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关键词： Paddy rice   sample generation   multimodal   feature fusion  

摘要： Accurate information on rice planting areas and spatial distribution is critical for agricultural management in China;however, mapping efforts in regions like Sichuan Province are severely constrained by persistent cloud cover and fragmented terrain. Existing phenology-based methods and coarse-resolution products often fail to provide precise paddy localizations or usable training labels in such complex environments. To address these limitations, this study proposes a robust framework integrating optical and Synthetic Aperture Radar (SAR) imagery. The methodology employs a phenology-driven strategy for rapid candidate area annotation, coupled with an asymmetric feature extraction mechanism that incorporates a Multi-Scale Semantic Enhancement Module (MSEM) and a Category-Balanced Feature Fusion Module (CBFM) to facilitate adaptive and effective cross-modal fusion. Applying this framework to the Tianfu New Area (2019-2023) yielded 10-meter resolution rice distribution maps with a rice Intersection over Union (IoU) of 83.31% and a statistical correlation (R-2) of 0.972. These results demonstrate the framework's capacity for selective multi-source fusion and cost-effective sampling, facilitating precise rice mapping in challenging agricultural landscapes.

关键词： Cd1-xMnxS   Chemical bath deposition   Semiconductor   TFSC   Thin film  

摘要： In this study, Cd_1-xMn_xS ($\mathrm{x}=0.4$) thin films were synthesized using a cost-effective chemical bath deposition technique. The influence of cobalt doping at various concentrations (1%, 2%, 3%, and 4% v/v) on the structural, morphological, optical, and electrical properties of the films was systematically investigated. XRD analysis confirmed the polycrystalline cubic zinc blende structure of the thin films, with the (111) plane appearing as the most prominent diffraction peak. The crystallite size and crystallinity were found to increase with Co doping, while the microstrain and dislocation density decreased correspondingly. HRTEM images further revealed the lattice planes and corresponding interplanar spacings of the crystalline structure. FESEM analysis revealed that the deposited films were uniform, crack-free, and composed of nearly spherical grains, with the grain size increasing as the cobalt concentration increased. UV-Vis spectrophotometer analysis showed that all the thin films exhibited high transmittance (∼80 - 90%) in the visible and NIR regions. The band gap energy varies from ∼2.914 ± 0.001 to 2.875 ± 0.002 eV as the doping concentration changes. Electrical measurements confirmed the semiconducting and photoconducting behaviour of the thin films, with conductivity progressively increasing with dopant concentration, as evidenced by I–V characteristics recorded under both dark and illuminated conditions. These findings offer valuable insights into the suitability of cobalt-doped Cd_1-xMn_xS thin films as semiconducting materials for advanced optoelectronic applications, particularly for their potential implementation as window-layer components in thin-film photovoltaic devices.

关键词： Eigenvalue multiplicity   Laplacian eigenvalues   Line graphs   Trees   Unicyclic graphs  

摘要： Let G be a graph with $p(G)$ pendant vertices and $q(G)$ quasi-pendant vertices. Denote by $m_{L(G)}(\lambda )$ the multiplicity of λ as a Laplacian eigenvalue of G. Let $\bar{G}$ be the reduced graph of G, which can be obtained from G by deleting some pendant vertices such that $p(\bar{G})=q(\bar{G})$. We first prove that