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V2X环境下基于MPC算法的弯道区域CACC车队轨迹跟踪控制策略

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控制与决策 2024年第3期39卷 975-984页

作者：赵红专吴浩卢宁宁付建胜许恩永展新何水龙桂林电子科技大学广西智慧交通重点实验室广西桂林541004 桂林电子科技大学建筑与交通工程学院广西桂林541004 东风柳州汽车有限公司商用车技术中心广西柳州545005 桂林电子科技大学机电工程学院广西桂林541004

针对CACC (cooperative adaptive cruise control)车队在弯道行驶的安全性和稳定性问题,提出一种V2X (vehicle to everything)环境下基于MPC (model predictive control)算法的弯道区域CACC车队行驶轨迹跟踪策略.首先,分析CACC车队在弯道区域的行驶工况以及纵向平衡问题,并基于牛顿第二定律构建车辆在弯道行驶的车辆动力学模型;其次, CACC车队基于V2X技术实现车车之间状态信息的实时交互,并以基于车辆运动学的MPC算法为基础,引入可变间距的车队安全距离控制模型,提出一种适用于弯道区域的轨迹跟踪模型;最后,通过二次规划进行模型求解.实验分析结果表明:V2X环境下的CACC车队在弯道行驶过程中面对不同的行驶工况能够不同程度地保证车车之间的安全性、稳定性以及驾乘人员的舒适性,有效验证了所提V2X环境下基于MPC算法的弯道区域CACC车队轨迹跟踪策略的可行性.

关键词：弯道区域 CACC车队轨迹跟踪 MPC 可变间距二次规划

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涡轮电推进系统建模及控制规律设计

推进技术 2024年第1期45卷 18-30页

作者：江天牧张晓博王占学刘永泉姚尧郝旺西北工业大学动力与能源学院陕西西安710129

为了研究涡轮电推进系统的工作特性及控制规律设计方法,建立了涡轮电推进系统总体性能仿真模型。基于部件法建立了涵道风扇性能计算模型;基于电机效率图建立了发电机及电动机性能计算模型;基于面向对象的建模方法建立了电推进模块计算... 详细信息

为了研究涡轮电推进系统的工作特性及控制规律设计方法,建立了涡轮电推进系统总体性能仿真模型。基于部件法建立了涵道风扇性能计算模型;基于电机效率图建立了发电机及电动机性能计算模型;基于面向对象的建模方法建立了电推进模块计算模型。将建立的电推进模块计算模型加入涡扇发动机部件级仿真模型中,构建了涡轮电推进系统的共同工作方程组,即其性能仿真模型。采用逆算法研究了不同几何参数控制规律下,涵道风扇推力调节时推进系统的工作特性。通过在性能仿真模型中添加推力平衡方程,并结合差分进化算法构建涡轮电推进系统优化模型,形成了涡轮电推进系统控制规律优化设计方法,应用此方法计算了推进系统节流过程控制规律和性能参数。计算结果表明:本模型设计点性能计算结果与国外发动机性能计算软件计算结果最大偏差仅为0.22%,验证了建模方法的有效性;当涵道风扇推力改变时,可能导致涡扇发动机出现超温、超转和喘振等问题,通过联合调节尾喷管喉部面积和涵道引射器面积,可以有效改善这些问题;设计出的节流过程控制规律可以保证不超温、不超转,具有足够的喘振裕度,且在节流过程中还能进一步降低耗油率;该控制规律还具有连续、单调的特点,利于工程实现。

关键词：航空发动机涡轮电推进系统推进系统建模差分进化算法控制规律设计

Mechanical and Barrier Properties of Epoxy/ultra-short Glass Fibers Composite Coatings

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Journal of Materials Science & Technology 2012年第12期28卷 1077-1084页

作者： Yongsheng hao Fuchun Liu en-Hou Han State Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences Shenyang110016 China

Epoxy coatings containing different volume fractions of ultra-short glass fibers were prepared successfully. Ultra-short glass fiber not only can improve the hardness, adhesion of the coating, and glass transition tem-perature （Tg）, but also can decrease the coefficient of thermal expansion （CTE） of the coating. Electrochemical impedance spectroscopy （EIS） was used to evaluate the barrier properties of the coatings containing different volume fractions of ultra-short glass fibers. The EIS results showed that the coating had the best barrier property when it contained 20% （volume fraction） ultra-short glass fibers. The functions of the ultra-short glass fibers in epoxy coating are two fold： first, they can improve the coating mechanical properties as reinforcement materials; second, they parallel to the substrate and inhibit the corrosive medium to pass through the coating.

关键词： Glass fiber Barrier Electrochemical impedance spectroscopy Thermal expansion

Research on the knee region of cosmic ray by using a novel type of electron-neutron detector array

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Frontiers of physics 2024年第4期19卷 13-24页

作者： Bing-Bing Li Xin-Hua Ma Shu-wang Cui hao-Kun Chen Tian-Lu Chen Danzengluobu Wei Gao Hai-Bing Hu Denis Kuleshov Kirill Kurinov Hu Liu Mao-Yuan Liu Ye Liu Da-Yu Peng Yao-Hui Qi Oleg Shchegolev Yuri Stenkin Li-Qiao Yin Heng-Yu Zhang Liang-Wei Zhang College of Physics Hebei Normal UniversityShijiazhuang 050024China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China TIANFU Cosmic Ray Research Center Chengdu 610000China College of Science Tibet UniversityLhasa 850000China Key Laboratory of Comic Rays Ministry of EducationTibet UniversityLhasa 850000China Institute for Nuclear Research of the Russian Academy of Sciences Moscow 117312Russia School of Physical Science and Technology Southwest Jiaotong UniversityChengdu 610031China School of Management Science and engineering Hebei University of Economics and BusinessShijiazhuang 050061China Moscow Institute of Physics and Technology Moscow 141700Russia

By accurately measuring composition and energy spectrum of cosmic ray,the origin problem of so called“knee”region(energy>one PeV)can be ***,up to the present,the results of the spectrum in the knee region obtained by several previous experiments have shown obvious differences,so they cannot give effective evidence for judging the theoretical models on the origin of the ***,the Large High Altitude Air Shower Observatory(LHAASO)has reported several major breakthroughs and important results in astro-particle physics *** on its advantages of wide-sky survey,high altitude location and large area detector arrays,the research content of LHAASO experiment mainly includes ultra high-energy gamma-ray astronomy,measurement of cosmic ray spectra in the knee region,searching for dark matter and new phenomena of particle physics at higher *** electron and thermal neutron detector(en-Detector)is a new scintillator detector which applies thermal neutron detection technology to measure cosmic ray extensive air shower(EAS).This technology is an extension of *** en-Detector Array(enDA)can highly efficiently measure thermal neutrons generated by secondary hadrons so called“skeleton”of *** this paper,we perform the optimization of enDA configuration,and obtain expectations on the enDA results,including thermal neutron distribution,trigger efficiency and capability of cosmic ray composition *** obtained real data results are consistent with those by the Monte Carlo simulation.

关键词： cosmic ray EAS knee region LHAASO enDA

维普期刊数据库评论

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煤矿工种知识图谱智能问答研究

计算机技术与发展 2024年第3期34卷 185-192页

作者：刘鹏程浩然王莹魏微丁恩杰矿山物联网应用技术国家地方联合工程实验室江苏徐州221008 中国矿业大学物联网(感知矿山)研究中心江苏徐州221008 中国矿业大学信息与控制工程学院江苏徐州221116

知识图谱是用于表征实体间结构关系的新一代知识库,其通过语义网络描述现实世界事物之间的逻辑关系,而基于知识图谱的智能问答技术也在不断发展,智能问答系统与知识图谱相结合,是对结构化知识的进一步剖析及利用。该文通过收集煤矿工种... 详细信息

知识图谱是用于表征实体间结构关系的新一代知识库,其通过语义网络描述现实世界事物之间的逻辑关系,而基于知识图谱的智能问答技术也在不断发展,智能问答系统与知识图谱相结合,是对结构化知识的进一步剖析及利用。该文通过收集煤矿工种专业信息,构建煤矿工种知识图谱,并在此基础上对智能问答技术和系统进行了研究。在知识图谱构建方面,对工种专业进行定义,通过Bert-BiLSTM-CRF实体识别模型对煤矿工种关键信息进行抽取,再利用图数据库存储三元组工种知识数据得到工种图谱。在智能问答环节,通过设计问题模板,利用Bert模型实现端到端的问句意图识别和槽位提取,并采用Sentente-Bert对问句的提及词和知识图谱的候选实体进行链接,继而将问句转化形成图数据库查询语句,从图谱中返回答案。实验结果表明,构建的煤矿工种知识图谱及智能问答系统,在多个评价指标表现良好,可以满足煤矿工种知识问答需求,为煤矿智能化建设做出了有益探索。

关键词：煤矿工种知识图谱智能问答意图识别槽位提取

中药材种植中植物生长调节剂的使用现状和应对措施

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中国新药杂志 2024年第14期33卷 1429-1436页

作者：安晓静刘尚年郭皓李先恩王彦婷关敏郭宝林陈彩霞中国医学科学院北京协和医学院药用植物研究所/中草药物质基础与资源利用教育部重点实验室/濒危药材繁育国家工程实验室北京100193 天津中医药大学中药学院天津301617 成都中医药大学药学院西南特色中药资源国家重点实验室成都611137 河北农业大学农学院保定071000

植物生长调节剂(plant growth regulator,PGR)是一类具有植物激素活性的人工合成的化合物,能通过调控植物生长发育、形态建成及物质代谢等,提高中药材产量和抗逆性。随着中药材种植品种和面积的增加,PGR在中药材种植生产中应用愈加广泛... 详细信息

植物生长调节剂(plant growth regulator,PGR)是一类具有植物激素活性的人工合成的化合物,能通过调控植物生长发育、形态建成及物质代谢等,提高中药材产量和抗逆性。随着中药材种植品种和面积的增加,PGR在中药材种植生产中应用愈加广泛。由于种植户对PGR缺乏充分认识和科学系统了解,使用时存在为追求产量盲目增加PGR种类和用量,导致药材品质下降等盲目乱用现象。本文通过对中药材主产区PGR使用现状进行调研,并结合近年来相关研究的文献资料,对中药材生产中PGR应用现状进行归纳、总结,分析中药材生产中PGR存在的问题,并提出可行建议和应对措施,以期为中药材生产实践中PGR应用提供技术指导和理论依据。

关键词：中药材植物生长调节剂使用现状应对措施

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柴油机喷孔夹角对燃烧过程的影响

内燃机与动力装置 2016年第4期33卷 24-28页

作者：张盼盼郑清平王恩浩黎明刘晓日河北工业大学能源与环境工程学院天津300401 驻三五六厂军代室云南昆明650114

本文建立了某四缸增压直喷柴油机的三维模型,研究喷孔夹角α对燃烧过程的影响,分别选取α=140°、α=150°和α=160°三种喷孔夹角模拟计算。研究结果表明:喷孔夹角α对燃油的空间分布影响很大。喷孔夹角α=140°时,过多燃油进入燃烧室... 详细信息

本文建立了某四缸增压直喷柴油机的三维模型,研究喷孔夹角α对燃烧过程的影响,分别选取α=140°、α=150°和α=160°三种喷孔夹角模拟计算。研究结果表明:喷孔夹角α对燃油的空间分布影响很大。喷孔夹角α=140°时,过多燃油进入燃烧室底部,略微提升动力性的同时造成NOx和Soot的排放升高;喷孔夹角α=160°时,会造成大量燃油进入余隙容积,动力性下降,NOx和Soot的减少。综合考虑各种因素,本文选取的最佳喷孔夹角α=150°。

关键词：柴油机喷孔夹角燃油分布 NOx Soot

Creep characteristics and constitutive model for frozen mixed soils

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Journal of Mountain Science 2021年第7期18卷 1966-1976页

作者： SONG Bing-tang LIU en-long SHI Zhao-yun wang Pan YU Qi-hao Northwest Institute of Eco-environment and Resources State Key Laboratory of Frozen Soil EngineeringChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Hydraulics and Mountain River engineering College of Water Resources and HydropowerSichuan UniversityChengdu 610065China Yalong River Hydropower Development Company Ltd. Chengdu 610051China

The uniform settle caused by the permafrost creep is still the primary problem of engineering construction in cold *** investigate the creep characteristics of frozen soils mixed with silty clay and coarse-grained sand,several triaxial creep tests of frozen mixed soils under different conditions(temperature,confining pressure,coarse-grained particle content) were performed,and the effects of the temperature,confining pressure and coarse particle content on the creep characteristics of frozen mixed soils were also *** results of the experiments indicated that when the confining pressure was low,the specimen exhibited an attenuation creep under a low-stress level(0.4-0.7) and a non-attenuation creep under a high-stress level(0.7-0.9).In contrast,when the confining pressure was high,the specimen had both initial and stable creep stages,but no the accelerated creep *** higher the content of coarse grains,the shorter the stable creep stage,and the easier to enter the accelerated creep stage for the ***,the long-term strength of frozen soils decreased with an increase in the content of coarse ***,a newly improved Nishihara model was proposed to consider both the hardening effect and damage effect by introducing both the hardening and damage variables,which can model the entire creep process of frozen soils modeled relatively *** was found that with the increasing content of coarse particle,both the strengthening and damaged effects in the creep process are reduced。

关键词： Frozen mixed soil Creep Hardening and damage Constitutive model

Spatiotemporal regulation of ubiquitin-mediated protein degradation via upconversion optogenetic nanosystem

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Nano Research 2020年第12期13卷 3253-3260页

作者： Yafeng hao Taofeng Du Gaoju Pang Jiahua Li Huizhuo Pan Yingying Zhang Lizhen wang Jin Chang en-min Zhou Hanjie wang School of Life Sciences Tianjin UniversityTianjin300072China Department of preventive Veterinary Medicine College of Veterinary MedicineNorthwest A&F UniversityYangling712100China

Protein degradation technology,which is one of the most direct and effective ways to regulate the life activities of cells,is expected to be applied to the treatment of various ***,current protein degradation technologies such as some small-molecule degraders which are unable to achieve spatiotemporal regulation,making them difficult to transform into clinical *** this article,an upconversion optogenetic nanosystem was designed to attain accurate regulation of protein *** system worked via two interconnected parts:1)the host cell expressed light-sensitive protein that could trigger the ubiquitinproteasome pathway upon blue-light exposure;2)the light regulated light-sensitive protein by changing light conditions to achieve regulation of protein *** results based on model protein(Green Fluorescent Protein,GFP)validated that this system could fulfill protein degradation both in vitro(both Hela and 293T cells)and in vivo(by upconversion optogenetic nanosystem),and further demonstrated that we could reach spatiotemporal regulation by changing the illumination time(0–25 h)and the illumination frequency(the illuminating frequency of 0–30 s every 1 min).We further took another functional protein(The Nonstructural Protein 9,NSP9)into *** confirmed that the proliferation of porcine reproductive and respiratory syndrome virus(PRRSV)was inhibited by degrading the NSP9 in this light-induced system,and PRRSV proliferation was affected by different light conditions(illumination time varies from 0–24 h).We expected this system could provide new perspectives into spatiotemporal regulation of protein degradation and help realize the clinical application transformation for treating diseases of protein degradation technology.

关键词： protein degradation ubiquitin-proteasome system optogenetics upconversion materials the nonstructural protein9(NSP9) porcine reproductive and respiratory syndrome virus(PRRSV)