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The information explosion the world has witnessed in the last two decades has forced businesses to adopt a data-driven culture for them to be competitive. These data-driven businesses have access to countless sources of information, and face the challenge of making sense of overwhelming amounts of data in a efficient and reliable manner, which implies the execution of read-intensive operations. In the context of this challenge, a framework for the dynamic read-optimization of large dimensional datasets has been designed, and on top of it a workload-driven mechanism for automatic materialized view selection and creation has been developed. This paper presents an extensive description of this mechanism, along with a proof-of-concept implementation of it and its corresponding performance evaluation. Results show that the proposed mechanism is able to derive a limited but comprehensive set of views leading to a drop in query latency ranging from 80% to 99.99% at the expense of 13% of the disk space used by the base dataset. This way, the devised mechanism enables speeding up query execution by building materialized views that match the actual demand of query workloads.

Social media encapsulates one of the most prominent human information behaviours that has rapidly evolved to create a new data-driven paradigm that uses data-intensive digital environments to communicate, collaborate, express opinions and support decisions. This has established social media as a unique information asset for value co-creation as it empowers individuals to actively express opinions and sentiment on all facets of interactions with an external entity. Despite recent research on the theoretical underpinnings of social media in open service innovation, practical demonstrations of actionable insights are limited, mainly due to the voluminous and unstructured nature of social media data. We address this limitation by presenting an evidence-based study that uses machine learning algorithms to generate actionable insights of strategic value from this data-driven paradigm. These outcomes provide fresh perspectives and new thinking that advances social media as an emergent information asset for end-to-end open innovation and incremental value co-creation.

Realiza um estudo comparativo entre diferentes modelos de organização de acervos eletrônicos. A pesquisa identificou três tipos: desconcentrado, concentrado e híbrido. A sua adoção é dependente de contexto e de fatores estratégicos. O Modelo Desconcentrado apresenta-se como o mais adequado na relação custo-benefício; o Modelo Concentrado, o de melhor governança, embora utilize, geralmente, tecnologias com padrões não abertos; e o Modelo Híbrido, em longo prazo, o mais flexível e menos vulnerável frente a evoluções tecnológicas, contudo, o mais dispendioso. A comparative study between different models for organization of large electronic collections is shown. The research identified three types of organization: decentralized, centralized and hybrid. The adoption of each one depend on context and strategic factors. The decentralized model is more appropriate due to the better cost-benefit relationship; the concentrated model offers more governance, but it uses proprietary standard technologies; and the hybrid model in the long term is the most flexible and least vulnerable to changing technologies, although it is the most expensive.

In recent years, dynamic multi-layer networks have emerged. Unlike regular networks these multi-layer networks allow users and other networks to interface on different technology layers. While path finding on a single layer is currently well understood, path finding on multi-layer networks is far from trivial. Even the constraints (the possible incompatibilities) are not always clear. This paper proposes a model for multi-layer circuit-switched computer networks, based on ITU-T G.805 and GMPLS standards. Furthermore, it defines a simple algebra that can be used to verify the validity of network connections through such networks. The most important contribution of our model and algebra is that they are technology independent: they can describe any circuit-switched network technology without modifications or tuning to the model and algebra. The model and algebra have been implemented in a syntax and network tool, which are briefly discussed. © 2008 Dr. Freek Dijkstra.

There is an increasing demand for the exchange of important product and manufacturing information in a computer interpretable way. Large manufacturing companies are dependent on having access to the necessary information electronically. If they do not get information about their manufacturing resources from their vendors, they will buy their resources elsewhere, or they will have to create the information themselves. In the end, the cost of the manufactured products will increase to accommodate the cost increase from having to create, integrate, and maintain this information. In order to solve this problem, the use of international standards for product data is required. One area where such a standard is required is the area of cutting tools. This thesis describes the requirements for an international standard for the representation and exchange of cutting tool information and the resulting information model together with necessary reference data. The representation of cutting tool information using an international standard requires a generally applicable information model which is used together with a reference data library. The reference data provides the explicit, unambiguous concepts necessary for successful information exchange. ISO 13399, the international standard that is the result of this research project, uses P-Lib (ISO 13584) to define its reference data. To successfully use P-Lib in this way, requires some basic assumptions to be made, since P-Lib is originally developed for component catalogs. As a result of the chosen representation technique, the standard is capable of accommodating current and future developments of cutting tools, e.g. multi function tools. QC 20100901

In recent years, dynamic multi-layer networks have emerged. Unlike regular networks these multi-layer networks allow users and other networks to interface on different technology layers. While path finding on a single layer is currently well understood, path finding on multi-layer networks is far from trivial. Even the constraints (the possible incompatibilities) are not always clear. This paper proposes a model for multi-layer circuit-switched computer networks, based on ITU-T G.805 and GMPLS standards. Furthermore, it defines a simple algebra that can be used to verify the validity of network connections through such networks. The most important contribution of our model and algebra is that they are technology independent: they can describe any circuit-switched network technology without modifications or tuning to the model and algebra. The model and algebra have been implemented in a syntax and network tool, which are briefly discussed. © 2008 Dr. Freek Dijkstra.