409 research outputs found

    A Rapid Monitoring Method for Natural Gas Safety Monitoring

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    The quick leakage alarm and the accurate concentration prediction are two important aspects of natural gas safety monitoring.  In this paper, a rapid monitoring method of sensor data sharing, rapid leakage alarm and simultaneous output of concentrations prediction is proposed to accelerate the alarm speed and predict the possible impact of leakage.  In this method, the Dempster-Shafer evidence theory is used to fuse the trend judgment and the CUSUM (cumulative sum) and the Gauss-Newton iteration is used to predict the concentration.  The experiment system based on the TGS2611 natural gas sensor was built.  The results show that the fusion method is significantly better than the single monitoring method.  The alarm time of fusion method was more advanced than that of the CUSUM method and the trend method (being averagely, 10.4% and 7.6% in advance in the CUSUM method and the trend method respectively).  The relative deviations of the predicted concentration were the maximum (13.3%) at 2000 ppm (parts per million) and the minimum (0.8%) at 6000 ppm, respectively

    Prompt-Based Zero- and Few-Shot Node Classification: A Multimodal Approach

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    Multimodal data empowers machine learning models to better understand the world from various perspectives. In this work, we study the combination of \emph{text and graph} modalities, a challenging but understudied combination which is prevalent across multiple settings including citation networks, social media, and the web. We focus on the popular task of node classification using limited labels; in particular, under the zero- and few-shot scenarios. In contrast to the standard pipeline which feeds standard precomputed (e.g., bag-of-words) text features into a graph neural network, we propose \textbf{T}ext-\textbf{A}nd-\textbf{G}raph (TAG) learning, a more deeply multimodal approach that integrates the raw texts and graph topology into the model design, and can effectively learn from limited supervised signals without any meta-learning procedure. TAG is a two-stage model with (1) a prompt- and graph-based module which generates prior logits that can be directly used for zero-shot node classification, and (2) a trainable module that further calibrates these prior logits in a few-shot manner. Experiments on two node classification datasets show that TAG outperforms all the baselines by a large margin in both zero- and few-shot settings.Comment: Work in progres

    Polynomial based key predistribution scheme in wireless mesh networks

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    Wireless mesh networks (WMNs) have the ability to integrate with other networks while providing a fast and cost-saving deployment. The network security is one of important challenge problems in this kind of networks. This paper is focused on key management between mesh and sensor networks. We propose an efficient key pre-distribution scheme based on two polynomials in wireless mesh networks by employing the nature of heterogeneity. Our scheme realizes the property of bloom filters, i.e., neighbor nodes can discover their shared keys but have no knowledge on the different keys possessed by the other node, without the probability of false positive. The analysis presented in this paper shows that our scheme has the ability to establish three different security level keys and achieves the property of self adaptive security for sensor networks with acceptable computation and communication consumption

    In Art We Trust

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    Analysis of Bs→ϕννˉB_s\to\phi\nu\bar{\nu} at CEPC

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    The rare b→sννˉb\to s\nu\bar{\nu} decays are sensitive to contributions of new physics (NP) and helpful to resolve the puzzle of multiple BB flavor anomalies. In this work, we propose to study the b→sννˉb\to s\nu\bar{\nu} transition at a future lepton collider operating at the ZZ pole through the Bs→ϕννˉB_s \to \phi\nu\bar{\nu} decay. Using the Bs→ϕB_s\to\phi decay form factors from lattice simulations, we first update the SM prediction of BR(Bs→ϕννˉ)SM=(9.93±0.72)×10−6B_s \to \phi\nu\bar{\nu})_{\mathrm{SM}}=(9.93\pm 0.72)\times 10^{-6} and the corresponding ϕ\phi longitudinal polarization fraction FL,SM=0.53±0.04F_{L,{\mathrm{SM}}}=0.53\pm 0.04. Our analysis uses the full CEPC simulation samples with a net statistic of O(109)\mathcal{O}(10^9) ZZ decays. Precise ϕ\phi and BsB_s reconstructions are used to suppress backgrounds. The results show that BR(Bs→ϕννˉ)B_s \to \phi\nu\bar{\nu}) can be measured with a statistical uncertainty of O(%)\mathcal{O}(\%) and an S/BS/B ratio of O(1)\mathcal{O}(1) at the CEPC. The quality measures for the event reconstruction are also derived. By combining the measurement of BR(Bs→ϕννˉ)B_s \to \phi\nu\bar{\nu}) and FLF_L, the constraints on the effective theory couplings at low energy are given.Comment: 12 pages, 15 figures, 3 table
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