检索结果-内蒙古大学图书馆

Multiplexed model predictive attitude control for nadir-pointing satellite using only magnetorquers

Control Engineering Practice 2025年 162卷

作者： Yang, Sen Ling, Keck Voon Wang, Zhenhua Li, Huiping School of Astronautic Harbin Institute of Technology Harbin150001 China School of Electrical and Electronic Engineering Nanyang Technological University Singapore639798 Singapore National Key Laboratory of Complex System Control and Intelligent Agent Cooperation Harbin150001 China School of Marine Science and Technology Northwestern Polytechnical University Xi'an710072 China

Due to the low failure risk of magnetorquers, the control strategy based on magnetic actuators can significantly enhance the reliability of the satellite attitude control system. In light of this advantage, this paper conducts research on model predictive control (MPC) algorithm for nadir-pointing satellites equipped only with magnetorquers. Firstly, to facilitate controller design, the linear time-varying (LTV) model for nadir-pointing satellites is derived by linearizing the nonlinear equations around the operating point. Then, leveraging this linearized representation, an LTV multiplexed MPC (MMPC) method with exponential weighting is proposed. The MMPC scheme allows for faster sampling rates and quicker responses to disturbances, thereby enhancing the overall performance of the satellite attitude control system while retaining the benefits of MPC. Finally, compared with a state-of-the-art SMPC method, the proposed method is particularly advantageous in situations where computational resources are limited, specifically for satellites that rely only on onboard computing capabilities. © 2025

关键词： Nonlinear equations

来源：评论

学校读者我要写书评

暂无评论

A General Framework for Chinese Domain Knowledge Graph Question Answering Based on TransE 3

A General Framework for Chinese Domain Knowledge Graph Quest...

引用

2020 3rd International Conference on Computer Information science and Artificial Intelligence, CISAI 2020

作者： Pei, Zhongmin Zhang, Jie Xiong, Wei Li, Li Luo, Zhangkai Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China Gaojing Network Management and Security Center Beijing China

This paper introduces a general question answering (QA) framework for Chinese domain knowledge graphs to serve various industries. The question is analyzed by shielding invalid characters in this framework, and the TransE calculation of entities and relations is used to search answer, rather than traditional logical queries that rely heavily on predefined rules. In this way, the QA framework can be easily applied to different fields with little manual participation, and reduce the migration cost caused by the lack of scalability of the existing QA systems, which are designed only for specific domains. Then, the proposed framework is operated on the space launch knowledge graph and has achieved HITS@1, HITS@3, HITS@5 scores of 60.60%, 80.87%, 85.61% separately, which is competitive with other restricted domain knowledge graphs. In addition, numerical results on the knowledge graph of the Three Kingdoms and the COVID-19-Character verified the scalability of the QA framework. © Published under licence by IOP Publishing Ltd.

关键词： Knowledge graph

来源：评论

学校读者我要写书评

暂无评论

Photocatalytic Degradation of Tetracycline Over Bimetallic Layered Double Hydroxides-Mxenes Heterostructures Under Visible Light

SSRN

引用

SSRN 2024年

作者： Yao, Jixin Liu, Yong Tong, Xiaowei Lu, Shibin Meng, Ying Li, Guang Anhui Province Key Laboratory of Simulation and Design for Electronic Information System Universities Joint Key Laboratory of Photoelectric Detection Science and Technology in Anhui Province Hefei Normal University Hefei230601 China School of Materials Science and Engineering Anhui Key Laboratory of Information Materials and Devices Key Laboratory of Structure and Functional Regulation of Hybrid Materials Ministry of Education Institute of Physical Science and Information Technology Anhui University Hefei230601 China School of Electronic Engineering Huainan Normal University Huainan232038 China

Layered double hydroxides (LDHs) are widely used in photocatalytic degradation of antibiotic pollutants under ultraviolet (UV)-light, but their efficiency under visible light is hampered by large band gaps and layer agglomeration. To address these challenges, we have successfully developed innovative bimetallic NiCo LDHs-MXenes heterostructures (LDHs-MXenes) for enhanced degradation of tetracycline (TC) pollutants under visible light conditions. As-prepared LDHs-MXenes photocatalysts (20 mg) show exceptional performance, achieving ~97.4% TC degradation efficiency (20 mg L-1, 100 mL) within just 50 minutes under a 300 W Xe lamp. This significant enhancement underscores the synergistic effects derived from the combination of LDHs and MXenes nanosheets. © 2024, The Authors. All rights reserved.

关键词： Heterojunctions

来源：评论

学校读者我要写书评

暂无评论

Analysis of overload-based cascading failure in multilayer spatial networks

引用

Chinese Physics B 2020年第9期29卷 404-414页

作者： Min Zhang Xiao-Juan Wang Lei Ji Mei Song Zhong-Hua Liao School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Complex Product Advanced Manufacturing Engineering Research Center Beijing Simulation CenterBeijing 100854China State Key Laboratory of Intelligent Manufacturing System Technology Beijing Institute of Electronic System EngineeringBeijing 100854China

Many complex networks in real life are embedded in space and most infrastructure networks are interdependent,such as the power system and the transport *** this paper,we construct two cascading failure models on the multilayer spatial *** our research,the distance l between nodes within the layer obeys the exponential distribution P(l)~exp(-l/ζ),and the length r of dependency link between layers is defined according to node *** entropy approach is applied to analyze the spatial network structure and reflect the difference degree between *** metrics,namely dynamic network size and dynamic network entropy,are proposed to evaluate the spatial network robustness and *** the cascading failure process,the spatial network evolution is analyzed,and the numbers of failure nodes caused by different reasons are also counted,***,we discuss the factors affecting network *** demonstrate that the larger the values of average degree,the stronger the network *** the length r decreases,the network performs *** the probability p is small,asζdecreases,the network robustness becomes more *** p is large,the network robustness manifests better performance asζ*** results provide insight into enhancing the robustness,maintaining the stability,and adjusting the difference degree between nodes of the embedded spatiality systems.

关键词： cascading failure multilayer network load distribution spatial network entropy

来源：评论

学校读者我要写书评

暂无评论

An SIE Formulation With Loop Analysis for Large-Scale Arbitrarily Shaped Interconnects

An SIE Formulation With Loop Analysis for Large-Scale Arbitr...

引用

Antennas and Propagation Society International Symposium

作者： Zekun Zhu Ningbo Gong Guijie Diao Shunchuan Yang School of Electronic and Information Engineering Beihang University Beijing China Beijing Electro-mechanical Engineering Institute Beijing China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory China

A magneto-quasi-static (MQS) surface integral equation (SIE) formulation with loop analysis is proposed to extract the impedance of interconnects in packages. The loop analysis is developed with an independent and complete set of unknowns according to the graph theory, which can significantly reduce the dimension of the final matrix. With the pre-corrected fast Fourier Transform (pFFT), large-scale interconnects can be efficiently modelled. A practical example in packages is carried out to validate the effectiveness and scalability of the proposed formulation. Results show that the proposed formulation is accurate and flexible to model complex interconnects in packages compared with the industrial solver.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Research on the Scattering Characteristics of the Van Atta Cube Scatterer

Research on the Scattering Characteristics of the Van Atta C...

引用

International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Lin Gan Zehao Wu Jianbing Li The State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System College of Electronic Science and Technology National University of Defense Technology Changsha China

In order to realize good omnidirectional backtracking of electromagnetic waves, a Van Atta cube scatterer consists of six identical Van Atta plane arrays is proposed. In this paper, the scattering characteristics in different incident directions are emphatically studied. simulation results show that the Van Atta cube scatterer has the advantage of omnidirectional scattering, with the effective backtracking angle range exceeding 77% of the whole angle domain.

关键词： Backtracking Interference cancellation simulation Electromagnetic scattering Computational electromagnetics Optimization Antenna arrays

来源：评论

学校读者我要写书评

暂无评论

A Rapid Evaluation Method of Radar Tracking Accuracy 20

A Rapid Evaluation Method of Radar Tracking Accuracy

引用

Proceedings of the 2020 4th International Conference on electronic Information technology and Computer Engineering

作者： Zhongwen Zhao Xu Zhang Guodong Li Science and Technology on Complex Electronics System Simulation Laboratory Space Engineering University Beijing China

ISBN: (纸本)9781450387811

In order to solve the problem that the accuracy evaluation method based on error grouping is complex and can only be applied to post-processing, a fast judgment analysis method of radar tracking accuracy is proposed. This method decouples the two main processes of accuracy evaluation, namely error estimation and error statistics, and achieves fast analysis of radar tracking accuracy through real-time estimation of local accuracy and fast statistics of average accuracy of whole track. At the same time, this method avoids the discrimination of abnormal errors by applying robust median and median absolute difference estimation, further simplifies the error estimation process, so that it is more suitable for real-time data analysis.

关键词： Accuracy Evaluation Error Grouping Radar Robust Rapid Evaluation

来源：评论

学校读者我要写书评

暂无评论

Recognition of Continuous Phase Modulation Signals Based on Synchrosqueezing Wavelet Transform

Recognition of Continuous Phase Modulation Signals Based on ...

引用

International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Guangxin Ruan Liu Zhao Zheng Liu State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System College of Electronic Science and Technology National University of Defense Technology Changsha China

We present a new algorithm that can solve the problem of recognition of continuous phase modulation (CPM) signals to phase shift keying (PSK) signals. The algorithm uses synchrosqueezing wavelet transform (SWT) to extract the instantaneous frequency (IF) of the signal. On this basis, a recognition characteristic parameter is proposed. This paper verifies the parameter is suitable for PSK and CPM signals with different modulation parameters. Finally, the simulation shows that the algorithm can fully recognize CPM signals to BPSK and QPSK signals when signal-to-noise ratio (snr) is above 6dB. Compared with the existing algorithms, the algorithm proposed in this paper has a higher recognition rate in the low snr environment.

关键词： Phase shift keying Frequency modulation Continuous wavelet transforms Computational modeling Computational electromagnetics Discrete wavelet transforms Binary phase shift keying

来源：评论

学校读者我要写书评

暂无评论

Pulse Signal Denoising Method Based on Frequency Domain Wavelet Transform

Pulse Signal Denoising Method Based on Frequency Domain Wave...

引用

International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Zhao Liu Guangxin Ruan Zheng Liu State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System College of Electronic Science and Technology National University of Defense Technology Changsha China

Bandpass filtering and time-domain wavelet threshold denoising methods do not perform well in pulse signal denoising, which are not effective for Specific Emitter Identification (SEI). Base on this problem, we propose a frequency-domain wavelet threshold denoising method, and improve the threshold estimation method as well as threshold function. simulation results show that the proposed method is more superior than traditional methods in restoring the envelope and instantaneous frequency of the single-frequency pulse signals, which proves that our method has the potential to improve the accuracy of SEI.

关键词： Wavelet transforms Wavelet domain Filtering Frequency-domain analysis simulation Noise reduction Estimation

来源：评论

学校读者我要写书评

暂无评论

Periodically-coded ITR Modulation Characteristics of PCM Signal in Radar Radiation simulation

Periodically-coded ITR Modulation Characteristics of PCM Sig...

引用

International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Tiehua Zhao Qihua Wu Xiaobin Liu Xiaofeng Ai Feng Zhao Shunping Xiao The State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System College of Electronic Science and Technology National University of Defense Technology Changsha China

The overlapping and mutual coupling between transmitting and receiving signals is a knotty problem in radar radiation simulation. Interrupted transmitting and receiving (ITR) modulation can effectively solve this problem caused by limited space of the microwave chamber. In order to further expand the application of ITR modulation method, the characteristics of periodically-coded interrupted modulation signals are analyzed in this paper. Focusing on the modulated pulse coded modulation (PCM) signal, the time-frequency domain characteristics and matched filter output characteristics are studied in detail. Signal simulation experiments are carried out with MATLAB to verify the accuracy of the theoretical analysis.

关键词： Analytical models Time-frequency analysis Matched filters Mutual coupling Focusing Radar Microwave theory and techniques

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：