- 标题
- 摘要
- 关键词
- 实验方案
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Automatic Detection of Driver Impairment Based on Pupillary Light Reflex
摘要： The main objective of this paper is to determine the feasibility of designing a driver drunkenness detection system based on the dynamic analysis of a subject’s pupillary light reflex (PLR). This involuntary reaction is widely utilized in the medical field to diagnose a variety of diseases, and in this paper, the effectiveness of such a method to reveal an impairment condition due to alcohol abuse is evaluated. The test method consists in applying a light stimulus to one eye of the subject and to capture the dynamics of constriction of both eyes; for extracting the pupil size profiles from the video sequences, a two-step methodology is described, where in the first phase, the iris/pupil search within the image is performed, and in the second stage, the image is cropped to perform pupil detection on a smaller image to improve time efficiency. The undesired pupil dynamics arising in the PLR are defined and evaluated; a spontaneous oscillation of the pupil diameter is observed in the range [0, 2] Hz and the accommodation reflex causes pupil constriction of about 10% of the iris diameter. A database of pupillary light responses is acquired on different subjects in baseline condition and after alcohol consumption, and for each one, a first-order model is identified. A set of features is introduced to compare the two populations of responses and is used to design a support vector machine classifier to discriminate between “Sober” and “Drunk” states.
关键词： pupil dynamics,video processing,system identification,ADAS,support vector machine,classification
更新于2025-09-23 15:21:21
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Real-Time MPPT Optimization of PV Systems by Means of DCD-RLS Based Identification
摘要： Maximum power point tracking (MPPT) algorithms continuously change duty cycle of a power converter to extract maximum power from photovoltaic (PV) panels. In all of MPPT methods, two parameters, i.e. perturbation period (Tp) and amplitude (ΔD) have a great effect on speed and accuracy of MPPT. Optimum value of the perturbation period is equal to the system settling time which is the system model-dependent parameter. Since the system model varies according to the change of irradiance level and temperature, the value of Tp has to be determined online. In this paper, the parametric identification method is adopted to identify the online value of Tp. The proposed method is based on the dichotomous coordinate descent-recursive least squares (DCD-RLS) algorithm and uses an infinite impulse response (IIR) adaptive filter as the system model. Computation of this algorithm is based on an efficient, fixed-point, and iterative approach with no explicit division operations; these features are highly suitable for online applications. As a result, the proposed method compared to previous works leads to more accurate and faster identification of the system settling time. In order to test and validate the proposed method, it has been simulated and implemented to be further validated with experimental data.
关键词： Photovoltaic Systems,Perturbation Period,Recursive Least Squares (RLS),Dichotomous Coordinate Descent (DCD),Maximum Power Point Tracking (MPPT),System Identification
更新于2025-09-23 15:21:21
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Estimation of damage thickness in fibre-reinforced composites using pulsed thermography
摘要： Non-destructive-testing (NDT), including active thermography, has become an inevitable part of composite process and product verification, post-manufacturing. However, there is no reliable NDT technique available to ensure the interlaminar bond integrity during laminates integration, bonding or repair where the presence of thin airgaps in the interface of dissimilar polymer composite materials would be detrimental to structural integrity. This paper introduces a novel approach attempting to quantify the damage thickness of composites (the thickness of air gaps inside composites) through a single-side inspection of pulsed thermography. The potential of this method is demonstrated by testing on three specimens with different types of defect, where the Pearson Correlation Coefficients of the thickness estimation for block defects and flat-bottom holes are 0.75 and 0.85, respectively. This approach will considerably enhance the degradation assessment performance of active thermography by extending damage measurement from currently two dimensions to three dimensions, and become an enabling technology on quality assurance of structural integrity.
关键词： Active thermography,system identification,bonded repair,nonlinear correlation analysis,composite damage detection
更新于2025-09-23 15:21:01
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[IEEE 2019 Compound Semiconductor Week (CSW) - Nara, Japan (2019.5.19-2019.5.23)] 2019 Compound Semiconductor Week (CSW) - Low Noise Monolithically Integrated Membrane DFB Laser on Silicon
摘要： The dynamic characteristic of an autonomous underwater vehicle (AUV) is affected when it is reconfigured with different payloads. It is desirable to have an updated model, such that the control and guidance law can be redesigned to obtain better performance. Hence, we develop a method to enable online identification of AUV dynamics via in-field experiments, where the AUV is commanded to execute a compact set of maneuvers under doublet excitation. The identification process has two stages. In the training stage, state variable filter and recursive least square (SVF-RLS) estimator is used to estimate the unknown parameters. In the validation stage, the prediction capability of the model is checked using a fresh data set. The parameters converged within 12 s in the experiments using five different thrusts. Validation results show that the identified models are able to explain 78% to 92% of the output variation. Next, we compare the SVF-RLS estimator with the conventional offline identification method. The comparison shows that the SVF-RLS estimator is better in terms of prediction accuracy, computational cost and training time. The usefulness of the identified models is highlighted in two applications. We use it to estimate the turning radius of the AUV at different speeds, and to design a gain-scheduled controller.
关键词： system identification,Autonomous underwater vehicles (AUV)
更新于2025-09-23 15:19:57
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[IEEE 2019 21st International Middle East Power Systems Conference (MEPCON) - Cairo, Egypt (2019.12.17-2019.12.19)] 2019 21st International Middle East Power Systems Conference (MEPCON) - Optimization of Voltage Source Invertera??s Controllers Using Salp Swarm Algorithm in Grid Connected Photovoltaic System
摘要： The dynamic characteristic of an autonomous underwater vehicle (AUV) is affected when it is reconfigured with different payloads. It is desirable to have an updated model, such that the control and guidance law can be redesigned to obtain better performance. Hence, we develop a method to enable online identification of AUV dynamics via in-field experiments, where the AUV is commanded to execute a compact set of maneuvers under doublet excitation. The identification process has two stages. In the training stage, state variable filter and recursive least square (SVF-RLS) estimator is used to estimate the unknown parameters. In the validation stage, the prediction capability of the model is checked using a fresh data set. The parameters converged within 12 s in the experiments using five different thrusts. Validation results show that the identified models are able to explain 78% to 92% of the output variation. Next, we compare the SVF-RLS estimator with the conventional offline identification method. The comparison shows that the SVF-RLS estimator is better in terms of prediction accuracy, computational cost and training time. The usefulness of the identified models is highlighted in two applications. We use it to estimate the turning radius of the AUV at different speeds, and to design a gain-scheduled controller.
关键词： Autonomous underwater vehicles (AUV),system identification
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Sozopol, Bulgaria (2019.9.6-2019.9.8)] 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Influence of Measurements Uncertainty on Uncertainty of Gilbert-Huang Transform Modes
摘要： The approach to simplifying the identification of a system using the input and output non-stationary or stationary processes is proposed in the article. The realizations of the process (input and output signals) are converted to the sum of individual components (modes) based on the Hilbert-Huang transform, and then the corresponding modes of this transformation are used for the virtual subsystem identification. The identification quality depends on the measurement uncertainty of both the signal and its Hilbert-Huang modes. The influence of measurements uncertainty of the signal on the individual modes’ uncertainty, considering important factors, is analyzed in the article. The obtained results extend the conditions for solving the problems of system identification.
关键词： measurements uncertainty,system identification,Hilbert-Huang transform
更新于2025-09-19 17:13:59
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[IEEE 2019 13th International Conference on Software, Knowledge, Information Management and Applications (SKIMA) - Island of Ulkulhas, Maldives (2019.8.26-2019.8.28)] 2019 13th International Conference on Software, Knowledge, Information Management and Applications (SKIMA) - Real-Time Video Dehazing for Industrial Image Processing
摘要： The dynamic characteristic of an autonomous underwater vehicle (AUV) is affected when it is reconfigured with different payloads. It is desirable to have an updated model, such that the control and guidance law can be redesigned to obtain better performance. Hence, we develop a method to enable online identification of AUV dynamics via in-field experiments, where the AUV is commanded to execute a compact set of maneuvers under doublet excitation. The identification process has two stages. In the training stage, state variable filter and recursive least square (SVF-RLS) estimator is used to estimate the unknown parameters. In the validation stage, the prediction capability of the model is checked using a fresh data set. The parameters converged within 12 s in the experiments using five different thrusts. Validation results show that the identified models are able to explain 78% to 92% of the output variation. Next, we compare the SVF-RLS estimator with the conventional offline identification method. The comparison shows that the SVF-RLS estimator is better in terms of prediction accuracy, computational cost and training time. The usefulness of the identified models is highlighted in two applications. We use it to estimate the turning radius of the AUV at different speeds, and to design a gain-scheduled controller.
关键词： system identification,Autonomous underwater vehicles (AUV)
更新于2025-09-19 17:13:59
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Techniques to Investigate the Application of Cold Spray in Fabrication of Nanoplasmonic films: Parameter Identification
摘要： The decomposition of a complex system allows identification of its interacting variables. In this article the coupling between the Cold Spray (CS) thin film fabrication and functional properties in Surface Plasmon Polaritons (SPP) are investigated with a view to optimise the CS fabrication process in nano thin films. There are many reported advantages of the cold gas spray over other thermal spray technologies. However the fabrication of thin films by cold gas is limited on the capability of the transport system. This study is meant on finding ways to improve the cold gas spray for deposition of nano particles. In particular, the deposition of plasmonics nano particles for functional films in the nano scale regime. Since the requirements for each film application are different, this study is specifically targeted at films used in biosensor technology with a focus on the plasmonics sensor that use gold or silver nano particles. The paper gives the details of the parameter identification process that was used to determine missing links between the cold spray process and the optical functional thin film characteristics. In the preliminary study, intuitively, the systems engineering and pattern recognition techniques were used to explore the most probable driving variables for the cold gas coating process in functional films. This process determines the deposition parameters that characterize the surface roughness, interface roughness and film thickness as would be required for functional thin films. We have since designed a systematic numerical process for the iterations towards this direction. This study opens new avenues for further research and advancement of the cold gas spray method in nano thin film.
关键词： cold spray applications,Multiple Particle Impact,system identification,plasmonics thin films
更新于2025-09-12 10:27:22
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Genetic Algorithm–Genetic Programming Approach to Identify Hierarchical Models for Ultraviolet Disinfection Reactors
摘要： The performance of ultraviolet (UV) disinfection reactors using experimental data poses major challenges to the water treatment industry, and a regression model has been developed in the water treatment industry to predict UV reactor performance. Genetic programming (GP) can be applied using a process of symbolic regression to create empirical models of data describing a process or system. While classical regression analysis specifies the model structure a priori, GP automatically evolves both the structure and numeric coefficients of the model. GP-derived equations are often computationally complex, however, and do not generalize well for new data sets. This research develops a new model identification procedure that simultaneously identifies an equation to describe a system and hierarchical parameters that are fit for separate data sets. A coupled genetic algorithm (GA) and genetic programming approach (GA-GP) is developed to search for the best-fitting model structure and hierarchical parameter values. Modifications were made to the GA-GP approach to reduce model error while limiting the growth of complex tree structures. The GA-GP method is applied here to identify models for multiple UV reactors by training a model for three data sets. The GA-GP method identified a model with lower error across multiple data sets compared to GP alone, linear regression, and the industry regression model. Including hierarchical terms allowed the search to identify a model that generalizes across multiple data sets.
关键词： System identification,Drinking water treatment,Evolutionary computation,Bloat,Symbolic regression
更新于2025-09-04 15:30:14