operation due to drowsing occurred at a certain rate for any group of drivers, irrespective of the type of train, running sections, weather, and other operative conditions such as train delays, whereas 117 cases of danger caused by unforeseen obstacles on the track were related to site characteristics, and 47 cases of other disorders were frequent in unusual operative conditions such as arrival-departure, poor signal display, wrong instructions, or equipment failure. Thus continued driving under ordinary track conditions at a more or less constant speed was likely to induce drowsiness under the dominant influences of fatigue and time of the day; 79% of such cases occurred between midnight and 6 am. Most drowsing on the second night appeared during the first 2 - 4 h of duty. Effects of monotony and insufficient rest were discussed in relation to recurrent fluctuation in vigilance.
Reports (Report No NASA-TM-X-62464; A-6211). The effects of alternative traffic management possibilities on task performance and pilot controller verbal workloads were studied. Two new rule structures - sequencing and advisory in addition to vectoring were studied in conjunction with CRT pilot displays incorporating traffic situation displays with and without aircraft flight path predictors. The sequencing and advisory systems gave increasing control responsibility to the pilots. It was concluded that distributed management systems could in practice significantly reduce controller verbal workload without reducing system performance. Implications of this conclusion suggest that distributed management would allow controllers to handle a larger volume of traffic safely either as a normal operating procedure or as a failure mode alternative in a highly automated ground centered system.
7.4.14 (69698)
Kuroki, Y. et al. Variation of driver's arousal level during car driving in Japan. Paper presented at the A utomotive Engineering Congress and Exposition, Detroit, Michigan, 2 3 - 2 7 February 1976. Society of A utomotive Engineers, Paper No 76008 I, 1976, 12 pp. The 104 635 cases of rearward collisions that occurred in 1974 accounted for 21% of all traffic accidents, the largest single category of accidents. It is thought that many of these accidents were caused by insufficient driver alertness due to a drop in the level of awareness or responsiveness. Using 18 male subjects, aged from 22 to 29, a test was conducted of reduction in the level of consciousness as determined by continuous measurements during normal driving of EEG, ECG and EOG. Six of the subjects showed a drop in consciousness as indicated by the appearance of an alpha (a) wave of 8 - 1 3 Hz. Such waves appeared most frequently following the noontime meal. It can be postulated that their origin is a temporary state of psychological relaxation produced by a number of factors including mental fatigue, drop in the will to drive caused by phenomena of familiarity and daily bodily rhythms. It can be concluded that drivers must pay special attention to preventing the buildup of fatigue; at the same time, particular care must be taken after ingestion of meals. 7.4.15 (69709)
Kriefeldt, J.G. et al. Verbal workload in distributed air traffic management. In: NASA l l t h Annual Conference on Manual Control, May 1975, pp 4 5 5 - 4 7 1 ; abstr in Scientific and Technical Aerospace
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Hill, A.B. Work variety and individual diffegences in occupational boredom. Journal o f Applied Psychology, Feb 1975, 60.1, 128-131. This study examines the relationship between reported boredom and extraversion, neuroticism, intelligence, age, length of service, and work variety in a sample of 63 women engaged in simple repetitive work. Boredom and fluctuations in feelings of boredom were found to be negatively correlated with age and neuroticism (correlations significant at the 5% level). No significant correlations were found between boredom or fluctuations in boredom and length of service, intelligence, extraversion, or degree of work variety. However, day-to-day fluctuations in boredom were found to be less for older workers having little variety in their work.
Physiology, anthropometry and biomechanics
movements, a recording of the pulse rate and an inquiry into subjective feelings of fatigue and pains by means of a self-rating procedure. The job analysis revealed static work for the trunk and for the right arm. The pulse rate was increased, and in four of five cases the mean work-pulse exceeded the usual limits of tolerance. The selfrated feelings of fatigue and pain showed an increase during the day; the pains in the back and in the right arm seemed to reflect very well the results of the ergonomic analysis.
7.4.18 (69756)
Saha, P.N. Acrobatic capacity of dock workers in Bombay. American Industrial Hygiene Association Journal, Apr 1975, 36.4, 3 1 1 - 3 1 7 ; abstr in CIS Abstracts (CIS 76-280). Investigations with a bicycle ergometer to assess the acrobatic capacity (maximum oxygen uptake capacity) of 61 dock workers employed in lifting and carrying 100 kg grain bags in the Bombay docks are described. A mean value of 2572 -+ 54 ml/min was found, a high value compared with results of studies of other occupations, and indicating better physical fitness than that of other Indian workers. The relationship with age and body weight is examined.
7.4.19 (69761) Shonyo, C. Anthropometry. A bibliography with abstracts ( 1 9 6 4 - J u l y 1975). TRC Report No T76-0840, Aug 1975, 193 pp; abstr in R and D Abstracts. Research studies are abstracted related to anthropometric measurements for use in designing military and civilian protective equipment and clothing, automobile interiors and air bag restraint systems, aircraft cabins, and aircraft seats. Also, reports are cited on design of anatomical models, computerized simulation of the human body and anthropometry as related to the strength of body members and physical fitness.
7.4.17 (69736)
7.4.20 (69763)
Nemeneek, J. and Grandjean, E.
Mareelin, J. and Erulin, F.
Ergonomic study of a difficult task in the textile industry (Etude Ergonomique d'un Travail Penible dans l'Industrie Textile). (In French.) Travail Humain, Jan 1975, 38.1, 167-174.
Study of some anthropometric variables in a sample of 8203 job applicants (Etude de Quelques Variables Anthropometriques Chez 8203 Demandeurs d'Emploi). (In French.) Travail Humain, Jan 1975, 38.1, 149- 166.
A heavy job in a textile factory was investigated. Female workers had to handle and check bobbins weighing 3 kg each. Altogether they handled 2200 to 2900 kg daily. The study included an ergonomic analysis of postures and
AppliedErgonomics December 1976
The anthropometric data of 8203 job applicants in the Paris area (age range ! 6 - 6 5 years) were extracted from the routinely established medical