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oe1(光电查) - 科学论文

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?? 中文(中国)
  • [IEEE 2019 IEEE International Conference on Consumer Electronics - Asia (ICCE-Asia) - Bangkok, Thailand (2019.6.12-2019.6.14)] 2019 IEEE International Conference on Consumer Electronics - Asia (ICCE-Asia) - Development of Automated LED Light Compensation System for Lycopersicon Esculentum

    摘要: The cells in an organism emit different amounts of proteins according to their clinical state (healthy/pathological, for instance). The resulting proteomic pro?le can be used for early detection, diagnosis, and therapy planning. In this paper, we study the classi?cation of a proteomic sample from the point of view of an inverse problem with a joint Bayesian solution, called inversion-classi?cation. We propose a hierarchical physical forward model and present encouraging results from both simulation and clinical data.

    关键词: proteins,classi?cation algorithms,proteomics,Statistical signal processing,probability,liquid chromatography,mass spectrometry,selective reaction monitoring,inverse problems,mathematical modelling

    更新于2025-09-19 17:13:59

  • [IEEE 2019 16th International Conference on Electrical Engineering/Electronics, Computer, Telecommunications and Information Technology (ECTI-CON) - Pattaya, Chonburi, Thailand (2019.7.10-2019.7.13)] 2019 16th International Conference on Electrical Engineering/Electronics, Computer, Telecommunications and Information Technology (ECTI-CON) - The Designation of the Lightning Protection for the Photovoltaic Module by using the Protective Angle Method

    摘要: In this paper, a new and efficient methodology is proposed to quickly and precisely evaluate the power consumption and performance of wireless communication base-band systems implemented in field-programmable gate arrays (FPGAs). As the complexity of such systems is still growing, being able to estimate both power and performance of a design has become a major issue. FPGA devices constitute a promising technology in this highly constrained context. However, to respect their power budget, designers need to explore the design space very soon in the design process. This is performed prior to any implementation. Based on the innovative definition of a scenario, which enables comparison among wireless communication applications in a formal manner, each parameter can be evaluated to meet the power-performance tradeoff. In this paper, the proposed methodology is realized in two steps using a low-level characterization process and high-level system modeling. Another major contribution consists in considering components’ time activity to refine power estimations results. We demonstrate the effectiveness of the proposed methodology throughout several domain-specific use cases, with a focus on hardware base-band processing in the wireless communication domain. As compared with current low-level FPGAs vendor tools, an important speedup factor is obtained, and a maximal relative error lower than 5% is reached.

    关键词: system modelling,SystemC,Wireless communication,field programmable gate array,power consumption

    更新于2025-09-19 17:13:59

  • Combined Use of Terrestrial Laser Scanning and UAV Photogrammetry in Mapping Alpine Terrain

    摘要: Airborne and terrestrial laser scanning and close-range photogrammetry are frequently used for very high-resolution mapping of land surface. These techniques require a good strategy of mapping to provide full visibility of all areas otherwise the resulting data will contain areas with no data (data shadows). Especially, deglaciated rugged alpine terrain with abundant large boulders, vertical rock faces and polished roche-moutones surfaces complicated by poor accessibility for terrestrial mapping are still a challenge. In this paper, we present a novel methodological approach based on a combined use of terrestrial laser scanning (TLS) and close-range photogrammetry from an unmanned aerial vehicle (UAV) for generating a high-resolution point cloud and digital elevation model (DEM) of a complex alpine terrain. The approach is demonstrated using a small study area in the upper part of a deglaciated valley in the Tatry Mountains, Slovakia. The more accurate TLS point cloud was supplemented by the UAV point cloud in areas with insu?cient TLS data coverage. The accuracy of the iterative closest point adjustment of the UAV and TLS point clouds was in the order of several centimeters but standard deviation of the mutual orientation of TLS scans was in the order of millimeters. The generated high-resolution DEM was compared to SRTM DEM, TanDEM-X and national DMR3 DEM products con?rming an excellent applicability in a wide range of geomorphologic applications.

    关键词: terrestrial laser scanning,digital modelling,point cloud,UAV photogrammetry,alpine terrain

    更新于2025-09-19 17:13:59

  • Preheating and thermal behaviour of a rotating cylindrical workpiece in laser-assisted machining

    摘要: Laser-assisted machining is a widely used technique for preheating workpiece to reduce cutting forces and promote machinability in metal machining, thereby enhancing manufacturing quality and productivity. In setting laser-assisted machining parameters, the current practice typically relies on trial-and-error approaches. The uncertainties thereof could lead to adverse outcomes in product manufacturing, thus negating the potential benefits of this machining method. A clear understanding of workpiece thermal behaviour under laser spot heating is pivotal to developing a systematic basis for determining required preheating levels and optimised cutting variables for laser-assisted machining. In achieving this, the experimental methods are recognised to be largely impractical, if not tedious, due to instrument limitations and practicality of suitable non-intrusive measuring methods. Conversely, numerical methodologies do provide precise, flexible and cost-effective analytical options, warranting potential for insightful understanding on the transient thermal impact from laser preheating on rotating workpiece. Presenting such an investigation, this article presents a finite volume-based numerical simulation that examines and analyses the thermal response imparted by laser spot preheating on a rotating cylinder surface. On a rotating frame of reference using the ANSYS Fluent solver, the numerical model is formulated, accounting for transient heat conduction into the cylinder body and the combined convection and radiation loses from the cylinder surface. The model is comprehensively validated to ascertaining its high predictive accuracy and the applicability under reported laser-assisted machining operating conditions. The extensive parametric analyses carried out deliver clear insight into the dynamics of thermal penetration occurring within the workpiece due to laser spot pre-heating. This facilitates appropriate consideration of laser preheating intensity in relation to other operating variables to achieve necessary material softening depth at the workpiece surface prior to setting out on the subsequent machining process. Building upon the data generated, a practically simpler and cost-effective preheating parametric predictor is synthesised for laser-assisted machining using neural network principles incorporating the Levenberg–Marquardt algorithm. This predictive tool is trained and verified as a practical preheating guide for laser-assisted machining for a range of operating conditions.

    关键词: numerical thermal modelling,Laser-assisted machining,artificial neural network,validation,thermal treatment

    更新于2025-09-19 17:13:59

  • Acceleration of carbon ion beams by an ultraviolet laser under conditions relevant for ion fast ignition of inertial fusion

    摘要: The properties of carbon ion beams produced by a 100-kJ, 1-ps, KrF ultraviolet laser under conditions relevant for ion fast ignition (IFI) of DT fusion are numerically investigated using the 2D3V particle-in-cell code, and the possibility of achieving the ion beam parameters required for IFI is tested. The numerical simulations of carbon ion acceleration were carried out for ?at carbon targets of various thicknesses (LT) and for various laser beam apertures (dL) on the target, while the laser pulse duration and energy were ?xed. It was found that both the radiation pressure acceleration (RPA) mechanism and the sheath acceleration mechanism signi?cantly a?ects the characteristics of the ion beam, with the RPA dominating in the case of thicker targets (LT ~ 10–30 μm). The ion beam parameters depend to a signi?cant extent on the target thickness and the distance from the target. The mean and maximum ion energy decrease with the increase of LT from 3 μm to 30 μm, while the ion beam intensity, the beam energy ?uence and the total energy of the “useful part” of the ion beam (with an aperture ≤ 50 μm) reach maximum values at LT ~ 5–10 μm. For the optimal value of LT and a small distance x from the target (x ~ LT), the ion beam parameters are close to or higher than what is required for IFI. However, due to the angular divergence of the ion beam, the beam intensity and ?uence decrease with an increase in the distance from the target, and at x ≥ 0.5 mm the beam parameters are below the values required for fusion ignition. To reach these values, higher laser energies and/or more sophisticated schemes of ion acceleration are required.

    关键词: Ion sources,Accelerator Applications,Accelerator modelling and simulations

    更新于2025-09-19 17:13:59

  • [IEEE 2020 IEEE 33rd International Conference on Micro Electro Mechanical Systems (MEMS) - Vancouver, BC, Canada (2020.1.18-2020.1.22)] 2020 IEEE 33rd International Conference on Micro Electro Mechanical Systems (MEMS) - Acoustically Coupled Wideband RF Filters with Bandwidth Reconfigurablity Using Ferroelectric Aluminum Scandium Nitride Film

    摘要: The paper presents a novel technique based on extension of a general mathematical method of transfinite interpolation to solve an actual problem in the context of a heterogeneous volume modelling area. It deals with time-dependent changes to the volumetric material properties (material density, colour, and others) as a transformation of the volumetric material distributions in space-time accompanying geometric shape transformations such as metamorphosis. The main idea is to represent the geometry of both objects by scalar fields with distance properties, to establish in a higher-dimensional space a time gap during which the geometric transformation takes place, and to use these scalar fields to apply the new space-time transfinite interpolation to volumetric material attributes within this time gap. The proposed solution is analytical in its nature, does not require heavy numerical computations and can be used in real-time applications. Applications of this technique also include texturing and displacement mapping of time-variant surfaces, and parametric design of volumetric microstructures.

    关键词: Scalar field,heterogeneous volume modelling,transfinite interpolation,texturing,material distribution,volumetric metamorphosis

    更新于2025-09-19 17:13:59

  • In-Situ Plasma Monitoring during the Pulsed Laser Deposition of Ni60Ti40 Thin Films

    摘要: The properties of pulsed laser deposited of Ni60Ti40 shape memory thin films generated in various deposition conditions were investigated. In-situ plasma monitoring was implemented by means of space- and time-resolved optical emission spectroscopy, and ICCD fast camera imaging. Structural and chemical analyses were performed on the thin films using SEM, AFM, EDS, and XRD equipment. The deposition parameters influence on the chemical composition of the thin films was investigated. The peeled layer presented on DSC a solid-state transformation in a different transformation domain compared to the target properties. A fractal model was used to describe the dynamics of laser produced plasma through various non-differentiable functionalities. Through hydrodynamic type regimes, space-time homographic transformations were correlated with the global dynamics of the ablation plasmas. Spatial simultaneity of homographic transformation through a special SL(2R) invariance implies the description of plasma dynamics through Riccati type equations, establishing correlations with the optical emission spectroscopy measurements.

    关键词: thin films,in situ plasma monitoring,nitinol,pulsed laser deposition,fractal modelling,SL(2R) invariance,homographic transformations,Riccati equation

    更新于2025-09-19 17:13:59

  • The use of optical fibers as passageways for the scintillation light produced in CaF <sub/>2</sub> (Eu) powder in water for low-level tritiated water measurement

    摘要: A solid scintillation counting (SSC) system which uses the mixture of CaF2(Eu) powder and tritiated water inside the chamber room will be developed for the measurement of low-level tritiated water. However, the coincidence detection e?ciency and net count rate might be limited by the photon absorption in the chamber of the SSC detector. This paper discusses the feasibility of using light guide ?bers as the optical passageway in the chamber room by Geant4 simulation. The simulation results show that the performance of the detector can be improved by using wavelength-shifting ?bers as optical passageway in the chamber. The detector can maintain a 4.2% coincidence detection e?ciency at a 6 cm chamber thickness, and the detection limit can be as low as 0.47 Bq/mL under 10 min measurement. As a result, using wavelength-shifting ?bers as optical passageways in the chamber room of the SSC system is possible and e?ective.

    关键词: Radiation monitoring,Detector modelling and simulations I (interaction of radiation with matter, interaction of photons with matter, interaction of hadrons with matter, etc),Very low-energy charged particle detectors,Solid state detectors

    更新于2025-09-16 10:30:52

  • [IEEE 2019 International Conference on Electromagnetics in Advanced Applications (ICEAA) - Granada, Spain (2019.9.9-2019.9.13)] 2019 International Conference on Electromagnetics in Advanced Applications (ICEAA) - On the Techniques to Design 3D-Printable Arbitrarily Height-Modulated Substrate Integrated Waveguide Filters

    摘要: A novel modelling technique to design microwave 3D-printable ?lters based on arbitrarily height-modulated substrate integrated waveguides (SIW) is presented in this paper. In the literature, different topologies have been already employed to design ?lters based on SIW. Nevertheless, none of these solutions have analyzed the behavior of the modulation of the height of the ?lters. This is due to the dif?culty of manufacturing the prototypes with conventional procedures. In this paper, the techniques to design and manufacture these ?lters, provided with microstrip transitions for their validation, are presented.

    关键词: 3D-printing,simulations,?lter,modelling,substrate integrated waveguide (SIW)

    更新于2025-09-16 10:30:52

  • Study to improve the efficiency of c-Si material in photovoltaic power plant

    摘要: In the present communication, comparison between performance of photovoltaic module with and without duct has been carried out. Different input parameters (namely, ambient air temperature, solar radiation wind speed etc.) have been considered for IIT, Delhi campus. Further, thermal modelling has been derived for the c-Si photovoltaic (PV) module alone and PV module with duct. Different parameters like outlet air temperature from duct and cell temperature have been calculated through MATLAB coding. Due to integration of duct, 3.89% and 125.74% increase in electrical output and equivalent thermal energy have been found in comparison to stand-alone PV module.

    关键词: Power plant,Thermal modelling,Photovoltaic module,Equivalent thermal efficiency,Equivalent thermal energy

    更新于2025-09-16 10:30:52