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35th European Modeling and simulation Symposium, EMSS 2023

作者： Zhang, Huan Li, Wei Geng, HuaPin Ma, Ping Yang, Ming Control and Simulation Center Harbin Institute of Technology Harbin150080 China National Key Laboratory of Modeling and Simulation for Complex Systems Harbin150080 China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing100074 China

ISBN: (纸本)9788885741881

Complex simulation systems usually need to satisfy the credibility requirements and the credibility of complex simulation systems is inextricably linked to the credibility of simulation sub-systems. Hence, in order to guarantee the credibility of complex simulation systems meets requirements, it is necessary to allocate the credibility of simulation sub-systems. Complex simulation systems are composed of several correlative simulation sub-systems and their credibility has correlation relationships, which makes it difficult to obtain the credibility of simulation sub-systems quickly. The existing works mostly ignore the relationships between the sub-systems and are difficult to generate the credibility allocation results of simulation sub-systems. In this paper, we model the credibility allocation problem as a probabilistic inference problem based on the pairwise Markov random field (PMRF). In addition, we apply several inference algorithms to perform the inference exactly and approximately in the credibility PMRF. Finally, experiments are conduted on the air defense combat complex simulation system, and the experiment results demonstrate that the proposed method can obtain the credibility allocation results quickly and accurately. © 2023 The Authors.

关键词： Inference engines

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Climatic and Biotic Controls of Evapotranspiration Across Grassland Ecosystems on the Tibetan Plateau

SSRN

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SSRN 2025年

作者： Peng, Siyuan Yang, Yue Luo, Dengnan Zeng, Xiang Liang, Minqi Tao, Long Zhang, Guangru Li, Pan Liao, Weijie Guo, Qun Cao, Ruochen Li, Yuzhe Zhang, Weirong Hu, Zhongmin Hainan Baoting Tropical Rainforest Ecosystem Observation and Research Station School of Ecology Hainan University Haikou570228 China Department of Geography Faculty of Arts and Sciences Beijing Normal University Zhuhai519087 China Facility of Geographical Science Beijing Normal University Beijing100875 China Zhuhai Branch of State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Zhuhai519087 China School of Geography South China Normal University Shipai Campus Guangzhou510631 China School of Atmospheric Sciences Guangdong Province Data Center of Terrestrial and Marine Ecosystems Carbon Cycle Sun Yat-sen University Guangdong Zhuhai510245 China Key Lab of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing100101 China College of Resources and Environment University of Chinese Academy of Sciences Beijing101408 China International Institute for Earth System Sciences Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing University Jiangsu210023 China Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology Key Laboratory for Land Satellite Remote Sensing Applications of Ministry of Natural Resources School of Geography and Ocean Science Nanjing University Jiangsu210023 China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China

Study region: The Tibetan Plateau in China, the Third Pole of the *** focus: Accurate descriptions of spatial variation in evapotranspiration (ET) and its components on the Tibetan Plateau (TP) are crucial for understanding the dynamics of the regional water cycle and energy balance. However, how various environmental factors affect ET and its components remains unclear. This study addresses this gap using observational data from 14 sites and employing the Shuttleworth-Wallace-Hu (SWH) model to examine the spatial relationships between ET, its components, and underlying *** hydrological insights for the region: The SWH model parameters were optimized using the Monte Carlo method, achieving a satisfactory model performance with an average R² of 0.75. The ratio of transpiration to ET was generally higher in alpine meadows (0.55) than alpine steppes (0.39). Across the TP, precipitation and the leaf area index together shaped spatial variation in ET and transpiration. Precipitation emerged as the primary driver of interannual variation in ET, while the leaf area index strongly regulated the proportion of ET accounted for by transpiration. Furthermore, above aridity index values of 0.73, grassland ecosystems transitioned from water to energy. This finding is significant as it challenges the common application of an aridity index value of 0.65 to distinguish arid from humid regions. It suggests that TP grasslands, with an AI of 0.65-0.73, remain primarily water-limited. © 2025, The Authors. All rights reserved.

关键词： Monte Carlo methods

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Vertical distribution of aerosol optical properties based on aircraft measurements over the Loess Plateau in China

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Journal of Environmental sciences 2015年第8期27卷 44-56页

作者： Junxia Li Xingang Liu Liang Yuan Yan Yin Zhanqing Li Peiren Li Gang Ren Lijun Jin Runjun Li Zipeng Dong Yiyu Li Junmei Yang Weather Modification Office of Shanxi Province Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science and Technology State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University College of Global Change and Earth System Science Beijing Normal University Meteorological Institute of Shaanxi Province

Vertical distributions of aerosol optical properties based on aircraft measurements over the Loess Plateau were measured for the first time during a summertime aircraft campaign, 2013 in Shanxi, China. Data from four flights were analyzed. The vertical distributions of aerosol optical properties including aerosol scattering coefficients（σsc）, absorption coefficients（σab）,Angstr？m exponent（α）, single scattering albedo（ω）, backscattering ratio（βsc）, aerosol mass scattering proficiency（Q sc） and aerosol surface scattering proficiency（Q sc′） were obtained. The mean statistical values of σsc were 77.45 Mm-1（at 450 nm）, 50.72 Mm-1（at 550 nm）, and32.02 Mm-1（at 700 nm）. The mean value of σab was 7.62 Mm-1（at 550 nm）. The mean values ofα, βsc and ω were 1.93, 0.15, and 0.91, respectively. Aerosol concentration decreased with altitude. Most effective diameters（ED） of aerosols were less than 0.8 μm. The vertical profiles of σsc,, α, βsc, Q sc and Q sc′ showed that the aerosol scattering properties at lower levels contributed the most to the total aerosol radiative forcing. Both α and βsc had relatively large values, suggesting that most aerosols in the observational region were small particles. The mean values of σsc, α, βsc, Q sc, Q sc′, σab and ω at different height ranges showed that most of the parameters decreased with altitude. The forty-eight hour backward trajectories of air masses during the observation days indicated that the majority of aerosols in the lower level contributed the most to the total aerosol loading, and most of these particles originated from local or regional pollution emissions.

关键词： Vertical distribution Optical properties Aircraft measurements The Loess Plateau

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A LSTM-based method for simulation execution validity evaluation 33

A LSTM-based method for simulation execution validity evalua...

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33rd European Modeling and simulation Symposium, EMSS 2021

作者： Wang, YuLun Li, Wei Li, Jing Control and Simulation Center Harbin Institute of Technology Harbin150080 China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing100074 China

This paper improves the concept of simulation execution validity and a methodology to assess the complex simulation system. As the complexity of the simulation system gradually rises, the magnitude of the simulation data obtained continues to increase, which makes it extremely difficult for experts to provide expert knowledge to evaluate the execution validity of the simulation system. More precisely, the essence of execution validity is to dig out the hidden relationships in the simulation time series data and complete the classification task whether it is valid. Considering that machine learning can better complete the two tasks of mining data features and classification, this paper adopts long short-term memory, a neural network used to process time series data, to evaluate the execution validity. Finally, an experiment is conducted on a simulation system, and the results show that the evaluation method based on LSTM can accurately evaluate the validity of the simulation system, and can greatly improve the efficiency of evaluation. © 2021 The Authors.

关键词： Long short-term memory

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Twin Delayed Multi-Agent Deep Deterministic Policy Gradient

Twin Delayed Multi-Agent Deep Deterministic Policy Gradient

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Symposium of Image, Signal Processing, and Artificial Vision (STSIVA)

作者： Mengying Zhan Jinchao Chen Chenglie Du Yuxin Duan Northwestern Polytechnical University Xi’an China Beijing Simulation Center Science and Technology on Special System Simulation Laboratory Beijing China

ISBN: (纸本)9781665426565

Recently, reinforcement learning has made remarkable achievements in the fields of natural science, engineering, medicine and operational research. Reinforcement learning addresses sequence problems and considers long-term returns. This long-term view of reinforcement learning is critical to find the optimal solution of many problems. The existing multi- agent reinforcement learning algorithms have the problem of overestimation in estimating the Q value. Unfortunately, there have not been many studies on overestimation of agent reinforcement learning, which will affect the learning efficiency of reinforcement learning. Based on the traditional multi-agent reinforcement learning algorithm, this paper improves the actor network and critic network, optimizes the overestimation of Q value and adopts the update delayed method to make the actor training more stable. In order to test the effectiveness of the algorithm structure, the modified method is compared with the traditional MADDPG, DDPG and DQN methods in the simulation environment.

关键词： Training Conferences Reinforcement learning Delays Informatics Convergence

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Pattern Analysis and Placement Optimization of the Four-horn Monopulse for Terahertz Communication

Pattern Analysis and Placement Optimization of the Four-horn...

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2023 Cross Strait Radio science and Wireless technology Conference, CSRSWTC 2023

作者： Lu, Yong-Han Zhu, Zhong-Bo Ma, Jing Shi, Bin Zhang, Yu-Ting Peng, Lin Guilin University of Electronic Technology Key Laboratory of Microwave and Optical Wave Application Technology Guangxi Guilin541004 China National Key Laboratory of Science and Technology on Space Microwave Xi'an710100 China Beijing Simulation Center Science and Technology on Special System Simulation Laboratory Beijing100854 China School of Optoelectronic Engineering Guangxi Key Laboratory of Optoelectronic Information Processing Guilin University of Electronic Technology Guilin541004 China

ISBN: (纸本)9798350358971

The mobile node communication in terahertz monopulse system requires narrow beam to align with the mobile target precisely. In this paper, the radiation pattern of four-horn monopulse antenna is analyzed by use of the geometric optics (GO) and aperture field integration method (AFIM), and an efficient placement optimization to reduce the beamwidth of four-horn monopulse is presented. The optimization combines the genetic algorithm (GA) with GO-AFIM. The GA is employed to seek the optimal positions of the four horns, and the GO and AFIM are introduced into the fitness function of GA to evaluate the individual fitness. The optimization result has narrowed the beamwidth and enhanced gain of radiation pattern. Compared with the simulation in full wave software, the proposed method costs less time in pattern analysis and performs more efficiently in placement optimization. © 2023 IEEE.

关键词： aperture field integration method (AFIM) geometric optics (GO) placement optimization terahertz monopulse

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Removal of pharmaceutical in a biogenic/chemical manganese oxide system driven by manganese-oxidizing bacteria with humic acids as sole carbon source

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Journal of Environmental sciences 2023年第4期126卷 734-741页

作者： Tingming Ye Huijuan Liu Weixiao Qi Jiuhui Qu Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Center for Water and Ecology State Key Joint Laboratory of Environment Simulation and Pollution ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China University of Chinese Academy of Sciences Beijing 100049China

Bioaugmented sand filtration has attracted considerable attention because it can effectively remove contaminants in drinking water without additional chemical reagent *** this study,a synthesized chemical manganese dioxide (MnO_(2)) -coated quartz sand(MnQS) and biogenic manganese oxide (BioMnOx) composite system was proposed to simultaneously remove typical pharmaceutical contaminants and Mn_(2)+.We demonstrated a manganese-oxidizing bacterium,Pseudomonas ***-1,could oxidize Mn_(2)+to generate BioMnOxusing humic acids (HA) as sole carbon *** coaction of MnQS,QJX-1,and the generated BioMnOxin simultaneously removing caffeine and Mn_(2)+in the presence of HA was *** found a synergistic effect between *** and BioMnOxtogether significantly increased the caffeine removal efficiency from 32.8%(MnQS alone) and 21.5%(BioMnOxalone) to 61.2%.Meanwhile,Mn_(2)+leaked from MnQS was rapidly oxidized by QJX-1 to regenerate reactive BioMnOx,which was beneficial for continuous contaminant removal and system *** degradation intermediates of caffeine oxidized by MnQS and BioMnOxwere detected by LC-QTOF-MS analysis,which implied that caffeine was oxidized by a different ***,this work promotes the potential application of bioaugmented sand filtration in pharmaceutical removal in the presence of natural organic matter in drinking water.

关键词： Bioaugmentation MnO_(2)-coated quartz sand Manganese-oxidizing bacteria Humic acid Caffeine

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Shock Response in Cage-like Polynitrocubane High-Energy-Density Materials: Competition between Strain Energy and Structural Symmetry

Energetic Materials Frontiers

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Energetic Materials Frontiers 2025年

作者： Qing-guan Song Li Meng Sheng-li Jiang Lei Zhang Ze-yao Mo Institute of Applied Physics and Computational Mathematics Beijing 100088 China CAEP Software Center for High Performance Numerical Simulation Beijing 100088 China Institute of Chemical Materials China Academy of Engineering Physics Mianyang 621999 China School of Materials Science & Engineering Beijing Institute of Technology Beijing 100081 China State Key Laboratory of Explosion Science and Safety Protection Beijing Institute of Technology Beijing 100081 China

The cage-like structures provide a unique combination of strain energy for enhanced energy storage and hyperstatic constraints to stabilize the system, positioning them as promising pioneers in advancing high-energy-density materials (HEDMs). However, the shock response of cage-like HEDMs is highly complex and exhibits significant variability, posing a grand challenge in the underlying mechanisms. This study reveals that the shock response of cage-like HEDMs is regulated by the interplay between strain energy and structural symmetry, and introduces a physical model to quantitatively describe how they determine shock stability. The investigated systems include a comprehensive series of cage-like polynitrocubane HEDMs, with each carbon atom in the backbone progressively functionalized with nitro groups. Ab initio molecular dynamics (AIMD) simulations were employed to simulate dynamic and kinetic responses at shock velocities ranging from 8 km·s -1 to 11 km·s -1 , with validation provided by consistent Hugoniot curves that align with reported experimental data. Nitro groups at the carbon-based cage structure, recognized as explosion functional groups, were found to substantially increase the system's strain energy. However, an increasing number of nitro groups also intensified electrostatic repulsion among oxygen lone pairs, which weakens structural integrity and renders the material more susceptible to disassembly under shock conditions. Conversely, structural symmetry—including both the cage-like molecular conformation and spatial packing within the crystal lattice—was found to mitigate these destabilizing effects, effectively balancing the trade-off between energy storage and structural stability. Based on these findings, we propose a physical model that captures the essential factors driving shock initiation in cage-like polynitrocubane HEDMs, offering new insights to inform the design and application of novel advanced HEDMs.

关键词： shock stability cage-like high-energy-density materials strain energy structural symmetry strain tensor

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A Position Probability Prediction Method of Marine Moving Targets for Optimization Search by Satellite

A Position Probability Prediction Method of Marine Moving Ta...

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2024 IEEE International Conference on Control science and systems Engineering, ICCSSE 2024

作者： Zheng, Xiao Peng, Xiaodong Guo, Zhiyuan Qiang, Huimin Zhao, Junbao University of Chinese Academy of Science Laboratory of System Simulation and Concurrent Design Technology National Space Science Center Chinese Academy of Sciences Beijing China Beijing Remote Sensing Information Institute Beijing China

ISBN: (纸本)9798331517199

Marine moving ship target search has great application demand and development prospects in marine surveillance, marine search and rescue, customs anti-smuggling, and other aspects. Satellites are a vital means of searching for marine moving targets. Ground coverage for imaging satellites is relatively limited;the vast marine area makes searching for marine moving ships challenging. Target position prediction, used as the guidance information for satellite detection to reduce the uncertainty of the target position and improve search efficiency, is an essential approach to achieving target optimization search. This paper proposes a target position prediction method based on joint learning of multi-source factors for optimal satellite search of marine moving targets. Firstly, it analyzes the characteristics of marine moving targets and the factors affecting motion. Then, it puts forward the motion prediction model based on a deep neural network, integrating multifactor, like the state of the moving target, environmental attributes such as nautical charts, meteorology and hydrology, and kinematic constraints, to predict the target positional distribution probability. Finally, the target search strategy based on the maximum sum of the distribution probabilities of the satellite coverage area is adopted to improve target detection probability. The experiment results show that the prediction method can realize the target positional distribution probability prediction, reduce the uncertainty search when making the satellite search plan, and improve efficiency. © 2024 IEEE.

关键词： Deep neural networks

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Indoor visual navigation system based on paired-landmark for small UAVs

Indoor visual navigation system based on paired-landmark for...

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IEEE International Conference on Robotics and Biomimetics

作者： Tianmiao Wang Yicheng Zhang Chaolei Wang Jianhong Liang Han Gao Miao Liu Qinpu Guan Anqi Sun BeiHang University Beijing China Science and Technology on Special System Simulation Laboratory Beijing Simulation Center Beijing China Beihang University Beijing CN

ISBN: (纸本)9781479973989

This paper has presented an implementation of visual based non-GNSS navigation method for small VTOL (Vertically Taking-off and Landing) UAV (Unmanned Aerial Vehicle). A novel method of constructing landmarks is described in detail. It uses a pair of landmarks instead of the general landmark which usually is a single geometry or coding image. The paired-landmark method inherits general landmark methods' advantages of low-cost, high-efficiency and the ability of absolute positioning. And it also solves the problem of requiring too much different characteristic landmarks when handling large area navigation. The paired-landmark method has been verified by a real parameter simulation environment. Real flight experiment is also carried out to test the effectiveness and performance of the paired-landmark navigation method. It can be concluded that, besides achieved the expected positioning precision, the proposed system also reduced the consumption of calculation and memory space.

关键词： Cameras Aircraft Aircraft navigation Visualization Atmospheric modeling Estimation

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