SIMPLE CALIBRATION
PRINCIPLES AND HISTORY
CALIBRATION
Calibration is a comparison between measurements – one of known
magnitude or correctness made or set with one device and another measurement
made in as similar a way as possible with a second device.
The device with the known or
assigned correctness is called the standard. The second device is the unit
under test, test instrument, or any of several other names for the device being
calibrated.
CALIBRATION HISTORY
The words "calibrate"
and "calibration" entered the English language during the American
Civil War, in descriptions of artillery. Many of the
earliest measuring devices were intuitive and easy to conceptually validate.
The term "calibration" probably was first associated with the precise
division of linear distance and angles using a dividing engine and the
measurement of gravitational mass using a weighing scale. These two forms of
measurement alone and their direct derivatives supported nearly all commerce
and technology development from the earliest civilizations until about 1800AD.
The Industrial Revolution
introduced wide scale use of indirect measurement. The measurement of pressure
was an early example of how indirect measurement was added to the existing
direct measurement of the same phenomena.
Before the Industrial
Revolution, the most common pressure measurement device was a hydrostatic manometer,
which is not practical for measuring high pressures. Eugene Bourdon fulfilled
the need for high pressure measurement with his Bourdon tube pressure gage.
In the direct reading
hydrostatic manometer design on the left, unknown pressure pushes the liquid
down the left side of the manometer U-tube (or unknown vacuum pulls the liquid
up the tube, as shown) where a length scale next to the tube measures the
pressure, referenced to the other, open end of the manometer on the right side
of the U-tube. The resulting height difference "H" is a direct
measurement of the pressure or vacuum with respect to atmospheric pressure. The
absence of pressure or vacuum would make H=0. The self-applied calibration
would only require the length scale to be set to zero at that same point.
In a Bourdon tube shown in the
two views on the right, applied pressure entering from the bottom on the silver
barbed pipe tries to straighten a curved tube (or vacuum tries to curl the tube
to a greater extent), moving the free end of the tube that is mechanically
connected to the pointer. This is indirect measurement that depends on
calibration to read pressure or vacuum correctly. No self-calibration is
possible, but generally the zero pressure state is correctable by the user.
Even in recent times, direct
measurement is used to increase confidence in the validity of the measurements.
In the early days of US automobile
use, people wanted to see the gasoline they were about to buy in a big glass
pitcher, a direct measure of volume and quality via appearance. By 1930, rotary
flow meters were accepted as indirect substitutes. A hemispheric viewing window
allowed consumers to see the blade of the flow meter turn as the gasoline was
pumped. By 1970, the windows were gone and the measurement was totally
indirect.
Indirect measurement always
involves linkages or conversions of some kind. It is seldom possible to
intuitively monitor the measurement. These facts intensify the need for
calibration.
Most measurement techniques used
today are indirect.
BRAIN-BODY CALIBRATION was discovered by David
Rubenstein, PhD from new revelations on how to trigger the brain to use more of
its own resources to affect every aspect of human health and performance. The
prime discovery is a brain program all of us are born with we never knew
existed in two centuries of neuroscience. This brain program lays dormant all
our lives – triggered
only from the Brain-Body Calibration technique immediately causing massive
brain-body improvements. The
name of this newly discovered brain program is the “Synaptic Optimization Program” and is apparently located in the cerebellum of the
brain.
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