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Intelligent Communication, Sensing and Electromagnetics (ICSE), International Conference on

作者： Heng Du Huaiming Cang Yiwen Bai Xinyi Wang Beijing Elephant Technology Co. Ltd Beijing China School of Transportation Science and Engineering Beihang University Beijing China The State Key Lab of Intelligent Transportation System Beijing China Tianjin Key Laboratory for Advanced Mechanical System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education (Tianjin University of Technology) Tianjin China

ISBN: (数字)9798350354935

ISBN: (纸本)9798350354942

In the field of railway transportation, with the continuous improvement of train running speed and the continuous increase of operating mileage, it becomes particularly important to ensure the safety and integrity of small-target infrastructure along the railway train. Although many small-target detection methods have been proposed, the research on small-target infrastructure detection along rail trains is very rare. To solve this problem, this paper proposes a small-target infrastructure detection network with spatial tracking and multi-level feature extraction based on Yolov8n. The experimental results show that ST-YOLO has a 3.6% mAP improvement on the OSDaR23 dataset compared to the baseline Yolov8n, and shows significant advantages over other state-of-the-art methods.

关键词： Rails Transportation Railway safety Switches Feature extraction Rail transportation Real-time systems Sensors Safety Monitoring

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Adaptive Sliding Mode control for a Blower-Based Breathing Simulator with Unknown and Time-Varying Airway Resistance and Compliance

Adaptive Sliding Mode Control for a Blower-Based Breathing S...

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International Conference on engineering and Emerging Technologies (ICEET)

作者： Trung Dat Phan Ly Xuan Truong Pham Cong Toai Truong Van Tu Duong Huy Hung Nguyen Key Laboratory of Digital Control and System Engineering (DCSELab) Faculty of Mechanical Engineering Ho Chi Minh City University of Technology (HCMUT) Ho Chi Minh City Vietnam Vietnam National University Ho Chi Minh City Ho Chi Minh City Vietnam Faculty of Electronics and Telecommunication Saigon University Ho Chi Minh City Vietnam

ISBN: (数字)9798331532895

ISBN: (纸本)9798331532901

Looking back at history, the world has experienced many pandemics that affect the people experiencing respiratory system, and most recently, the severe devastation of the COVID-19 pandemic. This reflects the reality of life and the global disparity in ventilator availability between high-income countries and low and middle-income countries. Additionally, various simple ventilators and breathing simulators are non-functional with various artificial lungs due to dynamic lung parameter changes during operation. Therefore, this paper proposes an adaptive controller for a novel blower-based breathing simulator to address the challenge of unknown and varying artificial lung parameters. Specifically, an adaptive sliding mode controller has been developed for precise volume control under uncertain conditions. Alongside that, the metric Integral of Absolute Error (IAE) is used to evaluate control performance. The first simulation scenario with three different input signals, which comprise a ramp, parabolic, and sinusoidal, remained permissible errors below 5%. In the other scenario, the blower-based breathing simulator model's control performance with two different airway parameters sets IAE values over 12 cycles. In the 6 initial cycles, the trend of IAE values shows a gradual decrease over cycles. At cycle 7, a change in airway parameters causes a difference in the IAE value, but it quickly decreases in the following cycles. As indicated by this outcome, the proposed controller proves not only efficient when the airway parameters are unknown constants but also adaptable when these parameters change over time.

关键词： Resistance Measurement Ventilators Pandemics Lungs Simulation Pulmonary diseases Market research History Sliding mode control

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Recursive Least Squares Algorithm for Online Parameter Identification of DC Motor: Theory and Practice

Recursive Least Squares Algorithm for Online Parameter Ident...

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International Conference on engineering and Emerging Technologies (ICEET)

作者： Nhut Thang Le Minh Tri Nguyen Cong Toai Truong Van Tu Duong Huy Hung Nguyen Key Laboratory of Digital Control and System Engineering (DCSELab) Faculty of Mechanical Engineering Ho Chi Minh City University of Technology (HCMUT) Ho Chi Minh City Vietnam Vietnam National University Ho Chi Minh City Ho Chi Minh City Vietnam Faculty of Electronics and Telecommunication Saigon University Ho Chi Minh City Vietnam

ISBN: (数字)9798331532895

ISBN: (纸本)9798331532901

In the automation era, DC motors are widely utilized across various industries due to their adaptability and efficiency. In the downside of reality, accurately modelling and controlling their behavior under diverse operational conditions remains challenging. Hence, this study proposes a comprehensive approach integrating Recursive Least Squares (RLS) for parameter estimation within ARX models, combined with experiment data to enhance model accuracy. Moreover, State Feedback control is applied to optimize DC motor operation. Specifically, the model coefficients are predicted over time, alongside recording the error between the actual output and predicted output within a 30 -second timeframe. The results indicate that the error is controlled and converges to 0 within 0.5-second (approximately 10 cycles). As a result, in the online model updates, system error increases and deviates from zero over time due to model drift, likely caused by environmental factors or changes in the motor's temperature. In contrast, the error remains stabilized around zero with online model updates, demonstrating improved control effectiveness through continuous model adaptation.

关键词： Adaptation models State feedback Solid modeling Parameter estimation Temperature Wheels Predictive models DC motors Solids Data models

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Modeling and control of Testing Machine for Fire Sprinkler K - Factor Evaluation

Modeling and Control of Testing Machine for Fire Sprinkler K...

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International Conference on control, Automation and Information Sciences (ICCAIS)

作者： Hai Dang Ho Huu Nhan Nguyen Cong Toai Truong Van Tu Duong Huy Hung Nguyen National Key Laboratory of Digital Control and System Engineering (DCSELab) Faculty of Mechanical Engineering Ho Chi Minh City University of Technology (HCMUT) Ho Chi Minh City Vietnam Vietnam National University Ho Chi Minh City Linh Trung Ward Thu Duc City Ho Chi Minh City Vietnam Faculty of Electronics and Telecommunication Saigon University Ho Chi Minh City Vietnam

ISBN: (数字)9798331542047

ISBN: (纸本)9798331542054

During the period of demographic transition, when the demand for accommodation increases, the role of the fire protection system becomes more important than ever. Among these, the most popular fire protection component is the fire sprinkler. To ensure the safety requirements, this paper introduces the evaluation $K$ -factor machine (EKFM) to test fire sprinklers according to the ISO 6182–1: 2004 standard. Overall, the EKFM comprises a water pump whose speed is adjusted by a variable frequency drive (VFD) to control pipeline flow and sensor system, including flow and pressure sensor to provide feedback on the value measure. Additionally, according to the ISO 6182–1: 2004 standard, the operation of the EKFM needs to create an initial pressure of 0.5 bar in the pipeline, increase by 1 bar per pressure set point until reaching 6. 5 bar, and then decrease back to 0.5 bar. Based on the properties of EKFM, the paper proposes model identification of the EKFM and designs the P controller to ensure the steady-state error is within 5 % of the setpoint for each pressure step. Specifically, the EKFM is modeled identification using a data-driven approach, comprising group one data for identification and another for validation. Besides, simulation scenarios are conducted following the ISO 6182–1: 2004 standard test procedure to find the suitable value for proportional (P) control and compare the simulation result with controller evaluation criteria. Furthermore, experimental data indicate that the EKFM can maintain an error of within 5 % error for pressures less than 3 bar and 2 % for pressures greater than 3 bar. As a result, the EKFM can evaluate the quality of the fire sprinkler before it is applied in the market.

关键词： ISO Standards Simulation Pipelines Variable speed drives Water pumps Steady-state Protection Standards Bars Testing

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Investigation on surface integrity in laser-assisted machining of Inconel 718 based on in-situ observation

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Procedia CIRP 2022年 108卷 129-134页

作者： Hang Zhang Rong Yan Ben Deng Jieyu Lin Minghui Yang Fangyu Peng National NC System Engineering Research Center School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China State Key Lab of Digital Manufacturing Equipment and Technology School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

Inconel 718, a nickel-based superalloy, is widely used in the key parts of aero-engine owing to its high performance at elevated temperatures. Meanwhile, Inconel 718 is a typical difficult-to-cut material which is hard to obtain ideal surface integrity by conventional machining (CM). Laser-assisted machining (LAM) has a good potential to improve the machinability. In order to study the processing mechanism in the LAM of Inconel 718, the in-situ and ex-situ studies were presented in this paper. In the in-situ analysis, LAM and CM experiments were carried out based on in-situ observation and digital image correlation (DIC) technology. The Von Mises strain and equivalent plastic strain rate in the primary shear zone (PSZ) and cutting force were measured. According to the DIC results, under the experimental conditions of this paper, the average Von Mises strain and average equivalent plastic strain rate of PSZ in LAM increase by about 10% and 20% respectively due to the softening of Inconel 718 by laser heating, compared with CM. In-situ analysis shows that Inconel 718 in LAM is more prone to plastic flow, resulting in lower cutting forces. As for the ex-situ characterization, the surface roughness, residual stress and tool wear were measured. The measured results show that LAM can significantly reduce surface roughness and tool wear, and cause compressive residual stress on the machined surface.

关键词： Laser-assisted machining surface integrity in-situ observation Inconel 718

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On the Gaussian Filtering for Nonlinear Dynamic systems Using Variational Inference

On the Gaussian Filtering for Nonlinear Dynamic Systems Usin...

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International Conference on Information Fusion

作者： Yi Liu Xi Li Le Yang Lyudmila Mihaylova Ji Li Department of Electrical and Computer Engineering University of Canterbury Christchurch NZ State Key Lab of Complex Electromagnetic Environment Effects on Electronics and Information Systems National University of Defense Technology Changsha China Department of Automatic Control and System Engineering University of Sheffield Sheffield UK Locaris Electronic Technology Co. Ltd Zhengzhou China

ISBN: (数字)9781737749769

ISBN: (纸本)9798350371420

This paper introduces a new variational Gaussian filtering approach for estimating the state of a nonlinear dynamic system. We first assume that the predictive distribution of the state is Gaussian and derive an iterative method for updating the state posterior in the natural parameter space through KullbackLeibler divergence minimization. The obtained update rule is the same as that of the conjugate-computation variational inference technique in Bayesian learning. The derivation here is simpler and more insightful. We then impose a Wishart prior on the inverse of the state prediction covariance to take into account the impact of approximating the state predictive distribution using a Gaussian density on the state posterior estimation. The prediction covariance is identified jointly with the state using variational inference and the established state posterior update rule to achieve the desired Gaussian filtering. Simulation study examines the performance of the proposed filtering framework in target tracking based on bearing and range measurements.

关键词： Target tracking Smoothing methods Filtering Estimation Filtering algorithms Prediction algorithms Minimization Nonlinear dynamical systems Bayes methods Iterative methods

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Predictor-Based Constrained Fixed-Time Sliding Mode control of Multi-Uav Formation Flight

SSRN

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SSRN 2024年

作者： Khodaverdian, Maria Hajshirmohamadi, Shahram Hakobyan, Aleksandr Ijaz, Salman Center for Scientific Innovation and Education Aerial Robotics Laboratory of National Polytechnic University of Armenia Yerevan Armenia Department of Electrical and Computer Engineering Isfahan University of Technology Isfahan84156-83111 Iran Key Laboratory of More Electric Aircraft and Control System Lab University of Nottingham Ningbo China

In this work, a predictor-based fixed-time sliding mode control is designed to tackle the problem of achieving precise trajectory tracking control of multiple unmanned aerial vehicles formation flight. The proposed approach simultaneously addresses various practical requirements, such as optimality, constraints, fixed-time convergence, external interferences, and computational ***, a constrained performance index is constructed based on the prediction of the fixed-time sliding surface, the reaching law, and the control input. Secondly, optimal control input is calculated by solving the constrained quadratic optimization problem. An outstanding feature of this study is the theoretical guarantee of closed-loop system stability in the presence of external disturbances and ***, the comparative evaluation with sliding mode predictive control law and fixed-time sliding mode control methods demonstrates that the proposed approach achieves a straightforward control method with improved performance and acceptable accuracy. Finally, a test is conducted to demonstrate the algorithm's potential for hardware implementation by employing Hardware-in-the-Loop (HIL) test. © 2024, The Authors. All rights reserved.

关键词： Sliding mode control

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On the Approximation of the Quotient of Two Gaussian Densities for Multiple-Model Smoothing

On the Approximation of the Quotient of Two Gaussian Densiti...

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International Conference on Information Fusion

作者： Yi Liu Xi Li Le Yang Lyudmila Mihaylova Yanbo Xue Department of Electrical and Computer Engineering University of Canterbury Christchurch NZ State Key Lab of Complex Electromagnetic Environment Effects on Electronics and Information Systems National University of Defense Technology Changsha China Department of Automatic Control and System Engineering University of Sheffield Sheffield UK Career Science Lab Beijing China

The quotient of two multivariate Gaussian densities can be written as an unnormalized Gaussian density, which has been applied in some recently developed multiple-model fixed-interval smoothing algorithms. However, this expression is invalid if instead of being positive definite, the covariance of the unnormalized Gaussian density is indefinite (i.e., it has both positive and negative eigenvalues) or undefined (i.e., computing it requires inverting a singular matrix). This paper considers approximating the quotient of two Gaussian densities in this case using two different approaches to mitigate the caused numerical problems. The first approach directly replaces the indefinite covariance of the unnormalized Gaussian density with a positive definite matrix nearest to it. The second approach computes the approximation through solving, using the natural gradient, an optimization problem with a Kullback-Leibler divergence-based cost function. This paper illustrates the application of the theoretical results by incorporating them into an existing smoothing method for jump Markov systems and utilizing the obtained smoothers to track a maneuvering target.

关键词：

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Bridging the structure gap between pellets in artificial dissolution media and in gastro-intestinal tract in rats

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Acta Pharmaceutica Sinica B 2022年第1期12卷 326-338页

作者： Hongyu Sun Siyu He Li Wu Zeying Cao Xian Sun Mingwei Xu Shan Lu Mingdi Xu Baoming Ning Huimin Sun Tiqiao Xiao Peter York Xu Xu Xianzhen Yin Jiwen Zhang School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai 201418China Center for Drug Delivery System Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China School of Materials Science and Engineering Center for Supramolecular Chemistry and CatalysisDepartment of ChemistryShanghai UniversityShanghai 200444China NMPA Key Laboratory for Quality Research and Evaluation of Pharmaceutical Excipients National Institutes for Food and Drug ControlBeijing 100050China National Institutes for Food and Drug Control Beijing 100050China Shanghai Synchrotron Radiation Facility/Zhangjiang Lab Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Center for MOST and Image Fusion Analysis Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201210China

Changes in structure of oral solid dosage forms(OSDF) elementally determine the drug release and its therapeutic *** this research,synchrotron radiation X-ray micro-computed tomography was utilized to visualize the 3 D structure of enteric coated pellets recovered from the gastrointestinal tract of *** structures of pellets in solid state and in vitro compendium media were *** in vivo underwent morphological and structural changes which differed significantly from those in vitro compendium ***,optimizations of the dissolution media were performed to mimic the appropriate in vivo conditions by introducing pepsin and glass microspheres in *** sphericity,pellet volume,pore volume and porosity of the in vivo esomeprazole magnesium pellets in stomach for2 h were recorded 0.47,1.55 × 10^(8)μm^(3),0.44 × 10^(8)μm^(3)and 27.6%,*** adding pepsin and glass microspheres,the above parameters in vitro reached to 0.44,1.64 × 10^(8)μm^(3)0.38 × 10^(8)μm^(3)and 23.0%,*** magnesium pellets behaved *** structural features of pellets between in vitro media and in vivo condition were bridged successfully in terms of 3 D structures to ensure better design,characterization and quality control of advanced OSDF.

关键词： Internal 3D structure 3D reconstruction Structural parameter Enteric coated pellets Synchrotron radiation X-ray micro computed tomography In vivo and in vitro structure correlation Esomeprazole magnesium Omeprazole magnesium

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Model Predictive control with Reach-avoid Analysis

arXiv

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arXiv 2023年

作者： Ren, Dejin Lu, Wanli Lv, Jidong Zhang, Lijun Xue, Bai State Key Lab. of Computer Science Institute of Software CAS Beijing China University of Chinese Academy of Sciences Beijing China National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University Beijing China

In this paper we investigate the optimal controller synthesis problem, so that the system under the controller can reach a specified target set while satisfying given constraints. Existing model predictive control (MPC) methods learn from a set of discrete states visited by previous (sub-)optimized trajectories and thus result in computationally expensive mixed-integer nonlinear optimization. In this paper a novel MPC method is proposed based on reach-avoid analysis to solve the controller synthesis problem iteratively. The reach-avoid analysis is concerned with computing a reach-avoid set which is a set of initial states such that the system can reach the target set successfully. It not only provides terminal constraints, which ensure feasibility of MPC, but also expands discrete states in existing methods into a continuous set (i.e., reach-avoid sets) and thus leads to nonlinear optimization which is more computationally tractable online due to the absence of integer variables. Finally, we evaluate the proposed method and make comparisons with state-of-the-art ones based on several examples. Copyright © 2023, The Authors. All rights reserved.

关键词： Model predictive control

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