Fatigue and sleepiness are leading contributors to road crashes. Either can occur in the evening, sometime around 10:00 p.m., after a day that begins in the morning, sometime around 8:00 a.m. Other factors contribute as well to performance decrements in the evening for those who regularly work during the day. It is arguably the case that these various factors are responsible for the observed decrements in safety-critical driving skills, such as hazard anticipation, hazard mitigation, and attention maintenance, which occur in the evening. However, it is by no means clear whether a training program can be designed to mitigate the effects that such factors have on these critical driving skills. A simulator experiment was undertaken to determine whether a training program [sleepiness and fatigue evaluation training (SAFE-T)] could lead to improvements in the hazard anticipation, hazard mitigation, and attention maintenance skills of drivers who had been awake for 12 h. The results showed that for all three skills trained drivers performed significantly better during the posttest (after SAFE-T) than the pretest (before SAFE-T), whereas the placebo drivers performed significantly worse during the posttest than the pretest. Fatigue and sleepiness both increased during the posttest from their pretest values. Thus the effects of training are still observed even in the presence of increases in fatigue and sleepiness.
Abstract. This study adopts an output oriented Shephard Distance Function (SDF) to estimate Technical Efficiency (TE) in cattle feedlot under five distinct estimators (Data Envelopment Analysis /DEA/, Free Disposal Hull /FDH/, Order-m, Order-α and Bootstrap). The aim is to rank the efficiency estimates based on descending order of the TE estimates from the five estimators and test the hypotheses of mean difference across the estimators. In addition, the independent variables used in the feedlot system were also ranked based on magnitude to total cost. Results show initial cost of animal, feed cost, water cost, labour cost, depreciation, medicaments and cost of salt lick are ranked 1st, 2nd, 3rd, 4th, 5th, 6th and 7th, respectively, in terms of proportion to total cost. The study found a combination of inappropriate scale of production and managerial problems as the causes of inefficiency in the cattle feedlot. The study advocates for proper pricing of inputs, commensurate and timely utilization of inputs to avert input waste. Similarly, the study recommends up-scaling (178 cattle feedlot) and down-scaling (92 cattle feedlot) the cattle feedlot production owing to their operation at increasing and decreasing returns to scale, respectively, to attain enhanced efficiency.
Background
There have been some concerns related to manual handling of large items in industry. Manual handling operations of large sheet metal may expose workers to risks related to efficiency as well as occupational safety and health. Large sheet metals are difficult to move and burdensome to lift/transfer, and handling the sharp sheet edges may result in contact stress and/or cut injuries on the workers.
Methods
Through observation, interview, and immersive simulation activities, a few problems related to current handling of sheet metals were identified. A sheet metal trolley-lifter was then designed and fabricated to address these issues. A pilot study on the use of the developed trolley-lifter for handling sheet metals was conducted to compare between the new and traditional handling methods.
Results
The pilot study of the trolley-lifter showed promising results in terms of improving the cycle time, manpower utilization, and working postures compared with the traditional handling method.
Conclusion
The trolley-lifter offers an alternative solution to automation and a mechanized assistive device by providing a simple mechanism to assist the handling of sheet metals effectively and safely.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.