- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 IEEE 19th International Conference on Nanotechnology (IEEE-NANO) - Macao (2019.7.22-2019.7.26)] 2019 IEEE 19th International Conference on Nanotechnology (IEEE-NANO) - Direct Transfer Printing of Dielectric Nanoparticle Assembled Superlens Array for Super-resolution Imaging <sup>*</sup>
摘要： We describe a novel iterative methodology for computing a set of low-sidelobe beamforming weights for an airborne, electronically-steered phased-array radar using an in-flight stochastic optimization routine performed over a number of coherent processing intervals (CPIs). The proposed approach is notable in that it does not rely upon a good antenna calibration and only requires digitization of the radar’s sum beam. By observing the radar ground clutter, the algorithm iteratively adjusts the beamformer. Furthermore, it is computationally inexpensive and scales favorably to radars comprising very large numbers of antenna elements and requiring extremely low sidelobes.
关键词： radar,clutter,iterative,Calibration,stochastic optimization,phased arrays
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) - Impact of Thin CuGa Layers Added at the Rear Interface of Cu <sub/>2</sub> ZnSnSe <sub/>4</sub> Solar Cells
摘要： Current neural networks are accumulating accolades for their performance on a variety of real-world computational tasks including recognition, classification, regression, and prediction, yet there are few scalable architectures that have emerged to address the challenges posed by their computation. This paper introduces Minitaur, an event-driven neural network accelerator, which is designed for low power and high performance. As an field-programmable gate array-based system, it can be integrated into existing robotics or it can offload computationally expensive neural network tasks from the CPU. The version presented here implements a spiking deep network which achieves 19 million postsynaptic currents per second on 1.5 W of power and supports up to 65 K neurons per board. The system records 92% accuracy on the MNIST handwritten digit classification and 71% accuracy on the 20 newsgroups classification data set. Due to its event-driven nature, it allows for trading off between accuracy and latency.
关键词： Deep belief networks,spiking neural networks,field programmable arrays,restricted Boltzmann machines,neural networks,machine learning
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) - Sub-stochiometric MoO <sub/>3</sub> for intermediate band solar cells
摘要： This paper proposes a novel scalable digit-serial inverter structure with low space complexity to perform inversion operation in GF(2m) based on a previously modi?ed extended Euclidean algorithm. This structure is suitable for ?xed size processor that only reuse the core and does not require to modulate the core size when m modi?ed. This structure is extracted by applying a nonlinear methodology that gives the designer more ?exibility to control the processing element workload and also reduces the overhead of communication between processing elements. Implementation results of the proposed scalable design and previously reported ef?cient designs show that the proposed scalable structure achieves a signi?cant reduction in the area ranging from 83.0% to 88.3% and also achieves a signi?cant saving in energy ranging from 75.0% to 85.0% over them, but it has lower throughput compared to them. This makes the proposed design more suitable for constrained implementations of cryptographic primitives in ultra-low power devices such as wireless sensor nodes and radio frequency identi?cation (RFID) devices.
关键词： Scalable systolic arrays,?nite ?eld inversion,ultra-low power devices,hardware security,ASIC
更新于2025-09-23 15:19:57
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Narrow plasmonic surface lattice resonances with preference to asymmetric dielectric environment
摘要： Plasmonic surface lattice resonances (SLRs) supported by metal nanoparticle arrays exhibit narrow linewidths and enhanced localized ?elds and thus are attractive in diverse applications including nanolasers, biochemical sensors and nonlinear optics. However, it has been shown that these SLRs have much worse performance in a less symmetric environment, hindering their practical applications. Here, we propose a novel type of narrow SLRs that is supported by metal-insulator-metal nanopillar arrays and that has better performance in a less symmetric dielectric environment. When the dielectric environment is as asymmetric as the air/polymer environment with a refractive index contrast of 1.0/1.52, the proposed SLRs have high quality factors of 62 under normal incidence and of 147 under oblique incidence in the visible regime. We attribute these new SLRs to Fano resonance between an in-plane dipole and an out-of-plane quadrupole (or dipole) that are respectively supported by the two metal ridges under normal (or oblique) incidence. We also show that the resonance wavelength can be tuned by varying the geometric sizes or by changing the angle of incidence. By doing this, we clarify the conditions for the formation of the proposed SLRs and illustrate their attractive merits in sensing applications. We expect that this new SLR can open up applications in asymmetric dielectric environments.
关键词： sensing applications,asymmetric dielectric environment,Plasmonic surface lattice resonances,metal-insulator-metal nanopillar arrays,Fano resonance
更新于2025-09-23 15:19:57
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[IEEE 2019 26th International Workshop on Active-Matrix Flatpanel Displays and Devices (AM-FPD) - Kyoto, Japan (2019.7.2-2019.7.5)] 2019 26th International Workshop on Active-Matrix Flatpanel Displays and Devices (AM-FPD) - Identification of Edge Recombination from CIGS Solar Cells
摘要： We study the detection and estimation of the parameters related to the deterministic model of the re?ections of room impulse responses measured with a spherical microphone array. More speci?cally, we investigate the problem of detecting and estimating several re?ections of a single snapshot of data in the spherical harmonic (SH) domain with four detection and four estimation methods, presented previously in the array processing research. Three of the estimation methods are based on Bayesian Maximum a Posteriori (MAP) estimation, and they employ a prior normal distribution on the signals. The estimation methods are compared with the deterministic maximum likelihood (DML) method [Tervo & Politis 2015]. In the detection task, two information criteria-based methods, minimum description length (MDL) and Akaike information criteria (AIC), a normalized likelihood (NL) based method, and a Bayesian detection scheme (BDS) are explored. The experiments study the performance of the methods with simulated and real data experiments. The simulation results show that the MAP estimation methods have a lower root mean squared error (RMSE) than DML in the re?ection signal amplitude estimation, but all three have similar performance in the direction of arrival (DOA) and noise variance estimation, although in general RMSE of DOA estimation of MAP methods is slightly lower that that of DML. In addition, in the detection task, the BDS and AIC are the most robust against additive noise, and NL and AIC have the best detection rate when more than two re?ections are simulated. The results of the real data experiments show that all the estimation methods have similar performance for DOA and noise variance estimation, while the Bayesian MAP methods have a clearly lower RMSE for re?ection signal amplitude estimation than DML. In total, NL has the highest detection rate in the real data experiments.
关键词： spatial room impulse response,direction of arrival,room acoustics,Detection of Re?ections,single snapshot,spherical microphone arrays
更新于2025-09-23 15:19:57
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Standalone Photovoltaic Direct Pumping in Urban Water Pressurized Networks with Energy Storage in Tanks or Batteries
摘要： Photovoltaic energy production is nowadays one of the hottest topics in the water industry as this green energy source is becoming more and more workable in countries like Spain, with high values of irradiance. In water pressurized systems supplying urban areas, they distribute energy consumption in pumps throughout the day, and it is not possible to supply electromechanical devices without energy storages such as batteries. Additionally, it is not possible to manage energy demand for water consumption. Researchers and practitioners have proven batteries to be reliable energy storage systems, and are undertaking many efforts to increase their performance, capacity, and useful life. Water pressurized networks incorporate tanks as devices used for accumulating water during low consumption hours while releasing it in peak hours. The compensation tanks work here as a mass and energy source in water pressurized networks supplied with photovoltaic arrays (not electricity grids). This work intends to compare which of these two energy storage systems are better and how to choose between them considering that these two systems involve running the network as a standalone pumping system without being connected to electricity grids. This work also calculates the intermediate results, considering both photovoltaic arrays and electricity grids for supplying electricity to pumping systems. We then analyzed these three cases in a synthetic network (used in earlier research) considering the effect of irradiation and water consumption, as we did not state which should be the most unfavorable month given that higher irradiance coincides with higher water consumption (i.e., during summer). Results show that there is no universal solution as energy consumption depends on the network features and that energy production depends very much on latitude. We based the portfolio of alternatives on investments for purchasing different equipment at present (batteries, pipelines, etc.) based on economic criteria so that the payback period is the indicator used for finding the best alternative, which is the one with the lowest value.
关键词： batteries,energy audit,tanks,photovoltaic arrays
更新于2025-09-23 15:19:57
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Empty Substrate Integrated Waveguide Fed Patch Antenna Array for 5G mm-Wave Communication Systems
摘要： This paper proposes a novel scalable digit-serial inverter structure with low space complexity to perform inversion operation in GF(2m) based on a previously modi?ed extended Euclidean algorithm. This structure is suitable for ?xed size processor that only reuse the core and does not require to modulate the core size when m modi?ed. This structure is extracted by applying a nonlinear methodology that gives the designer more ?exibility to control the processing element workload and also reduces the overhead of communication between processing elements. Implementation results of the proposed scalable design and previously reported ef?cient designs show that the proposed scalable structure achieves a signi?cant reduction in the area ranging from 83.0% to 88.3% and also achieves a signi?cant saving in energy ranging from 75.0% to 85.0% over them, but it has lower throughput compared to them. This makes the proposed design more suitable for constrained implementations of cryptographic primitives in ultra-low power devices such as wireless sensor nodes and radio frequency identi?cation (RFID) devices.
关键词： ?nite ?eld inversion,Scalable systolic arrays,ASIC,ultra-low power devices,hardware security
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE International Symposium on Phased Array System & Technology (PAST) - Waltham, MA, USA (2019.10.15-2019.10.18)] 2019 IEEE International Symposium on Phased Array System & Technology (PAST) - An Additively Manufactured, All-metallic Frequency-scaled Ultra-wide Spectrum Element (AM-FUSE) Active Electronically Scanned Array (AESA) for Space-borne Applications
摘要： A new breed of the Frequency-scaled, Ultra-wide Spectrum Element (FUSE) is built entirely from a single piece of metal using direct metal laser sintering (DMLS) for space-borne missions. An active electronically scanned array (AESA) was built that includes an 8x4 linearly polarized aperture and low-profile feed circuitry that has eight true-time delay units (TDU) to fit inside a 3U CubeSat. This AESA operates over 1.5 GHz – 6 GHz, scanning +/- 45 degrees in azimuth with a very low active voltage standing wave ratio (active VSWR). The weight of the array with its combiner and beamforming boards is less than 3 lbs.
关键词： wideband,tapered-slot,CubeSat,additive manufacturing,AESA,connector-less,phased arrays,Vivaldi,FUSE,Antennas,space missions
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE Pulsed Power & Plasma Science (PPPS) - Orlando, FL, USA (2019.6.23-2019.6.29)] 2019 IEEE Pulsed Power & Plasma Science (PPPS) - Pulsed RF Signal Irradiation Using a Low Voltage NLTL Coupled to a DRG Antenna
摘要： Field-programmable gate arrays (FPGAs) have been shown to provide high computational density and efficiency for many computing applications by allowing circuits to be customized to any application of interest. FPGAs also support programmability by allowing the circuit to be changed at a later time through reconfiguration. There is great interest in exploiting these benefits in space and other radiation environments. FPGAs, however, are very sensitive to radiation and great care must be taken to properly address the effects of radiation in FPGA-based systems. This paper will highlight the effects of radiation on FPGA-based systems and summarize the challenges in deploying FPGAs in such environments. Several well-known mitigation methods will be described and the unique ability of FPGAs to customize the system for improved reliability will be discussed. Finally, two case studies summarizing successful deployment of FPGAs in radiation environments will be presented.
关键词： radiation effects,radiation hardening,Fault-tolerant systems,integrated circuit reliability,field programmable gate arrays
更新于2025-09-23 15:19:57
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Laser Beam Shaping Applications || Laser Beam Shaping in Array-Type Laser Printing Systems
摘要： In a variety of applications, including longitudinal solid-state laser pumping,1–4 fiber coupling for fiber lasers, and line printers,5–12 laser diode arrays have proven to be very effective light sources when combined with the appropriate beam shaping optics. As laser arrays can be designed in numerous ways, such as with phase-coupled single-mode emitters, uncoupled single-mode emitters, or uncoupled multimode emitters, the output properties of both the individual beams and the ensemble of beams vary dramatically. Inherently, many beam properties, including the output power level, beam profiles and beam propagation properties, beam coherence effects, and the overall device layout, are dependent upon the emitter structure. The optical systems that have been designed to work with these highly nontraditional light sources, which are anamorphic in both physical layout and beam properties, are themselves nontraditional, and typically employ a variety of modern micro-optical components. Within that context, a variety of unique systems13–15 have been developed for high-power, high-throughput printing applications, where the laser light is transformed into a linear arrangement of individually modulated beams and imaged onto a light-sensitive media. These systems typically combine the design and analysis techniques from classical imaging optics, illumination optics, and Gaussian beam optics into integral wholes. Certainly, many of the design concepts that have evolved to support the laser thermal printing application are applicable to other endeavors, of which laser projection is an example.
关键词： beam shaping,laser thermal printing,Gaussian beam optics,micro-optical components,laser diode arrays
更新于2025-09-23 15:19:57