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arXiv 2024年

作者： Gao, Weihua Niu, Wenlong Lu, Wenlong Wang, Pengcheng Qi, Zhaoyuan Peng, Xiaodong Yang, Zhen The Key Laboratory of Electronics and Information Technology for Space Systems National Space Science Center Chinese Academy of Sciences Beijing100190 China The School of Computer Science and Technology University of Chinese Academy of Sciences Beijing100049 China

The detection and tracking of small targets in passive optical remote sensing (PORS) has broad applications. However, most of the previously proposed methods seldom utilize the abundant temporal features formed by target motion, resulting in poor detection and tracking performance for low signal-to-clutter ratio (SCR) targets. In this article, we analyze the difficulty based on spatial features and the feasibility based on temporal features of realizing effective detection. According to this analysis, we use a multi-frame as a detection unit and propose a detection method based on temporal energy selective scaling (TESS). Specifically, we investigated the composition of intensity temporal profiles (ITPs) formed by pixels on a multi-frame detection unit. For the target-present pixel, the target passing through the pixel will bring a weak transient disturbance on the ITP and introduce a change in the statistical properties of ITP. We use a well-designed function to amplify the transient disturbance, suppress the background and noise components, and output the trajectory of the target on the multi-frame detection unit. Subsequently, to solve the contradiction between the detection rate and the false alarm rate brought by the traditional threshold segmentation, we associate the temporal and spatial features of the output trajectory and propose a trajectory extraction method based on the 3D Hough transform. Finally, we model the trajectory of the target and propose a trajectory-based multi-target tracking method. Compared with the various state-of-the-art detection and tracking methods, experiments in multiple scenarios prove the superiority of our proposed methods. Copyright © 2024, The Authors. All rights reserved.

关键词： Optical remote sensing

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Operational Effectiveness Evaluation of Reconnaissance Satellite System based on System Dynamics Model 2

Operational Effectiveness Evaluation of Reconnaissance Satel...

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2nd IEEE International Conference on Information technology, Big Data and Artificial Intelligence, ICIBA 2021

作者： Han, Chi Xiong, Wei Liu, Wenwen Yu, Xiaolan Jian, Ping Aerospace Information Institute Space Engineering University Beijing China Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China

ISBN: (纸本)9781665428767

In order to study changes in the effectiveness of reconnaissance satellite system (RSS) in supporting maritime operations, based on the key factors of dynamic confrontation system of the offensive and defensive parties, the feedback relationships between variables are analyzed. According to the feedback relationship, a system dynamics (SD) model based on Lanchester equation was established and simulated on the VENSIM platform to compare and analyze operational effectiveness of different RSS allocation schemes. simulation analysis shows that RSS can increase the rate of detection and acquisition of information and accelerate the loss of the enemy. At the same time, when the sensor parameters are similar, increasing the number of weapons can significantly reduce the loss, which provides a certain theoretical support for decision-making analysis in combat. © 2021 IEEE.

关键词： Feedback

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MTL-JER: Meta-Transfer Learning for Low-Resource Joint Entity and Relation Extraction

MTL-JER: Meta-Transfer Learning for Low-Resource Joint Entit...

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Neural Networks, Information and Communication Engineering (NNICE), International Conference on

作者： Da Peng Zhongmin Pei Delin Mo Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China Institute of War Studies Academy of Military Sciences

Joint entity and relation extraction has achieved impressive advances in NLP, such as document understanding and knowledge graph construction. The typical methods for entity and relation extraction typically break down the joint task into several smaller components or stages for ease of implementation, but this leads to a loss of the interconnected knowledge in the triple. Hence, we propose to model the triple in one module jointly. Furthermore, the labeling of a joint entity and relation extraction tasks is costly and domain-specific; therefore, it is important to improve its performance on low-resource data and domain adaption. To address this issue, we suggest using two sources that are rich in information, namely pre-trained models on large data and multi-domain text corpora. Pretraining allows us to provide the model with the fundamental ability to perform joint entity and relationship extraction. Second, through meta-learning on multi-domain text, we can improve the model's generalization capabilities, enabling it to perform well even with limited data. We present MTL-JER, a Meta-Transfer Learning method for Joint Entity and Relation Extraction in low-resource settings in this paper. Using exhaustive experiments on five datasets, we prove that our model obtains optimal results.

关键词： Adaptation models Training data Knowledge graphs Artificial neural networks Data models Data mining Labeling

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Effectiveness Evaluation of Reconnaissance Satellite System based on Analytic Hierarchy Process and Cloud Model 5

Effectiveness Evaluation of Reconnaissance Satellite System ...

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5th IEEE Information technology, Networking, Electronic and Automation Control Conference, ITNEC 2021

作者： Han, Chi Xiong, Wei Xiong, Minghui Liu, Zhen Liu, Wenwen Yu, Xiaolan Jian, Ping Space Engineering University Aerospace Information Institute Beijing China Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China

ISBN: (纸本)9781665415989

Considering the complexity of effectiveness evaluation index of reconnaissance satellite system (RSS), the cloud model theory and AHP method are combined. A fuzzy evaluation method of combat effectiveness based on cloud model is proposed. A multi-layer evaluation index system is constructed through the AHP method, and the weight of each level index is calculated. Combining the multi-dimensional cloud model with the AHP method, a quantitative fuzzy evaluation method for qualitative indicators and quantitative data is designed, and the qualitative evaluation results are obtained. The experimental results show that the proposed evaluation method can effectively realize the fuzzy quantitative evaluation under the complex evaluation index system with good performance in terms of calculation accuracy and fuzziness. © 2021 IEEE.

关键词： Analytic hierarchy process

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Image Desaturation for SDO/AIA Using Mixed Convolution Network

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Research in Astronomy and Astrophysics 2022年第6期22卷 91-100页

作者： Xuexin Yu Long Xu Zhixiang Ren Dong Zhao Wenqing Sun National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Peng Cheng National Laboratory Shenzhen 518000China National Space Science Center Chinese Academy of SciencesBeijing 100190China State Key Laboratory of Virtual Reality Technology and Systems School of Computer Science and EngineeringBeihang UniversityBeijing 100190China

The Atmospheric Imaging Assembly(AIA)onboard the Solar Dynamics Observatory(SDO)provides full-disk solar images with high temporal cadence and spatial resolution over seven extreme ultraviolet(EUV)wave ***,as violent solar flares happen,images captured in EUV wave bands may have saturation in active regions,resulting in signal *** this paper,we propose a deep learning model to restore the lost signal in saturated regions by referring to both unsaturated/normal regions within a solar image and statistical probability model of massive normal solar *** proposed model,namely mixed convolution network(MCNet),is established over conditional generative adversarial network(GAN)and the combination of partial convolution(PC)and validness migratable convolution(VMC).These two convolutions were originally proposed for image *** addition,they are implemented only on unsaturated/valid pixels,followed by certain compensation to compensate the deviation of PC/VMC relative to normal *** results demonstrate that the proposed MCNet achieves favorable desaturated results for solar images and outperforms the state-of-the-art methods both quantitatively and qualitatively.

关键词： Sun:activity Sun atmosphere-Sun chromosphere

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LEO Satellite Network Traffic Forecasting based on ARIMA-BPNN Model

LEO Satellite Network Traffic Forecasting based on ARIMA-BPN...

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Electronic Information Engineering and Computer Communication (EIECC), International Conference on

作者： Chi Han Wei Xiong Ronghuan Yu Jingyu Fu Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China Jiuquan Satellite Launch Center Jiuquan China

Satellite network traffic forecasting provides key information for routing and resource allocation, which is important for the efficient operation of satellite network. However, due to the self-similarity and long-range dependence (LRD) of satellite network traffic, traditional linear or non-linear network traffic forecasting models cannot achieve sufficient forecasting accuracy. A combined model of satellite network traffic forecasting based on BPNN and ARIMA is proposed. BPNN is adopted to forecast the residuals. EMD-ARIMA and BPNN forecasting results are combined to achieve satellite network traffic forecasting. Experimental results on the satellite network traffic data generated by the ON/OFF model show that forecast accuracy of the proposed method is better than traditional model, which verifies the effectiveness of the proposed satellite network traffic forecast model.

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Relationship of mode transitions and standing waves in helicon plasmas

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Plasma science and technology 2022年第5期24卷 80-86页

作者： Mingyang WU Chijie XIAO Xiaogang WANG Yue LIU Min XU Chang TAN Tianchao XU Xiuming YU Renchuan HE Andong XU State Key Laboratory of Nuclear Physics and Technology School of PhysicsFusion Simulation CenterPeking UniversityBeijing 100871People’s Republic of China Department of Physics Institute of Space Environment and Matter ScienceHarbin Institute of TechnologyHarbin 150001People’s Republic of China Key Laboratory of Materials Modiﬁcation by Laser Ion and Electron Beams(Ministry of Education)School of PhysicsDalian University of TechnologyDalian 116024People’s Republic of China Center for Fusion Science of Southwestern Institute of Physics Chengdu 610041People’s Republic of China Shaanxi Key Laboratory of Plasma Physics and Applied Technology Xi’an 710100People’s Republic of China Xi’an Aerospace Propulsion Institute Xi’an 710100People’s Republic of China

Helicon wave plasma sources have the well-known advantages of high efficiency and high plasma density, with broad applications in many areas. The crucial mechanism lies with mode transitions, which has been an outstanding issue for years. We have built a fluid simulation model and further developed the Peking University Helicon Discharge code. The mode transitions, also known as density jumps, of a single-loop antenna discharge are reproduced in simulations for the first time. It is found that large-amplitude standing helicon waves(SHWs) are responsible for the mode transitions, similar to those of a resonant cavity for laser *** paper intends to give a complete and quantitative SHW resonance theory to explain the relationship of the mode transitions and the SHWs. The SHW resonance theory reasonably explains several key questions in helicon plasmas, such as mode transition and efficient power absorption, and helps to improve future plasma generation methods.

关键词： helicon plasma mode transition standing wave resonance

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Discovering API Directives from API Specifications with Text Classification

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Journal of Computer science & technology 2021年第4期36卷 922-943页

作者： Jing-Xuan Zhang Chuan-Qi Tao Zhi-Qiu Huang Xin Chen College of Compute Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Safety-Critical Software(Nanjing University of Aeronautics and Astronautics) Ministry of Industry and Information TechnologyNanjing 210016China Key Laboratory of Complex Systems Modeling and Simulation(Hangzhou Dianzi University) Ministry of Education Hangzhou 310018China School of Computer Science and Technology Hangzhou Dianzi UniversityHangzhou 310018China

Application programming interface(API)libraries are extensively used by *** correctly program with APIs and avoid bugs,developers shall pay attention to API directives,which illustrate the constraints of ***,API directives usually have diverse morphologies,making it time-consuming and error-prone for developers to discover all the relevant API *** this paper,we propose an approach leveraging text classification to discover API directives from API ***,given a set of training sentences in API specifications,our approach first characterizes each sentence by three groups of ***,to deal with the unequal distribution between API directives and non-directives,our approach employs an under-sampling strategy to split the imbalanced training set into several subsets and trains several *** a new sentence in an API specification,our approach synthesizes the trained classifiers to predict whether it is an API *** have evaluated our approach over a publicly available annotated API directive *** experimental results reveal that our approach achieves an F-measure value of up to 82.08%.In addition,our approach statistically outperforms the state-of-the-art approach by up to 29.67%in terms of F-measure.

关键词： Application programming interface(API)directive API specification imbalanced learning text classification

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Gearman Based Distributed Computation of space Target Photometry

Gearman Based Distributed Computation of Space Target Photom...

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Informatics, Networking and Computing (ICINC), International Conference on

作者： Miao Tian Peixuan Li Wenbo Song Jieping Xu Science and Technology on Complex Electronic System Simulation laboratory Space Engineering University Beijing China

Photometry is an important optical characteristic of space targets. Due to the huge computational volume of the photometry of the full-angle of a space target, the computation time is long and is difficult to meet the realistic demand. In this study, a Gearman based distributed parallel computation framework is constructed to automatically decompose and distribute the photometry computation tasks, automatically balance the computational load, and compose the computational results. This method divides the target photometry calculation into four independent variables, conducts distributed parallel calculation respectively, and finally integrates the calculation results into single target photometry information. The distributed parallel photometry computation method based on Gearman framework is important for fast computation of full-angle photometry data of space targets and assisting space target situational awareness tasks.

关键词： Integrated optics Distributed databases Optical variables control Task analysis Informatics Photometry

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Research on Multi-Satellite Mission Planning Based on Improved Genetic Algorithm

Research on Multi-Satellite Mission Planning Based on Improv...

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Computer science and Management technology (ICCSMT), International Conference on

作者： Yang Yang Desheng Liu Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China

For the multi-satellite mission planning problem, a multi-satellite mission planning model is constructed by considering the constraints of satellite’s visibility window to the target, attitude transition, storage and energy consumption, and an improved genetic algorithm is proposed to solve the model. The algorithm adopts the real number coding method to improve the solution efficiency, introduces the adaptive mechanism and the elite retention strategy, which improves the problems that the genetic algorithm is easy to fall into local optimum and converge early. The effectiveness of the improved genetic algorithm for solving multi-star mission planning is verified through simulation case analysis, and it is compared and analyzed with the standard genetic algorithm. The results show that the well genetic algorithm can achieve faster convergence and better planning results, and has better adaptability to large-scale mission planning problems.

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