Marta Oliva

Quantitative analysis in a heuristic evaluation experiment

In usability context of interactive systems the heuristic evaluation method is widespread. In most applications the results tend to be qualitative, describing such aspects that require some improvement for the benefit of usability. However, these qualitative results do not allow us to determine how usable it is or how it becomes an interactive system. Hence the need for quantitative results may also be very necessary in order to determine the effort that would be needed to get a sufficiently usable system. This article describes, following the idea of the UsabAIPO Project, a new experiment to obtain quantitative results after a heuristic evaluation. This new experimentation has required some variation on the original idea, working with a set of different heuristic categories, while considering the use of the score depending on severity and frequency parameters.

Building a Usable and Accessible Semantic Web Interaction Platform

Semantic Web applications take off is being slower than expected, at least with respect to “real-world” applications and users. One of the main reasons for this lack of adoption is that most Semantic Web user interfaces are still immature from the usability and accessibility points of view. This is due to the novelty of these technologies, but this also motivates the exploration of alternative interaction paradigms, different from the “traditional” Web or Desktop applications ones. Our proposal is realized in the Rhizomer platform, which explores the possibilities of the object–action interaction paradigm at the Web scale. This paradigm is well suited for heterogeneous resource spaces such as those common in the Semantic Web. Resources, described by metadata, correspond to the objects in the paradigm. Semantic web services, which are dynamically associated to these objects, correspond to the actions. The platform is being put into practice in the context of a research project in order to build an open application for media distribution based on Semantic Web technologies. Moreover, its usability and accessibility have been evaluated in this real setting and compared to similar systems.

The Rhizomer Semantic Content Management System

The Rhizomer platform is a Content Management System (CMS) based on a Resource Oriented Approach (RESTful) and Semantic Web technologies. It achieves a great level of flexibility and provides sophisticated content management services. All content is described using semantic metadata semi-automatically extracted from multimedia content, which enriches the browsing experience and enables semantic queries. A usable user interface is built on top of the CMS in order to facilitate the interaction with content and enhance it with the information provided by the associated semantic metadata. As an application scenario of the platform, its use in a media company where audio content is managed and its speech transcript semantically annotated is described.

Ontology-Based Retrieval of Human Speech

As part of the general growth and diversification of media in different modalities, the presence of information in the form of human speech in the world-wide body of digital content is becoming increasingly significant, in terms of both volume and value. We present a semantic- based search model for human speech corpora, stressing the search for meanings rather than words. Our framework embraces the complete recognition/retrieval cycle, from word spotting to semantic annotation, query processing, and search result presentation.

Building Secure Data Warehouse Schemas from Federated Information Systems

There are certain similarities between architectures for Federated Information Systems and architectures for Data Warehousing. In the context of an integrated architecture for both Federated Information Systems and Data Warehousing, we discuss how additional schema levels provide security, and operations to convert from one level to the next.

The semantic web as a newspaper media convergence facilitator

Newspapers are evolving and this causes great changes in how newspapers reach their consumers, but also in how newspapers work internally. Advanced computerised support is needed in order to cope with the new needs, which require that machines are aware of a greater part of the underlying semantics. Ontologies and Semantic Web technologies are clear candidates for web-wide semantics. However, newspapers have made great investments in their current news management systems and their wish is to undertake a smooth transition. Our proposal is to build an ontological framework based on existing journalism and multimedia standards. These standards are based on XML technologies. Therefore, we have developed a generic XML Schema to OWL mapping, complemented with an XML to RDF one. Together, they allow reusing existing metadata that, once in a semantic space, facilitates data integration, news management and retrieval. The resulting ontological framework is being applied in the Diari Segre Media Group, which produces press, radio and television content.

OPEN-HEREDEUX: open heuristic resource for designing and evaluating user experience

The need of enhancing design and evaluation of user experience exists. We propose a resource which helps to semi automate the design and evaluation of user experience.

A design process for exhibiting design choices and trade-offs in (potentially) conflicting user interface guidelines

In the last decades a huge amount of knowledge about user interface design has been gathered in the form of guidelines. Quite often, guidelines are compiled according to user interface properties (e.g. usability, accessibility) and/or application domains (e.g. Web, mobile). In many situations designers have to combine several guideline sets in order to address the specific application domain and the desired set of properties corresponding to the application under consideration. Despite the fact that the problems related to the selection of guidelines from different sources are not new, the occurrence and management of conflicting guidelines are poorly documented leaving designers with little help in order to handle conflicts in a rationale and consistent way. In this paper we revise the questions related to selection and management of conflicting guidelines and we propose a systematic approach based on design rationale tools and techniques for exhibiting choices and trade-offs when combining different guidelines sets. This paper illustrates how such as an approach can also be used to deepen the knowledge on the use of user interface guidelines recording decisions across projects in an iterative way.

Integrating Multilevel Security Policies in Multilevel Federated Database Systems

This paper describes a multilevel security policies integration methodology to endow tightly coupled federated database systems with a multilevel security system. The proposal is based on a schema integration process. It obtains, in a semi-automatic form, the ordered set of classification levels for the multilevel security system of the federation, and the translation functions between each ordered set belonging to each component database and the federated ordered set as well. The proposed methodology also includes a way to solve the problem of classification of the components of the Federated Schema generated during the integration process.

User experience specification through quality attributes

The concept of user experience includes different facets which have still not reached a consensus. On the other hand, the ISO/IEC 25010:2011 standard shows a structured quality model which permits us to obtain quality systems and software. The main aim is the specification of user experience based on the facets which are implicitly considered in the standard.