分析和区分网络协议流量的能力对于网络资源管理来说至关重要，以通过电信提供差异化​​服务。自动化协议分析（APA）至关重要，以显着提高效率，减少对人类专家的依赖。在APA中群集未知协议有许多自动化的无监督方法。但是，许多这样的方法没有使用不同的测试数据集充分探索。因此，未能展示泛化的鲁棒性。本研究提出了一种综合框架，以评估APA中的特征提取和聚类方法的各种组合。它还提出了一种自动选择数据集依赖模型参数的新颖方法，用于特征提取，从而提高性能。新颖的基于田间的象形化方法的有希望的结果也导致我们对APA中未知协议的特征提取和聚类的新型自动混合方法提出。我们所提出的混合方法在不同的测试数据集中的9个中的7个中最佳地进行了最佳，从而显示宽大，以概括不同的未知协议。它还优于所有测试数据集中的最先进的开源APA工具中的无监督聚类技术。

Graph neural networks (GNNs) have been shown to be highly sensitive to the choice of aggregation function. While summing over a node's neighbours can approximate any permutation-invariant function over discrete inputs, Cohen-Karlik et al. [2020] proved there are set-aggregation problems for which summing cannot generalise to unbounded inputs, proposing recurrent neural networks regularised towards permutation-invariance as a more expressive aggregator. We show that these results carry over to the graph domain: GNNs equipped with recurrent aggregators are competitive with state-of-the-art permutation-invariant aggregators, on both synthetic benchmarks and real-world problems. However, despite the benefits of recurrent aggregators, their $O(V)$ depth makes them both difficult to parallelise and harder to train on large graphs. Inspired by the observation that a well-behaved aggregator for a GNN is a commutative monoid over its latent space, we propose a framework for constructing learnable, commutative, associative binary operators. And with this, we construct an aggregator of $O(\log V)$ depth, yielding exponential improvements for both parallelism and dependency length while achieving performance competitive with recurrent aggregators. Based on our empirical observations, our proposed learnable commutative monoid (LCM) aggregator represents a favourable tradeoff between efficient and expressive aggregators.

This paper introduces the use of evolutionary algorithms for solving differential equations. The solution is obtained by optimizing a deep neural network whose loss function is defined by the residual terms from the differential equations. Recent studies have used stochastic gradient descent (SGD) variants to train these physics-informed neural networks (PINNs), but these methods can struggle to find accurate solutions due to optimization challenges. When solving differential equations, it is important to find the globally optimum parameters of the network, rather than just finding a solution that works well during training. SGD only searches along a single gradient direction, so it may not be the best approach for training PINNs with their accompanying complex optimization landscapes. In contrast, evolutionary algorithms perform a parallel exploration of different solutions in order to avoid getting stuck in local optima and can potentially find more accurate solutions. However, evolutionary algorithms can be slow, which can make them difficult to use in practice. To address this, we provide a set of five benchmark problems with associated performance metrics and baseline results to support the development of evolutionary algorithms for enhanced PINN training. As a baseline, we evaluate the performance and speed of using the widely adopted Covariance Matrix Adaptation Evolution Strategy (CMA-ES) for solving PINNs. We provide the loss and training time for CMA-ES run on TensorFlow, and CMA-ES and SGD run on JAX (with GPU acceleration) for the five benchmark problems. Our results show that JAX-accelerated evolutionary algorithms, particularly CMA-ES, can be a useful approach for solving differential equations. We hope that our work will support the exploration and development of alternative optimization algorithms for the complex task of optimizing PINNs.

Purpose: The aim of this study was to demonstrate the utility of unsupervised domain adaptation (UDA) in automated knee osteoarthritis (OA) phenotype classification using a small dataset (n=50). Materials and Methods: For this retrospective study, we collected 3,166 three-dimensional (3D) double-echo steady-state magnetic resonance (MR) images from the Osteoarthritis Initiative dataset and 50 3D turbo/fast spin-echo MR images from our institute (in 2020 and 2021) as the source and target datasets, respectively. For each patient, the degree of knee OA was initially graded according to the MRI Osteoarthritis Knee Score (MOAKS) before being converted to binary OA phenotype labels. The proposed UDA pipeline included (a) pre-processing, which involved automatic segmentation and region-of-interest cropping; (b) source classifier training, which involved pre-training phenotype classifiers on the source dataset; (c) target encoder adaptation, which involved unsupervised adaption of the source encoder to the target encoder and (d) target classifier validation, which involved statistical analysis of the target classification performance evaluated by the area under the receiver operating characteristic curve (AUROC), sensitivity, specificity and accuracy. Additionally, a classifier was trained without UDA for comparison. Results: The target classifier trained with UDA achieved improved AUROC, sensitivity, specificity and accuracy for both knee OA phenotypes compared with the classifier trained without UDA. Conclusion: The proposed UDA approach improves the performance of automated knee OA phenotype classification for small target datasets by utilising a large, high-quality source dataset for training. The results successfully demonstrated the advantages of the UDA approach in classification on small datasets.

Generalized Labeled Multi-Bernoulli (GLMB) densities arise in a host of multi-object system applications analogous to Gaussians in single-object filtering. However, computing the GLMB filtering density requires solving NP-hard problems. To alleviate this computational bottleneck, we develop a linear complexity Gibbs sampling framework for GLMB density computation. Specifically, we propose a tempered Gibbs sampler that exploits the structure of the GLMB filtering density to achieve an $\mathcal{O}(T(P+M))$ complexity, where $T$ is the number of iterations of the algorithm, $P$ and $M$ are the number hypothesized objects and measurements. This innovation enables an $\mathcal{O}(T(P+M+\log(T))+PM)$ complexity implementation of the GLMB filter. Convergence of the proposed Gibbs sampler is established and numerical studies are presented to validate the proposed GLMB filter implementation.

Principal Component Analysis (PCA) and its exponential family extensions have three components: observations, latents and parameters of a linear transformation. We consider a generalised setting where the canonical parameters of the exponential family are a nonlinear transformation of the latents. We show explicit relationships between particular neural network architectures and the corresponding statistical models. We find that deep equilibrium models -- a recently introduced class of implicit neural networks -- solve maximum a-posteriori (MAP) estimates for the latents and parameters of the transformation. Our analysis provides a systematic way to relate activation functions, dropout, and layer structure, to statistical assumptions about the observations, thus providing foundational principles for unsupervised DEQs. For hierarchical latents, individual neurons can be interpreted as nodes in a deep graphical model. Our DEQ feature maps are end-to-end differentiable, enabling fine-tuning for downstream tasks.

National Health and Nutritional Status Survey (NHANSS) is conducted annually by the Ministry of Health in Negara Brunei Darussalam to assess the population health and nutritional patterns and characteristics. The main aim of this study was to discover meaningful patterns (groups) from the obese sample of NHANSS data by applying data reduction and interpretation techniques. The mixed nature of the variables (qualitative and quantitative) in the data set added novelty to the study. Accordingly, the Categorical Principal Component (CATPCA) technique was chosen to interpret the meaningful results. The relationships between obesity and the lifestyle factors like demography, socioeconomic status, physical activity, dietary behavior, history of blood pressure, diabetes, etc., were determined based on the principal components generated by CATPCA. The results were validated with the help of the split method technique to counter verify the authenticity of the generated groups. Based on the analysis and results, two subgroups were found in the data set, and the salient features of these subgroups have been reported. These results can be proposed for the betterment of the healthcare industry.

基于近似基础的Koopman操作员或发电机的数据驱动的非线性动力系统模型已被证明是预测，功能学习，状态估计和控制的成功工具。众所周知，用于控制膜系统的Koopman发电机还对输入具有仿射依赖性，从而导致动力学的方便有限维双线性近似。然而，仍然存在两个主要障碍，限制了当前方法的范围，以逼近系统的koopman发电机。首先，现有方法的性能在很大程度上取决于要近似Koopman Generator的基础函数的选择；目前，目前尚无通用方法来为无法衡量保存的系统选择它们。其次，如果我们不观察到完整的状态，我们可能无法访问足够丰富的此类功能来描述动态。这是因为在有驱动时，通常使用时间延迟的可观察物的方法失败。为了解决这些问题，我们将Koopman Generator控制的可观察到的动力学写为双线性隐藏Markov模型，并使用预期最大化（EM）算法确定模型参数。 E-Step涉及标准的Kalman滤波器和更光滑，而M-Step类似于发电机的控制效果模式分解。我们在三个示例上证明了该方法的性能，包括恢复有限的Koopman-Invariant子空间，用于具有缓慢歧管的驱动系统；估计非强制性行驶方程的Koopman本征函数；仅基于提升和阻力的嘈杂观察，对流体弹球系统的模型预测控制。

联合学习（FL）是以分散的方式共同训练机器学习算法的范式。 FL中的大多数研究都集中在基于神经网络的方法上，但是，由于克服算法的迭代和添加性特征的挑战，在联合学习中基于XGBoost的方法（例如XGBOOST）在联合学习中没有得到反应。基于决策树的模型，尤其是XGBoost，可以处理非IID数据，这对于联合学习框架中使用的算法很重要，因为数据的基本特征是分散的，并且具有本质上非IID的风险。在本文中，我们专注于研究通过对各种基于样本量的数据偏斜方案进行实验以及这些模型在各种非IID方案下的性能，通过非IID分布的影响如何受到非IID分布的影响。我们在多个不同的数据集中进行了一组广泛的实验，并进行了不同的数据偏斜分区。我们的实验结果表明，尽管有各种分区比率，但模型的性能保持一致，并且与以集中式方式训练的模型接近或同样良好。

在线作业问题在运营研究和计算机科学中起着重要作用，这就是为什么要引起了提高其解决方案质量的极大关注的原因。由于有关输入的不完整信息，在线算法很难产生最佳解决方案。使用竞争比率测量在线算法的解决方案的质量。没有在线确定性算法可以比（2N-1）更好地实现竞争比率。已经表明，在线计算中的建议改善了在线问题的竞争比率的下限。在线计算中的建议可以解释为在线算法的其他信息，以补偿缺乏有关整个输入序列的信息。在这项研究中，我们研究了引入机器学习建议如何改善此问题的竞争比率。通过模拟机器学习算法，我们为在线分配问题提供了在线算法，该算法预先预测了整个输入。我们利用一种最佳离线算法来提供预测输入的匹配解决方案。此外，我们研究了机器学习的预测错误如何影响在线算法的竞争比率。我们利用基准数据集来执行我们的经验分析。我们表明，随着机器学习预测误差的增加，解决方案质量会降低。此外，误差的大小与输入的大小成正比。该结果类似于在线分配问题最佳确定性算法的竞争比率，该算法也取决于参数n。