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Catalytic Enantioselective Simultaneous Control of Axial Chirality and Central Chirality in Allenes

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Chinese Journal of Chemistry 2018年第5期36卷 387-391页

作者： Jianxin Dai Xinyu Duan Jing Zhou chunling fu Shengming Ma Laboratory of MolecuJar Recognition and Synthesis Department of Chemistry Zhejian8 University Hangzhou Zhejiang 310027 China

Chiral molecules, which may contain one or more different type（s） of stereocentres, such as central, axial, planar, and helical chiralities, etc., are indispensable in chemistry, pharmaceutical industry, and life science. Despite many advances for the preparation of chiral molecules usually with a single type of chirality have been realized, simultaneous construction of different types of chiralities is still a significant challenge. Here, we wish to report a protocol for preparation of chiral allenes with both central and axial chiralities via a catalytic asymmetric allenylation of different biologically or syn- thetically useful fluorinated or non-fluorinated nucleophiles with readily available racemic allenes by using a single chiral ligand. An echoing between the central chirality and axial chirality for the enantioselectivity was observed. This strategy provides a general and practical approach to functionalized optically active allenes bearing both central and axial chiralities with an excellent enantioselectivity under mild conditions.

关键词： chiral palladium catalysis axial chirality central chirality simultaneous control allene

基于多新息最小二乘和多新息扩展卡尔曼滤波算法的锂电池SOC估计

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华南理工大学学报（自然科学版） 2024年第2期52卷 74-83页

作者：巫春玲付俊成徐先峰孟锦豪郑克军胡雯博长安大学能源与电气工程学院陕西西安710064 西安交通大学电气工程学院陕西西安710049

针对现有SOC(荷电状态)估计方法中电池模型参数恒定,没有考虑电池模型参数的动态变化,导致SOC的估计不够精准的问题,文中提出了一种基于电池模型参数在线辨识与SOC估计联合的算法。在二阶RC等效电路模型基础上,采用多新息最小二乘(Multi... 详细信息

针对现有SOC(荷电状态)估计方法中电池模型参数恒定,没有考虑电池模型参数的动态变化,导致SOC的估计不够精准的问题,文中提出了一种基于电池模型参数在线辨识与SOC估计联合的算法。在二阶RC等效电路模型基础上,采用多新息最小二乘(Multi Innovation Least Squares,MILS)算法对锂离子电池模型中的参数进行在线辨识,从而对电池模型进行实时修正;同时基于修正后的电池模型,采用多新息扩展卡尔曼滤波(Multi Innovation Extended Kalman Filter,MIEKF)算法对电池荷电状态进行估计。MILS算法可以解决在线参数辨识过程中的初始误差累积问题,能够实现模型参数的在线精准辨识,MIEKF算法融合了多新息理论和卡尔曼滤波理论,加入了遗忘因子以削弱历史数据并修正权重,解决了数据过饱和问题,具有较高的准确性和收敛性。实验结果表明,在对电池模型进行参数辨识时,MILS算法、RLS算法辨识的均方根误差分别为1.4、1.9 mV,MILS算法相比RLS算法的估计精度提高了26.3%;对于参数辨识后SOC的估计,MIEKF算法估计的均方根误差为0.0037,EKF算法、AEKF算法估计的均方根误差分别为0.0073、0.0052,MIEKF算法比EKF算法的估计精度提高了49.31%,比AEKF算法的估计精度提高了28.84%;并且在给定SOC初值错误的情况下,文中所提出算法在电池开始工作后30 s左右就能够收敛到真实值,是一种精度高而且鲁棒性好的有效估计方法。

关键词： SOC估计多新息参数辨识扩展卡尔曼滤波

老年缺血性卒中后轻度认知障碍患者眼-视功能障碍与认知功能的关系研究

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中国卒中杂志 2024年第2期19卷 167-172页

作者：傅春玲宋碧英杨大会重庆大学附属三峡医院眼科重庆404000 陆军军医大学陆军特色医学中心眼科

目的探讨老年卒中后轻度认知障碍(post-stroke mild cognitive impairment,PSMCI)患者眼-视功能障碍与认知功能的关系。方法前瞻性连续纳入2020年2月—2022年2月重庆大学附属三峡医院收治的急性缺血性卒中患者资料。采用MMSE、MoCA量... 详细信息

目的探讨老年卒中后轻度认知障碍(post-stroke mild cognitive impairment,PSMCI)患者眼-视功能障碍与认知功能的关系。方法前瞻性连续纳入2020年2月—2022年2月重庆大学附属三峡医院收治的急性缺血性卒中患者资料。采用MMSE、MoCA量表评估患者的认知功能,并检测双眼视力、眼球转动运动、视野、视觉感知和视觉注意力。根据6个月随访是否发生PSMCI将患者分为PSMCI组和无PSMCI组。收集患者的临床资料,采用多因素logistic回归分析急性缺血性卒中患者发生PSMCI的危险因素。结果共纳入157例患者,71例(45.22%)发生PSMCI,108例(68.79%)发生眼-视功能障碍,其中58例(53.70%)为中心视力受损,30例(27.78%)为视野丧失,41例(37.96%)为眼运动异常,30例(27.78%)为视觉知觉障碍。PSMCI组眼-视功能障碍总发生率以及中心视力受损、眼球运动异常、视野丧失、视觉知觉障碍发生率高于无PSMCI组,年龄高于无PSMCI组,差异有统计学意义(均P<0.05)。高龄(OR 1.919,95%CI 1.310~2.813,P<0.001)、入院时高NIHSS评分(OR 2.291,95%CI 1.423~3.689,P<0.001)、大体积梗死(OR 1.669,95%CI 1.203~2.315,P<0.001)、眼-视功能障碍(OR 1.998,95%CI 1.363~2.928,P<0.001)是急性缺血性卒中患者发生PSMCI的危险因素(均P<0.05)。结论眼-视功能障碍与急性缺血性卒中患者PSMCI有关,眼-视功能障碍可能加重认知功能损伤。

关键词：卒中后轻度认知障碍眼-视功能障碍认知功能危险因素

畜禽车厢体内温度和流场数值CFD模拟及验证

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中国农机化学报 2024年第5期45卷 85-90,97页

作者：苗永存马嘉楠蒋春玲王镇江傅爱军广西科技大学机械与汽车工程学院广西柳州545000 中国重汽集团柳州运力专用汽车有限公司广西柳州545000

为研究畜禽运输车厢体内环境的分布情况以及对温度场进行评估,利用计算流体力学(CFD)的方法,模拟出在空载及满载条件下内气流流场和温度场的分布情况,同时根据空载模拟结果提出优化方案并模拟。测量与分析厢体内关键位置的温度和风速,... 详细信息

为研究畜禽运输车厢体内环境的分布情况以及对温度场进行评估,利用计算流体力学(CFD)的方法,模拟出在空载及满载条件下内气流流场和温度场的分布情况,同时根据空载模拟结果提出优化方案并模拟。测量与分析厢体内关键位置的温度和风速,并与模拟值比较。结果表明:模拟空载时模拟值与测量值最大绝对误差1.7℃,模拟得到厢体的温度分布变化情况和测量值所得结果一致,风速值相对误差范围在3%以下的有22个点。优化后厢体内温度均匀度改善明显,温度变化幅度小;满载时,温度分布与空载相似,但整体温度有些许上升。验证CFD模型的正确性,为优化提供可靠基础。

关键词：畜禽运输车计算流体力学温度场气流流场

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都市圈轨道交通多网融合的信号系统方案研究

铁路通信信号工程技术 2024年第1期21卷 1-9页

作者：池春玲张伟宋睿符萌中铁第四勘察设计院集团有限公司武汉430063

结合都市圈网络化、公交化特点,提出都市圈轨道交通信号系统融合的技术目标,即采用现有技术C2/C2+ATO与CBTC系统的融合以及采用新型互联互通技术的信号系统间的融合。分析现有信号主流的CTCS系统与CBTC系统的地面和车载设备在技术层面... 详细信息

结合都市圈网络化、公交化特点,提出都市圈轨道交通信号系统融合的技术目标,即采用现有技术C2/C2+ATO与CBTC系统的融合以及采用新型互联互通技术的信号系统间的融合。分析现有信号主流的CTCS系统与CBTC系统的地面和车载设备在技术层面、工作机理、系统功能等差异的基础上提出“地对车兼容”和“车对地兼容”的互联互通方案,结合各目前相关单位在开展的研究情况,分析新型市域铁路互联互通技术路线。

关键词：多网融合信号系统中国列车运行控制系统基于通信的列车控制系统

Maneuvering Multi-target Tracking Algorithm Based on Modified Generalized Probabilistic Data Association

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Engineering（科研） 2011年第12期3卷 1155-1160页

作者： Zhentao Hu chunling fu Xianxing Liu 不详

Aiming at the problem of strong nonlinear and effective echo confirm of multi-target tracking system in clutters environment, a novel maneuvering multitarget tracking algorithm based on modified generalized probabilistic data association is proposed in this paper. In view of the advantage of particle filter which can deal with the nonlinear and non-Gaussian system, it is introduced into the framework of generalized probabilistic data association to calculate the residual and residual covariance matrices, and the interconnection probability is further optimized. On that basis, the dynamic combination of particle filter and generalized probabilistic data association method is realized in the new algorithm. The theoretical analysis and experimental results show the filtering precision is obviously improved with respect to the tradition method using suboptimal filter.

关键词： Multi-Target Tracking Particle Filter Generalized Probabilistic Data Association Clutters

A novel multi-sensor multiple model particle filter with correlated noises for maneuvering target tracking

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High Technology Letters 2014年第4期20卷 355-362页

作者：胡振涛 fu chunling Institute of Image Processing and Pattern Recognition Henan University School of Physics and Electronics Henan University

Aiming at the effective realization of particle filter for maneuvering target tracking in multi-sensor measurements,a novel multi-sensor multiple model particle filtering algorithm with correlated noises is proposed.Combined with the kinetic evolution equation of target state,a multi-sensor multiple model particle filter is firstly constructed,which is also used as the basic framework of a new algorithm.In the new algorithm,in order to weaken the adverse influence from random measurement noises in the measuring process of particle weight,a weight optimization strategy is introduced to improve the reliability and stability of particle weight.In addition,considering the correlated noise existing in the practical engineering,a decoupling method of correlated noise is given by the rearrangement and transformation of the state transition equation and measurement equation.Since the weight optimization strategy and noise decoupling method adopt respectively the center fusion structure and the off-hne way,it improves the adverse effect effectively on computational complexity for increasing state dimension and sensor number.Finally,the theoretical analysis and experimental results show the feasibility and efficiency of the proposed algorithm.

关键词：粒子滤波算法机动目标跟踪相关噪声多传感器多模型动力学演化方程状态转移方程目标状态

Simulation of SLD Impingement on Wind Turbine Blade Airfoil

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第1期33卷 112-120页

作者： Zhu Chengxiang Zhu chunling fu Bin ZhaoHuanyu Key Laboratory of fundamental Science for National Defense Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China Science and Technology on Space Physics Laboratory Beijing 100076P.R.China

Accurate prediction of droplet impingement on wind turbine blade is one of the most important premises of anti-icing and de-icing system design.In a super-cooled large droplets(SLD)conditions,droplet no longer maintains a sphere shape,and it may deform,break up,and splash when moving or impinging on the surface.Semi-empirical models of droplet dynamic behaviours are embedded into the Eulerian droplet model to improve the accuracy of the numerical simulation of droplet impingement limits and local collection efficiency.Eulerian droplet model(Model 1)for small droplets and improved Eulerian droplet model(Model 2)for large droplet are both validated by comparing to the wind tunnel experiment results.Using the proposed methods,droplet impingement limitation and local collection efficiency on the S809 airfoil are calculated in various conditions.A detailed derivation of Model 1and Model 2is presented along with a comparison of numerical trajectories,drag coefficient and collection efficiency distributions.The results show that droplet dynamic behaviours,including splashing,break-up and deforming,must be considered to accurately simulate the impingement behaviour in the SLD conditions.And with the increase of the droplet diameters,the effects of the droplet dynamic behaviors on the impingement characteristics are more obvious.

关键词： wind turbine icing super large droplet droplet deformation splash

Catalytic Asymmetric Allenylation of Malonates Generating a Central Chirality

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Catalytic Asymmetric Allenylation of Malonates Generating a ...