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To ensure the safety of railroad operations, it is important to monitor and forecast track geometry irregularities. A higher safety requires forecasting with higher spatiotemporal frequencies, which in turn requires capturing spatial correlations. Additionally, track geometry irregularities are influenced by multiple exogenous factors. In this study, a method is proposed to forecast one type of track geometry irregularity, vertical alignment, by incorporating spatial and exogenous factor calculations. The proposed method embeds exogenous factors and captures spatiotemporal correlations using a convolutional long short-term memory. The proposed method is also experimentally compared with other methods in terms of the forecasting performance. Additionally, an ablation study on exogenous factors is conducted to examine their individual contributions to the forecasting performance. The results reveal that spatial calculations and maintenance record data improve the forecasting of vertical alignment., (© 2023. The Author(s).)

Isolated mitral valve injury from non-penetrating cardiac trauma was low in incidence. A successfully operated case of a patient with acute mitral insufficiency from non-penetrating cardiac injury due to a traffic accident was reported and discussed. This isolated mitral valve lesion, of which the posterior leaflet was torn away from the annulus with intact chordae tendineae and papillary muscle, was very rare in the literature. And, particularly, the preoperative non-invasive findings such as echocardiogram and ACG were mostly useful and important in our case. This case was the fourth successful repaired case on blunt isolated mitral valve injury in the literature.