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Digital Communications and Networks 2024年第2期10卷 282-291页

作者： Jiachen yang Meng Xi Jiabao wen yang Li Houbing Herbert Song School of Electrical and Information Engineering Tianjin UniversityTianjin300072China Security and Optimization for Networked globe Laboratory(SONg Lab) Embry-Riddle Aeronautical UniversityDaytona BeachFL32114USA

The Autonomous Underwater glider(AUg)is a kind of prevailing underwater intelligent internet vehicle and occupies a dominant position in industrial applications,in which path planning is an essential *** to the complexity and variability of the ocean,accurate environment modeling and flexible path planning algorithms are pivotal *** traditional models mainly utilize mathematical functions,which are not complete and *** existing path planning algorithms depend on the environment and lack *** overcome these challenges,we propose a path planning system for underwater intelligent internet *** applies digital twins and sensor data to map the real ocean environment to a virtual digital space,which provides a comprehensive and reliable environment for path *** design a value-based reinforcement learning path planning algorithm and explore the optimal network structure *** path simulation is controlled by a closed-loop model integrated into the terminal vehicle through edge *** integration of state input enriches the learning of neural networks and helps to improve generalization and *** task-related reward function promotes the rapid convergence of the *** experimental results prove that our reinforcement learning based path planning algorithm has great flexibility and can effectively adapt to a variety of different ocean conditions.

关键词： Digital twins Reinforcement learning Edge computing Underwater intelligent internet vehicle Path planning

Research progresses and prospects of multi-sphere compound extremes from the Earth System perspective

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Science China Earth Sciences 2024年第2期67卷 343-374页

作者： Zengchao HAO yang CHEN College of water Sciences Beijing Normal UniversityBeijing100875China State Key Laboratory of Severe weather Chinese Academy of Meteorological SciencesBeijing100081China

Compound extremes,whose socioeconomic and ecological impacts are severer than that caused by each event occurring in isolation,have evolved into a hot topic in Earth Science in the past *** the context of climate change,many compound extremes have exhibited increasing frequency and intensity,and shown novel fashions of combinations,posing more pressing demands and tougher challenges to scientific research and disaster prevention and *** article,via a perspective of multi-sphere interactions within the Earth System,systematically reviews the status quo,new scientific understanding,and deficiencies regarding the definition,mechanism,change,attribution,and projection of compound *** study also sorts out existing challenges and outlines a potential roadmap in advancing the study on compound extremes with respect to data requirement,mechanistic diagnosis,numerical modeling,attribution and projection,risk assessment,and adaptive *** directions of compound extremes studies and key research topics that warrant multi-disciplinary and multisectoral coordinated efforts are also *** that climate change has reshaped the type of extremes,a transformation from the traditional single-event perspective to a compound-event perspective is needed for scientific research,disaster prevention and mitigation,and climate change adaptation,calling for bottom-up innovation in research objects,ideas,and *** article will add value to promoting the research on compound extremes and interdisciplinary cooperations.

关键词： Extremes Compound extremes Climate change and risk Multi-sphere interactions

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RMPC-Based Visual Servoing for Trajectory Tracking of Quadrotor UAVs with Visibility Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 2027-2029页

作者： Qifan yang Huiping Li School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072China

Dear Editor,This letter deals with the tracking problem of quadrotors subject to external disturbances and visibility constraints by designing a robust model predictive control(RMPC) scheme. According to the imagebase... 详细信息

关键词： Visual image visibility

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Bioinspired supramolecular macrocycle hybrid membranes with enhanced proton conductivity

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Nano Research 2024年第2期17卷 797-805页

作者： Pengfei yang Linlin Xu Panagiotis Trogadas Marc-Olivier Coppens yang Lan Centre for Nature Inspired Engineering Department of Chemical EngineeringUniversity College LondonLondon WC1E 7JEUK

Enhancing the proton conductivity of proton exchange membranes(PEMs)is essential to expand the applications of proton exchange membrane fuel cells(PEMFCs).Inspired by the proton conduction mechanism of bacteriorhodopsin,cucurbit[n]urils(CB[n],where n is the number of glycoluril units,n=6,7,or 8)are introduced into sulfonated poly(ether ether ketone)(SPEEK)matrix to fabricate hybrid PEMs,employing a nature-inspired chemical engineering(NICE)*** carbonyl groups of CB[n]act as proton-conducting sites,while the host–guest interaction between CB[n]and water molecules offers extra protonconducting ***,the molecular size of CB[n]aids in their dispersion within the SPEEK matrix,effectively bridging the unconnected proton-conducting sulfonic group domains within the SPEEK ***,all hybrid membranes exhibit significantly enhanced proton ***,the SPEEK membrane incorporating 1 wt.%CB[8](CB[8]/SPEEK-1%)demonstrates the highest proton conductivity of 198.0 mS·cm^(−1) at 60°C and 100%relative humidity(RH),which is 228%greater than that of the pure SPEEK membrane under the same ***,hybrid membranes exhibit superior fuel cell *** CB[8]/SPEEK-1%membrane achieves a maximum power density of 214 mw·cm^(−2),representing a 140%improvement over the pure SPEEK membrane(89 mw·cm^(−2))at 50°C and 100%*** findings serve as a foundation for constructing continuous proton-conducting pathways within membranes by utilizing supramolecular macrocycles as fuel cell electrolytes and in other applications.

关键词： supramolecular macrocycle proton conductivity cucurbit[n]uril proton exchange membrane fuel cell

Origin of nucleation and growth of extension twins in grains unsuitably oriented for twinning during deformation of Mg-1%Al

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Journal of Magnesium and Alloys 2024年第3期12卷 1186-1203页

作者： Biaobiao yang Javier LLorca IMDEA Materials Institute C/Eric Kandel 2GetafeMadrid 28906Spain Department of Materials Science Polytechnic University of Madrid/Universidad Politécnica de MadridE.T.S.de Ingenieros de CaminosMadrid 28040Spain

A large number of anomalous extension twins,with low or even negative twinning Schmid factors,were found to nucleate and grow in a strongly textured Mg-1Al alloy during tensile deformation along the extruded *** deformation mechanisms responsible for this behaviour were investigated through in-situ electron back-scattered diffraction,grain reference orientation deviation,and slip trace-modified lattice *** was found that anomalous extension twins nucleated mainly at the onset of plastic deformation at or near grain boundary triple *** were associated with the severe strain incompatibility between neighbour grains as a result from the differentbasal slip-induced lattice ***,the anomalous twins were able to grow with the applied strain due to the continuous activation ofbasal slip in different neighbour grains,which enhanced the strain *** results reveal the complexity of the deformation mechanisms in Mg alloys at the local level when deformed along hard orientations.

关键词： Magnesium Extension twinning In-situ electron back-scattered diffraction basal slip Deformation mechanisms.

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Theoretical study on the synergistic mechanism of Fe-Mn in sodium-ion batteries

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PARTICUOLOgY 2024年第10期93卷 284-290页

作者： You, yang Yuan, Mingliang Cent South Univ Sch Mineral Proc & Bioengn Changsha 410083 Peoples R China

This article conducts first-principles calculations to initially explore the construction of two configurations, NaFeO2 2 (NFO) and NaMnO2 2 (NMO), and studies the mixing enthalpies under different Fe-Mn ratios. The results indicate that NaFe3/8Mn5/8O2 3/8 Mn 5/8 O 2 (NFMO) exhibits the most thermodynamically stable structure. Subsequent calculations on the mixing enthalpies and volume changes during the sodium extraction process for NFO, NMO, and NFMO configurations are presented, along with the partial density of states (PDOS) and Bader charges of transition metals (TM) and oxygen. These calculations reveal the synergistic mechanism of Fe and Mn. Fe and Mn can engage in more complex electron exchanges during sodium extraction, optimizing the internal electron density distribution and overall charge balance, thereby stabilizing the crystal structure and reducing the migration of Fe3 & thorn; 3 & thorn; to the sodium layers during deep sodium extraction. The interaction between Fe's 3d electrons and Mn's 3d electrons through the shared oxygen atoms' 2p orbitals occurs in the Fe-Mn-O network. This interaction can lead to a rebalancing of the electron density around Mn3+ 3 + atoms, mitigating the asymmetric electron density distribution caused by the d 4 configuration of the lone Mn3+ 3 + and suppressing the Jahn-Teller effect of Mn3 & thorn;. 3 & thorn; . Moreover, the synergistic effects between Fe and Mn can provide a more balanced charge distribution, reducing extreme changes to the charge state of oxygen atoms and decreasing the irreversible oxygen release caused by anionic redox reactions during deep sodium extraction, thereby enhancing the material's stability. This in-depth study of the interaction mechanism at the microscopic level when co- doping Fe and Mn offers valuable insights for the rational design and development of high-performance cathode materials. (c) 2024 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sci

关键词： First-principles calculations Sodium-ion batteries Layered oxides NaFe 3/8 Mn 5/8 TOTAL-ENERgY CALCULATIONS CATHODE PERFORMANCE LI

Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu yang Li Yu Liu Xiao-Xiao Ling Li-guang wu Li yang Lan yang Bo yang Yong-gang Zhao Xian-Hua Li State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. with extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. while quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

Deficiency of Trp53 and Rb1 in myeloid cell lineage spontaneously develops acute myeloid leukemia in a mouse model

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genes & Diseases 2024年第1期11卷 4-6页

作者： yang Li Shu-ting yang Shuying yang Department of Basic&Translational Sciences School of Dental MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA Department of Orthopaedic Surgery School of MedicineJohns Hopkins University BaltimoreMD 21205USA Center for Innovation&Precision Dentistry School of Dental MedicineSchool of Engineering and Applied SciencesUniversity of PennsylvaniaPhiladelphiaPA 19104USA The Penn Center for Musculoskeletal Disorders School of MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA

Acute myeloid leukemia(AML)is a rapidly lethal blood cancer characterized by aberrant proliferation and differentiation of myeloid progenitors in the hematopoietic *** recent decades,AML patients are significantly *** 2019 alone,21,450 new AML cases were diagnosed in the United States,with an estimated 10,920 deaths due to ***’s worse,AML occurs with an increasing incidence with advanced age,and the survival rate remains dismal with a median overall survival of only 5e10 *** great advances in allogenic transplant and chemotherapy,the therapeutic outcomes are unfavorable due to the disease relapse and mortality *** importantly,the development of more specific and effective therapies was hampered in part by the lack of proper animal models for ***,management and elucidation of the pathological mechanism of AML remain an ongoing challenge,and the development of effective AML mouse models and treatment options are urgently needed.

关键词： myeloid Acute leukemia

Time-Aware LSTM Neural Networks for Dynamic Personalized Recommendation on Business Intelligence

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Tsinghua Science and Technology 2024年第1期29卷 185-196页

作者： Xuan yang James A.Esquivel graduate School Angeles University FoundationAngeles City 2009Philippines Shandong Provincial University Laboratory for Protected Horticulture Weifang University of Science and TechnologyWeifang 262700China

Personalized recommendation plays a critical role in providing decision-making support for product and service analysis in the field of business ***,deep neural network-based sequential recommendation models gained considerable ***,existing approaches pay litle attention to users'dynamically evolving interests,which are influenced by product attributes,especially product *** overcome these challenges,we propose a dynamic personalized recommendation model:***,we first embed product information and attribute information into a unified data ***,we exploit long short-term memory(LsTM)networks to characterize sequential behavior over multiple time periods and seize evolving interests by hierarchical LSTM ***,similarity values between users are measured through pairwise interest features,and personalized recommendation lists are generated.A series of experiments reveal the superiority of the proposed method compared withotheradvanced methods.

关键词： personalized recommendations evolving interests embedding LsTM networks

Risk-Averse Two-Stage Distributionally Robust Economic Dispatch Model Under Uncertain Renewable Energy

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1514-1524页

作者： Ce yang weiqing Sun Jiannan yang Dong Han Department of Control Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China Department of Electrical Engineering University of Shanghai for Science and TechnologyShanghai 200093China School of Economics and Business Administration Chongqing UniversityChongqing 400044China

with the participation of large quantities of renewable energy in power system operations,their volatility and intermittence increases the difficulties and challenges of power system economic *** the uncertainty of renewable energy generation,based on the distributionally robust optimization method,a two-stage economic dispatch model is proposed to minimize the total operation *** this paper,it is assumed that the fluctuating of renewable power generation follows the unknown probability distribution that is restricted in an ambiguity set,which is established by utilizing the first-order moment information of available historical ***,the theory of conditional value-at-risk is introduced to transform the model into a tractable model,which we call robust counterpart *** on the stochastic dual dynamic programming method,an improved iterative algorithm is proposed to solve the robust counterpart ***,the convergence optimum can be obtained by the improved iterative algorithm,which performs a forward pass and backward pass repeatedly in each iterative ***,by comparing with other methods,the results on the modified IEEE 6-bus,118-bus,and 300-bus system show the effectiveness and advantages of the proposed model and method.

关键词： Energy and reserve co-dispatch distributionally robust conditional value-at-risk stochastic dual dynamic programming