许多基本的低级优化问题,例如矩阵完成,相位同步/检索,功率系统状态估计和鲁棒PCA,可以作为矩阵传感问题提出。求解基质传感的两种主要方法是基于半决赛编程(SDP)和Burer-Monteiro(B-M)分解的。 SDP方法患有高计算和空间复杂性,而B-M方法可能由于问题的非跨性别而返回伪造解决方案。这些方法成功的现有理论保证导致了类似的保守条件,这可能错误地表明这些方法具有可比性的性能。在本文中,我们阐明了这两种方法之间的一些主要差异。首先,我们提出一类结构化矩阵完成问题,而B-M方法则以压倒性的概率失败,而SDP方法正常工作。其次,我们确定了B-M方法工作和SDP方法失败的一类高度稀疏矩阵完成问题。第三,我们证明,尽管B-M方法与未知解决方案的等级无关,但SDP方法的成功与解决方案的等级相关,并随着等级的增加而提高。与现有的文献主要集中在SDP和B-M工作的矩阵传感实例上,本文为每种方法的独特优点提供了与替代方法的唯一优点。
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Extracting building heights from satellite images is an active research area used in many fields such as telecommunications, city planning, etc. Many studies utilize DSM (Digital Surface Models) generated with lidars or stereo images for this purpose. Predicting the height of the buildings using only RGB images is challenging due to the insufficient amount of data, low data quality, variations of building types, different angles of light and shadow, etc. In this study, we present an instance segmentation-based building height extraction method to predict building masks with their respective heights from a single RGB satellite image. We used satellite images with building height annotations of certain cities along with an open-source satellite dataset with the transfer learning approach. We reached, the bounding box mAP 59, the mask mAP 52.6, and the average accuracy value of 70% for buildings belonging to each height class in our test set.
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