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Prediction of Back-layering Length and Critical Velocity with Lithium-ion Battery Car Fires in Tunnel

IAENG International Journal of Applied Mathematics 2024年第6期54卷 1033-1037页

作者： Bai, Zhenpeng Zhao, Xiaohan Song, Huaitao Zhang, Yang Yao, Haowei Zhang, Jin Department of Zhengzhou Key Laboratory of Electric Power Fire Safety College of Building Environment Engineering Zhengzhou University of Light Industry China Department of Financial Management Henan Light Industry Vocational College Zhengzhou China Department of College of Building Environment Engineering Zhengzhou University of Light Industry China Department of School of Electrical and Information Engineering Henan University of Engineering China Department of College of Building Environment Engineering Zhengzhou University of Light Industry Zhengzhou450002 China Department of Beijing Key Laboratory of Control Technology for City Toxic and Combustible Major Hazards Institute of Urban Safety and Environmental Science Beijing Academy of Science and Technology Beijing100054 China

The purpose of this article is is to investigate the critical speed and back-layer length of smoke propagation during fires of lithium-ion battery vehicles in tunnels. The combustion of lithium-ion battery vehicles in tunnels is numerically simulated. This article uses heat release rate (HRR) and ventilation rate to predict the length of smoke counterflow in tunnel fires with new energy vehicles. Temperature is an important parameter for calculating smoke counterflow. The temperature in the tunnel is measured by thermocouples. The results showed that dimensionless critical velocity influences dimensionless HRR. The numerical simulation results indicated that there is a certain correlation between the HRR variable, which corresponds to the dimensionless smoke counterflow length and the critical speed in the tunnel. This article proposed a computational model for predicting the length of smoke counterflow. This paper contributes to the prevention of tunnel fires and reduction of social and economic losses. Therefore, this paper guides the propagation of smoke under the roof of lithium-ion battery vehicle fires in tunnels. © (2024), (International Association of Engineers). All rights reserved.

关键词： Ions

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Design and preparation of aluminum alloy with high thermal conductivity based on CALPHAD and first-principles calculation

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China Foundry 2022年第3期19卷 225-237页

作者： Ye Wang Hui-jun Kang Yu Guo Hong-tao Chen Mao-liang Hu Ze-sheng Ji School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150004China Key Laboratory of Materials Modification by Laser Ion and Electron Beams(Dalian University of Technology)Ministry of EducationDalian 116024LiaoningChina Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116024LiaoningChina School of Science and Engineering Huzhou CollegeHuzhou 313000ZhejiangChina

To obtain the aluminum alloy with high thermal and mechanical properties,the effects of alloying elements and the second phases on the thermal conductivity of Al alloys were investigated by CALPHAD and first-principles calculation,*** properties of the second phases,including Young's modulus,Poisson's ratio and minimum thermal conductivity,were systematically *** show that the ranking order of the effects of the alloying elements on the thermal conductivity is Mg>Cu>Fe>Si,and for Al-12Si alloys,the mathematical model of the relationship between the alloying elements and the thermal conductivity can be expressed as λ=ax^(2)-bx+c when the second phase precipitates in the *** kinds of ternary phases of Al-Fe-Si have higher deformation resistance,rigidity,theoretical hardness,Debye temperature and thermal conductivity than the other phases which possibly exist in the Al-12Si *** on the guidance of CALPHAD and first-principles calculation,the optimized chemical composition of Al alloy with high conductivity is Al-11.5Si-0.4Fe-0.2Mg(wt.%)with a thermal conductivity of 137.50 W·m^(-1)·K^(-1)and a hardness of 81.3 HBW.

关键词： design and preparation CALPHAD first-principles calculation thermal conductivity aluminum alloy

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Research on Optimization Method of Injection Molding Machine Temperature control System Based on IK-SS

Research on Optimization Method of Injection Molding Machine...

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Chinese Automation Congress (CAC)

作者： Haipeng Zou Quanxiang Ye Xiaoyu Li Xiangsong Kong Dan Zhao Zhijiang Shao School of Electrical Engineering and Automation Xiamen University of Technology Xiamen China State Key Laboratory of Industrial Control Technology Zhejiang University Hangzhou China Zhangzhou Hongxingtai Electronics Co. Ltd China College of Control Science and Engineering and State Key Laboratory of Industrial Control Technology Zhejiang University Hangzhou China

ISBN: (数字)9798350368604

ISBN: (纸本)9798350368611

Injection molding, as a plastic processing technology, is widely used in the mass production of plastic products with high precision and automation. However, the performance optimization process of this system currently faces some prominent issues, such as time consumption, reliance on experience, and difficulty in achieving optimality. Traditional optimization methods typically rely on manual experience and rules, which are inefficient and time-consuming. To enhance the performance of the control system, this paper focuses on utilizing an improved simplex search method based on the data-driven optimization concept to optimize the parameters of the temperature control system of the injection molding machine. The method introduced in this paper is termed the Knowledge-Informed Simplex Search Method Based on Adjacent Historical Centroid Points Information (IK-SS). The IK-SS algorithm is a variant of the simplex search method that utilizes information from the centroids of neighboring simplices to evaluate the current state of the optimization process and dynamically adjust the iteration step size. This approach aims to improve optimization efficiency while reducing computational complexity and time costs. Simulation and experimental validation demonstrate that the IK-SS algorithm significantly enhances the temperature control performance of the injection molding machine (IMM). This demonstrates the potential of the IK-SS algorithm as a tool for optimizing the temperature control system of injection molding machines.

关键词： Systematics Automation Search methods Heuristic algorithms System performance Optimization methods Injection molding Temperature control Plastics Tuning

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Development of Methylene Bis-Benzotriazolyl Tetramethylbutylphenol-grafted lignin sub-microspheres loaded with TiO_(2) for sunscreen applications

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Journal of Bioresources and Bioproducts 2024年第4期9卷 534-547页

作者： Yarong Li Zhiguang Tang Xiaohan Zhou Junhua Zhang Xueping Song Kai Li Wei Liu Zhanying Zhang College of Light Industry and Food Engineering Guangxi UniversityNanning530004China Province and Ministry Co-Sponsored Collaborative Innovation Center of Cane Sugar Industry Nanning530004China Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources College of Chemical EngineeringNanjing Forestry UniversityNanjing210037China Guangxi Key Laboratory of Clean Pulp&Papermaking and Pollution Control Nanning530004China Tianjin Key Laboratory of Pulp&Paper Tianjin University of Science&TechnologyTianjin300457China School of Mechanical Medical and Process EngineeringCentre for Agriculture and the BioeconomyQueensland University of TechnologyQueensland4000Australia

Lignin serves as a promising Ultraviolet(UV)absorber within sunscreen ***,the commercial development of lignin-containing sunscreens faces challenges due to their low sun protection factor(SPF)and dark color in cosmetics *** this study,dual modifications on the chemical and physical structures of lignin were conducted to address these ***,methylene bis-benzotriazolyl tetramethylbutylphenol(MBBT)was grafted onto alkali lignin(AL)through an atom transfer radical polymerization reaction,resulting in a polymer of AL-graft-MBBT_(3)(AL-g-MBBT_(3)).The sunscreen prepared with 10%AL-g-MBBT_(3) displays outstand-ing sun protection performance with a SPF of 42.93 and a light color with a color difference value(ΔE)of 45.6,in contrast to 10%AL with a SPF of 4.74 and aΔE value of ***,AL-g-MBBT_(3) was transformed into normal submicron spheres(AL-g-MBBT_(3) N)and TiO_(2)-loading submicron spheres(AL-g-MBBT_(3)/TiO_(2)).The sun protection performances of 10%AL-g-MBBT_(3) N@C and AL-g-MBBT_(3)/TiO_(2)@C sunscreens obviously surpass that of AL-g-MBBT_(3)@C sunscreen,achieving SPFs of 60.38 and 66.20,***,there is a considerable improve-ment in the color of these sunscreens,withΔE values of 41.8 and 36.3,*** results provide valuable insights into exploring lignin’s high-value applications in sunscreen.

关键词： Lignin Graft Submicron sphere TiO_(2) Anti-UV performance Color

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ENABLING HIGH SENSITIVITY AIRFLOW MEASUREMENT USING PHASE-CHANGE MATERIALS 26

ENABLING HIGH SENSITIVITY AIRFLOW MEASUREMENT USING PHASE-CH...

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26th International Conference on Miniaturized Systems for Chemistry and Life sciences, MicroTAS 2022

作者： Zhou, Yushan Cao, Yunqi Sepúlveda, Nelson Zhang, Hongjian State Key Laboratory of Industrial Control Technology College of Control Science and Engineering Zhejiang University Zhejiang Hangzhou310027 China Department of Electrical and Computer Engineering Michigan State University East LansingMI48824 United States

ISBN: (纸本)9781733419048

A lab-on-a-chip (LOC) thermal mass flow sensor based on microelectromechanical systems (MEMS) technology is designed, fabricated, and characterized. Vanadium dioxide (VO2), a nonlinear phase-change material with 3-order of change in resistance is placed in the down streaming direction of the heat source as the sensing element. The resistance of VO2 is monitored under gas flow rates ranging from 0 to 37.8 μL·s-1 with a maximum sensitivity of 368.56 ppm/(μL·min-1). The studies presented in this research may enable the application of utilizing nonlinear metamaterial in microfluidic LOC sensors with orders of magnitude improvement in sensitivity. © 2022 MicroTAS 2022 - 26th International Conference on Miniaturized Systems for Chemistry and Life sciences. All rights reserved.

关键词： Phase change materials

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Developing Ni-based CO2 methanation catalysts with enhanced low-temperature activities via constructing advantageous mesoporous CeO2 nanosphere support

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Ceramics International 2025年第17期51卷 23908-23924页

作者： Lu, Tianmin Zhu, Zehui Luo, Xue Lian, Linshui Wu, Cai-e Cao, Zhen Zhao, Xin Wu, Mei Xu, Leilei Chen, Mindong Collaborative Innovation Centre of the Atmospheric Environment and Equipment Technology School of Environmental Science and Engineering Nanjing University of Information Science & Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Nanjing210044 China College of Light Industry and Food Engineering Nanjing Forestry University Nanjing210037 China College of Chemical Engineering and Environmental Chemistry Weifang University Weifang261061 China National & Local Joint Engineering Research Centre for Mineral Salt Deep Utilization Huaiyin Institute of Technology Huaian223003 China School of Environment and Energy Engineering Anhui Jianzhu University Hefei230009 China

In this work, the advantageous mesoporous CeO2 nanosphere with large specific surface area up to 190.4 m2/g was facilely prepared using an improved hydrothermal method. The obtained mesoporous CeO2 nanosphere was used as the support for Ni-based CO2 methanation catalysts. The effects of Ni loading, structural properties, and redox characteristics on the catalytic performances were systematically investigated. The catalyst with 20 wt% Ni loading supported on mesoporous CeO2 nanosphere demonstrated exceptional low-temperature activity. A comprehensive suite of characterization techniques, including XRD, N2 physisorption, SEM, XPS, H2-TPR, CO2-TPD, in-situ DRIFTS, and online TPSR, were utilized to elucidate the underlying reasons for the superior performance. The superior activity of the Ni-based catalyst was attributed to the large specific surface area, mesoporous structure, and excellent redox properties of the mesoporous CeO2 nanosphere support. In contrast, Ni-based catalysts supported on commercial materials (e.g., SiO2, Al2O3, CeO2) exhibited poor low-temperature performance due to severe thermal sintering of metallic Ni active sites and inferior redox properties. Therefore, the present mesoporous CeO2 nanosphere with large specific surface area, advantageous redox property, and abundant surface oxygen vacancies are promising supports for Ni-based catalysts, enhancing low-temperature CO2 methanation performance and potentially benefiting other reactions. © 2025 Elsevier Ltd and Techna Group S.r.l.

关键词： Mesopores

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Resilient Time-Varying Formation-Tracking of Multi-UAV Systems Against Composite Attacks: A Two-Layered Framework

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IEEE/CAA Journal of Automatica Sinica 2023年第4期10卷 969-984页

作者： Xin Gong Michael V.Basin Zhiguang Feng Tingwen Huang Yukang Cui School of Cyber Science and Engineering Southeast UniversityNanjing 210096the School of AstronauticsNorthwestern Polytechnical UniversityXi’an 710072 Department of Mechanical Engineering The University of Hong KongHong Kong 999077China School of Physical and Mathematical Sciences the Autonomous University of Nuevo LeonNaevo Leon 66455Mexico Ningbo Institute of Intelligent Equipment Technology Ningbo 315299China College of Intelligent Systems Science and Engineering Harbin Engineering UniversityHarbin 150001China Texas A&M University at Qatar Doha 23874Qatar Guangdong Key Laboratory of Electromagnetic Control and Intelligent Robots the College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518060 Peng Cheng Laboratory Shenzhen 518000China

This paper studies the countermeasure design problems of distributed resilient time-varying formation-tracking control for multi-UAV systems with single-way communications against composite attacks,including denial-of-services(DoS)attacks,false-data injection attacks,camouflage attacks,and actuation attacks(AAs).Inspired by the concept of digital twin,a new two-layered protocol equipped with a safe and private twin layer(TL)is proposed,which decouples the above problems into the defense scheme against DoS attacks on the TL and the defense scheme against AAs on the cyber-physical ***,a topologyrepairing strategy against frequency-constrained DoS attacks is implemented via a Zeno-free event-triggered estimation scheme,which saves communication resources *** upper bound of the reaction time needed to launch the repaired topology after the occurrence of DoS attacks is ***,a decentralized adaptive and chattering-relief controller against potentially unbounded AAs is ***,this novel adaptive controller can achieve uniformly ultimately bounded convergence,whose error bound can be given *** practicability and validity of this new two-layered protocol are shown via a simulation example and a UAV swarm experiment equipped with both Ultra-WideBand and WiFi communication channels.

关键词： Composite attacks multi-UAV systems resilient control time-varying formation-tracking

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Self-triggered model predictive control for switched systems with dwell time constraints

Self-triggered model predictive control for switched systems...

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Youth Academic Annual Conference of Chinese Association of Automation (YAC)

作者： Fusen Zhang Jie Lian Feiyue Wu Key Laboratory of Intelligent Control and Optimization for Industrial Equipment Ministry of Education and the School of Control Science and Engineering Dalian University of Technology Dalian China

ISBN: (数字)9798350379228

ISBN: (纸本)9798350390780

This paper proposes a new self-triggered model predictive control (MPC) strategy for switched systems under dwell time (DT) constraints. The strategy combines the advantages of self-triggering mechanism and switching control, thereby having a good performance in saving computing resources and adapting to complex engineering practices. To guarantee the feasibility of the switched MPC strategy under the self-triggering framework, the concept of feasible truncated admissible switching sequence (f-TAS) is proposed to solve the constraint violation problem caused by the switching behavior and guarantee the flexible index. Besides, the self-triggering mechanism is developed to overcome the divergence of the Lyapunov function by using the self-triggered relaxation, thus ensuring the sub-optimal performance. Simulation example shows that the algorithm effectively saves the computing resources while ensuring the feasibility and sub-optimal performance.

关键词： Switched systems Automation Stability criteria Switches Prediction algorithms control systems Time factors

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A Study on Task Offloading Based on Multi-Agent Advantage Actor Critic Algorithms in IIoT

A Study on Task Offloading Based on Multi-Agent Advantage Ac...

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Computers and Artificial Intelligence Technologies (CAIT), International Conference on

作者： Yanchao Xu Zheng Lv Jun Zhao Key Laboratory of Intelligent Control and Optimization for Industrial Equipment Ministry of Education School of Control Science and Engineering Dalian University of Technology Dalian China

ISBN: (数字)9798331530891

ISBN: (纸本)9798331530907

With the rapid development of Industry 4.0, resource-constrained industrial devices are often unable to meet different demands of compute-intensive and latency-sensitive tasks in modern factories. To cope with this challenge, offloading tasks from industrial devices to edge servers or a cloud computing center to obtain lower delay is a good solution. Most of the traditional task offloading approaches rely on centralized decision-making systems, which may not be able to efficiently cope with device heterogeneity and the specific needs of different tasks in industrial environments. To address this problem, this study proposes a more comprehensive edge computing network model for industrial Internet of Things (IIoT). By integrating an action masking technique, we establish a Markov decision model with a constrained action space. Additionally, we propose a task offloading framework based on the Multi-Agent Advantage Actor Critic (MAA2C) algorithm, adopting the Centralized Training Decentralized Execution (CTDE) architecture, aiming to achieve task offloading decision-making in modern factories and reduce the overall system delay. Validated through numerical simulation experiments, our proposed framework not only performs well in reducing system delay but also shows good adaptability in different industrial environments.

关键词： Training Computational modeling Decision making Computer architecture Numerical simulation Production facilities Delays Servers industrial Internet of Things Edge computing

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Calculation model for kinetic energy and rock burst risk evaluation method during roadway excavation

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International Journal of Mining science and technology 2025年第5期35卷 677-690页

作者： Tan, Yunliang Tan, Yan Guo, Weiyao Li, Bo He, Shudong Zhang, Lei Zhang, Yujiang Zhang, Qiuyuan College of Energy and Mining Engineering Shandong University of Science and Technology Qingdao266590 China Shandong Key Laboratory of Intelligent Prevention and Control of Dynamic Disaster in Deep Mines Shandong University of Science and Technology Qingdao266590 China School of Civil Engineering Tongji University Shanghai200092 China China Coal Technology & Engineering Group Chongqing Research Institute Chongqing400039 China College of Coal Engineering Shanxi Datong University Datong037003 China College of Mining Engineering Taiyuan University of Technology Taiyuan030024 China Yuanbaoshan Open-pit Coal Mine Inner Mongolia Pingzhuang Coal Group Co. Ltd. Chifeng024076 China

The accumulation and release of deformation energy within the rock mass of a roadway are primary contributors to the occurrence of rock bursts. This study introduces a calculation model for the kinetic energy generated during roadway excavation, which is based on the fracture and energy states of the rock mass. The relationships among the mining depth, width of the plastic zone, rebound range of the roof and floor, stress concentration factor, and the induced kinetic energy are systematically explored. Furthermore, a rock burst risk evaluation method is proposed. The findings indicate that the energy evolution of the rock mass can be categorized into four stages: energy accumulation due to in-situ stress, energy accumulation resulting from coal compression, energy dissipation through coal plastic deformation, and energy consumption due to coal failure. The energy release from the rock mass is influenced by several factors, including mining depth, stress concentration factor, the width of the plastic zone, and the rebound range of the roof and floor. Within the plastic zone of coal, the energy released per unit volume of coal and the induced kinetic energy exhibit a nonlinear increase with mining depth and stress concentration factor, while they decrease linearly as the width of the plastic zone increases. Similarly, the driving energy per unit volume of the roof and floor shows a nonlinear increase with mining depth and stress concentration factor, a linear increase with the rebound range of the roof and floor, and a linear decrease with the width of the plastic zone. A rock burst risk evaluation method is developed based on the kinetic energy model. Field observations demonstrate that this method aligns with the drilling cuttings rock burst risk assessment method, thereby confirming its validity. © 2025

关键词： Roofs

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