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2019 IEEE International Conference on Signal, Information and Data Processing, ICSIDP 2019

作者： Zhang, Ying Xiong, Wei Dong, Xichao Hu, Cheng Liu, Chengxiang Sun, Yang Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China School of Information and Electronics Beijing Institute of Technology Beijing China Key Laboratory of Electronic and Information Technology in Satellite Navigation Ministry of Education Beijing China

ISBN: (纸本)9781728123455

Geosynchronous Spaceborne-Airborne Bistatic multichannel SAR (GEO-SABM SAR) maintains the fine temporal sampling and wide coverage characteristics of monostatic GEO SAR. But due to the PRF of GEO platform is very low, azimuth spectrum aliasing (ASA) will occur in GEO-SABM SAR which will make a moving target divided into several sub-targets. In this paper, a location method for ground moving target with ASA has given. From the simulation results, the moving target can be discriminated and located. © 2019 IEEE.

关键词： Synthetic aperture radar

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Modified robust optimal adaptive control for flight environment simulation system with heat transfer uncertainty

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Chinese Journal of Aeronautics 2021年第2期34卷 420-431页

作者： Meiyin ZHU Xi WANG Xitong PEI Song ZHANG Zhihong DAN Nannan GU Shubo YANG Keqiang MIAO Huairong CHEN Jiashuai LIU School of Energy and Power Engineering Beihang UniversityBeijing 100083China Collaborative Innovation Center for Advanced Aero Engine Bejing 100083China Science and Technology on Altitude Simulation Laboratory AECC(Aero Engine Corporation of China)Sichuan Gas Turbine EstablishmentMianyang 621000China

To solve the rapid transient control problem of Flight Environment simulation system(FESS) of Altitude Ground Test Facilities(AGTF) with large heat transfer uncertainty and disturbance, a new adaptive control structure of modified robust optimal adaptive control is *** mathematic modeling of FESS is given and the influence of heat transfer is analyzed through energy view. To consider the influence of heat transfer in controller design, we introduce a matched uncertainty that represents heat transfer influence in the linearized system of FESS. Based on this linear system, we deduce the design of modified robust optimal adaptive control law in a general way. Meanwhile, the robust stability of the modified robust optimal adaptive control law is proved through using Lyapunov stability theory. Then, a typical aero-engine test condition with Mach Dash and Zoom-Climb is used to verify the effectiveness of the devised adaptive controller. The simulation results show that the designed controller has servo tracking and disturbance rejection performance under heat transfer uncertainty and disturbance;the relative steady-state and dynamic errors of pressure and temperature are both smaller than 1% and 0.2% respectively. Furthermore,the influence of the modification parameter c is analyzed through simulation. Finally, comparing with the standard ideal model reference adaptive controller, the modified robust optimal adaptive controller obviously provides better control performance than the ideal model reference adaptive controller does.

关键词： Altitude ground test facilities Flight environment simulation system Heat transfer Model reference adaptive control Optimal control modification Uncertainty

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Enhanced null message algorithm for hybrid parallel simulation systems with large disparity in time step

Enhanced null message algorithm for hybrid parallel simulati...

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International Workshop/Symposium on Distributed simulation and Real-Time Applications (DS-RT)

作者： Bin Wang Yanlong Zhai Zishuo Wang Han Zhang Duzheng Qing Beijing Engineering Research Center of Massive Language Information Processing and Cloud Computing Applications Bijing Institute of Technology Beijing China Science and Technology on Special System Simulation Laboratory Beijing Simulation Center China

ISBN: (纸本)9781509035069

Modeling and simulation has received significant attention over the years for its ability to understand and transform real world systems. With the increasing of complexity and scale of the simulated systems, more computational power is required. Parallel discrete event simulation(PDES) is an important technology to integrate parallel computing into modeling and simulation. Time synchronization algorithm is the core of PDES, which determines the correctness and efficiency of the simulation. Traditional conservative synchronization algorithms, such as Chandy-Misra-Bryant(CMB) null message algorithm, use null message to synchronize the state and avoid deadlock among logical processes(LPs). But hybrid simulation systems contains both continuous models and discrete models, continuously changing states is typically modeled using time steps in hybrid simulation system. Therefore, hybrid systems with large disparity in time step are very common in real simulation systems. However, current conservative synchronization algorithm has not been fully investigated for this type of simulation systems and will generate massive synchronization messages. This paper proposed an enhanced null message algorithm for hybrid simulation systems with large disparity in time step. It extended the CMB algorithm by adding simulation time in null message request messages. This could significantly reduce the number of synchronization messages. Experimental results showed that our synchronization algorithm outperforms the CMB algorithm by reducing a great number of synchronization messages.

关键词： Synchronization Computational modeling Atmospheric modeling Adaptation models system recovery Ports (Computers) Complex systems

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CeO_(2)-supported Fe,Co and Ni toward CO_(2) hydrogenation:Tuning catalytic performance via metal-support interaction

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Journal of Rare Earths 2023年第6期41卷 926-932,I0005页

作者： Bolang Li Fei Wang Kai Li Ping Ning Min Chen Changbin Zhang Faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming 650500China National-Regional Engineering Center for Recovery of Waste Gases from Metallurgical and Chemical Industries Kunming University of Science and TechnologyKunming 650500China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environment SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The chemical transformation of CO_(2) produces carbon compounds that can be used as precursors for the production of chemicals and ***,we investigated the activity and selectivity of the transition metals(Fe,Co,and Ni)supported on CeO_(2) catalyst for CO_(2) hydrogenation at atmospheric *** found that Ni/CeO_(2) shows the highest CO_(2)conversion compared with Fe/CeO_(2) and Co/CeO_(2).Besides,Co/CeO_(2)and Ni/CeO_(2) exhibit nearly 100%CH_(4)selectivity while Fe/CeO_(2) inclines to produce *** characterization results show that the metal-support interaction order is Fe/CeO_(2)>Co/CeO_(2)>Ni/CeO_(2),the weak metal-support inte raction over Ni/CeO_(2)benefits the activation of H_(2) and then promotes the activity of CO_(2) ***,in situ DRIFTS results demonstrate that monodentate formate species rather than bidentate formate are the active *** main route of CO_(2) hydrogenation to CH_(4) is that CO_(2) is firstly transformed to m-HCOO*and then direct hydrogenation of the m-HCOO*to CH_(4).This study provides insights into the understanding of the mechanisms of CO_(2) hydrogenation on CeO_(2)based catalysts.

关键词： Ni CeO_(2) Metal-support interaction CO_(2)hydrogenation Rare earths

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Research on behavioral decision method of simulation entity based on cognitive model

Research on behavioral decision method of simulation entity ...

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2013 International Conference on Applied Mechanics, Mechatronics and Intelligent system, AMMIS 2013

作者： Yang, Haitao Li, Peng Wei Zhao, Hong Li Science and Technology on Complex Electronic System Simulation Laboratory Academy of Equipment Beijing 101416 China Company of Postgraduate Management Academy of Equipment Beijing 101416 China Academy of Equipment Beijing 101416 China

ISBN: (纸本)9783037857625

This paper studies how to use the cognitive model to model the behavioral decision-making for the tactical level simulation. The decision making process includes initial behavior planning and behavior modification. This method has the advantages of accuracy and real-time, this makes the behaviors of the simulation entity more realistic and improves the credibility of simulation. © (2013) Trans Tech Publications, Switzerland.

关键词： Decision making

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Surface-enhanced Raman scattering for mixing state characterization of individual fine particles during a haze episode in beijing,China

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Journal of Environmental sciences 2021年第6期33卷 216-224页

作者： Hui Chen Fengkui Duan Jingjing Du Ranhao Yin Lidan Zhu Jinlu Dong Kebin He Zhenli Sun Suhua Wang MOE Key Laboratory of Resources and Environmental System Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Guangdong Provincial Key Laboratory of Petrochemcial Pollution Processes and Control School of Environmental Science and EngineeringGuangdong University of Petrochemical TechnologyMaoming 525000China

The nondestructive characterization of the mixing state of individual fine particles using the traditional single particle analysis technique remains a *** this study,fine particles were collected during haze events under different pollution levels from September 5 to 112017 in beijing,China.A nondestructive surface-enhanced Raman scattering(SERS)technique was employed to investigate the morphology,chemical composition,and mixing state of the multiple components in the individual fine *** image and SERS spectral analysis results show that soot existing in the form of opaque material was predominant during clear periods(PM_(2.5)≤75μg/m^(3)).During polluted periods(PM_(2.5)>75μg/m^(3)),opaque particles mixed with transparent particles(nitrates and sulfates)were generally *** classical least squares analysis further identified the relative abundances of the three major components of the single particles:soot(69.18%),nitrates(28.71%),and sulfates(2.11%).A negative correlation was observed between the abundance of soot and the mass concentration of PM_(2.5).Furthermore,mapping analysis revealed that on hazy days,PM_(2.5)existed as a core-shell structure with soot surrounded by nitrates and *** mixing state analysis method for individual PM_(2.5)particles provides information regarding chemical composition and haze formation mechanisms,and has the potential to facilitate the formulation of haze prevention and control policies.

关键词： PM_(2.5) Surface-enhanced Raman scattering Individual fine particle Nitrate Sulfate Soot

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Constructing a Raman and surface-enhanced Raman scattering spectral reference library for fine-particle analysis

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Journal of Environmental sciences 2022年第8期34卷 1-13页

作者： Hui Chen Fengkui Duan Kebin He Jingjing Du Zhenli Sun Suhua Wang Key Laboratory of Resources and Environmental System Optimization of Ministry of Education College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Guangdong Provincial Key Laboratory of Petrochemcial Pollution Processes and Control School of Environmental Science and EngineeringGuangdong University of Petrochemical TechnologyMaoming 525000 China

Fine particles associated with haze pollution threaten the health of over 400 million people in China. Owing to excellent non-destructive fingerprint recognition characteristics, Raman and surface-enhanced Raman scattering(SERS) are often used to analyze the composition of fine particles to determine their physical and chemical properties as well as reaction mechanisms. However, there is no comprehensive Raman spectral library of fine particles. Furthermore, various studies that used SERS for fine-particle composition analysis showed that the uniqueness of the SERS substrates and different excitation wavelengths can produce a different spectrum for the same fine-particle component. To overcome this limitation, we conducted SERS experiments with a portable Raman spectrometer using two common SERS substrates(silver(Ag) foil and gold nanoparticles(Au NPs)) and a 785 nm laser. Herein, we introduced three main particle component types(sulfate-nitrate-ammonium(SNA), organic material, and soot) with a total of 39 chemical substances. We scanned the solid Raman, liquid Raman, and SERS spectra of these substances and constructed a fine-particle reference library containing 105 spectra. Spectral results indicated that for soot and SNA, the differences in characteristic peaks mainly originated from the solid-liquid phase transition;Ag foil had little effect on this difference, while the Au NPs caused a significant red shift in the peak positions of polycyclic aromatic hydrocarbons. Moreover, with various characteristic peak positions in the three types of spectra, we could quickly and correctly distinguish substances. We hope that this spectral library will aid in the future identification of fine particles.

关键词： Raman Surface-enhanced Raman scattering(SERS) Spectral library Fine-particle

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New WHO global air quality guidelines help prevent premature deaths in China

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National science Review 2022年第4期9卷 10-12页

作者： Tao Xue Guannan Geng Xia Meng Qingyang Xiao Yixuan Zheng Jicheng Gong Jun Liu Wei Wan Qiang Zhang Haidong Kan Shiqiu Zhang Tong Zhu Institute of Reproductive and Child Health/National Health Commission Key Laboratory of Reproductive Health and Department of Epidemiology and Biostatistics School of Public HealthPeking University State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua University School of Public Health Key Laboratory of Public Health Safety of the Ministry of Educationand Key Laboratory of Health Technology Assessment of the Ministry of HealthFudan University Center of Air Quality Simulation and System Analysis Chinese Academy of Environmental Planning College of Environmental Sciences and Engineering Peking University School of Energy and Environmental Engineering University of Science and Technology Beijing Clean Air Asia Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua University

The air quality guidelines （AQGs） issued by the World Health Organization （WHO） in 2005 are key references for the National Ambient Air Quality Standards （NAAQSs） in *** 22September 2021,the WHO issued new AQGs （NAQGs）[1],which propose more stringent targets to control exposure to multiple air pollutants,including fine particulate matter (PM2.5) and ozone （O3）,to which,in 2019,451 million premature deaths,globally,were attributable [2].

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Impacts of synoptic circulation on surface ozone pollution in a coastal eco-city in Southeastern China during 2014-2019

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Journal of Environmental sciences 2023年第5期127卷 143-157页

作者： Yu Yan Xuesong Wang Zhengchao Huang Kun Qu Wenbin Shi Zimu Peng Limin Zeng Shaodong Xie Yuanhang Zhang State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China International Joint Laboratory for Regional Pollution Control Ministry of EducationBeijing 100816China Center for Environmental Education and Communications of Ministry of Ecology and Environment Beijing 100020China Beijing Innovation Center for Engineering Science and Advanced Technology Peking UniversityBeijing 100871China CAS Center for Excellence in Regional Atmospheric Environment Chinese Academy of SciencesXiamen 361021China

The coastal eco-city of Fuzhou in Southeastern China has experienced severe ozone(O_(3))episodes at times in recent *** this study,three typical synoptic circulations types(CTs)that influenced more than 80%of O_(3) polluted days in Fuzhou during 2014-2019 were identified using a subjective *** characteristics of meteorological conditions linked to photochemical formation and transport of O_(3) under the three CTs were *** Air Quality Model with extensions was applied to simulate O_(3) episodes and to quantify O_(3) sources from different regions in *** Fuzhou was located to the west of a high-pressure system(classified as“East-ridge”),more warm southwesterly currents flowed to Fuzhou,and the effects of cross-regional transport from Guangdong province and high local production promoted the occurrence of O_(3) *** a uniform pressure field with a low-pressure system occurring to the east of Fuzhou(defined as“East-low”),stagnant weather conditions caused the strongest local production of O_(3) in the atmospheric boundary *** by high-pressure systems over the mainland(categorized as“Inland-high”),northerly airflows enhanced the contribution of cross-regional transport to O_(3) in *** abnormal increases of the“East-ridge”and“Inland-high”were closely related to O_(3) pollution in Fuzhou in April and May 2018,resulting in the annual maximum number of O_(3) polluted days during recent ***,the rising number of autumn O_(3) episodes in 2017-2019 was mainly related to the“Inland-high”,indicating the aggravation of cross-regional transport and highlighting the necessity of enhanced regional collaboration and efforts in combating O_(3) pollution.

关键词： Ozone pollution Synoptic circulation Regional transport Chemical production

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Controlling outsourced emissions matters for decarbonizing China's urban wastewater sector at all life-cycle stages

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Cell Reports Sustainability 2025年第4期2卷

作者： Zhang, Linmei Liu, Beibei Chen, Bin Chen, Shaoqing School of Economics and Management Zhejiang Sci-Tech University Hangzhou 310018 China Zhejiang Academy of Eco-Civilization Zhejiang Sci-Tech University Hangzhou 310018 China School of Environmental Science and Engineering Sun Yat-sen University Guangzhou 510275 China State Key Laboratory of Pollution Control & Resource Reuse School of Environment Nanjing University Nanjing 210023 China The Johns Hopkins University-Nanjing University Center for Chinese and American Studies Nanjing 210093 China State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology (Sun Yat-sen University) Guangzhou 510275 China Institute of Carbon Neutrality and Green Development (Sun Yat-sen University) Guangzhou 510275 China

The climatic impact of the wastewater sector is significant given greenhouse gas (GHG) emissions through the whole supply chain. However, there has been a lack of investigation into trade-related leakage and the drivers of GHG emissions associated with wastewater treatment. Here, we develop a system-based modeling framework to track the outsourcing of emissions across regions, quantifying key socioeconomic drivers across the life-cycle stages of wastewater treatment in China, covering over 6,000 treatment plants nationwide. We find that outsourced emissions constitute over 41% of the total carbon footprint of China's wastewater sector. Over 90% of wastewater-related embodied GHG emissions traced back to production in northern, northwestern, and northeastern China. Variations in carbon intensity, production structure, and final demand structure can play an important role in emission reduction amid construction, treatment, and reuse stages. Our findings highlight the importance of coordinating supply-chain emission mitigation among regions for a deep decarbonization of the wastewater sector. © 2025 The Author(s)

关键词： carbon footprint Chinese regions outsourcing of emissions socioeconomic drivers urban wastewater sector

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