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Data-Driven Modeling Approach for Mistuned Cyclic Structures

AIAA JOURNAL 2021年第7期59卷 2684-2696页

作者： Kelly, Sean T. Lupini, Andrea Epureanu, Bogdan, I Univ Michigan Dept Mech Engn Ann Arbor MI 48109 USA

A data-driven approach to predict dynamic responses of mistuned cyclic dynamic structures is presented. Nominally cyclic structures such as turbomachinery bladed disks, or blisks, contain deviations from perfect symmetry, called mistuning, which can significantly increase the forced response of the structure subject to periodic excitations. The ability to accurately model the response is crucial for understanding a structure's dynamics during operation, and thus many reduced-order models have been developed. Data-driven approaches, however, are largely unexplored for predicting physical responses of cyclic structures, and are desirable due to their ability to leverage both computational and experimental data. In this paper, two feed-forward neural networks (FFNNs) are trained using physical responses and parameters from an individual sector of the cyclic structure. The desired physical responses of all sectors are predicted via a cyclic coupling procedure. By only using sector-level data, the number of simulations and/or experiments required to generate training data is substantially reduced, and the approach is not restricted to a specific projection basis unlike previous physics-based methods. A lumped mass model (LMM) of a blisk with stiffness mistuning is used to generate computational surrogate data for training and validation. Both FFNNs achieve high prediction accuracy on both training data and unseen test data. For a test case with an unseen mistuning pattern, this approach shows strong agreement with known actual responses. For this test case, prediction errors in the LMM blade tip amplitudes across all sectors are less than 2%, and the amplification factor error is less than 0.2%.

关键词： Convolutional Neural Network Structural Dynamics Turbomachinery Bladed Disks Stiffness Matrices optimization algorithm Frequency Domain Boundary Value Problems Structural Health Monitoring Graphics Processing Unit Monte Carlo Simulation

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A Unified Electrothermal Behavior Modeling Method for Both SiC MOSFET and GaN HEMT

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IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS 2021年第10期68卷 9366-9375页

作者： Long, Xiao Jun, Zhao Zhang, Botao Chen, Dongdong Liang, Wu Minnan Univ Sci & Technol Sch Elect & Elect Engn Quanzhou 362700 Peoples R China Northeastern Univ State Key Lab Synthet Automat Proc Ind Shenyang 110819 Peoples R China Zhejiang Univ Coll Elect Engn Hangzhou 310027 Peoples R China Wuhan Univ Sci & Technol Sch Comp Sci & Technol Wuhan 430065 Peoples R China

This article has presented a unified electrothermal behavior modeling method for both silicon carbide (SiC) metal oxide semiconductor field effect transistor (mosfet) and gallium nitride (GaN) high electron mobility transistor (HEMT). The electrothemal behavior of these two kind of devices in both the first and the third quadrant is accurately modeled with serval compact equations. A modeling data and optimization algorithm-based parameter extraction method have been proposed to replace the previous time consuming and labor intensive one. The proposed parameter fitting algorithm is a genetic algorithm and Levenberg-Marquardt combined optimization algorithm possessing the advantages of global optimization and fast convergence speed, and modeling data can come from both datasheets and measurement. The correctness and accuracy of the proposed modeling method has been verified by simulation and experiment result. Meanwhile, it has been proved that the proposed modeling method is applicable to several commercially available SiC mosfets and GaN HEMTs.

关键词： Mathematical model Semiconductor device modeling MOSFET Silicon carbide Gallium nitride HEMTs Logic gates Electrothermal model gallium nitride (GaN) high electron mobility transistor (HEMT) optimization algorithm parameter extraction silicon carbide metal oxide semiconductor field effect transistor (MOSFET)

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The development trend of China's natural gas consumption: A forecasting viewpoint based on grey forecasting model

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ENERGY REPORTS 2021年 7卷 4308-4324页

作者： Zhang, Jun Qin, Yanping Duo, Huaqiong Inner Mongolia Agr Univ Coll Sci Hohhot 010018 Peoples R China Inner Mongolia Agr Univ Coll Mat Sci & Art Design Hohhot 010018 Peoples R China

In the context of global emission reduction, as a type of clean and eco-friendly energy, natural gas has attracted wide attention. Accurate prediction of natural gas consumption can provide reference for relevant departments to formulate the corresponding development plans and strategies. At present, there are many forecasting tools for processing and analysing natural gas consumption, but most of them have the disadvantages of complex modelling or low precision. In order to solve this problem, inspired by the polynomial regression prediction model and the discrete grey prediction model, a novel polynomial discrete grey prediction model with fractional order accumulation (abbreviated as FPDGM(1,1) model) is established in this paper. In order to find the optimal parameters of the FPDGM(1,1) model, three most popular intelligent algorithms are used to solve the parameters of the model, and then the optimal parameters from the three intelligent algorithms are selected in this paper. In addition, the advantages of the FPDGM(1,1) model over other four forecasting models are confirmed through two parts in this paper. First, the natural gas consumptions of four municipalities in China are used as cases to verify the effectiveness of the FPDGM(1,1) model in this paper. Subsequently, the FPDGM(1,1) model and several kinds of frequently used forecasting models are applied to analyse and predict China's natural gas consumption, and the FPDGM(1,1) model is used to predict China's natural gas consumption in the next 5 years. The results of these two parts indicate that the FPDGM(1,1) model shows the best predictive performance in all cases. Lastly, based on the predicted results of the FPDGM(1,1) model, some reasonable suggestions are put forward for China's natural gas development plan. (C) 2021 Published by Elsevier Ltd.

关键词： Natural gas consumption Polynomial regression prediction model Discrete grey prediction model optimization algorithm

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Comparison of Electrified Aircraft Propulsion Drive Systems with Different Electric Motor Topologies

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JOURNAL OF PROPULSION AND POWER 2021年第5期37卷 733-747页

作者： Sirimanna, Samith Thanatheepan, Balachandran Lee, Dongsu Agrawal, Shivang Yu, Yangxue Wang, Yuyao Anderson, Aaron Banerjee, Arijit Haran, Kiruba Univ Illinois Dept Elect & Comp Engn Urbana IL 61801 USA Univ Illinois Urbana IL 61801 USA Hitet LLC Champaign IL USA

Y Electric aircraft propulsion is a growing research area that looks into achieving propulsion through fully electric or hybrid electric systems while achieving low CO2 emissions. The system-level benefit gained by different electric and hybrid-electric propulsion schemes depends heavily on the performance of system-level components in the electric drive-train, including the electric motor, gear box, motor drive, protection systems, as well as the thermal management system. When comparing motor topologies, it is important to understand performance measures such as efficiency and specific power on a drive system level. Many different motor types have been qualitatively compared and can be found in the literature. To guide appropriate component selection, this paper presents details of a quantitative study for a given electric propulsion drive system. A Pareto optimal front for a notional drive system of a 1.5 MW electrical propulsor with different motor types is generated and compared. An optimization algorithm coupled with an electromagnetic finite element analysis software tool was used to optimize the induction motor, switched reluctance motor, wound rotor synchronous motor, permanent magnet synchronous motor (PMSM), slotless PMSM, permanent-magnet-assisted synchronous reluctance motor, brushless DC motor, and brushless doubly fed reluctance motor types for efficiency and specific power. Overall advantages considering system-level efficiency, specific power, and a few other key metrics such as origin of losses, cooling complexity, manufacturing tolerance, and fault tolerance are discussed. This gives an indication of the relative performance of different motor types and confirms the overall advantage of PM motor topologies in aircraft propulsion.

关键词： Aircraft Propulsion System Switched Reluctance Motor Finite Element Analysis Electric Propulsion optimization algorithm Thermal Management System Fault Tolerance Software Tool Hybrid Electric Aircraft Torque Ripple

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Hybrid-scheduling-based sliding mode control for Markovian jump systems under transmission constraints

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JOURNAL OF THE FRANKLIN INSTITUTE-ENGINEERING AND APPLIED MATHEMATICS 2024年第5期361卷

作者： Zhang, Ying Chen, Bei Shanghai Univ Engn Sci Shanghai 201620 Peoples R China

This paper presents a new hybrid -scheduling -based design of sliding mode control for Markovian jump systems against transmission constraints. The hybrid scheduling scheme integrates stochastic communication protocol and event -triggering mechanism. At each transmission instant, a discrete -time Markovian chain is employed to orchestrate the stochastic transmission of multiple sensor nodes, by which only one sensor node has the priority to be evaluated whether it meets the triggering condition to access the network. This hybrid scheduling scheme aims to generate a sparser sampling pattern than the existing one while improving channel resource utilization. Based on which a feasible compensator and token -dependent sliding mode controller is constructed. Moreover, a genetic algorithm -based optimization problem is given to achieve a smaller convergent domain. Finally, a numerical example is shown to verify the present control strategy.

关键词： Communication scheduling protocol Event-triggering (ET) strategy Markovian jump systems (MJSs) optimization algorithm Sliding mode control (SMC)

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An algorithm to optimize the optical sensor design for tip clearance and tip timing measurements 7

An algorithm to optimize the optical sensor design for tip c...

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Conference on Optical Sensing and Detection VII Part of SPIE Photonics Europe Conference

作者： Zubia, Gorka Amorebieta, Josu Zubia, Joseba Durana, Gaizka Univ Basque Country Dept Commun Engn Plaza Ingeniero Torres Quevedo 1 E-48013 Bilbao Basque Country Spain

ISBN: (纸本)9781510651555;9781510651548

In this work, an algorithm for the optimization of the design of an optical fiber bundle displacement sensor for Tip Clearance and Tip Timing measurements is presented. The former is based on the gaussian beam mathematical approach, and implements a fiber arrangement comprised of a transmitting single-mode fiber and two concentric rings of receiving multimode fibers. The software includes a graphical user interface that allows modifying relevant geometrical parameters of the sensor and fiber characteristics, and enables monitoring in real time the effects of such modifications. Results indicate that in order to achieve the most sensitive design with the largest operating range, the key parameters are the gain configuration, the distance between the receiving fiber rings and the radii of receiving fibers, and that the best fitting sensor configuration is a tradeoff among the aforementioned characteristics as it is heavily dependent on the measurement constraints. The results obtained by the simulation tool were validated in good agreement with the calibration curve of the manufactured optical fiber bundle displacement sensor in a scaled rotor.

关键词： optical fiber sensor optimization algorithm tip clearance tip timing aircraft turbines displacement measurement

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Symmetric Cryptography With a Chaotic Map and a Multilayer Machine Learning Network for Physiological Signal Infosecurity: Case Study in Electrocardiogram

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IEEE ACCESS 2021年 9卷 26451-26467页

作者： Lin, Chia-Hung Wu, Jian-Xing Chen, Pi-Yun Li, Chien-Ming Pai, Neng-Sheng Kuo, Chao-Lin Natl Chin Yi Univ Technol Dept Elect Engn Taichung 41170 Taiwan Chi Mei Med Ctr Dept Med Div Infect Dis Tainan 41710 Taiwan Natl Kaohsiung Univ Sci & Technol Dept Maritime Informat & Technol Kaohsiung 80543 Taiwan

Digital physiological signals in telecare medicine information systems have been widely applied in remote medical applications, such as telecare, tele-examination, and telediagnosis, via computer networking transmission or wireless communication. However, these medical records need to ensure authorization demands in the channel model for human body communication and remote medical servers and enhance the confidentiality, recoverability, and availability of transmission data. Hence, this study proposes a symmetric cryptography scheme with a chaotic map and a multilayer machine learning network (MMLN) to achieve physiological signal infosecurity. A chaotic pseudorandom number generator within specific control parameters can dynamically produce unordered sequence numbers to set the secret keys for a regular secret key update, thereby improving the security of private cipher codes. The chaotic map is quickly iterated to produce a pseudorandom key stream for real-time applications, and the private cipher codes are selected using the initial and specific control parameters at the data emitter and receiver ends. A general regression neural network is used to map the high-dimensional input-output pair of cipher codes for substitution and permutation processes. Its adaptive MMLN with an optimization algorithm can rapidly train the random cipher code protocol to achieve an encryptor and a decryptor for a regular encrypted communication. Using the Massachusetts Institute of Technology-Beth Israel Hospital (MIT-BIH) Arrhythmia Database, 100 electrocardiogram fragments are used to verify the proposed model, and the peak signal-to-noise ratio (PSNR) as a quantitative quality metric is used to evaluate the visual quality after encryption and decryption processes for further diagnosis applications. Experimental results show that the proposed scheme has a higher mean PSNR (35.26 +/- 3.77 dB) and shorter mean executing time (0.16 +/- 0.01 s) compared with traditional cryptography pro

关键词： Electrocardiography Chaotic communication Ciphers Protocols Measurement Encryption Wireless communication Symmetric cryptography chaotic map general regression neural network optimization algorithm peak signal-to-noise ratio

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Application of Self-adaptive Vision-Correction algorithm for Water-Distribution Problem

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KSCE JOURNAL OF CIVIL ENGINEERING 2021年第3期25卷 1106-1115页

作者： Lee, Eui Hoon Chungbuk Natl Univ Sch Civil Engn Cheongju 28644 South Korea

Water is one of the essential elements in human life, and the water-distribution system is an important infrastructure that distributes water to the people. The design of the water-distribution system was done manually in the past, but recently, it was conducted by applying optimization algorithms. Various optimization algorithms were developed for the optimal design of the water-distribution system, but there was a disadvantage to perform sensitivity analysis for parameter estimation manually. A vision-correction algorithm (VCA) was developed to emulate the conventional manual vision-correction procedure, and it exhibited a good performance in many mathematical benchmark and civil engineering problems. However, the VCA has limited usefulness because of its large number of parameters, many of which require estimation. In this study, a self-adaptive VCA (SAVCA) was developed to overcome these shortcomings by modifying the parameters of the VCA to be self-adaptive or fixed. The Balerma network - a water-distribution system - was selected as a civil engineering problem. The results of SAVCA were better than those of other methods for the design of Balerma network. The SAVCA exhibited good usability and performance and can be applied to various fields in civil engineering including the water-distribution system.

关键词： Water-distribution system Civil engineering problem Metaheuristic Self-adaptive Vision correction optimization algorithm

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Tour Design Using Resonant-Orbit Invariant Manifolds in Patched Circular Restricted Three-Body Problems

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2021年第1期44卷 106-119页

作者： Anderson, Rodney L. CALTECH Jet Prop Lab 4800 Oak Grove DrM-S 301-121 Pasadena CA 91109 USA

It is increasingly desirable to incorporate multibody effects in tour design early in the process to both discover new solutions and reduce the number and size of required maneuvers. Flybys have previously been designed using the heteroclinic connections of resonant orbits in the circular restricted three-body problem (CRTBP), but tour design often requires the consideration of additional moons, especially within the Jovian system. In this study, the heteroclinic connections of multiple resonant orbits are chained together within separate CRTBP models to perform multiple flybys that advance through desired resonances. Methods for patching these trajectories together are explored, and sample trajectories are computed.

关键词： Ganymede Orbital Period Computing optimization algorithm Numerical optimization Keplerian Orbit Libration Points Astrodynamics Astronomy Earth

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Research on 3D Laser Scanning Monitoring Method for Mining Subsidence Based on the Auxiliary for Probability Integral Method

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KSCE JOURNAL OF CIVIL ENGINEERING 2021年第11期25卷 4403-4416页

作者： Lei Wang Zhu Shangjun Jiang Chuang Li Jingyu Jiang Kegui Teng Chaoqun Wei Tao Guo Qing-biao Anhui Univ Sci & Technol Sch Geomat Huainan 232001 Peoples R China Anhui Univ Sci & Technol Sch Earth & Environm Huainan 232001 Peoples R China China Univ Min & Technol Sch Environm & Geoinformat Xuzhou 221116 Jiangsu Peoples R China

When 3D laser scanning technology is used to monitor the surface deformation of mining subsidence in mining area, the surface of the working face is covered with a large number of vegetation, and the surface water accumulates above the working face, which makes the point cloud data obtained by the 3D laser scanning difficult to denoise, or even missing. At this time, the conventional 3D laser scanning technology can not obtain the surface deformation field of mining subsidence. Aiming at the above problems, the 3D laser scanning monitoring method for mining subsidence based on the auxiliary for PIM proposed (3DLS-PIM). Firstly, this paper introduces the PIM prediction model. Secondly, the mining subsidence observation equation based on 3DLS-PIM is constructed, and then the prediction parameters of PIM are solved based on quantum particle swarm optimization (QPSO). Finally, according to the PIM and its parameters, the mining subsidence surface deformation basin is predicted and obtain the surface deformation field of mining subsidence. Robust experiments show that QPSO has a certain ability to resist random errors and gross errors. The results of engineering application show that the mining area 3D deformation monitoring method proposed in this paper has certain engineering application value.

关键词： Mining subsidence Probability integral method 3D laser scanning technology Quantum particle swarm optimization algorithm Deformation monitoring

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