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[IEEE 2019 IEEE 5th International Conference for Convergence in Technology (I2CT) - Bombay, India (2019.3.29-2019.3.31)] 2019 IEEE 5th International Conference for Convergence in Technology (I2CT) - Development of Embedded System for Monitoring of Life Test Setup of LED Lamp
摘要： Indian standard (IS 16102-2: 2017), specifies the life test and performance test methods and conditions, to categorize the self-ballasted LED lamps. This test process is being done with manual intervention with camera observation and digital timer. This paper proposes, the digital automation of entire life test setup process using embedded system. The entire test process is monitored and results are displayed in LCD. This gives accurate run time and life of LED lamp during the test. The information of lamp failure and completion of test is sent through mail to concerned person.
关键词： luminous flux intensity,Indian standard (IS 16102-2: 2017),LED,automation
更新于2025-09-23 15:21:01
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Study on the Microstructure and Properties of Al/Cu Laser Filled Solder Joint
摘要： Using IPG-YLS-4000 fiber laser to weld T2 copper plate and LY16 aluminum alloy plate, using Zn-10%Al flux cored wire as filler material, the microstructure of the joint was observed and analyzed by SEM and EDS, and the effects of laser power, welding speed and welding line energy on the mechanical properties of the joint were studied. The results show that the joints are mainly divided into copper side brazing area, weld center area and aluminum side fusion welding area. Among them, there are two interface reaction layers composed of intermetallic compound (IMC) in the copper side brazing area, the first layer is CuZn compound in the form of strip, and the second layer is Al2Cu phase in the form of shoot. The central area of the weld is mainly composed of massive α-Al phase and branched β-Zn phase. The tensile strength of the joint increases first and then decreases with the increase of laser power, welding speed and welding line energy. The thickness of IMC layer grows linearly with the increase of line energy. The best process parameters: when the laser power is 2200 W, the welding speed is 0.9 m/min, the welding line energy is 1446.67 J/cm, the IMC layer thickness is 10.11 μm, and the tensile strength reaches the maximum value, 252.6 MPa.
关键词： intermetallic compound,Al/Cu laser welding,microstructure,mechanical properties,Zn-10%Al flux cored wire
更新于2025-09-23 15:21:01
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Features of electromagnetic wave propagation in two- and three-layer cylindrical dielectric waveguides
摘要： Various characteristics of electromagnetic waves propagating in two- and three-layer open-dielectric waveguide structures of cylindrical shape are studied. Parameters of wave components in separate areas of the waveguide are considered. Electrodynamic characteristics and frequency dependencies for several values of layer dielectric permittivity obtained during the study are analyzed. The corresponding graphs of dependencies are presented. The dependencies of the power flux density of transverse magnetic (TM) waves in two- and three-layer waveguide structures in the absence of field dependence on azimuthal angle are considered.
关键词： dielectric waveguides,TM waves,power flux density,electromagnetic waves,cylindrical waveguides
更新于2025-09-23 15:21:01
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Pseudo-Source Parameters for Flares: Derivation, Implementation and Comparison
摘要： The Alberta Energy Regulator (AER) regulates Alberta’s oil and gas industry and has done extensive development of un-combusted and combusted sour gas release dispersion models with spreadsheet interfaces. Sour gas contains hydrogen sulphide (H2S) that is converted to sulphur dioxide (SO2) during combustion. The Energy Resources Conservation Board (ERCB), the predecessor of the AER, developed ERCBH2S to calculate emergency response and planning zones for accidental, un-combusted releases of H2S (ERCB, 2010) using SLAB. AERflare-incin is a regulatory tool for permitting routine and non-routine operations of sour gas flares and incinerators (AER, 2014) using the atmospheric dispersion modelling system known as AERMOD developed by the American Meteorological Society and United States Environmental Protection Agency (US EPA) Regulatory Model Improvement Committee.
关键词： momentum flux,buoyancy flux,pseudo-source parameters,AERMOD,flare modelling
更新于2025-09-23 15:19:57
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Magnetoa??optical specifications of Rosena??Morse quantum dot with screw dislocation
摘要： This is the first study to consider a quantum dot with screw dislocation that has Rosen-Morse (RM) confinement potential, generated by a GaAs/GaAlAs heterostructure. An external magnetic field and Aharonov-Bohm (AB) flux field were also applied on RM quantum dot (RMQD) in order to stave the effects of a screw dislocation defect. The combined effect of the screw dislocation defect, the external magnetic field, and AB flux field on the total refractive index changes (TRICs) and the total absorption coefficients (TACs) of RMQD are thus investigated. Cylindrical coordinates are used due to the direction of application of the torsion and the external fields, as well as due to the structure's symmetry. The effective mass approximation and tridiagonal matrix methods are used in order to obtain the subband energy spectra and electronic wave functions of RMQD. The nonlinear optical specifications of RMQD are checked using compact-density-matrix formalism within the framework of the iterative method. Reviews without screw dislocation are also carried out in order to be able to clarify the effects of a screw dislocation defect on the optical properties, and then, both cases are deliberated. This study is the first attempt to analyze the AB flux field for RMQD without screw dislocation. In the present study, the influences of a screw dislocation defect on RMQD's TRICs and TACs are probed by considering different values of the external magnetic field and AB flux field, and the ranges of corresponding parameters on the optimum of the structure are specified. Moreover, the study also elucidates how to rule out the effects of screw dislocation on optical specifications by means of the external fields. Despite a certain screw dislocation, the frequency range is determined where the structure behaves as if it is perfect (namely, without screw dislocation) for its optimum, which in turn is crucial for experimental applications.
关键词： quantum dot,magnetic field,screw dislocation,Aharonov-Bohm flux field,nonlinear optical properties
更新于2025-09-23 15:19:57
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Near-Field Radiative Heat Transfer between Dissimilar Materials Mediated by Coupled Surface Phonon- and Plasmon-Polaritons
摘要： Near-field radiative heat transfer (NFRHT) between dissimilar materials supporting surface polaritons in the infrared is of critical importance for applications such as photonic thermal rectification and near-field thermophotovoltaics. Here, we measure NFRHT between millimeter-size surfaces made of 6H-SiC and doped Si, respectively supporting surface phonon-polaritons (SPhPs) and surface plasmon-polaritons (SPPs) in the infrared, separated by a 150-nm-thick vacuum gap spacing maintained via SiO2 nanopillars. For purpose of comparison, measurements are also performed between two doped Si surfaces. The measured radiative flux is in good agreement with theoretical predictions based on fluctuational electrodynamics. A flux enhancement beyond the blackbody limit of ~ 8.2 is obtained for the SiC-Si sample, which is smaller than the enhancement for the Si-Si sample (~ 12.5) owing to the spectral mismatch of the SiC and Si light lines, and SPhP and SPP resonances. However, due to lower losses in SiC than Si and weaker SPhP-SPP coupling than SPP coupling, the near-field enhancement for the SiC-Si sample exhibits a more pronounced monochromatic behavior with a resonant flux that is ~ 5 times larger than the resonant flux for the Si-Si sample. This work demonstrates that it is possible to modulate NFRHT via surface polariton coupling, and will accelerate the development of energy conversion and thermal management devices capitalizing on the near-field effects of thermal radiation between dissimilar materials.
关键词： radiative flux measurement,doped silicon,near-field radiative heat transfer,dissimilar materials,coupled surface phonon- and plasmon-polaritons,silicon carbide
更新于2025-09-23 15:19:57
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Self-assembled nanorods in YBCO matrix a?? a computational study of their effects on critical current anisotropy
摘要： In order to understand how the doping with self-assembled nanorods of different sizes and concentrations as well as applied magnetic fields affect the critical current anisotropy in YBa2Cu3O7?x (YBCO) thin films close to YBCO c-axis, we present an extensive and systematic computational study done by molecular dynamics simulation. the simulations are also used to understand experimentally measured Jc(θ) curves for BaHfO3, BaZrO3 and BaSnO3 doped YBCO thin films with the help of nanorod parameters obtained from transmission electron microscopy measurements. our simulations reveal that the relation between applied and matching field plays a crucial role in the formation of Jc(θ)-peak around YBCO c-axis (c-peak) due to vortex-vortex interactions. We also find how different concentrations of different size nanorods effect the shape of the c-peak and explain how different features, such as double c-peak structures, arise. In addition to this, we have quantitatively explained that, even in an ideal superconductor, the overdoping of nanorods results in decrease of the critical current. our results can be widely used to understand and predict the critical current anisotropy of YBco thin films to improve and develop new pinscapes for various transport applications.
关键词： critical current anisotropy,molecular dynamics simulation,YBCO,flux pinning,self-assembled nanorods
更新于2025-09-23 15:19:57
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[IEEE 2020 IEEE Conference of Russian Young Researchers in Electrical and Electronic Engineering (EIConRus) - St. Petersburg and Moscow, Russia (2020.1.27-2020.1.30)] 2020 IEEE Conference of Russian Young Researchers in Electrical and Electronic Engineering (EIConRus) - Investigation of an UWB Antipodal Tapered Slot Antenna Element Based on Substrate Integrated Waveguide in an Antenna Array
摘要： In 2008, the first commercial wave farm came online in Portugal. As with other types of renewable energy, the electricity obtained from waves has the drawback of intermittency. Knowing a few hours ahead how much energy waves will hold can contribute to a better management of the electricity grid. In this work, three types of statistical models have been used to create up to 24-h forecasts of the zonal and meridional components of wave energy flux (WEF) levels at three directional buoys located off the coast in the Bay of Biscay. Each model’s performance has been compared at a 95% confidence level with the simplest prediction (persistence of levels), along with the forecasts provided by the physics-based WAve Modeling (WAM) wave model at the nearest grid point. The results indicate that for forecasting horizons between 3 and roughly 16 h ahead, the statistical models built on random forests (RFs) outperform the rest, including WAM and persistence.
关键词： Applied physics,forecasting,random forests (RFs),wave energy flux (WEF),fluid mechanics,Bay of Biscay
更新于2025-09-23 15:19:57
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A novel flux mapping system for high-flux solar simulators based on the indirect method
摘要： It is an important and challenging work to measure the energy flux density distribution of the concentrated radiation during the concentrating solar power applications. In order to evaluate the performance of a multi-lamps high-flux solar simulator, a novel flux mapping system based on the indirect method has been developed. It features two Lambertian targets. One is a stationary water-cooled Lambertian target where there is a circular hole in the center used to install a flux sensor. The other is a movable Lambertian target used to cover the flux sensor when shooting the concentrated light beam image. This kind of design can obtain the gray value of flux sensor region directly and does not require the interpolation in the sensor-influencing area. The design theory and principle, the hardware implementation and the experimental validation of this flux mapping system have been presented in detail. The repeatability experiments and the error analyses showed that the total relative errors of this flux mapping system were ± 8.1% with a repeatability of 1.1%, and ± 8.5% with a repeatability of 2.7%, for evaluating the flux and the total radiant power, respectively.
关键词： The indirect method,Concentrated solar radiation,High-flux solar simulator,Flux mapping system
更新于2025-09-19 17:15:36
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Separation of optical angular momentum flux
摘要： We present an approach to separation of the angular momentum (AM) flux of monochromatic light into its spin and orbital parts based on symmetrized AM tensor. When considering the AM flux for a light beam through its cross section and that for an outgoing wave through a spherical surface in the far-field zone, the separation gives the desired results: the spin/orbital AM flux equals the integral of spin/orbital AM density times some weighting factor accounting for energy flux. When applied to Bessel beams, the obtained spin and orbital AM fluxes are exact the same as those given by the paper [2014 New J. Phys. 16 093037] based on the canonical AM tensor separation. Furthermore, from the spin AM flux integral, the divergence-free spin AM tensor can be identified. We define the orbital AM tensor to be the difference between the total AM tensor and the spin AM tensor. Since the total AM tensor is divergence-free, the integral for either spin and orbital AM flux, can be made on any closed surface.
关键词： symmetrized AM tensor,angular momentum flux,spin AM tensor
更新于2025-09-19 17:15:36