134 research outputs found

    Volterra type integration operators from Bergman spaces to Hardy spaces

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    We completely characterize the boundedness of the Volterra type integration operators JbJ_b acting from the weighted Bergman spaces AαpA^p_\alpha to the Hardy spaces HqH^q of the unit ball of Cn\mathbb{C}^n for all 0<p,q<∞0<p,q<\infty. A partial solution to the case n=1n=1 was previously obtained by Z. Wu in \cite{Wu}. We solve the cases left open there and extend all the results to the setting of arbitrary complex dimension nn. Our tools involve area methods from harmonic analysis, Carleson measures and Kahane-Khinchine type inequalities, factorization tricks for tent spaces of sequences, as well as techniques and integral estimates related to Hardy and Bergman spaces.Comment: 26 pages, 1 figur

    LDCA: Local Descriptors with Contextual Augmentation for Few-Shot Learning

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    Few-shot image classification has emerged as a key challenge in the field of computer vision, highlighting the capability to rapidly adapt to new tasks with minimal labeled data. Existing methods predominantly rely on image-level features or local descriptors, often overlooking the holistic context surrounding these descriptors. In this work, we introduce a novel approach termed "Local Descriptor with Contextual Augmentation (LDCA)". Specifically, this method bridges the gap between local and global understanding uniquely by leveraging an adaptive global contextual enhancement module. This module incorporates a visual transformer, endowing local descriptors with contextual awareness capabilities, ranging from broad global perspectives to intricate surrounding nuances. By doing so, LDCA transcends traditional descriptor-based approaches, ensuring each local feature is interpreted within its larger visual narrative. Extensive experiments underscore the efficacy of our method, showing a maximal absolute improvement of 20\% over the next-best on fine-grained classification datasets, thus demonstrating significant advancements in few-shot classification tasks

    Composition Operators from Certain μ

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    Some necessary and sufficient conditions are established for composition operators Cφ to be bounded or compact from μ-Bloch type spaces Bμ to Qp spaces. Moreover, the boundedness, compactness, and Fredholmness of composition operators on little spaces Qp,0 are also characterized

    Researches on Key Algorithms in Analogue Seismogram Records Vectorization

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    Abstract: History paper seismograms are very important information for earthquake monitoring and prediction, and the vectorization of paper seismograms is a very import problem to be resolved. In our study, a new tracing algorithm for simulated seismogram curves based on visual filed feature is presented. We also give out the technological process to vectorizing simulated seismograms, and an analog seismic record vectorization system has been accomplished independently. Using it, we can precisely and speedy vectorize analog seismic records (need professionals to participate interactively)

    Genomic analyses provide insights into the genome evolution and environmental adaptation of the tobacco moth Ephestia elutella

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    Ephestia elutella is a major pest responsible for significant damage to stored tobacco over many years. Here, we conduct a comparative genomic analysis on this pest, aiming to explore the genetic bases of environmental adaptation of this species. We find gene families associated with nutrient metabolism, detoxification, antioxidant defense and gustatory receptors are expanded in the E. elutella genome. Detailed phylogenetic analysis of P450 genes further reveals obvious duplications in the CYP3 clan in E. elutella compared to the closely related species, the Indianmeal moth Plodia interpunctella. We also identify 229 rapidly evolving genes and 207 positively selected genes in E. elutella, respectively, and highlight two positively selected heat shock protein 40 (Hsp40) genes. In addition, we find a number of species-specific genes related to diverse biological processes, such as mitochondria biology and development. These findings advance our understanding of the mechanisms underlying processes of environmental adaptation on E. elutella and will enable the development of novel pest management strategies
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