33 research outputs found

    A remark on the Castelnuovo-Mumford regularity of powers of ideal sheaves

    Full text link
    We show that a bound of the Castelnuovo-Mumford regularity of any power of the ideal sheaf of a smooth projective complex variety X⊆PrX\subseteq\mathbb{P}^r is sharp exactly for complete intersections, provided the variety XX is cut out scheme-theoretically by several hypersurfaces in Pr\mathbb{P}^r. This generalizes a result of Bertram-Ein-Lazarsfeld.Comment: 7 pages, to appear in the Journal of Pure and Applied Algebr

    Well-posedness of stochastic partial differential equations with fully local monotone coefficients

    Full text link
    Consider stochastic partial differential equations (SPDEs) with fully local monotone coefficients in a Gelfand triple V⊆H⊆V∗V\subseteq H \subseteq V^*: \begin{align*} \left\{ \begin{aligned} dX(t) & = A(t,X(t))dt + B(t,X(t))dW(t), \quad t\in (0,T], \\ X(0) & = x\in H, \end{aligned} \right. \end{align*} where \begin{align*} A: [0,T]\times V \rightarrow V^* , \quad B: [0,T]\times V \rightarrow L_2(U,H) \end{align*} are measurable maps, L2(U,H)L_2(U,H) is the space of Hilbert-Schmidt operators from UU to HH and WW is a UU-cylindrical Wiener process. Such SPDEs include many interesting models in applied fields like fluid dynamics etc. In this paper, we establish the well-posedness of the above SPDEs under fully local monotonicity condition solving a longstanding open problem. The conditions on the diffusion coefficient B(t,⋅)B(t,\cdot) are allowed to depend on both the HH-norm and VV-norm. In the case of classical SPDEs, this means that B(⋅,⋅)B(\cdot,\cdot) could also depend on the gradient of the solution. The well-posedness is obtained through a combination of pseudo-monotonicity techniques and compactness arguments.Comment: 45 page

    Hard Lefschetz theorems for free line bundles

    Full text link
    We introduce a partial positivity notion for algebraic maps via the defect of semismallness. This positivity notion is modeled on mm-positivity in the analytic setting and mm-ampleness in the geometric setting. Using this positivity condition for algebraic maps, we establish K\"ahler packages, that is, Hard Lefschetz theorems and Hodge-Riemann bilinear relations, for the complete intersections of Chern classes of free line bundles.Comment: 14 pages; comments welcome

    ChatRadio-Valuer: A Chat Large Language Model for Generalizable Radiology Report Generation Based on Multi-institution and Multi-system Data

    Full text link
    Radiology report generation, as a key step in medical image analysis, is critical to the quantitative analysis of clinically informed decision-making levels. However, complex and diverse radiology reports with cross-source heterogeneity pose a huge generalizability challenge to the current methods under massive data volume, mainly because the style and normativity of radiology reports are obviously distinctive among institutions, body regions inspected and radiologists. Recently, the advent of large language models (LLM) offers great potential for recognizing signs of health conditions. To resolve the above problem, we collaborate with the Second Xiangya Hospital in China and propose ChatRadio-Valuer based on the LLM, a tailored model for automatic radiology report generation that learns generalizable representations and provides a basis pattern for model adaptation in sophisticated analysts' cases. Specifically, ChatRadio-Valuer is trained based on the radiology reports from a single institution by means of supervised fine-tuning, and then adapted to disease diagnosis tasks for human multi-system evaluation (i.e., chest, abdomen, muscle-skeleton, head, and maxillofacial &\& neck) from six different institutions in clinical-level events. The clinical dataset utilized in this study encompasses a remarkable total of \textbf{332,673} observations. From the comprehensive results on engineering indicators, clinical efficacy and deployment cost metrics, it can be shown that ChatRadio-Valuer consistently outperforms state-of-the-art models, especially ChatGPT (GPT-3.5-Turbo) and GPT-4 et al., in terms of the diseases diagnosis from radiology reports. ChatRadio-Valuer provides an effective avenue to boost model generalization performance and alleviate the annotation workload of experts to enable the promotion of clinical AI applications in radiology reports
    corecore