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SSRN 2024年

作者： Wang, Litian Chen, Jie Wang, Shuai Zhou, Tongyao Li, Dan Li, Cuiping Qian, Lirong Xiong, Yang Miao, Lin Xie, Zhiyong Tianjin Key Laboratory of Film Electronic and Communication Devices School of Integrated Circuit Science and Engineering Tianjin University of Technology Tianjin300384 China School of Integrated Circuit Science and Engineering Tianjin University of Technology Tianjin300384 China Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin300384 China China Tianjin Bohua Yongli Chemical Industry CO. Ltd Tianjin30045 China

Protic ionic liquids (PILs) have emerged as innovative solvents with significant potential for CO2 capture and transformation, presenting a sustainable alternative to conventional methods which often involve energy-intensive processes or environmentally detrimental chemicals. Herein, a novel strategy for CO2 capture and conversion at mild conditions using non-stoichiometric protic ionic liquids (NPILs) was demonstrated for the first time. These NPILs, employed as sorbents, solvents, and catalysts, were composed of imidazole (Im) and 1,8-diazabicyclo [5.4.0] undec-7-ene (DBU) in various ratios. Correlations between the mole ratio of DBU/Im and physicochemical properties such as viscosity, conductivity, thermal stability, and the distribution of neutral and ionic species were systematically investigated. Effects of the absorption temperature and CO2 partial pressure on the absorption capacity were also studied. Different absorption mechanisms, including carbonate and carbamate pathways, were analyzed using FT-IR and NMR spectroscopy. Moreover, the fixed CO2 could be catalytically converted to quinazoline-2,4(1H,3H)-diones under exceptionally mild reaction conditions (1atm, 50 °C, metal-free process). A plausible reaction mechanism involving simultaneous CO2 activation and substrate activation for the transformation of CO2 into quinazoline-2,4(1H,3H)-diones was verified through NMR spectra. It is believed that the new insights into the CO2 mechanism will facilitate the rationaldesign of functional ionic liquids for CO2 capture, utilization, and storage in the future. © 2024, The Authors. All rights reserved.

关键词： Carbon dioxide

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Application of Digital Twin Technology in the Teaching of Engineering Drawing Course

Application of Digital Twin Technology in the Teaching of En...

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Information Science and Education (ICISE-IE), International Conference on

作者： Runfeng Zhang Yuxin Tang Zhenzhong Liu Yanfang Sun Jianguo Wu Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of Technology Tianjin China School of Language and Culture Tianjin University of Technology Tianjin China Tianjin Hanhailanfan Marine Technology Co. Ltd. Tianjin China

As an advanced technology that integrates virtuality and reality, digital twin technology has shown a wide range of application prospects in various fields. This paper aims to explore the potential application of digital twin technology in the teaching of engineering drawing courses, to improve students' theoretical knowledge and practical ability. By combining digital twin technology with traditional engineering drawing teaching, students can carry out practical operations and simulations in a virtual environment to better understand and apply drawing concepts and principles. Besides, taking the assembly drawing of thread connection as an actual teaching case, the specific application of digital twin technology in theoretical and experimental teaching is explained, respectively. The results show that digital twin technology is conducive to improving students' interest in engineering drawing courses and training students' spatial imagination ability, which is of great significance to reforming drawing courses.

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Effects of Wall Emissivity on Aerodynamic Heating in Scramjets

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Fluid Dynamics & Materials Processing 2020年第6期16卷 206-216页

作者： Yue Zhou Pengfei Ju School of Aeronautical Science and Technology Beihang UniversityBeijing100191China Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of TechnologyTianjin300384China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education(Tianjin University of Technology) Tianjin300384China

The effects of the wall emissivity on aerodynamic heating in a scramjet are *** supersonic turbulent combustion flow including radiation is solved in the framework of a decoupled strategy where the flow field is determined first and the radiation field *** particular,a finite difference method is used for solving the flow while a DOM(iscrete ordinates method)approach combined with a WSGGM(weighted sum of gray gases)model is implemented for radiative *** nonreactive turbulent channel flows are examined for a DLR hydrogen fueled scramjet changing parametrically the wall *** results indicate that the wall radiative heating rises greatly with increasing the wall *** the wall emissivity rises,the radiative source and total absorption increase,while the incident radiation decreases ***,although the radiative heating can reach a significant level,its contribution to the total aerodynamic heating is relatively limited.

关键词： Scramjet aerodynamic heating wall emissivity radiation

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Hamiltonian Dynamics and Targeted Energy Transfer of a Grounded Bistable Nonlinear Energy Sink

SSRN

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SSRN 2022年

作者： Li, Shuangbao Zhou, Xinxing Chen, Jianen Research Institute of Science and Technology Civil Aviation University of China Tianjin300300 China College of Science Civil Aviation University of China Tianjin300300 China Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin300384 China

A two-degree-of-freedom nonlinear mechanical system describing a damped linear oscillator weakly coupled to a lightweight grounded bistable nonlinear energy sink is proposed to investigate the targeted energy transfer (TET) under asymmetric local nonlinear potentials. The Bogdanov-Takens bifurcations of equilibria are discussed to reflect the bistable and asymmetric characteristics of the system. Through projections of isoenergetic manifolds, the topological features of the Hamiltonian dynamics under $1:1$ internal resonance have been investigated, which induces conditions for energy localization and exchange. In the general case, the topological features of the Hamiltonian dynamics related to the nonlinear normal modes (NNMs) are classified by the Poincare map, the relations between the NNMs and the Hamiltonian dynamics have been interpreted through the frequency energy plots. The results show that introducing the asymmetric characteristics may enhance the TET and realize the complete TET. © 2022, The Authors. All rights reserved.

关键词： Degrees of freedom (mechanics)

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Reliability of organic light-emitting diodes in low-temperature environment

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Chinese Physics B 2020年第12期29卷 112-118页

作者： Saihu Pan Zhiqiang Zhu Kangping Liu Hang Yu Yingjie Liao Bin Wei Redouane Borsali Kunping Guo School of Microelectronics and Control Engineering Changzhou UniversityChangzhou 213164China School of Mechatronic Engineering and Automation Key Laboratory of Advanced Display and System ApplicationsMinistry of EducationShanghai UniversityShanghai 200072China Universdity of Grenoble Alpes CNRSCERMAVF-38000 GrenobleFrance London Centre for Nanotechnology University College LondonLondon WC1H 0AHUK

Organic light-emitting diode(OLED)is an electroluminescent technology that relies on charge-carrier dynamics and is a potential light source for variable environmental ***,by exploiting a self-developed low-temperature testing system,we investigated the characteristics of hole/electron transport,electro-optic conversion efficiency,and operation lifetime of OLEDs at low-temperature ranging from-40℃to 0℃and room temperature(25℃).Compared to devices operating at room temperature,the carrier transport capability is significantly decreased with reducing temperature,and especially the mobility of the hole-transporting material(HTM)and electron-transporting material(ETM)at-40℃decreases from 1.16×10-6 cm2/V·s and 2.60×10-4 cm2/V·s to 6.91×10-9 cm2/V·s and 1.44×10-5 cm2/V·s,***,the temperature affects differently on the mobilities of HTM and ETM,which favors unbalanced charge-carrier transport and recombination in OLEDs,thereby leading to the maximum current efficiency decreased from 6.46 cd·A-1 at 25℃to 2.74 cd·A-1 at-40℃.In addition,blue fluorescent OLED at-20℃has an above 56%lifetime improvement(time to 80%of the initial luminance)over the reference device at room temperature,which is attributed to efficiently dissipating heat generated inside the device by the low-temperature environment.

关键词： organic light-emitting diodes(OLEDs) low temperature reliability operation lifetime

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Rigid-flexible and Fluid-structure Coupling Dynamics of Folding Plate

Rigid-flexible and Fluid-structure Coupling Dynamics of Fold...

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第八届国际振动工程会议

作者： Sanya Chen Wenhua Hu Yalu Zhao Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of Technology National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of Technology

The variable configuration of the folding wings is beneficial to take into account the maneuverability and endurance of the aircraft. During the flight, the elastic deformation and folding motion of the folding wing will induce additional aerodynamic forces, which will produce new deformation and new aerodynamic forces on the wing structure, and this reciprocal coupling will make the folding wing response may tend to diverge and lead to structural damage. In this paper,the principle of geometric similarity is used to simplify the folding wing into a folding plate and study its rigid-flexible aerodynamic coupling dynamics, which has certain practical significance as well as the theoretical value.

关键词： Rigid-flexible and Fluid-structure Coupling Dynamics of Folding Plate

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Multi-Objective Optimal Feedback controls for Under-Actuated Dynamical system

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Journal of Shanghai Jiaotong university(Science) 2020年第5期25卷 545-552页

作者： QIN Zhichang XIN Ying SUN Jianqiao School of Transportation and Vehicle Engineering Shandong University of TechnologyZibo 255000ShandongChina School of Mechanical Engineering Tianjin University of TechnologyTianjin 300384China Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control Tianjin University of TechnologyTianjin 300384China School of Engineering University of California MercedCA 95343USA

This paper presents a study of optimal control design for a single-inverted pendulum(SIP)system with the multi-objective particle swarm optimization(MOPSO)*** proportional derivative(PD)control algorithm is utilized to control the *** the SIP system is nonlinear and the output(the pendulum angle)cannot be directly controlled(it is under-actuated),the PD control gains are not tuned with classical *** this work,the MOPSO method is used to obtain the best PD *** use of multi-objective optimization algorithm allows the control design of the system without the need of linearization,which is not provided by using classical *** multi-objective optimal control design of the nonlinear system involves four design parameters(PD gains)and six objective functions(time-domain performance indices).The HausdorfF distances of consecutive Pareto sets,obtained in the MOPSO iterations,are computed to check the convergence of the MOPSO *** MOPSO algorithm finds the Pareto set and the Pareto front *** simulations and experiments of the rotary inverted pendulum system are done to verify this design *** and experimental results show that the multi-objective optimal controls offer a wide range of choices including the ones that have comparable performances to the linear quadratic regulator(LQR)control.

关键词： multi-objective optimal control under-actuated system particle swarm optimization(PSO) rotary inverted pendulum

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Dual Role of Pulmonary Surfactant Corona in Modulating Carbon Nanotube Toxicity and Benzo[A]Pyrene Bioaccessibility

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SSRN 2023年

作者： Luo, Zhen Xu, Dongfang Xu, Yan Zhao, Jian Hu, Guoqing Yue, Tongtao Department of Engineering Mechanics State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang University Hangzhou310027 China Institute of Coastal Environmental Pollution Control Key Laboratory of Marine Environment and Ecology Ministry of Education Frontiers Science Center for Deep Ocean Multispheres and Earth System Ocean University of China Qingdao266100 China College of Electronic Engineering and Automation Shandong University of Science and Technology Qingdao266590 China

Inhaled carbon nanotubes (CNTs) can deposit in the deep lung, where they interact with pulmonary surfactant (PS) to form coronas, potentially altering the fate and toxicity profile of CNTs. However, the presence of other contaminants in combination with CNTs may affect these interactions. In this study, we investigated the effects of coexisting contaminants, specifically benzo[a]pyrene (BaP), on the interaction between CNTs and PS. We used passive dosing and fluorescence-based techniques to demonstrate that PS increases the solubility of BaP pre-adsorbed on CNTs. Subsequently, molecular dynamics simulations were performed to gain insight into the intricate interactions between CNTs, BaP, and PS. Our results suggest that the PS corona plays a dual role in modulating the toxicity of CNTs. First, it mitigates toxicity by reducing the hydrophobicity and apparent aspect ratio of CNTs. Second, it exacerbates toxicity due to energetically dominant PS-BaP interactions, which increase the solubility and thus bioaccessibility of BaPs. Importantly, these interactions are strongly influenced by the size and aggregation state of the CNTs. Our findings highlight the need to consider the bioaccessibility of coexisting contaminants when assessing the inhalation toxicity of PS-modified CNTs. © 2023, The Authors. All rights reserved.

关键词： Toxicity

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A New Method for Type Synthesis of 2R1T and 2T1R 3-DOF Redundant Actuated Parallel Mechanisms with Closed Loop Units

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Chinese Journal of Mechanical Engineering 2020年第6期33卷 134-157页

作者： Yongquan Li Yang Zhang Lijie Zhang Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan UniversityQinhuangdao066004China Key Laboratory of Advanced Forging&Stamping Technology and Science Ministry of Education of ChinaYanshan UniversityQinhuangdao066004China School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhen518052China Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan UniversityQinhuangdao066004China

The current type synthesis of the redundant actuated parallel mechanisms is adding active-actuated kinematic branches on the basis of the traditional parallel mechanisms,or using screw theory to perform multiple getting intersection and union to complete type *** number of redundant parallel mechanisms obtained by these two methods is *** this paper,based on Grassmann line geometry and Atlas method,a novel and effective method for type synthesis of redundant actuated parallel mechanisms(PMs)with closed-loop units is ***,the degree of freedom(DOF)and constraint line graph of the moving platform are determined successively,and redundant lines are added in constraint line graph to obtain the redundant constraint line graph and their equivalent line graph,and a branch constraint allocation scheme is formulated based on the allocation ***,a scheme is selected and redundant lines are added in the branch chains DOF graph to construct the redundant actuated branch chains with closed-loop ***,the branch chains that meet the requirements of branch chains configuration criteria and F&C(degree of freedom&constraint)line graph are *** this paper,two types of 2 rotational and 1 translational(2R1T)redundant actuated parallel mechanisms and one type of 2 translational and 1 rotational(2T1R)redundant actuated parallel mechanisms with few branches and closed-loop units were taken as examples,and 238,92 and 15 new configurations were *** the mechanisms contain closed-loop units,and the mechanisms and the actuators both have good ***,all the mechanisms have excellent comprehensive performance,in which the two rotational DOFs of the moving platform of 2R1T redundant actuated parallel mechanism can be independently *** instantaneous analysis shows that all mechanisms are not instantaneous,which proves the feasibility and practicability of the method.

关键词： Redundant actuated Parallel mechanisms Type synthesis Atlas method Instantaneous analysis

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Unsignalized Intersection Management Strategy for Mixed Autonomy Traffic Streams

arXiv

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arXiv 2022年

作者： Zhou, Junjie Shen, Zhaokun Wang, Xiaofan Wang, Lin The Department of Automation Shanghai Jiao Tong University Key Laboratory of System Control and Information Processing Ministry of Education of China Shanghai200240 China The Department of Automation Shanghai Jiao Tong University The School of Mechatronic Engineering and Automation Shanghai University The School of Electrical and Electronic Engineering Shanghai Institute of Technology Shanghai201418 China

With the rapid development of connected and automated vehicles (CAVs) and intelligent transportation infrastructure, CAVs, connected human-driven vehicles (CHVs), and un-connected human-driven vehicles (HVs) will coexist on the roads in the future for a long time. This paper comprehensively considers the different traffic characteristics of CHVs, CAVs, and HVs, and systemically investigates the unsignalized intersection management strategy from the upper decision-making level to the lower execution level. The unsignalized intersection management strategy consists of two parts: the heuristic priority queues based right of way allocation (HPQ) algorithm and the vehicle planning and control algorithm. In the HPQ algorithm, a vehicle priority management model considering the difference between CAVs, CHVs, and HVs, is built to design the right of way management for different types of vehicles. In the lower level for vehicle planning and control algorithm, different control modes of CAVs are designed according to the upper-level decision made by the HPQ algorithm. Moreover, the vehicle control execution is realized by the model predictive controller combined with the geographical environment constraints and the unsignalized intersection management strategy. The proposed strategy is evaluated by simulations, which show that the proposed intersection management strategy can effectively reduce travel time and improve traffic efficiency. Results show that the proposed method can decrease the average travel time by 5% to 65% for different traffic flows compared with the comparative methods. The intersection management strategy captures the real-world balance between efficiency and safety for future intelligent traffic systems. Copyright © 2022, The Authors. All rights reserved.

关键词： Travel time

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