Summary. Dispersing swarms of robots to cover an unknown, potentially hostile area is useful to setup a sensor network for surveillance. Previous research assumes relative locations (distance and bearing) of neighboring robots are available to each robot through sensors. Many robots are too small to carry sensors capable of providing this information. We use wireless signal intensity as a rough approximation of distance to assist a large swarm of small robots in dispersion. Simulation experiments indicate that a swarm can effectively disperse through the use of wireless signal intensities without knowing the relative locations of neighboring robots.

This report describes strategies to increase the reactive surfaces of integrated gold nanoparticles (AuNPs) by employing two different types of host materials that do not possess strong electrostatic and/or covalent interactive forces. These composite particles are then utilized as highly reactive and recyclable quasi-homogeneous catalysts in a CC bond forming reaction. The use of mesoporous TiO 2 and poly(N-isopropylacrylamide), PNIPAM, particles allows for the formation of relatively small and large guest AuNPs and provides the greatly improved stability of the resulting composite particles. As these AuNPs are physically incorporated into the mesoporous TiO 2 (i.e., supported AuNPs) and PNIPAM particles (i.e., encapsulated AuNPs), their surfaces are maximized to serve as highly reactive catalytic sites. Given their increased physicochemical properties (e.g., stability, dispersity, and surface area), these composite particles exhibit notably high catalytic activity, selectivity, and recyclability in the homocoupling of phenylboronic acid in water and EtOH. Although the small supported AuNPs display slightly faster reaction rates than the large encapsulated AuNPs, the apparent activation energies (E a) of both composite particles are comparable, implying no obvious correlation with the size of guest AuNPs under the reaction conditions. Investigating the overall physical properties of various composite particles and their catalytic functions, including the reactivity, selectivity, and E a , can lead to the development of highly practical quasi-homogeneous catalysts in green reaction conditions.

We study the problem of dispersing a group of small robots in an unknown environment. The objective is to cover the environment as much as possible while staying within communications range. We assume there is no central control, the environment is unknown and with complex obstacles, the robots operate without any central control, and have only limited communications with other robots and limited sensing capabilities. We present algorithms and validate them experimentally in the Player/Stage simulation environment.

No abstract