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不可避撞场景下的车辆碰撞损伤最小化策略

浙江大学学报(工学版) 2025年第2期59卷 362-374页

作者：叶身村周兵柴天干年妃贺帅湖南大学汽车车身先进设计制造国家重点实验室湖南长沙410082 舍弗勒智能驾驶科技(长沙)有限公司湖南长沙410036

针对不可避撞场景下如何有效地减小车辆碰撞损伤并保证响应的高实时性,提出采用决策层和运动控制层分层结构的碰撞损伤最小化策略.考虑在车辆动力学约束的情况下通过求解最优控制问题生成离线轨迹库,通过四自由度碰撞模型和碰撞前的车... 详细信息

针对不可避撞场景下如何有效地减小车辆碰撞损伤并保证响应的高实时性,提出采用决策层和运动控制层分层结构的碰撞损伤最小化策略.考虑在车辆动力学约束的情况下通过求解最优控制问题生成离线轨迹库,通过四自由度碰撞模型和碰撞前的车辆状态来估计碰后自车失稳风险,通过碰撞损伤评估模型在线评估轨迹库中轨迹的碰撞时风险和碰后自车失稳风险,在决策时以极短时间从轨迹库中确定出最优轨迹.在运动控制层,为了保持轨迹跟踪精度和车辆稳定性,基于模型预测控制建立轨迹跟踪与横摆稳定性协同控制器.在不同场景下进行仿真,验证所提出的碰撞损伤最小化策略的有效性.仿真结果表明,所提出的碰撞损伤最小化策略能够在保证不同工况下车辆稳定性的同时,有效地减小车辆碰撞损伤.

关键词：不可避撞碰撞损伤四自由度碰撞模型轨迹跟踪横摆稳定性

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基于有限体积法的中子扩散和输运算法开发

核技术 2025年第1期48卷 162-175页

作者：李卫刘晓晶柴翔赵鹏程南华大学资源环境与安全工程学院衡阳421001 上海交通大学机械与动力工程学院上海200240 上海市数值反应堆技术融合创新中心上海200240 南华大学核科学技术学院衡阳421001

随着核热耦合技术的发展,为了考虑多物理场之间的强耦合效应,实现高精度和大规模并行计算,有必要对多物理场守恒方程联立求解,统一处理建模、离散和迭代计算过程。本文基于开源计算流体力学(Computational Fluid Dynamics,CFD)平台OpenF... 详细信息

随着核热耦合技术的发展,为了考虑多物理场之间的强耦合效应,实现高精度和大规模并行计算,有必要对多物理场守恒方程联立求解,统一处理建模、离散和迭代计算过程。本文基于开源计算流体力学(Computational Fluid Dynamics,CFD)平台OpenFOAM,使用有限体积法(Finite Volume Method,FVM)和高斯定理,对中子扩散和中子输运的控制方程进行离散,实现了对多群中子扩散方程和中子输运方程离散和迭代求解。中子输运方程的离散中使用离散纵标法对空间角度进行离散。为了验证开发程序的有效性,验证计算中采用包括国际原子能机构(International Atomic Energy Agency,IAEA)、TAKEDA和C5G7等在内的多个基准算例对开发的中子扩散和输运程序进行验证。通过对包括非均匀化堆芯基准问题在内的不同基准题中稳态和瞬态结果进行对比验证。验证结果表明:基于有限体积法可以同时实现对均匀化和非均匀化中子物理问题的精确求解,并且具有几何适应性强的特点。为未来实现统一编程框架下的物理与热工多物理场守恒方程的联立求解奠定了基础。

关键词：有限体积法中子扩散方程中子输运方程 OpenFOAM

Microstructure and martensitic transformation behavior of Ni_(56-x)Mn_(25)Fe_xGa_(19) shape memory alloys

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Rare Metals 2014年第1期33卷 41-46页

作者： Yan Xin Liang chai School of Energy Power and Mechanical Engineering North China Electric Power University Beijing Key Laboratory for Advanced Functional Materials and Thin Film Technology

Microstructure, martensitic transformation behavior, mechanical and shape memory properties of ***25FexGa19 （x = 0, 2, 4, 6, 8） shape memory alloys were investigated using optical microscopy （OM）, X-ray diffraction analysis （XRD）, differential scanning calorimeter （DSC）, and compressive test. It is found that these alloys are composed of single non-modulated martensite phase with tetragonal structure at room temperature, which means substituting Fe for Ni in Ni56Mn25Ga19 alloy has no effect on phase structure. These alloys all exhibit a ther- moelastic martensitic transformation between the cubic parent phase and the tetragonal martensite phase. With the increase of Fe content, the martensitic transformation peak temperature （Mp） decreases from 356℃ for x = 0 to 20℃ for x = 8, which is contributed to the depressed electron concentration and tetragonality of martensite. Fe addition remarkably reduces the transformation hysteresis of Ni-Mn-Ga alloys. Substituting Fe for Ni in Ni56Mn25Ga19 alloy can decrease the strength of the alloys and almost has no influence on the ductility and shape memory property.

关键词： Shape memory alloys Microstructure Martensitic transformation Ni-Mn-Fe-Ga

Optimal Load Balancing Leveling Method for Multi-leg Flexible Platforms

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Chinese Journal of Mechanical Engineering 2013年第5期26卷 900-908页

作者： GANG Xianyue chai Shan School of Transportation and Vehicle Engineering Shandong University of Technology

The working platforms supported with multiple extensible legs must be leveled before they come into *** the supporting stiffness and reliability of the platform are improved with the increasing number of the supporting legs,the increased overdetermination of the multi-leg platform systems leads to leveling coupling problem among legs and virtual leg problem in which some of the supporting legs bear zero or quasi zero *** problems make it quite complex and time consuming to level such a multi-leg *** on rigid body kinematics,an approximate equation is formulated to rapidly calculate the leg extension for leveling a rigid platform,then a proportional speed control strategy is proposed to reduce the unexpected platform distortion and leveling coupling between supporting *** both the load coupling between supporting legs and the elastic flexibility of the working platform into consideration,an optimal balancing legs’ loads(OBLL) model is firstly put forward to deal with the traditional virtual leg *** taking advantage of the concept of supporting stiffness matrix,a coupling extension method(CEM) is developed to solve this OBLL problem for multi-leg flexible *** the end,with the concept of supporting stiffness matrix and static transmissibility matrix,an optimal load balancing leveling method is proposed to achieve geometric leveling and legs’ loads balancing *** numerical examples are given out to illustrate the performance of proposed *** paper proposes a method which can effectively quantify all of the legs’ extension at the same time,achieve geometric leveling and legs’ loads balancing *** using the proposed methods,the stability,precision and efficiency of auto-leveling control process can be improved.

关键词： multi-leg platform overdetermined problem optimal balancing legs' loads supporting stiffness matrix static transmissibility matrix

LightGCNet:基于轻量化卷积网络的深度色域压缩算法

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计算机科学与探索 2025年第1期19卷 196-210页

作者：杨晨徐昊朱佳伟吴秦柴志雷江南大学人工智能与计算机学院江苏无锡214122 江苏省模式识别与计算智能工程实验室江苏无锡214122

色域压缩是大色域向小色域进行转换时保持色彩信息的关键技术。经典算法虽计算快速,但处理结果缺乏细节且没有考虑人眼的感知特性,难以满足人们对色彩品质不断提升的要求。迭代算法处理效果更佳,但极其耗时,无法投入实际应用。针对上述... 详细信息

色域压缩是大色域向小色域进行转换时保持色彩信息的关键技术。经典算法虽计算快速,但处理结果缺乏细节且没有考虑人眼的感知特性,难以满足人们对色彩品质不断提升的要求。迭代算法处理效果更佳,但极其耗时,无法投入实际应用。针对上述问题,提出了轻量化的深度色域压缩方法,该方法可在逼近迭代算法计算效果的同时保持接近经典算法的速度。为色域压缩算法设计了LightGCNet模型,该网络中的双层卷积由DSC与DW卷积组合而成,相比常规U-Net,参数量与计算复杂度急剧降低。为进一步提高模型先验性,将预训练得到的DW卷积中多个核通道进行重聚焦操作以建立联系,最终权重由重聚焦权重和预训练权重组成。针对色相、明度、彩度这三个色彩属性,设计了色域压缩专用的损失函数。该函数不仅考虑了像素级损失,而且融合了图像感知损失,并联合色彩属性的多尺度信息进行加权,解决了深度色域压缩过程中细节丢失的问题。基于迭代算法生成标签以训练网络,联合学习目标色域特征与图像信息,实现了与迭代算法相当的效果。实验结果表明:该方法与业界经典的SGCK算法相比,iCID值降低了17.08%,SSIM值提高了5.30%。相比常规U-Net模型,LightGCNet参数量减少了82.96%,乘加次数从8.5GFLOPs大幅下降至2.2GFLOPs,使改良模型更适于低端设备部署。该模型在CPU上处理单幅512×512图像仅需0.208s,计算时间比迭代类算法减少99.92%。

关键词：色域压缩轻量化深度学习色彩管理

Regularity for Euler-Bernoulli Equations with Boundary Control and Collocated Observation

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Journal of Systems Science & Complexity 2015年第4期28卷 788-798页

作者： WEN Ruili chai Shugen School of Mathematical Sciences Shanxi University

This paper studies the regularity of Euler-Bernoulli equations on a bounded domain of Rn(n≥2)with boundary controls and collocated *** authors consider the Dirichlet controls in the case of hinged and clamped boundary controls *** is shown that the systems are regular in the sense of *** feedthrough operators are founded to be zero.

关键词： Boundary control and collocated observation Euler-Bernoulli plate equation regularity.

STATE FEEDBACK STABILIZATION FOR A CLASS OF NONLINEAR TIME-DELAY SYSTEMS VIA DYNAMIC LINEAR CONTROLLERS

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Journal of Systems Science & Complexity 2014年第3期27卷 453-462页

作者： chai Lin QIAN Chunjiang School of Automation Southeast University Key Laboratory of Measurement and Control of Complex Systems of Engineering Southeast University Department of Electrical and Computer Engineering University of Texas at San AntonioSan AntonioTX 78249USA

The dynamic linear state feedback control problem is addressed for a class of nonlinear systems subject to ***,using the dynamic change of coordinates,the problem of global state feedback stabilization is solved for a class of time-delay systems under a type of nonhomogeneous growth *** the aid of an appropriate Lyapunov-Krasovskii functional and the adaptive strategy used in coordinates,the closed-loop system can be globally asymptotically stabilized by the dynamic linear state feedback *** growth condition in perturbations are more general than that in the existing *** correctness of the theoretical results are illustrated with an academic simulation example.

关键词： Dynamic linear controller global stabilization nonlinear time-delay systems state feed-back control.

Bullous pemphigoid associated with acquired hemophilia A: A case report

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World Journal of Clinical Cases 2025年第4期13卷 28-33页

作者： Su-Ye Hu Meng-Can Li Zi-Jia Hao Xu-Ya chai Pei-Sai Li Yang Liu Li-Xia Liu Ying Xu Pan-Pan Yang Ling-E Li Department of Dermatology Shijiazhuang Traditional Chinese Medicine HospitalShijiazhuang 050051Hebei ProvinceChina Graduate School Hebei University of Traditional Chinese MedicineShijiazhuang 050051Hebei ProvinceChina Department of Pathology Shijiazhuang Traditional Chinese Medicine HospitalShijiazhuang 050051Hebei ProvinceChina

BACKGROUND Acquired hemophilia A (AHA) is a rare and potentially severe bleeding disordercaused by circulating autoantibodies against factor Ⅷ (FⅧ). In approximately50% of the patients, the condition is associated with autoimmune diseases,cancers, medication use, pregnancy, and the post-partum period. Bullous pemphigoid(BP) is a chronic autoimmune subepidermal blistering disease associatedwith tissue-bound and circulating autoantibodies against BP antigens 180 (BP180)and 230 (BP230). AHA-associated BP has a high mortality rate;hence, the understandingof this disease must *** SUMMARY A 69-year-old man presented with erythema, blisters, blood blisters, and crustsaccompanied by severe pruritus for more than 20 days, and ecchymosis andswelling on his left upper arm for 3 days. Pathological examination revealed asubepidermal blister that contained eosinophils. Laboratory tests showed that theBP180 autoantibody levels had increased, isolated activated partial thromboplastintime was notably prolonged (115.6 s), and coagulation FⅧ activity wasextremely low (< 1.0%). Furthermore, the FⅧ inhibitor titer had greatlyincreased (59.2 Bethesda units). Therefore, the patient was diagnosed as having BP associated with AHA, prescribed 0.05% topical halometasone cream, and transferred to a higher-level hospitalfor effective treatment;however, he died after 2 *** AHA associated BP is rare, dangerous, and has a high mortality rate. Therefore, its timely diagnosis and effectivetreatment are necessary.

关键词： Bullous pemphigoid Acquired hemophilia A Acquired hemophilia A FactorⅧ Case report

The Stability of Schrdinger Equation with Boundary Control Matched Disturbance

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Journal of Systems Science & Complexity 2017年第6期30卷 1258-1269页

作者： ZHANG Xiaoying chai Shugen School of Mathematical Sciences Shanxi University Department of Mathematics Shanxi Agriculture University

This paper studies the stability of Schr¨odinger equation with boundary control matched disturbance. The time-varying gain extended state observer is utilized to estimate disturbance and state. Meanwhile, the authors get a continuous controller by the active disturbance rejection control strategy, which shows that the closed-loop system of Schr¨odinger equation is asymptotically *** results are illustrated by simulation examples.

关键词： Active disturbance rejection control extended state observer SchrSdinger equation stability.