Michael Zaki

Pattern Driven Task Model Refinement

Task models have been used as a tool to elicit requirements in the early development stages. Moreover, they have recently proved to be a suitable starting point for modeling of interactive processes. During the different development stages several corresponding task models are built. Although every model is just a refined version from the previous one, this refinement process is not a trivial operation as a lot of rules and restrictions have to be respected in order to successfully infer the suitable task model concerning the current level of abstraction. In this paper we aim to assist the developer by giving him the opportunity to move with a given model from one abstraction level to another one in an easier and more seamless way. Thus, we present an approach consisting of some guideline patterns which help the developer to transform a given task model between the different development stages in a more performing and less error-prone manner.

Towards the Generation of Assistive User Interfaces for Smart Meeting Rooms Based on Activity Patterns

The main purpose of a given smart meeting room is to increase the efficiency of the meetings taking place in this room by assisting the resident actors performing their tasks and thus offering them the opportunity to focus on the exchange of information among each other. However, a proper assistance should be based on a clear understanding of the nature of tasks the users are performing in the environment. Therefore, in this paper we present an attempt to base the design of the assistive system to be operated in smart meeting rooms on activity patterns collected in the analysis stage and resulting from the perception of the human behavior in those environments. The end goal is to tailor individualized user interfaces for each actor depending on his/her current role and user profile.

User-oriented accessibility patterns for smart environments

One of the main indicators concerning the usability of an application is the corresponding level of accessibility provided by this application. Although a lot of work has been done in the software engineering domain, the accessibility problem has not been enough tackled in the HCI area. In this paper we present an idea to resolve the user-related accessibility problems since the modeling stage of smart environment applications while being assisted by patterns. The proposed idea is to provide two generic patterns used for any accessibility modeling problem, and additionally the creation of two pattern libraries presenting concrete solutions for the most common user-based accessibility problems.

Models as a Starting Point of Software Development for Smart Environments

Creating a smart environment is a challenging task because of the excessive software development and adaptation required. Additionally, hardware in form of stationary as well as dynamic devices has to be installed. Similar to traditional software development, evaluating only the end product is often very costly in terms of time and effort needed. This is due to the fact that usually a lot of changes have to take place since the system fails to deliver the expected behaviour. Therefore, modelling is of great benefit. Models help to get a shared and thorough understanding of a specific domain. Making the animation of those models feasible allows getting a first impression of the system under development. Such prototypes of a system can be created on different levels of abstraction. The paper aims to demonstrate how modelling the human behaviour from the perspective of the activities performed in the environment can lead to first abstract prototypes. Those prototypes can be further extended and fostered by device models as well as models for the whole environment. In the paper, we also strive to discuss the costs and benefits of offering an abstract environmental model in 2D or 3D. 3

Special challenges for models and patterns in smart environments

Smart environments aim at inferring the intention of the user and based on that information, they offer optimal assistance for the users while performing their tasks. This paper discusses the role of supportive user interfaces for explicitly interacting with the environment in such cases where implicit interactions of the users fail or the users want to get informed about the state of the environment. It will be shown by small examples how patterns help to specify the intended support with implicit and explicit interactions. A notation for presentation patterns will be introduced that allows users dynamically to change the presentation style. It will be discussed how extended task models can be combined with presentation patterns and how this information can be used in supportive user interfaces on mobile devices.

A methodology for generating an assistive system for smart environments based on contextual activity patterns

Despite the existence of various approaches addressing the development of nowadays interactive systems, smart environments impose an additional set of challenges for the designer. The main tenet of those environments is to deliver proper assistance to resident users who are performing their daily life tasks. However, an assistive system to be deployed in a smart environment has to meet some crucial requirements in order to successfully accomplish its mission. Thus, a well-defined development methodology for the generation of such a system to be employed in a given smart environment is highly beneficial. In this paper, we present a development methodology enabling the generation of tailored (user-specific) assistive user interfaces based on contextual activity patterns. We illustrate step by step the various stages by which the development of a supportive system for smart environments has to pass.

Towards a pattern language for modeling interactive applications in smart meeting rooms

The domain of smart meeting rooms is an interesting emerging subset of pervasive learning environments. In a given smart meeting room, several users are supposed to cooperate together while employing a set of static and dynamic heterogeneous devices beside an ensemble of passive objects. Moreover the location specification for every resident entity in the environment, and the synchronization between the actions to be executed by the various actors have to be taken into account. Thus, the corresponding modeling process of such an environment cannot be considered as a trivial process if we take into account the existing dependencies between all the entities in this environment. In this paper, we present an attempt to overcome the complexity of this process by building a pattern language addressing the domain of smart meeting rooms. We believe that the usage of the patterns included in this pattern language guarantees an effective and less time-consuming modeling process.

On the Suitability of Activity Diagrams and ConcurTaskTrees for Complex Event Modeling

In this paper, we analyze and extend modeling possibilities for complex events in the semiformal business process modeling languages UML activity diagrams and ConcurTaskTrees (CTT). The goal of this paper is to provide an intuitive abstract starting point for complex event specifications in a model-based approach. The resulting models should increase the understandability of the models themselves and the discussion taking place with the developers and the stakeholders. A hierarchy concept for advanced visual event modeling is introduced to activity diagrams. In these models time, data and cardinality aspects can be expressed. A different approach for complex event modeling is proposed using hierarchical task models with CTT. We transform given temporal operators from CTT that are based on process algebra to event algebra. Some extensions for CTT-operators are used to express specific complex event models in a semiformal way.

Integration of patterns into model-based specifications of smart environments

Motivation -- Modeling interactive systems to be employed in smart environments is an overwhelming process for the developer as several surrounding factors have to be taken into account in order to successfully model the tasks to be executed and the environmental constraints associated to those tasks. Therefore, the already existing modeling languages are usually fostered by a tool which guides the developer while constructing her models. However, a lack of concept of reuse on a high level of abstraction can be easily detected. By fetching reusable solutions for reoccurring problems within the models of a given domain, one can accelerate the process of building those models and improve its performance. Thus, the main motivation for our work is to reduce the complexity of designing interactive applications for domains like smart environments by using different kinds of patterns encapsulating best practices for well-known modeling situations. Research approach -- The investigation of one or several suitable modeling languages for smart environments in order to extract useful reusable patterns to be used by the developer. Findings/Design -- We suggested patterns which are able to guide the developer through the different development stages (e.g.: Analysis, Interaction Requirements, Design) and currently we are developing patterns in order to make the models construction process itself easier and less error-prone. Take away message -- The modeling of interactive applications for ubiquitous computing environments (e.g. Smart environments) is a non-trivial process. We suggest overcoming the encountered complexity by taking benefit of the concept of reuse provided by patterns.