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Collaborative Trajectory Planning for Stereoscopic Agricultural Multi-UAVs Driven by the Aquila Optimizer

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Computers, Materials & Continua 2025年第1期82卷 1349-1376页

作者： Xinyu liu Longfei Wang Yuxin Ma Peng Shao School of Computer and Information Engineering Jiangxi Agricultural UniversityNanchang330045China

Stereoscopic agriculture,as an advanced method of agricultural production,poses new challenges for multi-task trajectory planning of unmanned aerial vehicles(UAVs).To address the need for UAVs to perform multi-task trajectory planning in stereoscopic agriculture,a multi-task trajectory planning model and algorithm(IEP-ao)that synthesizes flight safety and flight efficiency is *** on the requirements of stereoscopic agricultural geomorphological features and operational characteristics,the multi-task trajectory planning model is ensured by constructing targeted constraints at five aspects,including the path,slope,altitude,corner,energy and obstacle threat,to improve the effectiveness of the trajectory planning *** combined with the path optimization algorithm,an Aquila optimizer(IEP-ao)based on the interference-enhanced combination model is proposed,which can help UAVs to improve the trajectory search capability in complex operation space and large-scale operation tasks,and jump out of the locally optimal trajectory path region timely,to generate the optimal trajectory planning plan that can adapt to the diversity of the tasks and the flight ***,four simulated flights with different operation scales and different scene constraints were conducted under the constructed real 3Dimension scene,and the experimental results can show that the proposedmulti-task trajectory planning method canmeet themulti-task requirements in stereoscopic agriculture and improve the mission execution efficiency and agricultural production effect of UAV.

关键词： Stereoscopic agriculture unmanned aerial vehicle multi-task interference model Aquila optimizer

Cu and Zn Isotopic Evidence for the Magnitude of Organic Burial in the Mesoproterozoic Ocean

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Journal of Earth Science 2022年第1期33卷 92-99页

作者： Yiwen Lü Sheng-ao liu State Key Laboratory of Geological Processes and Mineral Resources and Institute of Earth SciencesChina University of GeosciencesBeijing 100083China

The rate of net primary production in the Proterozoic ocean was suggested to be no more than 10% of its modern value(Laakso and Schrag,2019),however,in the Mesoproterozoic Xiamaling Formation,the export production values could reach 20%-150% of the present-day Equatorial Atlantic average values(Zhang et al.,2016).Here,we report Zn and Cu isotope data for black shales from the Xiamaling Formation to illustrate the biogeochemical cycling of Zn and Cu in the Mesoproterozoic *** ^(65)Cu-enriched signature in the authigenic fraction is similar to that in bioauthigenic Cu of the modern marine *** Zn isotope ratios of sediments deposited in euxinic conditions are commonly higher than those of clastic sediments,indicating light Zn sinks in the coeval *** with previously reported Mo isotope data,the proportion of organic carbon to total carbon burial in the Mesoproterozoic was about as half as that at present,which is larger than the previous estimation―a quarter of today’s value(e.g.,Ozaki et al.,2019) and is evidenced by a wide distribution of black *** organic burial may be ascribed to the increasing phosphorus inputs from large igneous provinces and consequently high primary productivity,which has spurred the hypothesized atmosphere-ocean oxygenation at ~1.4 Ga.

关键词： zinc isotopes organic carbon Xiamaling Formation

Copper Isotope Fractionation during Basalt Leaching at 25℃ and pH=0.3,2

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Journal of Earth Science 2022年第1期33卷 82-91页

作者： Dandan Li Sheng-ao liu State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China

The geochemical cycling of copper in the hydrosphere and soil environments primarily involves the transport of Cu from rocks to rivers via *** the factors controlling Cu isotope fractionation during weathering is crucial for the purpose of using Cu isotopes as a tracer of geochemical ***,we performed acid-leaching experiments on natural basalts (BHVO-2 and GBW07105) and chalcopyrite in Erlenmeyer flasks at T=25℃ and different pH values (0.3 and 2).Our results reveal substantial Cu isotope fractionations (△^(65)Cu_(solution-initial)) between leachates (Cu_(solution)) and starting materials (Cu_(initial)).The leachates released from GBW07105 and chalcopyrite are consistently enriched in heavier Cu isotopes relative to the starting materials at pH=***,the δ^(65)Cu_(solution)values decrease to about-0.6‰first,then increase to>0 for BHVO-2 at pH=2 and GBW07105 at pH=*** results indicate that leaching of natural rocks by acidic liquids can produce both positive and negative Cu isotope fractionation,depending on pH values and the types of minerals in starting materials.X-ray power diffraction analysis (XRD) patterns reveal similar mineral assemblages between starting basalts and residues after each reaction *** most likely mechanisms responsible for such Cu isotope fractionation are the relative rates of Cu oxidation at the surface and Cu release into solution,and the sequence of mineral *** study represents an important step for future studies to use Cu isotopes to explain Cu isotopic variations in natural rocks and waters.

关键词： Cu isotopes isotope fractionation basalt chalcopyrite leaching

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An Inverse Power Generation Mechanism Based Fruit Fly Algorithm for Function Optimization

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Journal of Systems Science & Complexity 2019年第2期32卷 634-656页

作者： liu ao DENG Xudong REN Liang liu Ying liu Bo School of Management Wuhan University of Science and Technology Center for Service Science and Engineering Wuhan University of Science and Technology Hubei Province Key Laboratory of Intelligent Information Processing and Real-time Industrial System School of Economics and Management Beihang University Academy of Mathematics and Systems Science Chinese Academy of Sciences

As a novel population-based optimization algorithm, fruit fly optimization(FFO) algorithm is inspired by the foraging behavior of fruit flies and possesses the advantages of simple search operations and easy implementation. Just like most population-based evolutionary algorithms, the basic FFO also suffers from being trapped in local optima for function optimization due to premature *** this paper, an improved FFO, named IPGS-FFO, is proposed in which two novel strategies are incorporated into the conventional FFO. Specifically, a smell sensitivity parameter together with an inverse power generation mechanism(IPGS) is introduced to enhance local exploitation. Moreover,a dynamic shrinking search radius strategy is incorporated so as to enhance the global exploration over search space by adaptively adjusting the searching area in the problem domain. The statistical performance of FFO, the proposed IPGS-FFO, three state-of-the-art FFO variants, and six metaheuristics are tested on twenty-six well-known unimodal and multimodal benchmark functions with dimension 30, respectively. Experimental results and comparisons show that the proposed IPGS-FFO achieves better performance than three FFO variants and competitive performance against six other meta-heuristics in terms of the solution accuracy and convergence rate.

关键词： Evolutionary algorithms fruit fly optimization function optimization meta-heuristics

Copper isotope constraints on the origins of basaltic and andesitic magmas in the Tengchong volcanic field,SE Tibet

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Geoscience Frontiers 2024年第4期15卷 290-303页

作者： Yuan-Ru Qu Sheng-ao liu State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China

The Tengchong volcano field(TVF),situated at the southeastern margin of the Tibetan Plateau,holds crucial information regarding Cenozoic volcanic activities and geotectonic evolution of the SE *** provide new constraints on petrogenesis and evolution of the Tengchong volcanism,here we conducted copper(Cu)elemental and isotopic analyses on a suite of samples that document the evolution from basalts to andesites in the *** basalts are Cu-depleted(29.7-36.9 ppm)and have higherδ65Cu val-ues(0.19‰-0.40‰,mean=0.31‰±0.05‰;n=11)than those of mid-ocean ridge basalts(MORBs,~0.09‰)and the mantle(~0.06‰)as well as the majority of island arc *** with the low Cu/Zr ratios,these characteristics are interpreted to reflect the fractionation of isotopically light sulfides in the S-saturated systems during magma ascent,rather than source heterogeneity induced by recycled materials and redox *** with the basalts,the andesites have slightly lower Cu contents(14.4-29.4 ppm)and lighter Cu isotopic compositions(mean=-0.14‰±0.06‰;n=13).These differences cannot be attributed to progressive sulfide fractionation of basaltic magmas but require the assimilation of lower crustal materials with lowδ65Cu values during evolution of the andesitic *** results collectively suggest that Cu isotopes can provide valuable insights into magma origin and evolution.

关键词： Copper isotopes Sulfide segregation Magmatic differentiation Tengchong volcanic field

Generalized degradation reliability model considering phase transition

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Journal of Systems Engineering and Electronics 2022年第3期33卷 748-758页

作者： ZHANG ao WANG Zhihua WU Qiong liu Chengrui School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Institute of Spacecraft System Engineering China Academy of Space TechnologyBeijing 100094China Beijing Institute of Control Engineering Beijing 100094China

Aiming to evaluate the reliability of phase-transition degrading systems,a generalized stochastic degradation model with phase transition is constructed,and the corresponding analytical reliability function is formulated under the concept of the first hitting *** phase-varying stochastic property and the phase-varying nonlinearity are considered simultaneously in the proposed *** capture the phase-varying stochastic pro-perty,a Wiener process is adopted to model the non-monotonous degradation phase,while a Gamma process is utilized to model the monotonous *** addition,the phase-varying non-linearity is captured by different transformed time scale *** facilitate the practical application of the proposed model,identification of phase model type and estimation of model parameters are discussed,and the initial guesses for parameters optimization are also *** on the constructed model,two simulation studies are carried out to verify the analytical reliability function and analyze the influence of model ***,a practical case study is conducted for illustration.

关键词： degradation phase transition reliability stochastic process nonlinearity

Flow cytometric assessment of the effects of chlorine, chloramine, and UV on bacteria by using nucleic acid stains and 5-cyano-2,3-ditolyltetrazolium chloride

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Frontiers of Environmental Science & Engineering 2016年第6期10卷 83-91页

作者： Xuebiao Nie Wenjun liu Mo Chen Minmin liu Lu ao School of Environment Tsinghua University Beijing 100084 China China Gezhouba Group Real Estate Corporation Beijing 100020 China Department of Architecture and Environmental Engineering Logistic Engineering University of PLA Chongqing 401331 China

Flow cytometry （FCM） has been widely used in multi-parametric assessment of cells in various research fields, especially in environmental sciences. This study detected the metabolic activity of Escherichia coli and Staphylococcus aureus by using an FCM method based on 5-cyano-2,3-ditolyltetrazolium chloride （CTC）; the accuracy of this method was enhanced by adding SYTO 9 and 10% R2A broth. The disinfection effects of chlorine, chloramine, and UV were subsequently evaluated by FCM methods. Chlorine demonstrated stronger and faster destructive effects on cytomembrane than chloramine, and nucleic acids decomposed afterwards. The metabolic activity of the bacteria persisted after the cytomembmnewas damaged as detected using CTC. Low-pressure （LP） UV or medium-oressure （MP） UV treatments exerted no significant effects on membrane permeability. The metabolic activityof the bacteria decreased with increasing UV dosage, and MP-UV was a stronger inhibitor of metabolic activity than LP-UV. Furthermore, the membrane of Gram-positive S. aureus was more resistant to chlorine/chloramine than that of Gram-negative E. coil In addition, S. aureus showed higher resistance to UV irradiation than E. coli.

关键词： Flow cytometry Escherichia coli Staphylococcus aureus UV CTC SYTO 9

Linking deep CO2 outgassing to cratonic destruction

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National Science Review 2022年第6期9卷 12-22页

作者： Zhao-Xue Wang Sheng-ao liu Shuguang Li Di liu Jingao liu State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences

Outgassing of carbon dioxide from the Earth's interior regulates the surface climate through deep *** we examine the role of cratonic destruction in mantle CO2outgassing via collating and presenting new data for Paleozoic kimberlites, Mesozoic basaltic rocks and their mantle xenoliths from the eastern North China Craton（NCC）, which underwent extensive destruction in the early Cretaceous. High Ca/Al and low Ti/Eu and δ26Mg are widely observed in lamprophyres and mantle xenoliths, which demonstrates that the cratonic lithospheric mantle（CLM） was pervasively metasomatized by recycled *** analysis of bubble-bearing melt inclusions shows that redox melting of the C-rich CLM produced carbonated silicate melts with high CO2content. The enormous quantities of CO2in these magmas,together with substantial CO2degassing from the carbonated melt–CLM reaction and crustal heating,indicate that destruction of the eastern NCC resulted in rapid and extensive mantle CO2emission, which partly contributed to the early Cretaceous greenhouse climate episode.

关键词： carbonate metasomatism lithospheric mantle CO2 outgassing deep carbon cycling cratonic destruction North China Craton

Reactive DC Magnetron Sputtering Deposition of Copper Nitride Thin Film

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Journal of Materials Science & Technology 2007年第4期23卷 468-472页

作者： Xing＇ao LI Zuli liu Kailun Yao Department of Physics Huazhong University of Science and Technology Wuhan 430074 China Scllool of Science Hubei Institute for Nationalities Enshi 445000 China International Center of Material Physics Chinese Academy of Science Shenyang 110016 China

Copper nitride thin film was deposited on glass substrates by reactive DC （direct current） magnetron sputtering at a 0.5 Pa N2 partial pressure and different substrate temperatures. The as-prepared film, characterized with X-Ray diffraction, atomic force microscopy, and X-ray photoelectron spectroscopy measurements, showed a composed structure of Cu3N crystallites with anti-ReO3 structure and a slight oxidation of the resulted *** crystal structure and growth rate of Cu3N films were affected strongly by substrate temperature. The preferred crystalline orientation of Cu3N films were （111） and （200） at RT, 100℃. These peaks decayed at 200℃ and 300℃ only Cu （111） peak was noticed. Growth of Cu3N films at 100℃ is the optimum substrate temperature for producing high-quality （111） Cu3N films. The deposition rate of Cu3N films estimated to be in range of 18-30 nm/min increased while the resistivity and the microhardness of Cu3N films decreased when the temperature of glass substrate increased.

关键词： DC magnetron sputtering Copper nitride thin film Resistivity Microhardness