Transition zones in railway tracks are locations with considerable changes in the vertical stiffness of the rail support. Typically they are located near engineering structures, such as bridges, culverts, tunnels and level crossings. In such locations, the differential settlement always exists and continually grows without proper maintenance. Due to the effect of the differential settlement and...

Railway concrete sleepers have been developed and utilized in railway industry for over 50 years. Cyclic loading because of vibration on sleepers due to the train loading and the velocity of train itself and also a small percentage of bad wheels, can eventually lead to a crack network and failure of component. The objective of this study is to investigate the load carrying capacity of the selec...

Concrete sleepers have been widely used throughout the world as an alternative for timber sleepers. In North America, heavy-haul railroads have increased their use of concrete sleepers in recent years for a variety of factors. According to an international survey conducted by researchers at the University of Illinois at Urbana-Champaign (UIUC), railroad industry representatives consider center ...

Epidemiological studies of short and long sleepers have not been conducted previously. We collected socioeconomic, psychological, and polysomnographic characteristics of 6501 parents (3252 men and 3249 women) of 4036 primary school children in Guangzhou city. The study data were collected in three phases. The overall prevalence of short (5 h or less) and long (10 h or more) sleep duration was 0...

BACKGROUND Sleep disturbance in bipolar disorder can be both a risk factor and symptom of mood episodes. However, the associations among sleep and clinical characteristics, function, and quality of life in bipolar disorder have not been fully investigated. METHODS The prevalence of sleep disturbance, duration, and variability, as well as their associations with mood, function, and quality of ...

Over 50 years, a large number of research and development projects with respect to the use of cementitious and concrete materials for manufacturing railway sleepers have been significantly progressed in Australia, Europe, and Japan (Wang, 1996; Murray and Cai, 1998; Wakui and Okuda, 1999; Esveld, 2001; Freudenstein and Haban, 2006; Remennikov and Kaewunruen, 2008). Traditional sleeper materials...

BACKGROUND An inverse relation between sleep duration and body mass index (BMI) has been shown. OBJECTIVE We assessed the relation between changes in sleep duration and changes in body weight and body composition during weight loss. DESIGN A total of 98 healthy subjects (25 men), aged 20-50 y and with BMI (in kg/m(2)) from 28 to 35, followed a 2-mo very-low-energy diet that was followed by ...

Catastrophizing is present in worriers and poor sleepers. This study investigates whether poor sleepers possess a 'perseverative iterative style' which predisposes them to catastrophize any topic, regardless of content or affective valence, a style previously found to occur more commonly in worriers as compared to others. Poor (n=23) and good sleepers (n=37) were distinguished using the Pittsbu...

Background: Insufficient sleep duration and unhealthy diet are associated with weight gain. However, little is known about the association of sleep quality with dietary intake and obesity. The aim of the present study was to compare dietary intake and anthropometric indices between good and poor sleepers. Methods: In this cross-sectional study, a total of 260 femles youth aged 18-30 years were ...

The paper undertakes analysis of the dynamic impact a rail vehicle on various types railway infrastructure with particular focus phenomenon threshold effect within transition zones an engineering facility. problem locally variable stiffness infrastructure, which in turn could lead to accelerated degradation, is identified. Using analytical and numerical background, computational model presented...