• Build a 3D wheel-rail transient explicit rolling contact FE model considering rail spalling failure. Investigate dynamic response characteristics when the train passes area under different conditions. Use wavelet transform technique to process signal and detect defects dynamically. The length of has great influence on interaction its limit is found. Rail typical form fatigue (RCF), difficult ...

DLR’s Vehicle System Dynamics group has a long tradition in the computational analysis of railway vehicles’ dynamics. The group’s main focus used to be on the development of software tools for the efficient analysis of general mechanical systems with a special emphasis on the dynamics of ground vehicles like automobiles, railway vehicles and aircraft landing gears. The respective research activ...

Despite significant efforts throughout the last decades, the mechanisms behind the formation of squats — a form of rolling contact fatigue (RCF) damage in rails — are not fully understood. Proposed causes of initiation involve, but are not limited to, small initial rail surface irregularities which yield high contact stresses, rail corrugation and varying friction conditions. To complicate matt...

In this paper, effect of uncertainty fastening system properties on the wheel/rail dynamic force (WRDF) was investigated. For purpose, two deterministic and epistemic models vehicle/track interaction were developed, using finite element method. Validity results obtained from shown through comparison between model those field tests. The effects WRDF in different axle loads, vehicle speeds, rail ...

Commuter rail systems are widely regarded as an effective transportation alternative to reduce energy consumption and emissions in large urban areas. Use of commuter rail systems in the United States is on the rise, with annual ridership increasing by 28 percent between 1997 and 2007 [1]. With growing concerns about the sustainability and environmental impacts of transportation, modal energy ef...

This study aims to investigate factors that contribute to the differences in incidence of hypertension between different regions in Japan, by accounting for not only individual lifestyles, but also their living environments. The target participants of this survey were individuals who received medical treatment for hypertension, as well as hypertension patients who have not received any treatmen...

The strength design of the high-speed maglev train lacks specific methods, and analysis mainly refers to standards traditional wheel-rail technology, which cannot meet requirements development. An efficient structure evaluation method for trains is proposed based on Shanghai system. combined operation conditions are first constructed by linear superposition combination single conditions. Throug...

The incidence function model (IFM) uses area and connectivity to predict metapopulation dynamics. However, false absences and missing data can lead to underestimates of the number of sites contributing to connectivity, resulting in overestimates of dispersal ability and turnovers (extinctions plus colonizations). We extend estimation methods for the IFM by using a hierarchical Bayesian model to...