SearcharxivSearch

arXiv subjects

Wang Lei

Publications and source records attributed to Wang Lei.

6 recordsLinked to original sources

Transfer Learning Strategies for Pathological Foundation Models: A Systematic Evaluation in Brain Tumor Classification

Foundation models pretrained on large-scale pathology datasets have shown promising results across various diagnostic tasks. Here, we present a systematic evaluation of transfer learning strategies for brain tumor classification using these models. We analyzed 254 cases comprising five major tumor types: glioblastoma, astrocytoma, oligodendroglioma, primary central nervous system lymphoma, and metastatic tumors. Comparing state-of-the-art foundation models with conventional approaches, we found that foundation models demonstrated robust classification performance with as few as 10 patches per case, despite the traditional assumption that extensive per-case image sampling is necessary. Furthermore, our evaluation revealed that simple transfer learning strategies like linear probing were sufficient, while fine-tuning often degraded model performance. These findings suggest a paradigm shift from "training encoders on extensive pathological data" to "querying pre-trained encoders with labeled datasets", providing practical implications for implementing AI-assisted diagnosis in clinical pathology.

eess.IV

Physical and Structural Design of Fast Extraction Kickers for CSNS/RCS

China Spallation Neutron Source (CSNS) is a high intensity beam facility being built now in China. Three kicker assemblies, eight pulsed magnets, will be used in the CSNS rapid circle synchrotron (RCS). The physical and structural designs of eight kicker magnets that are grouped in 5 different types are presented. The results of OPERA-3D simulation show that magnet center field integral meet the physics requirements of design by choosing a suitable magnet coil structure. Field uniformity for 60% width is +/-0.7%. The ferrite magnet structure and composition is introduced, and the high voltage feedthrough design, the installation of six magnets in long vacuum cavity design is discussed.

physics.acc-ph

Network Coding for Energy-Efficient Distributed Storage System in Wireless Sensor Networks

A network coding-based scheme is proposed to improve the energy efficiency of distributed storage systems in WSNs (wireless sensor networks), which mainly focuses on two problems: firstly, consideration is given to effective distributed storage technology in WSNs; secondly, we address how to repair the data in failed storage nodes with less resource. For the first problem, we propose a method to obtain a sparse generator matrix to construct network codes, and this sparse generator matrix is proven to be the sparsest. Benefiting from the sparse generator matrix, the energy consumption required to implement distributed storage is reduced. For the second problem, we designed a network coding-based iterative repair method, which adequately utilizes the idea of re-encoding at intermediate nodes from network coding theory. Benefiting from the re-encoding, the energy consumption required by data repair is significantly reduced. Moreover, we provide an explicit lower bound of field size required by this scheme, which implies that this scheme can work over a very small field and the required computation overhead of coding is very low. The simulation result verifies that by using our scheme, the total energy consumption required to implement distributed storage system in WSNs can be reduced on the one hand, and on the other hand, this method can also balance energy consumption of the networks.

cs.NI

Full one-loop supersymmetric corrections to charged Higgs boson pair production in $γγ$ collisions

The complete one-loop electroweak corrections to charged Higgs boson pair production in $γγ$ collision mode at linear colliders in the minimal supersymmetric standard model (MSSM), are calculated in this paper. We discuss the dependence of the corrections to the subprocess $γγ\to H^{+}H^{-}$ on the related parameters, such as the colliding energy, charged Higgs boson mass $M_{H^{\pm}}$ and some supersymmetric parameters $\tan β$, $M_{SUSY}$ and gaugino mass parameter $M_2$. We find that the corrections generally reduce the Born cross sections and the relative one-loop corrections to both the subprocess typically in the range of -10% to -30%. We also present the numerical results at the SPS1a' point from the SPA project. We conclude that the full one-loop electroweak corrections to subprocess $γγ\to H^{+}H^{-}$ and the parent process $e^+e^- \to γγ\to H^{+}H^{-}$ are significant and therefore should be considered in precise analysis of charged Higgs boson pair productions via $γγ$ collision at future linear colliders.

hep-ph

R-parity violation effect on the top-quark pair production at linear colliders

We investigate in detail the effects of the R-parity lepton number violation in the minimal supersymmetric standard model (MSSM) on the top-quark pair production via both $e^--e^+$ and $γ-γ$ collision modes at the linear colliders. We find that with the present experimental constrained $\rlap/{R}$ parameters, the effect from $\rlap/{R}$ interactions on the processes $e^+e^-\to t\bar{t}$ and $e^+e^- \to γγ\to t\bar{t}$ could be significant and may reach -30% and several percent, respectively. Our results show that the $\rlap/{R}$ effects are sensitive to the c.m.s. energy and the relevant $\rlap/{R}$ parameters. However, they are not sensitive to squark and slepton masses when $m_{\tilde{q}} \geq 400 GeV$ (or $m_{\tilde{l}} \geq 300 GeV$) and are almost independent on the $\tanβ$

hep-ph

Higgs-Boson Production Associated with a Single Bottom Quark in Supersymmetric QCD

Due to the enhancement of the couplings between Higgs boson and bottom quarks in the minimal sypersymmetric standard model (MSSM), the cross section of the process pp(p\bar{p}) \to h^0b(h^0\bar{b})+X at hadron colliders can be considerably enhanced. We investigated the production of Higgs boson associated with a single high-p_T bottom quark via subprocess bg(\bar{b}g) \to h^0b(h^0\bar{b}) at hadron colliders including the next-to-leading order (NLO) QCD corrections in MSSM. We find that the NLO QCD correction in the MSSM reaches 50%-70% at the LHC and 60%-85% at the Fermilab Tevatron in our chosen parameter space.

hep-ph