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Two points are enough

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arXiv

arXiv 2024年

作者： Liu, Hao Zhao, Yanbin Zheng, Huarong Fan, Xiulin Deng, Zhihua Chen, Mengchi Wang, Xingkai Liu, Zhiyang Lu, Jianguo Chen, Jian State Key Laboratory of Fluid Power Components and Mechatronic Systems School of Mechanical Engineering Zhejiang University Hangzhou China Ocean College Zhejiang University Hangzhou China State Key Laboratory of Silicon and Advanced Semiconductor Materials School of Materials Science and Engineering Zhejiang University Hangzhou China Nanyang Technological University Singapore School of Control Science and Engineering Zhejiang University Hangzhou China School of Materials Science and Engineering Tianjin University Tianjin China School of System Design and Intelligent Manufacturing Southern University of Science and Technology Shenzhen China

Prognosis and diagnosis play an important role in accelerating the development of lithium-ion batteries, as well as reliable and long-life operation. In this work, we answer an important question: What is the minimum amount of data required to extract features for accurate battery prognosis and diagnosis? Based on the first principle, we successfully extracted the best two-point feature (BTPF) for accurate battery prognosis and diagnosis using the fewest data points (only two) and the simplest feature selection method (Pearson correlation coefficient). The BTPF extraction method is tested on 820 cells from 6 open-source datasets (covering five different chemistry types, seven manufacturers, and three data types). It achieves comparable accuracy to state-of-the-art features in both prognosis and diagnosis tasks. This work challenges the cognition of existing studies on the difficulty of battery prognosis and diagnosis tasks, subverts the fixed pattern of establishing prognosis and diagnosis methods for complex dynamic systems through deliberate feature engineering, highlights the promise of data-driven methods for field battery prognosis and diagnosis applications, and provides a new benchmark for future studies. Copyright © 2024, The Authors. All rights reserved.

关键词： Lithium-ion batteries

Liquid Metal Manifold Microchannel Heat Sink for Ultra-High Heat Flux Cooling

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SSRN 2024年

作者： Zhang, Mingkuan Gao, Qi Zhao, Zhiyuan Guo, Luna Li, Xuan Zhang, Chao Zhang, Xudong Rao, Wei Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin300384 China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of Technology China School of mechanical engineering Tianjin University of Commerce Tianjin300134 China Institute of Refrigeration and Cryogenics Shanghai Jiao Tong University Shanghai200240 China Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering Mechanics Tsinghua University Beijing Beijing100084 China CAS Key Laboratory of Cryogenics Technical Institute of Physics and Chemistry Chinese Academy of Sciences China Beijing Key Lab of CryoBiomedical Engineering and Key Lab of Cryogenics Beijing100190 China

The reduction in transistor dimensions and advancements in chip integration have led to a dramatic increase in the heat flux of chip. Advanced heat dissipation technology has become the pivotal in ensuring the normal operation of chips and fully utilizing chip performance. Room temperature liquid metal convection cooling technology has demonstrated its efficacy as a viable approach for addressing high heat flux heat dissipation. However, the smaller specific heat capacity of liquid metal leads to a large temperature rise, imposing a constraint on the progression of liquid metal cooling technology. To overcome this drawback, this paper proposed a liquid metal manifold channel structure designed to convert the continuous long-range flow into a segmented short-range flow. The good matching between liquid metal and manifold structures is adequately demonstrated through a comparison with alternative coolant and channel structure. The simulation results demonstrate the effectiveness of liquid metal manifold channel cooling in dealing with a heat flux of 1000 W/cm², ensuring that the maximum temperature of the chip remains below 351.7 K. Moreover, the convective heat transfer coefficient even reaches 106 W/(m2·K), which is ten times larger than that of water conventional microchannel heat sink. The orthogonal experiments were conducted to analyze how the structural parameters affect the dissipation performance, including the height of the microchannel, ratio of manifold length to fin length, length of fin in manifold, width of channel, and ratio of fin with to channel width. It concluded that the height of the microchannel has been identified as the most critical factor. This manifold structure mitigates the inherent limitation of the lower specific heat capacity of liquid metal, paving the way for effective thermal management of electronic devices subjected to ultra-high heat flux. © 2024, The Authors. All rights reserved.

关键词： Heat flux

Nonlinear Modeling and Sensitivity Performance Analysis of a Novel Tapered Beam-Based Micro-Gyroscope

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SSRN 2022年

作者： Zhang, Kunpeng Xie, Jianwei Hao, Shuying Feng, Jingjing Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin300384 China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of Technology Tianjin300384 China

In this paper, we investigate a class of tapered beam micro-gyroscope with electrostatically driven and consider the effects of electrostatic force nonlinearity and fringing field. The governing equations of system are derived by Euler angular transformation and Hamilton principle. The ordinary differential equations with fourth-order variable coefficient are solved by the Adomian decomposition method (ADM). Influence of parameters such as shape factors and DC voltage on static deflection, pull-in voltage and natural frequency of tapered beam micro-gyroscope are investigated. Galerkin discretization is performed on the governing equations of the tapered beam micro-gyroscope. The frequency-response equation of the system is deduced and solved by applying the method of multi-scale (MMS). We obtained the influence regular of DC voltage and fringing field effect on the frequency-response curves. Finally, performance of the tapered beam micro-gyroscope is analyzed in terms of bandwidth, sensitivity, and calibration curve nonlinearity under different shape factors. In static analysis, the pull-in voltage of system gradually decreases with the increase of the shape factors of tapered beam micro-gyroscope, and it will be further reduced by considering the fringing field effect. In the dynamic analysis, the maximum amplitude of motion in the drive and sense directions increases significantly with the shape factors of the tapered beam. Softening characteristics caused by the nonlinearity of the electrostatic force are enhanced. Compared with straight beam micro-gyroscope, the tapered beam micro-gyroscope has the higher amplitude of motion and pronounced nonlinear characteristics. Due to the nonlinearity, the frequency-response curves in the drive direction shifts to the left. The amplitude of motion in the drive direction has a high response over a wide frequency band. By controlling the DC voltage, the natural frequency of the sense mode is matched with the nonlinear natural

关键词： Bandwidth

Thermal-Economic Optimization and Working Fluid Selection of Subcritical Organic Rankine system for Low-Temperature Waste Heat Recovery

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SSRN 2022年

作者： Zhang, Chao Li, Yongwang Fu, Wencheng Zhiting, Tong Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin300384 China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of Technology Tianjin300384 China

In the present study, multi-objective optimization is conducted to search for the best operating condition for a subcritical organic Rankine system with the trade-off between system exergy efficiency and dynamic payback period (PBP). A 150°C wastewater heat source is employed as a typical low-temperature heat source. Five decision variables are considered: turbine inlet temperature and pressure, pinch point temperature differences in evaporator and condenser, and condensing temperature. The multi-objective genetic algorithm combined with the backpropagation neural network method is employed as the optimization approach. In addition, the improved Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) is developed to gain the optimal Pareto front solution for either working fluid and find the optimal working fluid among the candidates investigated. The results show that working fluid R236fa is the optimal solution, despite the minimum PBP for working fluid R123 and the maximum system exergy efficiency for working fluid R1234ze. Under the optimal working condition for working fluid R236fa, the system exergy efficiency and the PBP are 0.465 and 7.377 years, respectively. © 2022, The Authors. All rights reserved.

关键词： Multiobjective optimization

Research on Feedforward Control Based on Robot Dynamics Parameters Identification 17

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Research on Feedforward Control Based on Robot Dynamics Para...

17th IEEE International Conference on Mechatronics and Automation, ICMA 2020

作者： Shao, Xingmao Wang, Shoujun Yang, Liusong Liu, Nan Tianjin University of Technology Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control Tianjin300384 China Citic Heavy Industries Company Ltd. Luoyang471003 China

ISBN: (纸本)9781728164151

Accurate robot dynamics model can effectively improve the motion control performance of robot, and accurate dynamics parameters are the basis for establishing dynamics model. This paper discusses the parameter identification method of the tandem manipulator and the feedforward control scheme based on dynamics. First, we deduced the basic parameters of the first three joints of the UR5 manipulator, and identified the parameters through experimental sampling and calculation. Secondly, we established a feedforward control mechanism based on dynamics using the Simulink platform, and simulated and verified the feedforward control of the robot three-axis system. The experimental results show that the feedforward control scheme based on robot dynamics can effectively improve the error convergence performance, which proves the effectiveness of the method. © 2020 IEEE.

关键词： Manipulators

Building Energy Efficiency Assessment Base on Predict-Center Criterion Under Diversified Conditions

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SSRN 2023年

作者： Liao, Xuechao Zheng, Xiujuan Ping, Zouwei Zhao, Haoyi Wang, Ning Zhang, Yong School of Computer Science and Technology Wuhan University of Science and Technology Wuhan430080 China Hubei Province Key Laboratory of Intelligent Information Processing and Real-time Industrial System Wuhan430080 China School of Information Science and Engineering Wuhan University of Science and Technology Wuhan430080 China National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Wuhan430030 China WISDRI City Construction Engineering &Research Incorporation Ltd. Wuhan430030 China Changjiang Institute of Survey Planning Design and Research Wuhan430010 China

With the rapid expanding of urban economy and population, how to reduce the energy consumption and improve energy efficiency of public buildings has become a key issue for energy conservation and urban development. However, due to the diversity of building employing condition, energy consumption data often has problems with nonlinearity, outliers, and diversity, which will greatly reduce the accuracy of energy consumption prediction and energy conservation assessment. To overcome the above drawbacks, a regression prediction model of building energy consumption is designed, which cluster the same type of data characteristics to form a subset of equipment through Gaussian mixture clustering, and design the specific normalized adaptive loss function to determine the optimal control parameters of regression model. Furthermore, a novel predict-center energy efficiency evaluation criterion is proposed, and the cumulative distribution pattern is further statistically analyzed. Finally, the energy benchmark evaluation framework is proposed to determine the energy efficiency evaluation grade. Through comparative experimental analysis, it can be seen that the proposed prediction model can adapt to different types of building data, and have better prediction accuracy and convergence speed. The consistency and robustness of the benchmark evaluation framework and method are optimal. © 2023, The Authors. All rights reserved.

关键词： Energy utilization

Communication-Assisted Sensing in 6G Networks

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arXiv

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

An Ontology-based Knowledge Modeling towards Eco-design for Additive Manufacturing

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Procedia CIRP 2024年 122卷 760-765页

作者： Yanan Wang Tao Peng Samyeon Kim Yi Xiong Yunlong Tang Renzhong Tang State Laboratory of Fluid Power Components and Mechatronic Systems School of Mechanical Engineering Zhejiang University Hangzhou 310058 China Department of Mechanical Engineering Jeonju University Jeonju-si Jeollabuk-do 55069 South Korea School of System Design and Intelligent Manufacturing Southern University of Science and Technology Shenzhen 518055 China Mechanical and Aerospace Engineering Department Monash University Melbourne 3800 Australia Materials Science and Engineering Department Monash University Melbourne 3800 Australia Zhejiang Province Key Laboratory of Advanced Manufacturing Technology School of Mechanical Engineering Zhejiang University Hangzhou 310058 China

Owing to the unique technological merits of additive manufacturing (AM), design for AM, particularly eco-design for AM, has been gaining attention in improving the sustainable performance of AM-fabricated (AMed) parts. The main challenge in harvesting potential sustainability benefits is how to capture the impact of design on sustainable performance. Though several existing studies adopted quantitative evaluation on AM sustainability and investigated the relationships between design information and sustainability information of AMed part, the sustainability information is still unavailable in the design phase. This hardly guides eco-design for AM in practice. To support the increasing industrial applications of AM, this paper illustrates related knowledge, that is, material-process-structure-ecoProperty (MPSeP) relationships to connect design and sustainability information in eco-design for AM. An ontology-based method is proposed to model the MPSeP relationships of the AMed part in a structured way. An example of an AMed hydraulic valve body was used to demonstrate the MPSeP modeling process. It is discussed that how the constructed model effectively assists AM designers through providing eco-design recommendation, and enables design software tools to perform sustainability analysis towards eco-design for AM.

关键词： additive manufacturing eco-design for additive manufacturing ontology model sustainability

Robust Output Synchronization of Discrete-Time Linear-Time-Invariant Multi-Agent systems Using Phase Tool

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Robust Output Synchronization of Discrete-Time Linear-Time-I...

European Control Conference (ECC)

作者： Xin Mao Dan Wang Wei Chen Li Qiu School of System Design and Intelligent Manufacturing Southern University of Science and Technology Shenzhen China Division of Decision and Control Systems KTH Royal Institute of Technology Stockholm Sweden Department of Mechanics and Engineering Science State Key Laboratory for Turbulence and Complex Systems Peking University Beijing China Southern University of Science and Technology Shenzhen China Hong Kong University of Science and Technology Hong Kong S.A.R. China

ISBN: (数字)9783907144107

ISBN: (纸本)9798331540920

In this paper, the output synchronization in large-scale discrete-time networks is examined by utilizing the novel phase tool, where the agent dynamics are allowed to be significantly heterogeneous. The synchronization synthesis problem is formulated and thoroughly investigated, with the goal of characterizing the allowable heterogeneity among the agents to ensure synchronization under a uniform controller. The solvability condition is provided in terms of the phases of the residue matrices of the agents at the persistent modes. When the condition is satisfied, a design procedure is given, producing a low-gain synchronizing controller. Numerical examples are given to illustrate the results.

关键词： Sufficient conditions Europe Heterogeneous networks Synchronization Multi-agent systems