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Big Data technology has discarded traditional data modeling approaches as no longer applicable to distributed data processing. It is, however, largely recognized that Big Data impose novel challenges in data and infrastructure management. Indeed, multiple components and procedures must be coordinated to ensure a high level of data quality and accessibility for the application layers, e.g., data analytics and reporting. In this paper, the third of its kind co-authored by members of IFIP WG 2.6 on Data Semantics, we propose a review of the literature addressing these topics and discuss relevant challenges for future research. Based on our literature review, we argue that methods, principles, and perspectives developed by the Data Semantics community can significantly contribute to address Big Data challenges.

The article provides the highlights of the Cross-Language Evaluation Forum (CLEF) 2012 Conference on Information Access Evaluation meets Multilinguality, Multimodality, and Visual Analytics held in Rome, Italy, from September 17 to 20. The conference was attended by more than 190 people. Keynote speaker Tobias Schreck discussed the application of visual analytics in document repositories.

In complex emergency/disaster scenarios, persons from teams from various emergency-response organizations collaborate to achieve a common goal. In these scenarios, the use of smart mobile devices and applications can improve the collaboration dynamically. The lack of basic interaction principles can be dangerous, as it could increase the level of disaster or can make the efforts ineffective. This paper examines the main results of the project WORKPAD finished in December 2009. WORKPAD worked on a two-level architecture to support rescue operators during emergency management. The use of a user-centered design methodology during the entire development cycle has guaranteed that the architecture and resulting system meet end-user requirements. The feasibility of its use in real emergencies is also proven by a demonstration showcased with real operators. The paper includes qualitative and quantitative results and presents guidelines that can be useful in developing emergency-management systems.

Data quality is becoming an increasingly important issue in environments characterized by extensive data replication. Among such environments, this article focuses on cooperative information systems (CISs), for which it is very important to declare and access quality of data. The article describes a general methodology for evaluating quality of data, and the design of an architectural component, named quality factory, that implements quality evaluation of XML data. The detailed design and implementation of a further service, named data quality broker, are presented. The data quality broker accesses data and related quality distributed in the CIS and improves quality of data by comparing different copies present in the system. The data quality broker has been implemented as a peer-to-peer service and a set of experiments on real data show its effectiveness and performance behavior.

The continual growth of the Global Information Infrastructure (GII) prompts dramatic changes in both the types of information involved, and the kind of people who access it. In this paper, we briefly survey the most recent results with respect to the User Interface area, as emerged from the work presented at the fourth edition of the Conference on Advanced Visual Interfaces (AVI'98), focusing on interaction with large information spaces, multimodality, and usability issues.

We propose a framework for database querying providing the user with several interaction paradigms based on different (i.e., form-based, diagrammatic, iconic, and hybrid) visual representations of the database. A unified model, namely the Graph Model, is used as the common underlying model, in terms of which databases expressed in the most common data models can be easily converted. Graph Model databases can be queried by means of the multiparadigmatic interface. The semantics of the query operations is formally defined in terms of the Graphical Primitives. Such a formal approach enables the query manager to maintain the same query consistently in any representation. In the proposed multiparadigmatic environment, the user can switch from one interaction paradigm to another during query formulation, so that the most suitable query representation can be found.

Visual query systems (VQSs) are query systems for databases that use visual representations to depict the domain of interest and express related requests. VQSs can be seen as an evolution of query languages adopted into database management systems; they are designed to improve the effectiveness of the human–computer communication. Thus, their most important features are those that determine the nature of the human–computer dialogue. In order to survey and compare existing VQSs used for querying traditional databases, we first introduce a classification based on such features, namely the adopted visual representations and the interaction strategies. We then identify several user types and match the VQS classes against them, in order to understand which kind of system may be suitable for each kind of user. We also report usability experiments which support our claims. Finally, some of the most important open problems in the VQS area are described.

The advent of graphical workstations has led to a new generation of interaction tools in database systems, where the use of graphics greatly enhances the quality of the interaction. Yet, Visual Query Languages present some limitations, deriving partly from their own paradigm and partly from the available technology. One of the basic drawbacks is the lack of formalization, in contrast to the well-established traditional languages. In this paper we propose a theoretical framework for visual interaction with databases, having a particular kind of hypergraph, the Structure Modeling Hypergraph (SMH), as a representation tool, able to capture the features of existing data models. SMHs profit from the basic property of diagrams while overcoming their limitations. Notable characteristics of SMHs are: uniform and unified representation of intensional and extensional aspects of databases, direct representation of containment relationships, and immediate applicability of direct manipulation primitives. SMHs are not a new data model but a new representation language that provides the syntactic rules for describing the structuring mechanisms of data models. SMHs can be queried by formal systems closed under queries. Copyright 1995, 1999 Academic Press

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