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Measurement of the Hand Transmitted Vibration of the Human Hand Arm System During Operation of a Hand Tractor
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Leafy vegetable cultivation involves strenuous physical activity. Mechanization increases work speed and field capacity, reducing human energy expenditure per unit area, but increases heart rate.

Keywords:
Agricultural mechanizationfield capacityhuman energy expenditureleafy vegetable cultivationworker

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Area of Science:

  • Agricultural Engineering
  • Occupational Health
  • Human Physiology

Background:

  • Leafy vegetable cultivation (LVC) remains labor-intensive, posing significant physical demands on workers despite mechanization efforts.
  • Heavy physical activities in LVC contribute to physiological strain among agricultural workers globally.

Purpose of the Study:

  • To evaluate the human physiological strains experienced by workers in leafy vegetable cultivation.
  • To identify factors influencing physiological strain and their relationships within LVC operations.

Main Methods:

  • Thirty male workers participated in the study, with working heart rate (HR) monitored using sensors.
  • Work speed (field capacity, FC) was calculated by timing operations over a set area.
  • Pearson correlation and linear regression analyzed relationships between HR, FC, mechanization status (MS), and energy expenditure.

Main Results:

  • Seedbed preparation showed the highest HR (120.1 beats/min), while manual harvesting had the lowest (87.8 beats/min).
  • Manual operations using hoes (seedbed preparation, manure application, irrigating) imposed the greatest physiological strain.
  • Mechanized operations demonstrated higher field capacity (FC).

Conclusions:

  • Increased area treatment speed, influenced by mechanization status (MS) and field capacity (FC), correlates with lower human energy consumption per unit area.
  • Heart rate (HR), as a measure of physiological strain over time, positively correlates with the speed of human energy expenditure.