Ignacio Lamata Martínez

Reconfiguring practice: the interdependence of experimental procedure and computing infrastructure in distributed earthquake engineering.

When transitioning local laboratory practices into distributed environments, the interdependent relationship between experimental procedure and the technologies used to execute experiments becomes highly visible and a focal point for system requirements. We present an analysis of ways in which this reciprocal relationship is reconfiguring laboratory practices in earthquake engineering as a new computing infrastructure is embedded within three laboratories in order to facilitate the execution of shared experiments across geographically distributed sites. The system has been developed as part of the UK Network for Earthquake Engineering Simulation e-Research project, which links together three earthquake engineering laboratories at the universities of Bristol, Cambridge and Oxford. We consider the ways in which researchers have successfully adapted their local laboratory practices through the modification of experimental procedure so that they may meet the challenges of coordinating distributed earthquake experiments.

Process and Future of Data Integration within the European Earthquake Engineering Laboratories

AbstractIn common with many scientific disciplines, earthquake engineering research is increasingly focusing on large international collaborations to address complex problems. Data integration is a key requirement to facilitate joint research efforts and improve experimental outcomes. Development and implementation of a novel virtual database is presented, linking 22 leading European earthquake engineering research institutions, making data integration possible at a European level without the need for a large, centralized repository. The importance of establishing appropriate work methodologies to succeed in a distributed and highly heterogeneous work environment involving many dispersed institutions is described. The future of earthquake engineering data integration is considered, highlighting Semantic Web technologies as the main technological foundation to lead this integration.

Celestina-Sim: Framework to Support Distributed Testing and Service Integration in Earthquake Engineering

AbstractDistributed hybrid simulation is an approach to large-scale testing in which the system under test is split into several sub-structures which are tested or simulated in different locations. Data are passed between the sub-structures at each timestep so as to ensure that the distributed experiment realistically simulates the full system under test. This approach optimises the use of resources at different locations to achieve a more representative experiment. While different software to conduct distributed simulations exists, there are no standards and specifications to organise and plan the experiments, and as a result the different systems lack inter-operability. To address these issues, we have developed a high-level specification called Celestina, which provides a framework for conducting a distributed experiment. Celestina specifies the services to be implemented, under three main headings of networking, definition and execution, and supports the data exchange during a simulation. It does not ...

Geographically distributed hybrid testing & collaboration between geotechnical centrifuge and structures laboratories

Distributed Hybrid Testing (DHT) is an experimental technique designed to capitalise on advances in modern networking infrastructure to overcome traditional laboratory capacity limitations. By coupling the heterogeneous test apparatus and computational resources of geographically distributed laboratories, DHT provides the means to take on complex, multi-disciplinary challenges with new forms of communication and collaboration. To introduce the opportunity and practicability afforded by DHT, here an exemplar multi-site test is addressed in which a dedicated fibre network and suite of custom software is used to connect the geotechnical centrifuge at the University of Cambridge with a variety of structural dynamics loading apparatus at the University of Oxford and the University of Bristol. While centrifuge time-scaling prevents real-time rates of loading in this test, such experiments may be used to gain valuable insights into physical phenomena, test procedure and accuracy. These and other related experiments have led to the development of the real-time DHT technique and the creation of a flexible framework that aims to facilitate future distributed tests within the UK and beyond. As a further example, a real-time DHT experiment between structural labs using this framework for testing across the Internet is also presented.

A Support Platform for Distributed Hybrid Testing

Distributed hybrid testing offers a promising approach to use resources from geographically separate laboratories in a highly efficient way, to perform more complex, larger-scale tests than are possible in most individual laboratories. The method involves splitting a structure into a set of substructures (some tested physically, some modelled numerically) located in different laboratories. Simulation of the full structural response involves simultaneous testing of the substructures with feedback of data between them, requiring fast communication through computer networks. To handle systems involving rate dependence, there is a desire for test speed to approach real time. In addition to the increased difficulty of tracing errors caused by the distributed environment, organizing and planning distributed experiments creates much more complexity than in single-laboratory hybrid tests. This points to the importance of a platform to support the testing activities. This platform has been achieved by means of a specification called Celestina, created at the University of Oxford. Celestina provides a framework for conducting the experiment workflow. It provides a specification for the services to be implemented under three main headings of networking, test definition and experiment execution, and supports to data exchange during a test. It does not force any particular implementation, which can be independently developed and implemented under this framework, nor does it restrict the actual method of data exchange. In this article we discuss the design and conception of the specification as well as one implementation that has been validated through a series of substructured “numerical experiments” in partnership with the University of Kassel.

The SERIES Virtual Database: Exchange Data Format and Local/Central Databases

At the beginning of the project, the access and exchange of data within the European scientific community was highly fragmented and the diffusion of information among laboratories was not sufficient. The outcome of an inquiry performed among partner laboratories at the beginning of SERIES showed that data storage in an unstructured way was the common approach in most of the cases. Naturally, access to and elaboration of the data was restricted only to the local users, a fact leading to a very low impact of the results on practice because of their limited dissemination and the difficulties in collaboration among researchers. SERIES (Networking Activity NA1) aimed, among others, at overcoming this state by establishing a culture of preservation of data in a structured way and by facilitating data exchange and collaboration with the broader research community. A structured database in which data are stored according to a commonly agreed Exchange Data Format has been implemented at the SERIES laboratory sites; tools for the management and automatic data import have been developed to facilitate data supply from participating laboratories. The data stored in the local databases are then made publically accessible to external users by means of a Data Access Portal, hosted in the University of Patras. The elements of the so-called SERIES virtual database are here described.