Liquid queries are a flexible tool for information seeking, based on the progressive exploration of the search space; they produce "fluid" results which dynamically adapt to the shape of the query, as a liquid adapts to its container. The liquid query paradigm relies on the SeCo service mart and multi-domain query execution concepts: an expert user selects a priori the service marts relevant to the information seeking task at hand and the connections necessary to join them, and publishes such a definition in the SeCo back-end. The Liquid Query client-side interface consumes the application definition created by the expert and dynamically builds a query interface for the end-user. Such interface allows one to supply keywords to query the pre-configured service marts and offers controls for exploring the combinations computed by the SeCo execution engine. The interaction commands are based on a tabular representation of results and comprise: reordering, clustering, addition or deletion of attributes, addition of extra service marts to the query for specific items in the result set or for the entire result set, request of more results from all services or from selected ones, expansion of details on selected items, and more. The Liquid Query is equipped with multiple data visualization options suited to render multi-domain results and can be instrumented with indicators showing the quality of the result set.

With the advent of the Web, search has become the prominent paradigm for information seeking, both across the online space and within enterprises. Search frameworks and components can be used to build search-based applications in the most diverse vertical fields. This paper explores Model Driven Development and model transformations as a paradigm for developing search-based applications, considered as process- and content-intensive applications. A rich process model, obtained by extending BPMN, is proposed as the starting point of development, followed by a set of semi-automatic model transformations that lead from the conceptualization of requirements to the running code.

As the Web becomes a platform for multimedia content fruition, audiovisual search assumes a central role in providing users with the content most adequate to their information needs. A key issue for enabling audiovisual search is extracting indexable knowledge from opaque media. Such a process is heavily constrained by scalability and performance issues and must be able to flexibly incorporate specialized components for educing selected features from media elements. This paper shows how the use of a model-driven approach can help designers specify multimedia indexing processes, verify properties of interest in such processes, and generate the code that orchestrates the components, so as to enable rapid prototyping of content analysis processes in presence of evolving requirements.

Professional mashups that include complex choreographies, data mediation, and result publishing within Web pages are still affected by implementation and design practices that rely either on very simple models or on low-level scripting and programming skills of developers, thus hampering the use of mashups in business context as rapid solution to immediate problems. Indeed, industrialization of their development is still a hard objective to achieve. We propose a design methodology based on visual models to improve the quality and the productivity of service mashups and presentation of the results, thus increasing their acceptance as professional applications in the business scenario. Existing software engineering methods are combined together in an innovative mix, comprising standard business process modeling languages (namely, BPMN) to describe a high-level view of the mashup orchestration and on WebML (Web Modeling Language) to specify the detailed Web application model, including Web service interactions, hypertext navigation, event management, and rich user interfaces.

Rich Internet applications (RIAs) enable novel usage scenarios by overcoming the traditional paradigms of Web interaction. Conventional Web applications can be seen as reactive systems in which events are 1) produced by the user acting upon the browser HTML interface, and 2) processed by the server hosting the application state and logic. In RIAs, distribution of data and computation across client and server broadens the classes and features of the produced events as they can originate, be detected, notified, and processed in a variety of ways. In this work, we investigate how events can be explicitly described and coupled to the other concepts of a Web modeling language in order to specify collaborative Rich Internet applications.

This paper proposes an innovative use of a mix of networking standards and software implementation technologies for the design of industrial Human Machine Interface (HMI) systems. We describe how well known technologies and practices can be transferred from internet-based architectures to embedded systems. Several advanced features can be achieved thanks to this architecture, such as application adaptivity, interface personalization, control remotization, and multi-channel notification.