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30th International Conference on Computational and Experimental Engineering and Sciences, ICCES 2024

作者： Zhang, Tao Lu, Yu Li, Jun Wang, Biao Zhan, Jiahao Beijing Key Laboratory of High Dynamic Navigation Technology Beijing Information Science and Technology University Beijing100101 China China University of Petroleum Beijing102249 China

ISBN: (纸本)9783031829062

With the deepening of oil and gas resources development, there are more and more large inclined wells, horizontal wells and long horizontal wells. The error between the real force of drilling tools at the near bit and the calculation results relying on wellhead data is large. Adopting drill collar radial drilling, spatial reuse structure, and strain measurement method, a 0.3-m-long, 178-mm outside diameter tool was designed to measure engineering parameters such as weight on bit (WOB), torque, rotational speed, and fluid pressure. Through the field test, the pipe sticking data of the drilling tools near the bit were obtained, and the real stress situation was understood. Knowing the real stress condition of the drilling tools near the bit can help timely predict the complex working conditions of the well, optimize the drilling design and operation, improve the drilling safety and drilling efficiency, and enhance the drilling quality. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.

关键词： Horizontal wells

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Research on the navigation method of high speed differential rotation guided ammunition with ballistic assistance prediction under GNSS denial

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Defence technology 2025年

作者： Liu, Ning Hu, Kejun Hu, Bin Li, Haorui Shen, Kai Qi, Wenhao Fan, Junfang Su, Zhong Beijing Key Laboratory of High Dynamic Navigation Technology Beijing Information Science and Technology University Beijing100192 China Integrated Navigation and Intelligent Navigation Laboratory Beijing Institute of Technology Beijing100081 China

In complex environments such as high dynamics and weak signals, a satellite signal compensation method based on prefabricated trajectory assistance and an improved adaptive Kalman filter is proposed for a 155 mm differential rotating rear-body control-guided projectile to address the situation of satellite signal flickering and loss in projectile navigation systems due to environmental limitations. First, establish the system state and measurement equation when receiving satellite signals normally. Second, a seven-degree-of-freedom external ballistic model is constructed, and the ideal trajectory output from the ballistic model is used to provide the virtual motion state of the projectile, which is input into a filter as a substitute observation when satellite signals are lost. Finally, an adaptive Kalman filter (AKF) is designed, the proposed adaptive Kalman filter can accurately adjust the estimation error covariance matrix and Kalman gain in real-time based on information covariance mismatch. The simulation results show that compared to the classical Kalman filter, it can reduce the average positioning error by more than 38.21% in the case of short-term and full-range loss of satellite signals, providing a new idea for the integrated navigation of projectiles with incomplete information under the condition of satellite signal loss. © 2025 China Ordnance Society

关键词： Adaptive filters

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S3A: A Self-Supervised Saliency Analysis Framework for Hyperspectral Image

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IEEE Transactions on Geoscience and Remote Sensing 2025年 63卷

作者： Luo, Xiaoyan Zhang, Lei Gan, Peixin Shi, Xiaofeng Bian, Liheng Beihang University School of Astronautics Beijing100191 China National Key Laboratory of Integrated Air-Ground Navigation Technologies National Key Laboratory of High-Efficiency Earth-Space Round-Trip Transportation Technologies China National Key Laboratory of High-Efficiency Earth-Space Round-Trip Transportation Technologies China Beihang University School of Electronic Information Engineering Beijing100191 China National Key Laboratory of Integrated Air-Ground Navigation Technologies China Beijing Institute of Technology School of Information and Electronics Beijing100081 China

Most existing visual saliency analysis methods are meticulously crafted for natural RGB images, which typically lean upon foundational spatial visual cues, such as contrast, structure and texture in scenes. However, these methods exhibit limitations in spectral saliency analysis due to the existence of numerous materials that may manifest identical RGB values while harboring disparate spectral characteristics. Consequently, it is an exigency to introduce saliency method specially for hyperspectral images (HSIs). In this paper, we establish a set of hyperspectral saliency principles that incorporate both spectral and spatial attributes, and accordingly present a novel self-supervised saliency analysis (S3A) framework for HSIs. Note that our S3A is designed as a discriminant architecture composed of three interconnected components. More specifically, an unsupervised HSI representive patch sampling (RPS) module is designed to pick up some representative pixels for self-supervised saliency analysis training. Subsequently, we construct a classification-based patch spectral discrimination network (CPSD-Net) to evaluate the HSI saliency. Finally, a patch-to-global spatial diffusion (P2G-SD) module is constructed to diffuse the saliency from few supervised samples to the other HSI pixels. Moreover, to demonstrate the performance of our saliency analysis framework, we apply the HSI saliency to some classic downstream tasks including band selection (BS) and HSI classification. On several popular HSI datasets, the satisfactory quantization results fully verify the rationality and effectiveness of our S3A framework, in terms of entropy value and mean spectral divergence (MSD) of the selected bands in BS task, as well as the accuracy in HSI classification task. © 1980-2012 IEEE.

关键词： Support vector machines

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Distributed secure fusion estimation for multi-sensor systems in complex environment

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Zhongguo Guanxing Jishu Xuebao/Journal of Chinese Inertial technology 2025年第3期33卷 301-308页

作者： Qiu, Haitao Li, Yuxuan Zhu, Cui Beijing Key Laboratory of High Dynamic Navigation Technology Beijing Information Science & Technology University Beijing102206 China Beijing Jingwei Hirain Technologies Co. Inc Beijing100191 China School of Information and Communication Engineering Beijing Information Science & Technology University Beijing102206 China

A distributed secure fusion estimation algorithm with event-triggering is proposed for linear time-invariant multi-sensor systems in complex environment with spoofing attacks and limited channel resources. The event-triggered mechanism proceeds to decide whether the local estimation is updated and sent to the fusion center based on the innovation in the measurement and attack detection requirements. The adaptive threshold, which can adjust according to the predetermined false alarm rate and event trigger rate, is designed at the same time. On this basis, a distributed secure fusion estimation algorithm is proposed, and the boundedness of global estimation error is proved. To verify the effectiveness of the proposed algorithm, simulation experiments have been conducted. The experimental results show that, compared with the fusion estimation algorithm without considering the event-triggered mechanism and the fusion estimation algorithm based on the standard Chi-square detection, the average estimation accuracy of the proposed algorithm for horizontal and vertical positions is increased by 50%, 63%, 45% and 34%, 46%, 28%, respectively. © 2025 Editorial Department of Journal of Chinese Inertial technology. All rights reserved.

关键词： event-triggered fusion estimation multi-sensor system spoofing attack

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Recent progress on surface chemistryⅡ:Property and characterization

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Chinese Chemical Letters 2025年第1期36卷 8-57页

作者： Xin Li Zhen Xu Donglei Bu Jinming Cai Huamei Chen Qi Chen Ting Chen Fang Cheng Lifeng Chi Wenjie Dong Zhenchao Dong Shixuan Du Qitang Fan Xing Fan Qiang Fu Song Gao Jing Guo Weijun Guo Yang He Shimin Hou Ying Jiang Huihui Kong Baojun Li Dengyuan Li Jie Li Qing Li Ruoning Li Shuying Li Yuxuan Lin Mengxi Liu Peinian Liu Yanyan Liu Jingtao Lü Chuanxu Ma Haoyang Pan JinLiang Pan Minghu Pan Xiaohui Qiu Ziyong Shen Qiang Sun Shijing Tan Bing Wang Dong Wang Li Wang Lili Wang Tao Wang Xiang Wang Xingyue Wang Xueyan Wang Yansong Wang Yu Wang Kai Wu Wei Xu Na Xue Linghao Yan Fan Yang Zhiyong Yang Chi Zhang Xue Zhang Yang Zhang Yao Zhang Xiong Zhou Junfa Zhu Yajie Zhang Feixue Gao Yongfeng Wang Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices School of ElectronicsPeking UniversityBeijing 100871China Spin-X Institute School of MicroelectronicsSouth China University of TechnologyGuangzhou 511442China School of Materials and Energy Guangzhou Key Laboratory of Low-Dimensional Materials and Energy Storage DevicesGuangdong University of TechnologyGuangzhou 510006China Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China i-Lab CAS Key Laboratory of Nanophotonic Materials and DevicesSuzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of SciencesBeijing 100190China State Key Laboratory for Organic Electronics and Information Displays&Jiangsu Key Laboratory for Biosensors Institute of Advanced MaterialsJiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing University of Posts and TelecommunicationsNanjing 210023China Institute of Functional Nano and Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and DevicesSoochow UniversitySuzhou 215123China Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China Institute of Physics&University of Chinese Academy of Sciences Beijing 100190China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China College of Chemistry Beijing Normal UniversityBeijing 100875China Beijing National Laboratory for Molecular Sciences(BNLMS) College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China School

Surface with well-defined components and structures possesses unique electronic,magnetic,optical and chemical *** a result,surface chemistry research plays a crucial role in various fields such as catalysis,energy,materials,quantum,and *** science mainly investigates the correspondence between surface property and *** probe microscopy(SPM)techniques are important tools to characterize surface properties because of the capability of atomic-scale imaging,spectroscopy and manipulation at the single-atom *** this review,we summarize recent advances in surface electronic,magnetic and optical properties characterized mainly by SPM-based *** focus on elucidating theπ-magnetism in graphene-based nanostructures,construction of spin qubits on surfaces,topology properties of surface organic structures,STM-based light emission,tip-enhanced Raman spectroscopy and integration of machine learning in SPM studies.

关键词： Surface chemistry Scanning probe microscopy π-Magnetism Spin qubits Tip-enhanced Raman spectroscopy

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Roll angular rate extraction based on modified spline-kernelled chirplet transform

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Defence technology（防务技术） 2022年第5期18卷 876-890页

作者： Hui Zhao Zhong Su Qing Li Fu-chao Liu Ning Liu School of Automation Beijing Institute of TechnologyBeijing100081China Beijing Key Laboratory of High Dynamic Navigation Technology Beijing Information Science and Technology UniversityBeijing100192China

The roll angular rate is much crucial for the guidance and control of the *** the high-speed rotation of the projectile brings severe challenges to the direct measurement of the roll angular ***,the radial magnetometer signal is modulated by the high-speed rotation,thus the roll angular rate can be achieved by extracting the instantaneous frequency of the radial magnetometer *** objective of this study is to find out a precise instantaneous frequency extraction method to obtain an accurate roll angular *** reach this goal,a modified spline-kernelled chirplet transform(MSCT)algorithm is proposed in this *** to the nonlinear frequency modulation characteristics of the radial magnetometer signal,the existing time-frequency analysis methods in literature cannot obtain an excellent energy concentration in the time-frequency plane,thereby leading to a terrible instantaneous frequency extraction ***,the MSCT can overcome the problem of bad energy concentration by replacing the short-time Fourier transform operator with the Chirp Z-transform operator based on the original spline-kernelled chirplet *** introduction of Chirp Z-transform can improve the construction accuracy of the transform *** the construction accuracy of the transform kernel determines the concentration of time-frequency distribution,the MSCT can obtain a more precise instantaneous *** performance of the MSCT was evaluated by a series of numerical simulations,high-speed turntable experiments,and real flight *** evaluation results show that the MSCT has an excellent ability to process the nonlinear frequency modulation signal,and can accurately extract the roll angular rate for the high spinning projectiles.

关键词： high spinning projectile Roll angular rate Time-frequency analysis Spline-kernelled chirplet transform Chirp Z-transform

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Research on the navigation method of large-scale differential tail-control improvised guided munitions based on rotational speed constraints

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Defence technology（防务技术） 2024年第8期38卷 155-170页

作者： Ning Liu Wenjiang Zhao Yao Wang Kai Shen Zhong Su Wenhao Qi Yuedong Xie Beijing Key Laboratory of High Dynamic Navigation Technology Beijing Information Science and Technology UniversityBeijing100192China Hua an Industry Group Co. Ltd.Qiqihar161006China Integrated Navigation and Intelligent Navigation Laboratory Beijing Institute of TechnologyBeijing100081China Beijing Institute of Technology Beijing100081China

In the process of launching guided projectile under the conventional system, it is difficult to effectively obtain the precise navigation parameters of the projectile in the high dynamic environment. Aiming at this problem, this paper describes a new system of guided ammunition based on tail spin reduction. After analyzing the mechanism of the ammunition's tail spin reduction, a navigation method of large scale difference tail control simple guided ammunition based on speed constraint is proposed. In this method,the corresponding navigation constraints can be carried out by combining the rotation speed state of the ammunition itself, and the optimal solution of navigation parameters during the flight of the missile can be obtained by Extended Kalman Filter(EKF). Finally, the performance of the proposed method was verified by the simulation environment, and the hardware-in-the-loop simulation test and flight test were carried out to verify the performance of the method in the real environment. The experimental results show that the proposed method can achieve the optimal estimation of navigation parameters for simple guided ammunition with large-scale difference tail control. Under the conditions of simulation test and hardware-in-loop simulation test, the position and velocity errors calculated by the method in this paper converged. Under the condition of flight test, the spatial average error calculated by the method described in this paper is 6.17 m, and the spatial error of the final landing point is 3.50 *** this method, the accurate acquisition of navigation parameters in the process of projectile launching is effectively realized.

关键词： Guided projectiles Tail spin reduction RPM constraints Combined navigation Extended Kalman filter(EKF)

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Research on Extraction Method of Time-Frequency Feature of Human Motion 31

Research on Extraction Method of Time-Frequency Feature of H...

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第31届中国控制与决策会议

作者： Wang Tianrun Su Zhong Li Chao Liu Ning University of Beijing Information Science & Technology Beijing Key Laboratory of High Dynamic Navigation Technology

ISBN: (纸本)9781728101071;9781728101064

For the problem of motion feature extraction, a method of time-frequency analysis and eigenvalue extraction by fractional Fourier transform is proposed. Collect inertial data in the process of motion by wearing 15 IMU. Analyze and compare its characteristics after the multiorder fractional Fourier transform. The results of the same motion with same order and the different motion with same order and the single motion with different order are compared. Mean value, quartile difference and extreme value difference were extracted after the multiorder fractional Fourier transform to identify and classify the motion.

关键词： Motion recognition IMU Inertial data Feature extraction Fractional Fourier transform

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The guidance control system design of a miniature guided ammunition 7

The guidance control system design of a miniature guided amm...

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2016 IEEE Chinese Guidance, navigation and Control Conference (IEEE CGNCC2016)

作者： AN Xiao-qian FAN Jun-fang Beijing Key Laboratory of High Dynamic Navigation Technology Beijing Information Science & Technology University

ISBN: (纸本)9781467383196

This paper is concentrated on a canard-configured miniature guided ammunition and the pneumatic fluid mechanics simulation calculation results show that the ammunition has good aerodynamic *** the same time,based on the longitudinal linear kinematic equation of the ammunition,the transfer function which is from canard deflection angle to pitch attitude angle and normal acceleration is *** paper designs a two-loop acceleration autopilot,of which the step response characteristics can not only shorten the adjusting time effectively but also better solve the contradiction between rise time and overshoot with a faster convergence *** the two-loop acceleration autopilot can realize fast tracking in the guidance *** research will perform as theoretical basis for the guidance control system integration design of canardconfigured guided ammunition and the analysis of its stability in the future.

关键词： Miniature guided ammunition Aerodynamic characteristics Two-loop acceleration autopilot

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A Unified Coordinate Frame Method for GNSS/MEMS-INS navigation System 31

A Unified Coordinate Frame Method for GNSS/MEMS-INS Navigati...

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第31届中国控制与决策会议

作者： Hailu Wang Zhong Su Ning-Liu Beijing Key Laboratory of high Dynamic Navigation Technology University of Beijing Information Science & Technology

ISBN: (纸本)9781728101071;9781728101064

For GNSS/MEMS-INS integrated navigation system, the traditional geographic coordinates of longitude latitude altitude as navigation parameters involving the floating point operation of angle is improper to be implemented practically. In this paper a unified coordinate transformation algorithm is *** N-coordinate reference frame is served as the reference navigation system. And improved combination algorithms is designed on engineering scenes. Which will reduce the complexity of the combination algorithm, decrease the amount of calculation and reduce the cost of engineering. The method has been tested successfully practically, based on real data and simulation of MEMS sensor and verified the feasibility and navigation accuracy of the algorithm.

关键词： GNSS/MEMS-INS Kalman Filter Uniform Coordinate Frame Integrated Algorithm

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