Dimitris Nathanael

Cognitive engineering practice: melting theory into reality

Given the growing scope of cognitive engineering, our intent in this paper is to help uncover some of the regularities of the discipline. Adopting a pragmatic view, we attempt to interpret what cognitive engineers really do in practice, and to partly systematize this reality. The paper stresses the need for: (i) an explicit consideration of the demand for intervention and the analysts preconceptions during the framing of the world-to-study, (ii) the adoption of multiple views for a sufficient understanding of the analysed world, (iii) a continuous reframing of the system under consideration (i.e., topological boundaries as well as timeframes) as the understanding of reality unfolds, (iv) acceptance and exploitation of the dialectic process between analysis/understanding and design/prediction.

On the development of work practices: a constructivist model

The present paper aims to present a model for the development and evolution of work practices. Work practices are understood as the more or less stable, historically developed and partially unacknowledged arrays of activity, which are at the basis of successful action in a particular work setting. From a methodological perspective, work practices correspond to a level of analysis that is more macroscopic than the level of individual situated activity. The practice level of analysis considers explicitly both development in time plus the collective aspect. The proposed model is inspired by two distinct sources: applied research in cognitive engineering and anthropology; and theoretical work in the social sciences. It contends that practices can be seen as evolving entities that emerge through repetition, engaged situated distinction and subsequent descriptions. Descriptions are supposed to re-enter in the day-to-day conduct as formalisations institutionalising and/or rearranging practice on the way. It is argued that the model can be useful in order to gain insight and steer the process of cognition–organisation–technology co-adaptation (i.e. the development of practice) that follows technological or organisational changes.

A pragmatic mapping of factors behind deviating acts in aircraft maintenance

Abstract In this paper, we analyze twelve cases of deviations from prescribed procedures during scheduled/unscheduled maintenance checks, carried out by an aircraft maintenance organization in Greece. The detailed analysis of these cases let us identify specific factors that guided maintenance technicians towards alternative courses of action. Our focus is not on the material etiology of deviations but on the underlying factors that determined the actual decision action path by the air maintenance technicians. A generalization of factors is then being made, out of the specific factors identified for each case. The factors identified ranged from the most normative (e.g. manuals) to the most contextual ones (e.g. personal comfort, schedule pressures). We suggest that by making generalizations of specific factors identified from a pool of specific cases, we gain intimate knowledge on the cognitive and organizational basis of deviations. The intimate knowledge of the etiology of deviations may help us advance towards a resilient safety management in aircraft maintenance; one that goes beyond the striving for compliance, a safety management that (i) acknowledges people on the shop floor inevitably make choices and (ii) supports them in taking more “informed” and accountable decisions.

A question of our marketing or our preconceptions: Commentary on the paper ‘A strategy for human factors/ergonomics: developing the discipline and profession’

The present paper is a commentary on the recently published IEA strategy for human factors/ergonomics (Dul, J., et al. (2012), A strategy for human factors/ergonomics: developing the discipline and profession. Ergonomics, 55(4), 377–395). Two main issues that demand attention are: (i) the way others understand our profession and discipline, and (ii) the way we understand our profession and added value to industry. First, it is advocated that the discussion on the future of human factors/ergonomics (HFE) should be focused more on the quality of the delivered value of HFE and less on its visibility and marketing. Second, the three fundamental characteristics of HFE, as proposed in the report, are discussed and the consequences of this proposal are further developed. Arguments are put forward on the endemic epistemological vagueness within the discipline and on the optimistic definition of its aim. Finally, a proposal is made at the epistemological level, which challenges some established convictions of the discipline. It is advocated that such an epistemological evolution may be necessary if HFE is to make progress towards contributing to system performance. Practitioner Summary: The paper is a commentary on the IEA strategy for human factors/ergonomics. Issues discussed are, the way others understand our profession and the way we understand our profession and added value to industry. Some of the established convictions of the discipline are challenged and proposals are made to overcome these.

The effects of changes in the traffic scene during overtaking

Overtaking maneuvers were studied in real traffic, by comparing cases where a change in the opposite traffic occurred during the overtaking maneuver i.e., appearance of an oncoming car, with cases where no change occurred during the maneuver i.e., either an already apparent oncoming car or no oncoming car. In total 45 naturally occurring cases of overtaking were analysed. By examining the time headways (TH) between the overtaking car and the other cars involved, at the end of the maneuver, a significant correlation was found between the TH to opposite traffic and the TH rear to the overtaken car. In cases where a change in the opposite traffic occurred and the proximity to opposite traffic was below a critical TH (<4s) the appearance of a new-oncoming car caused the overtakers to actively press, both longitudinally and laterally, close to the overtaken car. In cases of overtaking where no change in the opposite traffic occurred, the TH rear to the overtaking vehicle was unaffected by the TH to the opposite traffic. Interestingly, in comparing cases where an oncoming car appeared during overtaking with cases where an oncoming car was apparent from the start of the maneuver both the TH to the opposite traffic and the duration of the maneuver were not found to be significantly different. It is suggested that drivers were probably expecting to be confronted with an oncoming car during the overtaking. However, the decreased available time to disambiguate this situation leads the overtaking driver to limit the rear safety margin of the vehicle being overtaken. The appropriateness of this practice, in terms of safety, remains questionable.

Cognitive task analysis for virtual reality training: the case of CNC tool offsetting

Motivation -- To examine if cognitive task analysis of expert machinists can be effective in developing a virtual reality based training system for CNC tool offsetting. Research approach -- A cognitive task analysis of expert machinists was conducted which informed the development of a VR training system for CNC tool offsetting. Subsequently the effectiveness of the analysis was evaluated by conducting an experiment with 31 mechanical engineering students. Findings/Design -- The virtual reality system demonstrated positive training transfer for the task of tool offsetting. The above indicates that the cognitive task analysis performed was effective in identifying a number of key skills of the tool offsetting task. Research limitations/Implications -- The study does not prove the superiority of cognitive task analysis over other approaches for specifying virtual reality training systems, since it does not compare the cognitively tuned system with another one. Originality/Value -- The present work provides evidence that skill transfer can be achieved even with low physical fidelity provided that the cognitive organization of a task is adequately mapped in the virtual reality system. Take away message -- Further and beyond fidelity issues, cognitive task analysis can provide important input in specifying effective VR training systems.

The “field of safe travel” revisited: interpreting driving behaviour performance through a holistic approach

ABSTRACT The present paper proposes a conceptual framework for the driver’s visual–spatial perceptual processes. Based on a theoretical analysis of driving proposed by Gibson and Crooks [(1938). A theoretical field-analysis of automobile-driving. The American Journal of Psychology, 51, 453–471. doi:10.2307/1416145], the developed field of safe travel (FoST) framework suggests that at any moment the driver constructs a “field” by integrating two perceptual entities: (i) the possible available spatial fields for locomotion and (ii) the driver’s mental image of ego-vehicle outer-line and motion dynamics. This framework is used to reinterpret in a unified way a number of disparate research findings reported in the literature concerning specific driving sub-tasks (e.g. lane keeping and car following). It is argued that the FoST framework may be used to predict drivers’ behaviour in various traffic/situation environments based on their prioritisation between the above two perceptual entities. Implications of the proposed framework at a theoretical and practical level, in view of the future of driving with multiple levels of automation, are also discussed.

User-Centered Design in Practice: A Medical Tele-Consultation Management Application

This paper presents and discusses the design process and the solutions adopted for the development of an information technology system aimed to assist the management of medical tele-consultations. The adopted user-centered design approach, the thorough work analysis carried out at the initial stages of the design process as well as the fact that the ergonomists headed the development team, resulted to a system achieving high usability and acceptance by the users.

Trade-offs among factors shaping operators decision-making: the case of aircraft maintenance technicians

The present research deals with aircraft maintenance technicians (AMTs) situated decision-making in a commercial aircraft maintenance department. The aim is twofold: first, to study how AMTs through their situated decisions experience inconsistencies between diverse organizational imperatives and pragmatic constraints and second, to identify persistent factors, dualities and/or trade-offs that affect these decisions. Towards this end, twenty-five cases where AMTs faced ambiguity or dilemmas and took decisions during maintenance work were analysed, after being observed in situ. The analysis followed a bottom-up approach where the decision cases observed were first examined in terms of the contextual factors that influenced their outcome. Such contextual factors did not only include the random events triggering a need for a decision, but also the pragmatic constraints that were taken into account by AMTs after the triggering event in order to choose an action path. An interpretative analysis of the above decision cases towards a more abstract level of description, the study achieved at identifying a set of persistent factors underlying decisions at the sharp edge of a safety critical system. It is argued that such persistent factors and their articulation can be identified in operators’ decision-making in any particular work setting and can form the basis for sound bottom-up metrics for organizational resilience and proactive safety management.

Detailed design exercises help promote conceptual thinking: Lessons learned from teaching User Centred Design to an engineering class

The present paper deals with a teaching method aiming at overcoming the difficulties of students for conceptual or abstract thinking within a course of User Centred Design. Following the hermeneutic approach a series of small in class exercises have been planned. In those exercises students are urged to brainstorm from early on with all levels of solution representations --even detailed ones--, and then try to elevate these to higher levels of abstraction by questioning them through a peer critique process. The tutor all along that process facilitates several iterations between the conceptual and the detailed design solutions. Our experience has shown that when engaging in the above process, students become more aware of the value of the conceptual design, and are gradually developing a better understanding of it.