- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Quantum image edge extraction based on Laplacian operator and zero-cross method
摘要： Edge detection, as a fundamental problem in image processing and computer vision, is an indispensable task in digital image processing. Because of the sharp increase in the image data in the actual applications, real-time problem has become a limitation in classical image processing. In this paper, based on the novel enhanced quantum image representation (NEQR) of digital images, an enhanced quantum edge detection algorithm is investigated, which combines the classical Laplacian operator and zero-cross method. Because NEQR utilizes the superposition state of qubit sequence to store all the pixels of an image, the corresponding quantum image edge detection algorithm can realize parallel computation to implement the Laplacian ?lter and further calculate the image intensity of all the pixels according zero-cross method. The circuit complexity analysis demonstrates that our presented quantum image edge algorithm can reach a signi?cant and exponential speedup compared to classical counterparts. Hence, our proposed quantum image edge detection algorithm would resolve the real-time problem of image edge extraction in practice image processing.
关键词： Zero-cross method,Edge detection,Quantum image processing,Laplacian operator
更新于2025-09-04 15:30:14
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Extracting Displacement and Strain Fields from Checkerboard Images with the Localized Spectrum Analysis
摘要： The performance of white-light full-field measurement methods strongly depends on the nature of the pattern used to mark the surface on which displacements and strains are measured. Finding optimized patterns is therefore a topical question. The aim of this study is to examine the case of the checkerboard pattern. It is first shown that this periodic pattern can be processed with a Fourier-based technique such as LSA. Experiments are then carried out to compare the noise level in displacement and strain maps obtained by processing classic 2D grid and checkerboard images. The conclusion is that the noise level observed in displacement and strain maps is significantly lower with a checkerboard than with a classic 2D grid. A notched specimen is finally tested to illustrate that very low strain levels can be measured with checkerboard patterns.
关键词： Grid method,Checkerboard,Localized spectrum analysis,Optimal pattern,Digital image correlation,Heteroscedastic noise,Metrology,Pattern optimization,Windowed Fourier transform
更新于2025-09-04 15:30:14
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Magnetism of Eu-doped GaN modulations by spinodal nanodecomposition
摘要： By the Monte Carlo method, magnetic properties have been investigated for Eu-doped GaN involving internal nanostructures induced by nanoscale spinodal decomposition, where these nanostructures are spontaneously or artificially formed. In the present simulations, hysteretic and nonhysteretic magnetization curves are observed in the systems with the large-sized and small-sized nanostructures, respectively. These nanostructures affect the blocking temperatures as well. Furthermore, they influence temperature-dependent energy barriers of spin flipping; therefore, the simulations suggest that the magnetization is thermally stable. However, we observe that the blocking temperatures are smaller than the experimental values, which may be due to atomic vacancies.
关键词： magnetic properties,blocking temperatures,Eu-doped GaN,Monte Carlo method,spinodal decomposition
更新于2025-09-04 15:30:14
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[IEEE 2018 IEEE International Conference on Electrical Engineering and Photonics (EExPolytech) - Saint Petersburg, Russia (2018.10.22-2018.10.23)] 2018 IEEE International Conference on Electrical Engineering and Photonics (EExPolytech) - Methods and Algorithms for Numerical Calculations in Dynamic Light Scattering Problems
摘要： The paper is concerned with the problem of the ill-conditioned task in dynamic light scattering. We briefly review general inverse methods for particle sizing via dynamic light scattering and select the most promising ones. We suggest algorithms for numerical calculations based on variation methods and demonstrate the possibilities of Tikhonov regularization algorithm by using model experiments. The accuracy of the algorithm proves to be in good agreement with the demands of biomedical experiments.
关键词： Tikhonov method,regularization,numerical calculations,dynamic light scattering,sizing
更新于2025-09-04 15:30:14
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Three Cadmium Tartratoborates with Good Second Harmonic Generation (SHG) or Luminescence Performances
摘要： Three new cadmium(II) tartratoborates, namely, Cd5[(C4H2O6)2B]2(H2O)8·3H2O (1), K2Cd4[(C4H2O6)2B]2(H2O)2 (2), and Li0.92K1.08Cd1.5[(C4H2O6)2B](H2O)2 (3), have been successfully synthesized by the hydrothermal method. Compounds 1?3 belong to centric C2/c, acentric Pc, and the polar C2, respectively. Through based on the same hybrid borate?tartrate [(C4H2O6)2B]5? anions, they exhibit different structures. The [(C4H2O6)2B]5? anion is composed of two tartrate anions and a B(OH)4? unit. Compound 1 features a novel 2D {Cd3[(C4H2O6)2B]2(H2O)2}4? anionic layers and [Cd2O10] dimers, forming tunnels of large 14-MRs which are filled by the non-coordination water molecules. Compound 2 has a characteristic 3D network based on {Cd2[(C4H2O6)2B]}? units interlinked via carboxylate groups, forming tunnels of 11-MRs, half of which stuffed with the K+ ions. Compound 3 features 2D {Cd4[(C4H2O6)4B]}3+ layers which are separated by K/Li ions. Luminescent studies suggest that they emit blue light. Compounds 2 and 3 display phase-matchable second harmonic generation signs of about 3.2× and 1.5× KH2PO4, respectively.
关键词： luminescence,hydrothermal method,cadmium tartratoborates,second harmonic generation
更新于2025-09-04 15:30:14
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Catalyst-Assisted Solution–Liquid–Solid Synthesis of CdS/CuInSe <sub/>2</sub> and CuInTe <sub/>2</sub> /CuInSe <sub/>2</sub> Nanorod Heterostructures
摘要： Axial nanowire heterostructures composed of cadmium sulfide (CdS)/copper indium diselenide (CuInSe2) and copper indium telluride (CuInTe2)/copper indium diselenide (CuInSe2) were synthesized by a solution?liquid?solid (SLS) method with the catalyzer of bismuth nanocrystals. Electron microscopy and diffraction studies show CuInTe2 and CuInSe2 segments growing along the [112] direction with a clear epitaxial interface between them. In CdS/CuInSe2 nanorod heterostructures, CuInSe2 and CdS segments grow along the [112] and [111] direction, respectively, with an obvious epitaxial interface between them. Energy-dispersive X-ray spectrometry demonstrates the alloy-free composition modulation in two nanorod heterostructures. In CuInTe2/CuInSe2 nanorod heterostructures, Te and Se are localized in CuInTe2 and CuInSe2 segments, respectively. Cu/In/Se and Cd/S are localized in the CuInSe2 and CdS sections of the CdS/CuInSe2 nanorod heterostructures. This research confirms that the SLS mechanism provides a general alternate technique to prepare multicomponent axial 1D heterostructures that have been difficult to generate by using either catalyst-free solution-phase synthesis or vapor?liquid?solid growth.
关键词： epitaxial interface,nanowire heterostructures,solution?liquid?solid (SLS) method,bismuth nanocrystals,energy-dispersive X-ray spectrometry
更新于2025-09-04 15:30:14
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Silicon Film Deposition Using a Gas-Jet Plasma-Chemical Method: Experiment and Gas-Dynamic Simulation
摘要： This paper presents the results of an experimental study, numerical calculation, and analysis within the framework of a gas-dynamic model of silicon ?lm deposition by a gas-jet plasma-chemical method. A numerical model of gas mixtures ?owing out of an annular nozzle unit and into a reactor is developed, and it allows one to determine a ?lm thickness distribution over the surface of substrates placed in the reactor and satisfactorily describes the experimental data obtained.
关键词： reactor,simulation,plasma-chemical deposition,thin silicon ?lms,free jet,electron-beam plasma,DSMC method
更新于2025-09-04 15:30:14
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Tunneling ionization of atoms and ions in a linear electromagnetic wave and a constant magnetic field and the “imaginary time” method
摘要： The tunneling ionization of atoms and negative ions in an intense linearly polarized laser ?eld and a constant uniform magnetic ?eld is discussed in the quasiclassical theory framework. We use the “imaginary time” method, where tunneling is described by the classical equations of motion but with purely imaginary “time” to derive the extremal subbarrier trajectory of the photoelectron. This allows to obtain simple analytical expressions for ionization rates in the tunneling regime for an arbitrary angle between a laser beam and a constant magnetic ?eld accounting for the Coulomb interaction of the photoelectron with the atomic core. The resonance case, when the frequency of a monochromatic electromagnetic wave and the cyclotron frequency are equal, is also considered. The limits of weak and strong magnetic ?elds and the expressions for the barrier width and the emission angle of photoelectrons are discussed. It is shown that a magnetic ?eld in the presence of a linear electromagnetic wave increases the barrier width and thus decreases the ionization probability, i.e., stabilizes the bound level.
关键词： linear electromagnetic wave,imaginary time method,atoms,ions,quasiclassical theory,tunneling ionization,constant magnetic field
更新于2025-09-04 15:30:14
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Asymmetric light transmission effect based on an evolutionary optimized semi-Dirac cone dispersion photonic structure
摘要： In this paper, we present the numerical and experimental demonstration of asymmetric light transmission by a compact photonic crystal (PC) structure, which sustains semi-Dirac cone dispersion. The semi-Dirac point is obtained by exploiting plane-wave expansion method in a rectangular unit cell of a cylindrical dielectric rod, forming a PC structure. The preselected part of the corresponding PC structure is optimized via differential evolution to maximize the transmission efficiency in one direction, and to minimize in the opposite direction. In this regard, finite-difference time-domain method is integrated with the optimization algorithm to numerically design a compact PC structure with asymmetric light transmission effect. The detailed numerical investigation of the optimized PC structure is represented, and the experiments in the microwave regime are performed to verify the numerical results. The experimentally measured transmission efficiency reaches 78% for one direction, whereas in the opposite direction it reduces to 11%. The physical mechanism of asymmetric light transmission is related to differences of the projection of the wave incident from both directions into the eigenmodes of the photonic structure.
关键词： asymmetric light transmission,semi-Dirac cone dispersion,photonic crystal,differential evolution,finite-difference time-domain method
更新于2025-09-04 15:30:14
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[IEEE 2018 XIV International Scientific-Technical Conference on Actual Problems of Electronics Instrument Engineering (APEIE) - Novosibirsk, Russia (2018.10.2-2018.10.6)] 2018 XIV International Scientific-Technical Conference on Actual Problems of Electronics Instrument Engineering (APEIE) - Virtual Instrument for Assessment of Simulated Signal Integrated Harmonics Factors
摘要： The block diagram of the LabVIEW virtual instrument for the assessment of simulated signal integrated harmonics factors is presented. This virtual device version is equipped with the input module for waveform data points import file. The examples of measurement and use of the integrated harmonics factors values of the investigated voltage for estimating the harmonic distortion of the load circuit current are shown.
关键词： method of the differential equations algebraization (ADE),Weighted THD,n-order integrated voltage (current) harmonics factor (IHF),LabVIEW virtual instrument,PSIM
更新于2025-09-04 15:30:14