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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 101-114页

作者： Minghao Cao Jilai Yu the Department of electrical engineering Harbin Institute of TechnologyHarbinChina

With the increasing proportion of renewable energy sources(RESs)in power grid,the reserve resource(RR)scarcity for correcting power deviation of RESs has become a potential ***,the power curve of RES needs to be more rigorously *** RR scarcity varies during different time periods,so the values of assessment indicators should be dynamically *** assessment indicators in this paper include two aspects,i.e.,deviation exemption ratio and penalty ***,this paper proposes a method for dynamically calculating the supply capacity and RR cost,primarily taking into account the operating status of thermal units,forecast information of RES,and load ***,after clarifying the logical relationship between the degree of RR scarcity and the values of assessment indicators,this paper establishes a mapping function between *** on this mapping function,a dynamic setting method for assessment indicators is *** the future,RES will generally be equipped with battery energy storage systems(BESSs).Reasonably utilizing BESSs to reduce the power deviation of RESs can increase the expected income of ***,this paper proposes a power curve optimization strategy for RESs considering self-owned *** case study demonstrates that the dynamic setting method of assessment indicators can increase the revenue of RESs while ensuring that the penalty fees paid by RESs to the grid are sufficient to cover the RR ***,the power curve optimization strategy can help RESs further increase income and fully utilize BESSs to reduce power deviation.

关键词： Renewable energy battery energy storage system(BESS) power curve assessment reserve service parameter setting

Realization of nonreciprocal acoustic energy transfer using an asymmetric strong nonlinear vibroacoustic system

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International Journal of mechanical System Dynamics 2024年第1期4卷 99-114页

作者： Jiangming Jin Jingxiao Huang Yuepeng Xiao Sound and Vibration Laboratory College of Mechanical EngineeringZhejiang University of TechnologyHangzhouChina

In this paper,an asymmetric vibroacoustic system that can passively realize nonreciprocal transmission of acoustic energy is *** experimental system consists of a waveguide,a strongly nonlinear membrane,and three acoustic cavities with different *** theoretical modeling of the system is verified by experiments,and parametric analysis is also carried *** intensive studies reveal the nonreciprocal transmission of acoustic energy in this prototype *** forward excitation,internal resonance between the two nonlinear normal modes of the vibroacoustic system occurs,and acoustic energy is irreversibly transferred from the waveguide to the nonlinear ***,under backward excitation,there is no internal resonance in the *** spectra and wavelet analysis are used to highlight the mechanism of nonreciprocal transfer of acoustic ***,nearly unidirectional(preferential)transmission of acoustic energy transfer is shown by this *** nonreciprocal acoustic energy transfer method illustrated in this paper provides a new way to design the odd acoustic element.

关键词： vibroacoustic system acoustic nonreciprocity nonlinear normal mode transient resonance capture

A new method for evaluating the firing precision of multiple launch rocket system based on Bayesian theory

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Defence Technology（防务技术） 2024年第2期32卷 232-241页

作者： Yunfei Miao Guoping Wang Wei Tian College of mechanical and electrical engineering Nanjing University of Aeronautics and AstronauticsNanjingJiangsuChina institute of Launch Dynamics Nanjing University of Science and TechnologyNanjingJiangsuChina

How to effectively evaluate the firing precision of weapon equipment at low cost is one of the core contents of improving the test level of weapon system.A new method to evaluate the firing precision of the MLRS considering the credibility of simulation system based on Bayesian theory is proposed in this *** of all,a comprehensive index system for the credibility of the simulation system of the firing precision of the MLRS is constructed combined with the group analytic hierarchy process.A modified method for determining the comprehensive weight of the index is established to improve the rationality of the index weight *** Bayesian posterior estimation formula of firing precision considering prior information is derived in the form of mixed prior distribution,and the rationality of prior information used in estimation model is discussed *** the simulation tests,the different evaluation methods are compared to validate the effectiveness of the proposed ***,the experimental results show that the effectiveness of estimation method for firing precision is improved by more than 25%.

关键词： Multiple launch rocket system Bayesian theory Simulation credibility Mixed prior distribution Firing precision

Near resonance vibration isolation on a levered-dual response(LEDAR)Coulomb-damped system by differential preloads/offsets in linear springs

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1033-1050页

作者： T.I.TOLUWALOJU C.K.THEIN D.HALIM Department of mechanical Materials and Manufacturing EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100Zhejiang ProvinceChina Nottingham Ningbo China Beacons of Excellence Research and Innovation institute University of Nottingham Ningbo ChinaNingbo 315048Zhejiang ProvinceChina

The levered-dual response(LEDAR)Coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear *** takes the advantages of both the preloads/offsets in linear springs and the guiderail friction for realizing different levels of vibration *** isolation capacities are investigated on the strategies with both the horizontal and vertical guiderails,with the horizontal rail only,and without *** compressive preloads generally result in the consumption of most of the initial excitation energy so as to overcome the potential *** isolation onsets at the frequency ratio of 1∓0.095 on the left-hand side(LHS)and the right-hand side(RHS)of the lever are relative to the load plate *** observed near resonant isolation thus makes the LEDAR system a candidate for the isolation of the mechanical systems about resonance while opening a path for simultaneous harvesterisolation functions and passive functions at extreme frequencies.

关键词： lever ratio Coulomb damping preload tension/compression isolation band/depth offset potential

Urban Traffic Control Meets Decision Recommendation System:A Survey and Perspective

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IEEE/CAA Journal of Automatica Sinica 2024年第10期11卷 2043-2058页

作者： Qingyuan Ji Xiaoyue Wen Junchen Jin Yongdong Zhu Yisheng Lv zhejiang Lab Hangzhou 311121China College of engineering and Architecture Zhejiang UniversityHangzhou 310013China College of electrical engineering Zhejiang UniversityHangzhou 310013China the State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China IEEE

Urban traffic control is a multifaceted and demanding task that necessitates extensive decision-making to ensure the safety and efficiency of urban transportation *** approaches require traffic signal professionals to manually intervene on traffic control devices at the intersection level,utilizing their knowledge and ***,this process is cumbersome,labor-intensive,and cannot be applied on a large network *** studies have begun to explore the applicability of recommendation system for urban traffic control,which offer increased control efficiency and *** a decision recommendation system is complex,with various interdependent components,but a systematic literature review has not yet been *** this work,we present an up-to-date survey that elucidates all the detailed components of a recommendation system for urban traffic control,demonstrates the utility and efficacy of such a system in the real world using data and knowledgedriven approaches,and discusses the current challenges and potential future directions of this field.

关键词： Recommendation system traffic control traffic perception traffic prediction

3D printed grafts with gradient structures for organized vascular regeneration

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International Journal of Extreme Manufacturing 2024年第3期6卷 505-520页

作者： Yuewei Chen Zhongfei Zou Tao Fu Zhuang Li Zhaojie Zhang Meng Zhu Qing Gao Shaofei Wu Guosheng Fu Yong He Jiayin Fu State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China School of mechanical engineering Guizhou UniversityGuiyang 550025People’s Republic of China Key Laboratory of Cardiovascular Intervention and Regenerative Medicine of zhejiang Province Department of CardiologySir Run Run Shaw HospitalZhejiang UniversityHangzhou 310016People’s Republic of China School of mechanical engineering Guizhou Institute of TechnologyGuiyang 550003People’s Republic of China Department of Oral and Maxillofacial Surgery The Second Affiliated Hospital of Zhejiang University School of MedicineSchool of Stomatologyand Key Laboratory of Oral Biomedical Research of Zhejiang ProvinceHangzhouZhejiang 310006People’s Republic of China

Synthetic vascular grafts suitable for small-diameter arteries(<6 mm) are in great ***,there are still no commercially available small-diameter vascular grafts(SDVGs) in clinical practice due to thrombosis and stenosi... 详细信息

Synthetic vascular grafts suitable for small-diameter arteries(mechanical properties mimicking natural *** by the collagen alignment of SML,the inner layer of the grafts had larger pore sizes and high porosity to accelerate the infiltration of cells and their circumferential alignment,which could facilitate SML reconstruction for compliance restoration and spontaneous *** outer layer was designed to induce fibroblast recruitment by low porosity and minor pore size and provide SDVG with sufficient mechanical *** month after implantation,the arteries regenerated by 3D-printed grafts exhibited better pulsatility than electrospun grafts,with a compliance(8.9%) approaching that of natural arteries(11.36%) and significantly higher than that of electrospun ones(1.9%).The 3D-printed vascular demonstrated a three-layer structure more closely resembling natural arteries while electrospun grafts showed incomplete endothelium and immature *** study shows the importance of SML reconstruction during vascular graft regeneration and provides an effective strategy to reconstruct blood vessels through 3D-printed structures rapidly.

关键词： small-diameter vascular graft smooth muscle layer 3D printing endothelialization

A Dual-Task Learning Approach for Bearing Anomaly Detection and State Evaluation of Safe Region

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Chinese Journal of mechanical engineering 2024年第1期37卷 229-241页

作者： Yuhua Yin Zhiliang Liu Bin Guo Mingjian Zuo School of mechanical and electrical engineering University of Electronic Science and Technology of ChinaChengdu 611731China Qingdao International Academician Park Research institute Qingdao 266041China

Predictive maintenance has emerged as an effective tool for curbing maintenance costs,yet prevailing research predominantly concentrates on the abnormal *** the ostensibly stable healthy phase,the reliance on anomaly detection to preempt equipment malfunctions faces the challenge of sudden anomaly *** address this challenge,this paper proposes a dual-task learning approach for bearing anomaly detection and state evaluation of safe *** proposed method transforms the execution of the two tasks into an optimization issue of the hypersphere *** leveraging the monotonicity and distinguishability pertinent to the tasks as the foundation for optimization,it reconstructs the SVDD model to ensure equilibrium in the model’s performance across the two *** experiments verify the proposed method’s effectiveness,which is interpreted from the perspectives of parameter adjustment and enveloping *** the meantime,experimental results also show two deficiencies in anomaly detection accuracy and state evaluation *** theoretical analysis inspires us to focus on feature extraction and data collection to achieve *** proposed method lays the foundation for realizing predictive maintenance in a healthy stage by improving condition awareness in safe regions.

关键词： Bearing condition monitoring Anomaly detection Safe region Support vector data description

Effect of the vortical structures on the hydrodynamic performance of a pitching hydrofoil

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Journal of Hydrodynamics 2024年第2期36卷 406-420页

作者： Rui Yuan Hui-yun Hao Qin Wu Yun-qing Liu Biao Huang School of mechanical engineering Beijing Institute of TechnologyBeijing100081China

The objective is to study the vortical structural behaviors of a transient pitching hydrofoil and their effects on the hydrodynamic performance. The pitching motion of the hydrofoil is set to pitch up with an almost constant rate from 5° to 15° and then back to 5°, with the Reynolds number 4.4×10^(5) and the frequency 2 Hz. The results show that the main coherent structures around the pitching hydrofoil include small-scale laminar separation bubble (LSB), large-scale second vortex (SV) and trailing edge vortex (TEV) which are all vortical. The relationship between the vortical structure and the lift is investigated with the finite-domain impulse theory. It indicates that the major part of the lift is contributed by the LSB, whereas the shedding and the formation of the SV and TEV cause the fluctuation of the lift. The proper orthogonal decomposition (POD) method is applied to capture the most energetic modes, revealing that the LSB mode occupies a large amount of energy in the flow field. The dynamic mode decomposition (DMD) method accurately extracts the dominant frequency and modal characteristics, with the first mode corresponding to the mean flow, the second mode corresponding to the LSB structure and the third and fourth modes corresponding to the vortex shedding.

关键词： Hydrodynamics vortical structures finite-domain impulse theory proper orthogonal decomposition(POD) dynamic mode decomposition(DMD) Pitching hydrofoil

A novel predictive braking energy recovery strategy for electric vehicles considering motor thermal protection

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Science China(Technological Sciences) 2024年第4期67卷 1253-1269页

作者： YANG Chao SUN TongLin YANG LiuQuan ZHANG YuHang WANG WeiDa School of mechanical engineering Beijing Institute of TechnologyBeijing 100084China

Braking energy recovery(BER)aims to recover the vehicle's kinetic energy by coordinating the motor and mechanical braking torque to extend the driving range of the electric vehicle(EV).To achieve this goal,the motor/generator mode requires frequent switching and prolonged operation during *** this case,the motor temperature will unavoidably rise,potentially triggering motor thermal protection(MTP).Activating MTP increases the risk of motor component failure,and the EV typically disables the BER ***,maximizing BER while reducing the risk of motor overheating is a challenging *** address this issue,this article proposes a predictive BER strategy with MTP using the non-smooth Pontryagin Minimum Principle(NSPMP)for ***,a Markov long short-term memory(MLSTM)model is designed to obtain future velocity ***,the BER problem with MTP in the studied EV is embedded in a model predictive control(MPC)***,under the MPC framework,the NSPMP strategy is proposed to resolve the problem of ***,the performance of the proposed strategy is verified through simulation and a hardware-in-loop *** results show that in two real-world driving cycles,compared to the rule-based strategy,the proposed strategy reduced power consumption by 1.24%and0.96%,respectively,and effectively limited motor ***,under global cycle conditions,this strategy demonstrated better MTP control performance compared to other benchmark strategies.

关键词： electric vehicle braking energy recovery strategy motor thermal protection non-smooth PMP

Influence of ambient temperature on the CO_(2)emitted of light-duty vehicle

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Journal of Environmental Sciences 2024年第6期140卷 59-68页

作者： Dan Tan Yachao Wang Jianwei Tan Jiachen Li Changyu Wang Yunshan Ge School of mechanical engineering Beijing Institute of TechnologyBeijing 100081China

Because of global warming,people have paid more attention to greenhouse gas emitted by *** quantify the impact of temperature on vehicle CO_(2)emissions,this study was conducted using the world light vehicle test cycle on two light-duty E10 gasoline vehicles a ambient temperatures of-10,0,23,and 40℃,and found that CO_(2)emission factors of Vehicle1 in the low-speed phase were 22.07%and 20.22%higher than those of Vehicle 2 at cold star and hot start under-10℃.The reason was vehicle 1 had a larger displacement and more friction pairs than vehicle *** was the highest CO_(2)emission at the low-speed phase due to low average speed,frequent acceleration,and *** CO_(2)temperature factor and the ambient temperature had a strong linear correlation(R2=0.99).According to CO_(2)temperature factors and their relationships,CO_(2)emission factors of other ambien temperatures could be calculated when the CO_(2)emission factor of 23℃was obtained,and the method also could be used to obtain the CO_(2)temperature factors of different *** separate the effect of load setting and temperature variation on CO_(2)emission quantitatively a method was *** results showed that the load setting was dominant for the CO_(2)emission *** with 23℃,the CO_(2)emission for vehicle 1 caused by load setting variation were 62.83 and 47.42 g/km,respectively at-10 and 0℃,while those fo vehicle 2 were 45.01 and 35.63 g/km,respectively.

关键词： CO_(2)emission Ambient temperature E10 gasoline Light-duty vehicle WLTC