Suchergebnisse

Twenty-nine audiometric tests undergone by an employee over a 26-year employment period in a structural maintenance shop at a large petrochemical company are analyzed. At retirement, the employee was diagnosed as having irreversible sensorineural hearing loss. Since company studies yielded average noise level measurements of 90 dBA within 1.83 m of operating equipment, the relationship between continuous noise and sensorineural hearing loss in the conversational frequencies is examined. Results suggest that the relationship is linear, and that auditory capability consistently deteriorates over long periods of exposure.

The purpose of this paper is to make practical suggestions regarding the appropriate use and interpretation of the null hypothesis (He) in human engineering research. The coverage of this topic, as presented herein, is neither meant to be restrictive nor exhaustive, but it does represent a simple and concise treatment of a very real methodological problem. The paper itself is offered as a single collective source of several research arguments underlying using and interpreting Ho as an experimental hypothesis.

Two studies are reported. In the first study, reading seven segment numerics (SN) was shown to be more difficult than reading of conventional numerics (CN) under short viewing times. Errors in reading SN were idiosyncratic to certain numbers; however, the numbers erroneously reported are predictable. In the second study, training was shown to be effective in overcoming difficulties in reading SN, but without opportunity for continued exposure to SN, acquired skills may be reduced significantly after one month. It was concluded that where time is not critical, SN readability is comparable to CN, but in situations where time is critical, periodic SN training should be employed to preclude readability problems.

A major problem currently confronting law enforcement agencies is the assessment of the effectiveness of various driver improvement activities. The objectives of this research were to evalute the effect of the Texas Department of Public Safety driver improvement training program on driving record and to develop a technique for predicting reduction in accident and violation frequencies for the 12-month period following training. The results of this study indicated that the training program has a significant effect on accident and violation frequencies for selected groups. It was also found that it is possible to construct an equation that will predict with some accuracy, reduction in the number of accidents and violations for a 12-month period following training.