The concept of self-replicating machines was introduced more than fifty years ago by John von Neumann. However, to our knowledge a fully autonomous selfreplicating robot has not been implemented until now. Here we describe a fully autonomous prototype that demonstrates robotic self replication. This work builds on our previous results in remote-controlled robotic replication and semi-autonomous...

It is generally known that the groove on tire tread can increase friction force between and road surface under wet condition because of improvement drainage performance. Although wheel actual railway rolling stocks have a turning trace like tread, characteristics tangential contact wheel/rail not clarified in detail. In this study, measurement using pair small cylindrical specimens was carried ...

Tire-tread material has a zinc (Zn) content of about 1 wt %. The quantity of tread material lost to road surfaces by abrasion has not been well characterized. Two approaches were used to assess the magnitude of this nonpoint source of Zn in the U.S. for the period 1936-1999. In the first approach, tread-wear rates from the automotive engineering literature were used in conjunction with vehicle ...

Patients with epidermolysis bullosa (EB) provide a unique and complex challenge for the anaesthesiologist. This is rare inherited group of diseases characterized by excessive fragility skin mucous membranes. These patients tolerate compressive forces to but barely friction shearing forces. Major challenges anaesthetist include establishing adequate monitoring without damaging skin, issues posit...

The subsurface defect in the wheel tread caused from Rolling Stock Fatigue (RCF) has become more danger in high speed railway. The conventional UT and phased array UT have deficiency to find the subsurface defect from the tread surface because of limitation of ultrasonic near field. In this paper, the subsurface defect is studied by simulation and experimental results with ultrasonic technique....

This paper discusses the use of Linear Mixed Models (LMM) and Generalized Linear Mixed Models (GLMM) to predict the wear and damage trajectories of railway wheelsets for a fleet of modern multiple unit trains. The wear trajectory is described by the evolution of the wheel flange thickness, the flange height and the tread diameter; whereas the damage trajectory is assessed through the probabilit...

The deformation of an erythrocyte has been observed microscopically in the shear flow to detect the sublethal damage of an erythrocyte in vitro. A rheoscope system has been manufactured to observe the deformation of the suspended erythrocytes in the shear flow. The rheoscope consists of a pair of parallel disks and an inverted phasecontrast microscope. The human erythrocytes were suspended in t...

BACKGROUND Prevention of slipping accidents requires provision of adequate friction through the use of suitable combinations of footwear and underfoot surfaces. Shoe sole tread groove is one of the important factors on friction coefficient during walking. OBJECTIVE To measure the effect of different shoe sole tread groove depths and different surfaces on the required quotient of friction (Q),...