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交通场景下的大型车辆右转停车检测方法研究

计算机工程与应用 2025年第1期61卷 352-360页

作者：王依凡董振江陈向东南京邮电大学计算机学院南京210023

随着大型车辆右转必停的新交规逐步实施,针对现有的监管方式存在效率较低的问题,提出了一种大型车辆右转停车检测方法。对YOLOv7-tiny检测模型进行改进,在ELAN模块中引入注意力机制,以提升大型车辆的检测性能。设计了一种新的大型车辆... 详细信息

随着大型车辆右转必停的新交规逐步实施,针对现有的监管方式存在效率较低的问题,提出了一种大型车辆右转停车检测方法。对YOLOv7-tiny检测模型进行改进,在ELAN模块中引入注意力机制,以提升大型车辆的检测性能。设计了一种新的大型车辆右转车道定位方法,通过自适应探测车道,提高了其在不同监控视角下的定位准确性。对大型车辆的运动轨迹进行序列数据转换,并采用结合加权平均的中值滤波算法,有效降低了原始数据的噪声。在滑动窗口损失函数中引入权重因子,进一步提升了检测方法的鲁棒性。实验结果表明,改进后的大型车辆检测模型在自制数据集和公开数据集上均取得了性能提升,大型车辆右转车道定位方法具有更强的泛化能力,并且检测到的停车时间覆盖率达到了97.4%。

关键词：大型车辆检测车道定位滤波算法损失函数停车时间检测

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大学生风险认知水平对其抑郁状态的影响

保山学院学报 2025年第1期44卷 103-108页

作者：王一帆保山学院教育学院云南保山678000

探究大学生风险认知水平对其抑郁状态的影响,以及心理资本在其中的保护作用。采用风险感知量表,压力-焦虑-抑郁量表和心理资本量表对5138名大学生进行调查,得出风险认知水平正向预测抑郁状态;心理资本中希望、效能、乐观维度均可负向预... 详细信息

探究大学生风险认知水平对其抑郁状态的影响,以及心理资本在其中的保护作用。采用风险感知量表,压力-焦虑-抑郁量表和心理资本量表对5138名大学生进行调查,得出风险认知水平正向预测抑郁状态;心理资本中希望、效能、乐观维度均可负向预测抑郁状态;心理资本的效能维度在风险认知与抑郁状态的关系中起调节作用,即风险认知对抑郁状态的预测力随效能的增加而降低。结论:大学生的抑郁症状呈现出较高的发生率,风险认知水平影响个体抑郁状态水平。心理资本中的效能维度在风险认知与抑郁状态关系中起调节作用,能有效降低风险认知对抑郁症状表现的消极影响。

关键词：大学生风险认知抑郁状态心理资本调节作用

Effect of beam current on microstructures and mechanical properties of joints of TZM/30CrMnSiA by electron beam welding

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Chinese Journal of Aeronautics 2021年第8期34卷 122-130页

作者： Ting wang Bin YU yifan wang Siyuan JIANG State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology at WeihaiWeihai 264209China Shandong Provincial Key Laboratory of Special Welding Technology Harbin Institute of Technology at WeihaiWeihai 264209China

Electron beam welding experiments of TZM alloy and 30CrMnSiA steel butt joints were carried out with different beam *** and chemical compositions of typical zones were analyzed by optical microscopy,scanning electron microscopy and X-ray *** mechanical properties of the joints were evaluated by tensile strength ***,nanoindentation tests were carried out to compare the brittleness of the reaction layer and other typical *** results illustrated that the reaction layer at the interface between fusion zone(FZ)and TZM alloy was the weak position of the joint,which was divided into Fe2Mo layer and a mixture layer of Fe2Mo and a-Fe *** the beam current increased,the thickness of the Fe2Mo layer decreased,which resulted in the increasing of the tensile strength of the *** the beam current exceeded 24 m A,the formation of the joint was poor with a low tensile *** the beam current was 24 mA,the joint presented the highest strength of 191.3 MPa and the joint fractured along the Fe2Mo layer near the TZM alloy side with a brittle fracture mode.

关键词： 30CrMnSiA Electron beam welding Mechanical properties Microstructure TZM alloy

Linear stability analysis of interactions between mixing layer and boundary layer flows

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Chinese Journal of Aeronautics 2017年第4期30卷 1327-1335页

作者： Fengjun LIU yifan wang Ying PIAO Science and Technology on Scramjet Laboratory Beijing Power Machinery Institute School of Aerospace Engineering Tsinghua University

The linear instabilities of incompressible confluent mixing layer and boundary layer were *** mixing layers include wake,shear layer and their *** mean velocity profile of confluent flow is taken as a superposition of a hyperbolic and exponential function to model a mixing layer and the Blasius similarity solution for a flat plate boundary *** stability equation of confluent flow was solved by using the global numerical *** unstable modes associated with both the mixing and boundary layers were *** are the boundary layer mode,mixing layer mode 1（nearly symmetrical mode）and mode 2（nearly anti-symmetrical mode）.The interactions between the mixing layer stability and the boundary layer stability were *** the mixing layer approaches the boundary layer,the neutral curves of the boundary layer mode move to the upper left,the resulting critical Reynolds number decreases,and the growth rate of the most unstable mode *** wall tends to stabilize the mixing layer modes at low *** addition,the mode switching behavior of the relative level of the spatial growth rate between the mixing layer mode 1 and mode 2 with the velocity ratio is found to occur at low frequency.

关键词： Boundary layer Flow instability Linear stability theory Shear layer Wake

Memetic algorithm for multi-mode resource-constrained project scheduling problems

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Journal of Systems Engineering and Electronics 2014年第4期25卷 609-617页

作者： Shixin Liu Di Chen yifan wang College of Information Science and Engineering Northeastern University

A memetic algorithm （MA） for a multi-mode resourceconstrained project scheduling problem （MRCPSP） is proposed. We use a new fitness function and two very effective local search procedures in the proposed MA. The fitness function makes use of a mechanism called ＂strategic oscillation＂ to make the search process have a higher probability to visit solutions around a ＂feasible boundary＂. One of the local search procedures aims at improving the lower bound of project makespan to be less than a known upper bound, and another aims at improving a solution of an MRCPSP instance accepting infeasible solutions based on the new fitness function in the search process. A detailed computational experiment is set up using instances from the problem instance library PSPLIB. Computational results show that the proposed MA is very competitive with the state-of-the-art algorithms. The MA obtains improved solutions for one instance of set J30.

关键词： project scheduling resource-constrained multi-mode,memetic algorithm (MA) local search procedure.

A New Method for Estimating Lithium‑Ion Battery State‑of‑Energy Based on Multi‑timescale Filter

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Automotive Innovation 2023年第4期6卷 611-621页

作者： Guangming Zhao Wei Xu yifan wang Road Traffic Safety Research Center of the Ministry of Public Security Beijing 100068China China Automotive Engineering Research Institute Co. LtdChongqing 401120China

Accurate estimation of the state-of-energy(SOE)in lithium-ion batteries is critical for optimal energy management and energy optimization in electric ***,the conventional recursive least squares(RLS)algorithm struggle to track changes in battery model parameters under dynamic *** address this,a multi-timescale estimator is proposed.A variable forgetting factor RLS approach is used to determine the model parameters at a macro timescale,and the H infinity filter is utilized to estimate the SOE at a micro *** proposed algorithm is verified and analyzed and shown to have accurate and robust identification of battery model ***,experiments under dynamic cycles demonstrate that the proposed algorithm has a high level of accuracy for SOE estimation.

关键词： Forgetting factor State-of-energy Multi-timescale Lithium-ion battery

Synergistic Pd/Cu-catalyzed regio-and stereoselective cascade Heck cyclization/borylation/cross-coupling

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Chinese Chemical Letters 2023年第12期34卷 166-171页

作者： yifan wang Yuanyuan Ping wangqing Kong The Institute for Advanced Studies(IAS) Wuhan University.Wuhan 430072China

A cooperative Pd/Cu-catalyzed three-component cross-coupling reaction of alkynes,B_(2)Pin_(2) and alkene-tethered aryl halides is *** reaction proceeds under mild conditions and shows broad sub-strate scope,providing a variety of heterocycles containing tetrasubstituted alkenylboronate moieties in synthetically useful yields with excellent chemoselectivity and *** transformation fea-tures the catalytic generation ofβ-borylalkenylcopper intermediates and their use in Pd-catalyzed Heck cyclization/*** enantioselective cascade cyclization/cross-coupling process has also been developed for the synthesis of enantiomerically enriched oxindole bearing a tetrasubstituted alkenyl-boronate moiety.

关键词： Palladium/copper catalysis Heck cyclization Alkene difunctionalization Cross-coupling Borylation

BAMBOO CANOPY:TOWARDS A LIGHT CONSTRUCTION OF BAMBOO

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Journal of Green Building 2020年第3期15卷 215-234页

作者： yifan wang Qing Chun School of Architecture Southeast UniversityNanjing210096China

Despite the abundance of highly sustainable bamboo,people tend to overlook its structural performance for construction *** paper therefore explores the potential of bamboo architecture to develop light-weight building systems and also to create an effect of *** by a team at the School of Architecture of Southeast University,Bamboo Canopy is an outdoor stage canopy in Anji,China,that pushes the boundaries of bamboo as a material for building woven gridshell *** work is designed as a long-lifespan bamboo structure,with the design team and locals participating in its *** on a public stage,Bamboo Canopy experiments with the combination of sustainable construction and local craftsmanship to produce a highly engaging architectural intervention that activates the existing *** its wing-like form,it invites visitors to join the performance scene-as they approach the shell,the structure reveals itself-with a 12.4-metre span and 6-metre roof overhang,the canopy covers more than 150 square metres with only 1.2 square metres touching the *** analysing the form,structure and details of this experimental project,this paper clarifies not only the potentiality but also the feasibilities in using bamboo for light construction.

关键词： modern bamboo structure light construction woven gridshell structure structural performance of bamboo

Ballistic performance of additive manufacturing 316l stainless steel projectiles based on topology optimization method

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Defence Technology（防务技术） 2024年第5期35卷 1-17页

作者： Hao Xue Tao wang Xinyu Cui yifan wang Guangyan Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

Material and structure made by additive manufacturing(AM)have received much attention lately due to their flexibility and ability to customize complex *** study first implements multiple objective topology optimization simulations based on a projectile perforation model,and a new topologic projectile is *** two types of 316L stainless steel projectiles(the solid and the topology)are printed in a selective laser melt(SLM)machine to evaluate the penetration performance of the projectiles by the ballistic *** experiment results show that the dimensionless specific kinetic energy value of topologic projectiles is higher than that of solid projectiles,indicating the better penetration ability of the topologic ***,microscopic studies(scanning electron microscope and X-ray micro-CT)are performed on the remaining projectiles to investigate the failure mechanism of the internal structure of the topologic *** explicit dynamics simulation was also performed,and the failure locations of the residual topologic projectiles were in good agreement with the experimental results,which can better guide the design of new projectiles combining AM and topology optimization in the future.

关键词： Additive manufacturing Topology optimization Ballistic performance Projectile design