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Adaptive control of a Chaotic System with Delay

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Chinese Physics Letters 1998年第7期15卷 477-479页

作者： TIAN Yu-chu National key laboratory of industrial control Technology Institute of Industrial Process ControlZhejiang UniversityHangzhou 310027

A model-reference adaptive control strategy is proposed for a delay chaotic system with known or unknown *** analysis and numerical simulations show that the controlled system state can track an arbitrarily given refe... 详细信息

关键词： parameters chaotic system

An Analysis of Targeted Serum Lipidomics in Patients with Pneumoconiosis—China,2022

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China CDC weekly 2023年第38期5卷 849-855,I0005页

作者： Wenrong Wang Fangda Peng Chunguang Ding Tao Li Huanqiang Wang National Institute of Occupational Health and Poison control Chinese Center for Disease Control and PreventionBeijingChina National Center for Occupational Safety and Health BeijingChina National key laboratory for Engineering control of dust Hazard BeijingChina.

Introduction:Pneumoconiosis emerges as the most critical and prevalent occupational disease in China at present,according to *** indicate that pneumoconiosis may indeed impact the body’s phospholipid ***:In this study,serum samples were taken from 46 paired participants,which included patients with pneumoconiosis and dust-exposed *** employed ultra-performance liquid chromatographytandem mass spectrometry(UPLC-MS/MS)technology in targeted lipidomics to investigate serum target ***,a pilot study was conducted with a selection of 24 pneumoconiosis patients and 24 dust-exposed workers,using both univariate and multivariate statistical analyses to preliminarily identify significant differences in *** to this,the remaining subjects were engaged in a validation study,wherein receiver operating characteristic(ROC)analysis was performed to further substantiate the screening potency of potential lipid biomarkers for ***:The pilot study revealed significantly reduced serum levels of 16∶0 lysophosphatidylcholines(Lyso PC),18∶0–18∶1 phosphatidylglycerol(PG),18∶0–18∶1 phosphatidylethanolamine(PE),18∶0 PE,and 18∶1 lysophosphatidylethanolamine(Lyso PE)in the case group in comparison to the control ***,18∶0 PE,18∶0–18∶1 PE,and 18∶1 Lyso PE emerged as significant phospholipids with superior diagnostic values[area under the curve(AUC)>0.7].A diagnostic model was established,built on 16∶0 PC and 18∶0 PE(AUC>0.8).In the ROC analyses of validation studies,the 18∶0–18∶1 PE and this diagnostic model demonstrated excellent screening efficiency(AUC>0.7).Discussion:A significant divergence in phospholipid metabolism has been observed between pneumoconiosis patients and dust-exposed *** 18∶0–18∶1 PE present in serum could potentially function as a lipid biomarker for ***,diagnostic models were developed relying on 16∶0 PC and 18∶0 PE,proving to have sup

关键词： Lipid metabolism Serum

Variable Universe Fuzzy control for Battery Equalization

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Journal of Systems Science & Complexity 2018年第1期31卷 325-342页

作者： ZHENG Jian CHEN Jian OUYANG Quan The State key laboratory of industrial control Technology College of Control Science and Engineering Zhejiang University

In order to avoid the overcharge and overdischarge damages, and to improve the lifetime of the lithium-ion batteries, it is essential to keep the cell voltages in a battery pack at the same level,i.e., battery equalization. Based on the bi-directional modified Cuk converter, variable universe fuzzy controllers are proposed to adaptively maintain equalizing currents between cells of a serially connected battery pack in varying conditions. The inputs to the fuzzy controller are the voltage differences and the average voltages of adjacent cell pairs. A large voltage difference requires large equalizing current while adjacent cells both with low/high voltages can only stand small discharge/charge currents. Compared with the conventional fuzzy control method, the proposed method differs in that the universe can shrink or expand as the effects of the input changes. This is important as the input may change in a small range. Simulation results demonstrate that the proposed variable universe fuzzy control method has fast equalization speed and good adaptiveness for varying conditions.

关键词： Cell equalization lithium-ion battery variable universe fuzzy control

Reinforcement learning-based cost-sensitive classifier for imbalanced fault classification

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Science China(Information Sciences) 2023年第11期66卷 113-126页

作者： Xinmin ZHANG Saite FAN Zhihuan SONG State key laboratory of industrial control Technology College of Control Science and Engineering Zhejiang University

Fault classification plays a crucial role in the industrial process monitoring domain. In the datasets collected from real-life industrial processes, the data distribution is usually imbalanced. The datasets contain a large amount of normal data(majority) and only a small amount of faulty data(minority); this phenomenon is also known as the imbalanced fault classification problem. To solve the imbalanced fault classification problem, a novel reinforcement learning(RL)-based cost-sensitive classifier(RLCC) based on policy gradient is proposed in this paper. In RLCC, a novel cost-sensitive learning strategy based on policy gradient and the actor-critic of RL is developed. The novel cost-sensitive learning strategy can adaptively learn the cost matrix and dynamically yield the sample weights. In addition, RLCC uses a newly designed reward to train the sample weight learner and classifier using an alternating iterative approach. The alternating iterative approach makes RLCC highly flexible and effective in solving the imbalanced fault classification *** effectiveness and practicability of the proposed RLCC method are verified through its application in a real-world dataset and an industrial process benchmark.

关键词： imbalanced fault classification fault diagnosis industrial process monitoring deep reinforcement learning cost-sensitive learning policy gradient sample weights

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A novel macroscopic traffic model based on generalized optimal velocity model

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Chinese Physics B 2011年第1期20卷 419-425页

作者：周玄昊吕勇哉 State key laboratory of industrial control Technology Institute of Cyber-Systems and ControlZhejiang University

In this paper, we adopt the coarse graining method proposed by Lee H K et al. to develop a macroscopic model from the microscopic traffic model-GOVM. The proposed model inherits the parameter p which considers the influence of next-nearest car introduced in the GOVM model. The simulation results show that the new model is strictly consistent with the former microscopic model. Using this macroscopic model, we can avoid considering the details of each traffic on the road, and build more complex models such as road network model easily in the future.

关键词： macroscopic model microscopic model traffic flow

GEKF,GUKF and GGPF based prediction of chaotic time-series with additive and multiplicative noises

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Chinese Physics B 2008年第9期17卷 3241-3246页

作者：伍雪冬宋执环 State key laboratory of industrial control Technology Department of Control Science and EngineeringZhejiang University

On the assumption that random interruptions in the observation process are modelled by a sequence of independent Bernoulli random variables, this paper generalize the extended Kalman filtering （EKF）, the unscented Kalman filtering （UKF） and the Gaussian particle filtering （GPF） to the case in which there is a positive probability that the observation in each time consists of noise alone and does not contain the chaotic signal （These generalized novel algorithms are referred to as GEKF, GUKF and GGPF correspondingly in this paper）. Using weights and network output of neural networks to constitute state equation and observation equation for chaotic time-series prediction to obtain the linear system state transition equation with continuous update scheme in an online fashion, and the prediction results of chaotic time series represented by the predicted observation value, these proposed novel algorithms are applied to the prediction of Mackey-Glass time-series with additive and multiplicative noises. Simulation results prove that the GGPF provides a relatively better prediction performance in comparison with GEKF and GUKF.

关键词： additive and multiplicative noises different generalized nonlinear filtering chaotic timeseries prediction neural network approximation

Localization of pallets in warehouses using passive RFID system

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Journal of Central South University 2015年第8期22卷 3017-3025页

作者：周俊儒张宏建周洪亮 State key laboratory of industrial control Technology Department of Control Science and EngineeringZhejiang University

Warehouse operation has become a critical activity in supply chain. Position information of pallets is important in warehouse management which can enhance the efficiency of pallets picking and sortation. Radio frequency identification(RFID) has been widely used in warehouse for item identifying. Meanwhile, RFID technology also has great potential for pallets localization which is underutilized in warehouse management. RFID-based checking-in and inventory systems have been applied in warehouse management by many enterprises. Localization approach is studied, which is compatible with existing RFID checking-in and inventory systems. A novel RFID localization approach is proposed for pallets checking-in. Phase variation of nearby tags was utilized to estimate the position of added pallets. A novel inventory localization approach combing angle of arrival(AOA) measurement and received signal strength(RSS) is also proposed for pallets inventory. Experiments were carried out using standard UHF passive RFID system. Experimental results show an acceptable localization accuracy which can satisfy the requirement of warehouse management.

关键词： warehouse management radio frequency identification (RFID) localization tag phase

Indirect Adaptive Robust Trajectory Tracking control of Hard Rock TBM with Load Variation of Tunneling Face

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Chinese Journal of Mechanical Engineering 2019年第2期32卷 168-179页

作者： Chengjun Shao Jianfeng Liao Zhitao Liu Hongye Su State key laboratory of industrial control Technology Institute of Cyber-Systems and Control Zhejiang University State key laboratory of Fluid Power Transmission and control Zhejiang University

Posture adjustment of open-type hard rock tunnel boring machine(TBM) can be achieved by properly adjusting the hydraulic pressure of gripper cylinder and torque cylinders. However, the time-varying inhomogeneous load acting on tunneling face of TBM and complex stratum working condition can cause the trajectory deviation. In this paper,the position and posture rectification kinematics and dynamics models of TBM have been established in order to track the trajectory. Moreover, there are uncertain parameters and uncertain loads from complex working conditions in the dynamic model. An indirect adaptive robust control strategy is applied to achieve precise position and posture trajectory tracking control. Simulation results show when the position deviation only occurs in Y-axis and the current orientation is parallel with the designed axis, the deviation can be corrected by controlling the pressure of gripper cylinder and the actual trajectory meets the designed axis when TBM is pushed forward 0.14 m in X-axis. If the deviation only occurs in Z-axis, then the deviation can be corrected by controlling torque cylinders. If the position deviation occurs both in Y-axis and Z-axis at the same time, the pressure of gripper cylinder and torque cylinders should be controlled at the same time to rectify the deviation. Simulation results are shown to illustrate the e ectiveness and robustness of the proposed controller. This research proposes an indirect adaptive robust controller that can track the planned tracking trajectory smoothly and rapidly.

关键词： Open type hard rock TBM Inhomogeneous load Position and posture rectification Indirect adaptive robust control

Nonlinear fault detection based on locally linear embedding

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控制理论与应用（英文版） 2013年第4期11卷 615-622页

作者： Aimin MIAO Zhihuan SONG Zhiqiang GE Le ZHOU Qiaojun WEN State key laboratory of industrial control Technology Zhejiang University

In this paper, a new nonlinear fault detection technique based on locally linear embedding （LLE） is developed. LLE can efficiently compute the low-dimensional embedding of the data with the local neighborhood structure information preserved. In this method, a data-dependent kernel matrix which can reflect the nonlinear data structure is defined. Based on the kernel matrix, the Nystrrm formula makes the mapping extended to the testing data possible. With the kernel view of the LLE, two monitoring statistics are constructed. Together with the out of sample extensions, LLE is used for nonlinear fault detection. Simulation cases were studied to demonstrate the performance of the proposed method.

关键词： Locally linear embedding Fault detection Nonlinear dimension reduction