Nondestructive testing of fiber array with multiple missing fibers

National audienceOur goal is to detect defects in composite materialscomposed by multilayer planar plates with a periodicset of circular cylindrical fibers embedded in each layer. As astarter, the work presented is electromagnetic (EM) modelingand imaging of missing fibers within a fiber array standingin air. The multiple scattering method is utilized to analyzethe electromagnetic behavior, and the corresponding imagingmodel is established directly from Lippman-Schwinger integralformulation. Standard MUltiple SIgnal Classification (MUSIC)and the proposed joint sparsity which borrows the idea ofsparse theory are applied to retrieve the locations of missingfibers. Numerical results are provided to confirm availabilityand accuracy of EM modeling and defect imaging

Association between genetically predicted rheumatoid arthritis and alopecia areata: a two-sample Mendelian randomization study

BackgroundAlthough numerous observational studies have indicated a potential association between autoimmune diseases, such as rheumatoid arthritis (RA) and alopecia areata (AA), the research reports lack a clear causal relationship. In this study, our objective is to utilize the Mendelian randomization (MR) design to examine the potential causal association between RA and AA.MethodsTo investigate the causal relationship between RA and AA, we utilized large-scale gene aggregation data from genome-wide association studies (GWAS), including RA (n=58,284) and AA (n=361,822) based on previous observational studies. In our analysis, we mainly employed the inverse variance-weighted (IVW) method of the random effects model, supplemented by the weighted median (WM) method and the MR Egger method.ResultsThe findings from the IVW methods revealed a significant association between genetically predicted RA and an increased likelihood of AA, as evidenced by an odds ratio of 1.21 (95%CI = 1.11-1.32; P < 0.001. Both the WM method and MR-Egger regression consistently showed significant directional outcomes (Both P < 0.05), indicating a robust association between RA and AA. Additionally, both the funnel plot and the MR-Egger intercepts provided evidence of the absence of directional pleiotropy, suggesting that the observed association is not influenced by other common genetic factors.ConclusionsThe results of the study suggest a possible link between genetically predicted RA and AA. This finding highlights the importance for individuals diagnosed with RA to remain vigilant and aware of the potential development of AA. Regular monitoring and early detection can be crucial in managing and addressing this potential complication

GPT-4V in Wonderland: Large Multimodal Models for Zero-Shot Smartphone GUI Navigation

We present MM-Navigator, a GPT-4V-based agent for the smartphone graphical user interface (GUI) navigation task. MM-Navigator can interact with a smartphone screen as human users, and determine subsequent actions to fulfill given instructions. Our findings demonstrate that large multimodal models (LMMs), specifically GPT-4V, excel in zero-shot GUI navigation through its advanced screen interpretation, action reasoning, and precise action localization capabilities. We first benchmark MM-Navigator on our collected iOS screen dataset. According to human assessments, the system exhibited a 91\% accuracy rate in generating reasonable action descriptions and a 75\% accuracy rate in executing the correct actions for single-step instructions on iOS. Additionally, we evaluate the model on a subset of an Android screen navigation dataset, where the model outperforms previous GUI navigators in a zero-shot fashion. Our benchmark and detailed analyses aim to lay a robust groundwork for future research into the GUI navigation task. The project page is at https://github.com/zzxslp/MM-Navigator.Comment: Work in progres

Design and test of a new pre-drilling in-situ rock mass shear instrument

Based on the arched structure and the characteristics of the wedge-shaped cutter intruding into the rock mass, a new pre-drilling in-situ rock mass shearing instrument suitable for in-situ rock mass shear strength measurement has been developed. By designing the overall structure of the pre-drilling in-situ rock mass shear instrument, and using finite element analysis software to simulate and analyze the key components, the simulation results show that the design of the key components is reasonable; in addition, the shear instrument is calibrated and tested. The field test was carried out on the poured concrete platform, and the test showed that the performance parameters met the design requirements and had good in-situ test performance

Electromagnetic imaging of damages in fibered layered laminates via equivalence theory

International audienceAbstract—Electromagnetic non-destructive testing of damaged multi-layer fiber-reinforced laminates is of concern. Each layer involves periodically positioned circular cylindrical fibers embedded within a matrix medium. Missing, displaced, shrunk, expanded fibers as well as circular inclusions inside a fiber are modeled as properly designed equivalent sources inside the undamaged structure. Then, the location of damages is retrieved via simply searching for such equivalent sources. A sparsity-constrained solution as well as classical algorithms including truncated singular value decomposition (TSVD), multiple signal classification (MUSIC) and basic matching pursuit (BMP) are considered, and their pros and cons are illustrated by numerical results in various configurations

Electromagnetically locating damages in layered fiber-reinforced periodic laminates with a joint- sparsity-based method

International audienc