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Chinese Journal of Aeronautics 2024年第10期37卷 275-293页

作者： Qi yu Wanchun CHEN wenbin yu School of Astronautics Beihang UniversityBeijing 102206China

In the scenario that a solid-fuel launch vehicle maneuvers in outer space at high angles of attack and sideslip for energy management,Approximate Analytical Solutions(AAS)for the threedimensional(3D)ascent flight states are derived,which are the only solutions capable of considering time-varying Mass Flow Rate(MFR)at *** uneven MFR makes the thrust vary nonlinearly and thus increases the difficulty of the problem *** AAS are derived based on a 3D Generalized Ascent Dynamics Model(GADM)with a normalized mass as the independent *** simplify some highly nonlinear terms in the GADM,several approximate functions are introduced carefully,while the errors of the approximations relative to the original terms are regarded as minor ***,a finite series with positive and negative exponents,called Exponent-Symmetry Series(ESS),is proposed for function approximation to decrease the highest exponent in the AAS so as to reduce computer round-off *** calculate the ESS coefficients,a method of seeking the Optimal Interpolation Points(OIP)is proposed using the leastsquares-approximation *** to the artful design of the approximations,the GADM can be decomposed into two analytically solvable subsystems by a perturbation method,and thus the AAS are obtained ***,to help implement the AAS,two indirect methods for measuring the remaining mass and predicting the burnout time in flight are put forward using information from *** results verify the superiority of the AAS under the condition of time-varying MFR.

关键词： Approximate analytical solutions 3D ascent trajectory Solid-fuel launch vehicle Uneven thrust Energy management

3D Localization for Multiple AUVs in Anchor-Free Environments by Exploring the Use of Depth Information

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1051-1053页

作者： Yichen Li wenbin yu Xinping Guan the Department of Automation Shanghai Jiao Tong UniversityShanghai 200240 the Key Laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai Jiao Tong UniversityShanghai 200240China

Dear Editor,This letter investigates the cooperative localization problem for multiple autonomous underwater vehicles(AUVs)in underwater anchor-free environments,where AUV localization errors grow without bound due to the accumulated errors in inertial measurements(termed accumulated errors hereafter)and the lack of anchors(with known positions).

关键词： AUVs underwater hereafter

Real-time tracking of fast-moving object in occlusion scene

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Journal of Systems Engineering and Electronics 2024年第3期35卷 741-752页

作者： LI yuran LI Yichen ZHANG Monan yu wenbin GUAN Xinping Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Systems Control and Information Processing Ministry of Education of ChinaShanghai 200240China

Tracking the fast-moving object in occlusion situations is an important research topic in computer vision. Despite numerous notable contributions have been made in this field,few of them simultaneously incorporate both object's extrinsic features and intrinsic motion patterns into their methodologies,thereby restricting the potential for tracking accuracy improvement. In this paper, on the basis of efficient convolution operators(ECO) model, a speed-accuracy-balanced model is put forward. This model uses the simple correlation filter to track the object in real-time, and adopts the sophisticated deep-learning neural network to extract high-level features to train a more complex filter correcting the tracking mistakes, when the tracking state is judged to be poor. Furthermore, in the context of scenarios involving regular fast-moving, a motion model based on Kalman filter is designed which greatly promotes the tracking stability, because this motion model could predict the object's future location from its previous movement pattern. Additionally,instead of periodically updating our tracking model and training samples, a constrained condition for updating is proposed,which effectively mitigates contamination to the tracker from the background and undesirable samples avoiding model degradation when occlusion happens. From comprehensive experiments, our tracking model obtains better performance than ECO on object tracking benchmark 2015(OTB100), and improves the area under curve(AUC) by about 8% and 32% compared with ECO, in the scenarios of fast-moving and occlusion on our own collected dataset.

关键词： speed-accuracy balanced motion modeling constrained updater

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新能源汽车储能系统快速充电策略研究综述

电气工程学报 2024年第1期19卷 23-32页

作者：金英爱余文宾马纯强吉林大学汽车仿真与控制国家重点实验室长春130022 吉林大学汽车工程学院长春130022

电动汽车在近十年得到大力发展与推广,但续航里程一直限制着电动汽车的进一步发展。车载储能系统快速充电技术能够有效缓解现阶段电动汽车用户续航里程焦虑,同时提高车辆安全性。电动汽车快速充电技术包括基于经验的充电策略和基于优化... 详细信息

电动汽车在近十年得到大力发展与推广,但续航里程一直限制着电动汽车的进一步发展。车载储能系统快速充电技术能够有效缓解现阶段电动汽车用户续航里程焦虑,同时提高车辆安全性。电动汽车快速充电技术包括基于经验的充电策略和基于优化的充电策略。本文首先总结了各种传统充电方法的优点和缺点,其次根据应用场景优化目标的不同,归纳了不同优化目标的快充策略的应用,此外总结了电池内部的电极材料、电解质和电极/电解质界面(EEI)对快充性能的影响,并归纳了不同材料的改良措施,并对该领域未来发展方向进行了展望。

关键词：电动汽车充电策略锂电池电极材料快充性能

Current-Aided Multiple-AUV Cooperative Localization and Target Tracking in Anchor-Free Environments

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IEEE/CAA Journal of Automatica Sinica 2023年第3期10卷 792-806页

作者： Yichen Li wenbin yu Xinping Guan Department of Automation Shanghai Jiao Tong UniversityShanghai 200240 Key Laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai Jiao Tong UniversityShanghai 200240China IEEE

In anchor-free environments,where no devices with known positions are available,the error growth of autonomous underwater vehicle(AUV)localization and target tracking is unbounded due to the lack of references and the accumulated errors in inertial *** paper aims to improve the localization and tracking accuracy by involving current information as extra *** first integrate current measurements and maps with belief propagation and design a distributed current-aided message-passing scheme that theoretically solves the localization and tracking *** on this scheme,we propose particle-based cooperative localization and target tracking algorithms,named CaCL and CaTT,*** AUV localization,CaCL uses the current measurements to correct the predicted and transmitted position information and alleviates the impact of the accumulated errors in inertial *** target tracking,the current maps are applied in CaTT to modify the position prediction of the target which is calculated through historical *** effectiveness and robustness of the proposed methods are validated through various simulations by comparisons with alternative methods under different trajectories and current conditions.

关键词： Anchor-free belief propagation cooperative localization current-aided target tracking

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电解锰渣库周边土壤重金属污染特征评价

环境科学与技术 2024年第3期47卷 179-191页

作者：付晓辛肖雪谭道永徐中慧于文彬西南科技大学固体废物处理与资源化教育部重点实验室四川绵阳621010 中国科学院地球化学研究所矿床地球化学国家重点实验室贵州贵阳550081

中国作为全世界最大的电解锰生产国,电解锰渣堆存造成的土壤污染亟需改善。该研究在中国锰矿资源储量最大的基地——贵州省铜仁市,选取辖区公共电解锰渣库(玉屏侗族自治县蔡溪村),利用湿式消解法及改进的BCR三步提取法对Mn、Zn、Pb、Ni... 详细信息

中国作为全世界最大的电解锰生产国,电解锰渣堆存造成的土壤污染亟需改善。该研究在中国锰矿资源储量最大的基地——贵州省铜仁市,选取辖区公共电解锰渣库(玉屏侗族自治县蔡溪村),利用湿式消解法及改进的BCR三步提取法对Mn、Zn、Pb、Ni、Cr、Cd 6种重金属元素在电解锰渣库周边土壤中的污染特征、形态分布及风险评价进行分析讨论。Mn、Pb和Cd是对渣库周边土壤环境质量影响最大的重金属。Mn含量变化范围为356~14915 mg/kg,平均值为3828 mg/kg,超过贵州土壤背景值4.8倍。Pb和Cd的平均含量是农用地土壤国家标准风险筛选值的3.1和40.2倍。6种重金属均以可迁移的酸溶解态为主。Mn和Cd的弱酸提取态含量随距渣库坝体越近而显著增加(P<0.05)。普通Kriging空间插值结果发现Mn、Cd、Zn、Pb和Ni 5种重金属含量具有中等强度的空间相关性,其中Mn和Cd含量受到人为活动污染等随机影响较大。Mn和Cd空间分布总体呈东高西低,高值均出现在电解锰渣库坝体附近。主成分分析法显示Mn、Cd和Pb主要受电解锰渣库污染影响;Ni和Zn主要来源于附近农业活动和工业生产;Cr主要受地质背景因素影响。电解锰渣库周边土壤潜在生态风险指数为最高风险等级,其中Cd的贡献比例最大(91%)。

关键词：电解锰渣土壤重金属污染形态分布源解析生态风险

A progress review of practical soot modelling development in diesel engine combustion

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第3期7卷 269-281页

作者： Feiyang Zhao Wenming Yang wenbin yu Department of Mechanical Engineering National University of SingaporeSingapore 117575Singapore

Great efforts have been made over the last few decades in understanding of the mechanisms and phenomenology of soot formation and burnout in combustion *** this paper,theoretical advances in modelling soot formation and oxidation under engine circumstance are surveyed based on the published works,particularly focus on the practical soot modelling coupled with engine computational fluid dynamics(CFD)numerical *** types of soot models can be divided up into three main groups:empirical,semi-empirical and detailed soot *** the development of computing technology and increasingly comprehensive soot fundamental knowledge,the semi-empirical phenomenological soot model with major generic processes of soot formation was proposed,which is one of the most extensively investigated soot models in recent *** is highlighted with solving mathematical equations to get soot particle number density,soot volume and mass *** coupled with fuel chemistry,the detailed soot model seeks to predict soot characteristics based on molecule structure,bringing further insight of the soot evolution and transient behavior of soot-relevant ***,the sooting tendency from engine combustion fueled with alternative and oxygenated fuels are able to be further explored,which is conductive to propose new engine technologies for soot mitigation and future fuel strategy.

关键词： Engine combustion Alternative fuel Numerical modelling Soot formation

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甲状腺癌相关基因检测的研究进展

中国肿瘤外科杂志 2024年第3期16卷 308-313页

作者：安文超于文斌内蒙古医科大学研究生院内蒙古呼和浩特010000 北京大学肿瘤医院内蒙古医院头颈外科内蒙古呼和浩特010000

甲状腺癌是头颈外科最常见的恶性肿瘤,也是最常见的内分泌恶性肿瘤之一。部分类型的甲状腺癌手术治疗的效果不佳,放化疗的敏感性也较低,为寻找更好的治疗方案,近年来研究发现鼠类肉瘤滤过性毒菌致癌同源体B1(BRAF)、转染重排(RET/PTC)... 详细信息

甲状腺癌是头颈外科最常见的恶性肿瘤,也是最常见的内分泌恶性肿瘤之一。部分类型的甲状腺癌手术治疗的效果不佳,放化疗的敏感性也较低,为寻找更好的治疗方案,近年来研究发现鼠类肉瘤滤过性毒菌致癌同源体B1(BRAF)、转染重排(RET/PTC)、端粒酶反转录酶(TERT)、肿瘤蛋白53(P53)、鼠肉瘤病毒(RAS)等基因的突变和重排是导致甲状腺癌发生发展的重要原因,可以通过相关基因检测来预测甲状腺癌的良恶性以及预后情况,并且可以帮助确定治疗靶点从而进一步使用靶向药物来治疗这一部分难治性甲状腺癌。了解甲状腺癌患者的基因突变情况,对于明确其发病机制、制定个体化治疗方案都有很重要的意义。文章对相关基因与癌症发生之间的关系以及基因的研究进展做了概述,旨在为甲状腺癌临床诊治提供参考。

关键词：甲状腺癌鼠类肉瘤滤过性毒菌致癌同源体B1 转染重排端粒酶反转录酶 P53 鼠肉瘤病毒

MCM-41负载磁铁矿纳米颗粒及其对Cu(Ⅱ)的吸附特征

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矿物学报 2024年第2期44卷 155-164页

作者：于文彬覃宗华周楼许善胜于文霖万泉中国科学院地球化学研究所矿床地球化学国家重点实验室贵州贵阳550081 贵州师范学院化学与材料学院贵州贵阳550018 桂林理工大学材料科学与工程学院广西壮族自治区桂林541004

本研究通过共沉淀法制备了MCM-41负载磁铁矿纳米颗粒(MCM-41/Mag),并研究了其结构、热稳定性及对Cu(Ⅱ)的吸附特征。MCM-41/Mag中磁铁矿纳米颗粒分布在MCM-41的外表面及介孔孔道内,w(磁铁矿)为17.33%的负载型样品(MCM-41/Mag_(0.3))的... 详细信息

本研究通过共沉淀法制备了MCM-41负载磁铁矿纳米颗粒(MCM-41/Mag),并研究了其结构、热稳定性及对Cu(Ⅱ)的吸附特征。MCM-41/Mag中磁铁矿纳米颗粒分布在MCM-41的外表面及介孔孔道内,w(磁铁矿)为17.33%的负载型样品(MCM-41/Mag_(0.3))的比表面积为631.6 m^(2)/g,远高于纯磁铁矿纳米颗粒(Mag-NPS)的91.1 m^(2)/g,这归因于磁铁矿纳米颗粒在MCM-41上良好的分散性及载体巨大的比表面积。DSC结果表明MCM-41/Mag_(0.3)中磁铁矿的相变温度显著高于Mag-NPS。MCM-41/Mag_(0.3)吸附Cu(Ⅱ)在120 min可达到平衡,其吸附等温线符合Sips模型,最大吸附量为10.44 mg/g,吸附机理包括化学吸附和物理吸附,部分Cu(Ⅱ)可与磁铁矿表面形成Fe—O—Cu共价键,部分Cu(Ⅱ)通过静电作用吸附在样品表面。MCM-41/Mag_(0.3)中单位磁铁矿对Cu(Ⅱ)的最大吸附量可达62.78 mg/g,显著高于文献报道的其他铁(氢)氧化物。由于其快的吸附速率和高的吸附能力,MCM-41/Mag_(0.3)可作为Cu(Ⅱ)吸附材料用于水体中重金属离子的去除。本研究结果有助于拓展磁铁矿在环境治理领域的应用并为开发性能良好的重金属吸附剂提供理论参考。

关键词：磁铁矿负载吸附重金属 Cu(Ⅱ)

The Compaction Characteristics of Hot Mixed Asphalt Mixtures

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Journal of Wuhan University of Technology(Materials Science) 2014年第5期29卷 956-959页

作者：高英 HUANG Xiaoming yu wenbin School of Transportation Southeast University Zhuhai Highway Bureau

The quality of compaction is important to the performance of hot mixed asphalt （HMA） pavement. Most premature failures of asphalt pavement are concerned with poor compaction. Compaction characteristic of lIMA mixtures were studied. Compaction tests were done with typical widely used HMA mixtures, including dense gradation asphalt mixtures with different nominal maximum aggregate size （AC13,AC20,AC25）, and mixtures with different gradation （AC13, SMA13,Supl3 and OGFC13）. HMA mixtures were sampled at different compaction temperature and Marshall blow numbers, varying between 60 and 175 ~C and between 15 and 75 lows, respectively. The compaction characteristics of these mixtures were evaluated. The results showed that the Marshall stability and volumetric properties were significantly affected by the compaction temperature. Mixtures with the same NMAS but different type of gradation need different compaction energy to get the designed density.

关键词： compaction characteristic hot mixed asphalt compaction temperature marshall blow number gradation