AbstractÐWhile task modeling and task-based design are entering into current practice in the design of interactive software applications, there is still a lack of tools supporting the development and analysis of task models. Such tools should provide developers with ways to represent tasks, including their attributes and objects and their temporal and semantic relationships, to easily create, analyze, and modify such representations and to simulate their dynamic behavior. In this paper, we present a tool, CTTE, that provides thorough support for developing and analyzing task models of cooperative applications, which can then be used to improve the design and evaluation of interactive software applications. We discuss how we have designed this environment and report on trials of its use.Index TermsÐTask models, models for interactive software systems, automatic tools for human-computer interaction, user interfaces.

Abstract-The increasing availability of new types of interaction platforms raises a number of issues for designers and developers. There is a need for new methods and tools to support development of nomadic applications, which can be accessed through a variety of devices. This paper presents a solution, based on the use of three levels of abstractions, that allows designers to focus on the relevant logical aspects and avoid dealing with a plethora of low-level details. We have defined a number of transformations able to obtain user interfaces from such abstractions, taking into account the available platforms and their interaction modalities while preserving usability. The transformations are supported by an authoring tool, TERESA, which provides designers and developers with various levels of automatic support and several possibilities for tailoring such transformations to their needs.Index Terms-Design tools and techniques, user interfaces, heterogeneous clients, multiplatform user interfaces, authoring environments, abstract user interfaces, user interface design, task models.

Our life is characterized by the presence of a multitude of interactive devices and smart objects exploited for disparate goals in different contexts of use. Thus, it is impossible for application developers to predict at design time the devices and objects users will exploit, how they will be arranged, and in which situations and for which objectives they will be used. For such reasons, it is important to make end users able to easily and autonomously personalize the behaviour of their Internet of Things applications, so that they can better comply with their specific expectations. In this paper, we present a method and a set of tools that allow end users without programming experience to customize the context-dependent behaviour of their Web applications through the specification of trigger-action rules. The environment is able to support end-user specification of more flexible behaviour than what can be done with existing commercial tools, and it also includes an underlying infrastructure able to detect the possible contextual changes in order to achieve the desired behaviour. The resulting set of tools is able to support the dynamic creation and execution of personalized application versions more suitable for users’ needs in specific contexts of use. Thus, it represents a contribution to obtaining low threshold/high ceiling environments. We also report on an example application in the home automation domain, and a user study that has provided useful positive feedback.