Abstract: The autonomic nervous system has a regulatory
structure that helps people adapt to changes in their environment by
adjusting or modifying some functions in response to stress, and regulating involuntary function of human organs. The purpose of this
study was to investigate the effect of combined stimulation, both
far-infrared heating and chiropractic, on the autonomic nervous system
activities using thermal image and heart rate variability. Six healthy subjects participated in this test. We compared the before and after
autonomic nervous system activities through obtaining thermal image
and photoplethysmogram signal. The thermal images showed that the
combined stimulation changed subject-s body temperature more
highly and widely than before. The result of heart rate variability
indicated that LF/HF ratio decreased. We concluded that combined
stimulation activates autonomic nervous system, and expected other
possibilities of this combined stimulation.
Abstract: Many medical devices are driven by motor pumps. Some researchers reported that the vibration mainly affected medical devices using a motor pump. The purpose of this study was to examine the effect of stiffness and damping coefficient in a 3-dimensional (3D) model of a motor pump and spring. In the present paper, experimental and mathematical tests for the moments of inertia of the 3D model and the material properties were investigated by an INSTRON machine. The response surfaces could be generated by using 3D multi-body analysis and the design of experiment method. It showed that differences in contours of the response surface were clearly found for the particular area. Displacement of the center of the motor pump was decreased at K≈2000 N/M, C≈12.5 N-sec/M. However, the frequency was increased at K≈2000 N/M, C≈15 N-sec/M. In this study, this study suggested experimental technique for vibration reduction for a motor pump in medical device. The combined method suggested in this study will greatly contribute to design of medical devices concerning vibration and noise intervention.