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- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2018 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC) - Honolulu, HI (2018.7.18-2018.7.21)] 2018 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC) - Improved Sparse Adaptive Algorithms for Accurate Non-contact Heartbeat Detection Using Time-Window-Variation Technique
摘要： Recently, a sparse adaptive algorithm termed zero-attracting sign least-mean-square (ZA-SLMS), has been clarified to be able to reconstruct robustly heartbeat spectrum by Doppler radar signal. However, since the strengths of noise evidently differ under different body motions, the sparse heartbeat spectra cannot be always acquired accurately by the constant regularization parameter (REPA) that balances the gradient correction and the sparse penalty, applying in the ZA-SLMS algorithm. In this paper, an improved ZA-SLMS algorithm is proposed by introducing adaptive REPA (AREPA), where the proportion of sparse penalty is adjusted based on the standard deviation of radar data. Moreover, to enhance the stability of heartbeat detection, a time-window-variation (TWV) technique is further introduced in the improved ZA-SLMS algorithm, considering the fact that the position of spectral peak associated with the heart rate (HR) is stable when the length of time window changes within a short period. Experimental results measured against five subjects validated that our proposal reliably improves the error of HR estimation than the standard ZA-SLMS algorithm.
关键词： heartbeat detection,time-window-variation,Doppler radar,regularization parameter,sparse adaptive algorithm
更新于2025-09-23 15:23:52
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Antiresonant Reflecting Guidance and Mach-Zender Interference in Cascaded Hollow-Core Fibers for Multi-Parameter Sensing
摘要： We propose and demonstrate a cascaded hollow-core fiber (HCF) device for multi-parameter sensing based on the combination of antiresonant reflecting guidance (ARRG) and Mach-Zender interference (MZI). The device was fabricated by splicing two sections of HCF together. Two sets of fringes, which have different free spectral ranges, were generated from ARRG and MZI, respectively, and were aliasing in the transmission spectrum. The two sets of fringes were then separated using a band pass filter and a Gaussian fitting technique. The wavelengths at two transmission loss dips formed by ARRG and MZI exhibit a temperature sensitivity of 14.1 and 28.5 pm/°C, and a strain sensitivity of 0.4 and ?0.8 pm/με, respectively. By using a crossing matrix with differences sensitivities, the cross-sensitivity between temperature and strain can be solved. The gas pressure response of the cascaded HCF device was also tested up to 300 °C, and linear relationships between the gas pressure sensitivities and temperature were found, which can be used in gas pressure application in various temperatures. Moreover, the proposed cascaded HCF sensor is compact, low cost, and simple for fabrication, and hence offers a promising way for the simultaneous measurement of multiple parameters, such as temperature, strain, and gas pressure.
关键词： multi-parameter sensing,Mach-Zender interference,antiresonant reflecting guidance
更新于2025-09-23 15:22:29
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Deformation Estimation for Time Series InSAR Using Simulated Annealing Algorithm
摘要： Time series interferometric synthetic aperture radar SAR (TSInSAR) is one of the most important surface deformation monitoring techniques, and has been widely used in geodesy. Deformation estimation is one of the main steps of TSInSAR processing, so an effective and efficient algorithm is necessary. Present algorithms have some limitations such as computing costs or errors caused by local extremums. In this work, a novel deformation estimation method based on the simulated annealing (SA) algorithm is proposed to handle this problem. The SA algorithm uses a random search to avoid local extremums and thus can be more likely to get the global optimal solution of deformation. By adopting a better annealing method, this algorithm gets high precision deformation results in less time than most present algorithms. In addition, it can estimate complex nonlinear deformation without adding any computing costs. The results, tested on the real SAR data, confirm the reliability and effectiveness of the SA-based deformation estimation algorithm.
关键词： InSAR,deformation parameter estimation,simulated annealing,TSInSAR
更新于2025-09-23 15:22:29
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[IEEE 2018 OCEANS - MTS/IEEE Kobe Techno-Ocean (OTO) - Kobe, Japan (2018.5.28-2018.5.31)] 2018 OCEANS - MTS/IEEE Kobe Techno-Oceans (OTO) - Parameter Estimation for Rayleigh-Pearson Mixture Model Based on Expectation-Maximization Algorithm
摘要： In this paper I propose a mixture distribution model with Rayleigh and Pearson distributions in order to represent the statistics of the reverberation. In addition the paper studies a parameter estimation method for the mixture distribution. As a preliminary step the parameter estimation of Pearson distribution is studied. Then the method of the parameter estimation is derived in the Rayleigh-Pearson mixture model based on the expectation-maximization (EM) technique. Simulation results have demonstrated that the parameter estimation method provides adequate performance.
关键词： Pearson distribution,parameter estimation,EM algorithm,mixture distribution
更新于2025-09-23 15:22:29
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An Improved DBSCAN Method for LiDAR Data Segmentation with Automatic Eps Estimation
摘要： Point cloud data segmentation, ?ltering, classi?cation, and feature extraction are the main focus of point cloud data processing. DBSCAN (density-based spatial clustering of applications with noise) is capable of detecting arbitrary shapes of clusters in spaces of any dimension, and this method is very suitable for LiDAR (Light Detection and Ranging) data segmentation. The DBSCAN method needs at least two parameters: The minimum number of points minPts, and the searching radius ε. However, the parameter ε is often harder to determine, which hinders the application of the DBSCAN method in point cloud segmentation. Therefore, a segmentation algorithm based on DBSCAN is proposed with a novel automatic parameter ε estimation method—Estimation Method based on the average of k nearest neighbors’ maximum distance—with which parameter ε can be calculated on the intrinsic properties of the point cloud data. The method is based on the ?tting curve of k and the mean maximum distance. The method was evaluated on different types of point cloud data: Airborne, and mobile point cloud data with and without color information. The results show that the accuracy values using ε estimated by the proposed method are 75%, 74%, and 71%, which are higher than those using parameters that are smaller or greater than the estimated one. The results demonstrate that the proposed algorithm can segment different types of LiDAR point clouds with higher accuracy in a robust manner. The algorithm can be applied to airborne and mobile LiDAR point cloud data processing systems, which can reduce manual work and improve the automation of data processing.
关键词： parameter estimation,segmentation,DBSCAN,LiDAR
更新于2025-09-23 15:22:29
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Adaptive Fuzzy Sliding Mode Command-Filtered Backstepping Control for Islanded PV Microgrid with Energy Storage System
摘要： This study focuses on the control of islanded photovoltaic (PV) microgrid and design of a controller for PV system. Because the system operates in islanded mode, the reference voltage and frequency of AC bus are provided by the energy storage system. We mainly designed the controller for PV system in this study, and the control objective is to control the DC bus voltage and output current of PV system. First, a mathematical model of the PV system was set up. In the design of PV system controller, command-filtered backstepping control method was used to construct the virtual controller, and the final controller was designed by using sliding mode control. Considering the uncertainty of circuit parameters in the mathematical model and the unmodeled part of PV system, we have integrated adaptive control in the controller to achieve the on-line identification of component parameters of PV system. Moreover, fuzzy control was used to approximate the unmodeled part of the system. In addition, the projection operator guarantees the boundedness of adaptive estimation. Finally, the control effect of designed controller was verified by MATLAB/Simulink software. By comparing with the control results of proportion-integral (PI) and other controllers, the advanced design of controller was verified.
关键词： islanded operation mode,Photovoltaic (PV),sliding mode,parameter adaptive,fuzzy control,command-filter backstepping
更新于2025-09-23 15:22:29
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Simultaneous measurement of temperature and refractive index based on microfiber Bragg Grating in Sagnac loop
摘要： In this paper, a simultaneous measurement system of temperature and refractive index (RI) is proposed and demonstrated. The dips in the output spectrum of the proposed sensor are formed by the micro?ber Bragg Grating (mFBG) and Sagnac loop. Due to di?erent interference mechanisms, the dual-parameter measurement is realized by mFBG and Sagnac loop with di?erent sensitivities to temperature and RI. Compared with the traditional Sagnac loop sensors, the proposed Sagnac loop with mFBG is much sensitive to surrounding RI. The results show that the temperature sensitivity is 0.033 nm/°C and ?0.015 dB/°C. And the RI sensitivity is 39.30 nm/RIU and 41.51 dB/RIU. The proposed sensor has a simple structure and great potential in biological and chemical ?elds.
关键词： Micro?ber Bragg Grating,Sagnac loop,Dual-parameter measurement
更新于2025-09-23 15:22:29
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[IEEE 2018 7th International Conference on Agro-geoinformatics (Agro-geoinformatics) - Hangzhou (2018.8.6-2018.8.9)] 2018 7th International Conference on Agro-geoinformatics (Agro-geoinformatics) - Using Stochastic Programming and Remote Sensing to Implement Ecological Restoration of Degraded Mud Flat Ecosystem
摘要： This paper presents an interval-parameter stochastic programming (ISP) approach for supporting ecological restoration of degraded mud flat ecosystem under mud flat ecological restoration cost uncertainties. ISP is capable of performing mud flat ecological system analysis, ecological restoration cost uncertainty analysis, and solution block screening in a comprehensive and systematic way. A mud flat ecological restoration problem is used to demonstrate the applicability of the proposed ISP approach. The results indicate that solution block can be generated for the objective function and decision variables, and a variety of decision alternatives of solution block can be obtained under different cost uncertainty scenarios.
关键词： interval-parameter stochastic programming,ecological restoration,return on investment,degraded mud flat ecosystem,sensors,satellite
更新于2025-09-23 15:22:29
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Determining Series Resistance for Equivalent Circuit Models of a PV Module
摘要： Literature describes various methods for determining a series resistance for a photovoltaic device from measured IV curves. We investigate use of these techniques to estimate the series resistance parameter for a single diode equivalent circuit model. With simulated IV curves we demonstrate that the series resistance values obtained by these techniques differ systematically from the known series resistance parameter values used to generate the curves, indicating that these methods are not suitable for determining the series resistance parameter for the single diode model equation. We present an alternative method to determine the series resistance parameter jointly with the other parameters for the single diode model equation, and demonstrate the accuracy and reliability of this technique in the presence of measurement errors.
关键词： Current-voltage characteristics,parameter extraction,electric resistance,solar panels
更新于2025-09-23 15:22:29
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[IEEE 2018 International Conference on Intelligent and Advanced System (ICIAS) - Kuala Lumpur, Malaysia (2018.8.13-2018.8.14)] 2018 International Conference on Intelligent and Advanced System (ICIAS) - Simulation of Interdigitated Electrodes (IDEs) Geometry Using COMSOL Multiphysics
摘要： Interdigitated Electrodes (IDEs) based sensor in comb-like electrodes structure is also an attractive candidate in gas sensor and biosensor applications, owing to its simple structural design. The sensitivity can be improved based on geometric parameters of the sensor. Hence, in this paper, we study the physical model of the IDEs-based sensor and concern with its geometrical parameters (gap sizes, number of fingers and width of fingers) based on the finite element simulations using COMSOL Multiphysics. The simulation results were used to show the electrical field that generated by the IDEs and compare to other to find the optimum design. Based on the results, the relationship between the geometric parameters and the IDEs performances are studied. The simulation results show that the higher electric fields are generated with the smaller gap size and smaller width of fingers. Besides that, the results show that the gap size and the width of fingers affect the IDEs performance significantly compared to the number of fingers. The IDE with the design 18 fingers, 0.1 mm gap size between fingers and 0.1 mm width of the finger is the optimum design which generates 30.6 kV/m average of electric field magnitude.
关键词： IDEs,COMSOL Multiphysics,geometry parameter
更新于2025-09-23 15:22:29