摘要:

A haemodynamic monitoring and control task was used to evaluate the ecological approach to interface design for complex high-technology environments. Guidelines proposed by Bennett and Flach (1992) were used to design multilevel displays that made visible (a) anatomical constraints, and (b) causal constraints on haemodynamic systems. These displays were compared with a traditional display that showed pressure and flow values in five separate graphs. Simulations of clinical problems were generated by a computer model and presented in an interactive computer environment. Critical care nurses and nursing students observed changes in pressures and flow corresponding to certain disease states and corrected those states using simulated drugs. For both groups, speed and accuracy were progressively improved by the enhanced, multilevel displays.

ISSN:0014-0139    

DOI:10.1080/001401397188341

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

This paper reviews results of comparisons between novice and expert operators in the supervision of dynamic environments. Firstly, the characteristics of expertise and its operational definitions are discussed. Secondly, the main dimensions of the complexity of these environments are described and the difficulties operators have in coping with complexity are examined. Research work carried out in field studies is then overviewed in order to assess the role of expertise in the three components of process control: monitoring, diagnosis and decision-making and executive control. The discussion stresses the convergent results of various studies. In spite of the diversity of task domains and of novice-expert definitions, results converge on three points: experts are better at producing inference, in anticipating, and have a more functional view of the process. Divergent results on directionality of reasoning, depth of knowledge in relation to performance and synchronization of actions are also discussed. Finally, further research trends are outlined.

ISSN:0014-0139    

DOI:10.1080/001401397188350

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

There are many possible means of determining exposure ranging from self-reports of physical exposure to measures of muscle activations and estimated spinal loads. In epidemiologic studies, issues of validity make instrumented measures preferable, however issues of cost and practicability tend to force investigators to less costly but less valid and less reliable measures of exposure, such as self-report questionnaires. This paper presents a method by which estimates of exposure from self-report questionnaires, expert observers, work sampling, video analysis and electromyograms can be reported in a common metric, Newtons of force on a tissue, and show, as an example of its application, estimation of spinal compression on auto workers. A common metric allows a flexible approach to selection of measurement methods in occupational settings: no matter which instrument is used the results can be combined to provide an overall picture of exposure. This approach to exposure assessment for the low back allows for comparability across studies and settings.

ISSN:0014-0139    

DOI:10.1080/001401397188369

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

This laboratory experiment was designed to compare reaction times to brake signals when they appear with red or yellow turn signals. The subject's task was to respond as quickly as possible to the onset of peripherally presented brake lamps, while engaged in a central tracking task. There were three lamp conditions: brake lamps alone, brake lamps while turn signal was on, and a turn-signal lamp alone. The results showed that yellow turn signals, in comparison to red turn signals, led to significantly shorter reaction times to brake signals.

ISSN:0014-0139    

DOI:10.1080/001401397188378

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

As human-machine interfaces grow more immersive and graphically-oriented, virtual environment systems become more prominent as the medium for human machine communication. Often, virtual environments (VE) are built to provide exact metrical representations of existing or proposed physical spaces. However, it is not known how individuals develop representational models of these spaces in which they are immersed and how those models may be distorted with respect to both the virtual and real-world equivalents. To evaluate the process of model development, the present experiment examined participant's ability to reproduce a complex spatial layout of objects having experienced them previously under different viewing conditions. The layout consisted of nine common objects arranged on a flat plane. These objects could be viewed in a free binocular virtual condition, a free binocular real-world condition, and in a static monocular view of the real world. The first two allowed active exploration of the environment while the latter condition allowed the participant only a passive opportunity to observe from a single viewpoint. Viewing conditions were a between-subject variable with 10 participants randomly assigned to each condition. Performance was assessed using mapping accuracy and triadic comparisons of relative inter-object distances. Mapping results showed a significant e ffect of viewing condition where, interestingly, the static monocular condition was superior to both the active virtual and real binocular conditions. Results for the triadic comparisons showed a significant interaction for gender by viewing condition in which males were more accurate than females. These results suggest that the situation model resulting from interaction with a virtual environment was indistinguishable from interaction with real objects at least within the constraints of the present procedure.

ISSN:0014-0139    

DOI:10.1080/001401397188387

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Computer operators at two work sites (n=73, n=19) were prompted to take three 30-s and one 3-min break from computer work each hour in addition to conventional rest breaks. Some operators were asked to perform stretching exercises during the short breaks. Mood state and musculoskeletal discomfort were assessed at each work site over a 2- or 3-week baseline period and a 4- or 6- week treatment period, respectively. Operator productivity measures were obtained from company records. Operators complied with about half of the added breaks but favoured 3-min breaks over 30-s breaks. No improvement in productivity or well-being was found at the larger work site. At the smaller work site, productivity, eye, leg and foot comfort all improved when the short breaks included stretching exercises. These results provide evidence that frequent short breaks from continuous computer-mediated work can benefit worker productivity and well-being when the breaks integrate with task demands.

ISSN:0014-0139    

DOI:10.1080/001401397188396

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

A study is described that examines training of what is termed a 'structural' faultfinding strategy. Such a strategy involves reasoning about the structuralfeatures of a problem domain in order to interpret symptoms and narrow down the area in which the fault lies. Training was carried out using verbal descriptions and schematic representations of the flow through five chemical plants. Training for this structural fault-finding strategy involved three components: identification of plant characteristics (e.g. direction of flow, type of logic gate); production of the symptom propagation pattern of a given failure; and identification of all possible failed items given a specified pattern of symptom propagation. The effectiveness of the structural strategy was assessed in terms ofthe number of failed items identified correctly for novel symptom patterns at three levels of transfer comprising: familiar plants; novel plants with familiar structural features; and truly novel plants where the structural features are extended and combined in novel ways. Transfer of training was positive at all three transfer levels such that errors of both omission and commission were reduced in comparison to a control condition. Further training and assessment was provided concerning fault-finding. While no improvement in fault-finding accuracy was found as a result of training in the structural strategy, data concerning instrument readings requested prior to diagnosis, indicated that this training had a beneficial e ffect. It is suggested that a structural strategy is of benefit during the initial stage of fault-finding but needs to be trained and combined with other types of knowledge that support subsequent stages of the diagnostic process.

ISSN:0014-0139    

DOI:10.1080/001401397188404

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

ISSN:0014-0139    

DOI:10.1080/001401397188413

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

ISSN:0014-0139    

DOI:10.1080/001401397188422

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor