Two different spray application methods were compared in three vine varieties and different crop stages. A conventional spray application with a constant volume rate per unit ground area (l•ha1) was compared with a variable rate application method designed to compensate electronically measured variations of canopy dimensions. An air-blast sprayer with individual multi-nozzle spouts was fitted u...

We present a task model for adaptive real-time tasks in which a task’s execution rate requirements are allowed to change at any time. The model, variable rate execution (VRE), is an extension of the rate-based execution (RBE) model. We relax the constant execution rate assumption of canonical realtime task models by allowing both the worst case execution time (WCET) and the period to be variabl...

Recovery from failures can be achieved through asyn-chronous checkpointing and optimistic message logging. These schemes have low overheads during failure-free operations. Central to these protocols is the determination of a maximal consistent global state, which is recoverable. Message semantics is not exploited in most existing recovery protocols to determine the recoverable state. We propose...