- 标题
- 摘要
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- 实验方案
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[IEEE 2019 IEEE Innovative Smart Grid Technologies - Asia (ISGT Asia) - Chengdu, China (2019.5.21-2019.5.24)] 2019 IEEE Innovative Smart Grid Technologies - Asia (ISGT Asia) - Emergency Control for Improving Transient Stability of Integrated Systems with Photovoltaic and Hydropower Stations Based on EEAC Theory
摘要： Integrated systems with photovoltaic (PV) and hydropower stations can make full use of energy. However, the system may be prone to transient instability due to the weak grid and low inertia characteristic of PV stations. This paper presents an emergency control method for transient stability enhancement of the integrated system with PV and hydropower stations based on the extended equal area criterion (EEAC) theory. Firstly, when the system is disturbed, it can be equivalent to a single machine infinite system. Subsequently, the equivalent electromagnetic power curve is fitted considering the influence of PV stations based on the least square method. Moreover, the equal area criterion is used to determine the control quantity of generator tripping. Finally, simulation results provided by BPA are performed to validate the effectiveness of the proposed method.
关键词： generator tripping,extended equal area criterion (EEAC),photovoltaic,hydro power,Transient stability
更新于2025-09-11 14:15:04
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MULTISPECTRAL IMAGING SYSTEM FOR QUANTITATIVE ASSESSMENT OF TRANSCUTANEOUS BLOOD OXYGEN SATURATION
摘要： This paper presents the use of Extended Modified Lambert Beer (EMLB) model for quantification of transcutaneous blood oxygen saturation (StO2) via a noninvasive approach. Continuous wave (CW) reflectance spectroscopy system is employed for measurement of intensity reflected from left index finger of an Asian nonsmoking volunteer at resting condition. Multispectral images captured in the wavelength range of 520 ? 600 nm at an interval of 10 nm are mathematically analyzed and fitted using the developed fitting algorithm to give the best estimation of StO2. The result from this preliminary study revealed a mean StO2 value of 75 ± 5% for the participating individual, which value agreed considerably well with that presented in previous works. This work concluded that the developed spectroscopy system and quantification technique can potentially be used as an alternative means to clinical assessment of wound healing progress.
关键词： Transcutaneous blood oxygen saturation,reflectance spectroscopy,Extended Modified Lambert Beer model,skin oximetry
更新于2025-09-11 14:15:04
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Nonlinear Hyperspectral Unmixing Via Modelling Band Dependent Nonlinearity
摘要： Wavelength dependent nonlinearity is an essential issue in hyperspectral unmixing, which was overlooked in the past. In this paper, a band-wise nonlinear unmixing method is presented. An extended multilinear mixing model is adopted for interpreting different degrees of nonlinear contributions per band. Moreover, regularizers including abundances’ sparsity and nonlinear parameters’ smoothness are exploited to formulate the optimization problem and obtain better unmixing results. Finally, unmixing is implemented in the scheme of alternating direction method of multipliers. Experimental results on both simulated and real hyperspectral data validate that the proposed method can improve the unmixing accuracy and reveal the change of nonlinearity at each band as well.
关键词： extended multilinear mixing model,nonlinear spectral unmixing,constrained optimization,Hyperspectral imagery,wavelength-wise nonlinearity
更新于2025-09-10 09:29:36
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Evaluating Scattered Electromagnetic Field from Fractal Surface Using its Components
摘要： In this paper, a novel method is proposed to evaluate the scattered field from rough surfaces by decomposition-reconstitution. The extended boundary condition method (EBCM) is employed in conjunction with a Weierstrass Mandelbrot (WM) function for fractal surface profile and its components. WM function can be decomposed into a series of sinusoidal profile. The properties of the sinusoidal profile and WM function to be periodic and almost periodic allow the deriving respective amplitudes of the scattered Floquet modes. The superposition of scattered fields from each sinusoidal component is consistent with the scattered field from WM surface. The result has compared with AIEM in backscattering coefficients. Thus, by calculating the scattered information for each sinusoidal component of the rough surface, we can obtain the overall scattered field.
关键词： Fractal,Scattered field superposition,Rough surface decomposition,Extended Boundary Condition Method,Electromagnetic Scattering
更新于2025-09-10 09:29:36
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Extreme Sparse Multinomial Logistic Regression: A Fast and Robust Framework for Hyperspectral Image Classification
摘要： Although sparse multinomial logistic regression (SMLR) has provided a useful tool for sparse classification, it suffers from inefficacy in dealing with high dimensional features and manually set initial regressor values. This has significantly constrained its applications for hyperspectral image (HSI) classification. In order to tackle these two drawbacks, an extreme sparse multinomial logistic regression (ESMLR) is proposed for effective classification of HSI. First, the HSI dataset is projected to a new feature space with randomly generated weight and bias. Second, an optimization model is established by the Lagrange multiplier method and the dual principle to automatically determine a good initial regressor for SMLR via minimizing the training error and the regressor value. Furthermore, the extended multi-attribute profiles (EMAPs) are utilized for extracting both the spectral and spatial features. A combinational linear multiple features learning (MFL) method is proposed to further enhance the features extracted by ESMLR and EMAPs. Finally, the logistic regression via the variable splitting and the augmented Lagrangian (LORSAL) is adopted in the proposed framework for reducing the computational time. Experiments are conducted on two well-known HSI datasets, namely the Indian Pines dataset and the Pavia University dataset, which have shown the fast and robust performance of the proposed ESMLR framework.
关键词： extreme sparse multinomial logistic regression (ESMLR),extended multi-attribute profiles (EMAPs),hyperspectral image (HSI) classification,linear multiple features learning (MFL),sparse multinomial logistic regression (SMLR),Lagrange multiplier
更新于2025-09-10 09:29:36
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Solitons in optical metamaterials with anti-cubic law of nonlinearity by ETEM and IGEM
摘要： This paper studies soliton perturbation in optical metamaterials, with anticubic nonlinearity. Methods: Two integration approaches, namely, the extended trial equation method (ETEM) and the improved G’/G-expansion method (IGEM) are presented. Results: Bright, dark and singular soliton solutions are retrieved. The existence criteria of these solitons in metamaterials are also demonstrated. All solutions have been verified back into its corresponding equation with the aid of maple package program. Conclusions: Finally, we believe that the executed method is robust and efficient than other methods and the obtained solutions in this paper can help us to understand the variation of solitary waves in optical metamaterials.
关键词： Solitons,Extended trial equation method,Anti-cubic nonlinearity,Improved G’/G-expansion method,Optical metamaterials
更新于2025-09-10 09:29:36
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Piezoelectric Disc Transformer Modeling Utilizing Extended Hamilton's Principle
摘要： Piezoelectric transformers (PTs) are resonant electromechanical voltage conversion devices used in a variety of applications including voltage boosting and galvanic isolation. They offer advantages over electromagnetic voltage transformers (EMTs), including high energy density as well as the potential for monolithic fabrication, making them well suited to small-scale microelectromechanical (MEMS) applications. Among various PT topologies, circular discs lend themselves to microfabrication, and are considered here. In order to gain fundamental understanding of disc PT dynamics, this work applies the Extended Hamilton’s Principle of variational calculus to the piezoelectric electric enthalpy, using cylindrical coordinates, in order to derive electromechanical constitutive equations for bulk disc transformers. The use of the Hamilton approach in this work supports the integration of mechanical tethers that physically support the disc, allowing the model to be applied to device designs that are compatible with monolithic microfabrication from sheets of bulk piezoelectric material. Using the integrated model, voltage gain (output voltage / input voltage) is predicted as a function of multiple variables including electrode area ratio, device size, load impedance, and is compared against finite element numerical and experimental prototype results for verification. Prototype 4mm diameter tethered disc PTs on the order of .002cm3, two orders smaller than the bulk PT literature, were fabricated to validate the proposed model, and had peak voltage gains over 2.
关键词： Extended Hamilton’s Principle,Piezoelectric transformers,voltage conversion,MEMS,microfabrication
更新于2025-09-10 09:29:36
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Triangle-like inequalities related to coherence and entanglement negativity
摘要： Quantum coherence and entanglement are two key features in quantum mechanics and play important roles in quantum information processing and quantum computation. We provide a general triangle-like inequality satisfied by the l1-norm measure of coherence for convex combination of arbitrary n pure states of a quantum state ρ. Furthermore, we present triangle-like inequality for the convex-roof extended negativity for any states of rank 2, which gives a positive answer to a conjecture raised in Dai et al. (Phys. Rev. A 96:062308, 2017). Detailed examples are given to illustrate the relations characterized by the triangle-like inequalities.
关键词： Convex-roof extended negativity,Triangle-like inequality,Quantum coherence
更新于2025-09-10 09:29:36
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - An Efficient Image Formation Algorithm for Spaceborne Video SAR
摘要： To avoid unnecessary duplication of processing and meet the real-time requirement of video SAR. An image formation algorithm of spaceborne video SAR based on sub-aperture extended chirp scaling processing was proposed in this paper. Firstly the SAR raw data segmentation approach was presented to realize the SAR video frames continuous output. Then the raw data of a video frame was divided to several sub-apertures, after the extended CS processing in the sub-apertures, the frequency sub-bands of sub-apertures were combined to achieve the desired high azimuth resolution video SAR frames. This innovative image formation algorithm can avoid the duplication of processing, so as to improve computation efficiency. Finally, experiments on simulated data show that the proposed algorithm is effective.
关键词： spaceborne video SAR,extended chirp scaling algorithm,data overlap,sub-aperture processing
更新于2025-09-10 09:29:36
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Energy scaling and extended tunability of a ring cavity terahertz parametric oscillator based on KTiOPO <sub/>4</sub> crystal
摘要： A wide terahertz tuning range from 0.96 THz to 7.01 THz has been demonstrated based on ring-cavity THz wave parametric oscillator with a KTiOPO4 (KTP) crystal. The tuning range was observed intermittently from 0.96 THz to 1.87 THz, from 3.04 THz to 3.33 THz, from 4.17 THz to 4.48 THz, from 4.78 THz to 4.97 THz, from 5.125 THz to 5.168 THz, from 5.44 THz to 5.97 THz, and from 6.74 THz to 7.01 THz. The dual-Stokes wavelengths resonance phenomena were observed in some certain tuning angle ranges. Through the theoretical analysis of the dispersion curve of the KTP crystal, the intermittent THz wave tuning range and dual-wavelength Stokes waves operation during angle tuning process were explained. The theoretical analysis was in good agreement with the experiment results. The maximum THz output voltage detected by Golay cell was 1.7 V at 5.7 THz under the pump energy of 210 mJ, corresponding to the THz wave output energy of 5.47 μJ and conversion ef?ciency of 2.6 × 10?5.
关键词： terahertz parametric oscillator,extended tunability,energy scaling,KTiOPO4 crystal
更新于2025-09-10 09:29:36