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- Gestão da informação científica e repositórios: o caso da Biblioteca Digital do IPBPublication . Pais, Clarisse; Alves, Albano; Rodrigues, OrlandoOs repositórios institucionais são estruturas de apoio à investigação que promovem a integração, a partilha e o acesso aberto à produção científica realizada e produzida pela comunidade académica. São ainda um garante para a preservação da memória intelectual e da investigação aplicada de referência. Os repositórios institucionais revestem-se de uma importância cada vez maior para as instituições enquanto produtoras de ciência e de conhecimento. Servem como plataformas gestoras de informação e contribuem para uma maior visibilidade da instituição, dos autores e da própria produção científica. Acrescem ainda fatores organizacionais, como sejam o da preservação, integração e armazenamento da informação. Graças à tecnologia digital os repositórios podem ser interoperáveis com diversos sistemas. No caso da Biblioteca Digital do Instituto Politécnico de Bragança, existe interoperabilidade com a plataforma de Avaliação do Desempenho do Pessoal Docente.
- Distributed heterogeneous computing with clOpenCLPublication . Ribeiro, Tiago Filipe Rodrigues; Afonso, Mário João da Costa; Rufino, José; Alves, AlbanoClusters of heterogeneous computing nodes provide an opportunity to significantly increase the performance of parallel and High-Performance Computing (HPC) applications, by combining traditional multi-core CPUs coupled with accelerator devices, interconnected by high throughput and low latency networking technologies. However, developing efficient applications to run in clusters that integrate GPUs and other accelerators often requires a great effort, demanding programmers to follow complex development methodologies in order to suit algorithms and applications to the new heterogeneous parallel environment. OpenCL is an open programming standard for heterogeneous computing. It suffers, however, from a major limitation: applications can only make use of the local compute devices, present on a single machine. clOpenCL (cluster OpenCL) supports the simple deployment and efficient running of unmodified OpenCL-based parallel applications that may span several cluster nodes, expanding the original single-node OpenCL model.
- Scalable multithreading in a low latency myrinet clusterPublication . Alves, Albano; Pina, António; Rufino, José; Exposto, JoséIn this paper we present some implementation details of a programming model – pCoR – that combines primitives to launch remote processes and threads with communication over Myrinet.B asically, we present the efforts we have made to achieve high performance communication among threads of parallel/distributed applications. The expected advantages of multiple threads launched across a low latency cluster of SMP workstations are emphasized with a graphical application that manages huge maps consisting of several JPEG images.
- pCoR - a protoype for resource oriented computingPublication . Pina, António; Oliveira, Vitor; Moreira, Cecília; Alves, AlbanoIn this paper we present CoR a resource oriented computing model that address the question of how to integrate user-level fine-grained multithreading, communication and coordination into a cluster of symmetrical multiprocessor computers. To support the design of complex distributed application using the proposed paradigm we built pCoR a run-time system which has new areas that represents extensions to the strict shared memory and message passing models supported by other platforms: remote operations, dynamic domains, communication ports, multithreading management, shared memory, replication and partition are some of its distinguished features. In addition, it provides a thread-safe transport communication layer to take advantage of modern high-performance commodity hardware/software like Myrinet network.
- Management design as a strategic lever to add value to corporate reputation competitiveness in higher education institutionsPublication . Maduro, Soraia; Fernandes, Paula Odete; Alves, AlbanoPurpose: The purpose of this paper is to aid the convergence of design and management as a strategic lever and innovative tool to improve corporate reputation in higher education institutions (HEIs), particularly in the Polytechnic Institute of Bragança, Portugal (IPB). Design/methodology/approach: SWOT analysis is used to identify strengths and weaknesses in the context of an organization’s internal competencies (identity) and opportunities and threats in an analysis of the organization’s external competitive context (image). Quantitative analysis was used based on questionnaires conducted with IPB community to analyse if differences exist between identity (staff) and image (students) and where there are design structures (website, visual identity, advertising and environment. Corporate character scale developed by Davies et al. (2003, 2004) was used. Findings: With the SWOT analysis, it is possible to outline IPB performance strategies that meet a positive reputation. A positive corporate reputation was found in IPB with the study of corporate character scale. It has been realized where there are differences from the point of view of identity and image, and thus, it is possible to indicate ideas of improvement to increase the competitiveness of HEIs. Research limitations/implications: The study is restricted to five schools of IPB. It would also be pertinent to broaden the scope of the stakeholders, encompassing the external community of the IPB that is extending the study to the external public, such as parents, companies, suppliers and secondary students. Practical implications: HEI competitiveness implies student recruitment and public policies. A positive reputation implies a positive brand image. Design competencies of the public higher education sector can go much further acting at the strategic level, establishing its directives of action in the markets where it operates to reflect its corporate reputation in a positive way in the mind of the consumer. Intangible assets such as identity, image and corporate reputation, appear as very valuable elements, presenting an increasing importance in the management of universities that entered a market context where sustainability requires the adoption of more entrepreneurial management guidelines. Originality value: The paper is useful for the professionals and academics in perceiving the importance of use management and strategical tools to identify HEI communication and reputation difficulties for a thorough design thinking that delineates solutions that leverage the competitiveness of service organizations such as HEIs.
- Bridging the gap between cluster and grid computingPublication . Alves, Albano; Pina, AntónioThe Internet computing model with its ubiquitous networking and computing infrastructure is driving a new class of interoperable applications that benefit both from high computing power and multiple Internet connections. In this context, grids are promising computing platforms that allow to aggregate distributed resources such as workstations and clusters to solve large-scale problems. However, because most parallel programming tools were primarily developed for MPP and cluster computing, to exploit the new environment higher abstraction and cooperative interfaces are required. Rocmeμ is a platform originally designed to support the operation of multi-SAN clusters that integrates application modeling and resource allocation. In this paper we show how the underlying resource oriented computation model provides the necessary abstractions to accommodate the migration from cluster to multicluster grid enabled computing.
- Deploying applications in multi-SAN SMP Clusters (extended version)Publication . Alves, Albano; Pina, António; Rufino, José; Exposto, JoséThe effective exploitation of multi-SAN SMP clusters and the use of generic clusters to support complex information systems require new approaches; multi-SAN SMP clusters introduce new levels of parallelism and traditional environments are mainly used to run scientific computations. In this paper we present a novel approach to the exploitation of clusters that allows integrating in a unique metaphor: the representation of physical resources, the modelling of applications and the mapping of application into physical resources. The proposed abstractions favoured the development of an API that allows combining and benefiting from the shared memory, message passing and global memory paradigms.
- Desconexão e replicação em aplicações distribuídasPublication . Alves, AlbanoO suporte à desconexão e a replicação são técnicas já bem conhecidas para aumentar a disponibilidade e a fiabilidade dos sistemas distribuídos. No entanto, até à data a prática comum tem sido a concretização destas ideias para casos pontuais, ou seja, cada programador implementa algoritmos deste tipo à sua maneira e de acordo com as características da aplicação em causa. Nesta dissertação são apresentados uma metodologia para dotar uma aplicação já existente, desenvolvida segundo o modelo Cliente-Servidor, de suporte à desconexão e um mecanismo para replicação de servidores. O suporte à desconexão é conseguido com a introdução de um agente entre o cliente e o servidor. O agente é obtido por um tradutor que processa a especificação da interface anotada com primitivas de desconexão. Estas primitivas constituem uma extensão à linguagem de especificação de interfaces. A replicação de servidores é obtida com a intercepção dos pedidos (invocações remotas) dos clientes e seu posterior reenvio através de um serviço de comunicação em grupo. O resultado deste trabalho é portanto o modelo Cliente-Agente-Servidores, para aplicação genérica a soluções desenvolvidas sem preocupações notórias no que respeita à disponibilidade e fiabilidade.
- Full-speed scalability of the pDomus platform for DHTsPublication . Rufino, José; Pina, António; Alves, Albano; Exposto, José; Lopes, Rui PedroDomus is an architecture for Distributed Hash Tables (DHTs) tailored to a shared-all cluster environment. Domus DHTs build on a (dynamic) set of cluster nodes; each node may perform routing and/or storage tasks, for one or more DHTs, as a function of the node base (static) resources and of its (dynamic) state. Domus DHTs also benefit from a rich set of user-level attributes and operations. pDomus is a prototype of Domus that creates an environment where to evaluate the architecture concepts and features. In this paper, we present a set of experiments conduced to obtain figures of merit on the scalability of a specific DHT operation, with several lookup methods and storage technologies. The evaluation also involves a comparison with a database and a P2P-oriented DHT platform. The results are promising, and a motivation for further work.
- meμ: unifying application modeling and cluster exploitationPublication . Alves, Albano; Pina, António; Rufino, José; Exposto, JoséThe increasing complexity of high-demand long-running applications has faced programmers with the need to take into account both development hardness and execution time. meu provides the flexibility to control the amount of computational and communication power being used in order to maximize resources utilization and to deliver high performance. In this paper we focus on the aspects of the paradigm that go beyond traditional message passing approaches, promoting the idea that by raising the abstraction level of programming models, programmers will make better use of the available resources with clear impact on both productivity and performance. We introduce the resource as the abstraction used to represent and manage both physical resources – nodes, memory, processors and communication technologies – and logical resources – modules, processes, tasks, threads, groups, etc. We also concentrate on the task of specifying, locating and aggregating resources in order to support the mapping of applications into the target cluster hardware and the explicit management of memory hierarchy.