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面向检修的水电设备数字化建模

电力系统自动化 2005年第7期29卷 79-83页

作者：陈燚涛李朝晖华中科技大学水电与数字化工程学院湖北省武汉市430074

针对水电设备状态检修的需求,在三维动态仿真技术的基础上提出了设备数字化建模的方法。该方法将对象设备的可视化模型和数字特性模型有机地结合起来,使得数字化模型能自动识别设备状态,全面反映设备的运行状态和健康状态,为设备故障诊... 详细信息

针对水电设备状态检修的需求,在三维动态仿真技术的基础上提出了设备数字化建模的方法。该方法将对象设备的可视化模型和数字特性模型有机地结合起来,使得数字化模型能自动识别设备状态,全面反映设备的运行状态和健康状态,为设备故障诊断打下基础。文中给出了水轮发电机组摇摆式导叶主接力器的数字化模型建模及应用实例。

关键词：水电设备状态检修数字化建模

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Robust cooperative multi-agent reinforcement learning via multi-view message certification

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Science China(Information Sciences) 2024年第4期67卷 131-145页

作者： Lei YUAN tao JIANG Lihe LI Feng chen Zongzhang ZHANG Yang YU National Key Laboratory for Novel Software Technology Nanjing University Polixir Technologies

Many multi-agent scenarios require message sharing among agents to promote coordination,hastening the robustness of multi-agent communication when policies are deployed in a message perturbation environment. Major relevant studies tackle this issue under specific assumptions, like a limited number of message channels would sustain perturbations, limiting the efficiency in complex scenarios. In this paper,we take a further step in addressing this issue by learning a robust cooperative multi-agent reinforcement learning via multi-view message certification, dubbed CroMAC. Agents trained under CroMAC can obtain guaranteed lower bounds on state-action values to identify and choose the optimal action under a worst-case deviation when the received messages are perturbed. Concretely, we first model multi-agent communication as a multi-view problem, where every message stands for a view of the state. Then we extract a certificated joint message representation by a multi-view variational autoencoder(MVAE) that uses a product-of-experts inference network. For the optimization phase, we do perturbations in the latent space of the state for a certificate guarantee. Then the learned joint message representation is used to approximate the certificated state representation during training. Extensive experiments in several cooperative multi-agent benchmarks validate the effectiveness of the proposed CroMAC.

关键词： multi-agent reinforcement learning robust communication adversarial training multi-view learning message certification

A state of art review on time series forecasting with machine learning for environmental parameters in agricultural greenhouses

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Information Processing in Agriculture 2024年第2期11卷 143-162页

作者： Gedi Liu Keyang Zhong Huilin Li tao chen Yang Wang National Innovation Center for Digital Fishery China Agricultural University100083 BeijingChina Key Laboratory of Smart Farming Technologies for Aquatic Animal and Livestock Ministry of Agriculture and Rural AffairsChina Agricultural University100083 BeijingChina Beijing Engineering and Technology Research Center for Internet of Things in Agriculture China Agricultural University100083 BeijingChina College of Information and Electrical Engineering China Agricultural University100083 BeijingChina Department of Chemical and Process Engineering University of SurreyGU27XH GuildfordUnited Kingdom

Agricultural greenhouse production has to require a stable and acceptable environment,it is therefore essential for future greenhouse production to obtain full and precisely internal dynamic environment *** modeling based on machine learning methods,e.g.,intelligent time series prediction modeling,is a popular and suitable way to solve the above *** this article,a systematic literature review on applying advanced time series models has been systematically conducted via a detailed analysis and evaluation of 61 pieces selected from 221 *** historical process of time series model application from the use of data and information strategies was first ***,the accuracy and generalization of the model from the selection of model parameters and time steps,providing a new perspective for model development in this field,were compared and ***,the systematic review results demonstrate that,compared with traditional models,deep neural networks could increase data structure mining capabilities and overall information simulation capabilities through innovative and effective structures,thereby it could also broaden the selection range of environmental parameters for agricultural facilities and achieve environmental prediction end-to-end optimization via intelligent time series model based on deep neural networks.

关键词： Horticultural greenhouse environment Time series algorithms Prediction Deep neural networks

Preliminary exploration of animal models of congenital choledochal cysts

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World Journal of Gastroenterology 2024年第10期30卷 1420-1430页

作者： Shu-Hao Zhang Yue-Bin Zhang Duo-Te Cai tao Pan Ken chen yi Jin Wen-Juan Luo Zong-Wei Huang Qing-Jiang chen Zhi-Gang Gao Department of General Surgery Children’s HospitalZhejiang University School of MedicineHangzhou 310000Zhejiang ProvinceChina

BACKGROUND Various animal models have been used to explore the pathogenesis of choledochal cysts(CCs),but with little convincing *** surgical techniques can achieve satisfactory outcomes for treatment of ***,recent studies have focused more on clinical issues rather than basic ***,we need appropriate animal models to further basic *** To establish an appropriate animal model that may contribute to the investigation of the pathogenesis of *** Eighty-four specific pathogen-free female Sprague-Dawley rats were randomly allocated to a surgical group,sham surgical group,or control group.A rat model of CC was established by partial ligation of the bile *** reliability of the model was confirmed by measurements of serum biochemical indices,morpho-logy of common bile ducts of the rats as well as molecular biology experiments in rat and human *** Dilation classified as mild(diameter,≥1 mm to<3 mm),moderate(≥3 mm to<10 mm),and severe(≥10 mm)was observed in 17,17,and 2 rats in the surgical group,respectively,while no dilation was observed in the control and sham surgical *** levels of alanine aminotransferase,aspartate aminotrans-ferase,total bilirubin,direct bilirubin,and total bile acids were significantly elevated in the surgical group as compared to the control group 7 d after surgery,while direct bilirubin,total bilirubin,and gamma-glutamyltransferase were further increased 14 d after *** of the biochemical indices gradually decreased to normal ranges 28 d after *** protein expression trend of signal transducer and activator of transcription 3 in rat model was consistent with the human CC *** The model of partial ligation of the bile duct of juvenile rats could morphologically simulate the cystic or fusiform CC,which may contribute to investigating the pathogenesis of CC.

关键词： Choledochal cyst Animal model Partial ligation Cystic and fusiform dilation Juvenile rats

Enhancing the electrochemical performance of Na metal anodes via local eutectic melting in porous Al-Cu alloy hosts

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Nano Research 2024年第7期17卷 6111-6118页

作者： tao Hu Qiang Wu cheng Wang Jialu chen Fu Su Zibo chen yizhou Wang Jianyu chen Yanwen Ma Jin Zhao State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced Materials(IAM) Nanjing University of Posts&Telecommunications9 Wenyuan RoadNanjing 210023China Materials Science and Engineering King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia Suzhou Vocational Institute of Industrial Technology 1 Zhineng AvenueSuzhou International Education ParkSuzhou 215104China

Sodium(Na)metal batteries(SMBs)have emerged as promising alternatives to lithium metal batteries for large-scale energy storage applications,owing to their cost-effectiveness,abundance,and favorable redox ***,the practical implementation of SMBs faces several challenges associated with the Na metal anode,including the formation of dendrites,low Coulombic efficiency,and capacity ***,we propose a novel approach to enhance the electrochemical performance of Na metal anodes through a porous Al-Cu alloy host(PAC)fabricated by a local eutectic melting *** local eutectic melting facilitates the development of a conductive network,offering mechanical support,and the porous structure provides abundant channels for the diffusion of Na ions and accommodates volume fluctuations in the Na metal during charge–discharge ***,the PAC exhibits a high average Coulombic efficiency of 99.8%at 1 mA·cm^(−2)for 1 mAh·cm^(−2)and a low voltage polarization of 19 mV during 500 *** study provides valuable insight into the design and fabrication of highperformance Na metal anodes,which hold significant promise for the advancements of next-generation energy storage systems.

关键词： Na metal anode porous Al-Cu alloy porous current collector local eutectic melting

Pericytes protect rats and mice from sepsis-induced injuries by maintaining vascular reactivity and barrier function:implication of miRNAs and microvesicles

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Military Medical Research 2024年第1期11卷 1-18页

作者： Zi-Sen Zhang yi-Yan Liu Shuang-Shuang He Dai-Qin Bao Hong-chen Wang Jie Zhang Xiao-Yong Peng Jia-tao Zang Yu Zhu Yue Wu Qing-Hui Li tao Li Liang-Ming Liu State Key Laboratory of Trauma Burns and Combined InjuryDepartment of Shock and TransfusionResearch Institute of SurgeryDaping HospitalArmy Medical UniversityChongqing 400042China

Background Vascular hyporeactivity and leakage are key pathophysiologic features that produce multi-organ damage upon *** hypothesized that pericytes,a group of pluripotent cells that maintain vascular integrity and tension,are protective against sepsis via regulating vascular reactivity and *** We conducted a series of in vivo experiments using wild-type(WT),platelet-derived growth factor receptor-β(PDGFR-β)-Cre+mT/mG transgenic mice and Tie2-Cre+Cx43^(flox/flox)mice to examine the relative contribution of pericytes in sepsis,either induced by cecal ligation and puncture(CLP)or lipopolysaccharide(LPS)*** a separate set of experiments with Sprague-Dawley(SD)rats,pericytes were depleted using CP-673451,a selective PDGFR-βinhibitor,at a dosage of 40 mg/(kg·d)for 7 consecutive *** pericytes,vascular endothelial cells(VECs)and vascular smooth muscle cells(VSMCs)were used for mechanistic *** effects of pericytes and pericyte-derived microvesicles(PCMVs)and candidate miRNAs on vascular reactivity and barrier function were also *** CLP and LPS induced severe injury/loss of pericytes,vascular hyporeactivity and leakage(P<0.05).Transplantation with exogenous pericytes protected vascular reactivity and barrier function via microvessel colonization(P<0.05).Cx43 knockout in either pericytes or VECs reduced pericyte colonization in microvessels(P<0.05).Additionally,PCMVs transferred miR-145 and miR-132 to VSMCs and VECs,respectively,exerting a protective effect on vascular reactivity and barrier function after sepsis(P<0.05).miR-145 primarily improved the contractile response of VSMCs by activating the sphingosine kinase 2(Sphk2)/sphingosine-1-phosphate receptor(S1PR)1/phosphorylation of myosin light chain 20 pathway,whereas miR-132 effectively improved the barrier function of VECs by activating the Sphk2/S1PR2/zonula occludens-1 and vascular endothelial-cadherin *** Pericytes are protective a

关键词： Pericyte Vascular reactivity Vascular permeability Cx43 Microvesicle

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Transparent micropatterned conductive films based on highlyordered nanowire network

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Nano Research 2024年第5期17卷 4288-4297页

作者： Xin-Ran Zhang Hai-tao Deng Xu Zeng yi-Lin Wang Peng Huang Xiao-Sheng Zhang School of Integrated Circuit Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

Transparent conductive films that are based on nanowire networks are essential to construct flexible,wearable,and even stretchable ***,large-scale precise micropatterning,especially with regard to the controllability of the organizing orientation of nanowires,is a critical ***,we proposed a liquid film rupture self-assembly approach for manufacturing transparent conductive films with microstructure arrays based on a highly ordered nanowire *** large-scale microstructure conductive films were fabricated through air-liquid interface self-assembly and liquid film rupture *** typical micropattern morphologies,including square,hexagon,circle,serpentine,etc.,were prepared to reveal the universal applicability of the proposed *** homogeneity and controllability of this approach were verified for multiple *** the assembly cycles increasing,the optical transmittance decreases *** addition,theoretical model analysis is carried out,and the analytical formula of the speed of the film moving with the surface tension and the density of the liquid film is ***,the feasibility of this approach for piezoresistive strain sensors is *** fabrication approach demonstrated a cost-effective and efficient method for precisely arranging nanowires,which is useful in transparent and wearable applications.

关键词： flexible electronics transparent conductive network micropatterning nanowires micro electromechanical systems(MEMS)

Allelic reprogramming of chromatin states in human early embryos

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National Science Review 2024年第03期11卷 58-71页

作者： Shenli Yuan Lei Gao Wenrong tao Jianhong Zhan Gang Lu Jingye Zhang Chuanxin Zhang Lizhi yi Zhenbo Liu Zhenzhen Hou Min Dai Han Zhao Zi-Jiang chen Jiang Liu Keliang Wu Center for Reproductive Medicine Shandong University CAS Key Laboratory of Genome Sciences and Information Collaborative Innovation Center of Genetics and Development Beijing Institute of Genomicsand China National Center for BioinformationChinese Academy of Sciences University of Chinese Academy of Sciences CUHK-SDU Joint Laboratory on Reproductive Genetics School of Biomedical Sciences the Chinese University of Hong Kong Key Laboratory of Reproductive Endocrinology of the Ministry of Education Shandong University Center for Reproductive Medicine Ren Ji Hospital School of Medicine Shanghai Jiao Tong University CAS Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences

The reprogramming of parental epigenomes in human early embryos remains elusive. To what extent the characteristics of parental epigenomes are conserved between humans and mice is currently unknown. Here,we mapped parental haploid epigenomes using human parthenogenetic and androgenetic embryos. Human embryos have a larger portion of genome with parentally specific epigenetic states than mouse *** allelic patterns of epigenetic states for orthologous regions are not conserved between humans and mice. Nevertheless, it is conserved that maternal DNA methylation and paternal H3K27me3 are associated with the repression of two alleles in humans and mice. In addition, for DNA-methylation-dependent imprinting, we report 19 novel imprinted genes and their associated germline differentially methylated regions. Unlike in mice, H3K27me3-dependent imprinting is not observed in human early ***, allele-specific epigenomic reprogramming is different in humans and mice.

关键词： human embryo epigenetics reprogramming DNA methylation H3K27me3 chromatin accessibility

Stable carbon isotope composition and intrinsic water use efficiency in plants along an altitudinal gradient on the eastern slope of Yulong Snow Mountain, China

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Ecological Processes 2024年第2期13卷 218-230页

作者： Feng Jiang tao Pu Zi-Jing Xue Yan-Wei Ma Xiao-yi Shi Fu-Xi Shi College of Geography and Environmental Sciences Zhejiang Normal University Yulong Snow Mountain Glacier and Environment Observation and Research Station/State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences Key Laboratory of National Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed College of Forestry Jiangxi Agricultural University

Background Stable carbon isotope composition(δ13Cp) can be used to estimate the changes in intrinsic water use efficiency（iWUE） in plants,which helps us to better understand plants' response strategies to climate *** study focused on the variations in δ13Cpand iWUE for the different life-form plants（i.e.,herbs,shrubs,and trees）along an altitudinal gradient（3300,3600,3900,4100,4300,and 4500 m） on the eastern slope of Yulong Snow Mountain,southeastern margin of the Qinghai-Tibet *** response mechanisms of δ13Cpand iWUE for different life-form plants to altitude were thoroughly analyzed in this mountain *** The δ13Cpvalues of plants on the eastern slopes of Yulong Snow Mountain ranged from-30.4‰to-26.55‰,with a mean of-28.02‰,indicating a dominance of *** δ13Cpand iWUE values varied among different life-form plants in the order of herbs> shrubs> trees,particularly in 3600,3900,and 4300 ***δ13Cpand iWUE values for herbs and shrubs increased with altitude and were mainly controlled by air *** two parameters for trees exhibited a trend of initial decrease followed by an increase with *** 3900 m,the δ13Cpand iWUE values decreased with altitude,influenced by soil ***,above 3900 m,the two parameters increased with altitude,mainly regulated by air *** addition,iWUE was positively correlated with leaf P content but negatively correlated with leaf N:P ratio,especially for herbs and trees,suggesting that P plays a key role in modulating iWUE in this *** The diffe rentiated responses of water availability for different life-form plants to a higher altitudinal gradient are regulated by air temperature,soil moisture,and leaf P content in the Yulong Snow *** results provide valuable insights into understanding the wate r-carbon relationships in high-altitude ecosystems.

关键词： Stable carbon isotope Water use efficiency Altitude Life form Yulong Snow Mountain