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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

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

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 ChinaHefei 230026China

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,*** practical applications,quadric surfaces,which are the most basic type of surfaces,are typically bounded surfaces trimmed by a sequence of *** 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 *** 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 *** error control is based on an effective solution to a set of polynomial inequality system using the root isolation *** 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

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

Near-field wideband beam training for ELAA with uniform circular array

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Science China(Information Sciences) 2024年第6期67卷 370-383页

作者： Yuhao chen Linglong DAI Department of Electronic Engineering Tsinghua UniversityBeijing National Research Center for Information Science and Technology (BNRist)

Extremely large-scale antenna array(ELAA) at millimeter wave(mmWave) and Terahertz(THz)band has been considered a key technology for combating high attenuation in high-frequency bands in future6G communications. Uniform circular arrays(UCAs) have attracted much attention because of their ability to provide flat beamforming gain at all angles. To realize efficient beamforming, beam training is widely used to acquire channel state information. However, with a large antenna number, the beam training overhead in ELAA systems becomes overwhelming. Moreover, with a large bandwidth, the beam defocus effect severely degrades beam training accuracy. To address these issues, this paper proposes a frequency-dependent focusing(FDF)-based beam training scheme to realize effective beam training in near-field wideband ELAA systems with UCA. Specifically, we first analyze the FDF property of UCA, where signals at different subcarriers can simultaneously focus on different distances. Then, by exploiting the FDF property to search different distances using different subcarriers simultaneously, we design a hierarchical codebook and propose an FDFbased beam training scheme. To reveal the effectiveness of the proposed scheme, we compare its necessary beam training overhead with that of existing schemes. Finally, the simulation results demonstrate that the proposed scheme can achieve accurate beam training in near-field wideband UCA systems with a low beam training overhead.

关键词： extremely large-scale antenna array (ELAA) uniform circular array (UCA) near-field wideband beam training

Molybdenum isotope composition of the upper mantle and its origin:insight from mid-ocean ridge basalt

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Journal of Oceanology and Limnology 2024年第3期42卷 705-708页

作者： Shuo chen Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China

The molybdenum(Mo)isotope system is pivotal in reconstructing marine redox changes throughout Earth’s history and has emerged as a promising tracer for igneous and metamorphic *** its composition and variation across major geochemical reservoirs is essential for its application in investigating high-temperature ***,there is debate regarding theδ^(98/95)Mo value of the Earth’s mantle,with estimates ranging from sub-chondritic to super-chondritic *** analyses of global mid-ocean ridge basalt(MORB)glasses revealed significantδ^(98/95)Mo variations attributed to mantle heterogeneity,proposing a two-component mixing model to explain the observed *** studies confirmed the sub-chondriticδ^(98/95)Mo of the depleted upper mantle,suggesting remixing of subduction-modified oceanic crust as a plausible *** findings underscore the role of Mo isotopes as effective tracers for understanding dynamic processes associated with mantle-crustal recycling.

关键词： molybdenum(Mo)isotope mantle crustal recycling mid-ocean ridge basalt(MORB)

TDP-43 is a key molecule accelerating development of Alzheimer’s disease following traumatic brain injury

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Neural Regeneration Research 2024年第5期19卷 955-956页

作者： Chu chen Department of Cellular and Integrative Physiology Long School of MedicineUniversity of Texas Health Science Center at San AntonioSan AntonioTXUSA

Currently,more than 55 million people have dementia worldwide and Alzheimer’s disease(AD)is one of the most common causes of dementia in ***,no effective therapies are currently available for the prevention and treatment of *** is largely due to our limited understanding of the mechanisms underlying the neuropathogenesis of *** has widely been recognized that AD is heterogeneous and that multi-factors are contributing to the pathogenesis of *** evidence suggests that traumatic brain injury(TBI)is an important risk factor for the development of AD and dementia later in life(Guo et al.,2000;Johnson et al.,2010).However,the precise mechanism by which TBI contributes to developing AD has yet to be elucidated.

关键词： Alzheimer traumatic

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

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.

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