- 标题
- 摘要
- 关键词
- 实验方案
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The Influence of Laser Modification on a Composite Substrate and the Resistance of Thin Layers Created Using the PVD Process
摘要： For physical vapor deposition (PVD) technology, cleaning a substrate is one of the key preliminary processes before depositing the metal layer. In this article, we present the results of research on the modification of a textile composite substrate using laser technology and its influence on the surface resistance of silver structures intended for use in wearable electronics. As a result of the substrate modification, the resistance of the layers increased as compared with the structures produced on an unmodified substrate. An experimental planning technique was used to optimize the laser modification process.
关键词： wearable electronics,textronics,design of experiments,physical vapor deposition,laser modification,PVD
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) - Study of Open-Circuit Voltage in CdTe/MgCdTe Double-Heterostructure Solar Cells with Different Hole Contacts
摘要： Model predictive control (MPC) has been widely advocated as a design strategy for many aspects of industrial electronics. The methodology has been strongly promoted by some researchers but has also attracted criticism from others. In this context, the purpose of this paper is twofold. First, we show that many existing and popular control strategies, including finite set MPC and linear controllers [proportional integral, proportional resonant (PR)], can be viewed as special cases of MPC. Second, we show that the predictive control framework allows one to embellish these classical control architectures with novel features and to design new and advanced control architectures to address various challenges posed by power electronics applications. The findings of the paper are supported by a practical example of designing of a novel form of PR controller with superior tracking performance and delay compensation, confirmed via simulation and experiments.
关键词： model predictive control (MPC),Control design,dc–ac power converters,pulsewidth modulation inverters,current control
更新于2025-09-23 15:19:57
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Electromagnetic Physical Numerical Modeling of a GaN Distributed Transferred Electron Devicea??Based Planar Waveguide THz Oscillator
摘要： The radio frequency (RF) operation of a planar waveguide THz oscillator based on the distributed transferred electron device (DTED) is theoretically investigated by means of 2-D time-domain numerical physical modeling based on the self-consistent solution of the Maxwell and free electron energy-momentum macroscopic transport equations.
关键词： circuit design analysis,distributed transferred electron device (DTED),2-D time-domain electromagnetic physical numerical modeling,planar waveguide THz oscillator
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) - Inverse Photonic Design of Functional Elements That Focus Bloch Surface Waves
摘要： Bloch surface waves (BSWs) are surface states excited at the interface between a one-dimensional dielectric photonic crystal (1D-PC) and some ambient material. They are promising alternatives to propagating surface plasmon polaritons thanks to their much longer propagation lengths (up to thousand times the wavelength) that is not limited by absorption and the opportunity to excite them in both polarizations. They are currently considered for multiple applications in integrated optical systems or for sensing devices [1]. To control the propagation of BSWs, a structured functional layer is deposited on top of the 1D-PC. It consists of a thin dielectric layer with a desired shape that controls locally the dispersion relation of the BSW. This allows to implement, in general, optical elements with functions on demand. However, a severe limitation is the finite index contrast to be induced with the functional layer. For typical combinations of material and geometries, an index contrast only in the order of ~ 0.1 is achieved. This is insufficient to tightly focus a BSW with elements perceived by a rational design approach, e.g. with lens-like elements [2]. To solve this problem, we apply here methods developed in the context of computational photonic material design to perceive functional elements that focus BSWs highly efficiently [3]. We basically aim to solve the inverse problem. Computationally, we rely on a finite-difference frequency method as the Maxwell solver. To identify suitable structures, we discretize a finite spatial domain (typically in the order of 40μm x 10μm) where each pixel either is or is not covered by the functional layer. By systematically flipping each pixel, we can optimize structures that can focus the BSW into a predefined spatial domain. For a spatial domain directly behind the element, the BSW can be focused even below half its wavelength (a selected example is shown in Fig. 1a). To verify the findings, we fabricated the respective structures and measured the optical near-fields above them (a selected example is shown in Fig. 1b). The comparison between the simulation and the measurement shows an impressive agreement and allows to verify the ability to tightly focus the BSWs (Fig. 1c). This work introduces a new computational framework to design functional elements that can be used to control the propagation of BSWs and verifies it experimentally. Our approach is suitable for other material platforms where the limited index contrast is an obstacle to control the propagation of some waves. The elements we have studied can find immediate application in lab-on-chip systems where tightly focused BSWs interact with materials carried in fluidic channels to perform spectroscopic measurements.
关键词： functional elements,Bloch surface waves,photonic design,focusing,computational framework
更新于2025-09-23 15:19:57
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Hybrid Inexact BCD for Coupled Structured Matrix Factorization in Hyperspectral Super-Resolution
摘要： A simple quantization scheme is proposed to adjust separately the amplitudes and phases of signals in a codebook-based Transmit Beamforming (TBF) scheme. The proposed quantization scheme is valid for both desired signal power maximization (egoistic TBF) and co-channel interference mitigation (altruistic TBF), and does not require an exhaustive search to find the optimal TBF vector. Performance results are presented when variable numbers of bits for amplitude and phase feedback resolutions are used for both egoistic and altruistic TBF schemes.
关键词： transmit beamforming,Codebook design,interference mitigation,limited feedback terms,separate quantization
更新于2025-09-23 15:19:57
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Design issues adumbrate conclusions on LED-mediated bycatch risk reduction of cetaceans and turtles in fishing nets: A comment on Bielli et al. (2020)
摘要： Worldwide, bycatch is one of the biggest threat to the long-term viability of cetaceans and turtles (Reeves et al., 2013; Wallace et al., 2013), or marine megafauna in general (Lewison et al., 2004). Reducing marine megafauna bycatch is urgent: Bielli et al. (2020) reported a decreased risk of bycatch for cetaceans and turtles by small-scale fisheries targeting elasmobranchs in Peruvian waters when green visible spectrum light emitting diodes (LEDs) were added on fishing nets. To estimate the causal effect of LEDs on bycatch, some nets had LEDs (treatment) and some nets had none (control). Due to intrinsic difficulties of collecting relevant data in realistic settings while not overburdening fishermen with additional constraints, nets with LEDs were, on average, shorter than nets without. The ratio of effort (in km of net soaked per day) in treatment versus control amounts to 40%. Because of this systematic difference between treatment and control in the experimental design, less bycatch (in absolute numbers) is expected in treatment than in control conditions. This may be taken into account in the statistical analysis of data. However, such a design results in treatment and effort being intrinsically confounded: estimating the causal effect of LEDs on bycatch with these data is problematic as any estimated effect will be model-dependent (Rubin, 2008).
关键词： Causal analysis,Marine megafauna,Design of experiments,Covariate overlap,Bycatch
更新于2025-09-23 15:19:57
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First Report of Chenodeoxycholic Acida??Substituted Dyes Improving the Dye Monolayer Quality in Dyea??Sensitized Solar Cells
摘要： Chenodeoxycholic acid (CDCA) is the most used antiaggregation additive in dye-sensitized solar cells since its introduction to the field in 1993. However, effective suppression of dye aggregation comes at the cost of reduced dye loading, a lower open-circuit voltage, and limited control of dye/additive distribution when cosensitizing with free CDCA. To combat this, herein, a novel dye design concept that uses the covalent attachment of a CDCA moiety to triarylamine sensitizers is reported. The CDCA substituents do not affect the photophysical or electrochemical properties of the sensitizers but have a positive effect on the photovoltaic performance with [Cu(tmby)2](TFSI)1/2 electrolyte (tmby = 4,4',6,6'-tetramethyl-2,2'-bipyridine, TFSI = bis(trifluoromethanesulfonyl)imide). By ensuring a one-to-one ratio of dye and CDCA, paired with isotropic distributions of each component, this approach results in a higher-quality dye monolayer. Compared with the reference system, the novel approach reported herein gives a higher open-circuit voltage and power conversion efficiency (PCE). The best device is fabricated with the dye C6–CDCA, delivering a PCE of 6.84% (8 μm TiO2, 1 mM CDCA, JSC = 8.64 mA cm?2, VOC = 1007 mV, and FF = 0.77).
关键词： dye design,dye distributions,sensitizer quantum efficiencies,chenodeoxycholic acid,antiaggregation
更新于2025-09-23 15:19:57
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[IEEE 2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall) - Xiamen, China (2019.12.17-2019.12.20)] 2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall) - The Full-space Bessel Beam Modulator Based on Pancharatnam-Berry Metasurface
摘要： Time-domain channel characterization (TCC) for de-embedding of an asymmetric fixture is introduced. Two design criteria for the design of a 2x-thru are proposed. Error sensitivity regarding a small error in the S-parameters of the 1x-fixture is analyzed with an insertion loss error-coefficient and a return loss error-coefficient. The TCC procedure, including proposed design criteria and error sensitivity, is also introduced to reduce the error in the TCC application. Three different 2x-thru structures are investigated for the verification of the two proposed design criteria and analyzed for error sensitivity. Test fixtures on a printed circuit boards are fabricated for the experimental verification.
关键词： return loss error-coefficient (RLEC),design criteria,De-embedding,error-coefficient,time-domain channel characterization (TCC),insertion loss error-coefficient (ILEC),error sensitivity
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) - Efficient Heterojunction Thin Film CdSe Solar Cells Deposited Using Thermal Evaporation
摘要： This paper considers an energy-limited cognitive relay network, where a secondary transmitter (ST) assists to forward the traf?c from a primary transmitter (PT) to a primary receiver (PR), in exchange for serving its own secondary receiver (SR) in the same frequency. The multiple-antenna ST is assumed to be energy-constrained and powered by both information ?ow from source (PT) and dedicated energy streams from destinations (PR and SR), which is called a destination-aided wireless power transfer (DWPT) scheme. Then, the relay processing matrix, cognitive beamforming vector, and power splitter are jointly designed to maximize the rate of secondary users under the energy causality constraint and the constraint that the demanded rate of primary users is satis?ed. For the perfect channel state information (CSI) case, by adopting the semi-de?nite relax technique and the Charnes–Cooper transformation, the global optimal solution is given. To reduce the complexity, matrix decomposition, zero forcing scheme, and dual method are jointly employed to derive a suboptimal solution. For the imperfect CSI case, the S-procedure is used to transform the worst case robust problem into a tractable semi-de?nite program. Simulation results reveal that our proposed DWPT scheme is greatly preferred for both perfect and imperfect CSI cases when ST is close to PR/SR.
关键词： cognitive relay networks,power splitting,Wireless power transfer,semi-de?nite program,beamforming design
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR) - Long Beach, CA, USA (2019.6.15-2019.6.20)] 2019 IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR) - Joint Manifold Diffusion for Combining Predictions on Decoupled Observations
摘要： A simple quantization scheme is proposed to adjust separately the amplitudes and phases of signals in a codebook-based Transmit Beamforming (TBF) scheme. The proposed quantization scheme is valid for both desired signal power maximization (egoistic TBF) and co-channel interference mitigation (altruistic TBF), and does not require an exhaustive search to find the optimal TBF vector. Performance results are presented when variable numbers of bits for amplitude and phase feedback resolutions are used for both egoistic and altruistic TBF schemes.
关键词： Codebook design,interference mitigation,limited feedback terms,separate quantization,transmit beamforming
更新于2025-09-23 15:19:57