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A fast calculation method for three-impulse contingency return trajectory during the near-moon phase based on differential algebra

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Chinese Journal of Aeronautics 2025年第04期 290-308页

作者： Lin LU Haiyang LI Tianshan DONG Wanmeng ZHOU College of Aerospace Science and Technology National University of Defense Technology Hunan Key Laboratory of Intelligent Planning and Simulation for Aerospace Missions Beijing Institute of Spacecraft System Engineering China Astronaut Research and Training Center

Aimed at the demand of contingency return at any time during the near-moon phase in the manned lunar landing missions,a fast calculation method for three-impulse contingency return trajectories is ***,a three-impulse contingency return trajectory scheme is presented by combining the Lambert transfer and maneuver at the special ***,a calculation model of three-impulse contingency return trajectories is ***,fast calculation methods are proposed by adopting the high-order Taylor expansion of differential algebra in the twobody trajectory dynamics model and perturbed trajectory dynamics ***,the performance of the proposed methods is verified by numerical *** results indicate that the fast calculation method of two-body trajectory has higher calculation efficiency compared to the semi-analytical calculation method under a certain accuracy *** to its high efficiency,the characteristics of the three-impulse contingency return trajectories under different contingency scenarios are further analyzed *** findings can be used for the design of contingency return trajectories in future manned lunar landing missions.

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High Abundance of Atmospheric Sulfonates Derived from Light-Duty Gasoline Vehicles

ACS ES&T Air

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ACS ES&T Air 2025年第4期2卷 607-614页

作者： Shuang Chen Huixia Han Lihong Ren Yisheng Xu Libin Wu Yuanguan Gao Yuanbi Yi Xinping Yang Mingliang Fu Hang Yin Yan Ding Pingqing Fu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Beijing 100012 China；School of Earth System Science Tianjin University Tianjin 300072 China School of Earth System Science Tianjin University Tianjin 300072 China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Beijing 100012 China Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau The Hong Kong University of Science and Technology Hong Kong SAR China State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation Chinese Research Academy of Environmental Sciences Beijing 100012 China

Particulate matter (PM) emissions from light-duty gasoline vehicles (LDGV) pose a threat to both air quality and human health. However, the molecular compositions and chemical properties of these complex mixtures are poorly understood. In this study, we performed a detailed characterization of exhaust PM from LDGV at various speed phases at the molecular level by employing ultra-high-resolution Fourier transform ion cyclotron resonance mass spectrometry. We found that with increasing speed, the number of organic compounds increased significantly, especially organic nitrogen-containing and sulfur-containing compounds. Moreover, the increase of speed leads to high temperature and high pressure in the cylinder, which in turn leads to a series of thermal cracking–polymerization–cyclization reactions, resulting in new particulate matter with more aromatic structures. In addition, considerable intermediate volatility organic compounds and semivolatile organic compounds were identified in the exhaust PM. Notably, we observed the presence of sulfonates in tailpipe particulate matter during low- or high-speed phases, which highlights a previously negligible source of organic sulfonates in the atmosphere.

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Diffusion mechanism simulation of cloud manufacturing complex network based on cooperative game theory

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Journal of systems Engineering and Electronics 2018年第2期29卷 321-335页

作者： GENG Chao QU Shiyou XIAO Yingying WANG Mei SHI Guoqiang LIN Tingyu XUE Junjie JIA Zhengxuan Economics and Management School Harbin Institute of Technology at Weihai Beijing Complex Product Advanced Manufacturing Engineering Research Center Beijing Simulation Center State Key Laboratory of Intelligent Manufacturing System Technology Beijing Institute of Electronic System Engineering Science and Technology on Space System Simulation Laboratory Beijing Simulation Center

Cloud manufacturing is a specific implementation form of the "Internet + manufacturing" strategy. Why and how to develop cloud manufacturing platform(CMP), however, remains the key concern of both platform operators and users. A microscopic model is proposed to investigate advantages and diffusion forces of CMP through exploration of its diffusion process and mechanism. Specifically, a three-stage basic evolution process of CMP is innovatively proposed. Then, based on this basic process, a more complex CMP evolution model has been established in virtue of complex network theory, with five diffusion forces identified. Thereafter, simulations on CMP diffusion have been conducted. The results indicate that, CMP possesses better resource utilization,user satisfaction, and enterprise utility. Results of simulation on impacts of different diffusion forces show that both the time required for CMP to reach an equilibrium state and the final network size are affected simultaneously by the five diffusion forces. All these analyses indicate that CMP could create an open online cooperation environment and turns out to be an effective implementation of the "Internet + manufacturing" strategy.

关键词： complex network cloud manufacturing innovation diffusion network effect Gale-Shapley algorithm cooperative game theory

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Scattering Center Modeling Using Adaptive Segmental Compressive Sampling

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Journal of Beijing Institute of technology 2017年第4期26卷 484-493页

作者： Qifeng Li Kunyi Guo Jiaxin Wang Xinqing Sheng Tianshu Liu Center for Electromagnetic Simulation School of Information and ElectronicsBeijing Institute of Technology Science and Technology on Special System Simulation Laboratory Beijing Simulation Center

In order to deal with aliasing distortions of Doppler frequencies shown in time-frequency representation（ TFR） with aspect undersampling,an approach using adaptive segmental compressive sampling according to the aspect dependencies of the scattering centers is proposed. The random noise problem induced by compressive sampling is solved by employing a series of signal processing techniques of filtering,image transformation and Hough Transform. Three examples are presented to verify the effectiveness of this approach. The comparisons between the built models and the precise scattered fields computed by a well-validated full-wave numerical method are investigated,and the results showgood agreements between each other.

关键词： scattering center undersampling compressive sensing time-frequency representation parameter estimation

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Symplectic Wigner Distribution in the Linear Canonical Transform Domain: Theory and Application

arXiv

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arXiv 2025年

作者： He, Yangfan Zhang, Zhichao School of Communication and Artificial Intelligence School of Integrated Circuits Nanjing Institute of Technology Nanjing211167 China School of Mathematics and Statistics Nanjing University of Information Science and Technology Nanjing210044 China Key Laboratory of System Control and Information Processing Ministry of Education Shanghai Jiao Tong University Shanghai200240 China Key Laboratory of Computational Science Application of Hainan Province Hainan Normal University Haikou571158 China Key Laboratory of Numerical Simulation of Sichuan Provincial Universities School of Mathematics and Information Sciences Neijiang Normal University Neijiang641000 China

This paper devotes to combine the chirp basis function transformation and symplectic coordinates transformation to yield a novel Wigner distribution (WD) associated with the linear canonical transform (LCT), named as the symplectic WD in the LCT domain (SWDL). It incorporates the merits of the symplectic WD (SWD) and the WD in the LCT domain (WDL), achieving stronger capability in the linear frequency-modulated (LFM) signal frequency rate feature extraction while maintaining the same level of computational complexity. Some essential properties of the SWDL are derived, including marginal distributions, energy conservations, unique reconstruction, Moyal formula, complex conjugate symmetry, time reversal symmetry, scaling property, time translation property, frequency modulation property, and time translation and frequency modulation property. Heisenberg’s uncertainty principles of the SWDL are formulated, giving rise to three kinds of lower bounds attainable respectively by Gaussian enveloped complex exponential signal, Gaussian signal and Gaussian enveloped chirp signal. The optimal symplectic matrices corresponding to the highest time-frequency resolution are generated by solving the lower bound optimization (minimization) problem. The time-frequency resolution of the SWDL is compared with those of the SWD and WDL to demonstrate its superiority in LFM signals time-frequency energy concentration. A synthesis example is also carried out to verify the feasibility and reliability of the theoretical analysis. Copyright © 2025, The Authors. All rights reserved.

关键词： Wigner-Ville distribution

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A Large-Scale Scheduling Method for Multiple Agile Optical Satellites

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Computer Modeling in Engineering & sciences 2023年第8期136卷 1143-1163页

作者： Zheng Liu Wei Xiong Minghui Xiong Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering UniversityBeijing101416China

This study investigates the scheduling problem ofmultiple agile optical satelliteswith large-scale *** problem is difficult to solve owing to the time-dependent characteristic of agile optical satellites,complex constraints,and considerable solution *** solve the problem,we propose a scheduling method based on an improved sine and cosine algorithm and a task merging *** first establish a scheduling model with task merging constraints and observation action constraints to describe the ***,an improved sine and cosine algorithm is proposed to search for the optimal solution with the maximum profit *** adaptive cosine factor and an adaptive greedy factor are adopted to improve the ***,a taskmerging method with a task reallocation mechanism is developed to improve the scheduling *** results demonstrate the superiority of the proposed algorithm over the comparison algorithms.

关键词： Multiple agile optical satellites scheduling task merging sine and cosine algorithm task reallocation

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A Service Mining Scheme Based on Semantic for Internet of Things

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Chinese Journal of Electronics 2014年第2期23卷 236-242页

作者： LI Xinming SUN Yan The Science and Technology on Complex Electronic System Simulation Laboratory Academy of Equipment The School of Computer Science Beijing University of Posts and Telecommunication

As the development of Internet of things(IOT), massive sensors have been deployed as the public infrastructure. With the development of in-depth applications in IOT, service discovery and composition are challenges to the end users. To handle this challenge, we develop a service mining scheme based on semantic for IOT to provide users with interesting composite services. In this scheme, services can be combined and recommended to users actively according to the calculation of service similarity and an updatable semantic database. By the results of service similarity, useless compositions can be filtered out so that energy consumption on service flooding will be reduced. The update strategy of semantic database is also given out, by which the composite services can keep up with time and be more applicative. The benefits of the proposed method are that all operations such as calculating, filtering, and updating are simple enough to be performed in sensor networks.

关键词： Internet of things Service mining Semantic database Service similarity Service composition

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Research on Credibility Evaluation for Radio Frequency Guided Hardware-In-the-Loop simulation system 36

Research on Credibility Evaluation for Radio Frequency Guide...

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第36届中国控制会议

作者： Yuxiao Wang Tao Chao Chaolei Wang Songyan Wang Harbin Institute of Technology Science and Technology on Special System Simulation Laboratory Beijing Simulation Center

ISBN: (纸本)9781538629185

To ensure the effectiveness of the RF（Radio Frequency） guided HILS（Hardware-In-the-Loop simulation） system,the credibility evaluation was *** present,most of the methods were applied in the case of the simulation system input being consistent with the real system input,which is difficult to achieve in some subsystem of the RF guided HILS *** this paper,the relative complete system reliability evaluation index system was *** were classified,for different categories of subsystem,corresponding reliability assessment methods were *** particular,reliability evaluation methods based on performance level were put forward,when certain subsystems cannot be evaluated by consistency analysis methods.A simple example was given to show the evaluation process.

关键词： Radio Frequency Guided Hardware-In-the-Loop simulation Credibility Evaluation Index system Performance Index

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Long-term effects of PM2.5 constituents on childhood attention deficit hyperactivity disorder: evidence from a large population-based study in the Pearl River Delta Region, China

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Environmental Research 2025年 277卷 121641页

作者： Zeng, Hui-Xian Meng, Wen-Jie Zeng, Qing-Guo Wei, Jing Liu, Lu-Sheng Wu, Qi-Zhen Zhao, Bin Oudin, Anna Yang, Mo Jalava, Pasi Dong, Guang-Hui Zeng, Xiao-Wen Joint International Research Laboratory of Environment and Health Ministry of Education Guangdong Provincial Engineering Technology Research Center of Environmental Pollution and Health Risk Assessment Department of Occupational and Environmental Health School of Public Health Sun Yat-sen University Guangzhou510080 China Department of Atmospheric and Oceanic Science Earth System Science Interdisciplinary Center University of Maryland College ParkMD United States State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Tsinghua University Beijing100084 China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing100084 China Department of Public Health and Clinical Medicine Umeå University Umeå Sweden Department of Environmental and Biological Science University of Eastern Finland Kuopio Finland

Background: Evidence linking fine particulate matter (PM2.5) constituents to childhood attention deficit hyperactivity disorder (ADHD) was limited. Objectives: To investigate the individual and joint effects of exposure to PM2.5 constituents on ADHD. Methods: We conducted a large population-based survey involving 110,818 school children aged 6–18 years across six cities in the Pearl River Delta region, China. The three-year average concentrations of PM2.5 constituents (black carbon (BC), organic matter (OM), sulfate, nitrate, and ammonium) were estimated using the ChinaHighAirPollutants dataset. Parents completed an ADHD checklist using the Diagnostic and Statistical Manual of Mental Disorders-IV criteria. The individual and joint associations between PM2.5 components and ADHD were estimated using generalized linear mixed models and the quantile g-computation regression model, respectively. Results: The exposure-response relationships between PM2.5 constituents and ADHD primarily exhibited a nonlinear pattern. Compared with the lowest tertile, the highest tertiles of PM2.5 and its components were linked to greater odds for ADHD (e.g., the adjusted odds ratio (OR) was 1.37 (95 % confidential interval (CI): 1.27, 1.47) for PM2.5, 1.51 (95 %CI: 1.40, 1.63) for OM, 1.29 (95 %CI: 1.20, 1.39) for BC, and 1.20 (95 %CI:1.08, 1.34) for sulfate). Similar positive associations were observed between BC and sulfate exposure and ADHD subtypes. Moreover, joint exposure to PM2.5 components was associated with ADHD (OR = 1.14, 95 % CI:1.10, 1.18), with OM and BC contributing more to the observed associations. Conclusions: These findings highlight the varying contributions of PM2.5 constituents to ADHD and underscore the importance of reducing specific PM2.5 component emissions to mitigate the burden of PM2.5-associated neurodevelopmental diseases. © 2025 Elsevier Inc.

关键词： Regression analysis

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A Phase Unwrapping Method for Large Scale Interferometric Phase Images 2017

A Phase Unwrapping Method for Large Scale Interferometric Ph...

引用

Proceedings of the International Conference on Imaging, Signal Processing and Communication

作者： Hao Hongxing Wu Lingda Song Xiaorui Science and Technology on Complex Electronic System Simulation Laboratory Equipment Academy

ISBN: (纸本)9781450352895

Optical interferometry images are widely used in many research areas such as geoscience and remote sensing. However, the phase image which gets from the sensors is modulo-2π, and an important process is to estimate the absolute phase from the observation which is termed phase unwrapping. This paper addresses the absolute phase estimation of large scale images. The proposed phase unwrapping method is patch based which divides the large interferogram into small patches and does the unwrapping based on Markov Random Field for each small patch. This paper also analyzes the two types of errors that may be caused in the combination of the patches and studies how to get rid of these errors. The advantage of the proposal is that the method can be used for the wrapped phase images with discontinuous areas. Experiments in the paper show the efficiency of the proposed algorithm.

关键词： Phase Unwrapping InSAR image processing Remote sensing Digital Elevation Model data

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