The increasing pervasiveness of software-intensive systems requires involving domain experts more directly in technological development. Visual models, expressed in semi-formal notations, can act as shared artefacts that support communication and collaboration between developers and domain experts. However, modelling with semi-formal notations can be challenging for novice modellers. This study presents an AI-infused, web-based modelling tool designed to support users in formalising domain knowledge without requiring advanced modelling skills. The tool features a block-based, domain-specific language that automatically transforms user-generated structures into semi-formal diagrams. AI-based functionalities include a diagram reader, contextual hints, natural-language instructions, and interaction logging. We evaluated the tool through a Wizard of Oz experiment with agronomists in digital agriculture, where participants completed an exploratory modelling task while interacting with AI assistance. Results reveal three key design implications: (i) adaptive AI support accommodating diverse modelling strategies, (ii) concise, actionable guidance delivered at moments of difficulty, and (iii) practice-oriented assistance that preserves user agency and supports learning-by-doing.

The notion of explainable user interfaces (XUI) has been proposed as a way to address the growing complexity and unpredictability of many UIs. A key question is whether this aspirational goal can be achieved with reasonable amounts of development effort. This paper takes React as its focus as it is one the most widely used web development frameworks. It shows through practical demonstration that the existing event mechanisms within React can be repurposed with the addition of a small amount of annotation to implement one of the proposed XUI techniques.

This paper summarises the third edition of the SYNERGY workshop on Designing and Building Hybrid Human-AI Systems, held at AVI 2026 in Venice, Italy. The workshop addresses the critical challenge of designing AI systems that genuinely augment human capabilities through meaningful combination, moving beyond approaches where humans function as mere cogs in the machine. Directly aligned with AVI 2026's theme of "Interactive Creativity: Agencies, Interfaces, and Ethics", the workshop brings together researchers and practitioners to advance both theoretical frameworks and practical implementations that preserve human agency while leveraging AI's computational power.

This workshop explores the evolving landscape of Human-AI collaboration, focusing on Advanced Visual Interfaces and Artificial Intelligence to enhance human cognition. We explore synergistic models of collaboration that merge human insights with AI capabilities, addressing ethical dimensions and practical AI applications. Our goal is to foster rich interdisciplinary dialogue and challenge existing paradigms of human-machine interaction. We aim to redefine interaction paradigms and establish new benchmarks for intelligent systems, ensuring AI not only supports but significantly augments human decision-making processes.

This work explores the potential of Visual Programming Languages (VPLs) and no-code platforms to foster participation among users with limited computing experience in the design of ML-based systems. Conducting expert-based testing of the PyFlowML prototype, our preliminary research focuses on developing trustworthy ML-based prototypes that provide Explainable AI (XAI) techniques. Our evaluation employs heuristic methods and direct interactions with experts using the prototype. Utilizing cognitive walkthroughs with a think-aloud protocol, along with quantitative assessments such as task completion time and the System Usability Scale (SUS), our findings highlight the need of streamlining ML processes to enhance broader participation. These insights lay the groundwork for future research aimed at making the design of ML-based systems more accessible and collaborative through VPL-based tools.

In the era of ubiquitous Artificial Intelligence (AI), Machine Learning (ML) systems have emerged as pivotal in advancing societal progress. Yet, their complexity often requires the expertise of professionals, presenting an entry barrier for less-experienced computing practitioners. In the realm of Human-Centered AI (HCAI), ongoing research is developing new approaches to engage users via intuitive interfaces in the design of ML-based systems. For example, Visual Programming Languages (VPLs) and no-code platforms offer user-friendly experiences by avoiding complex computational operations. However, literature on VPL-based tools for novices reveals a gap: many tools offer limited interpretability approaches or are overly complex for easy customization. To address this gap, we developed the PyFlowML prototype, an open-source, flow-based programming tool with a focus on Explainable AI (XAI). This study aims to set a benchmark in the field by comparing PyFlowML with KNIME, a similar tool known for its usability among domain specialists. Our results show that domain specialists perceive flow-based language tools as valuable. This study highlights the potential of VPL-based tools to make the design of trustworthy ML-based systems more inclusive, thereby contributing to the advancement of AI democratization.

The ongoing digital revolution in the healthcare sector, emphasized by bodies like the US Food and Drug Administration (FDA), is paving the way for a shift towards person-centric healthcare models. These models consider individual needs, turning patients from passive recipients to active participants. A key factor in this shift is Artificial Intelligence (AI), which has the capacity to revolutionize healthcare delivery due to its ability to personalize it. With the rise of software in healthcare and the proliferation of the Internet of Things (IoT), a surge of digital data is being produced. This data, alongside improvements in AI's explainability, is facilitating the spread of person-centric healthcare models, aiming at improving health management and patient experience. This paper outlines a human-centered methodology for the development of an AI-as-a-service platform with the goal of broadening access to personalized healthcare. This approach places humans at its core, aiming to augment, not replace, human capabilities and integrate in current processes. The primary research question guiding this study is: "How can Human-Centered AI principles be considered when designing an AI-as-a-service platform that democratizes access to personalized healthcare?" This informed both our research direction and investigation. Our approach involves a design fiction methodology, engaging clinicians from different domains to gather their perspectives on how AI can meet their needs by envisioning potential future scenarios and addressing possible ethical and social challenges. Additionally, we incorporate Meta-Design principles, investigating opportunities for users to modify the AI system based on their experiences. This promotes a platform that evolves with the user and considers many different perspectives.

Abstract The proliferation of sensors and smart Internet of Things (IoT) devices in our everyday environments is reshaping our interactions with everyday objects. This change underlines the need to empower non-expert users to easily configure the behaviour of these devices to align with their preferences and habits. At the same time, recent advances in generative transformers, such as ChatGPT, have opened up new possibilities in a variety of natural language processing tasks, enhancing reasoning capabilities and conversational interactions. This paper presents RuleBot + + , a conversational agent that exploits GPT-4 to assist the user in the creation and modification of trigger-action automations through natural language. After an introduction to motivations and related work, we present the design and implementation of RuleBot + + and report the results of the user test in which users interacted with our solution and Home Assistant, one of the most used open-source tools for managing smart environments.

In the last few years, text and voice-based conversational agents have become more and more popular all over the world as virtual assistants for a variety of tasks. In addition, the deployment on the market of many smart objects connected with these agents has introduced the possibility of controlling and personalising the behaviour of several connected objects using natural language. This has the potential to allow people, also those without a technical background, to effectively control and use the wide variety of connected objects and services. In this paper, we present an analysis of how conversational agents have been used to interact with smart environments (such as smart homes). For this purpose, we have carried out a systematic literature review considering publications selected from the ACM and IEEE digital libraries to investigate the technologies used to design and develop conversational agents for IoT settings, including Artificial Intelligence techniques, the purpose that they have been used for, and the level of user involvement in such studies. The resulting analysis is useful to better understand how this field is evolving and indicate the challenges still open in this area that should be addressed in future research work to allow people to completely benefit from this type of solution.

This contribution presents ModeLLer, a prototype of a web tool for system modelling based on a block-based visual editor. The aim of ModeLLer is to enable collaborative environments in requirements elicitation, allowing end-users to create UML class diagrams without any knowledge of the (semi-)formal UML notation.

Abstract Chatbot-based tools are becoming pervasive in multiple domains from commercial websites to rehabilitation applications. Only recently, an eleven-item satisfaction inventory was developed (the ChatBot Usability Scale, BUS-11) to help designers in the assessment process of their systems. The BUS-11 has been validated in multiple contexts and languages, i.e., English, German, Dutch, and Spanish. This scale forms a solid platform enabling designers to rapidly assess chatbots both during and after the design process. The present work aims to adapt and validate the BUS-11 inventory in Italian. A total of 1360 questionnaires were collected which related to a total of 10 Italian chatbot-based systems using the BUS-11 inventory and also using the lite version of the Usability Metrics for User eXperience for convergent validity purposes. The Italian version of the BUS-11 was adapted in terms of the wording of one item, and a Multi-Group Confirmatory Factorial Analysis was performed to establish the factorial structure of the scale and compare the effects of the wording adaptation. Results indicate that the adapted Italian version of the scale matches the expected factorial structure of the original scale. The Italian BUS-11 is highly reliable (Cronbach alpha: 0.921), and it correlates to other measures of satisfaction (e.g., UMUX-Lite, τb = 0.67; p < .001) by also offering specific insights regarding the chatbots’ characteristics. The Italian BUS-11 can be confidently used by chatbot designers to assess the satisfaction of their users during formative or summative tests.

Abstract The Bot Usability Scale (BUS) is a standardised tool to assess and compare the satisfaction of users after interacting with chatbots to support the development of usable conversational systems. The English version of the 15-item BUS scale (BUS-15) was the result of an exploratory factorial analysis; a confirmatory factorial analysis tests the replicability of the initial model and further explores the properties of the scale aiming to optimise this tool seeking for the stability of the original model, the potential reduction of items, and testing multiple language versions of the scale. BUS-15 and the usability metrics for user experience (UMUX-LITE), used here for convergent validity purposes, were translated from English to Spanish, German, and Dutch. A total of 1292 questionnaires were completed in multiple languages; these were collected from 209 participants interacting with an overall pool of 26 chatbots. BUS-15 was acceptably reliable; however, a shorter and more reliable solution with 11 items (BUS-11) emerged from the data. The satisfaction ratings obtained with the translated version of BUS-11 were not significantly different from the original version in English, suggesting that the BUS-11 could be used in multiple languages. The results also suggested that the age of participants seems to affect the evaluation when using the scale, with older participants significantly rating the chatbots as less satisfactory, when compared to younger participants. In line with the expectations, based on reliability, BUS-11 positively correlates with UMUX-LITE scale. The new version of the scale (BUS-11) aims to facilitate the evaluation with chatbots, and its diffusion could help practitioners to compare the performances and benchmark chatbots during the product assessment stage. This tool could be a way to harmonise and enable comparability in the field of human and conversational agent interaction.

Abstract Standardised tools to assess a user’s satisfaction with the experience of using chatbots and conversational agents are currently unavailable. This work describes four studies, including a systematic literature review, with an overall sample of 141 participants in the survey (experts and novices), focus group sessions and testing of chatbots to (i) define attributes to assess the quality of interaction with chatbots and (ii) the designing and piloting a new scale to measure satisfaction after the experience with chatbots. Two instruments were developed: (i) A diagnostic tool in the form of a checklist (BOT-Check). This tool is a development of previous works which can be used reliably to check the quality of a chatbots experience in line with commonplace principles. (ii) A 15-item questionnaire (BOT Usability Scale, BUS-15) with estimated reliability between .76 and .87 distributed in five factors. BUS-15 strongly correlates with UMUX-LITE by enabling designers to consider a broader range of aspects usually not considered in satisfaction tools for non-conversational agents, e.g. conversational efficiency and accessibility, quality of the chatbot’s functionality and so on. Despite the convincing psychometric properties, BUS-15 requires further testing and validation. Designers can use it as a tool to assess products, thus building independent databases for future evaluation of its reliability, validity and sensitivity.

Abstract During the last decade, touchless gestural interfaces have been widely studied as one of the most promising interaction paradigms in the context of pervasive displays. In particular, avatars and silhouettes have proved to be effective in making the touchless capacity of displays self-evident. In this paper, we focus on a child–display interaction approach to avatar-based touchless gestural interfaces. We believe that large displays offer an opportunity to stimulate children’s experiences and engagement; for instance, learning about art is very engaging for children but can bring a number of challenges. Our study aims to contribute to the literature on both pervasive displays and child–computer interaction by reporting the results of a study involving 107 children aged 2 to 10 years. The main purposes of this study were to discover: (1) whether an avatar (movable or immovable) provides interactions that are intuitive for children and therefore help to overcome so-called “affordance blindness”; (2) whether an avatar-based touchless interface makes children’s experiences engaging and enjoyable therefore improving recall of content provided through the interaction (learning about art). The study unveiled relevant outcomes in terms of affordance blindness and two-handed interactions. We provide evidence indicating that chronological age influences the style of child–avatar interaction. Finally, it is suggested that avatars could facilitate the development of new effective educational technologies for young children.

Software developers cannot easily anticipate future, idiosyncratic needs of end-users that are not always known at the time software is designed and developed, but rather emerge during the use of s...

Smart Interactive Experiences (SIEs) are usage situations enabled by the Internet of Things that empower users to interact with the surrounding environment. The goal of our research is to define methodologies and software environments to support the design of SIEs; more specifically, we focus on design paradigms suitable for experts of given domains, who however might not be experts in technology. In this context, this paper discusses some trade-offs that we identified between six different dimensions that characterise the quality of software environments for SIE design. The trade-offs emerged from the analysis of data collected in an experimental study that compared three different design paradigms to understand in which measure each paradigm supports the creative process for SIE design. After reporting on the study procedure and the data analyses, the paper illustrates how the resulting trade-offs led us to identify alternatives for SIE design paradigms, and to structure on their basis a modular architecture of a software platform where the strengths of the three paradigms can be exploited flexibly, i.e. depending on the constraints and the requirements characterising specific design situations.

Abstract Automation in computing systems has always been considered a valuable solution to unburden the user. Internet of Things (IoT) technology best suits automation in different domains, such as home automation, retail, industry, and transportation, to name but a few. While these domains are strongly characterized by implicit user interaction, more recently, automation has been adopted also for the provision of interactive and immersive experiences that actively involve the users. IoT technology thus becomes the key for Smart Interactive Experiences (SIEs), i.e., immersive automated experiences created by orchestrating different devices to enable smart environments to fluidly react to the final users’ behavior. There are domains, e.g., cultural heritage, where these systems and the SIEs can support and provide several benefits. However, experts of such domains, while intrigued by the opportunity to induce SIEs, are facing tough challenges in their everyday work activities when they are required to automate and orchestrate IoT devices without the necessary coding skills. This paper presents a design approach that tries to overcome these difficulties thanks to the adoption of ontologies for defining Event-Condition-Action rules. More specifically, the approach enables domain experts to identify and specify properties of IoT devices through a user-defined semantics that, being closer to the domain experts’ background, facilitates them in automating the IoT devices behavior. We also present a study comparing three different interaction paradigms conceived to support the specification of user-defined semantics through a “transparent” use of ontologies. Based on the results of this study, we work out some lessons learned on how the proposed paradigms help domain experts express their semantics, which in turn facilitates the creation of interactive applications enabling SIEs.

Students in higher education are traditionally requested to produce various pieces of written work during the courses they undertake. When students' work is submitted online as a whole, both the ethically questionable act of procrastinating and late submissions affect performance. The objective of this paper is to assess the performance of students from a control group, with that of students from an experimental group. The control group produced work as a unique deliverable to be submitted at the end of the course. On the other hand, the experimental group worked on each part for a week, and their work was managed by a wiki environment and monitored by a specifically developed software. Positive effects were noticed in the experimental group, as both students' time management skills and performance increased. Replications of this experiment can and should be performed, in order to compare results in coursework submission.

A recent contribution to the ongoing debate concerning the concept of usability and its measures proposed that usability reached a dead end – i.e. a construct unable to provide stable results and to unify scientific knowledge. Extensive commentaries rejected the conclusion that researchers need to look for alternative constructs to measure the quality of interaction. Nevertheless, several practitioners involved in this international debate asked for a constructive way to move forward the usability practice. In fact, two key issues of the usability field were identified in this debate: (i) knowledge fragmentation in the scientific community, and (ii) the unstable relationship among the usability metrics. We recognise both the importance and impact of these key issues, although, in line with others, we may not agree with the conclusion that the usability is a dead end. Under the light of the international debate, this work discusses the strengths and weaknesses of usability construct and its application. Our discussion focuses on identifying alternative explanations to the issues and to suggest mitigation strategies, which may be considered the starting point to move forward the usability field. However, scientific community actions will be needed to implement these mitigation strategies and to harmonise the usability practice.

Algorithms are more and more pervading our everyday life: from automatic checkouts in supermarkets and e-banking to booking a flight online. Understanding an algorithmic solution to a problem is a very relevant activity to improve end-users’ involvement. To this end, adopting a meta-design approach may help to support end-users to appropriate the design skills necessary for contributing to system design, in new and engaging modalities. By acquiring Computational Thinking (CT) skills (e.g., algorithmic thinking, abstraction), end-users will be able to understand and trust algorithms, while at the same time participate in the design and development of systems evolving in accordance with their needs. In this work, we focus on two different ways of improving CT skills: playfulness and collaboration. We introduce a game-based system, TAPASPlay, to foster CT skills and we report the results of an exploratory study with 18 users; our hypothesis is that learning CT through gameplay is effective and we tested it by involving participants in game sessions providing playful experience and collaborative learning.

In recent years, smart objects are increasingly pervading the environments we live in. For HCI researchers, an important challenge is how non-technical users can establish the behavior of such devices. This poster presents a new technology implementing a tangible-programming paradigm, which allows non-programmers to synchronize the behavior of ecologies of smart objects, thus determining the creation and customization of smart environments.

In this paper we describe how to use a Game-Based Learning (GBL) approach to help end-user programmers to develop Computational Thinking (CT) skills. CT represents a framework consisting of a set of skills such as: abstraction, decomposition and more in general problem solving expressed in a computational form (algorithmic thinking) that can be easily formalised into a computer program. Those skills are beneficial for end-user programmers in order to model a task for being tackled with computational tools, e.g. spreadsheets, domain specific and visual languages. TAPASPlay is an engaging GBL platform designed to help end-user to learn algorithmic thinking.

While educational technology has a long pedigree, the last few years have seen dramatic changes. These have included the rise and institutionalisation of MOOCs, and other web-based initiatives such as Kahn Academy and Peer-to-Peer University (P2PU). Classrooms have also been transformed with growing use of mobile devices and forms of flipped classroom; and educational progress and engagement has been increasingly measured leading to institutional and individual learning analytics. This workshop seeks to understand the interaction of these issues with human--computer interaction in a number of ways. First to ask what HCI has to contribute to these in terms of the design of authoring and learning platforms, and the wider socio-political implications of increasingly metric-driven governance? Second to discuss how will these changes affect HCI education? Together practice-based and theoretical approaches will help us build a clear understanding of the current state and future challenges for educational technology and HCI.

Public displays have lately become ubiquitous thanks to the decreasing cost of such technology and public policies supporting the development of smart cities. Depending on form factor, those displays might use touchless gestural interfaces that therefore are becoming more often the subject of public and private research. In this paper, we focus on touchless interactions with situated public displays, and introduce a pilot study on comparing two interfaces: an interface based on the Microsoft Human Interface Guidelines (HIG), a de facto standard in the field, and a novel interface, designed by us. Differently from the HIG-based one, our interface displays an avatar, which does not require any activation gestures to trigger actions. Our aim is to study how the two interfaces address the so-called interaction blindness --- the inability of the users to recognize the interactive capabilities of those displays. According to our pilot study, although providing a different approach, both interfaces has proven effective in the proposed scenario: a public display in a hall inside a University campus building.

Computational Thinking has recently returned into the limelight as an essential skill to have for both the general public and disciplines outside Computer Science. It encapsulates those thinking skills integral to solving complex problems using a computer, thus widely applicable in our technological society. Several public initiatives such as the Hour of Code successfully introduced it to millions of people of different ages and backgrounds, mostly using Blocks Programming Environments like Scratch that lower the barriers of programming and facilitate learning. In this paper we present our arguments for fostering Computational Thinking skills using a Blocks Programming Environment augmented with a Tangible User Interface, namely by exploiting objects whose interactions with the physical environment are mapped to digital actions performed on the system. Our demonstration includes a working prototype implementing our Tangible Blocks Programming Environment called TAPAS.

Nowadays we are continuously surrounded by new digital systems featuring easy to use and engaging interaction modalities, such as multi-touch, gesture, tangible, or voice interaction. The enriched and natural experience provided by this new paradigm - known as Natural User Interface - has promoted its adoption in many ubiquitous contexts due to its effectiveness in dealing with a wide audience of mostly inexperienced users; Pervasive Displays, namely variously-sized displays ecosystems supporting simultaneous interactions with public screens naturally use those new paradigms. Nonetheless, if we want these systems to stay out in public spaces for long periods of time, they must provide users with an easy way of being adapted to their heterogeneous usage contexts. In this paper, we propose an End- User Programming approach to this problem introducing TAPAS, a system that combines a tangible interaction with a puzzle metaphor, allowing users to create workflows on a Pervasive Display to satisfy their needs; we also carried out a preliminary evaluation of our system with second year university students and interaction designers, gathering useful feedback to improve TAPAS and employ it in many other domains.

With technology changing the nature of the driving task, qualitative methods can help designers understand and measure driver-car interaction naturalness. Fifteen drivers were interviewed at length in their own parked cars using ethnographically-inspired questions probing issues of interaction salience, expectation, feelings, desires and meanings. Thematic analysis and content analysis found five distinct components relating to 'rich physical' aspects of natural feeling interaction typified by richer physical, analogue, tactile styles of interaction and control. Further components relate to humanlike, intelligent, assistive, socially-aware 'perceived behaviours' of the car. The advantages and challenges of a naturalness-based approach are discussed and ten cognitive component constructs of driver-car naturalness are proposed. These may eventually be applied as a checklist in automotive interaction design.

This paper discusses the design, development and deployment of a large projected multi-touch surface within a rural context. Based on our previous work we deployed the system and worked in a real world setting in order to understand how it might be used in this particular scenario and to further understand the issues involved in using such systems in a rural context. Such systems are often deployed in urban or lab-based scenarios, however rural settings come with their own set of issues that can often make them very different in terms of design implications from urban settings, and it is important to understand how these issues can impact upon both the design of the interface and the whole system. This innovative research engaged with the local community and this enabled us to further understand how we might advance the use of the system, in terms of its interface, software architecture and physical design. This paper discusses the impetus for the design of the system, the methods we used to frame our studies, the technical development and design of the system, and some findings from the actual deployment.

This Studio will involve participants creating interactions with physical and digital elements. They will have the opportunity to use a toolkit we developed that combines physical and digital widgets into a unique environment to allow the rapid setup of device ecologies. Therefore, participants will be able to explore how the toolkit support to physical/digital interaction gives people with low, when no, technical skills the possibility to rapidly prototype interactions among heterogeneous devices, thus blurring the boundaries between the physical and the digital world.

During and after crisis situations people are interested in getting knowledge about what happened and in obtaining information regarding damages, victims, and possible repercussions. Social network systems represent powerful sources due to their rapid growth in the last few years and the amount of continuous updated information published by people. Studies confirmed that people are interested in reporting facts during hazards, however due to the wide distribution of information and the lack of mechanisms to re-use it, it is an awkward task to be accomplished. For the above reasons in this paper we present SocialStory, a social platform for helping people to retrieve and filter materials available on the Internet and to compose and share personal experiences about crisis situations.

Third generation devices, such as smartphones, have the possibility of knowing the position of the user. By combining time, position and data in the Cloud it is possible to make smart deductions as to what information the user needs. These deductions can be performed by an automated assistant that have access to the user's e-mail and SMS messages, calendar, phone book, notes, etc., as well as to the position of the user. The assistant can present the information in an "I feel lucky" display on the user's smartphone. These concepts have been evaluated in a case study with a group of students, simulating the output of such an interface.

Visualization of set-valued attributes in multi-dimensional information visualization systems remains a relatively unexplored problem. Here we introduce a novel method for visualizing set-valued attributes that we call the singleton set distribution view and integrate it into an interactive multi-dimensional attribute visualization tool utilizing parallel bargrams (aka equal-height histograms) as its main visual motif. We discuss our design rationale and report on the results of an evaluation study.

Touchless interaction techniques do not require physical contact while interacting with a system so to allow natural interaction with digital information, made tangible in the physical world through pervasive screen displays. In this project we explore the use of Nintendo Wii Remote controller as a touchless interface for interacting with map based applications in large displays environments. A prototype (Don't Touch Me) was developed that allows users to collaborative place multimodal annotations on a map: pictorials, auditives and haptics.

Pattern languages might be useful tools for design as far as designers can identify the right patterns. For this users need to understand the relationships between patterns and how to combine them. In this process, knowing how patterns have been used by other designers might help in identifying the best combination of solutions. In this paper we propose a module that recommends patterns based on the selection already made by them, with a view to supporting designers in making the correct design decisions.

In this work we present a system to encode location based information extracted from a media collection (the Flickr tagging system) into a single 2D physical label. This information is clustered by using locations metadata (geotags) and key-words (tags) associated to pictures. Our system helps two types of users: the user authoring the physical label and the final user who retrieves up-to-date information scanning the label with his/her camera phone. Preliminary results for a given seed word (the tag Napoli) on 3000 photographs are presented, together with some ad-hoc weighting factors that help in finding significant pictures (representing places) that can be associated to a specific area.

Specifying the access policy of a Web system is a relevant design concern that is often dismissed or postponed until the implementation. ADM-RBAC (Ariadne development method with role-based access control) is a model-driven approach for Web systems that supports the specification of access control policies in an integrated way and at two abstraction levels. At the conceptual level a number of visual models specify the access policy in a way that is similar to the userspsila point of view. At the detailed level, models are oriented towards providing enough details to generate prototypes in an automatic or semiautomatic way. In this paper we describe the visual models of ADM-RBAC and their empirical evaluation.

Current research in interaction aims at defining new types of multimedia and multimodal experience, at enriching everyday objects and environments with the ability to capture user actions and intentions, and at integrating real and virtual sources of information, typically exploiting the visual channel. These forms of interaction usually require dedicated architectures, often relying on different component models, and with rigid types of configuration. We present an approach to the integration of real and virtual world sensors and effectors, and of traditional multimedia environments within a single component-based architecture. Environments in this architecture are defined as networks of plugins, each equipped with computational, presentation and communication capabilities. Examples of integrated environments produceable with this architecture are given.

In this paper we present a distributed videosurveillance framework. Our end is the remote monitoring of the behavior of people moving in a scene exploiting a virtual reconstruction on low capabilities devices, like PDAs and cell phones. The main novelty of this system is the effective integration of the computer vision and computer graphics modules. The first, using a probabilistic frameworks, can detect the position, the trajectory and the posture of peoples moving in the scene. The second exploits the new possibility of both standard 3D graphics libraries on mobile (namely JSR184 and M3G graphic format) and new PDAs processing capability in order to reconstruct the remote surveillance data in real-time.

Today, business to consumer applications have been implemented by building front ends to the old legacy systems. In this paper we question if this is enough? Many customers going to the Web to make a booking may be flexible with regard to dates and times, where to go and even if to go. The interfaces that are offered today expect detailed and specific data and do therefore not account for this flexibility. In this paper we discuss the possibilities of retaining some of this functionality offered by the human travel agent by enhancing current Web interfaces. After presenting a background study, we will suggest interfaces that to a better degree can aid the customer in performing a booking. While we use booking as an example, many of the ideas presented here can be applied to other systems as well.

The decreasing cost and the increasing availability of new technologies is enabling people to create their own digital libraries. One of the main topics in personal digital libraries is allowing people to select interesting information among all the different digital formats available today (pdf, html, tif etc.). Moreover the increasing availability of these on-line libraries, as well as the advent of the so-called semantic Web (Berners-Lee, 1999), is raising the demand for converting paper documents into digital, possibly semantically annotated, documents. These motivations drove us to design a new system which could enable the user to interact and query documents independently from the digital formats in which they are represented. In order to achieve this independence from the format, we consider all the digital documents contained in a digital library as images. Our system tries to automatically detect the layout of the digital documents and recognize the geometric regions of interest. All the extracted information is then encoded with respect to a reference ontology, so that the user can query his digital library by typing free text or browsing the ontology. This approach could help users, because they don't need to know SQL since they could only recall visual hints about a document: like find me a document with a picture on the left side and a big title centered on top of the page