In this paper, we describe modeling and control techniques for a real-world series-elastic actuated 1D hopping robot. There is an abundance of work regarding the implementation of highly simplified hopper models, with the hopes of extracting fundamental control ideas for running and hopping robots. However, real-world systems unfortunately cannot be accurately described by such simple models, a...

The beach hopper amphipod Talorchestia quoyana is not distributed homogeneously in its sandy beach habitat, but instead occurs in dense patches under large pieces of tidal debris. This marked patchiness on a scale of just a few metres may create a higher level of aggregation among hosts for the symbionts and parasites of beach hoppers. Prevalence of infection by a mermithid nematode parasite va...

We experimentally investigate the response to perturbations of circular symmetry for dense granular flow inside a three-dimensional right-conical hopper. These experiments consist of particle tracking velocimetry for the flow at the outer boundary of the hopper. We are able to test commonly used constitutive relations and observe granular flow phenomena that we can model numerically. Unperturbe...

I/O performance is an increasingly important factor in the productivity of large-scale HPC systems such as Hopper, a 153,216 core Cray XE6 system operated by the National Energy Research Scientific Computing Center. The scientific workload diversity of such systems presents a challenge for I/O performance tuning, however. Applications vary in terms of data volume, I/O strategy, and access metho...

Purpose – To examine whether the framework of management accounting transformations in Hopper et al. (2009) applies to accounting changes in the Ashanti Gold Corporation (AGC) in Ghana over 120 years from pre-colonialism to recent times. Design/methodology/approach – Mixed data sources are used, namely interviews, observations of practices, historical documentation, company reports, and researc...

Resource allocation and straggler mitigation (via “speculative” copies) are two key building blocks for analytics frameworks. Today, the two solutions are largely decoupled from each other, losing the opportunities of joint optimization. Resource allocation across jobs assumes that each job runs a fixed set of tasks, ignoring their need to dynamically run speculative copies for stragglers. Cons...

Purpose – To examine whether the framework of management accounting transformations in Hopper et al. (2009) applies to accounting changes in the Ashanti Gold Corporation (AGC) in Ghana over 120 years from pre-colonialism to recent times. Design/methodology/approach – Mixed data sources are used, namely interviews, observations of practices, historical documentation, company reports, and researc...

This research examined three explanations for the "superstitious" behavior of pigeons under frequent fixed-time delivery of food: accidental response-reward contingency, stimulus substitution, and elicited species-typical appetitive behavior. The behavior observed in these studies consisted of occasional postfood locomotion away from the food hopper, and a predominant pattern of activity direct...

In Brand Objects for Nominal Typing, we describe an implementation of a branding system for both runtime and static types. This artifact provides the extended form of Hopper, an interpreter for the Grace programming language, and extra modules which define both the dynamic objects and the modular static type checker. The extra modules extend the existing structural type checker in the provided ...