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- 2019
- Distributed optical fiber sensing
- Optical frequency domain reflection
- Polynomial regression algorithm
- Nonlinear tuning compensation
- Optoelectronic Information Science and Engineering
- Hebei University of Technology
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[IEEE 2019 21st International Conference on Transparent Optical Networks (ICTON) - Angers, France (2019.7.9-2019.7.13)] 2019 21st International Conference on Transparent Optical Networks (ICTON) - The Influence of the Excited State (ES) Lasing in Quantum Dot-in-a-Well (QDWELL) Structure on the QDWELL Laser Performance in Optical Communication Systems
摘要： AC voltage regulation is required in both the domestic and industrial sectors to avoid undesired effects from random voltage variations of the power supply. The paper introduces an ac voltage stabilizer/converter (ACVS) that is based on a controllable autotransformer technology. The proposed ACVS offers a specified strategy of voltage regulation, less harmonics, and low cost. The paper explains the operating principle of the ACVS and derives its nonlinear mathematical model. To ensure the desired performance of the ACVS while it is subject to uncertain input voltage and load variations, an optimal control strategy is designed. It is achieved via transforming the ACVS model extending with fictive axis emulation into a rotating reference frame and the linearization of the model via specific orientation of the reference frame and introducing a linear control action. Operation of the ACVS is simulated under different disturbances due to load and grid voltage changes, and compared to voltage stabilization with application of I and PI controllers. Experimental results are presented to demonstrate the voltage regulation technology.
关键词： AC–AC power conversion,electric variables control,linear-quadratic control,power quality,voltage control
更新于2025-09-19 17:13:59
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Investigation of electrical values of low-efficiency dye-sensitized solar cells (DSSCs)
摘要： Indium-tin-oxide (ITO)/density (d)- titanium dioxide (TiO2)/nonporous (nonp)-TiO2 is a TiO2-based bilayer photoanode. These photoanodes coated for dye-sensitized solar cells (DSSCs) were with nonp-TiO2 surface and had very thick ITO layer. DSSCs were fabricated with these photoanodes. After their current density-voltage (J-V) were analyzed, ?t was seen that they were low efficiency and the shape of their J-V curve was linear line instead of rectangle. In this study, it was examined the relationship between the dark current (IDC), the series resistance (Rs) and the shunt resistance (Rsh) were examined for evaluating the fill factor (FF) of low-efficiency DSSCs because of the photoanodes with nonp-TiO2 surfaces and very thick ITO for contact layer. It was seen in the J-V graph of DSSCs which had low FF value due to their IDC and low Rsh. The J-V graph of low-efficiency DSSCs is linear due to their low Rsh and high Rs values. Moreover, the too thick ITO layer decreases the resistance of photoanodes; however, electrons in these photoanodes can not efficiently transferred to external circuit from ITO contact layer of DSSCs.
关键词： Fill factor,Linear,Nonporous,Back electron,Low-efficiency,Dark current,Cell resistance
更新于2025-09-19 17:13:59
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Optimal operational strategy for an offgrid hybrid hydrogen/electricity refueling station powered by solar photovoltaics
摘要： This study introduces a novel concept to provide both electric charging and hydrogen refueling at the same location. A hybrid hydrogen/electricity refueling station (HERS) powered only by solar photovoltaics in a remote area without access to the electrical grid is proposed. This station provides electricity for battery electric vehicles (BEVs) and simultaneously produces hydrogen for hydrogen fuel cell vehicles (HFCVs). Owing to the variability of PV power output and electricity price, electricity and hydrogen demands, this study investigates a possible operational strategy for the offgrid HERS. The objective is to propose optimal operational strategies for such a station to maximize profits by selling electricity and hydrogen to owners of both BEVs and HFCVs. Failure to supply electricity and hydrogen is treated as a penalty in the target function. The scenario-based stochastic method is adopted for this uncertainty modeling, and the conditional value-at-risk is also considered for evaluating the financial risks. The results reveal that 1) the proposed HERS can simultaneously supply the demands of the BEVs and HFCVs and 2) the behavior of HERS (providing energy to BEVs or HFCVs) is determined by several major factors, namely, electricity and hydrogen prices, and the penalty coefficients.
关键词： Conditional value-at-risk,Electrical vehicles,Operational strategy,Hydrogen-fueled vehicles,Hybrid hydrogen/electricity refueling station,Solar photovoltaics,Mixed-integer linear programming
更新于2025-09-19 17:13:59
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Industrial Applications of Nanomaterials || Nanomaterials-based UV photodetectors
摘要： Photodetectors are essential elements applied in video imaging, optical communications, biomedical imaging, security, night-vision, gas sensing, and motion detection, which possess the ability to transform light into electrical signals precisely. As the scale and diversity of application areas are growing, the need for innovative photodetection platform technologies with higher performance in terms of speed, efficiency or wavelength range, as well as material flexibility, transparency, and complementary metal-oxide-semiconductor (CMOS) integrability, is becoming more critical. In the past decades, extensive efforts have been devoted to explore the next generation of photodetector materials, such as In2Te3, ZnO, and GaN, with low noise, high photosensitivity, and good stability. However, many of these novel photodetector materials still suffer from limited photocurrent and photoresponse speed.
关键词： Nanomaterials,Schottky contacts,photoconductive gain,photodetection mechanism,photoresistors,linear dynamic range,responsivity,external quantum efficiency,photodiodes,specific detectivity,UV photodetectors
更新于2025-09-19 17:13:59
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[IEEE 2019 7th International Electrical Engineering Congress (iEECON) - Hua Hin, Thailand (2019.3.6-2019.3.8)] 2019 7th International Electrical Engineering Congress (iEECON) - Theoretical Study of Multi-stacked GaSb/GaAs Quantum Dot Solar Cells
摘要： In this paper, distributed time-varying formation (TVF) control problems for general linear swarm systems with switching interaction topologies are investigated using an adaptive dynamic protocol. First, a TVF control protocol for switching interaction topologies is constructed using the states of neighboring agents. In the protocol, an adaptive controller that employs gain scheduling technique is provided to estimate the coupling weights among agents. Compared with the previous studies on formation control, the desired formation can be specified by piecewise continuously time-varying differentiable vectors, the interaction topology can be switching, and the disadvantage of requiring global information of the interaction topologies is removed in this paper. Then, an algorithm including a feasible formation condition is proposed to determine the gain matrices of the distributed adaptive formation protocol by solving a linear matrix inequality for swarm systems with switching interaction topologies. Moreover, under the designed distributed adaptive formation protocol, sufficient condition for general linear swarm systems with switching interaction topologies to achieve the given TVF is derived using the Lyapunov theory. Finally, numerical simulations are presented to demonstrate the obtained results.
关键词： swarm systems,Distributed adaptive protocol,time-varying formation,switching interaction topology,general linear dynamics
更新于2025-09-19 17:13:59
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On the preservers of maximally entangled states
摘要： We characterize the linear maps that preserve maximally entangled states in L(X ?Y) in the case where dim(X ) divides dim(Y).
关键词： Maximally entangled states,Projective space,Linear preservers
更新于2025-09-19 17:13:59
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[IEEE 2019 21st International Conference on Transparent Optical Networks (ICTON) - Angers, France (2019.7.9-2019.7.13)] 2019 21st International Conference on Transparent Optical Networks (ICTON) - Plasmonic Waveguides Co-Integrated with Si <sub/>3</sub> N <sub/>4</sub> Waveguide Platform for Integrated Biosensors
摘要： This paper presents a placement algorithm for fault location observability using phasor measurement units (PMUs) in the presence or absence of zero injection buses. The problem is formulated as a binary semidefinite programming (BSDP) model with binary decision variables, minimizing a linear objective function subject to linear matrix inequality (LMI) observability constraints. The model is extended to take into account the unavailability or limited capacity of communication links at some PMU installation buses. The BSDP problem is solved using an outer approximation scheme based on binary integer linear programming. The method is illustrated with a 6-bus test system. Numerical simulations are conducted on the IEEE 14-, 30-, and 57-bus standard test systems to verify the effectiveness of the proposed method.
关键词： semidefinite programming,phasor measurement unit,linear matrix inequality,Fault location observability,synchronized phasor measurements
更新于2025-09-19 17:13:59
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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) - Class F-C Power Amplifier with 2nd Harmonic Control at the Input
摘要： Currently, self-healing is one of the most important functions in the smart grid. Meanwhile, fault detection, isolation, and restoration of feeder automation systems dominate the self-healing function in power distribution systems. The steps of the aforementioned function depend on the fault ?ag status of the feeder terminal unit. The conditions for setting this ?ag are judged by the feeder terminal unit overcurrent detecting curve. This paper found an ef?cient approach to calculate this curve via a half-interval method. Versatile application software with the curve plotting capability was also developed and deployed on the web server of the information-management department of Taiwan Power Company and is running successfully.
关键词： piecewise linear approximation,power distribution protection,IEEE standards,fault currents,Computer aided analysis
更新于2025-09-19 17:13:59
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An assessment study of evaporation rate models on a water basin with floating photovoltaic plants
摘要： Under the general topic of the impact of floating photovoltaics (FPVs) systems on water basins, the present study aims to model and analyze the effect of FPVs on the evaporation rate of water surfaces. The estimation of the evaporation of the water surface of a basin is usually calculated using mathematical evaporation models that require knowledge of some parameters (ie, solar radiation, humidity, air temperature, water temperature, and wind velocity). Thus, in the first section of this study, some evaporative models (EVM) for free water basin have been examined to evaluate which are the environmental variables used. On the basis of this analysis, new numerical models for the calculation of the daily evaporation rate have been developed using the design of experiments (DoE) method (three models) and the linear regression method (two models). The results of the developed models have been compared with the experimental measurements carried out by an evaporimeter; such comparison has highlighted the robustness of the proposed numerical models. Moreover, for estimating the evaporation rate in water basins partially covered by FPVs, further three numerical methods are proposed. Finally, the evaporation rates, arising by the installation of different typology of FPVs on water basins, have been evaluated as function of the energy balance on the water surface. It is possible to highlight that the amount of evaporated water depends not only on the percentage of surface covered but also on the characteristics of floating systems. Covering only 30% of the surface of a basin, it is possible to obtain up to 49% reduction in evaporation.
关键词： evaporation rate,linear regression,energy system,DoE methods,renewable energy,floating photovoltaics
更新于2025-09-19 17:13:59
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[IEEE 2019 Workshop on Recent Advances in Photonics (WRAP) - Guwahati, India (2019.12.13-2019.12.14)] 2019 Workshop on Recent Advances in Photonics (WRAP) - Study of temperature and hydrostatic pressure effect on SHG associated with the excitonic system in an InN Quantum dot
摘要： A key problem in wireless mesh networks is forwarding packets to/from one or more gateways with connectivity to the Internet. In this respect, a short link schedule, which determines the transmission time of links, is critical. To date, existing link schedulers do not consider routers that incorporate advances in multiple input multiple output communications, i.e., interference cancellation and spatial multiplexing. In particular, these routers are able to transmit or receive distinct packets on all their links concurrently as well as deliver multiple packets to a neighbor simultaneously. To this end, we consider the problem of deriving a time division multiple access schedule that forwards packets to their respective destination quickly. We ?rst consider the personalized broadcast problem, which assumes a single gateway and present Algo-PB, a solution that produces a schedule that is within 34.5% of the lower bound, and is 45.5% shorter than those computed by the state-of-the-art algorithms. We then extend the problem to consider multiple gateways. This so-called forest construction problem is modeled as an integer linear program (ILP). We then outline Algo-FC, a novel heuristic that generates a balanced forest by repeatedly picking a node from the heaviest tree and migrating it to another tree if doing so reduces the overall load. Experiment results show that the resulting forest generated by Algo-FC is within 9.1% of the ILP solution.
关键词： Link scheduler,multiple gateways,balanced tree,NP-complete,integer linear program (ILP)
更新于2025-09-19 17:13:59