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A multi-model architecture based on deep learning for aircraft load prediction

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Communications Engineering 2023年第1期2卷 47页

作者： Sun, Chenxi Li, Hongyan Dui, Hongna Hong, Shenda Sun, Yongyue Song, Moxian Cai, Derun Zhang, Baofeng Wang, Qiang Wang, Yongjun Liu, Bo School of Intelligence Science and Technology Peking University Beijing China Key Laboratory of Machine Perception (Ministry of Education) Peking University Beijing China The Aviation Industry Corporation of China Ltd. Chengdu Aircraft Design & amp Research Institute Chengdu China National Institute of Health Data Science Peking University Beijing China Institute of Medical Technology Health Science Center of Peking University Beijing China

Monitoring aircraft structural health with changing loads is critical in aviation and aerospace engineering. However, the load equation needs to be calibrated by ground testing which is costly, and inefficient. Here, we report a general deep learning-based aircraft load model for strain prediction and load model calibration through a two-phase process. First, we identified the causality between key flight parameters and strains. The prediction equation was then integrated into the monitoring process to build a more general load model for load coefficients calibration. This model achieves a 97.16% prediction accuracy and 99.49% goodness-of-fit for a prototype system with 2 million collected flight recording data. This model reduces the effort of ground tests and provides more accurate load prediction with adapted aircraft parameters. © The Author(s) 2023.

关键词： Aerospace engineering Engineering

Communication-Assisted Sensing in 6G Networks

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arXiv 2023年

作者： Dong, Fuwang Liu, Fan Lu, Shihang Xiong, Yifeng Zhang, Qixun Feng, Zhiyong Gao, Feifei School of System Design and Intelligent Manufacturing Southern University of Science and Technology Shenzhen518055 China School of Information and Electronic Engineering Beijing University of Posts and Telecommunications Beijing100876 China Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing100876 China Department of Automation Tsinghua University Beijing100876 China

Exploring the mutual benefit and reciprocity of sensing and communication (S&C) functions is fundamental to realizing deeper integration for integrated sensing and communication (ISAC) systems. This paper investigates a novel communication-assisted sensing (CAS) system within 6G perceptive networks, where the base station actively senses the targets through device-free wireless sensing and simultaneously transmits the estimated information to end-users. In such a CAS system, we first establish an optimal waveform design framework based on the rate-distortion (RD) and source-channel separation (SCT) theorems. After analyzing the relationships between the sensing distortion, coding rate, and communication channel capacity, we propose two distinct waveform design strategies in the scenario of target impulse response estimation. In the separated S&C waveforms scheme, we equivalently transform the original problem into a power allocation problem and develop a low-complexity one-dimensional search algorithm, shedding light on a notable power allocation tradeoff between the S&C waveform. In the dual-functional waveform scheme, we conceive a heuristic mutual information optimization algorithm for the general case, alongside a modified gradient projection algorithm tailored for the scenarios with independent sensing sub-channels. Additionally, we identify the presence of both subspace tradeoff and water-filling tradeoff in this scheme. Finally, we validate the effectiveness of the proposed algorithms through numerical simulations. Copyright © 2023, The Authors. All rights reserved.

关键词： Optimization

Motion Planning for Heterogeneous Unmanned systems under Partial Observation from UAV

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arXiv 2020年

作者： Chen, Ci Wan, Yuanfang Li, Baowei Wang, Chen Xie, Guangming Jiang, Huanyu College of Biosystems Engineering and Food Science Zhejiang University Hangzhou310058 China National Engineering Research Center for Software Engineering Peking University Beijing100871 China State Key Laboratory of Turbulence and Complex Systems Intelligent Biomimetic Design Lab College of Engineering Peking University Beijing100871 China Department of Ocean Science and Engineering Southern University of Science and Technology Shenzhen518055 China Peng Cheng Laboratory Shenzhen518055 China

For heterogeneous unmanned systems composed of unmanned aerial vehicles (UAVs) and unmanned ground vehicles (UGVs), using UAVs serve as eyes to assist UGVs in motion planning is a promising research direction due to the UAVs’ vast view scope. However, due to UAVs flight altitude limitations, it may be impossible to observe the global map, and motion planning in the local map is a POMDP (Partially Observable Markov Decision Process) problem. This paper proposes a motion planning algorithm for heterogeneous unmanned system under partial observation from UAV without reconstruction of global maps, which consists of two parts designed for perception and decision-making, respectively. For the perception part, we propose the Grid Map Generation Network (GMGN), which is used to perceive scenes from UAV’s perspective and classify the pathways and obstacles. For the decision-making part, we propose the Motion Command Generation Network (MCGN). Due to the addition of memory mechanism, MCGN has planning and reasoning abilities under partial observation from UAVs. We evaluate our proposed algorithm by comparing with baseline algorithms. The results show that our method effectively plans the motion of heterogeneous unmanned systems and achieves a relatively high success rate. Copyright © 2020, The Authors. All rights reserved.

关键词： Unmanned aerial vehicles (UAV)

Study of Composition-Modulated Interband Transitions Characteristic and Charge Dynamics Response of High-Throughput FeSe1-xTex Combinatorial Film

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SSRN

SSRN 2024年

作者： Wang, Yueming Wei, Mingyang Li, Yongfu Jin, Kui Lin, Zefeng Zhou, Xiang'an Han, Yating Guan, Xiangyun Lian, Jie School of Information Science and Engineering Shandong Provincial Key Laboratory of Laser Technology and Application Shandong University Qingdao266237 China Center for Optics Research and Engineering Key Laboratory of Laser & Infrared System Ministry of Education Shandong University Qingdao266237 China National Lab for Superconductivity Institute of Physics Chinese Academy of Sciences Beijing100190 China Department of Basic Shandong Urban Construction Vocational College Jinan250100 China

FeSe is regarded as a strong correlation system of simple structure and remarkable tunability in the superconducting transition temperature (Tc). Particularly, the substitution of Se with its isoelectronic Te leads to a dome-shaped Tc evolution, positioning the FeSe1-xTex as an ideal platform for exploring the mechanism of iron-based superconductivity. In this study, we employed high-throughput combinatorial molecular beam epitaxy (CLMBE) to fabricate high-quality FeSe1-xTex film with horizontal gradient. The dielectric spectra of FeSe1-xTex were obtained by ellipsometry spectroscopy (SE). We utilized the standard critical point model and first-principles calculation to identify that the observed interband transitions are predominantly sourced from Fe-3d near the Fermi surface. The pseudogap, extracted from the transitions, shows a bowl-like trend as increased Te, which is negatively correlated with Tc, suggesting a qualitative way to predict Tc in the normal-state. The composition-dependent charge dynamics response, derived from Drude oscillators in SE, indicates that electron-electron interactions might play a more substantial role in FeSe1-xTex superconductivity, combined with the unidirectional electron-phonon coupling result in Raman. The variation of plasma frequency and photoinduced carrier dispersion under composition modulation demonstrates the effect of Te in enhancing system interactions, providing valuable support for the design of superconducting optoelectronic devices. © 2024, The Authors. All rights reserved.

关键词： Iron compounds

Determining impact parameters of heavy-ion collisions at low-intermediate incident energies using deep learning with convolutional neural network

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arXiv 2021年

作者： Zhang, X. Huang, Y. Lin, W. Liu, Xingquan Zheng, H. Wada, R. Bonasera, A. Chen, Z. Chen, L. Han, J. Han, R. Huang, M. Hu, Q. Leng, Q. Ma, C.W. Qu, G. Ren, P. Tian, G. Xu, Z. Yang, Z. Zhang, L. Key Laboratory of Radiation Physics and Technology The Ministry of Education Sichuan University Chengdu610064 China School of Physics and Information Technology Shaanxi Normal University Xi’an710119 China Cyclotron Institute Texas A&M University College StationTX77843 United States Laboratori Nazionali del Sud INFN via Santa Sofia 62 Catania95123 Italy Institute of Modern Physics Chinese Academy of Sciences Lanzhou730000 China College of Physics and Electronics information Inner Mongolia University for Nationalities Tongliao028000 China School of Physics Henan Normal University Xinxiang453007 China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China Chengdu610213 China School of Information Sciences and Engineering Lanzhou University Lanzhou730000 China

A deep learning based method with the convolutional neural network (CNN) algorithm for determining the impact parameters is developed using the constrained molecular dynamics model simulations, focusing on the heavy-ion collisions at the low-intermediate incident energies from several ten to one hundred MeV/nucleon in which the emissions of heavy fragments with the charge numbers larger than 3 become crucial. To make the CNN applicable in the task of the impact parameter determination at the present energy range, specific improvements are made in the input selection, the CNN construction and the CNN training. It is demonstrated from the comparisons of the deep CNN method and the conventional methods with the impact parameter-sensitive observables, that the deep CNN method shows better performance for determining the impact parameters, especially leading to the capability of providing better recognition of the central collision events. With a proper consideration of the experimental filter effect in both training and testing processes to keep consistency with the actual experiments, the good performance of the deep CNN method holds, and shows significantly better in terms of predicting the impact parameters and recognizing the central collision events, compared to that of the conventional methods, demonstrating the superiority of the present deep CNN method. The deep CNN method with the consideration of the filter effect is applied in the deduction of nuclear stopping power. Higher accuracy for the stopping power deduction is achieved benefitting from the better impact parameter determination using the deep CNN method, compared to using the the conventional methods. This result reveals the importance to select a reliable impact parameter determination method in the experimental deduction of the nuclear stopping power as well as other observables. © 2021, CC BY.

关键词： Molecular dynamics

Intelligent Reflecting Surface for MIMO VLC: Joint design of Surface Configuration and Transceiver Signal Processing

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arXiv 2022年

作者： Sun, Shiyuan Yang, Fang Song, Jian Zhang, Rui Department of Electronic Engineering Beijing National Research Center for Information Science and Technology Tsinghua University Beijing100084 China Key Laboratory of Digital TV System of Guangdong Province and Shenzhen City Research Institute of Tsinghua University in Shenzhen Shenzhen518057 China Department of Electrical and Computer Engineering National University of Singapore Singapore117583 Singapore School of Science and Engineering The Chinese University of Hong Kong Shenzhen518172 China

With the capability of reconfiguring the wireless electromagnetic environment, intelligent reflecting surface (IRS) is a new paradigm for designing future wireless communication systems. In this paper, we consider optical IRS for improving the performance of visible light communication (VLC) under a multiple-input and multiple-output (MIMO) setting. Specifically, we focus on the downlink communication of an indoor MIMO VLC system and aim to minimize the mean square error (MSE) of demodulated signals at the receiver. To this end, the MIMO channel gain of the IRS-aided VLC is first derived under the point source assumption, based on which the MSE minimization problem is then formulated subject to the emission power constraints. Next, we propose an alternating optimization algorithm, which decomposes the original problem into three subproblems, to iteratively optimize the IRS configuration, the precoding and detection matrices for minimizing the MSE. Moreover, theoretical analysis on the performance of the proposed algorithm in high and low signal-to-noise ratio (SNR) regimes is provided, revealing that the joint optimization process can be simplified in such special cases, and the algorithm’s convergence property and computational complexity are also discussed. Finally, numerical results show that IRS-aided schemes significantly reduce the MSE as compared to their counterparts without IRS, and the proposed algorithm outperforms other baseline schemes. Copyright © 2022, The Authors. All rights reserved.

关键词： Mean square error

Analysis of the Axial Fan Performance Mounted on a 4.5kW Aviation Motor

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Journal of Physics: Conference Series 2021年第1期1820卷

作者： Bin Liu Zhongjun Yu Jia Fu Zutao Chen National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Wuhan 430033 China

Integrating an axial flow fan with the rotor is a sufficient cooling method for high-speed and high power density motors. Different from the axial fan design work under ideal intake condition, i.e. the intake flow of the fan is axial and uniform, the flow in actual engineering is more complex, which means the flow characteristics of an integrated fan are changed and disturbed. It leads to a performance penalty of the fan, and in some conditions it makes the fan stall, so it is important to get a knowledge of the flow characteristics and the performance of the integrated fan. A certain 4.5kW aviation motor with integrated axial fan is taken as the research object. Firstly, the motor-fan coupling simulation model and ideal axial intake simulation model are established, in which the mass flow rates are same, then calculation is conducted. Secondly, the simulation results are analyzed and compared, focusing on the performance of the axial fan, especially the static pressure rise, and the conclusion is obtained that the static pressure rise in ideal axial intake situation is higher than that in coupling situation. Furthermore, the reasons for the characteristics change are explored, finding that the increase of flow turbulence due to the more complex wind road structure is the main cause for these changes. This paper investigates the flow characteristics and axial fan performance mounted a whole motor, making a contribution to better understand the changes in fan performance under motor-fan coupling situation.

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Structural design of Mos2-Cu Films to Improve Thermal and Tribological Properties of Silicon Nitride Materials

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SSRN

SSRN 2024年

作者： Zhang, Xiaochen Liang, Jiaqi Bai, Xu Wang, Xiaolong Wu, Yuhou Zhang, Ke Zheng, Tongxiang Zhao, Zichen School of mechanical engineering Shenyang Jianzhu University No. 25 Hunnan Middle Road Hunnan District Shenyang110168 China Key Laboratory of Vibration and Control of Aero-Propulsion System Ministry of Education Northeastern University Shenyang110819 China Key Laboratory of Fundamental Science for National Defense of Aeronautical Digital Manufacturing Process of Shenyang Aerospace University Shenyang110135 China School of Mechanical Engineering Shenyang University of Technology No.111 Shenliao West Road Economic & Technological Development Zone Shenyang110870 China National-Local Joint Engineering Laboratory of NC Machining Equipment and Technology of High-Grade Stone Shenyang110168 China

In order to solve the problems of heat dissipation and insufficient wear resistance of silicon nitride materials during dry friction, a novel Ti/TiN/MoS2-Cu lubricated film was deposited on a silicon nitride substrate by magnetron sputtering. The results show that the Ti/TiN structure design promoted MoS2(002) crystal plane growth. Moderate Cu(20W) doping promoted film densification and reduced structural defects, resulting in films with high thermal conductivity and low wear rate. Excessive Cu(40W) doping enabled the films to have high hardness, but due to structural defects and elemental aggregation, the thermal conductivity and abrasion resistance of the films were reduced. The Ti/TiN structure and MoS2-Cu film design provide guidance to improve the thermal and tribological performance of silicon nitride materials. © 2024, The Authors. All rights reserved.

关键词： Friction

MoSi2N4: An emerging 2D electronic material with protected band edge states and dielectric tunable quasiparticle and optical properties

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arXiv 2021年

作者： Wu, Yabei Tang, Zhao Xia, Weiyi Gao, Weiwei Jia, Fanhao Zhang, Yubo Zhu, Wenguang Zhang, Wenqing Zhang, Peihong Department of Physics Shenzhen Institute for Quantum Science & Engineering Southern University of Science and Technology Guangdong Shenzhen518055 China Guangdong Provincial Key Lab for Computational Science and Materials Design Shenzhen Municipal Key Lab for Advanced Quantum Materials and Devices Southern University of Science and Technology Guangdong Shenzhen518055 China Icqd Hefei National Laboratory for Physical Science at the Microscale Key Laboratory of Strongly-Coupled Quantum Matter Physics Chinese Academy of Sciences Department of Physics Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China Anhui Hefei230026 China Department of Physics University at Buffalo State University of New York BuffaloNY14260 United States Department of Physics Dalian University of Technology Liaoning Dalian116024 China International Centre for Quantum and Molecular Structures Materials Genome Institute Department of Physics Shanghai University 99 Shangda Road Shanghai200444 China

As it is the case for all low-dimensional materials, the low energy electronic structure of two-dimensional (2D) materials are inherently prone to environmental perturbations. While there are applications (e.g., sensors) that exploit this property, the fact that the band-edge states of 2D materials are susceptible to often unpredictable environmental coupling effects may pose significant challenges to their practical applications in electronic or optoelectronic devices. A 2D material couples with its environment through two mechanisms: local chemical coupling arising from the overlap and hybridization of wave functions, and nonlocal dielectric screening effects that renormalize the Coulomb interaction in the system. The local chemical coupling, which may arise from the (often unintentional) surface adsorption or interfacial chemical coupling, is difficult to predict or control experimentally. Nonlocal dielectric screening effects, on the other hand, can be tuned by choosing the substrates or layer thickness in a controllable manner. Therefore, a compelling 2D electronic material should offer band edge states that are robust against local chemical coupling effects. Here we demonstrate that the recently synthesized MoSi2N4is an ideal 2D semiconductor with robust band edge states protected from capricious environmental chemical coupling effects. We have carried out thorough density functional theory (DFT) and many-body perturbation theory (MBPT) calculations to illustrate how the band edge states of MoSi2N4are essentially shielded from direct chemical coupling to its environment, and, at the same time, the quasiparticle and optical properties of MoSi2N4can be modulated through the nonlocal dielectric screening effects. This unique property, together with the moderate band gap and the thermodynamic and mechanical stability of this material, may pave the way for a range of applications in areas including energy, 2D electronics, and optoelectronics. Copyright © 2021, The

关键词： Mechanical stability