Kim J. Vicente

Ecological interface design: theoretical foundations

A theoretical framework for designing interfaces for complex human-machine systems is proposed. The framework, called ecological interface design (EID), is based on the skills, rules, and knowledge taxonomy of cognitive control. The basic goals of EID are not to force processing to a higher level than the demands of the task require, and to support each of the three levels of cognitive control. Thus, an EID interface should not contribute to the difficulty of the task, and at the same time, it should support the entire range of activities that operators will be faced with. Three prescriptive design principles are suggested to achieve this objective, each directed at supporting a particular level of cognitive control. Particular attention is paid to presenting a coherent deductive argument justifying the principles of EID. Support for the EID framework is discussed. Some issues for future research are outlined. >

Ecological Interface Design: Progress and Challenges

Ecological interface design (EID) is a theoretical framework for designing human-computer interfaces for complex sociotechnical systems. Its primary aim is to support knowledge workers in adapting to change and novelty. This literature review shows that in situations requiring problem solving, EID improves performance when compared with current design approaches in industry. EID has been applied to industry-scale problems in a broad variety of application domains (e.g., process control, aviation, computer network management, software engineering, medicine, command and control, and information retrieval) and has consistently led to the identification of new information requirements. An experimental evaluation of EID using a full-fidelity simulator with professional workers has yet to be conducted, although some are planned. Several significant challenges remain as obstacles to the confident use of EID in industry. Promising paths for addressing these outstanding issues are identified. Actual or potential applications of this research include improving the safety and productivity of complex sociotechnical systems.

Coping with human errors through system design: implications for ecological interface design

Research during recent years has revealed that human errors are not stochastic events which can be removed through improved training programs or optimal interface design. Rather, errors tend to reflect either systematic interference between various models, rules, and schemata, or the effects of the adaptive mechanisms involved in learning. In terms of design implications, these findings suggest that reliable human-system interaction will be achieved by designing interfaces which tend to minimize the potential for control interference and support recovery from errors. In other words, the focus should be on control of the effects of errors rather than on the elimination of errors per se. In this paper, we propose a theoretical framework for interface design that attempts to satisfy these objectives. The goal of our framework, called ecological interface design, is to develop a meaningful representation of the process which is not just optimised for one particular level of cognitive control, but that supports all three levels simultaneously. The paper discusses the necessary requirements for a mapping between the process and the combined action/observation surface, and analyses of the resulting influence on both the interferences causing error and on the opportunity for error recovery left to the operator. There has been a rapidly growing interest in the analysis of human error caused by technological development. The growing complexity of technical installations makes it increasingly difficult for operators to understand the system’s internal functions. At the same time, the large scale of operations necessary for competitive production makes the effects of human errors increasingly unacceptable. Naturally enough, human error analysis has become an essential part of systems design. In order to conduct such an analysis, a taxonomy suited to describe human errors is essential. The structure and dimensions of the error taxonomy, however, will depend on the aim of the analysis. Therefore, different categorisations of human errors are useful during the various stages of systems design. At least two different perspectives can be identified, each with its own unique set of requirements. One point of view is useful for predicting the effects of human error on system performance, i.e. a failure-mode-and-effect analysis. For this purpose, a taxonomy based on a model of human error mechanisms should be adopted. A second perspective for error analysis is required for identifying possible improvements in system design. In order to meet the requirements of such an analysis, an error taxonomy based on cognitive control mechanisms (Rasmussen, 1983) is more appropriate. Both types of analyses are essential to system design. The failure-mode-and-effect analysis allows the designer to identify plausible human

There Is More to Monitoring a Nuclear Power Plant than Meets the Eye

A fundamental challenge in studying cognitive systems in context is how to move from the specific work setting studied to a more general understanding of distributed cognitive work and how to support it. We present a series of cognitive field studies that illustrate one response to this challenge. Our focus was on how nuclear power plant (NPP) operators monitor plant state during normal operating conditions. We studied operators at two NPPs with different control room interfaces. We identified strong consistencies with respect to factors that made monitoring difficult and the strategies that operators have developed to facilitate monitoring. We found that what makes monitoring difficult is not the need to identify subtle abnormal indications against a quiescent background, but rather the need to identify and pursue relevant findings against a noisy background. Operators devised proactive strategies to make important information more salient or reduce meaningless change, create new information, and off-load some cognitive processing onto the interface. These findings emphasize the active problem-solving nature of monitoring, and highlight the use of strategies for knowledge-driven monitoring and the proactive adaptation of the interface to support monitoring. Potential applications of this research include control room design for process control and alarm systems and user interfaces for complex systems.

Supporting operator problem solving through ecological interface design

This paper describes two experiments evaluating ecological interface design (EID), a novel theoretical framework for the design of interfaces for complex human-machine systems. According to EID, to properly support operator problem solving activities, an interface should display both the physical and functional properties of the work domain in the form of a multilevel representation based on the abstraction hierarchy. To evaluate this claim, two interfaces for a thermal-hydraulic process simulation were developed, one based on a traditional format containing only physical information (P) and another based on EID which also contained information about higher-order functional variables (P+F). The findings of Experiment 1 are consistent with the claim that an interface based on an abstraction hierarchy representation can provide more support for problem solving than an interface based on physical variables alone, thereby providing some initial support for the EID framework. There was also some evidence to indicate that theoretical expertise is required to enjoy the full benefits of the P+F interface. The findings of Experiment 2 indicate that subjects who exhibited effective diagnosis performance using the P+F interface tended to start their search at a high level of abstraction and gradually work their way down to more detailed levels, as predicted. Furthermore, previous experience with the DURESS system was found to be the most reliable background variable that predicted performance. >

Programming errors contribute to death from patient-controlled analgesia: case report and estimate of probability

PurposeTo identify the factors that threaten patient safety when using patient-controlled analgesia (PCA) and to obtain an evidence-based estimate of the probability of death from user programming errors associated with PCA,Clinical featuresA 19-yr-old woman underwent Cesarean section and delivered a healthy infant, Postoperatively morphine sulfate (2 mg bolus, lockout interval of six minutes, four-hour limit of 30 mg) was ordered, to be delivered by an Abbott Lifecare 4100 Plus II Infusion Pump, A drug cassette containing I mg·mL−1 solution of morphine was unavailable, so the nurse used a cassette that contained a more concentrated solution (5 mg·mL−1), 7,5 hr after the PCA was started, the patient was pronounced dead. Blood samples were obtained and autopsy showed a toxic concentration of morphine. The available evidence is consistent with a concentration programming error where morphine 1 mg·mL−1 was entered instead of 5 mg·mL−1, Based on a search of such incidents in the Food and Drug Administration MDR database and other sources and on a denominator of 22,000,000 provided by the device manufacturer, mortality from user programming errors with this device was estimated to be a low likelihood event (ranging from 1 in 33,000 to 1 in 338,800), but relatively numerous in absolute terms (ranging from 65–667 deaths).ConclusionAnesthesiologists, nurses, human factors engineers, and device manufacturers can work together to enhance the safety of PCA pumps by redesigning user interfaces, drug cassettes, and hospital operating procedures to minimize programming errors and to enhance their detection before patients are harmed.RésuméObjectifDéterminer les facteurs qui mettent en danger la sécurité des patients qui utilisent l’analgésie auto-contrôlée (AAC) et obtenir une estimation de la probabilité de décès basée sur des preuves, à partir des erreurs de programmation de l’AAC.Éléments cliniquesUne femme de 19 ans a donné naissance, par césarienne, à un enfant en bonne santé. Après l’opération, du sulfate de morphine (boius de 2 mg, période réfractaire de 6 min, limite de 30 mg en 4 h), a été administré avec une pompe à perfusion Abbott Lifecare 4100 Plus II. Une cassette de médicament contenant une solution de 1 mg·mL−1de morphine n’étant pas disponible, l’infirmière a utilisé une solution plus concentrée (5 mg·mL−1). On a constaté le décès de la patiente 7,5 h après le début de l’AAC. Les échantillons de sang et l’autopsie ont montré une concentration toxique de morphine. La preuve présentée est compatible avec une erreur de programmation de la concentration alors que 1 mg·mL−1de morphine plutôt que 5 mg·mL−1 était noté. Fondée sur une recherche d’incidents semblables dans la base de données MDR de la Food and Drug Administration et dans d’autres sources, et selon un ensemble de 22 000 000 de données fournies par le fabricant du dispositif, la mortalité résultant d’erreurs de programmation par l’utilisateur a été estimée comme un incident de faible occurrence (de 1 sur 33 000 à 1 sur 338 800), mais relativement important en valeur absolue (de 65 à 667 décès).ConclusionLes anesthésiologistes, le personnel infirmier, les ergonomes et ies fabricants d’appareils peuvent collaborer à l’amélioration de la sécurité des pompes à AAC en repensant les interfacesutilisateurs, ies cassettes de médicaments et les modes d’emploi hospitalier, ce qui peut réduire ies erreurs de programmation et hâter leur détection avant que les patients en souffrent.

Spectral analysis of sinus arrhythmia: a measure of mental effort

To resolve the uncertainty and disagreement that currently exists in the field of mental workload, a unified research approach is required. It is argued that a promising path would be to identify the various dimensions of mental workload and then to develop a metric for each of these. The present study focused on the dimension of mental effort. In particular, the validity of spectral analysis of sinus arrhythmia as a measure of mental effort was investigated using a psychomotor task. The strong correlation observed between the physiological measure and subjective ratings of effort suggest that spectral analysis of sinus arrhythmia is an accurate measure of operator effort. Results also indicate that the intensity of effort invested by subjects could not be inferred from objective task difficulty or performance. Thus, it is important that a measure of effort be included in experiments investigating mental workload. Future research will be directed at developing a continuous measure of operator effort by implementing the physiological measure on-line.

Making the abstraction hierarchy concrete

The abstraction hierarchy (AH) is a multileveled representation framework, consisting of physical and functional system models, which has been proposed as a useful framework for developing representations of complex work environments. Despite the fact that the AH is well known and widely cited in the cognitive engineering community, there are surprisingly few examples of its application. Accordingly, the intent of this paper is to provide a concrete example of how the AH can be applied as a knowledge representation framework. A formal instantiation of the AH as the basis for a computer program is presented in the context of a thermal-hydraulic process. This model of the system is complemented by a relatively simple reasoning mechanism which is independent of the information contained in the knowledge representation. This reasoning mechanism uses the AH model, along with qualitative user input about system states, to generate reasoning trajectories for different types of events and problems. Simulation outputs showing how the AH model can provide an effective basis for reasoning under different classes of situations, including challenging faults of various types, are presented. These detailed examples illustrate the various benefits of adopting the AH as a knowledge representation framework, namely: providing sufficient representations to allow reasoning about unanticipated fault and control situations, allowing the use of reasoning mechanisms that are independent of domain information, and having psychological relevance.

Inducing effective operator control through ecological interface design

Abstract Ecological Interface Design (EID) is a theoretical framework for designing interfaces for complex human-machine systems. This article investigates the utility of EID in inducing effective real-time operator control performance during both normal and abnormal conditions. Two interfaces for a thermal-hydraulic process were compared, an EID interface based on physical and functional (P+F) system representations and a more traditional interface based solely on a physical (P) representation. Subjects were given 4 weeks of daily practice with one of the two interfaces before their performance on normal events and unfamiliar faults was evaluated. Under normal conditions, there was no performance difference between the P+F and P interfaces. However, dual task results indicate that the P interface loads more on verbal resources, whereas the P+F interface loads more on spatial resources during normal trials. Furthermore, a process tracing analysis of the fault trials showed that the P+F interface led to faster fault detection and more accurate fault diagnosis. Moreover, the P+F subjects exhibited a more sophisticated and effective set of fault management strategies that are similar to those observed in field studies of experienced operators in complex human-machine systems. In addition, a deficiency of the P+F interface was identified, suggesting a need for integrating historical information with emergent feature displays. Collectively, these findings have significant practical implications for the design of advanced computer interfaces for complex industrial systems.

Local applications of the ecological approach to human-machine systems

Contents: Preface. W. Schiff, W. Arnone, Perceiving and Driving: Where Parallel Roads Meet. S.B. Flynn, T.A. Stoffregen, Perceiving and Avoiding Rollover in Agricultural Tractors. J.M. Flach, R. Warren, Low-Altitude Flight. J. Grosz, R.T. Rysdyk, R.J. Bootsma, J.A. Mulder, J.C. van der Vaart, P.C.W. van Wieringen, Perceptual Support for Timing of the Flare in the Landing of an Aircraft. G.E. Riccio, Coordination of Postural Control and Vehicular Control: Implications for Multimodal Perception and Simulation of Self-Motion. G.J.F. Smets, Designing for Telepresence: The Delft Virtual Window System. J.P. Hansen, Representation of System Invariants by Optical Invariants in Configural Displays for Process Control. L.A. Whitaker, V.G. CuQlock-Knopp, Human Exploration and Perception in Off-Road Navigation. H.L. Pick, M.R. Heinrichs, D.R. Montello, K. Smith, C.N. Sullivan, W.B. Thompson, Topographic Map Reading. R.R. Hoffman, R.J. Pike, On the Specification of the Information Available for the Perception and Description of the Natural Terrain. G. Klein, B.W. Crandal, The Role of Mental Simulation in Problem Solving and Decision Making. M.F. Young, M.D. McNeese, A Situated Cognition Approach to Problem Solving. L.D. Segal, Designing Team Workstations: The Choregraphy of Teamwork. P.N. Kugler, G. Lintern, Risk Management and the Evolution of Instability in Large-Scale, Industrial Systems.