- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 IEEE Sustainable Power and Energy Conference (iSPEC) - Beijing, China (2019.11.21-2019.11.23)] 2019 IEEE Sustainable Power and Energy Conference (iSPEC) - Detection of High-Impedance Line-Line Fault in Photovoltaic Arrays Based on Voltage Divider
摘要： The recently proposed dual mode logic (DML) gates family enables a very high level of energy-delay optimization flexibility at the gate level. In this paper, this flexibility is utilized to improve energy efficiency and performance of combinatorial circuits by manipulating their critical and noncritical paths. An approach that locates the design’s critical paths and operates these paths in the boosted performance mode is proposed. The noncritical paths are operated in the low energy DML mode, which does not affect the performance of the design, but allows significant energy consumption reduction. The proposed approach is analyzed on a 128 bit carry skip adder. Simulations, carried out in a standard 40 nm digital CMOS process with VDD = 400 mV, show that the proposed approach allows performance improvement of X2 along with reduction of energy consumption of X2.5, as compared with a standard CMOS implementation. At VDD = 1.1 V, improvements of 1.3X and 1.5X in performance and energy are achieved, respectively.
关键词： energy efficiency,Dual Mode Logic,critical paths,energy-delay optimization,high performance
更新于2025-09-23 15:19:57
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Two Patterns of Interocular Delay Revealed by Spontaneous Motion-in-Depth Pulfrich Phenomenon in Amblyopes with Stereopsis
摘要： PURPOSE. To assess interocular delays in amblyopes with stereopsis and to evaluate the relationship between interocular delays and the clinical characteristics. METHODS. Twenty amblyopes with stereopsis (median, 400 arcseconds) and 20 controls with normal or corrected to normal visual acuity (≤0 logMAR) and normal stereopsis (≤60 arcseconds) participated. Using a rotating cylinder defined by horizontally moving Gabor patches, we produced a spontaneous Pulfrich phenomenon in order to determine the interocular delays, that is, the interocular phase difference at which ambiguous motion in plane was perceived. Two spatial frequencies—a low (0.95 cycles/degree [c/d]) and a medium (2.85 c/d) spatial frequency—were tested. RESULTS. The absolute interocular delays of the amblyopic group was significantly longer than that of the controls at both low or medium spatial frequencies (P < 0.01). However, the interocular delays was not always in favor of the fellow eye: 35% of the amblyopes (7/20) showed a faster processing of the amblyopic eye than that of the fellow eye at 0.95 c/d and 29.5% (5/17) at 2.85 c/d. No significant correlation was found between interocular delays and the clinical characteristics (e.g., age, treatment history, stereoacuity, and magnitude of anisometropia) in this amblyopic cohort. CONCLUSIONS. The interocular delays in amblyopes with stereopsis might result from either a faster or slower processing of the amblyopic eye relative to the fellow eye. This work provides important additional information for binocular processing of dynamic visual stimuli in amblyopia. However, the special role between this form of interocular delays and patients’ clinical characteristics remains unknown.
关键词： Pulfrich phenomenon,amblyopia,interocular delay
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Modelling, Simulation, and Performance Analysis of a Microgrid with Photovoltaic Energy for Eastern Region of Saudi Arabia
摘要： We announce a new video quality model (VQM) that accounts for the perceptual impact of variable frame delays (VFD) in videos with demonstrated top performance on the laboratory for image and video engineering (LIVE) mobile video quality assessment (VQA) database. This model, called VQM_VFD, uses perceptual features extracted from spatial-temporal blocks spanning fixed angular extents and a long edge detection filter. VQM_VFD predicts video quality by measuring multiple frame delays using perception based parameters to track subjective quality over time. In the performance analysis of VQM_VFD, we evaluated its efficacy at predicting human opinions of visual quality. A detailed correlation analysis and statistical hypothesis testing show that VQM_VFD accurately predicts human subjective judgments and substantially outperforms top-performing image quality assessment and VQA models previously tested on the LIVE mobile VQA database. VQM_VFD achieved the best performance on the mobile and tablet studies of the LIVE mobile VQA database for simulated compression, wireless packet-loss, and rate adaptation, but not for temporal dynamics. These results validate the new model and warrant a hard release of the VQM_VFD algorithm. It is freely available for any purpose, commercial, or noncommercial at http://www.its.bldrdoc.gov/vqm/.
关键词： Edge detection,VQM_VFD,video quality model,video quality database,variable frame delay,video quality assessment
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE Conference on Power Electronics and Renewable Energy (CPERE) - Aswan City, Egypt (2019.10.23-2019.10.25)] 2019 IEEE Conference on Power Electronics and Renewable Energy (CPERE) - Experimental Demonstration of superior SiC MOSFET and GaN HEMT Performance within Single Phase Microinverter for Low-Power Photovoltaic Applications
摘要： In this paper, we propose joint angle-delay subspace based-channel estimation in single cell for broadband massive multiple-input and multiple-output systems employing orthogonal frequency division multiplexing modulation. Based on a parametric channel model, we present a new concept of the joint angle-delay subspace, which can be tracked by the low-complexity low-rank adaptive ?ltering algorithm. Then, we investigate an interference-free transmission condition that the joint angle-delay subspaces of the users reusing the same pilots are non-overlapping. Since the channel statistics are usually unknown, we develop a robust minimum mean square error (MMSE) estimator under the worst precondition of pilot decontamination, considering that the joint angle-delay subspaces of the interfering users fully overlap. Furthermore, motivated by the interference-free transmission criteria, we present a novel low-complexity greedy pilot scheduling algorithm to avoid the problem of initial value sensitivity. Simulation results show that the joint angle-delay subspace can be estimated effectively, and the proposed pilot reuse scheme combined with robust MMSE channel estimation offers signi?cant performance gains.
关键词： pilot scheduling,robust channel estimation.,Joint angle-delay subspace,pilot decontamination,massive MIMO-OFDM
更新于2025-09-23 15:19:57
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Self-Aligning and Flexible Dielectric Waveguide Plug for MMICs at G-Band
摘要： In this paper, we propose joint angle-delay subspace based-channel estimation in single cell for broadband massive multiple-input and multiple-output systems employing orthogonal frequency division multiplexing modulation. Based on a parametric channel model, we present a new concept of the joint angle-delay subspace, which can be tracked by the low-complexity low-rank adaptive ?ltering algorithm. Then, we investigate an interference-free transmission condition that the joint angle-delay subspaces of the users reusing the same pilots are non-overlapping. Since the channel statistics are usually unknown, we develop a robust minimum mean square error (MMSE) estimator under the worst precondition of pilot decontamination, considering that the joint angle-delay subspaces of the interfering users fully overlap. Furthermore, motivated by the interference-free transmission criteria, we present a novel low-complexity greedy pilot scheduling algorithm to avoid the problem of initial value sensitivity. Simulation results show that the joint angle-delay subspace can be estimated effectively, and the proposed pilot reuse scheme combined with robust MMSE channel estimation offers signi?cant performance gains.
关键词： pilot scheduling,robust channel estimation.,Joint angle-delay subspace,pilot decontamination,massive MIMO-OFDM
更新于2025-09-23 15:19:57
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[Institution of Engineering and Technology 8th Renewable Power Generation Conference (RPG 2019) - Shanghai, China (24-25 Oct. 2019)] 8th Renewable Power Generation Conference (RPG 2019) - Design of general framework for multifault diagnosis based on photovoltaic grid-connected inverter system
摘要： Visible light communication (VLC) systems have typically operated at data rates below 10 Gb/s and operation at this data rate was shown to be feasible by using laser diodes (LDs), imaging receivers and delay adaptation techniques (DAT imaging LDs-VLC). However, higher data rates, beyond 10 Gb/s, are challenging due to the low signal to noise ratio (SNR) and inter symbol interference (ISI). In this paper, for the first time, to the best of our knowledge, we propose, design, and evaluate a VLC system that employs beam steering (of part of the VLC beam) using adaptive finite vocabulary of holograms in conjunction with an imaging receiver and a DAT to enhance SNR and to mitigate the impact of ISI at high data rates (20 Gb/s). An algorithm was used to estimate the receiver location, so that part of the white light can be directed towards a desired target (receiver) using beam steering to improve SNR. Simulation results of our location estimation algorithm (LEA) indicated that the required time to estimate the position of the VLC receiver is typically within 224 ms in our system and environment. A finite vocabulary of stored holograms is introduced to reduce the computation time required by LEA to identify the best location to steer the beam to the receiver location. The beam steering approach improved the SNR of the fully adaptive VLC system by 15 dB at high data rates (20 Gb/s) over the DAT imaging LDs-VLC system in the worst-case scenario. In addition, we examined our new proposed system in a very harsh environment with mobility. The results showed that our proposed VLC system has strong robustness against shadowing, signal blockage, and mobility.
关键词： delay adaptation,SNR,location estimation,imaging receiver,Beam steering,finite vocabulary of holograms,ISI,laser diodes
更新于2025-09-23 15:19:57
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Double-pulse speckle contrast correlations with near Fourier transform limited free-electron laser light using hard X-ray split-and-delay
摘要： the ability to deliver two coherent X-ray pulses with precise time-delays ranging from a few femtoseconds to nanoseconds enables critical capabilities of probing ultra-fast phenomena in condensed matter systems at X-ray free electron laser (feL) sources. Recent progress made in the hard X-ray split-and-delay optics developments now brings a very promising prospect for resolving atomic-scale motions that were not accessible by previous time-resolved techniques. Here, we report on characterizing the spatial and temporal coherence properties of the hard X-ray feL beam after propagating through split-and-delay optics. Speckle contrast analysis of small-angle scattering measurements from nanoparticles reveals well-preserved transverse coherence of the beam. Measuring intensity fluctuations from successive X-ray pulses also reveals that only single or double temporal modes remain in the transmitted beam, corresponding to nearly fourier transform limited pulses.
关键词： spatial coherence,split-and-delay optics,speckle contrast,temporal coherence,X-ray Free Electron Lasers
更新于2025-09-23 15:19:57
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Method for Digital Correction of Signals of Multirow Photodetectors for Detecting Small Objects
摘要： The method of digital correction of output signals of multirow infrared (IR) photodetectors (PDs) for detecting small objects is proposed. The method makes it possible to correct the shape of impulse response distorted by high-frequency filtering inside the PD and increase the signal/noise ratio. The presented method is compared with the matched filtering method. The effectiveness of the proposed method for reducing the number of defective “abnormally noisy” PD channels is shown. The source data for calculations are the images obtained as a result of PD tests in a small object detection mode.
关键词： recursive filter,digital filter,small object,infrared,matched filter,time delay and integration,PD
更新于2025-09-23 15:19:57
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New Silica Laser-Optimized Multimode Optical Fibers with Extremely Enlarged 100-??m Core Diameter for Gigabit Onboard and Industrial Networks
摘要： We present new type of silica graded index laser-optimized multimode optical fibers (LOMF) with extremely enlarged core diameter up to 100 μm and “typical” “telecommunication” cladding diameter 125 μm. This optical fiber was designed for harsh environment Gigabit onboard cable systems and industrial networks. It differs by special optimized graded refractive index profile, providing low differential mode delay (DMD) for selected guided modes. We present some results of tests, performed for manufactured pilot 520 m length of described LOMF 100/125, concerned with its geometry properties as well as key transmission parameters—attenuation and DMD map.
关键词： mode coupling,laser-based gigabit data transmission,higher-order modes,large core multimode optical fiber,differential mode delay,short-range optical networks,industrial networks,selected guided modes,on-board cable systems,few-mode regime
更新于2025-09-23 15:19:57
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Harper-Hofstadter Topological Laser with Frequency-Dependent Gain
摘要： This letter is concerned with experimental results of aircraft positioning by using terrestrial digital broadcasting signal delay. Passive bistatic radar (PBR) is expected to be a conventional primary surveillance radar alternative, and it can also achieve expanding coverage area of the conventional radar. The PBR sensors allow the detection and tracking of noncooperative targets illuminated by transmitters of opportunity such as communication systems [digital terrestrial television broadcasting (DTTB), AM/FM, 3G/LTE base stations, etc.] or conventional radar system. Especially, the DTTB signals are the most expected radio waves. In this letter, we show experimental results of aircraft positioning by using the signal delay profile of DTTB whose type is Integrated Services Digital Broadcasting–Terrestrial (ISDB-T) used in Japan. It will be shown that the ISDB-T signal delays are useful surveillance systems.
关键词： digital terrestrial television broadcasting,multistatic primary surveillance radar (MSPSR),Aircraft surveillance,signal delay,passive bistatic radar,Integrated Services Digital Broadcasting–Terrestrial
更新于2025-09-23 15:19:57