1,721,119 research outputs found
Modelling of human alarm handling responses times: a case of the Ladbroke Grove rail accident in the UK
Full text linkThe purpose of the paper was to address the timeliness of the signaller's intervention in the Ladbroke Grove rail incident in the UK, as well as to consider the utility of human performance time modelling more generally. Human performance response time modelling is a critical area for Human Factors and Ergonomics research. This research applied two approaches to the same problem to see if they arrived at the same conclusion. The first modelling approach used the alarm initiated activity (AIA) model. This approach is useful for indicating general response times in emergency events, but it cannot comment in detail on any specific case. The second modelling approach employed a multi-modal critical path analysis (CPA) technique. The advantage of the latter approach is that it can be used to model a specific incident on the basis of the known factors from the accident inquiry. The results show that the AIA model produced an estimated response time of 17 s, whereas the CPA model produced an estimated response time of 19 s. This compares with the actual response time of the signaller of 18 s. The response time data from both approaches are concordant and suggest that the signaller's response time in the Ladbroke Grove rail accident was reasonable. This research has application to the modelling of human responses to emergency events in all domains. Rather than the forensic reconstruction approach used in this paper, the models could be used in a predictive manner to anticipate how long human operators of safety-critical systems might take to respond in emergency scenarios
Alarm initiated activities: an analysis of alarm handling by operators using text-based alarm systems in supervisory control systems
No full textAlarms constitute a significant aspect of the operator-system interface in human supervisory control tasks: they have the potential to display information that is of critical importance to overall system safety and integrity. This paper considers the trend toward the use of visual display terminals for the presentation of alarms, specifically in the use of scrolling text displays. It is suggested that this form of information display may not best serve all aspects of alarm handling. To illustrate why this is so, an analysis of human alarm handling activities is presented. The focus on text-based displays and annunciators allows the authors to concentrate on a number of problems associated with the alarm design using a specific medium. From this discussion, the alarm initiated activities model is developed. By considering the activities that people engage in when dealing with alarms, an insight is offered into the information requirements that can be used to inform the design of alarm systems
Error by design: Methods for predicting device usability
No full textThis paper introduces the idea of predicting ‘designer error’ by evaluating devices using Human Error Identification (HEI) techniques. This is demonstrated using Systematic Human Error Reduction and Prediction Approach (SHERPA) and Task Analysis For Error Identification (TAFEI) to evaluate a vending machine. Appraisal criteria which rely upon user opinion, face validity and utilisation are questioned. Instead a quantitative approach, based upon signal detection theory, is recommended. The performance of people using SHERPA and TAFEI are compared with heuristic judgement and each other. The results of these studies show that both SHERPA and TAFEI are better at predicting errors than the heuristic technique. The performance of SHERPA and TAFEI are comparable, giving some confidence in the use of these approaches. It is suggested that using HEI techniques as part of the design and evaluation process could help to make devices easier to use
Validating task analysis for error identification: Reliability and validity of a human error prediction technique
No full textThis paper reports on the theoretical and empirical developments for an error prediction methodology called task analysis for error identification (TAFEI). Other researchers have noted the need for theoretically driven approaches that are able to provide practical utility in error prediction. Theoretical developments include the concept of 'rewritable routines', which describe the loop between cognitive processing, action and devices states. This has been proposed as a way of unifying ideas from systems theory and cognitive psychology. The empirical research shows that TAFEI is superior to heuristic methods, which supports the idea that structured methods assist in error prediction. The validation study shows that TAFEI reaches acceptable levels in terms of test - retest reliability and concurrent validity. It is believed that the method has reached a level of maturity after 10 years of development work. This is demonstrated by the many uses to which the method has been put, including that of a design tool
Observation
No full textObservation of people interacting with a device to perform a task provides a way of capturing data on errors and performance time as well as providing some insight into the ease or difficulty with which the task is performed (Baber and Stanton, 1996; Stanton, 1999; Stanton and Young, 1999). There are many and varied observational techniques, which fall into three broad categories: direct, indirect, and participant observation (Drury, 1995). Ideally, the participants would be representative end users of the system being analyzed, but this is not always possible
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
- …
