John Darzentas

Evaluating usability evaluation methods: criteria, method and a case study

The paper proposes an approach to comparative usability evaluation that incorporates important relevant criteria identified in previous work. It applies the proposed approach to a case study of a comparative evaluation of an academic website employing four widely-used usability evaluation methods (UEMs): heuristic evaluation, cognitive walkthroughs, think-aloud protocol and co-discovery learning.

Simulation of road traffic conflicts at T-junctions

This paper describes an event-stepping (discrete- event) simulation model of a nonurban T-junction. The model is intended for investigating the risk of traffic accidents at such junctions, using a version of the traffic-conflict technique. The model uses empirical data and predicts the number and severity of conflicts as a function of various traffic and behavioural parameters. Some applications of the model are outlined. The traffic-handling capacity of the junction and delays at it are not considered.

Intention modelling: approximating computer user intentions for detection and prediction of intrusions

This paper introduces and describes an innovative modelling approach which utilises models that are synthesised through approximate calculations of user actions and extensive representation of knowledge about how to perform these actions. The Intention modelling approach is based on theories of cognitive and task modelling as well as on theories of intention, rational action and plan recognition. Intention Models (IMs) have been used in the detection of malicious attacks which usually do not consist of illegal actions, but of a set of actions individually acceptable to the system which at a higher level may form non acceptable task(s). A first effort at implementing these models for a real application was for the creation of the UII system, a research prototype for the detection of anomalous behaviour of network users obtained by reasoning about the characterisation of their intentions. It was developed as an autonomous module within SECURENET, a European funded programme that aims at defending open computer systems, employing advanced techniques and methodologies.

Major HCI challenges for open source software adoption and development

The aim of the paper is to identify and discuss major challenges for OSS from an HCI perspective, so as to aid the adoption and development processes for end-users, developers and organizations. The paper focuses on four important HCI concerns: product usability, support for user and development communities, accessibility and software usability and proposes areas for further research on the basis of related work and own experiences.

A descriptive reference framework for the personalisation of e-business applications

Personalisation is widely considered as a critical element of contemporary electronic businesses. However, despite the wealth of scientific work on personalisation, the definition of the term remains blurred with as consequence a lack of clarity as to what to design or evaluate when it comes to this area of an e-business. E-business stakeholders, including designers, managers and customers, need to understand the significance of personalisation features for many reasons including: guidance for design and evaluation, user appeal and implications for e-business functionality. The paper introduces a descriptive framework for personalisation aspects of e-businesses, in business-to-consumer (B2C) situations, that is related to typical e-business functionality. The proposed framework classifies previous research and extends it to provide e-commerce stakeholders with a vocabulary for analysing e-businesses, for comparing personalisation features, and for explaining e-business commerce evaluation results. The framework is applied to the evaluation of the personalisation features of contemporary clothing e-businesses, and conclusions are drawn for the readiness of this sector to adopt personalisation requirements.

Cybernetic embodiment and the role of autonomy in the design process

Purpose – This paper aims to develop the role of autonomy in the emergence of the design process. It shows how the design process is facilitated by autonomy, how autonomy is enhanced through the design process and how the emergence of anticipatory and future‐oriented representational content in an autonomous cognitive system provides the functionality needed for the strengthening of both its autonomy and the design process, in which the autonomous cognitive system purposefully engages.Design/methodology/approach – Initially, the essential characteristics of the design process and of the cognitive systems participating in it will be identified. Then, an attempt to demonstrate the ability of an enhanced second‐order cybernetic framework to satisfy these characteristics will be made. Next, an analytic description of the design process under this framework is presented and the respective implications are critically discussed.Findings – The role of autonomy is crucial for the design process, as it seems that a...

Facilitating user-system interaction: the GAIA interaction agent

This paper presents the identification, design and implementation of a user interface to a brokerage system and the conceptual architecture and functional behaviour of an intelligent interaction agent that supports and enhances the interaction between the user and the system. The term interaction agent is used in order to describe a particular class of interface agents that function as intelligent personal assistants to users of a computer based system. The interaction agent provides assistance to the user in two contexts. On the user interface level it assists users to comprehend and manipulate the user interface. On the domain of application level, it provides users with information and advice according to their preferences. This work is being carried out in the context of an ACTS (AC 221) project GAIA (Generic Architecture for Information Availability).

Virtual environments for collaborative design: requirements and guidelines from a social action perspective

The paper is concerned with the design of virtual environments for collaborative design (VECD) – a particular class of collaborative virtual environments (CVEs) that focus on supporting design activities. VECD are becoming essential collaboration platforms for many designers and their clients, in a wide range of design domains including product, interior, architectural, automotive design, etc. However, the contemporary design considerations of VECD are mainly driven by systematic approaches that do not reflect upon knowledge regarding requirements that stem out of everyday collaborative design activities. A consequence is that they do not yield methodical guidance to designers of VECD applications. This paper takes a social action standpoint for the purposeful identification and organisation of collaborative design activities; proposes guidelines at multiple levels of abstraction for the design of VECD; and, finally, applies these to a case study development of a specific VECD for interior space design. The paper provides practical aids to designers of VECD so that they incorporate requirements about collaborative design early in the development lifecycle.

Research: Model for network behaviour under viral attack

Computer viruses, worms and Trojan horses pose the most severe intrusion threat against an automated environment, especially if this environment is distributed and the ability to enforce physical access control is very limited. These structures are also collectively referred to as malicious software. In this paper, a model for viral attacks against computer networks is being developed. The soundness of the model is being tested via simulation experiments. Interesting results that can be practically useful to network administrators are being derived.

End user tools for ambient intelligence environments: an overview

New elements that are introduced by the nature of living and interacting within an Ambient Intelligence (AmI) environment lead to new HCI paradigms. While AmI User Interfaces are moving off the desktop and the GUI paradigm, and become augmented and diffused within the ubiquitous environments, a new generation of User Interface Design Tools to facilitate the design and realization of AmI applications, is emerging. Issues and specific shifts related to Human Computer Interaction in AmI environments, which affect the design of these tools, is outlined in this paper. The high level characteristics of End User Tools that facilitate users to reason as well as manipulate the behavior of the AmI environment are outlined.