in this paper effects of fractured sleepers on rail track vibration under moving wheelset have been investigated. two parallel rails of the track have been modeled as euler-bernoulli beams on elastic points as rail pads. also sleepers have been modeled as visco-elastic euler-bernoulli beams. it is assumed that, some sleepers under the rail track have been fractured and modeled by two beams. the...

The increased speed and weight of modern trains puts the components of a railway track in a highly dynamic load situation. Irregularities of the wheels and rails induce substantial dynamic loads that have to be accounted for in the procedure of designing the railway track. The concrete sleeper is an essential part of the track structure and there is a growing demand for improved analytical tool...

The proper fabrication of concrete-embedded tracks is a prerequisite for their long-term durability and their economic efficiency. Frequent defects which are caused either during fabrication or during operation are (partially) debonding between the pre-fabricated sleepers and the site-mixed concrete. This paper deals with the Pulse-ESPI-Technique as a measuring method which enables to detect th...

The purpose of the following paper is to present author’s experimental field investigations a jointless railway track subjected generated imperfection and analysis response applied static loads. An optical measurement system, Pontos, was used for dynamic track’s deflections in 3D. allow us recommend direct application this system non-contact measurement, visualization simulated defects track, a...

A numerical model to predict train induced vibrations is presented. The dynamic computation considers mutual interactions in vehicle/track coupled systems by means of a finite and discrete elements method. The rail defects and the case of out-of-round wheels are considered. The dynamic interaction between the wheel-sets and the rail is accomplished by using the non-linear Hertzian model with hy...

Early experience preserves and refines many capabilities that emerge prenatally. Here we describe another role that it plays -- establishing the neural substrate for capabilities that emerge at a much later point in development. The evidence comes from sleeper effects: permanent deficits when early experience was absent in capabilities that normally emerge long after birth. We provide evidence ...

INTRODUCTION Injuries and fatalities due to large truck and other vehicle crashes have decreased over the last decade, but motor vehicle injuries remain a leading cause of death for both the working and general populations. The present study was undertaken to determine semi truck driver and sleeper berth passenger injury risk in a moving semi truck collision using a matched-pair cohort study. ...

We introduce and investigate sleeper attacks and explore them in the context of anonymous communication, especially mix networks. Sleeper attacks can make use of the interference inherent to mix protocols. Simply by leaving his own messages in a mix network an adversary can learn about the communication of network users. Sleeper attacks can be combined with epistemic attacks, statistical disclo...

The sleeper effect in persuasion is a delayed increase in the impact of a message that is accompanied by a discounting cue. Despite a long history, the sleeper effect has been notoriously difficult to obtain or to replicate, with the exception of a pair of studies by Gruder et al. (1978). We conducted a series of 16 computer-controlled experiments and a replication of the Gruder et al. study to...

AIM The purpose of this study was to investigate whether there is a difference in pain and distress response of the child when using two different computer-controlled local analgesic delivery systems, the Sleeper One(®) and the WAND(®), and whether this was influenced by the anxiety level of the child. METHODS This randomised controlled trial was conducted among 112 children (56 girls) aged 4...