Research on robots that accompany humans is being continuously studied. The Pet-Bot provides walking-assistance and object-carrying services without any specific controls through interaction between the robot and the human in real time. However, with Pet-Bot, there is a limit to the number of robots a user can use. If this limit is overcome, the Pet-Bot can provide services in more areas. There...

We present a parallelization method based on message passing interface (MPI) for a Monte Carlo program for twodimensional and three-dimensional (3-D) simulation of ion implantations. We use a master–slave strategy where the master process synchronizes the slaves and performs the input–output operations, while the slaves perform the physical simulation. For this method the simulation domain is g...

The investigation of medieval slavery is still rooted in an approach first laid down by the likes of Adam Smith and John Millar over two hundred years ago. They conceptualised history as a series of stages through which societies moved, driven by the motor of increasing economic sophistication. In this conceptualisation, slavery was an economic institution and its decline in Britain during the ...

Manumission, the freeing of a slave from bondage, has served as a powerful incentive for slaves throughout history. It was common enough in ancient times that economic historians have gone as far as to describe the Roman labor system as a functioning labor market: manumission was common enough that it encouraged slaves to work cooperatively with their owners. This paper develops a simple contra...