基于状态连续变化的Hopfield神经网络的图像复原

针对图像复原提出了神经元状态连续变化的Hopfield神经网络模型,详细讨论了两种连续函数串行、全并 行复原算法的收敛性和参数选择,仿真实验表明,该模型能够精确达到能量极小点,并对复原图像的信噪比有一定的提高。     

POLSAR Image Analysis of Wetlands Using a Modified Four-Component Scattering Power Decomposition

It is important to monitor environmental changes of the Earth's cover by remotely sensed data. This paper analyzes seasonal changes of a wetland by a modified polarimetric four-component scattering power decomposition method. The data sets analyzed here are L- and X-band fully polarimetric synthetic aperture radar (POLSAR) data, which have been acquired by the NICT/JAXA airborne polarimetric and interferometric synthetic aperture radar system in 2004. Since there existed a deficiency in the currently adopted decomposition schemes in that negative powers appear in a few pixels in the image analysis, we modified the approach taking into account physical conditions. It is shown by the modified scheme that the seasonal changes and features of the vegetation near Sakata Lagoon in Niigata, Japan, are observed clearly, demonstrating the utility of POLSAR image analysis for wetland assessments in general.     

Determination of the Complex Permittivity of Materials by a Modified Resonator Method Based on the Theory of Small Perturbations Using a Resonator of the Reflective Type

Journal of Communications Technology and Electronics - A modified resonator method for determining the complex permittivity of materials based on the theory of small perturbations where a resonator...     

Formation of Low-Resistance Ohmic Contact by Damage-Proof Selective-Area Growth of Single-Crystal <Emphasis Type="Italic">n</Emphasis><Superscript>+</Superscript>-GaN Using Plasma-Assisted Molecular Beam Epitaxy

To achieve very low ohmic contact resistance, an n ⁺-GaN layer was selectively deposited using plasma-assisted molecular beam epitaxy (PAMBE). During this process polycrystalline GaN grew on the patterned SiO₂ region, which was subsequently removed by a heated KOH solution, resulting in damage to the n ⁺-GaN surface. To prevent this damage, an additional SiO₂ layer was selectively deposited only on the n ⁺-GaN region. To optimize the fabrication process the KOH etching time and n ⁺-GaN layer thickness were adjusted. This damage-proof scheme resulted in a specific contact resistance of 4.6 × 10⁻⁷ Ω cm². In comparison, the resistance with the KOH etching damage was 4.9 × 10⁻⁶ Ω cm² to 24 × 10⁻⁶ Ω cm². The KOH etching produced a large number of pits (4.1 × 10⁸ cm⁻²) and degraded the current transport. X-ray photoelectron spectroscopy (XPS) and secondary-ion mass spectrometry (SIMS) analysis indicated that KOH etching was very effective in removing the oxide from the GaN surface and that the O-H bonding at the GaN surface was likely responsible for the degraded contact performance. The optimum n ⁺-GaN thickness was found to be 54 nm.