Neurotoxic pesticides, such as neonicotinoids, negatively affect the cognitive capacity and fitness of non-target species, and could also modify interspecific interactions. We tested whether sublethal contamination with neonicotinoid could affect foraging, colony fitness and the outcome of behavioural interactions between a native (Monomorium antarcticum) and an invasive ant species (Linepithema humile). The foraging behaviour of both ants was not affected by neonicotinoid exposure. Colonies of the invasive species exposed to the neonicotinoid produced significantly fewer brood. In interspecific confrontations, individuals of the native species exposed to the neonicotinoid lowered their aggression towards the invasive species, although their survival probability was not affected. Exposed individuals of the invasive species interacting with non-exposed native ants displayed increased aggression and had their survival probability reduced. Nonexposed individuals of the invasive species were less aggressive but more likely to survive when interacting with exposed native ants. These results suggest that non-target exposure of invaders to neonicotinoids could either increase or decrease the probability of survival according to the exposure status of the native species. Given that, in any community, different species have different food preferences, and thus different exposure to pesticides, non-target exposure could potentially change the dynamics of communities and influence invasion success.

Certain heavy-lifting applications require the coordinated movement of multiple cranes. Such tasks dramatically increase the complexity of crane operation, especially when the payload has a non-uniform shape. This paper studies the dynamic behavior of a dual-hoist bridge crane moving triangular payloads. Simulations and experiments are used to develop an understanding of the dynamic response of the system. Various inputs and system configurations are analyzed, and important response characteristics are highlighted.

Certain heavy-lifting applications require the coordinated movement of multiple cranes. Such tasks dramatically increase the complexity of crane operation, especially when the payload has a non-uniform shape. Therefore, controlling such a complex dynamic system requires skilled operators. However, even with extensive operator training, manipulating a crane with a large payload is difficult and presents serious safety hazards. This paper studies the dynamic behavior of a dual-hoist bridge crane moving triangular payloads. Test subjects used a wireless controller to move a dual-hoist crane with a triangular payload. They drove the payload through an obstacle course under various operating conditions. The time required to complete the course and the operator effort were recorded. Test runs were completed with and without input-shaping oscillation control. The result shows that using input-shaping oscillation control significantly reduces not only the task completion time but also the number of button pushes.

No abstract