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- 2019
- Distributed optical fiber sensing
- Optical frequency domain reflection
- Polynomial regression algorithm
- Nonlinear tuning compensation
- Optoelectronic Information Science and Engineering
- Hebei University of Technology
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[IEEE 2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall) - Xiamen, China (2019.12.17-2019.12.20)] 2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall) - Efficient Characterization of Topological Photonics Using the Broadband Greena??s Function
摘要： A novel method is developed in this paper to characterize the band diagram and modal ?elds of gyromagnetic photonic crystals that support topolgoical one-way edge states. We exploy an integral equation based method that utilizes the broadband Green’s function as the kernel. The broadband Green’s function is a hybrid representation of the periodic lattice Green’s function that includes an imaginary wavenumber component represented in exponentially decaying spatial series and a reminder in fast converging Floquet plane wave expansions. Special boundary conditions govern the ?elds across the interface of the gyromagnetic scatterers, leading to surface integral equations (SIEs) that involve three components including the pilot ?eld, its normal derivative and its tangential derivative. To reduce the independent number of unknowns, roof-top basis functions and the Garlerkin’s method are used to discretize the SIEs into matrix equations. The broadband Green’s function allows converting the discretized SIEs into a linear eigenvalue problem of a small size. The eigenvalues and eigenvectors of the linear eigenvalue problem are directly related to the band solutions and modal ?elds of the photonic crystal. The proposed approach is an e?ective method to characterize wave interactions with periodic scatterers using integral equations. The solutions of the presented approach are compared against Comsol simulations for various cases to show its accuracy and e?ciency.
关键词： topological photonics,surface integral equations,broadband Green’s function,linear eigenvalue problem,gyromagnetic photonic crystals
更新于2025-09-23 15:21:01
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Identification of heavy metal-contaminated Tegillarca granosa using laser-induced breakdown spectroscopy and linear regression for classification
摘要： Tegillarca granosa (T. granosa) is susceptible to heavy metals, which may pose a threat to consumer health. Thus, healthy and polluted T. granosa should be distinguished quickly. This study aimed to rapidly identify heavy metal pollution by using laser-induced breakdown spectrometry (LIBS) coupled with linear regression classification (LRC). Five types of T. granosa were studied, namely, Cd-, Zn-, Pb-contaminated, mixed contaminated, and control samples. Threshold method was applied to extract the significant variables from LIBS spectra. Then, LRC was used to classify the different types of T. granosa. Other classification models and feature selection methods were used for comparison. LRC was the best model, achieving an accuracy of 90.67%. Results indicated that LIBS combined with LRC is effective and feasible for T. granosa heavy metal detection.
关键词： laser-induced breakdown spectrometry,shellfish,linear regression classification,heavy metal
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) - Growth of InGaAs solar cells on InP(001) miscut substrates using solid-source molecular beam epitaxy
摘要： In this paper, we present a new motor imagery classification method in the context of electroencephalography (EEG)-based brain–computer interface (BCI). This method uses a signal-dependent orthogonal transform, referred to as linear prediction singular value decomposition (LP-SVD), for feature extraction. The transform defines the mapping as the left singular vectors of the LP coefficient filter impulse response matrix. Using a logistic tree-based model classifier; the extracted features are classified into one of four motor imagery movements. The proposed approach was first benchmarked against two related state-of-the-art feature extraction approaches, namely, discrete cosine transform (DCT) and adaptive autoregressive (AAR)-based methods. By achieving an accuracy of 67.35%, the LP-SVD approach outperformed the other approaches by large margins (25% compared with DCT and 6 % compared with AAR-based methods). To further improve the discriminatory capability of the extracted features and reduce the computational complexity, we enlarged the extracted feature subset by incorporating two extra features, namely, Q- and the Hotelling’s T 2 statistics of the transformed EEG and introduced a new EEG channel selection method. The performance of the EEG classification based on the expanded feature set and channel selection method was compared with that of a number of the state-of-the-art classification methods previously reported with the BCI IIIa competition data set. Our method came second with an average accuracy of 81.38%.
关键词： feature extraction,linear prediction,Brain-computer interface,orthogonal transform,channel selection
更新于2025-09-23 15:21:01
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[IEEE 2019 IEEE 26th International Symposium on the Physical and Failure Analysis of Integrated Circuits (IPFA) - Hangzhou, China (2019.7.2-2019.7.5)] 2019 IEEE 26th International Symposium on Physical and Failure Analysis of Integrated Circuits (IPFA) - Optical Failure Analysis on Pulsed Signals Embedded in Logic Cloud a?? A Case Study of Laser Voltage Tracing
摘要： A key problem in wireless mesh networks is forwarding packets to/from one or more gateways with connectivity to the Internet. In this respect, a short link schedule, which determines the transmission time of links, is critical. To date, existing link schedulers do not consider routers that incorporate advances in multiple input multiple output communications, i.e., interference cancellation and spatial multiplexing. In particular, these routers are able to transmit or receive distinct packets on all their links concurrently as well as deliver multiple packets to a neighbor simultaneously. To this end, we consider the problem of deriving a time division multiple access schedule that forwards packets to their respective destination quickly. We ?rst consider the personalized broadcast problem, which assumes a single gateway and present Algo-PB, a solution that produces a schedule that is within 34.5% of the lower bound, and is 45.5% shorter than those computed by the state-of-the-art algorithms. We then extend the problem to consider multiple gateways. This so-called forest construction problem is modeled as an integer linear program (ILP). We then outline Algo-FC, a novel heuristic that generates a balanced forest by repeatedly picking a node from the heaviest tree and migrating it to another tree if doing so reduces the overall load. Experiment results show that the resulting forest generated by Algo-FC is within 9.1% of the ILP solution.
关键词： Link scheduler,multiple gateways,balanced tree,NP-complete,integer linear program (ILP)
更新于2025-09-23 15:21:01
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Explosion induced rogue waves and chaotic multi-pulsing in a passively mode-locked all-normal dispersion fiber laser
摘要： In this work, an experimental study of non-stationary pulse dynamics consisting of explosion events and chaotic multi-pulsing from an all-normal dispersion Yb-fiber laser operating in noise-like pulse (NLP) state have been reported. During explosion in NLP state, which resembled soliton explosion, dispersive Fourier transform measurements revealed large, intermittent amplitude fluctuations in the real-time spectrum indicative of rogue waves. The fluctuations either appeared randomly at the lasing wavelength within the Yb-gain spectra or at the frequency downshifted Raman Stokes wavelength. It was also observed that such fluctuation at the Raman wavelength could even exceed the amplitude of the spectral components at the main lasing wavelength. With suitable adjustments, the laser operation could be switched to chaotic multi-pulsing state where the acquisition of a large number of consecutive roundtrips revealed inter-pulse motion with unique trajectories occurring over millisecond time scales.
关键词： optical rogue waves,multi-pulsing,non-stationary pulse dynamics,noise-like pulse,fiber lasers,mode-locked fiber lasers,non-linear dynamics
更新于2025-09-23 15:21:01
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[IEEE 2019 IEEE Canadian Conference of Electrical and Computer Engineering (CCECE) - Edmonton, AB, Canada (2019.5.5-2019.5.8)] 2019 IEEE Canadian Conference of Electrical and Computer Engineering (CCECE) - Targets Illumination Region Effect on Laser RCS in Random Media for H-Wave Polarization
摘要： The classification accuracy of a brain–computer interface (BCI) frequently suffers from ill-posed and overfitting problems. To avoid and alleviate these problems, we propose a method of a multilinear discriminant analysis with constraints to augment parameter reduction, regularization, and additional prior information for event-related potential (ERP)-based BCIs. The method reduces the number of parameters by multilinearization, regularizes the ill-posedness via subspaces that constrain the parameter spaces, and incorporates a brain functional connectivity through the constraints. The experimental results show that the proposed method improved the classification accuracy rates in a single-trial ERP processing.
关键词： multilinear algebra,single-trial classification,linear discriminant analysis,Brain–computer/machine interface (BCI/BMI),event-related potentials,electroencephalogram (EEG)
更新于2025-09-23 15:21:01
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A generalised approach to calculate various transport observables for a linear array of series and parallel quantum dots
摘要： A systematic generalised approach to ?nd transport observables for a linear array of different quantum dot (QD) systems has been discussed, using non-equilibrium Green function (NEGF) formalism, in the presence of on-dot Coulomb interaction and inter-dot tunnelling. The equation of motion (EOM) method has been used to derive expressions for Green functions (GFs) within the simplest mean-?eld approximation to tackle the Coulomb correlation term. Starting from the mathematical structures of GFs for single, double and triple quantum dot systems, the expressions for GFs and transport observables have been generalised for the quantum dot systems containing N number of quantum dots in series as well as parallel linear array of dots. Further, the formulae so obtained have been used for numerical calculations of transmission probability and the I –V characteristics of linear arrays of quantum dots in series as well as parallel con?guration containing up to three dots. The results show that, with the increase in number of dots in the scattering region, transmission probability and electron current decrease in series case, while both quantities increase in parallel con?guration of dots. The inter-dot tunnelling leads to the splitting of transmission peaks in double QD system in series case whereas, it induces Fano effect in triple QD system in parallel con?guration.
关键词： quantum dots,Quantum transport,non-equilibrium Green function,Landauer–Buttiker formula,linear array of dots
更新于2025-09-23 15:21:01
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[IEEE 2019 IEEE International Conference on Computation, Communication and Engineering (ICCCE) - Fujian P.R, China (2019.11.8-2019.11.10)] 2019 IEEE International Conference on Computation, Communication and Engineering (ICCCE) - Real-Time Threshold Voltage and Mobility Compensation for Large-Size AMOLED Displays
摘要： A new real-time compensation method of threshold voltage (Vth) and mobility ((cid:2)) for large size AMOLED display named ‘linear charging sensing (LCS)’ is proposed in this paper. This compensation method can accomplish the Vth and (cid:2)(cid:3) sensing within tens or hundreds microseconds which can realize the sensing for all the pixels of FHD (1920×1080) AMOLED display within one frame time. By simulation analysis, LCS compensation method is found to have high accuracy for Vth sensing with an error of 0.07V for (cid:4)(cid:5)th(cid:6)(cid:7)(cid:8)(cid:9)(cid:5)(cid:3) (cid:10)(cid:11)(cid:12)(cid:3) (cid:11)(cid:13)(cid:3) (cid:14)(cid:15)(cid:15)(cid:13)(cid:15)(cid:3) (cid:16)(cid:13)(cid:15)(cid:3) (cid:4)(cid:5)th=-0.5V. Verified in FHD AMOLED panel further, the proposed method improves image sticking and luminance uniformity significantly.
关键词： linear charge sensing,AMOLED,compensation,TFT,threshold voltage
更新于2025-09-23 15:21:01
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Optimizing the light delivery of linear-array-based photoacoustic systems by double acoustic reflectors
摘要： Although linear transducer arrays have been intensely used in photoacoustic imaging, their geometrical shape constrains light illumination. Today, most linear array based photoacoustic systems utilize side-illumination geometry, which consists of two line fiber bundles attached to the side of the probe. The angled light illumination increases the light travel distance in deep tissue, consequently limiting the imaging depth. This issue was partially addressed by adding a right angle prism in front of the transducer. While this design makes the light illumination and acoustic detection co-axial, the transducer and the fiber bundles are orthogonal to each other, making the system inconvenient for handheld use. To overcome this limitation, here we propose a double-reflector design, in which the second reflector redirects the acoustic signals by another 90°, so that the transducer and the fiber bundle are now parallel to each other. In this design, both the transducer and fiber bundle output are fitted into a compact housing for convenient handheld imaging. To evaluate the efficiency of our design, we performed various phantom and human in vivo experiments. Our results demonstrate that the double-reflector design indeed provides deeper imaging depth and it also allows for easy imaging of objects with uneven surfaces.
关键词： handheld imaging,photoacoustic imaging,co-axial illumination,double-reflector design,linear transducer arrays
更新于2025-09-23 15:21:01
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Wind load analysis of a new linear Fresnel receiver assembly design
摘要： A linear Fresnel collector includes a low-profile reflector array and a receiver assembly with one or more absorber tubes and an optional secondary reflector. This combined optical system concentrates sunlight and converts it into thermal energy. The design of a receiver assembly is critical to the performance of a linear Fresnel collector. A position deviation of a few centimeters for the receiver assembly can result in notably reduced performance, thus leading to a direct loss in revenue associated with thermal power production. Wind load is one of the most significant environmental factors that can alter the optical—and therefore thermal—performance of a solar power system due to displacements after installation. At the same time, an over-designed receiver assembly may add unnecessary construction cost to a typically high-cost-constrained system. Thus, wind load analysis is particularly important when considering optimal engineering design of a receiver assembly and its supporting structure to cost-effectively mitigate the impacts of wind. In this study, a detailed computational fluid dynamics (CFD) model is adopted to derive the wind load of a commercial linear Fresnel receiver assembly. This wind load is then used as a reference to optimize the detailed engineering design. The CFD model is first carefully developed and benchmarked within a critical regime toward turbulence. The drag force, lift force, and vortex-shedding frequencies are derived at both the operating and survival wind-speed limits for target project deployment locations. The wind load analysis results provide a valuable reference for future engineering design and prototyping.
关键词： wind load analysis,receiver assembly,linear Fresnel collector,vortex-shedding frequencies,drag force,computational fluid dynamics,lift force
更新于2025-09-23 15:21:01