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Discrimination of Pb-Zn deposit types using sphalerite geochemistry: New insights from machine learning algorithm

Geoscience Frontiers 2023年第4期14卷 200-219页

作者： Xiao-Ming li Yi-Xin zhang zhan-ke li Xin-Fu Zhao Ren-Guang Zuo Fan Xiao Yi Zheng School of Earth Resources China University of GeosciencesWuhanHubei Province 430074China School of Computer Science China University of GeosciencesWuhanHubei Province 430078China State key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China School of Earth Sciences and Engineering Sun Yat-Sen UniversityZhuhaiGuangdong Province 519000China

Due to the combined influences such as ore-forming temperature,fluid and metal sources,sphalerite tends to incorporate diverse contents of trace elements during the formation of different types of Lead-zinc(Pb-Zn)***,trace elements in sphalerite have long been utilized to distinguish Pb-Zn deposit ***,previous discriminant diagrams usually contain two or three dimensions,which are limited to revealing the complicated interrelations between trace elements of sphalerite and the types of Pb-Zn *** this study,we aim to prove that the sphalerite trace elements can be used to classify the Pb-Zn deposit types and extract key factors from sphalerite trace elements that can dis-criminate Pb-Zn deposit types using machine learning algorithms.A dataset of nearly 3600 sphalerite spot analyses from 95 Pb-Zn deposits worldwide determined by LA-ICP-MS was compiled from peer-reviewed publications,containing 12 elements(Mn,Fe,Co,Cu,Ga,Ge,Ag,Cd,In,Sn,Sb,and Pb)from 5 types,including Sedimentary Exhalative(SEDEX),Mississippi Valley Type(MVT),Volcanic Massive Sulfide(VMS),skarn,and epithermal *** Forests(RF)is applied to the data processing and the results show that trace elements of sphalerite can successfully discriminate different types of Pb-Zn deposits except for VMS deposits,most of which are falsely distinguished as skarn and epithermal *** further discriminate VMS deposits,future studies could focus on enlarging the capacity of VMS deposits in datasets and applying other geological factors along with sphalerite trace elements when con-structing the classification ***’s feature importance and permutation feature importance were adopted to evaluate the element significance for ***,a visualized tool,t-distributed stochastic neighbor embedding(t-SNE),was used to verify the results of both classification and *** results presented here show that Mn,Co,and Ge display significant impacts on classifica

关键词： Discrimination Pb-Zn deposit Sphalerite trace elements Machine learning algorithms Feature analysis

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UAV maneuvering decision-making algorithm based on deep reinforcement learning under the guidance of expert experience

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Journal of Systems Engineering and Electronics 2024年第3期35卷 644-665页

作者： zhan Guang zhanG Kun li ke PIAO Haiyin School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072China Science and Technology on Electro-Optic Control Laboratory Luoyang 471009China

Autonomous umanned aerial vehicle(UAV) manipulation is necessary for the defense department to execute tactical missions given by commanders in the future unmanned battlefield. A large amount of research has been devoted to improving the autonomous decision-making ability of UAV in an interactive environment, where finding the optimal maneuvering decisionmaking policy became one of the key issues for enabling the intelligence of UAV. In this paper, we propose a maneuvering decision-making algorithm for autonomous air-delivery based on deep reinforcement learning under the guidance of expert experience. Specifically, we refine the guidance towards area and guidance towards specific point tasks for the air-delivery process based on the traditional air-to-surface fire control ***, we construct the UAV maneuvering decision-making model based on Markov decision processes(MDPs). Specifically, we present a reward shaping method for the guidance towards area and guidance towards specific point tasks using potential-based function and expert-guided advice. The proposed algorithm could accelerate the convergence of the maneuvering decision-making policy and increase the stability of the policy in terms of the output during the later stage of training process. The effectiveness of the proposed maneuvering decision-making policy is illustrated by the curves of training parameters and extensive experimental results for testing the trained policy.

关键词： unmanned aerial vehicle(UAV) maneuvering decision-making autonomous air-delivery deep reinforcement learning reward shaping expert experience

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Driver at 10 MJ and 1 shot/30 min for inertial confinement fusion at high gain:Efficient,compact,low-cost,low laser-plasma instabilities,beam color selectable from 2ω/3ω/4ω,applicable to multiple laser fusion schemes

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Matter and Radiation at Extremes 2024年第4期9卷 4-7页

作者：隋展蓝可 Shanghai Institute of Laser Plasma China Academy of Engineering PhysicsShanghai 201800China Instituteof Applied Physics and Computational Mathematics Beijing 100094China

The achievement of ignition at the National Ignition Facility(NIF)has prompted a global wave of further research on inertial fusion energy(IFE).However,IFE requires a target gain G of 30-100,and it is hard to achieve fusion at such high gain with the energy,configuration,and technical approach of the ***,we present a conceptual design for a next-generation laser driver that is applicable to multiple laser fusion schemes and provides 10 MJ,2-3 PW at 3ω(or 2ω,in which case the energy and power can be higher),and one shot per 30 min,with the aim of achieving G>*** is also efficient,compact,and low in cost,and it has low susceptibility to laser-plasma instabilities.

关键词： applicable compact instabilities

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MARS and RNAcmap3:The Master Database of All Possible RNA Sequences Integrated with RNAcmap for RNA Homology Search

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Genomics, Proteomics & Bioinformatics 2024年第1期22卷 143-150页

作者： ke Chen Thomas litfin Jaswinder Singh Jian zhan Yaoqi Zhou Institute of Systems and Physical Biology Shenzhen Bay LaboratoryShenzhen 518055China Peking University Shenzhen Graduate School Shenzhen 518055China University of Science and Technology of China Hefei 230026China Suzhou Institute for Advanced Research University of Science and Technology of ChinaSuzhou 215123China Institute for Glycomics Griffith UniversitySouthportQLD 4222Australia

sequences found in the huge,integrated database of protein sequences(Big Fantastic Database).In contrast,the existing nucleotide databases were not consolidated to facilitate wider and deeper homology ***,we built a comprehensive database by incorporating the non-coding RNA(ncRNA)sequences from RNAcentral,the transcriptome assembly and metagenome assembly from metagenomics RAST(MG-RAST),the genomic sequences from Genome Warehouse(GWH),and the genomic sequences from MGnify,in addition to the nucleotide(nt)database and its subsets in National Center of Biotechnology Information(NCBI).The resulting Master database of All possible RNA sequences(MARS)is 20-fold larger than NCBI’s nt database or 60-fold larger than *** new dataset along with a new split-search strategy allows a substantial improvement in homology search over existing state-of-the-art *** also yields more accurate and more sensitive multiple sequence alignments(MSAs)than manually curated MSAs from Rfam for the majority of structured RNAs mapped to *** results indicate that MARS coupled with the fully automatic homology search tool RNAcmap will be useful for improved structural and functional inference of ncRNAs and RNA language models based on *** is accessible at https://***/omix/release/OMIX003037,and RNAcmap3 is accessible at http://***/download/.

关键词： RNA sequence database Homology search Secondary structure MARS RNAcmap3

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Critical Metals Ga,Ge and In in the Global Pb-Zn Deposits:Current Understanding,Challenges and Perspectives

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Journal of Earth Science 2023年第4期34卷 1308-1311页

作者： Yi Zheng Peng-Peng Yu zhan-ke li Suo-Fei Xiong ling-li Zhou Jia-Xi Zhou ChangMing Wang Yu-Miao Meng Yu zhang Ye-Jian Wang Jing Xu Yue Wu Lan-Xuan Guo Taiping Zhao Guangdong Provincial key Lab of Geological Process and Mineral Resources Survey School of Earth Sciences and Geological EngineeringSun Yat-sen UniversityGuangzhou 510275China State key Laboratory of Geological Processes and Mineral Resources School of Earth ResourcesChina University of GeosciencesWuhan 430074China Collaborative Innovation Center for Exploration of Strategic Mineral Resources China University of GeosciencesWuhan 430074China Department of Earth Sciences Vrije Universiteit Amsterdam de Boelelaan 1085Amsterdam 1081HVNetherlands key Laboratory of Critical Minerals Metallogeny in Universities of Yunnan Province School of Earth SciencesYunnan UniversityKunming 650500China State key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences and ResourcesChina University of GeosciencesBeijing 100083China State key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of ScienceGuiyang 550081China key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring School of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China key Laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Zijin School of Geology and Mining Fuzhou UniversityFuzhou 350108China key Laboratory of Exploration Technologies for Oil and Gas Resources Key Laboratory of Petroleum Geochemistry and EnvironmentYangtze UniversityWuhan 430100China Zhongjin lingnan Nonfemetal Co. LtdShenzhen 518000China key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

BACKGROUND A spectrum of strategically critical metals, such as gallium(Ga), germanium(Ge) and indium(In), with promising applications in green and high-tech fields, are produced as byproducts of zinc ores in a variet... 详细信息

关键词： magmatic hydrothermal porphyry

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Strong Edge Coloring of Outerplane Graphs with Independent Crossings

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 467-477页

作者： ke-Jie li Xin zhanG School of Mathematics and Statistics Xidian UniversityXi’an 710071China

The strong chromatic index of a graph is the minimum number of colors needed in a proper edge coloring so that no edge is adjacent to two edges of the same *** outerplane graph with independent crossings is a graph embedded in the plane in such a way that all vertices are on the outer face and two pairs of crossing edges share no common end *** is proved that every outerplane graph with independent crossings and maximum degreeΔhas strong chromatic index at most 4Δ-6 if Δ≥4,and at most 8 ifΔ≤*** bounds are sharp.

关键词： outer-1-planar graph IC-planar graph strong edge coloring crossing

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Context‑dependent antioxidant defense system(ADS)‑based stress memory in response to recurrent environmental challenges in congeneric invasive species

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Marine life Science & Technology 2024年第2期6卷 315-330页

作者： Hanxi li Xuena Huang Aibin zhan Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Marine ecosystems are facing escalating environmental fluctuations owing to climate change and human activities,imposing pressures on marine *** withstand recurring environmental challenges,marine organisms,especially benthic species lacking behavioral choices to select optimal habitats,have to utilize well-established strategies such as the antioxidant defense system(ADS)to ensure their ***,understanding of the mechanisms governing the ADS-based response is essential for gaining insights into adaptive strategies for managing environmental *** we conducted a com-parative analysis of the physiological and transcriptional responses based on the ADS during two rounds of'hypersalinity-recovery'challenges in two model congeneric invasive ascidians,Ciona robusta and *** results demonstrated that *** exhibited higher tolerance and resistance to salinity stresses at the physiological level,while *** demonstrated heightened responses at the transcriptional *** observed distinct transcriptional responses,particularly in the utilization of two superoxide dismutase(SOD)*** Ciona species developed physiological stress memory with elevated total SOD(T-SOD)and glutathione(GSH)responses,while only *** demonstrated transcriptional stress *** regulatory distinctions within the Nrf2-keap1 signalling pathway likely explain the formation disparity of transcriptional stress memory between both Ciona *** findings support the'context-dependent stress memory hypothesis',emphasizing the emergence of species-specific stress memory at diverse regulatory levels in response to recurrent environmental *** results enhance our understanding of the mechanisms of environmental challenge manage-ment in marine species,particularly those related to the ADS.

关键词： Antioxidant defense Ascidian Biological invasion Environmental stress Stress memory

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Priority effects of forbs arriving early:the role of root interaction and asymmetric competition

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Ecological Processes 2024年第1期13卷 53-65页

作者： Xiaohong Yan Xiliang li ke Jin Institute of Grassland Research Chinese Academy of Agricultural Sciences

Background The priority effect of plant arrival is a key driver of community assembly and ecosystem succession during the restoration of degraded plant communities. However, the significance of the arrival order of different plant functional groups and their interactions with community assemblies remains unclear. Using a phytotron experiment with three fully crossed factors, we investigated the underlying mechanisms of priority effects and their relationships with the biomass and biodiversity effects in mixed plant communities by manipulating the order of arrival of species, isolation of roots, and removal of specific *** The results showed that the strength and direction of priority effects were influenced by arrival order, root interactions, asymmetric competition among species, and their interactions. The identities of early and late-sown species also determined the magnitude of priority effects. The priority effects were stronger in grass-first(24.76%) and legume-first communities(24.48%) than in forb-first communities. The pot biomass of the different priority treatments was highest in grass-first(5.85 g), followed by legume-first(3.94 g) and forb-first(2.48 g). The order of arrival in the mixture significantly affected the net biodiversity effects(P lies. In addition, the importance of the priority effect of forbs sown first is related to community assembly, which may be a key determinant in successfully establishing a highly diverse community in the early stages of restoration. Species with weak competition should be considered in the early stage of community ass

关键词： Community assembly Order of arrival Overyielding Plant functional group Root isolation

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Surface Elastic Effects on Electromechanical Responses of a Piezoelectric Semiconducting Nanobeam

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Acta Mechanica Solida Sinica 2024年第4期37卷 598-612页

作者： Aowen Bao Xiaobao li Yuxue Pu Chunxiao zhan School of Civil Engineering Hefei University of TechnologyHefei230009China

Piezoelectric semiconductors(PSCs)find extensive applications in modern smart electronic devices because of their dual properties of being piezoelectric and *** the increasing demand for miniaturization of these devices,the performance of their components needs to be carefully designed and optimized,especially when reduced to *** has been shown that surface elastic properties play a substantial role in the mechanical performance of nanoscale materials and *** on this understanding,the surface elastic effects,encompassing surface residual stress,surface membrane stiffness,and surface bending stiffness,are comprehensively taken into account to explore the electromechanical responses of a PSC ***,the flexoelectric effect on their responses is also systematically *** results of this work reveal that surface elastic properties predominantly influence mechanical performance,while the flexoelectric effect plays a more dominant role in electric-related quantities at the ***,the significance of surface bending rigidity,which was often underestimated in the earlier literature,is ***,owing to the flexoelectric effect,the linear distribution of electric potential and charge carriers along the length transforms into a nonlinear *** distributions of electric potential and charge carriers across the cross section are also evidently ***,the size-dependent responses are *** findings may provide valuable insights for optimizing electronic devices based on nanoscale PSCs.

关键词： Surface elastic effect Flexoelectricity Size effect Piezoelectric semiconductor

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Experimental investigation of engineered geopolymer composite for structural strengthening against blast loads

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Defence Technology（防务技术） 2024年第2期32卷 496-509页

作者： Shan liu Chunyuan liu Yifei Hao Yi zhang li Chen zhan li key Laboratory of Coast Civil Structure Safety of Ministry of Education Tianjin UniversityTianjin 300072China Tianjin key Laboratory of Prefabricated Buildings and Intelligent Construction Hebei University of TechnologyTianjin 300400China Institute of Defense Engineering AMSPLABeijing 100850China Engineering Research Center of Safety and Protection of Explosion&Impact of Ministry of Education Southeast UniversityNanjing 211189JiangsuChina State key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of the PLANanjing 210007JiangsuChina

The recent increase in blast/bombing incidents all over the world has pushed the development of effective strengthening approaches to enhance the blast resistance of existing civil *** geopolymer composite(EGC)is a promising material featured by eco-friendly,fast-setting and strain-hardening characteristics for emergent strengthening and ***,the fiber optimization for preparing EGC and its protective effect on structural elements under blast scenarios are *** this study,laboratory tests were firstly conducted to evaluate the effects of fiber types on the properties of EGC in terms of workability,dry shrinkage,and mechanical properties in compression,tension and *** experimental results showed that EGC containing PE fiber exhibited suitable workability,acceptable dry shrinkage and superior mechanical properties compared with other types of *** that,a series of field tests were carried out to evaluate the effectiveness of EGC retrofitting layer on the enhancement of blast performance of typical *** tests include autoclaved aerated concrete(AAC)masonry walls subjected to vented gas explosion,reinforced AAC panels subjected to TNT explosion and plain concrete slabs subjected to contact *** was found that EGC could effectively enhance the blast resistance of structural elements in different *** AAC masonry walls and panels,with the existence of EGC,the integrity of specimens could be maintained,and their deflections and damage were significantly *** plain concrete slabs,the EGC overlay could reduce the diameter and depth of the crater and spallation of specimens.

关键词： Engineered geopolymer composites Fiber optimization Strengthening material Blast resistance Masonry wall Reinforced AAC panel Plain concrete slab

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