forest resource management has not been fully *** extract dominant woody plant species,GEE combined Sen-tinel-1(S1)and Sentinel-2(S2)data with the addition of the National Forest Resources Inventory(NFRI)and topographic data,resulting in a 10 m resolution multimodal geospatial dataset for subtropical forests in southeast *** and texture features,red-edge bands,and vegetation indices of S1 and S2 data were computed.A hierarchical model obtained information on forest distribution and area and the dominant woody plant *** results suggest that combining data sources from the S1 winter and S2 yearly ranges enhances accuracy in forest distribution and area extraction compared to using either data source ***,for dominant woody species recognition,using S1 winter and S2 data across all four seasons was *** terrain factors and removing spatial correlation from NFRI sample points further improved the recognition *** optimal forest extraction achieved an overall accuracy(OA)of 97.4%and a maplevel image classification efficacy(MICE)of 96.7%.OA and MICE were 83.6%and 80.7%for dominant species extraction,*** high accuracy and efficacy values indicate that the hierarchical recognition model based on multimodal remote sensing data performed extremely well for extracting information about dominant woody plant *** the results using the GEE application allows for an intuitive display of forest and species distribution,offering significant convenience for forest resource monitoring.

关键词： Google Earth Engine Sentinel Forest resource inventory data Dominant woody plant species Subtropics Model performance

Efficient Removal of Phosphate from Aqueous Solutions Using Corundum-hollow-spheres Supported Caclined Hydrotalcite Porous Thin Films

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 44-49页

作者：刘云才 ZHU chen School of Architecture and Materials Engineering Hubei Second Normal UniversityWuhan 430205China

Phosphate was removed from aqueous environment by corundum-hollow-spheres supported caclined hydrotalcite (cHT) thin films. Mg-Al-CO3 hydrotalcite (HT) thin films were deposited on corundumhollow-sphere substrates by hydrothermal homogeneous precipitation at 120℃for 30-240 min and cHT thin films were obtained by annealing of the HT thin films at 500℃for 180 min. Their crystal phase, morphology and microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).The results show that homogeneous, well-crystallized and hierarchical flower-like thin films were deposited firmly on the surface of the corundum. The mechanism of nucleation and growth of the HT thin films was fitted well with the anion coordination polyhedron growth unit model. To determine the absorption of phosphate by this adsorbent, different bed depth (10-30 cm) and flow rate (1.0-3.0 m L/min) were examined by column experiments. The highest removal efficiency of phosphate amounted to 98.5%under optimum condition (pH=7.2). The adsorption capacity increased as the bed depth increased and decreased as the flow rate increased.

关键词： adsorption phosphate hydrotalcite corundum-hollow-sphere hydrothermal homogeneous precipitation thermal anneal