Giovanni Bracco

The role of medium size facilities in the HPC ecosystem: the case of the new CRESCO4 cluster integrated in the ENEAGRID infrastructure

Medium size HPC clusters play an important role in the HPC landscape in that they provide both the training environment for system scalability and a flexible production field for a large class of numerical problems. In this poster we present CRESCO4, the latest medium size HPC cluster purchased by ENEA, in operation since few months. CRESCO4 is part of a family of HPC systems, all integrated within ENEAGRID, a large infrastructure for cloud computing, which includes all the computational facilities installed at several ENEA sites in Italy.

High-energy neutral particle measurement system in the large helical device

The development of a high-energy neutral particle measurement system for ion temperature measurements and high-energy particle confinement analysis during neutral beam injection and ion cyclotron resonance frequency heating experiments in the large helical device (LHD) is described here. We have been improving the time-of-flight neutral particle analyzer for the LHD which had been developed in ENEA Frascati. The control and data acquisition systems were designed to be suitable for long discharges in the LHD. The horizontal and vertical movable stage is prepared to investigate pitch-angle distribution and loss cone. We have resolved many difficulties at installation, for example, the strong leakage magnetic field from the LHD and the limitations of magnetized materials near the LHD, the quench of the superconducting magnetic field, the narrow viewing port, and the fully remote control system. The preliminary results in plasma experiments are also described here.

A Parallel Code for Time-Dependent acoustic Scattering Involving Passive or Smart Obstacles

A highly parallelizable numerical method to solve three-dimensional time-dependent acoustic obstacle scattering problems involving passive or smart, furtive, realistic obstacles is presented. ‘‘Realistic’’ obstacles have complex geometries, ‘‘passive’’ obstacles do not react by taking an action to pursue a goal when hit by an incoming wave, and ‘‘smart furtive’’ obstacles, when hit by an incoming wave, pursue the goal of being undetectable by circulating a suitable pressure current on their boundaries. Incoming wave packets containing time-harmonic waves of small wavelengths when compared with the characteristic dimension of the obstacles are considered. The features of the computational method proposed to solve these scattering problems that can be exploited in a parallel and/or distributed computing environment are presented. Numerical experiments involving a simplified version of the NASA space shuttle are discussed. The websites: http://www.econ.univpm.it/ recchioni/scattering/w12, http://www.econ.univpm.it/recchioni/scattering/w14 contain animations and virtual reality applications showing some numerical experiments relative to the problems studied. A more general reference to the work of some of the authors and of their coworkers in acoustic and electromagnetic scattering is the website: http://www.econ. univpm.it/recchioni/scattering.

A Collaborative Environment for Web Crawling and Web Data Analysis in ENEAGRID.

In this document we provide an overview on the development and the integration in ENEAGRID of some tools able to download data from Web (Web Crawling), manage and display a large amount of data (Big Data), and extract from data relevant hidden information (Data Mining). We collected all these instruments inside the so called Web Crawling Project. Further, the corresponding environment, called Virtual Laboratory, is able to offer the possibility to use all these integrated tools remotely and by a simple graphical interface. A detailed description of the developed web application will be illustrated. Finally, some experimental results on the behaviour of the Web Crawling tool will be reported.