Ergonomic design in ancient Greece.

Although the science of ergonomics did not actually emerge until the 20th century, there is evidence to suggest that ergonomic principles were in fact known and adhered to 25 centuries ago. The study reported here is a first attempt to research the ergonomics concerns of ancient Greeks, on both a conceptual and a practical level. On the former we present a collection of literature references to the concepts of usability and human-centred design. On the latter, examples of ergonomic design from a variety of fields are analysed. The fields explored here include the design of everyday utensils, the sculpture and manipulation of marble as a building material and the design of theatres. Though hardly exhaustive, these examples serve to demonstrate that the ergonomics principles, in content if not in name, actually emerged a lot earlier than is traditionally thought.

Ergonomic redesign of the electric guitar.

The present study deals with the redesign of the electric guitar, considering ergonomic criteria. Difficulties met by novice musicians, neuro-muscular fatigue caused by guitar playing and occupational diseases occurring to professional guitarists, justify this study. Characteristics of existing electric guitar models which add to musician's fatigue or difficulty, were identified. A number of ergonomic requirements were then derived. The redesign process tried to satisfy these requirements, considering at the same time musical requirements and technical constraints. A comparative evaluation of the designed ergonomic guitar with three existing electric guitar models, showed that although the designed electric guitar preserves the main features of the instrument, it achieves better user fit.

Factors affecting accuracy of producing time intervals.

The present study assessed the accuracy of producing time intervals. 92 subjects were asked to produce three different time intervals (15, 30, and 60 sec.) under six experimental conditions during which they performed concurrent tasks of different cognitive difficulty and requiring different cognitive functions. Real-life working situations guided the design of the experiment. Accuracy of time estimation was significantly affected by the length of the intervals to be produced and the concurrent tasks performed. 15-sec. intervals were more accurately estimated. Accuracy decreased as the cognitive demands of the concurrent tasks increased; subjects systematically overestimated the duration of the intervals. Having an activity requiring time estimation seems to have a positive effect on the accuracy of time estimation. The same was found for certain strategies aiding time estimation which were used spontaneously by certain subjects. No significant difference in the accuracy of estimation between women and men was found.