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Geochronological and geochemical constraints on the petrogenesis and geodynamic process of Hemler,Vlinder,and Il'ichev seamount lavas in NW Pacific

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Science China Earth Sciences 2024年第6期67卷 1856-1871页

作者： xun WEI Yan zhang Xuefa SHI Hui zhang Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Geology Qingdao Marine Science and Technology CenterQingdao 266237China Shandong Key Laboratory of Deep Sea Mineral Resources Development(Preparatory) Qingdao 266061China

Oceanic intraplate volcanoes with linear age progressions are usually accepted to be derived from melting of an upwelling mantle *** seamount groups in NW Pacific,however,show complex age-distance relationships that are difficult to explain using the classic“mantle plume hypothesis”,and thus their origins are *** this study,we present ^(40)Ar-^(39)Ar age,geochemical,and Sr-Nd-Pb-Hf isotopic data of lavas from Hemler,Vlinder,and Il’ichev seamounts in NW Pacific,to elucidate their petrogenesis and geodynamic *** lavas from Hemler,Vlinder,and Il’ichev seamounts are classified as alkali basalt,basanite/nephelinite,and *** with Mg O>8 wt.%exhibit high contents of CaO,FeO^(T),and TiO_(2),similar to the composition of melts formed from reaction between carbonated eclogite-derived melts and fertile *** lavas have elevated Zr/Hf ratios(40.6-45.2)and negative Zr and Hf anomalies,indicating the presence of a carbonate component in the mantle *** are enriched in incompatible trace elements and have enriched mantle 1(EM1)-like SrNd-Pb-Hf isotopic *** isotopic compositions of Vlinder,Il’ichev basanite,and Hemler lavas in this study are similar to the Rarotonga *** occurring at the same seamount,the Il’ichev alkali basalts display more depleted SrNd-Hf isotopic compositions compared to Il’ichev *** to plate tectonic reconstruction results,the ages of Hemler(100.1 Ma),Vlinder pre-(100.2 Ma)and post-shield(87.5 Ma),and Il’ichev(56.4 Ma)lavas clearly deviate from the Macdonald,Arago,Rarotonga,and Samoa hotspot tracks,indicating that they cannot directly originate from mantle *** propose that in the mid-Cretaceous,when the Pacific plate passed over Rarotonga hotspot,melting of Rarotonga plume formed the Vlinder(main-shield stage),Pako,and Ioah *** Rarotonga(and possibly Samoa)plume materials would have been dispersed into the surrounding asthenosphere by mantle conve

关键词： Mantle plume Magellan seamount trail Carbonated mantle component Hotspot Lithosphere extension

Autonomy Evaluation of Unmanned Systems Based on Task Models

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Machine Intelligence Research 2024年第5期21卷 815-830页

作者： Yi Zou Zehao Ni xun Lei Chi zhang Key Laboratory of Complex Aviation Simulation System Beijing100076China State Key Laboratory of Multimodal Artificial Intelligence Systems(MAIS) Institute of AutomationChinese Academy of Sciences(CASIA)Beijing100190China Hong Kong Institute of Science&Innovation Chinese Academy of Sciences(HKISI CAS)Hong Kong999077China

In this study,relevant work on autonomy evaluation(AE)in recent years was comprehensively reviewed and classified from the perspective of task models,and a closed-loop task models based theoretical framework for AE was *** main contributions of this study are as follows.1)A taxonomy for AE based on task models was introduced to classify current theories,methods and standards.2)The limitations of the current autonomous evaluation methods were addressed to provide a theoretical framework for quantitative evaluation based on task models,and evaluation metrics for each stage were proposed based on the AE theoretical framework.3)Qualitative analyses of the superiority of the proposed AE framework based on the closed-loop task models were *** study attempts to provide a reference for researchers and engineers in the autonomous unmanned systems field and inspire future development of AE.

关键词： Unmanned system(UMS) autonomy evaluation task models closed-loop task models kill chain

Optimal Configuration of Multitype Energy Storage for Integrated Energy Systems Considering System Reserve Value

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 2114-2126页

作者： xun Dou Jun Wang Zhenyuan zhang Min Gao College of Electrical Engineering and Control Science Nanjing Tech UniversityNanjing 211816China Research Institute of NARI Technology Co. Ltd.Nanjing 211106China School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Falcon Computing Solutions 10880 Wilshire Blvd Suite 1132Los AngelesCA 90024USA

An integrated energy system(IES)contributes to improving energy efficiency and promoting sustainable energy *** different dynamic characteristics of the system,such as demand/response schemes and complex coupling characteristics among energy sources,siting and sizing of multitype energy storage(MES)are very important for the economic operation of the *** the effect of the diversity of the IES on system reserve based on electricity,gas and heat systems in different scenarios,a two-stage MES optimal configuration model,considering the system reserve value,is *** the first stage,to determine the location and charging/discharging strategies,a location choice model that minimizes the operating cost,considering the system reserve value,is *** the second stage,a capacity choice model,to minimize the investment and maintenance cost of the MES,is ***,an example is provided to verify the effectiveness of the MES configuration method in this paper in handling operational diversity and ensuring system *** with the configuration method that disregards the system reserve value,the results show that the MES configuration method proposed in this paper can reduce the annual investment cost and operating cost and improve the system reserve value.

关键词： Integrated energy system multitype energy storage optimal configuration renewable source system reserve value

Deep reinforcement learning based active surge control for aeroengine compressors

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Chinese Journal of Aeronautics 2024年第7期37卷 418-438页

作者： Xinglong zhang Zhonglin LIN Runmin ji Tianhong zhang College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350108China

This study proposes an active surge control method based on deep reinforcement learning to ensure the stability of compressors when adhering to the pressure rise command across the wide operating range of an ***,the study establishes the compressor dynamic model with uncertainties,disturbances,and Close-Coupled Valve(CCV)actuator *** upon this foundation,a Partially Observable Markov Decision Process(POMDP)is defined to facilitate active surge *** address the issue of unobservability,a nonlinear state observer is designed using a finite-time high-order sliding ***,an Improved Soft Actor-Critic(ISAC)algorithm is developed,incorporating prioritized experience replay and adaptive temperature parameter techniques,to strike a balance between exploration and convergence during *** addition,reasonable observation variables,error-segmented reward functions,and random initialization of model parameters are employed to enhance the robustness and generalization ***,to assess the effectiveness of the proposed method,numerical simulations are conducted,and it is compared with the fuzzy adaptive backstepping method and Second-Order Sliding Mode Control(SOSMC)*** simulation results demonstrate that the deep reinforcement learning based controller outperforms other methods in both tracking accuracy and ***,the proposed active surge controller can effectively ensure stable operation of compressors in the high-pressure-ratio and high-efficiency region.

关键词： Aeroengine surge Active surge control Moore-Greitzer model Deep reinforcement learning Soft actor-critic Nonlinear observer

Genome-wide identification and characterization of the PbrATG family in Pyrus bretschneideri and functional analysis of PbrATG1a in response to Botryosphaeria dothidea

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Horticultural Plant Journal 2024年第2期10卷 327-340页

作者： Yun Wang xun Sun Zhenwu zhang Zhihua Xie Kaijie Qi Shaoling zhang Center of Pear Engineering Technology Research State Key Laboratory of Crop Genetics and Germplasm EnhancementCollege of HorticultureNanjing Agricultural UniversityNanjingJiangsu 210095China

The pear is an economic fruit that is widely planted around the world and is loved by people for its rich nutritional value. Autophagy is a self-protection mechanism in eukaryotes, and its occurrence often accompanied by the degradation of damaged substances in cells and the recycling of nutrients. Autophagy is one of the mechanisms through which plants respond to environmental stress and plays an important role in plant development and stress resistance. Functional studies of autophagy-related genes (ATGs) have been performed on a variety of plant species, but little information is available on the ATG family in pear (Pyrus bretschneideri Rehd). Therefore, we analyzed the evolutionary dynamics and performed a genome-wide characterization of the PbrATG gene family. A total of 28 PbrATG members were *** analysis showed that PbrATGs were more closely related to ATGs of European pear and apple. Evolutionary analysis revealed that whole-genome duplication (WGD) and dispersed duplication events were the main driving forces of PbrATG family *** analysis of different pear tissues showed that all the genes were expressed in different pear tissues, and different PbrATGs are expressed at different times and in different locations. Moreover, all PbrATGs also responded to different abiotic stresses, especially salt and drought stress, which elicited the highest expression levels. Pear seedlings were subsequently infected with Botryosphaeria dothidea (***). The results showed that different PbrATGs had different expression patterns at different infection stages. According to the gene expression data, PbrATG1a was selected as a key autophagy gene for further analysis. Silencing of PbrATG1a reduced the resistance of pear to B. dothidea, which resulted in increased lesions, reactive oxygen species (ROS) contents, antioxidant enzyme activity, and gene expression levels in the silenced pear seedlings after B. dothidea inoculation. In this s

关键词： Autophagy Pear PbrATGs Abiotic stress Botryosphaeria dothidea PbrATG1a

Hydrothermal carbonization pretreatment makes a remarkable difference in activation of rice and lettuce in food waste

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Green Chemical Engineering 2024年第3期5卷 348-363页

作者： Lijun zhang Yifan Sun Chao Li Shu zhang Mortaza Gholizadeh xun Hu School of Material Science and Engineering University of JinanJinan250022China Joint International Research Laboratory of Biomass Energy and Materials College of Materials Science and EngineeringNanjing Forestry UniversityNanjing210037China Faculty of Chemical and Petroleum Engineering University of TabrizTabrizIran

Cooked rice and the vegetables like lettuce are common kitchen waste,which are carbonaceous materials and have the potential as feedstock for the production of activated *** is similar to hydrothermal treatment(HTC),which might impact the subsequent activation of kitchen *** this study,the HTC of lettuce,rice,or their mixture and the activation of the resulting hydrochars were *** results indicated that cross-polymerization between the N-containing organics from lettuce and the sugar derivatives from rice took place in their co-HTC,which significantly increased the hydrochar *** of the hydrochar from the coHTC generated the AC with a yield of 2 times that from direct activation of mixed lettuce/***,the coHTC facilitated aromatization,reducing reactivity with K2C2O4in activation and producing the AC with main micropores and low specific surface *** of the hydrochar from HTC of rice followed the above trend,while that from lettuce was the *** organics in lettuce were thermally unstable and could not undergo sufficient *** activation of hydrochar from HTC of lettuce thus generated the AC with the lowest yield,but the highest specific surface area(1684.9 m2/g),abundant mesopores,and superior capability for adsorption of ***,the environmental impacts and energy consumption for the production of AC from the hydrochar of lettuce were higher than that from hydrochar of co-HTC.

关键词： Food waste Hydrothermal pretreatment Hydrochar Chemical activation Products properties

Microsnoop: A generalist tool for microscopy image representation

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The Innovation 2024年第1期5卷 109-117页

作者： Dejin xun Rui Wang Xingcai zhang Yi Wang Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China State Key Lab of Computer-Aided Design&Computer Graphics Zhejiang UniversityHangzhou 310058China John A.Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMA 02138USA Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University Hangzhou 310018China National Key Laboratory of Chinese Medicine Modernization Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxing 314100China

Accurate profiling of microscopy images from small scale to high throughput is an essential procedure in basic and applied biological ***,we present Microsnoop,a novel deep learning–based representation tool trained on large-scale microscopy images using masked self-supervised *** can process various complex and heterogeneous images,and we classified images into three categories:single-cell,full-field,and batch-experiment *** benchmark study on 10 high-quality evaluation datasets,containing over 2,230,000 images,demonstrated Microsnoop’s robust and state-ofthe-art microscopy image representation ability,surpassing existing generalist and even several custom *** can be integrated with other pipelines to perform tasks such as superresolution histopathology image and multimodal ***,Microsnoop can be adapted to various hardware and can be easily deployed on local or cloud computing *** will regularly retrain and reevaluate the model using communitycontributed data to consistently improve Microsnoop.

关键词： hardware image representation

Design and test of a double compression seeder for pre-sowing and seed furrow of wheat in wide-seedling belts

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International Journal of Agricultural and Biological Engineering 2024年第4期17卷 136-145页

作者： xun He Run zhang jingfeng zhang Yinghao Zhu Wanzhang Wang Hongmei zhang College of Mechanical and Electrical Engineering Henan Agricultural UniversityZhengzhou 450002China

To solve the problem of poor sowing quality due to loose soil in wheat seedbed after land preparation in the Huang-Huaihai region of China,a double compression seeder for pre-sowing and seed furrow of wheat in wide-seedling belts was *** machine sowing operation was divided into two processes:pre-sowing compression and seed ditch compression,pre-sowing compression was carried out homogenization of the pre-sowing seed bed that the tractor wheel has crushed,and the seed ditch compression compresses the seeds and soil in the seed ditch,so that the seeds were embedded in the seed ditch *** analyzing the kinematics of the pre-planting compression device and the spiral blade in the process of soil levelling and compression,the structure of the equal-difference variable-diameter equal-pitch spiral conveying winch was designed,and the key parameters of the drum spiral blade were determined,and then the height of the spiral blades,the rutting distance and the speed of the compression roller were taken as the test factors,and the soil flatness was used as the index to carry out the discrete element simulation *** simulation results show that when the spiral blade was 4.85 cm,the rut distance was 37.4 cm,and the rotation speed was 327.16 r/min,the optimal land flatness was ***,field experiments were carried out on the seeder,and the results showed that:the soil bulk density after operation was 22.7%greater than that before sowing(p<0.01),and the soil flatness was 1.9 cm,which was consistent with the simulated *** use of pre-sowing compression and seed furrow compression methods improved the soil environment of the seed bed,increased the uniformity of the seeding depth,and promoted the root growth of *** study provides equipment support and technical reference for agricultural production in wheat-corn rotation areas in the Huang-Huaihai region of China.

关键词： wheat seeding quality pre-sowing compression seed furrow compression field experiment

Constructing high coordination number of Ir-O-Ru bonds in IrRuO_(x)nanomeshes for highly stable acidic oxygen evolution reaction

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Nano Research 2024年第6期17卷 5073-5079页

作者： Ge Yu Ruilong Li Yida zhang Xingen Lin Gongming Wang xun Hong Center of Advanced Nanocatalysis(CAN) Department of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026China National Synchrotron Radiation Laboratory(NSRL) University of Science and Technology of ChinaHefei 230029China

IrRu bimetallic oxides are recognized as the promising acidic oxygen evolution reaction(OER)catalysts,but breaking the trade-off between their activity and stability is an unresolved ***,addressing the issues of mass transport obstruction of IrRu bimetallic oxides under high current remains a challenge for the development of proton exchange membrane water electrolysis(PEM-WE).Herein,we prepared an IrRuO_(x)nanomeshes(IrRuO_(x)NMs)with high coordination number(CN)of Ir-O-Ru bonds in a mixed molten salt with high solubility of the Ir/Ru precursor.X-ray absorption spectroscopy analysis revealed that the IrRuO_(x)NMs possess high coordination number of Ir-O-Ru bonds(CNIr-O-Ru=5.6)with a distance of 3.18Å.Moreover,the nanomesh structures of IrRuO_(x)NMs provided hierarchical channels to accelerate the transport of oxygen and water,thus further improving the electrochemical ***,the IrRuO_(x)NMs as OER catalysts can simultaneously achieve high activity and stability with low overpotential of 196 mV to reach 10 mA·cm^(−2)and slightly increase by 70 mV over 650 h *** electrochemical mass spectrometry tests suggest that the preferred OER mechanism for IrRuO_(x)NMs is the adsorbent evolution mechanism,which is beneficial for the robust structural stability.

关键词： oxygen evolution reaction IrRuO_(x) Ir-O-Ru bonds two-dimensional(2D)nanomesh proton exchange membrane device mass transport