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15th International Conference on Microwave and Millimeter Wave technology, ICMMT 2023

作者： Li, Zhi-Hao Ma, Jing Wu, Jin Huang, Jia-Jia Lu, Yong-Han Peng, Lin Guangxi Guilin541004 China Education Department of Guangxi Zhuang Autonomous Region Guangxi Guilin541004 China Beijing Simulation Center Science and Technology on Special System Simulation Laboratory Beijing100854 China

ISBN: (纸本)9798350338874

This paper presents a miniaturized TEM horn antenna for ground penetrating radar (GPR). First, an exponential gradient horn antenna is designed with a low cut-off frequency of 0.45 GHz. Then, the low cut-off frequency is decreased to 0.19 GHz through curve structural loading and lens loading without increasing the size of the horn. The antenna size is 378.49 mm × 359.07 mm × 386.06 mm, corresponding to 0.226 λ1 × 0.238 λ1 × 0.243 λ1 ( λ1 is the wavelength corresponding to the lowest frequency of the antenna). The results show that the working bandwidth of the antenna is 0.19-3GHz, and it has a good radiation pattern in the band, with a peak gain of 12.4dBi, which would be a good candidate for GPR. © 2023 IEEE.

关键词： Horn antennas

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A Light Source system of Multi-star Simulator with Adjustable Background and Controllable Magnitude

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空间科学学报 2017年第6期37卷 760-765页

作者： SUN Gaofei LIU Shi ZHANG Guoyu ZHANG Yu LEI Jie MA Yiyuan College of Optoelectronic Engineering Changchun University of Science and Technology Changchun 130022 Optical Measurement and Control Instrumentation Jilin Province Engineering Research Center Changchun 130022 Key Laboratory of Space System Simulation Beijing 100853

A light source of multi-star simulator capable of background adjustment and magnitude control has been *** integrating spheres are employed as the star-point light source and the background light source respectively.A beam splitter prism has been designed to serve as the beam combiner for the star-point and the background light sources,and a mathematical model has been constructed respectively to compute the light flux of the two integrating spheres.A magnitude testing system and a background testing system have been created using low-light illuminometer,luminance meter,and testing instruments to measure the star-point magnitude and the background luminance of the multi-star *** test results suggest that the star-point magnitude is adjustable from0 to+5 m_v,with a simulation precision superior to ±0.026 m_*** maximum background luminance is 3.8×10~5 cd·m^(-2),and the minimum background luminance is6.4×10^(-2)cd·m^(-2).The designed light source system can meet the requirements for simulating the stellar map with a sky background.

关键词： Adjustable background Controllable magnitude Multi-Star simulator Light source

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Analysis of node importance of satellite network based on triangular motif

Analysis of node importance of satellite network based on tr...

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2023 International Conference on Communication Network and Machine Learning, CNML 2023

作者： Pei, Zhongmin Hu, Boren Luo, Zhangkai Ding, Jie Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing101416 China Department of Electronics and Optical Engineering Space Engineering University Beijing101416 China

ISBN: (纸本)9798400716683

Motif provides a local high-order substructure angle for the analysis of network structure evolution, which is of great significance for the study of the interaction between satellite network structure and function. Taking the time scrambling null motif in steady state as a reference, the stability analysis of satellite network structure is carried out from the perspective of the local structure of the motif characteristics;define the temporal degree of satellite network, and propose a satellite network node importance analysis method based on the number of node-constructed triangle motifs, and compare the changes of motifs characteristics under the deliberate attack of temporal degree and based on triangle motifs. simulation experiments are conducted on 46-node GPS constellations containing satellites and ground stations, and it is found that the network with higher initial triangle concentration showed higher stability. In GPS satellite network where the number of node triangle motif is positively correlated with their temporal degree, the attack strategy based on the triangle motif accelerates the attenuation of the triangle subgraph, and the node importance analysis method of the satellite network has higher accuracy. © 2023 ACM.

关键词： Satellites

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simulation Experiment Factor Screening Method Based on Combinatorial Optimization 21st

Simulation Experiment Factor Screening Method Based on Combi...

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21st Asia simulation Conference, AsiaSim 2022

作者： Zhang, Peng Li, Wei Chen, Qingao Tong, Jiahui Control and Simulation Center Harbin Institute of Technology Harbin China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing China

ISBN: (纸本)9789811991974

When conducting complex simulation experiments, experimental factor screening is of great significance to improve the effectiveness and efficiency of the simulation. Aiming at the problems of unsatisfactory accuracy and efficiency of existing experimental factor screening methods, a simulation experiment factor screening method based on combinatorial optimization (EFS-CO) was designed. EFS-CO abstracts the experimental factor screening problem into a combinatorial optimization problem, designs the experimental factor evaluation criteria based on the support vector machine model, uses it as the fitness function of the genetic algorithm, and finally obtains the significant experimental factor. At the same time, to eliminate the influence of the randomness of the genetic algorithm on the screening results, the screening results of the experimental factors were determined based on the results of multiple experiments. Finally, the effectiveness of the method is verified by example analysis and comparing the results with the traditional experimental factor screening method. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Combinatorial optimization

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A practical approach for test equipment perception and virtualization in cloud manufacturing

A practical approach for test equipment perception and virtu...

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Chinese Intelligent systems Conference, CISC 2017

作者： Xu, Yuyan Zhang, Lin Luo, Xiao Zhang, Han School of Automation Science and Electrical Engineering Beihang University Beijing100191 China Engineering Research Center of Complex Product Advanced Manufacturing Systems Ministry of Education Beijing100191 China Science and Technology on Special System Simulation Laboratory Beijing Simulation Center Beijing100854 China

ISBN: (纸本)9789811064982

As an advanced manufacturing paradigm, Cloud Manufacturing provides a new way to solve the problems in the testing process. In cloud manufacturing, resource perception and resource virtualization are the foundation of building an actual service platform. According to the characteristic of test equipment, a practical approach for test equipment perception and virtualization is proposed, which is based on cloud computing, Automatic Test Markup Language (ATML) description and data mapping. A test service platform prototype is given to validate the feasibility of this approach. © 2018, Springer Nature Singapore Pte Ltd.

关键词： Virtualization

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Evaluating Metal-Support Interaction in Formaldehyde Oxidation Using Pd/TiO₂ Catalysts: The Key Role of Mono-Oxygen Vacancies

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Inorganic Chemistry 2025年 2025 May 14页

作者： Chen, Xudong Wang, Chunying Wang, Jingyi Wen, Wei Liu, Xiaofeng Li, Yaobin Shan, Wenpo He, Hong Center for Excellence in Regional Atmospheric Environment Key Laboratory of Urban Pollutant Conversion Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China Zhejiang Key Laboratory of Pollution Control for Port-Petrochemical Industry Ningbo Urban Environment Observation and Research Station Institute of Urban Environment Chinese Academy of Sciences Ningbo 315800 China School of Resources & Chemical Engineering Sanming University Sanming 365004 China Faculty of Environmental Science and Engineering Kunming University of Science and Technology Kunming 650000 China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China University of Chinese Academy of Sciences Beijing 100049 China

Metal-support interactions (MSI) have been widely recognized as playing a key role in regulating the catalytic activity in various reactions. However, clarifying the relationship linking catalyst defect structures, active sites, and catalytic performance for catalysts with a constructed MSI remains a challenge. Here, Pd/TiO₂ catalysts with adjustable MSI were designed and fabricated based on defect engineering. Comprehensive characterization analysis revealed that as the catalyst reduction temperature and defect content increase, the MSI gradually increases, subsequently enhancing the intrinsic activity of the catalyst to oxidize formaldehyde (HCHO). However, the activity of the catalyst exhibited a volcano-shaped trend, which was caused by the collapse of the support structure at a high reduction temperature. Through comparative analysis of the HCHO oxidation reaction and CO oxidation reaction activity tests, it was confirmed that the ratio of mono-oxygen vacancies to oxygen vacancy clusters (I₁/I₂) in this study system could reliably serve as a valid “descriptor” for HCHO oxidation apparent activity. © 2025 American Chemical Society.

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Research on starlight hardware-in-the-loop simulator

Research on starlight hardware-in-the-loop simulator

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International Symposium on Optoelectronic technology and Application 2016(OTA 2016)——Conf.5 Optical Measurement technology and Instrument

作者： ZHANG Ying GAO Yang LIU Dongfang DU Huijie LEI Jie Science and Technology on Special System Simulation Laboratory Beijing Simulation Center

The starlight navigation is considered one of the most essential methods for spacecraft *** simulation system is a high-precision system with large fields of view and is designed to t

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Enhanced secondary pollution offset reduction of primary emissions during COVID-19 lockdown in China

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National science Review 2021年第2期8卷 51-59页

作者： Xin Huang Aijun Ding Jian Gao Bo Zheng Derong Zhou Ximeng Qi Rong Tang Jiaping Wang Chuanhua Ren Wei Nie Xuguang Chi Zheng Xu Liangduo Chen Yuanyuan Li Fei Che Nini Pang Haikun Wang Dan Tong Wei Qin Wei Cheng Weijing Liu Qingyan Fu Baoxian Liu Fahe Chai Steven J.Davis Qiang Zhang Kebin He School of Atmospheric Sciences Nanjing University Chinese Research Academy of Environmental Sciences Department of Earth System Science Tsinghua University State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua University Department of Earth System Science University of California Jiangsu Environmental Monitoring Center Jiangsu Provincial Academy of Environment Science Shanghai Environmental Monitoring Center Beijing Key Laboratory of Airborne Particulate Matter Monitoring Technology Beijing Municipal Environmental Monitoring Center

To control the spread of the 2019 novel coronavirus(COVID-19), China imposed nationwide restrictions on the movement of its population(lockdown) after the Chinese New Year of 2020, leading to large reductions in economic activities and associated emissions. Despite such large decreases in primary pollution, there were nonetheless several periods of heavy haze pollution in eastern China, raising questions about the well-established relationship between human activities and air quality. Here, using comprehensive measurements and modeling, we show that the haze during the COVID lockdown was driven by enhancements of secondary pollution. In particular, large decreases in NOx emissions from transportation increased ozone and nighttime NO3radical formation, and these increases in atmospheric oxidizing capacity in turn facilitated the formation of secondary particulate matter. Our results, afforded by the tragic natural experiment of the COVID-19 pandemic, indicate that haze mitigation depends upon a coordinated and balanced strategy for controlling multiple pollutants.

关键词： COVID-19 haze pollution ozone emission reduction secondary pollution

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Fast direct solution of 3-D dynamic electromagnetic problems by method of moments

Fast direct solution of 3-D dynamic electromagnetic problems...

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Antennas and Propagation Society International Symposium

作者： Yan-Nan Liu Ming-Ming Xu Xiao-Min Pan Xin-Qing Sheng Cong-Jun Jin Center for Electromagnetic Simulation Beijing Institute of Technology Beijing China Science and Technology on Space System Simulation Laboratory Beijing China

The direct solver based on skeletonization consists of two stages: selecting skeletons and computing the inverse matrix. The selection of skeletons can be expensive although Huygens' principle is employed to avoid filling in the complete impedance matrix. A fast matrix filling strategy is proposed to alleviate the difficulty by making use of Taylor series. Numerical experiments indicate the proposed method can significantly accelerate the matrix filling process with no loss in accuracy.

关键词： Skeleton Method of moments Taylor series Electromagnetics Impedance Matrix decomposition Integral equations

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A credibility allocation approach of complex simulation systems 35

A credibility allocation approach of complex simulation syst...

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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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