Experimental Investigation Into the Condition of Insulated Rail Joints by Impact Excitation

This paper presents a feasibility study to determine if the health condition of Insulated Rail Joints (IRJs) can be assessed by examining their dynamic response to impact excitation. First, a reference dynamic behavior is defined in the frequency domain of 50-1200 Hz based on field hammer test measurements performed on a IRJ baseline (i.e., a...

Monitoring bolt tightness of rail joints using axle box acceleration measurements

Rail joints are a weak component in railway tracks because of the large impact and wheel-rail contact forces. Every train passage contributes to the deterioration of rail joints, causing visible (e.g. battered rails) and invisible (e.g. loose bolts) damages. The invisible damage cannot be detected by the commonly performed visual inspection,...

Comparison of Data-driven Prognostics Models: A Process Perspective

Remaining useful life (RUL) prediction is crucial for the implementation of Prognostics and Health Management (PHM) systems, enabling application of predictive maintenance strategies for critical systems (e.g. in aviation, power, railway). Existing literature addresses aspects of data-driven prognostic approaches, with a predominant focus on...

Using VR-based interventions, wearable technology, and text mining to improve military and Veteran mental health

Introduction: Virtual reality (VR)-based interventions, wearable technology and text mining hold promising potential for advancing the way in which military and Veteran mental health conditions are diagnosed and treated. They have the ability to improve treatment protocol adherence, assist in the detection of mental health conditions, enhance...

Systematic Design Methodology for Prognostic and Health Management Systems to Support Aircraft Predictive Maintenance

With the rapid development in the past century, the air transport network has become one of the most important infrastructure networks for both the domestic and global economy. Within an airline, the maintenance area is responsible for planning and executing all preventive actions required to meet safety standards including maintenance tasks,...

Analysis of Urban Built Environment Impacts on Outdoor Physical Activities: A Case Study in China

Outdoor physical activities can promote public health and they are largely influenced by the built environment in different urban settings. Understanding the association between outdoor physical activities and the built environment is important for promoting a high quality of life. Existing studies typically focus on one type of outdoor activity...

A Framework for Optimal Sensor Placement to Support Structural Health Monitoring

Offshore or drydock inspection performed by trained surveyors is required within the integrity management of an in-service marine structure to ensure safety and fitness for purpose. However, these physical inspection activities can lead to a considerable increase in lifecycle cost and significant downtime, and they can impose hazards for the...

Toward a Universal Unit for Quantification of Antibiotic Resistance Genes in Environmental Samples

Surveillance of antibiotic resistance genes (ARGs) has been increasingly conducted in environmental sectors to complement the surveys in human and animal sectors under the "One-Health"framework. However, there are substantial challenges in comparing and synthesizing the results of multiple studies that employ different test methods and...

Particle filter-based fatigue damage prognosis by fusing multiple degradation models

Fatigue damage prognosis always requires a degradation model describing the damage evolution with time; thus, the prognostic performance highly depends on the selection of such a model. The best model should probably be case specific, calling for the fusion of multiple degradation models for a robust prognosis. In this context, this paper...