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Related Concept Videos

Fatigue01:21

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Fatigue occurs when materials rupture under repeated or fluctuating loads, even at stress levels far below their static breaking strength. It typically results in brittle failure, even for ductile materials. It is a critical consideration in designing machines and structural components subjected to repetitive or varying loads. The nature of these loadings can range from fluctuating loads like unbalanced pump impellers causing vibrations to repeatedly bending a thin steel rod wire back and forth...
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Fatigue, in the context of materials science and engineering, refers to the weakening or failure of a material caused by repeatedly applied loads, even if these loads are below the strength limit of the material. Fatigue strength in concrete is a critical property that influences its durability and longevity. Concrete can fail in two ways due to fatigue. Static fatigue or creep rupture occurs under a constant load or one that increases slowly. The other failure mode is due to cyclical or...
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Collecting Sleep, Circadian, Fatigue, and Performance Data in Complex Operational Environments
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The Case for Addressing Operator Fatigue.

Jeanne F Duffy1, Kirsi-Marja Zitting1, Charles A Czeisler1

  • 1Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital and Division of Sleep Medicine, Harvard Medical School.

Review of Human Factors and Ergonomics
|June 10, 2015
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Summary

Sleep deficiency is widespread, impairing vigilance and attention critical for safe transportation. Drowsy driving and operating vehicles increases accident risks for everyone involved.

Keywords:
Biological rhythm, circadiandrowsinessfatiguehomeostatic sleep-wake regulationhours of workindividual differencessleep inertiasleep-wake propensity

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Area of Science:

  • Transportation Safety
  • Sleep Medicine
  • Human Factors

Background:

  • Sleep deficiency is a prevalent issue in the U.S., affecting individuals in safety-sensitive transportation roles.
  • Fatigue and sleepiness significantly impair critical functions like vigilance, attention, reaction time, and decision-making.
  • Drowsy operation of vehicles, aircraft, trains, and vessels poses substantial risks for errors and accidents.

Purpose of the Study:

  • To explore factors contributing to sleepiness in transportation.
  • To present evidence on the impact of sleepiness on transportation safety.
  • To review methods for measuring sleepiness and existing interventions.

Main Methods:

  • Literature review of laboratory and field studies.
  • Analysis of accident investigation data and survey results.
  • Examination of sleepiness measurement techniques and intervention strategies.

Main Results:

  • Sleepiness compromises essential cognitive functions, increasing the likelihood of transportation errors and accidents.
  • Numerous individuals operate transportation systems while drowsy, endangering themselves and the public.
  • Current knowledge on sleepiness measurement and interventions in transportation settings is being synthesized.

Conclusions:

  • Sleep deficiency is a critical threat to transportation safety.
  • Further research is needed to fill knowledge gaps regarding sleepiness and its management in transportation.
  • Effective interventions are crucial to mitigate risks associated with drowsy operation.