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Experimental study on the interrelation of multiple mechanical parameters in overburden rock caving process during coal mining in longwall panel

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International Journal of Coal Science & Technology 2023年第4期10卷 265-289页

作者： Daixin Deng hongwei wang Lili Xie Zeliang wang Jiaqi Song School of Mechanics and Civil Engineering China University of Mining and TechnologyBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyBeijing 100083China

In order to comprehend the dynamic disaster mechanism induced by overburden rock caving during the advancement of a coal mining face, a physical simulation model is constructed basing on the geological condition of the 21221 mining face at Qianqiu coal mine in Henan Province, China. This study established, a comprehensive monitoring system to investigate the interrelations and evolutionary characteristics among multiple mechanical parameters, including mining-induced stress, displacement, temperature, and acoustic emission events during overburden rock caving. It is suggested that, despite the uniformity of the overburden rock caving interval, the main characteristic of overburden rock lies in its uneven caving strength. The mining-induced stress exhibits a reasonable interrelation with the displacement, temperature, and acoustic emission events of the rock strata. With the advancement of the coal seam, the mining-induced stress undergoes four successive stages: gentle stability, gradual accumulation, high-level mutation, and a return to stability. The variations in other mechanical parameters does not synchronize with the signifcant changes in mining-induced stress. Before the collapse of overburden rock occurs, rock strata temperature increment decreases and the acoustic emission ringing counts surges with the increase of rock strata displacement and mining-induced stress. Therefore, the collaborative characteristics of mining-induced stress, displacement, temperature, and acoustic emission ringing counts can be identifed as the precursor information or overburden rock caving. These results are in good consistent with on-site situation in the coal mine.

关键词： Overburden rock caving Multiple mechanical parameters Interrelation characterization Precursor information

Attitude control of flapping wing aircraft based on energy optimization and ESO

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Biomimetic Intelligence & Robotics 2021年第1期1卷 36-41页

作者： Luo Li hongwei wang Long Cui State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China

Aiming at the problem of insufficient endurance performance of flapping wing aircraft,a stable attitude control algorithm based on energy optimization and ESO(extended state observer)is designed,which effectively reduces the energy consumption in cruise ***,the longitudinal dynamic model of flapping wing aircraft is established,and then the uncertain part of the system and various unknown external disturbances are taken as the total *** module is introduced to observe and track the total disturbance in real ***,the system is transformed into a series integral system through the total disturbance feedback,and then the energy optimal control law is designed on the base of the transformed *** numerical simulation results show that,compared with the traditional PID control method,the designed energy optimal control method reduces the average energy consumption by 35.28%.

关键词： Flapping wing Energy optimal control ESO(Extended State Observer)

New approach for the digital reconstruction of complex mine faults and its application in mining

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International Journal of Coal Science & Technology 2022年第3期9卷 91-105页

作者： hongwei wang Zeliang wang Yaodong Jiang Jiaqi Song Meina Jia School of Mechanics and Civil Engineering China University of Mining and Technology-BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology-BeijingBeijing 100083China

Visualization of complex geological structures can technically support the accurate prediction and prevention of coal mine *** study proposed a new digital reconstruction method to visualize geological structures based on establishing a virtual model in the digital twin *** methodology for the digital reconstruction of complex fault structures comprises the following four aspects:(1)collection and fdelity of multi-physical feld data of the fault structures,(2)the transmission of multi-physical feld data,(3)the normalization of multi-physical feld data,and(4)digital model reconstruction of fault *** key scientifc issues of this methodology to be resolved include in situ fdelity of multi-feld data and normalized programming of multi-source *** addition,according to the geological background and conditions in Da’anshan coal mine in western Beijing,China,a preliminary attempt is made to reconstruct a digital model of fault and fold structures using the methodology proposed in this study.

关键词： Digital reconstruction Fault structure Multi-physical feld Data collection and fdelity

Servitization in Construction and its Transformation Pathway: A Value-Adding Perspective

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Engineering 2022年第12期19卷 166-179页

作者： Dian Liu hongwei wang Botao Zhong Lieyun Ding SILC Business School Shanghai UniversityShanghai 201899China School of Management Huazhong University of Science and TechnologyWuhan 430074China School of Civil and Hydraulic Engineering Huazhong University of Science and TechnologyWuhan 430074China

Against the current social and technological background dominated by services and technology,new opportunities are opening up for the industrial transformation and upgrading of the construction *** the successful transformation and upgrading of the manufacturing industry through servitization,scholars and practitioners have begun to explore the possibility of servitization in the construction *** practices and theory show that different understandings of servitization in the construction sector exist;however,they are still in their infancy and lack a deep and systematic awareness,which does not benefit the transformation and upgrading of construction through ***,this paper systematically analyzes the motivation,definition,and implications of servitization in construction based on the value-adding nature of servitization and considers the problems confronting the construction *** facilitate this development,transformation pathways for servitization in construction are analyzed from multiple angles,including value co-creation,service innovation,and networked operation,which are in line with the new trends in digital *** addition,based on the supporting elements of construction,which include finance,human resources,technology,materials,and equipment,this paper examines the impact of servitization on the construction industry’s *** short,we expect that this systematic analysis and exposition can provide a holistic view of servitization in construction from the inside out for scholars and practitioners and can help to promote servitization in construction.

关键词： Servitization in construction Value-adding Service innovation Platform sharing

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蛋白质组学技术及其在氟中毒研究中的应用

黑龙江畜牧兽医 2024年第10期 27-31,39页

作者：赵源杨琳于亚明田维顺王宏伟赵静河南科技大学动物科技学院河南洛阳471023

氟在自然界中广泛存在,是机体必需微量元素之一。摄入少量氟对机体骨骼及牙齿有保护作用,但长期过量摄入氟会造成机体慢性氟中毒,对机体造成骨相及非骨相损伤,严重威胁着动物的健康。随着蛋白质组学技术的发展及其在氟中毒研究中的应用... 详细信息

氟在自然界中广泛存在,是机体必需微量元素之一。摄入少量氟对机体骨骼及牙齿有保护作用,但长期过量摄入氟会造成机体慢性氟中毒,对机体造成骨相及非骨相损伤,严重威胁着动物的健康。随着蛋白质组学技术的发展及其在氟中毒研究中的应用,人们对氟的骨相及非骨相毒性的分子机制研究越来越深入。笔者主要介绍了包括质谱分析、双向电泳、高效液相色谱分析、免疫共沉淀、同位素标记相对和绝对定量及蛋白质芯片等蛋白质组学技术的原理及特点,并概述了这些蛋白质组学技术在氟的骨相和非骨相毒性研究中的应用,旨在为进一步探究氟中毒的致病机制提供思路和见解。

关键词：蛋白质组学氟中毒骨相非骨相分子机制

Synergy effect of multi-strengthening mechanisms in FeMnCoCrN HEA at cryogenic temperature

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Journal of Materials Science & Technology 2021年第27期86卷 158-170页

作者： Zhufeng He Nan Jia hongwei wang Haile Yan Yongfeng Shen Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Material Science and EngineeringNortheastern UniversityShenyang 110819China State Key Lab Rolling&Automat Northeastern UniversityShenyang 110819China

High-entropy alloys(HEAs)have attracted great research interest owing to their good combination of high strength and ductility at both room and cryogenic ***,expensive raw materials are always added to overcome the strength-ductility trade-off at low temperatures,leading to an increased production cost for the cryogenically used *** this work,a series of nitrogen-doped Fe Mn Co Cr HEAs have been processed by homogenization annealing,cold rolling and recrystallization annealing followed by water *** microstructural evolution and mechanical properties of the alloys are studied *** Fe_(49)Mn_(30)Co_(10)Cr_(10)N1alloy shows excellent mechanical properties at both 293 K and 77 ***,the yield and ultimate tensile strength of 1078 and 1630 MPa are achieved at the cryogenic temperature,respectively,while a satisfactory uniform elongation of 33.5%is *** ultrahigh yield strength results from the microstructure refinement caused by the activation of athermal martensitic transformation and mechanical twinning that occur in the elastic regime together with the increased lattice friction due to the cryogenic *** the plastic regime,the dynamic Hall-Petch effect caused by twinning,martensitic transformation,and reverse transformation together with the high barrier to dislocation motion jointly contribute to the ultrahigh tensile ***,the transformation induced plasticity(TRIP)and the twinning induced plasticity(TWIP)effects jointly contribute to the *** design strategy for attaining superior mechanical properties at low temperatures,*** adjusting stacking fault energy in the interstitial metastable HEAs,guides the development of high-performance and low-cost alloys for cryogenic applications.

关键词： High-entropy alloy Cryogenic deformation Nitrogen doping Phase transformation Twinning

1.4003不锈钢与Q345NQR2耐候钢电阻点焊接头的组织和疲劳性能

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焊接技术 2024年第3期53卷 46-49页

作者：王羽王红伟梁涛闫国瑞宋睿中车唐山机车车辆有限公司河北唐山063000 大连交通大学材料科学与工程学院辽宁大连116028

通过金相组织分析、硬度试验、脉动拉伸疲劳试验及疲劳断口形貌分析,研究了1.5 mm 1.4003+3 mm Q345NQR2电阻点焊接头的组织和疲劳性能。结果表明:Q345NQR2钢母材组织为白色铁素体+层片状珠光体,1.4003铁素体不锈钢母材组织为多边形或... 详细信息

通过金相组织分析、硬度试验、脉动拉伸疲劳试验及疲劳断口形貌分析,研究了1.5 mm 1.4003+3 mm Q345NQR2电阻点焊接头的组织和疲劳性能。结果表明:Q345NQR2钢母材组织为白色铁素体+层片状珠光体,1.4003铁素体不锈钢母材组织为多边形或无规则型铁素体,Q345NQR2侧HAZ分为正火细晶区和过热粗晶区,正火细晶区珠光体较细小,过热粗晶区珠光体较粗大,1.4003铁素体不锈钢侧HAZ为单一块状的多边形铁素体,晶粒度4~5级,熔核区显微组织为少量珠光体、贝氏体、板条马氏体与极少量残余奥氏体混合组织。熔核区硬度值在425HV~505HV之间,明显高于母材及熔合线处硬度。疲劳断口位于熔核区,其接头指定寿命为1×10~7次循环下的中值疲劳强度,2.875 kN。

关键词： 1.4003铁素体不锈钢 Q345NQR2耐候钢金相组织疲劳性能

Ternary red phosphorus/CoP2/SiO2 microsphere boosts visible-light-driven photocatalytic hydrogen evolution from pure water splitting

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Journal of Materials Science & Technology 2022年第30期125卷 59-66页

作者： Chen Yang Yukun Zhu Yiming Liu hongwei wang Dongjiang Yang School of Environmental Science and Engineering State Key Laboratory of Bio-fibers and Eco-textilesShandong Collaborative Innovation Center of Marine Biobased Fibers and Ecological TextilesQingdao UniversityQingdao 266071China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

Red phosphorus(RP) is a promising visible-light-driven semiconductor for photocatalytic hydrogen evolution,but the activity is restricted due to the rapid charge carrier recombination and sluggish surface reaction ***,cobalt phosphide(CoP_(2)) modified RP heterostructure was developed by in situ phosphorization of cobalt oxide from phosphorus *** tuning the amounts of CoP_(2) in the heterostructure,the optimized hybrid exhibited a HER rate reaching 11.79 μmol h^(-1) under visible light illumination,which is 3.5 times higher than that of the RP with Pt as *** was experimentally indicated that the intimate interaction between CoP_(2) and RP gave rise to improved visible light absorption and accelerated photogenerated electron-holes ***,the CoP_(2) as a noble-metal-free cocatalyst could promote the surface hydrogen evolution reaction,which synergetic benefited the photocatalytic hydrogen production activity.

关键词： Red phosphorus Cobalt phosphide Heterostructure Photocatalytic hydrogen evolution

A model predictive control strategy with switching cost functions for cooperative operation of trains

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Science China(Information Sciences) 2023年第7期66卷 224-236页

作者： Zixuan ZHANG Haifeng SONG hongwei wang Ling LIU Hairong DONG State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University School of Electronic and Information Engineering Beihang University Beijing National Railway Research and Design Institute of Signal and Communication

The cooperative control of trains is proposed as an innovative method for further improving operation efficiency. Model predictive control(MPC) has been widely discussed for multiple trains because it can handle the challenges posed by the cooperative control problem, such as complex constraints. In real situations, multiple objectives, such as comfort and safety, must be considered when controlling multiple trains with MPC, and the total objective may change during operation, affecting control performance. In this paper, a distributed structure based on switching cost function model predictive control(ScMPC) for multiple trains in a switching situation is given, where the cost functions of the train control problem change with the variable demand of cooperative operation. Furthermore, the feasibility of the proposed method and stability of the closed-loop system are proved to guarantee the stable operation of the controlled ***, the control method’s effectiveness is verified. Three kinds of cost functions are given, and their control performance is compared to show the effect of different weights and the advantage of ScMPC.

关键词： cooperative control switching cost functions model predictive control automatic train operation railway train

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