Measurement produce a universal standard for there are

Measurement is important to our life. It is an investigational way a person can acquire
new knowledge
about a new or existing object around us. It is closely correlated
with activities
concerning commercial,
industrial, scientific,
and human aspects. Measurement
can be acquiring new
knowledge about a person’s height or weight, the distance
between point A to point B, the size of an atom, or even the
time it takes to build a building. Measurement
is needed in almost every activity that people are doing. Measurement circumscribes different fields such as medical sciences,
communications, energy, environment, food sciences, trade, transportation, and military applications. Its applications to the world is endless
as long as people needs it for almost all the fields that helps the world
improve 1. Measurement is done with the help of an instrument. An instrument is a device or a system which is designed
such that it maintains
a functional
relationship between
a prescribed
property of a substance
and a physical variable
and communicates the relationship to a human observer. It is the one responsible
for the measuring of a specific
object being measured and also outputs
the result to person measuring the object 2.


Each type of measurement
uses a standard which are used to define units where measurement depends.
Early standards
are based on human body such as the length of a man’s hand, the width of his thumb, the distance between
outstretched fingers,
the length of one’s foot, a certain
number of paces, the length of the forearm from the tip of the middle finger to end of the elbow, etc.
3. That kind of measurement
standard is called the royal cubit, a standard
of measure
that is based on a human characteristics. It is mainly used in the middle east as their standard of measurement. Many definitions seem to agree on this aspect of the unit, yet it does not produce a universal standard for there are many ways to determine a cubit. It can be measured from the elbow to the base of the hand, from the elbow to the tip of the middle finger, or from the elbow to a distance located between the outstretched thumb and little finger. It may produce different result from different observer that is why it has not yet produce a recognized measurement standard. It produces errors on every measurement by individual observer that might result to an even bigger problem when used on a bigger scale and different calculations 4.


The measurement
standards evolved
through time and developed
a more accurate way of measuring
an object. During the
3000 BC, Royal cubit was used as the measurement
standard. It was changed
to feet during the 16th century
then used yard in the 18th century. It was then later replaced by meter and wavelength standard
during the 19th century
5. Today, we are following
the SI Units or the International System of Units which is approved by the International Organization for Standardization or ISO. It uses meter as a standard measurement
for length, kilogram for mass, seconds
for time, Ampere for current, Kelvin for temperature,
Candela for luminous intensity,
and mole for amount of substance.
It also defines the supplementary base units called the plane angle or the radian which is formed in the center of a circle of radius 1 and the solid angle or the steradian
which is formed in a center of a sphere of area and radius 1. Unlike the royal cubit, the SI Unit is widely recognized because
the instruments
used in acquiring measurements uses the SI Unit and has produced
less error than the royal cubit has produced.
It also has been more effective
in outputting
stable measurement
results 6.


But these type of measurements are not error proof. Even though it produces less errors than the ancient
royal cubit, it can still produce
errors which may affect the result acquired by an observer.
Errors can arise from many causes and some may be fixed and some may damage the intrinsic properties
of the measurement system. Gross Error is an error you can get when measuring
an object. It is caused by human mistakes.
Another type of error is the System Error which occurs when the instrument used is faulty, uncalibrated, or old. It may also be caused by the random noise the instrument
picks up
7. Random Error may also occur in measurements when results of each measurement
is varying
inconsistently. When a measurement
is free of any random error, it can then be categorized as a reliable
measurement and when it is both free of random and systematic error it can then be categorized as a valid measurement 8. A
good example
for this is the uncertainty of x-ray computed tomography
which is up until this date can provide
doubtful results.
XCT’s measurement uncertainty
is unquantified regarding comparability to other measurement
devices and traceability to national standards
16. Knowing the measurement uncertainty
of an instrument is useful. It can help improve and somewhat fix or remove the error in the result of the measurement
of a specific instrument.
It can help the observer know where and how a problem is occurring during a measurement
and can take actions
fix or somehow reduce the error it is providing 


Reducing errors from the obtained results
can be difficult, a simple fault within a system such as bent meter needles
and poor cabling practices
can usually
be difficult
to see but can easily be corrected inexpensively once they have been identified.
The complete
analysis of a system before use is very much needed to reduce errors that can bug measurements. Instrument
design also plays a big factor in measurement
especially when measuring the environment in the outdoors
as measurement
errors may be caused by environmental issues. All instruments
suffer drift in their characteristics, and the rate at which this happens
depends on many factors,
such as the environmental conditions in which instruments are used and the frequency
of their use. Calibration
of an instrument is a very important consideration in measurement systems
for it  to adapt to changes in the environment
where the measuring takes place. The operator of the measurement
system also plays a big part in reducing
errors on measurements can considerably reduce errors at the output by calculating the effect of a systematic errors and making appropriate correction to the instrument readings. Especially
those errors of either system disturbance
while measuring
takes place or environmental change.  Those are just some ways in reducing
errors in measurements. Reducing
errors can vary from different instances


Measurement of any quantity
plays a vital role not only in science
or engineering,
but it plays a huge part in our day to day life and activities.
The technology
of measurement
is the basis of advancement of science. Discoveries
in the fields of science can build new equipment or tools for measuring, tools that can be more accurate than previous equipment
used or tools that can measure
something that is previously
unmeasurable 10. Because of the widespread
use of computers, use of computer-based measurement
systems are significantly increasing.
Computer-based measurement systems
are usually
a very simple system composed of one computer
and an instrument of choice. Instruments
may be sensors that can measure
different kinds of measurement
standard like distance, temperature,
etc. 11. It
may be anything that can measure
like machines.
Optical measuring
machines are used especially
in the fields of dimensional metrology
which needs huge amount of scanning
points from the image of the object being measured. The scanning points will be processed by the computer
and then output the measurement of the object. But it may result to some uncertainty in the measurement
result 17.


Because of the significant
increase in the use of computer-based measurement
systems, Computer-Based Measurement
Systems are used in almost all fields to help in the works of specific
fields. The field of meteorology integrated
a computer-based measurement
system to a stationary
platform (simple mast or tall tower) or on a moving platform which measures communication signals and radio signal 12. Measurement Technology for Micro-Nanometer Device was developed
which is used to determine the relationship between
a set of coordinates
such as distance and length in order to determine the size, shape, and mutual position detection
of a specific sample
13. Those are just some examples of fields that are now incorporating computer-based measurement
systems to their work for the simplification of the process
as well as minimizing
the time it needs to acquire
specific data from an object.


Development and improvement on computer-based measurement systems
are inevitable
because of its widespread
use, as well as implementations of faster and more accurate
ways to improve measurements. With the fast improvement of technology, faster and precise
measurement systems
will not be a problem. Just like the implementation of CAN Bus based measurement
system on a FGPA Development Kit which concludes
that it was able to measure
channels faster
14. Or the use of digital image and signal processing techniques
that are also implemented
in computer-based measurement
techniques which uses a brain-computer
interface for its processing
which helps in the field of computer vision
15. Or the measurement of skin-electrode
impedance which can provide
information about the skin prior, during or after ECG (Electrocardiogram) or EEG (Electroencephalogram) acquisitions with the use of some test circuits with known resistance
and capacitor
value at different frequencies
which helps in the medicine as it can help doctors
evaluate a patient’s result in an ECG and/or EEG test
18. Or the way distance
can be measured correctly
with the use of dual-comb interferometry with multi-channel
digital lock-in phase detection which is a very helpful
and easy way distance
can be measured 19. Or the improvement of the
measurement consistency in tomography using the dual energy approach which
enables new possibilities in measurement as well as challenging the old ways of
measuring objects. This reduces some of the uncertainties of the results using
computed tomography 21. These are just some measurement
systems that have improved
through time and will still be improving as technology improves.