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[IEEE 2019 5th International Conference on Advances in Electrical Engineering (ICAEE) - Dhaka, Bangladesh (2019.9.26-2019.9.28)] 2019 5th International Conference on Advances in Electrical Engineering (ICAEE) - Modeling and Simulation of Highly Efficient Single Junction GaInP Solar Cell
摘要： The Sentinel-1A is the first of two satellites that composes the Sentinel-1 radar mission. Both satellites operate a C-band synthetic aperture radar (SAR) system to give continuity to the European SAR program. SAR is a flexible sensor able to fulfil users/applications requirements in terms of resolution and coverage thanks to different operational modes and polarizations. With the in-orbit availability of very-high-resolution X-band SAR sensors, the Sentinel-1 satellites have been designed to achieve wide coverage at medium to high resolution. The interferometric wide swath (IWS) mode implemented with the terrain observation with progressive scan (TOPS) technique is the standard acquisition mode over European waters and land masses. IWS in dual-polarization (VV/VH) combination offers 250-km swath at 5 m × 20 m (range × azimuth) spatial resolution. These specifications are in line with the needs of the European Maritime and Security Agency (EMSA) for oil spill and ship detection applications included in the CleanSeaNet program. The main goals of this paper are: assessment of medium-to-high-resolution C-band Sentinel-1 data with very-high-resolution X-band TerraSAR-X data for maritime targets detection; synergetic use of multiplatforms satellite SAR data for target features extraction; evaluation of polarimetric target detectors for the available co-polarization and cross-polarization Sentinel-1A IWS VV/VH products. The objectives are achieved by means of real, almost coincident C-band and X-band SAR data acquired by Sentinel-1A and TerraSAR-X satellites over Gulf of Naples and Catania (South Italy). Furthermore, the obtained results are supported by recorded ground truth vessel reports via terrestrial automatic identification system (AIS) stations located in the area.
关键词： multipolarization,targets detection,Multifrequency,synthetic aperture radar (SAR)
更新于2025-09-19 17:13:59
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Analysis of electromagnetic pulses generation from laser coupling with polymer targets: Effect of metal content in target
摘要： Powerful lasers interacting with solid targets can generate intense electromagnetic pulses (EMPs). In this study, EMPs produced by a pulsed laser (1 ps, 100 J) shooting at CH targets doped with different titanium (Ti) contents at the XG-III laser facility are measured and analyzed. The results demonstrate that the intensity of EMPs first increases with Ti doping content from 1% to 7% and then decreases. The electron spectra show that EMP emission is closely related to the hot electrons ejected from the target surface, which is confirmed by an analysis based on the target–holder–ground equivalent antenna model. The conclusions of this study provide a new approach to achieve tunable EMP radiation by adjusting the metal content of solid targets, and will also help in understanding the mechanism of EMP generation and ejection of hot electrons during laser coupling with targets.
关键词： laser coupling,hot electrons,polymer targets,electromagnetic pulses,metal content
更新于2025-09-19 17:13:59
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A fluorescent plasmonic biochip assay for multiplex screening of diagnostic serum antibody targets in human Lyme disease
摘要： Lyme disease (LD) diagnosis using the current two-tier algorithm is constrained by low sensitivity for early-stage infection and ambiguity in determining treatment response. We recently developed a protein microarray biochip that measures diagnostic serum antibody targets using grating-coupled fluorescent plasmonics (GC-FP) technology. This strategy requires microliters of blood serum to enable multiplexed biomarker screening on a compact surface and generates quantitative results that can be further processed for diagnostic scoring. The GC-FP biochip was used to detect serum antibodies in patients with active and convalescent LD, as well as various negative controls. We hypothesized that the quantitative, high-sensitivity attributes of the GC-FP approach permit: 1) screening of antibody targets predictive for LD status, and 2) development a diagnostic algorithm that is more sensitive, specific, and informative than the standard ELISA and Western blot assays. Notably, our findings led to a diagnostic algorithm that may be more sensitive than the current standard for detecting early LD, while maintaining 100% specificity. We further show that analysis of relative antibody levels to predict disease status, such as in acute and convalescent stages of infection, is possible with a highly sensitive and quantitative platform like GC-FP. The results from this study add to the urgent conversation regarding better diagnostic strategies and more effective treatment for patients affected by tick-borne disease.
关键词： Lyme disease,grating-coupled fluorescent plasmonics (GC-FP) technology,diagnostic serum antibody targets,multiplex screening,fluorescent plasmonic biochip assay
更新于2025-09-19 17:13:59
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A Complex for Diagnostics of Laser Radiation of Semiconductor Targets Excited by a High-Frequency-Modulated Electron Beam
摘要： A complex of equipment for diagnosing the parameters of laser radiation of semiconductor targets, which are excited by high-frequency-modulated electron-beam pulses, is described. The ability to control the shape and duration of laser radiation in the picosecond range via high-frequency modulation of an accelerating-voltage pulse was demonstrated experimentally. A train of laser-radiation pulses with a maximum intensity of up to 2 × 107 W/cm2 was obtained on a cadmium sulfide target (λ = 525 nm).
关键词： picosecond range,cadmium sulfide,semiconductor targets,high-frequency-modulated electron-beam pulses,laser radiation
更新于2025-09-16 10:30:52
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Characteristics of quasi-unipolar electromagnetic pulses formed in the interaction of high-power laser pulses with nanoscale targets
摘要： A new method is suggested for generating quasi-unipolar electromagnetic IR and terahertz pulses. The method is based on synchronous acceleration of electrons combined to a dense bunch with a charge of up to several tens nanocoulombs, which are forced out from a nanoscale target under an action of a high-power, sharp-leading edge laser pulse. The electromagnetic bunch moving in a field of laser radiation can generate high-power electromagnetic pulses with various spectral composition including terahertz and IR ranges. A physical mechanism underlying the formation of generated quasi-unipolar pulses of electromagnetic radiation is determined and numerically studied. The pulse characteristics are found by numerical simulation, such as amplitude and duration dependences on the angle between the pulse propagation direction and laser beam axis. It is established that in modern laser installations, the amplitudes of quasi-unipolar pulses may reach relativistic values. Reflection of a unipolar pulse from an ideally reflecting surface is numerically analysed. It is shown that the pulse retains its unipolar profile in this case.
关键词： nanoscale targets,generation of terahertz and IR radiation,interaction of high-power laser pulses with matter,electron acceleration by laser pulses
更新于2025-09-16 10:30:52
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Undersea Target Reconstruction Based on Coupled Laplacian-of-Gaussian and Minimum Gradient Support Regularizations
摘要： In this paper, a novel inversion method is proposed to recover the sharp boundary of blocky targets buried beneath the seabed with conductivities different from that of the background environment. This method is implemented by combining the Laplacian-of-Gaussian (LoG) function with minimum gradient support (MGS) regularization. A two-stage inversion strategy is introduced to obtain stable and sharp boundary inversion results. We first use the LoG operator in 3D space to obtain the profile of the target and then switch to LoG-MGS coupled regularized inversion to obtain the sharp boundary of the target. It is crucial to choose an appropriate regularization parameter adjustment strategy. We use a bounded function to adjust the regularization parameters during the inversion, which can balance the observation information and the a priori information in a reasonable interval. Theoretical analysis and numerical simulations are conducted and the recovered results demonstrate that the proposed inversion method has a better performance in recovering blocky targets than canonical regularization terms.
关键词： LoG-MGS coupled regularization,inversion,Block targets,sharp boundary
更新于2025-09-16 10:30:52
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Characterization of plasma emission in the 1-6?nm band from laser-irradiated cryogenic xenon targets
摘要： We present measurements from laser-produced plasmas generated using cryogenic Xe targets and quantify the emission characteristics in the soft x-ray region (1 to 6 nm). The system is based on a LN2-cooled rotating drum, which allows for a high repetition rate, and Nd:YAG laser systems with energies up to 325 mJ on-target with pulse lengths of 130 ps, 600 ps, or 6.5 ns. High resolution spectra are measured using a grazing incidence spectrometer, and we present the first quantitative conversion efficiency (CE) measurements for Xe in this range. Data show CE values up to ～1% at 6 nm and ～0.08% at 1.5 nm (for 2% bandwidth and 2π solid angle), and there are lower limits on the required laser intensities and energies on target to achieve these efficiencies. In addition, the emission spot size is directly measured at 2 nm (620 eV) using a point-projection slit imaging method, with optimized emission spot sizes of ～20 μm.
关键词： soft x-ray,laser-produced plasmas,conversion efficiency,emission spot size,cryogenic Xe targets
更新于2025-09-16 10:30:52
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Simultaneous 3-D Surface Profiling of Multiple Targets by Repetition Rate Scanning of a Single Femtosecond Laser
摘要： We present an integrated scheme of 3-D surface profile measurements made at multiple sites concurrently by employing only a single fiber femtosecond laser as the common light source of low coherence scanning interferometry. This versatile use of an ultrashort mode-locked laser is enabled by linear scanning control of the pulse repetition rate on the source site, while diverse forms of unequal-path, non-symmetric measurements are taken with nanometer precision for different targets simply by delivering fr-scanned pulses through a fiber network. This proposed scheme has no restriction on the number of interferometer sites being integrated concurrently, allowing more diverse industrial applications of ultrashort lasers despite increased system cost and complexity.
关键词： Surface profiling,Low coherence scanning interferometry,Repetition rate scanning,Multiple targets,Femtosecond laser
更新于2025-09-12 10:27:22
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Proton acceleration due to laser plasma interactions from mass-limited spherical targets
摘要： The proton acceleration processes involved in the interaction of an ultrashort circularly polarized laser with a near-critical density spherical target are investigated in this paper using three dimensional particles in cell simulations. Both the target size and the target density are varied to understand their influence on the accelerated beam of protons. The target is efficiently heated by relativistic transparency, and a complicated interplay is observed between the participating interaction processes. The electron heating and recirculations help in the formation of shocks which exert a further push to the protons accelerated by the electrostatic sheath formed due to the ponderomotive force. A maximum peak proton energy of about 40 MeV is observed, which is the result of the cumulative effects of various acceleration mechanisms. Electron jets are observed in the forward laser direction for the larger target size, which suppresses the energy of the proton beams.
关键词： spherical targets,laser plasma interactions,electrostatic sheath,electron heating,proton acceleration,relativistic transparency,ponderomotive force,shock formation
更新于2025-09-12 10:27:22
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AIP Conference Proceedings [AIP Publishing PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON ADVANCES AND APPLICATIONS IN PLASMA PHYSICS (AAPP 2019) - St. Petersburg, Russia (18–20 September 2019)] PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON ADVANCES AND APPLICATIONS IN PLASMA PHYSICS (AAPP 2019) - Controlling the energy distribution of accelerated particles by choosing the relief parameters of the target irradiated by a short laser pulse of relativistic intensity
摘要： Secondary emission from laser produced plasma is governed by the electron distribution function. Therefore, its control is of utmost importance to steer the emission e.g. of ultra-short bursts of high energy photons and ions for decisive application. In our theoretical analysis including comparison to recent experiments we follow this route and study how the energy is transferred from short laser pulse to the energy of fast ions and X-rays. We make use of ion and Kα emission which respond differently to branches of the electron distribution function when we optimize the laser light absorption via structuring of the target surface. Our investigation comprises laser intensities up to 5x1020 W/cm2 produced with femtosecond near infrared laser pulses and Titanium foil targets of a few micrometer thicknesses. In particular, we reveal an energy relaxation process of hot electrons, which determines the observed laser intensity dependence of secondary emission and points to the benefit of target surface structuring in different optimization scenarios.
关键词： structured targets,Laser–plasma interaction
更新于2025-09-12 10:27:22