- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2018 Cross Strait Quad-Regional Radio Science and Wireless Technology Conference (CSQRWC) - Xuzhou (2018.7.21-2018.7.24)] 2018 Cross Strait Quad-Regional Radio Science and Wireless Technology Conference (CSQRWC) - Gaussian Beam Scattering from a Sphere on or Near a Plane Surface
摘要： A theoretical procedure is presented for calculating the scattered fields from a sphere on or near a plane surface. The incident Gaussian beam is expanded in series of cylindrical vector wave functions, and the scattered as well as internal fields in series of spherical ones. By using the boundary conditions and the method of moments technique, the unknown expansion coefficients are determined. Numerical results of the normalized differential scattering cross section are given, and the scattering characteristics are discussed concisely.
关键词： sphere above a plane surface,Scattering,Gaussian beam
更新于2025-09-23 15:23:52
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Effect of anisotropic non-Kolmogorov turbulence on the evolution behavior of Gaussian Schell-model vortex beams
摘要： The effect of anisotropic non-Kolmogorov turbulence on the evolution behavior of average intensity and coherent vortices for Gaussian Schell-model (GSM) vortex beams is investigated. Based on the extended Huygens–Fresnel principle and power spectrum of the anisotropic non-Kolmogorov turbulence, the analytical expressions for the cross-spectral density and average intensity of GSM vortex beams propagating through anisotropic non-Kolmogorov turbulence are obtained. The evolution behavior of intensity and coherent vortices for GSM vortex beams in anisotropic non-Kolmogorov turbulence has been discussed in detail by numerical simulation. The results shown that the evolution behavior of coherent vortices and intensity profile depends on the effective anisotropic factor, generalized exponent factor and structure constant of anisotropic non-Kolmogorov turbulence, as well as the beam parameters, such as beam waist, wave length and correlation length.
关键词： Gaussian Schell-model vortex beams,Anisotropic non-Kolmogorov turbulence,Evolution behavior of coherent vortices
更新于2025-09-23 15:23:52
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Gaussian Decomposition of LiDAR Waveform Data Simulated by Dart
摘要： Light Detection And Ranging (LiDAR) techniques have been extensively applied in spaceborne, airborne and ground-based platforms. Understanding LiDAR data requires modeling approaches that can precisely account for the physical interactions between the emitted laser pulse and reflecting targets. Diverse LiDAR data types arise from different systems, platforms, and applications. However, most existing physical models consider only single pulse configurations to simulate large footprint LiDAR waveforms, which do not correspond to standard data formats. Hence, in many cases, model outputs are not well adapted to research conducted with actual LiDAR systems, especially for Aerial and Terrestrial Laser Scanning (ALS and TLS) systems. The Discrete Anisotropic Radiation Transfer (DART) model provides accurate and efficient simulations of multiple LiDAR pulses from all platform types. This paper presents the latest development of the DART LiDAR module: Gaussian decomposition of the simulated ALS and TLS waveforms followed by the provision of LiDAR point cloud and waveforms in text and standard ASPRS LAS formats.
关键词： point cloud,DART,waveform,LiDAR,ALS,Gaussian decomposition,TLS
更新于2025-09-23 15:23:52
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[IEEE 2018 Signal Processing: Algorithms, Architectures, Arrangements, and Applications (SPA) - Poznan, Poland (2018.9.19-2018.9.21)] 2018 Signal Processing: Algorithms, Architectures, Arrangements, and Applications (SPA) - Hardware implementation of the Gaussian Mixture Model foreground object segmentation algorithm working with ultra-high resolution video stream in real-time
摘要： In this paper a hardware implementation of the Gaussian Mixture Model algorithm for background modelling and foreground object segmentation is presented. The proposed vision system is able to handle video stream with resolution up to 4K (3840x2160 pixels) and 60 frames per second. Moreover, the constraints caused by memory bandwidth limit are also discussed and a few different solutions to tackle this issue have been considered. The designed modules have been verified on the ZCU102 development board with Xilinx Zynq UltraScale+ MPSoC device. Additionally, the computing performance and power consumption have been estimated.
关键词： FPGA,4K video,background modelling,real-time processing,GPU,Gaussian Mixture Model,foreground object segmentation
更新于2025-09-23 15:23:52
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Segmentation for remote-sensing imagery using the object-based Gaussian-Markov random field model with region coefficients
摘要： The Markov random ?eld (MRF) model is a widely used method for remote-sensing image segmentation, especially the object-based MRF (OMRF) method has attracted great attention in recent years. However, the OMRF method usually fails to capture the correlation between regional features by just considering the mixed-Gaussian model. In order to solve this problem and improve the segmentation accuracy, this article proposes a new method, object-based Gaussian-Markov random ?eld model with region coe?cients (OGMRF-RC), for remote-sensing image segmentation. First, to describe the complicated interactions among regional features, the OGMRF-RC method employs the region size and edge information as region coe?cients to build the each object-based region. Second, the classic Gaussian-Markov model is extended to region level for modelling the errors in OLREs. Finally, the segmentation is achieved through a principled probabilistic inference designed for the OGMRF-RC method. Experimental results over synthetic texture images and remote-sensing images from di?erent datasets show that the proposed OGMRF-RC method can achieve more accurate segmentation than other state-of-the-art MRF-based methods and the method using convolutional neural networks.
关键词： Segmentation,Gaussian-Markov random field,region coefficients,object-based,remote-sensing imagery
更新于2025-09-23 15:23:52
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[IEEE 2018 15th Conference on Computer and Robot Vision (CRV) - Toronto, ON, Canada (2018.5.8-2018.5.10)] 2018 15th Conference on Computer and Robot Vision (CRV) - Learning a Bias Correction for Lidar-Only Motion Estimation
摘要： This paper presents a novel technique to correct for bias in a classical estimator using a learning approach. We apply a learned bias correction to a lidar-only motion estimation pipeline. Our technique trains a Gaussian process (GP) regression model using data with ground truth. The inputs to the model are high-level features derived from the geometry of the point-clouds, and the outputs are the predicted biases between poses computed by the estimator and the ground truth. The predicted biases are applied as a correction to the poses computed by the estimator. Our technique is evaluated on over 50 km of lidar data, which includes the KITTI odometry benchmark and lidar datasets collected around the University of Toronto campus. After applying the learned bias correction, we obtained significant improvements to lidar odometry in all datasets tested. We achieved around 10% reduction in errors on all datasets from an already accurate lidar odometry algorithm, at the expense of only less than 1% increase in computational cost at run-time.
关键词： Lidar Odometry,Gaussian Process,Motion Estimation,Bias Correction
更新于2025-09-23 15:23:52
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Space-variant generalised Gaussian regularisation for image restoration
摘要： We propose a new space-variant regularisation term for variational image restoration based on the assumption that the gradient magnitudes of the target image distribute locally according to a half-Generalised Gaussian distribution. This leads to a highly ?exible regulariser characterised by two per-pixel free parameters, which are automatically estimated from the observed image. The proposed regulariser is coupled with either the L2 or the L1 ?delity terms, in order to e?ectively deal with additive white Gaussian noise or impulsive noises such as, e.g. additive white Laplace and salt and pepper noise. The restored image is e?ciently computed by means of an iterative numerical algorithm based on the alternating direction method of multipliers. Numerical examples indicate that the proposed regulariser holds the potential for achieving high-quality restorations for a wide range of target images characterised by di?erent gradient distributions and for the di?erent types of noise considered.
关键词： alternating direction method of multipliers,half-Generalised Gaussian distribution,Image restoration,variational methods
更新于2025-09-23 15:23:52
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[IEEE 2018 IEEE Biomedical Circuits and Systems Conference (BioCAS) - Cleveland, OH, USA (2018.10.17-2018.10.19)] 2018 IEEE Biomedical Circuits and Systems Conference (BioCAS) - Gaussian Monocycle Pulse Generator with Calibration Circuit for Breast Cancer Detection
摘要： Gaussian Monocycle Pulses (GMP) play a very important role in a radar-based painless breast cancer detection system. In order to guarantee the detection accuracy, it is necessary to stabilize the pulse width and the amplitude under the influence of the manufacturing variation of MOSFETs. Therefore, in this paper, the GMP generator with a calibration circuit is proposed. The calibration circuit for adjusting the delay time of each path is realized by MOS capacitor array. The proposed GMP generator has a center frequency of 5.5 GHz, -3dB bandwidth from 2.8 GHz to 9.1 GHz, and 498.6 μW power consumption.
关键词： Gaussian Monocycle Pulse (GMP),equivalent time sampling,breast cancer detection system,calibration circuit
更新于2025-09-23 15:23:52
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Atom localization using Laguerre-Gaussian beams
摘要： Use of the Laguerre-Gaussian beams in an atom-light interaction makes the linewidth of the optical spectrum narrow. We exploit this fact for providing the ability to accomplish simultaneous ultra-high precision and spatial resolution atom localization in a double-Λ atomic system; under multi-photon resonance condition, the resolution of the localization is remarkably improved so that the atom can be localized in a region smaller than λ/100 × λ/100. Most prominently, the probability of finding the atom at a particular position is always 100%, when a photon with certain frequencies is absorbed or amplified. Such features are mainly attributed to radial dependence associated with the Laguerre-Gaussian beams in a spatially dependent atom-light interaction.
关键词： Laguerre-Gaussian beams,probe absorption,2D atom localization
更新于2025-09-23 15:23:52
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Controlling the relativistic self-focusing of Hermite-cosh-Gaussian beams in plasma
摘要： The purpose of current study was to find the effects of Hermite-cosh-Gaussian (HChG) beam characteristics on the relativistic self-focusing. The Self-focusing Parameter (SFP), for mode indexes of m=0, 1, and 2 is proposed which provides a basis for achieving the nonlinear self-focusing dependencies on the beam characteristics. The dissimilar nonlinear self-focusing dependencies of different mode indexes on the initial intensity and decentered parameter of HChG beam are founded. The predictions of SFP model are then validated by investigating the beam focusing/diverging along the propagation axis and the exact conformity is observed. The results of introduced model can by applied for HChG beams with higher mode indexes, the Hermite Gaussian and cosh-Gaussian beams.
关键词： Hermite-cosh-Gaussian beam,mode indices,Decentered parameter,Plasma,Relativistic self-focusing
更新于2025-09-23 15:23:52