The main design criteria of ballasted railway tracks include rail deflections, rail bending stresses, rail wheel contact stresses, sleeper bending moments and ballast sleeper contact pressures. Numerous criteria have been defined for the design of ballasted railway tracks owing to the various mechanical properties of track components and their complex interaction. Therefore, railway track desig...

AIM To examine sleep quality and its determinants among people with type 2 diabetes mellitus (T2DM). METHODS This is a cross-sectional study conducted among diabetic patients referring to Ardabil diabetes clinic in Northwest of Iran. Information on sleep quality was collected using Pittsburg Sleep Quality Index (PSQI). A questionnaire was used to collect data on sociodemographic lifestyle fac...

The role of the media in the creation of distrust is much debated in political communication. Will negative news, for example, relentless attacks on political authorities, result in political cynicism or in a stimulation effect? By and large the media may stimulate political participation,but it is less clear when negative news will nullify this effect. Negative news may not only have short-ter...

A constitutive model based on plasticity theory with a non-associative flow rule has been developed. The model is formulated in terms of sleeper displacements and forces, and includes hardening and softening controlled by irreversible transversal (lateral and longitudinal) sleeper displacements. The model has been calibrated using results from lateral and longitudinal ballast resistance tests c...

A novel concept of polymer railway sleeper is proposed in this study that has the potential to meet static performance requirements within cost hardwood timber. The existing challenges composite sleepers, such as low or high cost, can be overcome using innovative concept. Such a proclamation proven through limit state design criteria and series experimentations. Results show polyurethane foam a...

Billions of sleepers are used on railways around the world today. As importance in transportation sector is increasing, demand for also increasing. Although wooden and steel were rail systems past, today most widely sleeper type reinforced concrete sleepers. Among these sleepers, pre-stressed used, popular that can be produced many countries. The two main production methods ribbed system non-ri...

in this research, the structural behavior of timber and concrete sleepers in a standard railway turnout is evaluated, in the case of raising speed. in approaching this evaluation, current practices in the structural analysis of sleepers are surveyed and then, the sensitivity analysis with abaqus software is made based on selected criteria (bending and shear stresses as well as contact pressure)...

The objective of this study was to describe sleep patterns in patients with heart failure (HF) and analyze associations between sleep and the following variables: gender, age, fatigue, fatigue on exertion, physical activity, functional class, drug therapy, dyspnea, and body mass index. The nonprobability sample consisted of 400 patients (mean age 57.8 years; 64.8% were men, average schooling of...