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EA4T钢的高温动态软化模型及晶粒演化研究

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钢铁研究学报 2024年第5期36卷 650-659页

作者：张艳黄光杰何杰王艳阳汪开忠王民章重庆大学材料科学与工程学院重庆400044 马鞍山钢铁股份有限公司安徽马鞍山243000

为优化后续热加工工艺,研究EA4T钢的热变形行为及微观组织演变规律。利用热模拟机对EA4T钢进行了单道次等温恒应变速率热压缩实验,变形温度为850~1200℃,应变速率为0.01~10s^(-1),真应变为0.9。结果表明:EA4T钢在低应变速率下(850~1200... 详细信息

为优化后续热加工工艺,研究EA4T钢的热变形行为及微观组织演变规律。利用热模拟机对EA4T钢进行了单道次等温恒应变速率热压缩实验,变形温度为850~1200℃,应变速率为0.01~10s^(-1),真应变为0.9。结果表明:EA4T钢在低应变速率下(850~1200℃,0.01、0.1s^(-1))和高应变速率(950~1200℃,1s^(-1))、(1050~1200℃,10s^(-1))条件下变形后发生了动态再结晶。动态再结晶可以通过改变微观组织从而决定钢的力学性能。将参数Z与微观组织演变结合,构建了EA4T钢的高温动态软化模型,可调控EA4T钢在热变形过程中发生动态回复、不完全动态再结晶、动态再结晶和晶粒长大的行为。采用电子背散射技术(EBSD)、透射电子显微测试等材料表征技术,分析了EA4T钢在不同变形条件下的动态再结晶晶粒、马氏体束的宽度和板条宽度的多尺度组织特征,建立了马氏体束宽与动态再结晶晶粒和变形参数Z的关系模型。研究结果可为EA4T钢热加工工艺提供理论指导。

关键词： EA4T车轴钢动态软化模型微观组织动态再结晶

间充质干细胞及细胞外囊泡治疗肺纤维化的现状与未来

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中国组织工程研究 2024年第25期28卷 4079-4086页

作者：王艳阳刘婵余丽梅何志旭遵义医科大学附属医院贵州省细胞工程重点实验室贵州省遵义市563000 遵义医科大学组织损伤修复与再生医学省部共建协同创新中心贵州省遵义市563000 贵州省儿童医院遵义医科大学附属医院小儿内科贵州省遵义市563000

背景:尽管在临床上采取了一系列的治疗措施,肺纤维化的治疗仍然面临着挑战。在近年的研究中,间充质干细胞及其细胞外囊泡作为一种新兴的治疗策略引起了广泛关注,被认为可能是治疗肺纤维化的有希望的手段。目的:综述间充质干细胞及其细... 详细信息

背景:尽管在临床上采取了一系列的治疗措施,肺纤维化的治疗仍然面临着挑战。在近年的研究中,间充质干细胞及其细胞外囊泡作为一种新兴的治疗策略引起了广泛关注,被认为可能是治疗肺纤维化的有希望的手段。目的:综述间充质干细胞及其细胞外囊泡在肺纤维化治疗方面的应用,以期全面了解其治疗机制、疗效评估和面临的问题,为未来进一步研究和临床应用提供参考和指导。方法:中文检索词为“间充质干细胞”“间充质干细胞细胞外囊泡”“肺纤维化”;英文检索词为“mesenchymal stem cells”“mesenchymal stem cell extracellular vesicles”“pulmonary fibrosis”,检索中国知网和PubMed电子期刊数据库,通过人工阅读排除重复文献等,最终纳入112篇文献,重点对58篇中英文文献进行归纳总结。结果与结论:①间充质干细胞及其细胞外囊泡可以通过多种机制抑制纤维化过程,如调节炎症反应、抑制成纤维细胞增殖和促进受损组织修复,临床试验的初步结果也显示出一定的治疗效果,包括改善患者的肺功能和生活质量。②然而,间充质干细胞及其细胞外囊泡治疗肺纤维化仍面临一些挑战。在治疗过程中需要解决细胞迁移和组织内定位等问题,以其能够准确到达受损肺组织。另外,长期安全性问题也有待进一步研究改进。对于其转化医学发展,细胞采集、细胞分离、细胞培养、细胞收获和细胞鉴定等标准化程序还需要被细化。③尽管面临这些挑战,但通过科研工作者和医务人员的共同努力,这些问题有望得到逐步解决。未来,可以通过优化治疗方案和探索个体化治疗进一步提高治疗效果。同时,深入研究间充质干细胞及其细胞外囊泡的治疗机制,有望开发出更为高效和安全的治疗策略。

关键词：肺纤维化间充质干细胞细胞外囊泡综述

Study of Multi-objective Fuzzy Optimization for Path Planning

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Chinese Journal of Aeronautics 2012年第1期25卷 51-56页

作者： wang yanyang WEI Tietao QU Xiangju School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

During path planning, it is necessary to satisfy the requirements of multiple objectives. Multi-objective synthesis is based on the need of flight mission and subjectivity inclination of decision-maker. The decision-maker, however, has illegibility for under- standing the requirements of multiple objectives and the subjectivity inclination. It is important to develop a reasonable cost performance index for describing the illegibility of the decision-maker in multi-objective path planning. Based on Voronoi dia- gram method for the path planning, this paper studies the synthesis method of the multi-objective cost performance index. Ac- cording to the application of the cost performance index to the path planning based on Voronoi diagram method, this paper ana- lyzes the cost performance index which has been referred to at present. The analysis shows the insufficiency of the cost per- formance index at present, i.e., it is difficult to synthesize sub-objective flmctions because of the great disparity of the sub-objective fimctions. Thus, a new approach is developed to optimize the cost performance index with the multi-objective fuzzy optimization strategy, and an improved performance index is established, which could coordinate the weight conflict of the sub-objective functions. Finally, the experimental result shows the effectiveness of the proposed approach.

关键词： flight paths path planning cost performance index synthesis of multi-objective fuzzy inference Voronoi diagram

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基于高级运动模型轨迹预测的不确定性分析

武汉大学学报(工学版) 2024年第9期57卷 1287-1294页

作者：王珂王艳阳黄秋实廖凯凯邓修金胡勇西华大学汽车测控与安全四川省重点实验室西华大学流体及动力机械教育部重点实验室绵阳新华内燃机股份有限公司

为研究车辆模型不确定性与环境感知不确定性对车辆轨迹预测精度的影响，利用Matlab建立恒横摆率和恒速度(constant turn rate and velocity, CTRV)轨迹预测模型，结合不同工况下采集的全球定位系统（global positioning system,GPS）与... 详细信息

为研究车辆模型不确定性与环境感知不确定性对车辆轨迹预测精度的影响，利用Matlab建立恒横摆率和恒速度(constant turn rate and velocity, CTRV)轨迹预测模型，结合不同工况下采集的全球定位系统（global positioning system,GPS）与惯性传感器（inertial measurement unit,IMU）融合定位数据集，运用扩展卡尔曼滤波(extended Kalman filters, EKF)算法处理车辆模型的过程噪声与传感器的测量噪声。在此基础上进行仿真实验，分析不同行驶工况下车辆轨迹预测误差及对轨迹预测模型5个状态量的影响。结果表明：EKF算法能够很好地处理车辆模型过程噪声和传感器测量噪声，直线行驶工况下的轨迹预测误差控制在0.3 m以内，小曲率弯道行驶工况下的轨迹预测误差范围为1～9 m，大曲率弯道行驶工况下的轨迹预测误差范围为2～38 m；利用基于CTRV的轨迹预测模型结合EKF算法处理不确定性时，道路曲率的大小会直接影响车辆偏航角的滤波，甚至会使车辆偏航角滤波轨迹发散，导致大曲率弯道工况下的轨迹预测误差较大。

关键词：不确定性轨迹预测 CTRV模型误差 EKF算法

青少年特发性脊柱侧凸进展风险的表观遗传学因素研究进展

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重庆医学 2024年第9期53卷 1401-1405,1411页

作者：刘小梅王艳洋刘敏王谦四川大学华西医院康复医学中心成都610041

青少年特发性脊柱侧凸(AIS)是一种高度异质性疾病,一部分患者呈现明显的进行性加重,一部分患者则相对稳定。准确识别进展高风险患者有助于早期干预治疗,控制侧凸进展,并避免进展低风险患者的过度医疗。表观遗传学因素可动态调控基因的表... 详细信息

青少年特发性脊柱侧凸(AIS)是一种高度异质性疾病,一部分患者呈现明显的进行性加重,一部分患者则相对稳定。准确识别进展高风险患者有助于早期干预治疗,控制侧凸进展,并避免进展低风险患者的过度医疗。表观遗传学因素可动态调控基因的表达,不改变基因序列,充分反映遗传及环境的相互作用,在预测AIS的进展方面拥有巨大潜力。最近的研究报道了众多与AIS进展相关的表观遗传学因素,这些因素在AIS进展预测上显示出积极作用。该文对AIS进展风险的表观遗传学因素的研究进展进行综诉,期望为后续AIS的治疗及研究提供思路。

关键词：青少年特发性脊柱侧凸表观遗传学进展风险综述

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不同海况条件下舰载无人机着舰安全分析

哈尔滨工程大学学报 2024年第1期45卷 136-143页

作者：张子军张山王衍洋中国航空工业集团公司沈阳飞机设计研究所辽宁沈阳110035 北京航空航天大学航空科学与工程学院北京100083 北京航空航天大学江西研究院江西南昌330096

针对无人机上舰的使用需求,本文对舰载无人机着舰开展了系统的研究。建立了机-舰-环境综合模型和舰载无人机全自动着舰引导控制系统;基于建立的舰载无人机着舰综合模型对不同海况下的着舰过程进行仿真分析,研究不同海况条件以及航母不... 详细信息

针对无人机上舰的使用需求,本文对舰载无人机着舰开展了系统的研究。建立了机-舰-环境综合模型和舰载无人机全自动着舰引导控制系统;基于建立的舰载无人机着舰综合模型对不同海况下的着舰过程进行仿真分析,研究不同海况条件以及航母不同航速和遭遇角对着舰安全的影响。仿真研究表明:在复杂海况下,航母可通过适当提高航速以获得更高的着舰成功率,但过高的航速会导致舰尾流扰动加剧,使得着舰成功率显著下降;通过对仿真结果进行统计分析,给出了不同海况下的着舰安全范围,为无人机着舰辅助决策提供参考。

关键词：舰载机全自动着舰系统安全分析机舰适配性着舰控制技术无人机航母甲板运动

Exploring mission planning method for a team of carrier aircraft launching

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Chinese Journal of Aeronautics 2019年第5期32卷 1256-1267页

作者： Yu WU yanyang wang Xiangju QU Liguo SUN College of Aerospace Engineering Chongqing University School of Aeronautic Science and Engineering Beihang University

High-level efficiency and safety are of great significance for improving the fighting capability of an aircraft carrier. One way to enhance efficiency and safety level is to organize the carrier aircraft into combat effectively. This paper studies the mission planning problem for a team of carrier aircraft launching, and a novel distributed mission planning architecture is proposed. The architecture is hierarchical and is comprised of four levels, namely, the input level, the coordination level,the path planning level and the execution level. Realistic constraints in each level of the distributed architecture, such as the vortex flow effect, the crowd effect and the motion of aircraft, are considered in the model. To solve this problem, a distributed path planning algorithm based on the asynchronous planning strategy is developed. The proposed Mission Planning Approach for Carrier Aircraft Launching(MPACAL) is validated using the setups of the Nimitz-class aircraft *** to the isolated planning architecture and the centralized planning architecture, the proposed distributed planning architecture has advantages in coordinating the launch tasks not only belonging to the same catapult but also when all different catapults are considered. The proposed MPACAL provides a modeling method for the flight deck operation on aircraft carrier.

关键词： Aircraft carrier Carrier aircraft Distributed planning architecture Mission planning Path planning

Early-Middle Paleozoic Andes-type Continental Margin in the Chifeng Area, Inner Mongolia: Framework, Geochronology and Geochemistry and Implications for Tectonic Evolution of the Central Asian Orogenic Belt

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Acta Geologica Sinica(English Edition) 2020年第1期94卷 57-74页

作者： YAN Linjie XU Bei ZHANG Jiaming wang yanyang Key Laboratory of Orogenic Belts and Evolution Peking UniversityBeijing 100871China Key Laboratory of Regional Geology and Mineralization Hebei GEO UniversityShijiazhuang 050031China

Three tectonic units have been recognized in the Chifeng area, Inner Mongolia, from north to south, including the Qiganmiao accretionary prism, Jiefangyingzi arc belt and Sidaozhangpeng molasse basin, which formed an Andeantype active continent margin during the early to middle Paleozoic. The Qiganmiao accretionary prism is characterized by a mélange that consists of gabbro, two-mica quartz schist and basic volcanic rock blocks and heterogeneously deformed marble matrix. Two zircon U-Pb ages of 446.0±6.3 Ma and 1104±27 Ma have been acquired and been interpreted as the metamorphic and forming ages for the gabbro and two-mica quartz schist, respectively. The prism formed during the early to middle Paleozoic southward subduction of the Paleo Asian Ocean(PAO) and represents a suture between the North China craton(NCC) and Central Asian Orogenic Belt(CAOB). The Jiefangyingzi arc belt consists of pluton complex and volcanic rocks of the Xibiehe and Badangshan Formations, and Geochronology analysis indicates that the development of it can be divided into two stages. The first stage is represented by the Xibiehe Formation volcanic rocks, which belong to the subalkaline series, enriched LREE and LILE and depleted HFSE, with negative Eu anomalies, and plot in the volcanic arc field in discrimination diagrams. These characters indicate that the Xibiehe Formation results from to the continental arc magmatic activity related to the subduction of the PAO during 400–420 Ma. Magmatism of the second stage in 380–390 Ma consists of the Badangshan Formation volcanic rocks. Geochemistry analysis reveals that rhyolite, basaltic andesite and basalt of the Badangshan Formation were developed in continental margin arc setting. Moreover, the basaltic andesite and basalt display positive Sr anomalies, and the basalt have very low Nb/La values, suggesting that fluid is involved in magma evolution and the basalts were contaminated by continental crust. The sequence of Sidaozhangpeng molasse ba

关键词： Chifeng area andes-type continental margin early-middle paleozoic tectonic evolution Central Asian Orogenic Belt

Numerical Simulation of Aerodynamic Interaction Effects in Coaxial Compound Helicopters

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Fluid Dynamics & Materials Processing 2023年第5期19卷 1301-1315页

作者： Maosheng wang yanyang wang Yihua Cao Qiang Zhang School of Aeronautic Science and Engineering Beihang UniversityBeijing100191China

The so-called coaxial compound helicopter features two rigid coaxial rotors,and possesses high-speed ***,the small separation of the coaxial rotors causes severe aerodynamic interactions,which require careful *** the present work,the aerodynamic interaction between the various helicopter components is investigated by means of a numerical method considering both hover and forward flight *** a sliding mesh method is used to deal with the rotating coaxial rotors,the Reynolds-Averaged Navier-Stokes(RANS)equations are solved for the flow *** Caradonna&Tung(CT)rotor and Harrington-2 coaxial rotor are considered to validate the numerical *** results show that the aerodynamic interaction of the two rigid coaxial rotors significantly influences hover’s induced velocity and pressure *** addition,the average thrust of an isolated coaxial rotor is smaller than that of the corresponding isolated single *** with the isolated coaxial rotor,the existence of the fuselage results in an increment in the thrust of the ***,these interactions between the components of the considered coaxial compound helicopter decay with an increase in the advance ratio.

关键词： Coaxial compound helicopter aerodynamic interaction numerical simulation sliding mesh method