Parallel and Distributed Computing in Education (Invited Talk)

The natural world is certainly not organised through a central thread of control. Things happen as the result of the actions and interactions of unimaginably large numbers of independent agents, operating at all levels of scale from nuclear to astronomic. Computer systems aiming to be of real use in this real world need to model, at the appropriate level of abstraction, that part of it for which it is to be of service. If that modelling can reflect the natural concurrency in the system, it ought to be much simpler Yet, traditionally, concurrent programming is considered to be an advanced and difficult topic - certainly much harder than serial computing which, therefore, needs to be mastered first. But this tradition is wrong. This talk presents an intuitive, sound and practical model of parallel computing that can be mastered by undergraduate students in the first year of a computing (major) degree. It is based upon Hoare's mathematical theory of Communicating Sequential Processes (CSP), but does not require mathematical maturity from the students - that maturity is pre-engineered in the model. Fluency can be quickly developed in both message-passing and shared-memory concurrency, whilst learning to cope with key issues such as race hazards, deadlock, livelock, process starvation and the efficient use of resources. Practical work can be hosted on commodity PCs or UNIX workstations using either Java or the Occam multiprocessing language. Armed with this maturity, students are well-prepared for coping with real problems on real parallel architectures that have, possibly, less robust mathematical foundations

Study of the Behavior of Offshore Wind Turbine Monopiles under Monotonic and Cyclic Lateral Loading

peer reviewedThis chapter presents a study on the behavior of monopiles for offshore wind turbines under lateral loading, with a special focus on monopiles grounded in clayey soils. The behavior of the monopile is studied in terms of soil reaction curve. The analysis focuses on three main points: under monotonic loading, we have analyzed the effect of the loading velocity on the response of the foundation. Simulations have clearly shown the influence of loading velocity on the behavior at the soil-pile interface. Then, based on an anisotropic constitutive law, the influence of both types of anisotropy (initial and induced by loading) has been studied. Finally, we have considered a nonalternating cyclic loading, in order to analyze the effect of cyclical accumulation on force-displacement curves of monopiles