- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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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) - The Fast Modification of Evolutionary Bioinspired Cat Swarm Optimization Method
摘要： In this paper, we propose a novel probabilistic method for the task of text-independent speaker identification (SI). In order to capture the dynamic information during SI, we design super-mel-frequency cepstral coefficients (MFCCs) features by cascading three neighboring MFCCs frames together. These super-MFCC vectors are utilized for probabilistic model training such that the speaker’s characteristics can be sufficiently captured. The probability density function (PDF) of the aforementioned super-MFCCs features is estimated by the recently proposed histogram transform (HT) method. To recede the commonly occurred discontinuity problem in multivariate histograms computing, more training data are generated by the HT method. Using these generated data, a smooth PDF of the super-MFCCs vectors is obtained. Compared with the typical PDF estimation methods, such as Gaussian mixture model, promising improvements have been obtained by employing the HT-based model in SI.
关键词： Speaker identification,Gaussian mixture model,mel-frequency cepstral coefficients,histogram transform model
更新于2025-09-23 15:21:01
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[IEEE 2019 IEEE 2nd International Conference on Knowledge Innovation and Invention (ICKII) - Seoul, Korea (South) (2019.7.12-2019.7.15)] 2019 IEEE 2nd International Conference on Knowledge Innovation and Invention (ICKII) - A Physical Threshold Voltage Model of Nanoscale Ultra-thin Body Ultra-thin Box SOI MOSFETs with a Gaussian Doping Profile
摘要： An insightful study of the virtual cathode is performed for the nanoscale ultra-thin body ultra-thin box SOI MOSFETs with a vertical Gaussian doping. And the physical, compact threshold voltage model is derived based on an analytical solution of two-dimensional Poisson equation with the evanescent-mode analysis. The accuracy of the model has been verified by 2D numerical device simulations using Sentaurus Technology Computer-Aided Design (TCAD) from Synopsys. Applying the newly developed model, the threshold voltage sensitivities to channel length, silicon-film thickness, buried-oxide thickness, and the channel doping concentration have been comprehensively investigated. Good agreements are achieved. Model predictions indicate that the individual UTBB-SOI MOSFET with a non-uniform doping profile is feasible at 10 nm scale. This work has both theoretical and practical significance and provide aids in promoting theoretical modeling research and applications of new UTBB-SOI based devices.
关键词： UTBB-SOI MOSFET,Analytical model,Gaussian doping,Virtual cathode
更新于2025-09-23 15:21:01
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Star Centroiding Based on Fast Gaussian Fitting for Star Sensors
摘要： The most accurate star centroiding method for star sensors is the Gaussian ?tting (GF) algorithm, because the intensity distribution of a star spot conforms to the Gaussian function, but the computational complexity of GF is too high for real-time applications. In this paper, we develop the fast Gaussian ?tting method (FGF), which approximates the solution of the GF in a closed-form, thus signi?cantly speeding up the GF algorithm. Based on the fast Gaussian ?tting method, a novel star centroiding algorithm is proposed, which sequentially performs the FGF twice to calculate the star centroid: the ?rst FGF step roughly calculates the Gaussian parameters of a star spot and the noise intensity of each pixel; subsequently the second FGF accurately calculates the star centroid utilizing the noise intensity provided in the ?rst step. In this way, the proposed algorithm achieves both high accuracy and high ef?ciency. Both simulated star images and star sensor images are used to verify the performance of the algorithm. Experimental results show that the accuracy of the proposed algorithm is almost the same as the GF algorithm, higher than most existing centroiding algorithms, meanwhile, the proposed algorithm is about 15 times faster than the GF algorithm, making it suitable for real-time applications.
关键词： Gaussian ?tting,real-time,star centroiding,star sensor
更新于2025-09-23 15:21:01
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Transition kinetics of impurity doped quantum dots under time-dependent confinement potential: role of noise
摘要： Present study endeavors to analyze the role of Gaussian white noise and fluctuating confinement potential on time-average excitation rate (TAER) of impurity doped quantum dot (QD). The TAER profiles are exhaustively monitored as a number of physical quantities are varied over a range with and without noise. Application of noise to the system takes place in two different pathways known as ‘additive’ and ‘multiplicative’. And the fluctuation of the confinement potential has been considered to be cosinusoidal and random which induces the excitation of ground state electronic population to the higher states. The TAER profiles comprise of features like steady increase/decrease, maximization, minimization and saturation. However, the specific characteristics of a particular profile depend on presence/absence of noise, the noise mode, the nature of fluctuating confinement potential and the identity of the physical quantity being varied. Production of large TAER of doped QD depends on noise-mode and nature of fluctuating confinement potential based on which the noise strength is required to be maintained in the vicinity of some typical values.
关键词： additive noise,Gaussian white noise,time-average excitation rate,impurity doped quantum dot,multiplicative noise,fluctuating confinement potential
更新于2025-09-23 15:21:01
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Focusing properties of spirally polarized sinh Gaussian beam
摘要： The tight focusing properties of spirally polarized sinh-Gaussian beam is investigated numerically by vector diffraction theory. Results show that the optical intensity in focal region of spirally polarized sinh Gaussian beam can be altered considerably by the beam order, relative waist width and the spiral parameter that indicates the polarization spiral degree of the spirally polarized sinh Gaussian beam. Many novel focal patterns including flattop profile, focal hole axially separated focal spots and focal spot with long focal depth are evolved considerably for the suitable beam parameters. We expect such a tunable focal patterns are useful for optical manipulation of micro particles.
关键词： Vector diffraction theory,spirally polarized sinh Gaussian beam,Focusing property
更新于2025-09-23 15:21:01
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Analyzing role of relaxation time on second harmonic generation and optical dielectric function of impurity doped quantum dots under the aegis of noise
摘要： Present study monitors the influence of relaxation time (τ) on second harmonic generation (SHG) and total optical dielectric function (TODF) of impurity containing quantum dot (QD) under the stewardship of Gaussian white noise. Two distinct roadways viz. ‘additive’ and ‘multiplicative’ have been exploited for the entrance of noise to the system. Both in absence and presence of noise the SHG and TODF peak positions do not exhibit any shift with increase in τ. The SHG peak values display monotonic behavior with the variation of τ. However, the TODF peak values delicately depend on variation of τ being guided by the presence of noise and also on its mode of introduction. Presence of additive (multiplicative) noise causes enhancement (suppression) of SHG and TODF peak values as τ varies over a range. The findings appear to be crucial in the fabrication of QD-based opto-electronic devices where role of noise deserves to be properly addressed.
关键词： Quantum dot,Gaussian white noise,Impurity,Total optical dielectric function,Relaxation time,Second harmonic generation
更新于2025-09-23 15:21:01
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Visual Servoing With Photometric Gaussian Mixtures as Dense Feature
摘要： The direct use of the entire photometric image information as dense feature for visual servoing brings several advantages. First, it does not require any feature detection, matching, or tracking process. Thanks to the redundancy of visual information, the precision at convergence is really accurate. However, the corresponding highly nonlinear cost function reduces the convergence domain. In this paper, we propose a visual servoing based on the analytical formulation of Gaussian mixtures to enlarge the convergence domain. Pixels are represented by two-dimensional Gaussian functions that denotes a “power of attraction.” In addition to the control of the camera velocities during the servoing, we also optimize the Gaussian spreads allowing the camera to precisely converge to a desired pose even from a far initial one. Simulations show that our approach outperforms the state of the art and real experiments show the effectiveness, robustness, and accuracy of our approach.
关键词： photometric Gaussian mixture,Large convergence domain,visual servoing
更新于2025-09-23 15:21:01
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Non-Local Means Image Denoising using Shapiro-Wilk Similarity Measure
摘要： Most of the real-time image acquisitions produce noisy measurements of the unknown true images. Image denoising is the post-acquisition technique to improve the signal-to-noise ratio (SNR) of the acquired images. Denoising is an essential pre-processing step for different image processing applications such as image segmentation, feature extraction, registration and other quantitative measurements. Among different denoising methods proposed in the literature, the non-local means method is a preferred choice for images corrupted with additive Gaussian noise. Conventional non-local means ?lter (CNLM) suppresses noise in a given image with minimum loss of structural information. In this paper, we propose modi?cations to CNLM algorithm where the samples are selected statistically using Shapiro-Wilk test. The experiments on standard test images demonstrate the effectiveness of the proposed method.
关键词： Shapiro-Wilk test,Noise,Denoising,Gaussian,Non-Local Means
更新于2025-09-23 15:21:01
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Quality of Transmission Aware Optical Networking using Enhanced Gaussian Noise Model
摘要： We present a new joint routing, wavelength, and power allocation method for optical network planning. The introduced gradient-based convex optimization approach has a lower computational complexity, compared to common linear programming techniques, suitable for both static as well as time-critical dynamic network planning with fast convergence requirement. The proposed scheme takes physical-layer impairments into account, using the enhanced Gaussian noise nonlinear model. In contrast to methods exploiting the theoretical full link spectrum utilization assumption (fully occupied fiber-optic C-band spectrum), we focus on maximizing the network achievable rate (AR) and minimum signal-to-noise ratio (SNR) margin of networks with partial spectrum utilization in their links, relevant to the majority of empirical metro network scenarios. According to numerical results, the network achievable rate can be improved around 17% by performing power optimization over the individual launch power of network lightpaths compared to optimizing a single flat (equal) launch power for all the lightpaths. Moreover, the minimum SNR margin of the simulated network is improved by about 2.3 dB. Finally, it is observed that maximizing the network minimum SNR margin needs the launch power of each lightpath to be proportional to the total nonlinear interference noise efficiency influencing the lightpath.
关键词： non-linear effects,routing and wavelength assignment,optical network optimization,network planning,Enhanced Gaussian noise model,power allocation,coherent transmission
更新于2025-09-23 15:21:01
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[IEEE 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Odessa, Ukraine (2018.9.4-2018.9.7)] 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Pulse Signal Propagation in Bragg-Type Layered Structures
摘要： Propagation of sinc(x), Gaussian, Lorenz, and exponential time pulses in Bragg reflectors, resonators with walls in the form of Bragg reflectors is under consideration. The influence of the number of layers in elements of the structure on the form of pulse is studied. The analysis is done in the comparison with properties of the structure in frequency domain including behavior of zeros of frequency characteristic. Influence of properties of zeros and minimal-phase characteristics on negative group delay manifestation is revealed. The application of exponential approximation of time-domain signals is investigated.
关键词： Bragg-type layered structures,exponential time pulses,zero,Gaussian,Lorenz,negative delay
更新于2025-09-23 15:21:01