This paper outlines the historical development of the wheel and rail profiles currently used on railway vehicles. It also presents the key damage mechanisms involved in wheel-rail contact and summarises the methods that have recently been developed by railway engineers to predict the level of wheel and rail damage from these mechanisms. Tools for predicting the key damage modes of wear and roll...

Investigation of vertical vibrations of a railway turnout is important in designing track components under moving loads of trains. In this paper, the turnout is simulated by a linear finite element model with modal damping. A section of the turnout has a length of 36 sleeper spans surrounding the crossing. Rails and sleepers are modeled with uniform Rayleigh-&#10Timoshenko beam elements. The ra...

The dynamics of a railway vehicle are driven by the geometry and conditions at the wheel-rail contact. Typically the condition and shape of the wheel and rail are monitored separately and off-line. The work presented here is part of ongoing research into on-line modelbased estimation of parameters in the wheel-rail contact dynamics. This paper outlines a practical approach to estimating a nonli...

This research has been conducted to establish a wheel-point device and evaluate its efficiency (precision, accuracy and time) with respect to the estimation of canopy percent in a pilot Artemisia stand in Khabr region of Baft, Kerman province, Iran in 2015. Several transects with different lengths (30, 60, 90, 120, 150 and 180 m) were established using the randomized sampling block with 5 repli...

A leg-wheel robot with four mechanically separated legs and two wheels is highly mobile and stable on rough terrain. We discuss the strategy for the robot movement over large rough terrain, classifying topographical features into 13 patterns of combined terrain surface. To traverse all classified terrain, we propose three adaptive gaits: (1) Step-up gait in which frontfoot landing is higher tha...

Investigation of vertical vibrations of a railway turnout is important in designing track components under moving loads of trains. In this paper, the turnout is simulated by a linear finite element model with modal damping. A section of the turnout has a length of 36 sleeper spans surrounding the crossing. Rails and sleepers are modeled with uniform Rayleigh- Timoshenko beam elements. The rail...

Background and aim: Eczema is a common inflammatory skin disease. Although history and physical examination are important in diagnosis of allergen, because of extent of environmental allergens, those are not simply recognized. The objective of this study was to determine allergens in patients with contact or atopic dermatitis referred to Razi hospital.Materials and Meth...

contact dermatitis is frequent skin pathology and eyelids are one of the more frequent locations of this pathology. the objective of the present work was to study the population distribution of periocular dermatitis, determine the allergens which most frequently indicate positive in patch tests and in provocative use tests, and analyse the clinical relevance of the positive tests. patients with...

• A systematic study with new insights into wheel-rail flange squeal is carried out. Well-controlled in-situ experiments are conducted for measurements. An integrated transient model proposed and validated analysis. The intakes 3D scanning irregularity data reappearance. Mechanism of studied by discussion on identified critical factors. Wheel-rail noise during train turning has been a tricky pr...

A novel approach is proposed for the modeling of rigid-wheel and soft-soil interaction to efficiently compute normal and shear stress distributions in the contact area. The authors propose a velocity field in the vicinity of the contact area based on the physical nature of the problem. Thereupon, the incremental changes to the stress field are computed by resorting to elastoplasticity theory an...