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整车制造工厂车身影响因素产能仿真

工业控制计算机 2024年第4期37卷 118-119页

作者：方建程上汽通用汽车有限公司整车制造工程部上海201208

车间柔性生产方案在受到限制时会存在一定的调控策略,实际生产和理论分析间存在差异,利用Plant Simulation软件,结合现场生产实际可调控策略对某车身车间进行了建模分析,分析该车身车间载具切换和空放情况下应满足的车型配比和调控策略... 详细信息

车间柔性生产方案在受到限制时会存在一定的调控策略,实际生产和理论分析间存在差异,利用Plant Simulation软件,结合现场生产实际可调控策略对某车身车间进行了建模分析,分析该车身车间载具切换和空放情况下应满足的车型配比和调控策略,并分析影响该车身车间产能和运行的因素,分析方法可供后续借鉴。

关键词： Plant Simulation 二次开发车身车间

Start-up current adaptive control for sensorless high-speed brushless DC motors based on inverse system method and internal mode controller

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Chinese Journal of Aeronautics 2017年第1期30卷 358-367页

作者： He Yanzhao Zheng Shiqiang fang jiancheng School of Instrumentation Science and Opto-electronics Engineering Beihang University Beijing 100083 China Beijing Engineering Research Center of High-Speed Magnetically Suspended Motor Technology and Application Beijing 100083 China

The start-up current control of the high-speed brushless DC（HS-BLDC） motor is a challenging research topic. To effectively control the start-up current of the sensorless HS-BLDC motor, an adaptive control method is proposed based on the adaptive neural network（ANN）inverse system and the two degrees of freedom（2-DOF） internal model controller（IMC）. The HS-BLDC motor is identified by the online least squares support vector machine（OLS-SVM） algorithm to regulate the ANN inverse controller parameters in real time. A pseudo linear system is developed by introducing the constructed real-time inverse system into the original HS-BLDC motor system. Based on the characteristics of the pseudo linear system, an extra closed-loop feedback control strategy based on the 2-DOF IMC is proposed to improve the transient response performance and enhance the stability of the control system. The simulation and experimental results show that the proposed control method is effective and perfect start-up current tracking performance is achieved.

关键词： Adaptive control Brushless DC motors Inverse systems Internal model controller Neural networks Start-up Support vector machines

A transfer alignment method for airborne distributed POS with three-dimensional aircraft flexure angles

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Science China(Information Sciences) 2018年第9期61卷 190-204页

作者： Xiaolin GONG Longjun CHEN jiancheng fang Gang LIU School of Instrumentation Science and Opto-electronics Engineering Beihang University Science and Technology on Inertial Laboratory Beihang University

An airborne distributed position and orientation system(POS) appears to satisfy the requirement of multi-point motion parameters measurement. This relies on transfer alignment from a high precision master system to slave systems to obtain high accuracy motion parameters of all points. A key problem for a distributed POS involves determining a method to treat the aircraft flexure appropriately and achieve high precision transfer alignment. In this study, the effect of aircraft flexure on transfer alignment accuracy for airborne earth observation is first analyzed. Based on this, the error model of transfer alignment that considers three-dimensional flexure angles are established, and a transfer alignment based on parameter identification unscented Rauch-Tung-Striebel smoother(PIURTSS) is proposed. The simulations results show that the transfer alignment method based on PIURTSS effectively improves the estimation accuracy.

关键词： position and orientation system distribution airborne earth observation transfer alignment unscented transformation Rauch-Tung-Striebel smoother

Interlaced optimal-REQUEST and unscented Kalman filtering for attitude determination

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Chinese Journal of Aeronautics 2013年第2期26卷 449-455页

作者： Quan Wei Xu Liang Zhang Huijuan fang jiancheng Science and Technology on Inertial Laboratory Key Laboratory of Fundamental Science for National Defense-Novel Inertial Instrument & Navigation System Technology Beihang University

Aimed at low accuracy of attitude determination because of using low-cost components which may result in non-linearity in integrated attitude determination systems, a novel attitude determination algorithm using vector observations and gyro measurements is presented. The various features of the unscented Kalman filter （UKF） and optimal-REQUEST （quaternion estimator） algorithms are introduced for attitude determination. An interlaced filtering method is presented for the attitude determination of nano-spacecraft by setting the quaternion as the attitude representation, using the UKF and optimal-REQUEST to estimate the gyro drifts and the quaternion, respectively. The optimal-REQUEST and UKF are not isolated from each other. When the optimal-REQUEST algorithm estimates the attitude quaternion, the gyro drifts are estimated by the UKF algorithm synchronously by using the estimated attitude quaternion. Furthermore, the speed of attitude determination is improved by setting the state dimension to three. Experimental results show that the presented method has higher performance in attitude determination compared to the UKF algorithm and the traditional interlaced filtering method and can estimate the gyro drifts quickly.

关键词： Attitude determination Hybrid simulation Interlaced filtering Optimal-REQUEST Unscented Kalman filter

Adaptive two-filter smoothing based on second-order divided difference filter for distributed position and orientation system

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Science China(Information Sciences) 2019年第9期62卷 130-143页

作者： Jianli LI Siyuan ZOU Bin GU jiancheng fang School of Instrument Science and Opto-electronic Engineering Beihang University

The distributed position and orientation system(POS) uses transfer alignment to accurately measure multi-node time-spatial reference information, which is necessary for compensating the motion error of imaging sensors used in aerial surveys. Lever-arm deformation in transfer alignment will result in time-varying covariance of measurement noise, which decreases the estimation accuracy. To address this problem, a second-order adaptive divided difference two-filter smoother(ADDTFS) is proposed for transfer alignment. The second-order adaptive divided difference filter(ADDF2) severs as the forward filter to address nonlinearity in the system. The ADDF2 can estimate the measurement noise covariance in real time based on adaptive estimation using innovation information. The weighted statistical linear regression formulation is used in the backward filter to independently estimate the states and error covariance *** the forward and backward results are combined, to obtain high-precision estimation results in postprocessing. Finally, the vehicle experiment results show that the proposed method can improve the attitude precision of transfer alignment in a distributed POS by 27.84%, which has been successfully applied to motion compensation of airborne interferometric synthetic aperture radar(InS AR).

关键词： distributed POS transfer alignment integrated navigation two-filter smoother divided difference filter

单用不同浓度总丹参酮及联合酪氨酸激酶抑制剂对人髓系白血病细胞株增殖抑制和促凋亡作用研究

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中华医学杂志 2024年第17期104卷 1514-1520页

作者：周晓苏房建成马小丽张阳王芳陈雪吴祁生曹泮翔刘红星北京陆道培血液病研究院分子医学研究中心，北京100176 河北燕达陆道培医院检验医学科，廊坊065201 北京陆道培医院病理和检验医学科，北京100176

目的探讨单用不同浓度总丹参酮及联合酪氨酸激酶抑制剂(TKIs)对人髓系白血病细胞株的增殖抑制和促凋亡作用,并研究其分子机制。方法K562和Kasumi-1细胞株购自中国科学院上海细胞库,TKIs耐药株K562/T315I细胞株由北京陆道培血液病研究院... 详细信息

目的探讨单用不同浓度总丹参酮及联合酪氨酸激酶抑制剂(TKIs)对人髓系白血病细胞株的增殖抑制和促凋亡作用,并研究其分子机制。方法K562和Kasumi-1细胞株购自中国科学院上海细胞库,TKIs耐药株K562/T315I细胞株由北京陆道培血液病研究院分子医学研究中心自主构建。取对数生长期细胞,设0、2.19、4.38、8.75、17.50、35.00μg/ml总丹参酮干预组,按1×104个/孔接种于96孔板后,加药处理24 h;另设二甲基亚砜对照组。所有实验独立重复3~5次,CCK-8法检测细胞增殖活性,流式细胞术检测细胞凋亡率,Western印迹法检测细胞凋亡调控蛋白Bcl-2和Bax的表达水平。将经总丹参酮处理和未处理的细胞株进行转录组测序,对差异表达的基因进行基因集富集分析。结果8.75μg/ml总丹参酮作用K562、K562/T315I和Kasumi-1细胞24 h后,半抑制浓度值(IC 50)分别为(4.11±0.02)、(4.95±0.04)和(3.98±0.01)μg/ml。8.75μg/ml总丹参酮与0.25μmol/L伊马替尼联合应用时,总丹参酮可增强伊马替尼对K562和K562/T315I细胞株的凋亡诱导作用。分别用4.38、8.75、17.50μg/ml总丹参酮作用于K562、K562/T315I和Kasumi-1细胞株24 h,与对照组比较,总丹参酮可以上调Bax蛋白表达水平,下调Bcl-2蛋白表达水平,降低Bcl-2/Bax比值(均P<0.05)。总丹参酮抑制髓系白血病细胞株增殖相关信号通路和DNA损伤修复通路,激活诱导白血病细胞凋亡的信号通路。结论不同浓度总丹参酮对K562、Kasumi-1以及TKIs耐药的K562/T315I细胞株有抑制增殖和促进凋亡的作用,与TKIs联合应用时可进一步增强抗白血病作用。

关键词：白血病,髓样总丹参酮酪氨酸激酶抑制剂凋亡分子机制

Angular velocity estimation using characteristics of star trails obtained by star sensor for spacecraft

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Science China(Information Sciences) 2021年第1期64卷 201-214页

作者： Xiaolin NING Pingping CHEN Yueqing HUANG Weiren WU jiancheng fang School of Instrumentation Science & Opto-electronics Engineering Beihang University Lunar Exploration and Space Program Center China National Space Administration

Many studies have been conducted about angular velocity estimation using star sensors, and fairly good performance is achieved when the spacecraft is working at low-dynamic environments. However,when the spacecraft rotates at a large angular velocity, the star image will become blurred, which makes it difficult to identify and recognize star centroids, which, in turn, reduces the accuracy of angular velocity estimation. Therefore, to solve the problem with angular velocity estimation in highly dynamic situations,this research studies a method of angular velocity estimation using blurred star images. The length and ending point coordinates of star trails obtained from these blurred star images are used for a series of processes, which includes the pre-processing of blurred star images, determination of starting and ending points, thinning and selection of star trails, and calculation of trail lengths. Simulations show that the effectiveness of the proposed method in highly dynamic situations and the angular velocity estimation errors in constant and sinusoidal variation are reduced by at least 66% and 62%, respectively, compared with those of the traditional method.

关键词： angular velocity estimation star sensor blurred star images star trail characteristics unscented Kalman filter

Fast Position and Velocity Determination for Pulsar Navigation Using NML and LSM

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Chinese Journal of Electronics 2017年第6期26卷 1325-1329页

作者： LIU Jin WU Jin XIONG Ling fang jiancheng LIU Gang College of Information Science and Engineering Wuhan University of Science and Technology School of Instrumentation Science and Opto-electronics Engineering Beihang University

To reduce the computational cost, a Fast position and velocity joint determination(FPVD) method based on the Near-maximum likelihood(NML) and the Least square method(LSM) is proposed for X-ray pulsar navigation. Considering the fact that the Doppler effects caused by the velocity of the spacecraft alters the X-ray pulse Time-of-arrival(TOA), we adopt the NML to obtain multi-TOAs, and then utilize the LSM to estimate the variation of TOAs instead of the pulsar profile distortion adopted by the Maximum-likelihood(ML) estimation method. Finally, according to the variation value and TOAs, the position and velocity information of the spacecraft are calculated. The simulation results have demonstrated that the FPVD method is far faster than the ML estimation method, and its accuracy approaches the CramerRao lower bound(CRLB).

关键词： Velocity determination Pulsar Maximum likelihood Least square method

Optical Rotation Detection for Atomic Spin Precession Using a Superluminescent Diode

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Photonic Sensors 2019年第2期9卷 135-141页

作者： Xuejing LIU Yang LI Hongwei CAI Ming DING jiancheng fang Wei JIN School of Inst ru men ta tion Science and Opto-electronics Engineering Beihang University Beijing 100191 China

A superluminescent diode (SLD) as an alternative of laser is used to detect optical rotation for atomic spin precession. A more uniform Gauss configuration without additional beam shaping and a relatively high power of the SLD have a potential for atomic magnetometers, which is demonstrated in theory and experiments. In addition, the robustness and compactness enable a more practical way for optical rotation detections, especially for applications in magnetoencephalography systems.

关键词： Superluminescent diode atomic magnetometer magnetoencephalography atomic spin precessiondetection Larmor precession