过去已经表明,与解决多模式问题生成器的解决实例相比,多座丘陵策略与标准遗传算法相比有利。我们扩展了这项工作,并验证遗传算法中多样性保存技术的利用是否改变了比较结果。在两种情况下,我们这样做:(1)​​目标是找到全局最佳距离时,(2)当目标是找到所有Optima时。进行了数学分析,用于多设山丘算法,并通过实证研究进行了经验研究,以求解多模式问题生成器的实例,其中包括山丘策略以及遗传算法的数量,并使用遗传算法进行了元素。尽管小甲基元素改善了遗传算法的性能,但它仍然不如这类问题上的多尽山关闭策略。还提出了一种理想化的细分策略,并认为它的性能应接近任何进化算法在此类问题上可以做到的。
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Graph convolutional neural networks have shown significant potential in natural and histopathology images. However, their use has only been studied in a single magnification or multi-magnification with late fusion. In order to leverage the multi-magnification information and early fusion with graph convolutional networks, we handle different embedding spaces at each magnification by introducing the Multi-Scale Relational Graph Convolutional Network (MS-RGCN) as a multiple instance learning method. We model histopathology image patches and their relation with neighboring patches and patches at other scales (i.e., magnifications) as a graph. To pass the information between different magnification embedding spaces, we define separate message-passing neural networks based on the node and edge type. We experiment on prostate cancer histopathology images to predict the grade groups based on the extracted features from patches. We also compare our MS-RGCN with multiple state-of-the-art methods with evaluations on both source and held-out datasets. Our method outperforms the state-of-the-art on both datasets and especially on the classification of grade groups 2 and 3, which are significant for clinical decisions for patient management. Through an ablation study, we test and show the value of the pertinent design features of the MS-RGCN.
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电力系统容易出现各种事件(例如线路旅行和发电损失),而在情境意识,可靠性和安全性方面,对此类事件的实时识别至关重要。使用来自多个同步管理器的测量值,即相量测量单元(PMU),我们建议通过基于模态动力学提取特征来识别事件。我们将这种基于物理学的特征提取方法与机器学习结合在一起,以区分不同的事件类型。包括每个PMU的所有测量通道都允许利用各种功能,但还需要在高维空间上学习分类模型。为了解决此问题,实现了各种功能选择方法,以选择最佳功能子集。使用获得的功能子集,我们研究了两个众所周知的分类模型的性能,即逻辑回归(LR)和支持向量机(SVM),以识别两个数据集中的发电损失和线路跳闸事件。第一个数据集是从得克萨斯州2000-Bus合成网格中的模拟发电损失和线路跳闸事件中获得的。第二个是专有数据集,其标记事件是从美国的大型公用事业中获得的,涉及近500 pmus的测量。我们的结果表明,所提出的框架有望确定两种类型的事件。
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