Our Week in NSA Advanced Biomed

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Our Week in NSAAdvanced Biomed

• By Zach, Sara, Justice, and Vishal

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The Vision Experiment with Changbao

• Changbao took us to the chemistry building, where
  he performed an experiment testing our vision
  involving the observation of road signs with
  different lightings in nighttime conditions. With
  the lights off, each of us at separate times
  stood about 60 feet away from the movie
  projection with the picture of the road sign. We
  walked along an illuminated strip of red light
  until we could see the road sign and spell it
  (not necessarily with comfort). If we got it
  right, we recorded the distance we were away from
  the projection. Then we keep on walking forward
  until we can see the sign comfortably. Again, we
  recorded the distance we were away from the
  projection. We did this several times with the
  lighting of the signs changing. From these
  results a graph was constructed.

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Viewable Distance Experiment

• The graphs from this experiment include
  information about the luminants and the contrast
  of the sign. From the graph you can conclude
  that in general, as the contrast ratio goes up,
  the viewable distance goes up. Also, depending
  on the luminance, there is a point at where the
  viewable distance peaks.

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Graphs From Luminance Variability Experiment
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Introduction to the Comfort Experiment

• This week at NSA, our group worked with our
  project director Sonny on a project dealing with
  the physiological measurement of comfort. We
  developed an experiment and tested it, using our
  results to come to a conclusion about the effects
  of comfort/discomfort on the body.

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Rationale

• We did this project to find out if comfort can
  be measured by the varying physiological
  measurements on the body.

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Procedure

• The first thing we did was explain to our
  subject exactly what we were doing during the
  experiment. We explained to him how the Biopac
  system works and how we were going to take his
  measurements.
• After this stage of the experiment, we strapped
  the respiratory belt across the subjects ribcage.
  This belt measured the respiratory rate during
  the experiment.
• Next, we hooked our subject up to the Biopac
  system. Nodes were placed on the right carotid
  artery and at the left external oblique muscle.
  These nodes measured the subjects heart rate with
  an ECG (electro cardio-gram) during the
  experiment.
• The last nodes placed on the subject were placed
  on the left side of the face. These nodes were
  placed on the corrugator, the obicularis oculi,
  the zygomatic, and the masseter muscles. These
  nodes picked up muscle movements during the
  experiment, also called an Electro myo-gram
  (EMG).

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Procedure contd

• All of the nodes were hooked to the Biopac unit,
  which was linked to a computer. The computer
  took the measurements from the Biopac, and
  transferred them into time-frequency graphs.

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Procedure Contd

• After the subject was hooked up to the Biopac,
  we gave him a chart which asked him to rate his
  comfort level from a range of -5 to 5, with -5
  being extreme comfort and 5 being extreme
  discomfort. During the next two parts of the
  experiment, we asked the subject to rate his
  comfort level two more times on the same chart.

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Pictures of Facial Muscles
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Testing Phase One

• We began our experiment by putting our subject
  in an uncomfortable situation that we generated.
  He was told to sit on a high stool and copy a
  report that was in size 6.5 type. The brightness
  and contrast of the computer was increased to the
  maximum level while the lights in the room were
  turned off. The heat in the room was turned up
  to 85 degrees. Also, during testing, we played
  loud, heavy, and offensive rock music. We had
  the subject type for 15 minutes.

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Testing Phase Two

• Phase two began 10 minutes after phase one. This
  time, we put our subject in a relatively
  comfortable situation. He was told to sit in a
  comfortable reclining and swiveling chair and
  copy a report that was in size 12 type. The
  brightness and contrast of the computer was
  lowered to a reasonable level while the lights in
  the room were turned on. The air conditioning in
  the room was turned on to lower the temperature.
  This time, during testing, we played soft,
  soothing, classical music. Once again, we had
  the subject type for 15 minutes.

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Our Results
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Results Cont-ECG, RES
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Results Cont- EMG
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Our Conclusion

• From the charts, we concluded that the only
  physiological measurement that could be used
  reliably to tell if the subject was comfortable
  or not was the heart rate. Of course, we only
  had one subject, so our results are not reliable
  and highly restricted, thus being unable to fully
  prove our hypothesis.