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Multi-AUV Cooperative Underwater Multi-Target Tracking Based on Dynamic-Switching-enabled Multi-Agent Reinforcement Learning

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arXiv 2024年

作者： Wang, Shengbo Lin, Chuan Han, Guangjie Zhu, Shengchao Li, Zhixian Wang, Zhenyu Ma, Yunpeng Software College Northeastern University Shenyang China Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Ministry of Education China Department of Internet of Things Engineering Hohai University Changzhou213022 China Jiangsu Key Laboratory of Power Transmission and Distribution Equipment Technology Hohai University China

In recent years, autonomous underwater vehicle (AUV) swarms are gradually becoming popular and have been widely promoted in ocean exploration or underwater tracking, etc. In this paper, we propose a multi-AUV cooperative underwater multi-target tracking algorithm especially when the real underwater factors are taken into account. We first give normally modelling approach for the underwater sonar-based detection and the ocean current interference on the target tracking process. Then, based on software-defined networking (SDN), we regard the AUV swarm as a underwater ad-hoc network and propose a hierarchical software-defined multi-AUV reinforcement learning (HSARL) architecture. Based on the proposed HSARL architecture, we propose the"Dynamic-Switching" mechanism, it includes"Dynamic-Switching Attention" and"Dynamic-Switching Resampling" mechanisms which accelerate the HSARL algorithm’s convergence speed and effectively prevents it from getting stuck in a local optimum state. Additionally, we introduce the reward reshaping mechanism for further accelerating the convergence speed of the proposed HSARL algorithm in early phase. Finally, based on a proposed AUV classification method, we propose a cooperative tracking algorithm called Dynamic-Switching-Based MARL (DSBM)driven tracking algorithm. Evaluation results demonstrate that our proposed DSBM tracking algorithm can perform precise underwater multi-target tracking, comparing with many of recent research products in terms of various important metrics. Copyright © 2024, The Authors. All rights reserved.

关键词： Reinforcement learning

Al_xCoCrCuFeNi (X = 0, 0.8) high entropy alloys fabricated by laser powder bed fusion

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Heat Treatment and Surface Engineering 2024年第1期6卷

作者： Feng, Zhengjie Gao, Jingbo Zhang, Deliang School of Materials Science and Engineering Northeastern University Shenyang China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang China Key Laboratory of Data Analytics and Optimization for Smart Industry (Ministry of Education) Northeastern University Shenyang China

The AlxCoCrCuFeNi (x = 0, 0.8) high entropy alloys (HEAs) were prepared by laser powder bed fusion (LPBF), and the effects of volumetric energy density (VED) and heat treatment on microstructures and mechanical proper... 详细信息

The Al_xCoCrCuFeNi (x = 0, 0.8) high entropy alloys (HEAs) were prepared by laser powder bed fusion (LPBF), and the effects of volumetric energy density (VED) and heat treatment on microstructures and mechanical properties of HEAs were investigated. The results show that the CoCrCuFeNi HEA has a single FCC phase structure and exhibits good ductility. Its yield strength is relatively low, being 520 MPa. After the alloy composition was adjusted from CoCrCuFeNi to Al_0.8CoCrCuFeNi, the HEA changed from FCC single-phase to FCC + BCC dual-phase structure and the hardness and compressive properties were significantly improved. Among them, the Al_0.8CoCrCuFeNi HEA prepared with the VED of 167 J/mm³ has the best mechanical properties, with a compressive yield strength of 652 MPa and good plasticity. After annealing at 600°C and 900°C for 1 h, the mechanical properties of HEAs are significantly improved. In particular, the microhardness and compressive yield strength of the Al_0.8CoCrCuFeNi HEA annealed at 600°C for 1 h are 378 HV and 810 MPa, respectively. The coordinated deformation between FCC and BCC domains, back stress strengthening, solid solution strengthening and precipitation strengthening after heat treatment make the Al_0.8CoCrCuFeNi HEA achieve a balance of high strength and good ductility. © 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

关键词： heat treatment high entropy alloys Laser powder bed fusion mechanical properties microstructures

Microstructure and mechanical properties of a recycled aluminum alloy fabricated by consolidation of small pieces

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Heat Treatment and Surface Engineering 2024年第1期6卷

作者： Liu, Feifei Zhang, Deliang School of Materials Science and Engineering Northeastern University Shenyang China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang China Key Laboratory of Data Analytics and Optimization for Smart Industry (Ministry of Education) Northeastern University Shenyang China

The microstructure and mechanical properties of recycled AA6063 aluminum alloy rods fabricated by hot extrusion of forging compacts formed by upsetting compacts of small AA6063 aluminum alloy pieces with different Fe contents before and after T6 heat treatment were studied. In the as-extruded state and with the higher extrusion ratio of 25:1, the microstructure consists of fully recrystallized grains, but the high iron content regions exhibit clearly finer equiaxed grains due to the stronger grain boundary pinning and nucleation effects of a higher number density of Fe-rich phase particles. Increasing the extrusion ratio increases both the strength and ductility of the as-extruded material. The reason is that increasing extrusion ratio enhances the bonding strength of the prior boundaries between the strips formed by deformation of the small pieces. In the T6 heat-treated state, increasing the extrusion ratio from 9:1 to 25:1 clearly increases the fraction of fine and equiaxed grains. The enhancement of the bonding strength and the refinement of the microstructure with the increase of extrusion ratio cause the yield strength and ultimate tensile strength to increase from 174 and 221 MPa to 213 and 237 MPa, respectively, and the elongation to fracture to decrease from 22.1 to 15.4%. Solid-state recycled samples all exhibit a ductile fracture behavior despite formation of microcracks at the prior boundaries. © 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

关键词： Aluminum alloy hot extrusion mechanical properties microstructure solid state recycling

Annihilating the Formation of Silicon Carbide:Molten Salt Electrolysis of Carbon-Silica Composite to Prepare the Carbon-Silicon Hybrid for Lithium-lon Battery Anode

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Energy & Environmental Materials 2020年第2期3卷 166-176页

作者： Xianbo Zhou Hongwei Xie Xiao He Zhuqing Zhao Qiang Ma Muya Cai Huayi Yin Key Laboratory for Ecological Metallurgy of Multimetallic Mineral of Ministry of Education School of metallurgyNortheastern University110819Shenyang China Key Laboratory of Data Analytics and Optimization for Smart Industry(Northeastern University) Ministry of Education110819Shenyang China

Silicon(Si)and carbon(C)composites hold the promise for replacing the commercial graphite anode,thus increasing the energy density of lithium-ion batteries(LIBs).To mitigate the formation of SiC,this paper reports a molten salt electrolysis approach to prepare C-Si composite by the electrolysis of C-SiO2 *** the conventional way of making a C coating on Si,C-SiO2 composites were prepared by pyrolyzing the low-cost sucrose and *** electrochemical deoxidation of the C-SiO2 composites not only produces nanostructured Si inside the C matrix but also introduces voids between the C and Si owing to the volume shrinkage from converting SiO2 to *** importantly,the use of Mg ion-containing molten salts precludes the generation of SiC,and the electrolytic Si@C composite anode delivers a capacity of about 1500 mAh g-1 after 100 cycles at a current density of 500 mA ***,the Si@C‖LiNi0.6Co0.2Mn0.2O2 full cell delivers a high energy density of 608 Wh ***,the molten salt approach provides a one-step electrochemical way to convert oxides@C to metals@C functional materials.

关键词： anode material carbon lithium-ion batteries molten salt electrolysis silicon

Exergy transfer characteristics and structural parameters optimization in blast furnace slag heat recovery device 2

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Exergy transfer characteristics and structural parameters op...

2023 2nd International Conference on Energy and Power Engineering, EPE 2023

作者： Tao, Sheng Kai Yu, Qing Bo Yu, Zhen Yu Liu, Hai Wei Yang, Chen School of Metallurgy Northeastern University No. 11 Wenhua Road Heping District Lane 3 Liaoning Shenyang110819 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization No. 11 Wenhua Road Heping District Lane 3 Liaoning Shenyang110819 China Key Laboratory of Data Analytic and Optimization for Smart Industry Northeastern University No. 11 Wenhua Road Heping District Lane 3 Liaoning Shenyang110819 China

Thermodynamic analysis was employed to evaluate an MBHE (moving bed heat exchanger) for heat recovery from BFS (blast furnace slag). The study conducted experimental investigations to assess the influence of several factors on heat transfer, exergy transfer, and exergy destruction, including the granular side Peclet number, waterside Reynolds number, arrangement, tube spacing, and tube shape. Structural parameters of the MBHE were optimized based on the heat transfer enhancement number, resulting in the determination of the optimal parameters: staggered arrangement, Dh/D=2, Dv/D=3, and elliptical tubes. © Published under licence by IOP Publishing Ltd.

关键词： Slags

A general Dabrowski-Sitarz-Zalecki type theorems for manifold with boundary

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arXiv 2023年

作者： Wu, Tong Wang, Yong Department of Mathematics Northeastern University Shenyang110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Ministry of Education China School of Mathematics and Statistics Northeast Normal University Changchun130024 China

In [17], we obtained the spectral Einstein functional associated with the Dirac operator for n-dimensional manifolds without boundary. In this paper, we give the proof of general Dabrowski-Sitarz-Zalecki type theorems for the spectral Einstein functional associated with the Dirac operator on even and odd dimensional manifolds with boundary. Copyright © 2023, The Authors. All rights reserved.

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Standard siren cosmology in the era of the 2.5-generation ground-based gravitational wave detectors: bright and dark sirens of LIGO Voyager and NEMO

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arXiv 2023年

作者： Jin, Shang-Jie Zhu, Rui-Qi Song, Ji-Yu Han, Tao Zhang, Jing-Fei Zhang, Xin College of Sciences Northeastern University Shenyang110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education Northeastern University Shenyang110819 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China

The 2.5-generation (2.5G) ground-based gravitational wave (GW) detectors LIGO Voyager and NEMO are expected to be operational in the late 2020s and early 2030s. In this work, we explore the potential of GW standard sirens observed by the 2.5G GW detectors in measuring cosmological parameters, especially for the Hubble constant. Using GWs to measure cosmological parameters is inherently challenging, especially for 2.5G detectors, given their limited capability, which results in weaker constraints on cosmological parameters from the detected standard sirens. However, the measurement of the Hubble constant using standard siren observations from Voyager and NEMO is still promising. For example, using bright sirens from Voyager and NEMO can measure the Hubble constant with a precision of about 2% and 6% respectively, and using the Voyager-NEMO network can improve the precision to about 1.6%. Moreover, bright sirens can be used to break the degeneracy of cosmological parameters generated by CMB data, and to a certain extent, 2.5G detectors can also play a role in this aspect. Observations of dark sirens by 2.5G detectors can achieve relatively good results in measuring the Hubble constant, with a precision of within 2%, and if combining observations of bright and dark sirens, the precision of the Hubble constant measurement can reach about 1.4%. Finally, we also discussed the impact of the uncertainty in the binary neutron star merger rate on the estimation of cosmological parameters. We conclude that the magnificent prospect for solving the Hubble tension is worth expecting in the era of the 2.5G ground-based GW detectors. Copyright © 2023, The Authors. All rights reserved.

关键词： Cosmology

Differential Evolution With Multivariate Gaussian Sampling For Sensor Arrangement

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Differential Evolution With Multivariate Gaussian Sampling F...

China Semiconductor Technology International Conference (CSTIC)

作者： Kuiling Du Gang Tang National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang China Key Laboratory of Data Analytics and Optimization for Smart Industry (Northeastern University) Ministry of Education Shenyang China China Construction Fifth Engineering Bureau Ltd Changsha Hunan China

Sensor arrangement problems with the unknown number of sensors and obstacles in an area to be covered by sensors, which are complicated for common evolutionary algorithms to search for the global optimum. This paper presented a new evolutionary algorithm to solve the problem, which utilized hybrid mutation and a specific crossover strategy. Sampling the best individual of the population using the multivariate Gaussian distribution during the mutation process, and the individuals generated by multivariate Gaussian sampling would skip the crossover to selection. It has been proved that the new algorithm has better solution quality and faster convergent speed than classic differential evolution (DE).

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A comprehensive forecast for cosmological parameter estimation using joint observations of gravitational waves and short γ-ray bursts

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arXiv 2023年

作者： Han, Tao Jin, Shang-Jie Zhang, Jing-Fei Zhang, Xin College of Sciences Northeastern University Shenyang110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education Northeastern University Shenyang110819 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China

In the third-generation (3G) gravitational-wave (GW) detector era, the multi-messenger GW observation for binary neutron star (BNS) merger events can exert great impacts on exploring the cosmic expansion history. In this work, we comprehensively explore the potential of 3G GW standard siren observations in cosmological parameter estimations by considering the 3G GW detectors and the future short γ-ray burst (GRB) detector THESEUS-like telescope joint observations. Based on the 10-year observation of different detection strategies, we predict that the numbers of detectable GW-GRB events are 334-674 with the redshifts z ◦. For the cosmological analysis, we consider the ΛCDM, wCDM, w0waCDM models, and interacting dark energy (IDE) models. We find that GW can tightly constrain the Hubble constant with precisions of 0.345%-0.065%, but perform not well in constraining other cosmological parameters. Fortunately, GW could effectively break the cosmological parameter degeneracies generated by the mainstream EM observations, CMB+BAO+SN (CBS). When combining the mock GW data with the CBS data, CBS+GW can tightly constrain the equation of state of dark energy w with a precision of 1.26%, close to the standard of precision cosmology. Meanwhile, the addition of GW to CBS could improve constraints on cosmological parameters by 34.2%-94.9%. In conclusion, GW standard siren observations from 3G GW detectors could play a crucial role in helping solve the Hubble tension and probe the fundamental nature of dark energy. Copyright © 2023, The Authors. All rights reserved.

关键词： Gravity waves