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National Science Review 2024年第4期11卷 130-140页

作者： Huimin Wang Zhe-ning Chen Yuanyuan Wang Dongshuang Wu Minna cao Fanfei Sun Rong cao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences School of Materials Science and Engineering Nanyang Technological University Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied Physics Chinese Academy of Sciences Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China

The absence of efficient and durable catalysts for oxygen evolution reaction（OER） is the main obstacle to hydrogen production through water splitting in an acidic ele ***,we report a controllable synthesis method of surface IrOxwith changing Au/Ir compositions by constructing a range of sub-10-nm-sized core-shell nanocatalysts composed of an Au core and AuxIr1-xalloy *** particular,Au@Au0.43Ir0.57exhibits 4.5 times higher intrinsic OER activity than that of the commercial Ir/*** X-ray-based spectroscopies,electron microscopy and density functional theory calculations revealed a balanced binding of reaction intermediates with enhanced *** water-splitting cell using a load of 0.02 mgIr/cm2of Au@Au0.43Ir0.57as both anode and cathode can reach 10 mA/cm2at 1.52 V and maintain activity for at least194 h,which is better than the cell using the commercial couple Ir/C‖Pt/C（1.63 V,0.2 h）.

关键词： controllable synthesis of surface IrOx oxygen evolution reaction acidic water splitting catalytic stability transition metal catalysts

Superior efficiency and stability of YbO_(x)-enhanced perovskite solar cells

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Science China Materials 2024年第4期67卷 1356-1358页

作者： Qifeng Zhang Guozhong cao Department of Electrical and Computer Engineering North Dakota State UniversityFargoND 58108-6050USA Department of Materials Science and Engineering University of WashingtonSeattleWA 98195-2120USA

Perovskite solar cells represent a revolutionary class of photovoltaic devices that have gained substantial attention for their exceptional performance and potential to provide an affordable and efficient solution for harnessing solar energy. These cells utilize perovskite-structured materials, typically hybrid organicinorganic lead halide compounds, as the light-absorbing layer.

关键词： energy perovskite stability

Novel method for extraction of ship target with overlaps in SAR image via EM algorithm

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Journal of Systems Engineering and Electronics 2024年第4期35卷 874-887页

作者： cao Rui WANG Yong School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China

The quality of synthetic aperture radar(SAR)image degrades in the case of multiple imaging projection planes(IPPs)and multiple overlapping ship targets,and then the performance of target classification and recognition can be *** addressing this issue,a method for extracting ship targets with overlaps via the expectation maximization(EM)algorithm is ***,the scatterers of ship targets are obtained via the target detection ***,the EM algorithm is applied to extract the scatterers of a single ship target with a single ***,a novel image amplitude estimation approach is pro-posed,with which the radar image of a single target with a sin-gle IPP can be *** proposed method can accom-plish IPP selection and targets separation in the image domain,which can improve the image quality and reserve the target information most *** of simulated and real mea-sured data demonstrate the effectiveness of the proposed method.

关键词： expectation maximization(EM)algorithm image processing imaging projection plane(IPP) overlapping ship tar-get synthetic aperture radar(SAR)

Estimated Human Papillomavirus Vaccine Coverage Among Females 9-45 Years of Age — China, 2017-2022

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China CDC weekly 2024年第19期6卷 413-417页

作者： Junlei Chen Zhaonan Zhang Weiyi Pan Yifan song Lu Zheng Li Li Jiakai Ye Lei cao Wenzhou Yu Fujian Center for Disease Control and Prevention Fuzhou CityFujian ProvinceChina National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases(NITFID) BeijingChina National Immunization Program Chinese Center for Disease Control and PreventionBeijingChina Jining Center for Disease Control and Prevention Jining CityShandong ProvinceChina

Summary What is already known on this topic?There is a lack of comprehensive data on the coverage of the human papillomavirus(HPV)vaccine in *** limited published literature hampers our ability to accurately assess th... 详细信息

关键词： vaccine Vaccine China.

MetaPINNs:Predicting soliton and rogue wave of nonlinear PDEs via the improved physics-informed neural networks based on meta-learned optimization

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Chinese Physics B 2024年第2期33卷 96-107页

作者：郭亚楠曹小群宋君强冷洪泽 College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China College of Computer National University of Defense TechnologyChangsha 410073China Naval Aviation University Huludao 125001China

Efficiently solving partial differential equations(PDEs)is a long-standing challenge in mathematics and physics *** recent years,the rapid development of artificial intelligence technology has brought deep learning-based methods to the forefront of research on numerical methods for partial differential *** them,physics-informed neural networks(PINNs)are a new class of deep learning methods that show great potential in solving PDEs and predicting complex physical *** the field of nonlinear science,solitary waves and rogue waves have been important research *** this paper,we propose an improved PINN that enhances the physical constraints of the neural network model by adding gradient information *** addition,we employ meta-learning optimization to speed up the training *** apply the improved PINNs to the numerical simulation and prediction of solitary and rogue *** evaluate the accuracy of the prediction results by error *** experimental results show that the improved PINNs can make more accurate predictions in less time than that of the original PINNs.

关键词： physics-informed neural networks gradient-enhanced loss function meta-learned optimization nonlinear science

Distributed Heterogeneous Multi-Agent Optimization with Stochastic Sub-Gradient

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Journal of Systems Science & Complexity 2024年第4期37卷 1470-1487页

作者： HU Haokun MO Lipo cao Xianbing School of Mathematics and Statistics Central South UniversityChangsha 410083China School of Mathematics and Statistics Beijing Technology and Business UniversityBeijing 100048China Research Centre for Agri-Product Quality Traceability Beijing Technology and Business UniversityBeijing 100048China School of Computer and Artificial Intelligence Beijing Technology and Business UniversityBeijing 100048China China Food Flavor and Nutrition Health Innovation Center Beijing Technology and Business UniversityBeijing 100048China

This paper studies the optimization problem of heterogeneous networks under a timevarying *** agent only accesses to one local objective function,which is *** improved algorithm with noisy measurement of local objective functions' sub-gradients and additive noises among information exchanging between each pair of agents is designed to minimize the sum of objective functions of all *** weaken the effect of these noises,two step sizes are introduced in the control *** graph theory,stochastic analysis and martingale convergence theory,it is proved that if the sub-gradients are uniformly bounded,the sequence of digraphs is balanced and the union graph of all digraphs is joint strongly connected,then the designed control protocol can force all agents to find the global optimal point almost *** last,the authors give some numerical examples to verify the effectiveness of the stochastic sub-gradient algorithms.

关键词： Communication noises distributed stochastic optimization heterogeneous networks subgradient measurement noises

Fatigue-resistant Hydrogels

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Chemical Research in Chinese Universities 2024年第1期40卷 64-77页

作者： LI Luofei LEI Hai cao Yi Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State MicrostructureDepartment of PhysicsNanjing UniversityNanjing 210093P.R.China Department of Physics Zhejiang UniversityHangzhou 310027P.R.China

Hydrogels have been extensively studied for applications in various fields, such as tissue engineering and soft robotics, as determined by their mechanical properties. The mechanical design of hydrogels typically focuses on the modulus, toughness, and deformability. These characteristics play important roles and make great achievements for hydrogel use. In recent years, a growing body of research has concentrated on the fatigue property of hydrogels, which determines their resistance to crack propagation in the networks during cyclic mechanical loads for applications. However, knowledge of hydrogel fatigue behavior remains notably deficient. Here, we present a brief overview of the fatigue behavior of hydrogels, encompassing the general experimental methods to measure the fatigue property and fundamental theoretical calculation models. Then, we highlight multiple strategies to enhance the fatigue resistance of hydrogels. Finally, we present our perspectives on fatigue-resistant hydrogels, outstanding challenges and potential directions for future research.

关键词： Hydrogel Fatigue-resistant Fracture

Grassland-type ecosystem stability in China differs under the influence of drought and wet events

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Journal of Arid Land 2024年第5期16卷 615-631页

作者： cao Wenyu BAI Jianjun YU Leshan School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China International Business School Shaanxi Normal UniversityXi'an 710119China

Ecological stability is a core issue in ecological research and holds significant implications forhumanity. The increased frequency and intensity of drought and wet climate events resulting from climatechange pose a major threat to global ecological stability. Variations in stability among different ecosystemshave been confirmed, but it remains unclear whether there are differences in stability within the sameterrestrial vegetation ecosystem under the influence of climate events in different directions and ***'s grassland ecosystem includes most grassland types and is a good choice for studying this *** study used the Standardized Precipitation Evapotranspiration Index-12 (SPEI-12) to identify thedirections and intensities of different types of climate events, and based on Normalized DifferenceVegetation Index (NDVI), calculated the resistance and resilience of different grassland types for 30consecutive years from 1990 to 2019 (resistance and resilience are important indicators to measurestability). Based on a traditional regression model, standardized methods were integrated to analyze theimpacts of the intensity and duration of drought and wet events on vegetation stability. The resultsshowed that meadow steppe exhibited the highest stability, while alpine steppe and desert steppe had thelowest overall stability. The stability of typical steppe, alpine meadow, temperate meadow was at anintermediate level. Regarding the impact of the duration and intensity of climate events on vegetationecosystem stability for the same grassland type, the resilience of desert steppe during drought was mainlyaffected by the duration. In contrast, the impact of intensity was not significant. However, alpine steppewas mainly affected by intensity in wet environments, and duration had no significant impact. Ourconclusions can provide decision support for the future grassland ecosystem governance.

关键词： grassland ecosystem stability resistance resilience different climate types drought climate event wet climate event

Accuracy of numerical relativity waveforms with respect to space-based gravitational wave detectors

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Communications in Theoretical Physics 2024年第1期76卷 82-95页

作者： Zun Wang Junjie Zhao Zhoujian cao Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Astronomy Beijing Normal UniversityBeijing 100875China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China

As with the laser interferometer gravitational-wave observatory(LIGO),the matched filtering technique will be critical to the data analysis of gravitational wave detection by space-based detectors,including LISA,Taiji and *** templates are the basis for such matched filtering *** construct ready-to-use waveform templates,numerical relativity waveforms are a starting ***,the accuracy issue of numerical relativity waveforms is critically *** are many investigations regarding this issue with respect to *** unfortunately there are few results on this issue with respect to space-based *** current paper investigates this *** results indicate that the existing numerical relativity waveforms are as accurate as 99%with respect to space-based detectors,including LISA,Taiji and *** an accuracy level is comparable to that with respect to LIGO.

关键词： numerical relativity gravitational wave binary black hole

Dynamic impact properties of deep sandstone under thermal-hydraulicmechanical coupling loads

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Journal of Mountain Science 2024年第6期21卷 2113-2129页

作者： cao Chunhui DING Haonan ZOU Baoping School of Civil Engineering and Architecture Zhejiang University of Science and TechnologyHangzhou 310023China Zhejiang-Singapore Joint Laboratory for Urban Renewal and Future City Hangzhou 310023China

The deep rock mass within coal mines situated in a challenging environment are characterized by high ground stress,high geotemperature,high osmotic water pressure,and dynamic disturbances from mechanical *** investigate the impact of this complex mechanical environment on the dynamic characteristics of roof sandstone in self-formed roadways without coal pillars,standard specimens of deep sandstone from the 2611 upper tunnel working face of the Yongmei Company within the Henan Coal Chemical Industry Group in Henan,China were prepared,and an orthogonal test was *** a self-developed geotechnical dynamic impact mechanics test system,triaxial dynamic impact tests under thermal-hydraulicmechanical coupling conditions were conducted on deep *** results indicate that under high confining pressure,deep sandstone exhibits pronounced brittle failure at low temperatures,with peak strength gradually decreasing as temperature and osmotic water pressure ***,under low confining pressure and low temperature,the brittleness of deep sandstone weakens gradually,while ductility ***,sandstone demonstrates higher peak strength at low temperatures under high axial pressure conditions,lower peak strength at high temperatures,and greater strain under low axial pressure and high osmotic water *** in impact air pressure and osmotic water pressure have proportionally greater effects on peak stress and peak *** 50%of the input strain energy is utilized as effective energy driving the sandstone fracture *** analysis identifies the optimal combination of factors affecting the peak stress and peak strain of *** the coupling effect,intergranular and transgranular fractures occur within the *** images illustrate that the damage forms range from minor damage with multiple fissures to extensive fractures and severe *** study elucidates the varied dynamic impact me

关键词： Deep sandstone Thermal-hydraulicmechanical coupling Dynamic impact Stress-strain Failure Modes Polar analysis