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Explore the relationship between Bowen ratio and evapotranspiration in wetlands using the maximum entropy production model

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Journal of Hydrology 2025年 661卷

作者： Huaiwei Sun Leying Fu Weiguang Wang Jie Xue Jing Wang Weihong Liao Haicheng Li Xunlai Sun Yong Yang Jingfeng Wang Hong Zhang Fulong Chen Qiming Zheng Changqing Meng Wenxin Zhang School of Civil and Hydraulic Engineering Huazhong University of Science and Technology Wuhan 430074 China College of Water Conservancy & Architectural Engineering Shihezi University 832003 China Hubei Key Laboratory of Digital River Basin Science and Technology Huazhong University of Science and Technology Wuhan 430074 China Institute of Water Resources and Hydropower Huazhong University of Science and Technology Wuhan 430074 China College of Hydrology and Water Resources Hohai University Nanjing 210098 China State Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Hubei Water Resources Institude Wuhan 430070 China China Institute of Water Resource and Hydropower Research Beijing 100038 China School of Civil and Environmental Engineering Georgia Institute of Technology Atlanta 30318 USA School of Engineering and Built Environment Griffith University Australia Department of Geography and Resource Management The Chinese University of Hong Kong Hong Kong China School of Hydraulic Engineering North China Electric Power University Beijing China School of Geographical and Earth Sciences University of Glasgow Glasgow G12 8QQ UK

Wetlands play a critical role in the global water cycle and ecological health. However, understanding and accurately parameterizing water and heat exchanges in these areas is challenging due to the heterogeneous nature of wetland surfaces. This study extends the maximum entropy production (MEP) model to simulate wetland evapotranspiration (ET) by integrating NDVI dynamics, water evaporation, and plant transpiration. The model was applied to six FLUXNET wetland sites, with observation periods ranging from 1 to 8 years at daily temporal resolution. Across all time scales, the Nash-Sutcliffe Efficiency (NSE) improved by up to + 0.30 compared to the original model, with NSE values ranging from 0.67 to 0.83 and coefficients of determination (R2) between 0.80 and 0.97. Additionally, the root mean square error (RMSE) was reduced to as low as 7.61 W·m −2 for monthly estimates. These results demonstrate the enhanced model’s ability to capture the temporal dynamics of ET more accurately. Furthermore, the analysis revealed significant correlations between wetland vegetation, the Bowen ratio, and the transpiration-to-evapotranspiration ratio. To further quantify the contributions of multiple environmental factors to wetland energy flux distribution, a structural equation modeling (SEM) approach was employed. The SEM analysis confirms that vegetation exerts an important influence, while other variables such as temperature and radiation also significantly affect the partitioning between latent and sensible heat fluxes. These findings improve the understanding of wetland ET dynamics and provide a foundation for further exploration of the relationship between NDVI and energy flux partitioning.

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Online transmission policy in wireless powered networks with urgency-aware age of information 15

Online transmission policy in wireless powered networks with...

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15th IEEE International Wireless Communications and Mobile Computing Conference, IWCMC 2019

作者： Lu, Yang Xiong, Ke Fan, Pingyi Zhong, Zhangdui Letaief, Khaled Ben School of Computer and Information Technology Beijing Jiaotong University Beijing100044 China Beijing Key Laboratory of Traffic Data Analysis and Mining Beijing Jiaotong University Beijing100044 China Department of Electronic Engineering Tsinghua University Beijing100084 China State Key Lab of Rail Traffic Control and Safety Beijing Jiaotong University Beijing100044 China Beijing Engineering Research Center of High-speed Railway Broadband Mobile Communications Beijing Jiaotong University Beijing100044 China Hong Kong University of Science and Technology Hong Kong Hong Kong

ISBN: (纸本)9781538677476

This paper investigates the age of information (AoI) for a radio frequency (RF) energy harvesting (EH) enabled network, where a sensor first scavenges energy from a wireless power station and then transmits the collected status update to a sink node. To capture the thirst for the fresh update becoming more and more urgent as time elapsing, urgency-aware AoI (U-AoI) is defined, which increases exponentially with the increment of time between two received updates. Due to EH, a waiting time is required at the sensor before transmitting the status update. An optimization problem is formulated to minimize the long-term average U-AoI under constraint of energy causality. A two-layer algorithm is presented to solve it, where the outer loop is designed based on Dinklebach's method, and the inner loop presents a semi-closed-form expression of the optimal waiting time policy based on Karush-Kuhn-Tucker (KKT) optimality conditions. Numerical results show that our proposed optimal transmission policy outperforms the zero time waiting policy and equal time waiting policy in terms of long-term average U-AoI, especially when the networks are in slight load. It also shows that the system U-AoI first decreases and then keeps unchanged with the increments of EH circuit's saturation level. © 2019 IEEE.

关键词： Energy harvesting

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Effects of gold core size on regulating the performance of doxorubicin-conjugated gold nanoparticles

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Nano Research 2018年第6期11卷 3396-3410页

作者： Dongyan Wu Huaisong Wang Xiaoshuang Hou Huan Chen Yu Ma Yanglong Hou Jin Hong Ya Ding State Key Laboratory of Natural Medicines Department of Pharmaceutical Analysis China Pharmaceutical University Nanjing 210009 China Department of Biochemistry School of Life Science and Technology China Pharmaceutical University Nanjing 210009 China Beijing Key Laboratory for Magnetoelectric Materials and Devices (BKLMMD) Beijing Innovation Center for Engineering Science and Advanced Technology (BIC-ESAT) Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China Key Laboratory of Biomedical Functional Materials School of Sciences China Pharmaceutical University Nanjing 210009 China

Studies on the influence of one critical parameter （e.g., size）, targeting a specific disease, while keeping other factors unchanged, are important for improving understanding and application of the molecular design of biomedical nanomaterials. In this study, we used doxorubicin （Dox）-conjugated gold nanoparticles （GNPs） to investigate the effects of the size of the gold core （10, 20, or 60 nm） on the performance of their conjugates. We found that all three conjugates differed slightly in their physicochemical properties, facilitating a direct and accurate assessment of the size effects of GNP-Dox conjugates on their in vitro and in vivo performance. The cytological properties （the cell penetration rate and efficiency, as well as the cytotoxicity） and antitumor performance （the intratumoral penetration, treatment efficacy, and biodistribution） were highly correlated to the size of the inorganic core. Among all test groups, although the conjugate with a 60-nm gold core had the highest drug loading and release efficiency, the conjugate with a 10-nm gold core displayed the best antitumor efficacy toward the liver cancer models. This was because it showed the deepest tumor permeability and the highest tumor cell-killing ability of Dox transported by the relatively small GNPs. This study provides important evidence for better understanding the effect of size on in vitro and in vivo properties of potential therapeutic nanosystems and their structure design.

关键词： size effect doxorubicin-conjugated gold nanoparticles antitumor efficacy tumor penetration liver cancer

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Dynamic changes of the complex coupling relationships between ecosystem services and socio-ecological factors and the impact of human activities: Insights from network analysis

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Applied Geography 2025年 181卷

作者： Jie Zhang Chong Jiang Jianjun Qu Yixin Wang Jinxin Shi Ying Zhao College of Urban and Environmental Sciences Northwest University Xi'an 710127 China SouthernMarine Science and Engineering Guangdong Laboratory (Guangzhou) Guangzhou 511458 China State Key Laboratory of Urban and Regional Ecology Research Centre for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China State Key Laboratory of Geo-Information Engineering and Key Laboratory of Surveying and Mapping Science and Geospatial Information Technology of MNR CASM Beijing 100036 China Middle Yarlung Zangbo River Natural Resources Observation and Research Station of Tibet Autonomous Region Chengdu 610036 China Dongying Base of Integration Between Industry and Education for High-quality Development of Modern Agriculture Ludong University Dongying 257509 China Yellow River Engineering Consulting Co. Ltd. Zhengzhou 450003 China

Understanding the coupling relationships linking ecosystem services (ESs) and socio-ecological factors (SEF) is important to the sustainability of ecosystems. However, the majority of earlier research concentrated on the separate effects of SEF on ESs, without thoroughly investigating their coupling dynamics, trends, and the role of human activities. To address this gap, we analyzed the spatiotemporal variation of the ESs on Hainan Island from 2000 to 2020, including food production (FP), soil conservation (SC), water yield (WY), carbon sequestration (CS), water purification (WP), and habitat quality (HQ). Network analysis and the generalized additive model were used to investigate the coupling relationships and trends linking ESs and SEF. We also evaluated the variations of this coupling relationship under different human activity intensities. The results showed that HQ, WP, and CS exhibited relatively small changes during the study period, whereas SC, WY, and FP showed greater fluctuations. The coupling relationships linking ESs and SEF gradually weakened over time, with network complexity and connectivity declining. The positive contributions of HQ, CS, normalized difference vegetation index, and landscape pattern factors to network connectivity and complexity gradually diminished. In contrast, the negative contributions of SEF, including the percentage of construction land, gross domestic product, and percentage of cultivated land gradually increased. As human activity intensity increased, network connectivity and complexity showed a declining trend. This study not only offers new insights into comprehending the complex relationships linking ESs and SEF, but also provides theoretical support for future ecological protection policies on Hainan Island.

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Application of Deep Object Detection in Underwater Acoustic Pulse Interception

Application of Deep Object Detection in Underwater Acoustic ...

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OCEANS - Europe

作者： Yue Li Xiaochuan Ma Yu Liu Lei Wang Xuan Li Dongyu Yuan University of Chinese Academy of Sciences Beijing China Key Laboratory of Information Technology for AUV’s Chinese Academy of Science

Underwater acoustic pulse interception is an important task for underwater signal processing system, including the detection and identification of unknown acoustic pulses. An acoustic pulse interception method based on deep learning is proposed. The interception system consists of a pulse detection network and a DOA estimation network. The pulse detection neural network is used to achieve multi-pulse detection and bounding box inference on the spectrogram. The phase component of the short-time Fourier transform coefficients in the time-frequency bounding box is extracted. Then the DOA estimation network learns the phase feature to figure out the direction of arrival of each detected pulse by regression. Finally, the number of sources and their DOA estimates could be obtained through such operations as outlier removal and data fusion. Simulation results show that this method is able to achieve reliable pulse detection, source number estimation and high precision DOA estimation in underwater acoustic environment.

关键词： Direction-of-arrival estimation Estimation Feature extraction Object detection Deep learning Time-frequency analysis Signal detection

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Giant Chern number of a Weyl nodal surface without upper limit

arXiv

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arXiv 2022年

作者： Ma, Junzhang Zhang, S.-N. Song, J.P. Wu, Q.-S. Ekahana, S.A. Naamneh, M. Radovic, M. Strocov, V.N. Gao, S.-Y. Qian, T. Ding, H. He, K. Manna, K. Felser, C. Plumb, N.C. Yazyev, O.V. Xiong, Y.-M. Shi, M. Department of Physics City University of Hong Kong Kowloon Hong Kong Swiss Light Source Paul Scherrer Institute Villigen PSI CH-5232 Switzerland City University of Hong Kong Shenzhen Research Institute Shenzhen China Hong Kong Institute for Advanced Study City University of Hong Kong Kowloon Hong Kong Institute of Physics École Polytechnique Fédérale de Lausanne LausanneCH-10 15 Switzerland LausanneCH-1015 Switzerland Anhui Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field Laboratory HFIPS Anhui Chinese Academy of Sciences Hefei230031 China University of Science and Technology of China Anhui Hefei230026 China Department of Physics Ben-Gurion University of the Negev Beer-Sheva84105 Israel Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences Beijing100190 China Songshan Lake Materials Laboratory Guangdong Dongguan China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences Beijing100049 China Department of Physics Tsinghua University Beijing100084 China Max Planck Institute for Chemical Physics of Solids DresdenD-01187 Germany Department of Physics Indian Institute of Technology Delhi Hauz Khas New Delhi110016 India Department of Physics School of Physics and Optoelectronics Engineering Anhui University Hefei230601 China

Weyl nodes can be classified into zero-dimensional (0D) Weyl points (WPs), 1D Weyl nodal lines (WNL) and 2D Weyl nodal surfaces (WNS), which possess finite Chern numbers. Up to date, the largest Chern number of WPs identified in Weyl semimetals is 4, which is thought to be a maximal value for linearly crossing points in solids. On the other hand, whether the Chern numbers of nonzero-dimensional linear crossing Weyl nodal objects have one upper limit is still an open question. In this work, combining angle-resolved photoemission spectroscopy with density functional theory calculations, we show that the chiral crystal AlPt hosts a cubeshaped charged Weyl nodal surface which is formed by the linear crossings of two singly-degenerate bands. Different to conventional Weyl nodes, the cube-shaped nodal surface in AlPt is enforced by nonsymmorphic chiral symmetries and time reversal symmetry rather than accidental band crossings, and it possesses a giant Chern number |C| = 26. Moreover, our results and analysis prove that there is no upper limit for the Chern numbers of such kind 2D Weyl nodal object. © 2022, CC BY.

关键词： Density functional theory

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Total Factor Productivity analysis of Industrial Processes Based on Malmquist Model

Total Factor Productivity Analysis of Industrial Processes B...

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作者： Yongming Han Mingxing Zhang Zhiqiang Geng Kai Chen Yajie Wang Qin Wei Zhi Ouyang Guizhou Provincial Key Laboratory of Public Big Data College of Information Science& Technology Beijing University of Chemical Technology College of Information Science & Technology Beijing University of Chemical Technology Guizhou Academy of Science

The production of industrial process is the key factor of evaluating the national industry production ***,this paper proposes total factor productivity analysis method based on Malmquist model to analyze the production efficiency statically and *** on the input and output data of ethylene production plants in China,the total factor production index of ethylene production plants in industrial processes is decomposed into technical efficiency,technical progress,pure technical efficiency and scale efficiency through the Malmquist model based on the data envelopment analysis(DEA).Moreover,the energy efficiency of ethylene production plants can be improved.

关键词： DEA Malmquist index Ethylene production Total factor productivity Energy efficiency

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analysis of the effect of fretting wear on key structural components of TB6 titanium alloy with actual failure cases

Analysis of the effect of fretting wear on key structural co...

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2018 International Conference on Advanced Electronic Materials, Computers and Materials Engineering, AEMCME 2018

作者： Kong, Huanping Liu, Changkui AECC Beijing Institute of Aeronautical Materials Beijing China Beijing Key Laboratory of Aeronautical Materials Testing and Evaluation Beijing China Aviation Key Laboratory of Science and Technology on Aeronautical Materials Testing and Evaluation Beijing China

As the main metal structure materials, titanium alloys have been widely applied in aerospace and other military industries. Titanium alloy develops on the way of high performance and functionalization. Compared with other materials, titanium alloy has high surface integrity and high fretting damage sensitivity. In this paper, the failure case of TB6 high strength titanium alloy key structural parts is taken as the breakthrough point to analyze the effect of surface fretting wear damage on its performance. The appearance inspection, macro and micro morphology observation and energy spectrum analysis were carried out, and the microstructure examination and hardness test were also adopted. The results showed that the fracture property of lug of TB6 high strength titanium alloy was fatigue fracture, and the fretting wear damage of the inner surface of lug hole was the main reason for the fatigue crack initiation. This case is a typical example of titanium alloy structure failure due to fretting wear, which provides reference for the prevention of the recurrence of such faults. © Published under licence by IOP Publishing Ltd.

关键词： Titanium alloys

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The environmental dependence of Spitzer dusty Supernovae

arXiv

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arXiv 2023年

作者： Xiao, Lin Szalai, Tamás Galbany, Lluís Fox, Ori Hu, Lei Hu, Maokai Yang, Yi Moriya, Takashi J. Pessi, Thallis Han, Zhanwen Wang, Xiaofeng Yan, Shengyu Department of Physics Hebei University Baoding071002 China Hebei Key Laboratory of High-precision Computation and Application of Quantum Field Theory Baoding071002 China Hebei Research Center of the Basic Discipline for Computational Physics Baoding071002 China Department of Experimental Physics Institute of Physics University of Szeged Dóm tér 9 SzegedH-6720 Hungary HUN-REN–SZTE Stellar Astrophysics Research Group H-6500 BajaSzegedi út Kt. 766 Hungary Campus UAB Carrer de Can Magrans s/n BarcelonaE-08193 Spain BarcelonaE-08034 Spain Space Telescope Science Institute 3700 San Martin Drive BaltimoreMD21218 United States McWilliams Center for Cosmology Department of Physics Carnegie Mellon University 5000 Forbes Ave PittsburghPA15213 United States Purple Mountain Observatory Chinese Academy of Sciences Nanjing210023 China Tsinghua University Beijing100084 China Department of Astronomy University of California BerkeleyCA94720-3411 United States National Astronomical Observatory of Japan National Institutes of Natural Sciences 2-21-1 Osawa Mitaka Tokyo181-8588 Japan Graduate Institute for Advanced Studies SOKENDAI 2-21-1 Osawa Mitaka Tokyo181-8588 Japan School of Physics and Astronomy Monash University ClaytonVIC3800 Australia Instituto de Estudios Astrofísicos Facultad de Ingeniería y Ciencias Universidad Diego Portales Av. Ejército Libertador 441 Santiago Chile Yunnan Observatories Chinese Academy of Sciences Kunming650216 China Key Laboratory for the Structure and Evolution of Celestial Objects Yunnan Observatories CAS Kunming650216 China International Centre of Supernovae Yunnan Key Laboratory Kunming650216 China Beijing Planetarium Beijing Academy of Science and Technology Beijing100044 China

Thanks to the mid-infrared capability offered by Spitzer, systematic searches of dust in SNe have been carried out over the past decade. Studies have revealed the presence of a substantial amount of dust over a broad range of SN subtypes. How normal SNe present mid-IR excess at later time and turn out to be dusty SNe can be affected by several factors, such as mass-loss history and envelope structure of progenitors and their explosion environment. All these can be combined and related to their environmental properties. A systematic analysis of SNe that exploded under a dusty environment could be of critical importance to measure the properties of the dust-veiled exploding stars, and whether such an intense dust production process is associated with the local environment. In this work, we firstly use the IFS data to study the environmental properties of dusty SNe compared to those of normal ones, and analyze correlations between the environmental properties and their dust parameters. We find that dusty SNe have a larger proportion located at higher SFR regions compared to the normal types. The occurrence of dusty SNe is less dependent on metallicity, with the oxygen abundance spanning from subsolar to oversolar metallicity. We also find the host extinction of dusty SNe scatters a lot, with about 40% of dusty SN located at extremely low extinction environments, and another 30% of them with considerably high host extinction of E(B-V)>0.6 mag. Copyright © 2023, The Authors. All rights reserved.

关键词： Supernovae

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Dynamic fusion based federated learning for COVID-19 detection

arXiv

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arXiv 2020年

作者： Zhang, Weishan Zhou, Tao Lu, Qinghua Wang, Xiao Zhu, Chunsheng Sun, Haoyun Wang, Zhipeng Lo, Sin Kit Wang, Fei-Yue China Data61 CSIRO Australia State Key Laboratory of Management and Control for Complex Systems Institute of Automation Chinese Academy of Sciences Beijing China SUSTech Institute of Future Networks Southern University of Science and Technology China

Medical diagnostic image analysis (e.g., CT scan or X-Ray) using machine learning is an efficient and accurate way to detect COVID-19 infections. However, sharing diagnostic images across medical institutions is usually not allowed due to the concern of patients’ privacy. This causes the issue of insufficient datasets for training the image classification model. Federated learning is an emerging privacy-preserving machine learning paradigm that produces an unbiased global model based on the received updates of local models trained by clients without exchanging clients’ local data. Nevertheless, the default setting of federated learning introduces huge communication cost of transferring model updates and can hardly ensure model performance when data heterogeneity of clients heavily exists. To improve communication efficiency and model performance, in this paper, we propose a novel dynamic fusion-based federated learning approach for medical diagnostic image analysis to detect COVID-19 infections. First, we design an architecture for dynamic fusion-based federated learning systems to analyse medical diagnostic images. Further, we present a dynamic fusion method to dynamically decide the participating clients according to their local model performance and schedule the model fusion-based on participating clients’ training time. In addition, we summarise a category of medical diagnostic image datasets for COVID-19 detection, which can be used by the machine learning community for image analysis. The evaluation results show that the proposed approach is feasible and performs better than the default setting of federated learning in terms of model performance, communication efficiency and fault tolerance. Copyright © 2020, The Authors. All rights reserved.

关键词： Image analysis

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