Checkpoint and run-time adaptation with pluggable parallelisation

Enabling applications for computational Grids requires new approaches to develop applications that can effectively cope with resource volatility. Applications must be resilient to resource faults, adapting the behaviour to available resources. This paper describes an approach to application-level adaptation that efficiently supports application-level checkpointing. The key of this work is the concept of pluggable parallelisation, which localises parallelisation issues into multiple modules that can be (un)plugged to match resource availability. This paper shows how pluggable parallelisation can be extended to effectively support checkpointing and run-time adaptation. We present the developed pluggable mechanism that helps the programmer to include checkpointing in the base (sequential). Based on these mechanisms and on previous work on pluggable parallelisation, our approach is able to automatically add support for checkpointing in parallel execution environments. Moreover, applications can adapt from a sequential execution to a multi-cluster configuration. Adaptation can be performed by checkpointing the application and restarting on a different mode or can be performed during run-time. Pluggable parallelisation intrinsically promotes the separation of software functionality from fault-tolerance and adaptation issues facilitating their analysis and evolution. The work presented in this paper reinforces this idea by showing the feasibility of the approach and performance benefits that can be achieved.(undefined

An aspect-oriented approach to fault-tolerance in grid platforms

Migrating traditional scientific applications to computational Grids requires programming tools that can help programmers to update application behaviour to this kind of platforms. Computational Grids are particularly suited for long running scientific applications, but they are also more prone to faults than desktop machines. The AspectGrid framework aims to develop methodologies and tools that can help to Grid-enable scientific applications, particularly focusing on techniques based on aspect-oriented programming. In this paper we present the aspect-oriented approach taken in the AspectGrid framework to address faults in computational Grids. In the proposed approach, scientific applications are enhanced with fault-tolerance capability by plugging additional modules. The proposed technique is portable across operating systems and minimises the changes required to base applications

AspectGrid: aspect-oriented fault-tolerance in grid platforms

Migrating traditional scientific applications to computational Grids requires programming tools that can help programmers update application behaviour to this kind of platforms. Computational Grids are particularly suited for long running scientific applications, but they are also more prone to faults than desktop machines. The AspectGrid framework aims to develop methodologies and tools that can help Grid-enable scientific applications, particularly focusing on techniques based on aspect-oriented programming. In this paper we present the aspect-oriented approach taken in the AspectGrid framework to address faults in computational Grids. In the proposed approach, scientific applications are enhanced with fault-tolerance capability by plugging additional modules. The proposed technique is portable across operating systems and minimises the changes required to base applications

Beyond relational databases: preserving the data

Relational databases are one of the main technologies supporting information assets in today’s organizations. They are designed to store, organize and retrieve digital information, and are such a fundamental part of information systems that most would not be able to function without them. Very often, the information contained in databases is irreplaceable or prohibitively expensive to reacquire; therefore, steps must be taken to ensure that the information within databases is preserved. This paper describes a methodology for long-term preservation of relational databases based on information extraction and format migration to a preservation format. It also presents a tool that was developed to support this methodology: Database Preservation Toolkit (DBPTK), as well as the processes and formats needed to preserve databases. The DBPTK connects to live relational databases and extracts information into formats more adequate for long-term preservation. Supported preservation formats include the SIARD 2, created by a cooperation between the Swiss Federal Archives and the E-ARK project that is becoming a standard in the area. DBPTK has a flexible plugin-based architecture enabling its use for other purposes like database upgrade and database migration between different systems. Presented real case scenarios demonstrate the usefulness, correctness and performance of the tool.The initial E-ARK project was in part supported by the European Commission within the Competitiveness and Innovation Programme 2007–2013, Grant Agreement no. 620998 under the Policy Support Programme

AOmpLib: an aspect library for large-scale multi-core parallel programming

This paper introduces an aspect-oriented library aimed to support efficient execution of Java applications on multi-core systems. The library is coded in AspectJ and provides a set of parallel programming abstractions that mimics the OpenMP standard. The library supports the migration of sequential Java codes to multi-core machines with minor changes to the base code, intrinsically supports the sequential semantics of OpenMP and provides improved integration with object-oriented mechanisms. The aspect- oriented nature of library enables the encapsulation of parallelism-related code into well-defined modules. The approach makes the parallelisation and the maintenance of large-scale Java applications more manageable. Furthermore, the library can be used with plain Java annotations and can be easily extended with application- specific mechanisms in order to tune application performance. The library has a competitive performance, in comparison with traditional parallel programming in Java, and enhances programmability, since it allows an independent development of parallelism-related code.This work is funded by ERDF - European Regional Development Fund through the COMPETE Programme (operational programme for competitiveness) and by National Funds through the FCT - Fundação para a Ciência e a Tecnologia (Portuguese Foundation for Science and Technology) within projects FCOMP-01-0124-FEDER- 011413 and FCOMP-01-0124-FEDER-010152

Implementing an openMP-like standard with AspectJ

This paper presents an aspect-oriented library, coded in AspectJ, that aims to mimic the OpenMP standard for multicore program- ming in Java. Building the library on top of AspectJ intrinsically supports the sequential semantics of OpenMP. The library enables the use of parallelism related constructors in object-oriented sys- tems due to better compatibility with inheritance, making it more suitable to introduce parallelism into object-oriented frameworks. However, it requires more program refactoring than OpenMP di- rectives.This work is funded by ERDF - European Regional Development Fund through the COMPETE Programme (operational programme for competitiveness) and by National Funds through the FCT Fundação para a Ciência e a Tecnologia (Portuguese Foundation for Science and Technology) within project FCOMP-01-0124FEDER-010152 and FCOMP-01-0124-FEDER-011413

Fracture of the posterior malleolus: an underdiagnosed condition

The ankle joint is the most commonly injured joint during sports activity. While ankle sprains occur more frequently, ankle fractures are less common. Due to its low incidence, the isolated fracture of the posterior malleolus still represents a diagnosis challenge. This article reports a case of a female with a posterior malleolus isolated fracture after falling while performing sports activity. Clinical examination and conventional radiography were consistent with diagnosis of a simple ankle sprain and the patient was discharged with a conservative approach for lateral ankle sprain. Due to persistent pain the patient return for additional examination, which the differential diagnosis revealed an isolated fracture of the posterior malleolus without displacement of the fragment. The patient was immobilized with a suropodalic splint for 4 weeks followed by additional conservative. At the fourth month of follow-up, the patient was asymptomatic and showed good clinical and functional outcomes. This case highlights the importance of a comprehensive medical history and detailed clinical examination which may reveal pathological features that require a differential diagnosis

Construção de edifícios sustentáveis: contribuição para a definição de um processo operativo

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para a obtenção do grau de mestre em Engenharia Civil - Reabilitação de EdifíciosA presente Dissertação trata do tema da Construção Sustentável, dando especial enfoque aos Processos Operativos existentes e ao caminho a percorrer para a elaboração de um Processo Operativo enquadrado especificamente dentro dos princípios da Construção Sustentável. Através de uma revisão bibliográfica, procedeu-se ao resumo da evolução dos métodos, técnicas, materiais e fins da construção, desde o início da Humanidade até à actualidade. Apresentou-se, de seguida, o enquadramento geral da realidade nacional e internacional no que respeita à construção de edifícios sustentáveis, tendo em conta as novas premissas para a construção, os novos métodos e os novos processos associados à Construção Sustentável. Neste âmbito, foram analisadas as soluções legislativas vigentes e as propostas analíticas de diversas entidades que se debruçam sobre este tema da Construção Sustentável, enquanto vertente especializada da problemática mais abrangente intrínseca ao aperfeiçoamento e aplicação do conceito de Desenvolvimento Sustentável. Este estudo, integrando uma observação profunda do ciclo de vida do edifício e das especificidades de cada uma das fases que o integram, permitiu cumprir o já referido objectivo primordial da presente Dissertação, contribuindo para o estudo, análise e elaboração de um modelo de investigação que permita avaliar ou elaborar um Processo Operativo para a Construção Sustentável. Desta forma, a presente Dissertação representa um avanço no desenvolvimento de um Processo Operativo para a Construção Sustentável adaptado à realidade da construção em Portugal

Optimização em projecto de instalações eléctricas

Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e de ComputadoresNos anos que correm, deve-se fazer uma utilização ponderada e controlada dos recursos que o nosso planeta tem para oferecer. Principalmente, quando o bem em causa é energia. A presente dissertação aborda a importância que a energia eléctrica tem na vida do ser humano, assim como os mecanismos que lhe permitem melhor compreender como lhe dar um uso prático e inteligente, quando explorada através de instalações eléctricas. Ao criarem-se estudos que permitem optimizar e melhor aproveitar o que o meio ambiente tem para dar à humanidade, conseguem-se avanços do ponto de vista tecnológico. Mas, a viabilidade das instalações eléctricas não passa apenas pela capacidade em fazer-se uma gestão eficaz da electricidade. Existe todo um meio económico que tem de ser satisfeito, de modo a que os edíficios ou as infraestruturas possam ser criados. Torna-se urgente a realização deste tipo de estudos, que analisam as duas vertentes do problema, a eficiência energética e os custos associados, em par com a sua conjugação ideal. Nesta dissertação, é feita uma apresentação do que é e da importância que, hoje em dia, tem a conjugação óptima do binómio eficiência energética/custos de instalação. Na componente prática, estudam-se algumas das principais instalações luminotécnicas projectadas na actualidade, em função de algumas variáveis importantes, que influenciam a determinação das mais adequadas. Limita-se o estudo desenvolvido à luminotecnia por ser uma das componentes onde melhor se podem analisar os efeitos do binómio. Como resultado, apresenta-se um conjunto de cenários optimizados, resultantes da conjugação óptima do estudo em torno da eficiência energética e dos custos associados, de modo a indicar qual o melhor projecto a ser desenvolvido. Desenvolveu-se, ainda, uma aplicação informática de fácil interacção com o utilizador, onde se podem consultar as instalações mais proveitosas, em termos de viabilidade energética e económica