A taxonomic study was conducted to clarify the relationships of two bacterial populations belonging to the genus Weissella. A total of 39 strains originating mainly from Malaysian foods (22 strains) and clinical samples from humans (9 strains) and animals (6 strains) were analysed using a polyphasic taxonomic approach. The methods included classical phenotyping, whole-cell protein electrophores...

We present a case study in the design of an autonomous robotic software subsystem for managing mission execution and discrete traffic interaction in the 2007 DARPA Urban Challenge. Its role is reviewed in the context of the overall software system that controls “Boss”, Tartan Racing’s winning entry in the competition. Design criteria are presented, followed by the application of design principl...

The idea that somemedical procedures are unnecessary and can do more harm than good is as old as medicine itself. In Mesopotamia 38 centuries ago, Hammurabi proclaimed a law threatening overzealous surgeons with the loss of a hand or an eye. In 1915, at the height of a surgical vogue for prophylactic appendicectomy, Ernest Codman offended his Boston colleagues with a cartoon (figure⇓) mocking t...

In November 2007 the international competition DARPA Urban Challenge took place on the former George Airforce Base in Victorville, California to significantly promote the research and development on autonomously driving vehicles for urban environments. In the final race only eleven out of initially 89 competitors participated and “Boss” from Carnegie Mellon University succeeded. This paper summ...

A novel probabilistic perception algorithm is presented as a real-time joint solution to data association, object tracking, and object classification for an autonomous ground vehicle in all-weather conditions. The presented algorithm extends a Rao-Blackwellized Particle Filter originally built with a particle filter for data association and a Kalman filter for multi-object tracking (Miller et a...

The DARPA Urban Challenge required robots to drive 60 miles on suburban roads while following the rules of the road in interactions with human drivers and other robots. Tartan Racing’s Boss won the competition, completing the course in just over 4 hours. This paper describes the software infrastructure developed by the team to support the perception, planning, behavior generation, and other art...

Robot navigation in urban environments requires situational reasoning. Given the complexity of the environment and the behavior specified by traffic rules, it is necessary to recognize the current situation to impose the correct traffic rules. In an attempt to manage the complexity of the situational reasoning subsystem, this paper describes a finite state machine model to govern the situationa...

We examine how accretion on to T Tauri stars may be modulated by a time-dependent ‘magnetic gate’ where the inner edge of the accretion disc is disrupted by a varying stellar field. We show that magnetic field variations on time-scales ≪ 10 yr can modulate the accretion flow, thus providing a possible mechanism both for the marked photometric variability of T Tauri stars and for the possible co...

Algebraic multigrid (AMG) is an efficient multilevel method for solving large sparse linear systems obtained from the discretisation of scalar elliptic partial differential equations. AMG can be used to compute powerful preconditioners for use with Krylov subspace methods. We report on the design and development of an efficient, robust and portable implementation of AMG that is available as pac...