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A new method for evaluating wedges of steel plates and strips

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Journal of Iron and Steel Research International 2024年第7期31卷 1719-1735页

作者： Xiao-bao Ma Xiao-xin Ma Tao Wang Zhong-kai ren Yu-cheng ren College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Ministry of Education Engineering Research Center of Advanced Metal Composite Forming Technology and Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina China National Heavy Machinery Research Institute Co. Ltd.Xi'an 710018ShaanxiChina Faculty of Mechanical Engineering Hebei University of ArchitectureZhangjiakou 075000HebeiChina

To overcome the inaccuracy problem of the traditional wedge evaluation of steel plates and strips caused by the ran-domness of the thicknesses of two local points and improve the reliability of the wedge index,the double-centroid method for the wedge evaluation was proposed,and a model based on the centroid theory was ***,an integral model for the discrete thickness values of the cross-section profiles was *** discussion focused on the distinct characteristics of the two-point method,asymmetric method,and double-centroid method in evaluating the asymmetric distribution of *** three methods were employed to evaluate the wedge values of both the theoretical and measured cross-sections of steel plates and strips,and the accuracies of three wedge evaluation models were analyzed and *** results showed that the double-centroid method objectively reflects the degree and variation characteristics of the wedge values of the cross-sections of steel plates and strips,and this method is feasible,reliable,and outstanding.

关键词： Steel plate and strip Wedge Two-point method Double-centroid method Reliability

A Feature Selection Method Based on Hybrid Dung Beetle Optimization Algorithm and Slap Swarm Algorithm

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Computers, Materials & Continua 2024年第8期80卷 2979-3000页

作者： Wei Liu Tengteng ren School of Information Science and Engineering Shenyang Ligong UniversityShenyang110158China

Feature Selection(FS)is a key pre-processing step in pattern recognition and data mining tasks,which can effectively avoid the impact of irrelevant and redundant features on the performance of classification *** recent years,meta-heuristic algorithms have been widely used in FS problems,so a Hybrid Binary Chaotic Salp Swarm Dung Beetle Optimization(HBCSSDBO)algorithm is proposed in this paper to improve the effect of *** this hybrid algorithm,the original continuous optimization algorithm is converted into binary form by the S-type transfer function and applied to the FS *** combining the K nearest neighbor(KNN)classifier,the comparative experiments for FS are carried out between the proposed method and four advanced meta-heuristic algorithms on 16 UCI(University of California,Irvine)*** evaluation metrics such as average adaptation,average prediction accuracy,and average running time are chosen to judge and compare the *** selected dataset is also discussed by categorizing it into three dimensions:high,medium,and low *** results show that the HBCSSDBO feature selection method has the ability to obtain a good subset of features while maintaining high classification accuracy,shows better optimization *** addition,the results of statistical tests confirm the significant validity of the method.

关键词： Feature selection dung beetle optimization KNN transfer function HBCSSDBO

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考虑恢复依赖的基础设施网络应急恢复决策

中国管理科学 2022年第1期30卷 154-164页

作者：任爱俊冯耕中田军西安交通大学管理学院陕西西安710049

在大规模突发事件发生后,基础设施恢复任务之间会形成复杂的依赖关系,本文考虑了在此条件下基础设施系统的恢复设计与调度决策问题。基于网络流理论,以累积恢复效能最大化与成本最小化为目标,构建了涵盖阻塞依赖、选项依赖和效率依赖三... 详细信息

在大规模突发事件发生后,基础设施恢复任务之间会形成复杂的依赖关系,本文考虑了在此条件下基础设施系统的恢复设计与调度决策问题。基于网络流理论,以累积恢复效能最大化与成本最小化为目标,构建了涵盖阻塞依赖、选项依赖和效率依赖三类恢复依赖关系的集成恢复设计与调度决策混合整数规划模型,并且设计了求解模型的启发式算法。最后,以长沙市真实基础设施数据集为基础,构造了突发事件后的损毁场景实例,利用模型求解得出了受损基础设施的恢复设计与调度决策方案,并且分析了决策周期长度与工作组数量对累积恢复效能和成本的影响。结果表明:(1)该模型在突发事件后的基础设施恢复决策中具有应用可行性;(2)决策周期长度显著影响累积恢复效能,随着决策周期长度与恢复过程中各组件恢复耗时契合度的提升,累积恢复效能获得有效增长,并且,在决策周期长度的取值范围内,总成本存在最小值;(3)随工作组数量的增加,累积恢复效能呈增长趋势,增长率逐渐减小,同时,总成本呈减少趋势,减少率也逐渐减小。

关键词：基础设施网络流恢复依赖恢复效能决策

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污泥活性炭的制备、结构表征及吸附特性

哈尔滨工业大学学报 2007年第6期39卷 993-996页

作者：任爱玲王启山郭斌南开大学环境科学与工程学院天津300070 河北科技大学环境科学与工程学院石家庄050018

以城市污水厂污泥为原料,氯化锌为制孔剂,加入适当添加剂制备污泥活性炭,借助吸附等温线和BET、FT-IR、SEM等现代分析测试方法,表征其结构和吸附特性.结果表明：活化温度600℃、活化时间30 min、ZnCl2浓度50%、原料粒度20-24目时制备的... 详细信息

以城市污水厂污泥为原料,氯化锌为制孔剂,加入适当添加剂制备污泥活性炭,借助吸附等温线和BET、FT-IR、SEM等现代分析测试方法,表征其结构和吸附特性.结果表明：活化温度600℃、活化时间30 min、ZnCl2浓度50%、原料粒度20-24目时制备的污泥活性炭,其碘吸附值为643.0-815.6 mg/g,最可几孔径分布在4.16 nm左右,具有介空结构;平均孔容为0.4484-0.5122 mL/g,比表面积为634.8-748 m^2/g,IR峰中C＝C、C-H、N＝O、C-OH是活性炭表面功能组.污泥活性炭对苯酚的吸附以多层吸附和毛细孔凝聚为主,微孔填满后达饱和,24 h饱和吸附量为15 mg/g.

关键词：污水污泥活性炭结构表征吸附特性

Event-triggered H_(∞) consensus control for input-constrained multi-agent systems via reinforcement learning

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Control Theory and Technology 2024年第1期22卷 25-38页

作者： Jinxuan Zhang Chang-E ren College of Information Engineering Capital Normal UniversityBeijing100089China

This article presents an event-triggered H_(∞) consensus control scheme using reinforcement learning (RL) for nonlinear second-order multi-agent systems (MASs) with control constraints. First, considering control constraints, the constrained H_(∞) consensus problem is transformed into a multi-player zero-sum game with non-quadratic performance functions. Then, an event-triggered control method is presented to conserve communication resources and a new triggering condition is developed for each agent to make the triggering threshold independent of the disturbance attenuation level. To derive the optimal controller that can minimize the cost function in the case of worst disturbance, a constrained Hamilton–Jacobi–Bellman (HJB) equation is defined. Since it is difficult to solve analytically due to its strongly non-linearity, reinforcement learning (RL) is implemented to obtain the optimal controller. In specific, the optimal performance function and the worst-case disturbance are approximated by a time-triggered critic network;meanwhile, the optimal controller is approximated by event-triggered actor network. After that, Lyapunov analysis is utilized to prove the uniformly ultimately bounded (UUB) stability of the system and that the network weight errors are UUB. Finally, a simulation example is utilized to demonstrate the effectiveness of the control strategy provided.

关键词： H_(∞)optimal control Input constrains Multi-agent systems(MASs) Reinforcement learning(RL)

COVID-19疫情在我国的空间特征及影响因素分析

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安全与环境学报 2022年第2期22卷 892-900页

作者：段在鹏艾仁华福州大学环境与安全工程学院福州350108

探究了新型冠状病毒肺炎(COVID-19)在我国传播中的空间特性,并深入分析了各类因素对其传播的影响。首先基于全国COVID-19累计确诊数据计算Moran指数,验证了疫情传播具有空间集聚性。通过LISA图确定集聚区域:四川为HL,湖北、湖南、江西... 详细信息

探究了新型冠状病毒肺炎(COVID-19)在我国传播中的空间特性,并深入分析了各类因素对其传播的影响。首先基于全国COVID-19累计确诊数据计算Moran指数,验证了疫情传播具有空间集聚性。通过LISA图确定集聚区域:四川为HL,湖北、湖南、江西、安徽、重庆和河南为HH,新疆和青海为LL。之后充分考虑地缘因素,在普通最小二乘(OLS)、空间滞后(SLM)和空间误差(SEM)3个模型中,优选出空间误差回归模型分析本次疫情传播的影响因素。回归结果显示,在人口、经济、医疗和迁徙4大方面中,共8个因素在95%置信区间显著影响了确诊人数。其中正影响因素有4个,负影响因素有4个。根据SEM模型结果,为了尽快控制疫情传播,应大力推行医疗保险,更加严格地对出入境货物进行检验检疫。同时不鼓励居民在疫情期间进行消费,不鼓励普通本专科学生开学,进一步减少人口的流动性。需着重注意:因为此次疫情情况较为特殊,“分地区普通本专科学生情况”和“医疗卫生与计划生育支出”2个因素产生了与普遍研究结果相反的影响。

关键词：公共安全新型冠状病毒空间自相关空间集聚性空间误差回归模型

Polyelectrolyte Complexes and Coacervates Formed by De novo-Designed Peptides and Oligonucleotide

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Chinese Journal of Polymer Science 2024年第9期42卷 1333-1340,I0007页

作者： Tian-Hao ren De-Hai Liang Beijing National Laboratory for Molecular Sciences Department of Polymer Science and Engineering and the Key Laboratory of Polymer Chemistry and Physics of the Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China

The liquid-liquid phase separation of biopolymers in living cells contains multiple interactions and occurs in a dynamic *** the regulation mechanism is still a *** this work,we designed a series of peptides(XXLY)_(6)SSSGSS and studied their complexation and coacervation behavior with single-stranded ***“X”and“Y”are varied to combine known amounts of charged and non-charged amino acids,together with the introduction of secondary structures and pH *** show that the electrostatic interaction,which is described as charge density,controls both the strength of complexation and the degree of chain relaxation,and thus determines the growth and size of the *** hydrophobic interaction is prominent when the charges are ***,the secondary structures of peptides exhibit profound effect on the morphology of the phases,such as solid phase to liquid phase *** study gains insight into the phase separation under physiological *** is also helpful to create coacervates with desirable structures and functions.

关键词： Polyelectrolyte complex Coacervate Peptides Secondary structure Electrostatic interaction

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计算机仿真技术应用于奥运场馆火灾安全分析

自然灾害学报 2005年第4期14卷 95-102页

作者：史健勇任爱珠清华大学土木工程系北京100084

以奥运场馆旧馆改造项目为背景,利用计算机技术,采用性能化防火分析手段,建立了对奥运场馆进行性能化防火分析的软件系统。该系统采用数值模拟的方法,将火灾场景模拟与结构分析综合为一体,完成了性能化防火分析思想的软件实现,利用该系... 详细信息

以奥运场馆旧馆改造项目为背景,利用计算机技术,采用性能化防火分析手段,建立了对奥运场馆进行性能化防火分析的软件系统。该系统采用数值模拟的方法,将火灾场景模拟与结构分析综合为一体,完成了性能化防火分析思想的软件实现,利用该系统模拟了被指定为北京奥运会比赛用馆的某已建体育馆在设定火灾下的火灾场景和结构温度场分布,并对该场馆的火灾安全提出了进一步分析的建议,通过分析结果可以得到网架结构的最危险区域的温度。实例分析表明,该系统功能强大,运行方便,充分体现了计算机仿真技术在建筑防火分析中的优越性。

关键词：火灾模拟计算机模拟软件系统防火安全奥运会

Finite-size-induced non-Hermitian phase transitions in real space

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 105-111页

作者： Hongfei Wang Biye Xie Wei ren Department of Physics International Center for Quantum and Molecular StructuresShanghai UniversityShanghai 200444China School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China

While non-Hermiticity provokes intriguing phenomena without Hermitian counterparts, e.g., the skin effect and the breakdown of bulk-boundary correspondence, attracting extensive attention both in fundamental physics and device engineering, the role of finite sizes therein remains elusive. Here, we propose a class of finite-size-induced non-Hermitian phase transitions, relying upon higher-order topological invariants associated with real-space wave functions. The phase diagrams for general non-Hermitian chiral models are further acquired to demonstrate our topological definition. Such phase transitions are elucidated qualitatively by an effective intercell coupling alteration that depends on finite sizes in respective directions. Besides, we mimic these phenomena by analogizing the circuit Laplacian in finite-size electric circuits with nonreciprocal couplings. The resultant admittance spectra agree with our theoretical predictions. Our findings shed light on the finite-size mechanism of non-Hermitian topological phase transitions and pave the way for applications in switching and sensing.

关键词： non-Hermitian phase transitions finite-size effects higher-order topological invariants