Electromagnetics-Ticket
to a better future[1]
Lwee Yong Xin Michael (michaellwee.2013@business.smu.edu.sg), 1st Year student, Bachelor of
Business Management, Singapore Management University
Executive Summary
"I happen to
have discovered a direct relation between magnetism and light, also electricity
and light, and the field it opens is so large and I think rich” -Michael
Faraday
Electromagnetism as
stated by Michael Faraday, is a wide field whose developments has changed the
way we test and develop new technologies from various fields, due to the
interactive nature of the field.
This paper examines
the way electromagnetics have been used as the basis for many technologies in
the past, and how it's application has improved, allowing the incorporation
into current and future technologies to make more efficient machines.
1. Introduction
Electromagnetics
is a broad field, which consists of the studies of electricity and magnetic, this
is due to electricity, and magnetics being intricately related subjects, where
one would always observe both of them at work simultaneously (Woodhouse, 2012).
As such, many of nature's phenomena have relation to electromagnetics, such as
lightning. The study of the subject started since ancient times, where people
tried to find ways to deal with the common phenomena such as lightning
(Muljadi, 2013). One of the world's oldest lightning rods can be found in Sri
Lanka, Anuradhapura Kingdom, which was made thousands of years ago, in order to
protect buildings and monuments (Muljadi, 2013).
The field
is also the basis for many important inventions, which have laid the
foundations for our modern lives, such as the light bulb by Edison (Lusted,
2013). The ground work laid by this field, such as electric circuits,
conduction, or even the study of electromagnetic fields has been incorporated
into almost every single facet of our lifestyles, which range from gadgets to
industrial production processes. The wide and varied use of this field includes
plating, metal extraction, and wireless communications.
One of the
most important discoveries which have helped to shape this field is arguably
Faraday's discovery of electromagnetic, which started to breach the gap in
between electricity and magnetism. His works has been investigated, and further
expended by Maxell resulting in the Maxwell equations (Tweney, 2011). This has
resulted in the birth of other important scientific theories, such as the
electromagnetic spectrum, to the quantum theory (Tweney, 2011). However, it is
also important to note that, the discovery of electromagnetics and its
application might far predate our expectations. Arguably the world's first
battery was discovered in 1938, near Baghdad, evidence of a clay jar with a
copper cylinder encased with a iron bar was found, traces of acidic agents has
also been found in the jar which dates back to around 200 BC (News.bbc.co.uk,
2013). Thus, the study of the field might be more advanced than we could
possibly think in the past.
2. Historical
Perspectives
The history
of electromagnetics is filled with many theories, which have wide applications
in many fields. Thus, many of the world's revolutionary inventions have roots
in this field.
2.1 Electrical
Telegraph
The
electric telegraph is a revolutionary technology; one of the first was created
by Samuel Soemmering in 1809. He used 35 wires, with the ends, electrodes 3.5 kilometres
away immersed in acid. Gas bubbles would be formed in the acidic solution
corresponding to the letter or number (Jones, 1999).
Figure 1 depicting
“Samuel Soemmering’s Telegraph” reproduced from Jones, R. (1999).
This was
subsequently improved upon when new technologies were discovered, in this case,
it was when William Sturgeon invented the electromagnet in the early 19th
century, allowed practical use of magnetic fields in inventions (Electromagnets,
2013).
The most
successful and well-known electrical telegraph was arguably built by Samuel
Morse, which was put into practical use in 1844, when he transmitted the famous
message "What hath God wrought", from Washington to Baltimore (Samuel
Finley Breese Morse,2013).
The
invention of the telegraph helped to bridge communications over long distances,
and was highly successful as it expended worldwide, making world communication
possible for the first time. The telegraph was widely used until the birth of
telephone networks, capable of transmitting voice.
2.2 Radar
Radar
stands for RAdio Detection and Ranging, which uses radio waves as a medium for
detection of other obstacles, be it ships at sea or aircrafts in air. The
technology uses the echolocation of radio waves, with pulsing radio waves from
an antenna and allowing them to rebound and be picked up by the same device
(Woodhouse, 2012).
The
invention of radar did not present any technological advances, or rather it was
a practical realisation of many theories, such as Maxwell's electromagnetic
waves theory, and Heinrich Hertz's subsequent experiments to prove the theory
laid the ground work for the invention (Woodhouse, 2012).
Guglielmo
Marconi succeeded in 1901 in transmitting radio waves over the Atlantic, and
helped establish the ground world for radar, especially when he presented his
description of radio echolocation technique, which became the first detailed
radar concept (Woodhouse, 2012).
The world's
first patent for a radar system happened in 1935, by Scottish scientist Robert
Watson-Watt, who invented the world's first operational radar, which was
capable of detecting aircraft (Woodhouse, 2012).
Figure 2 depicting
“Chain Home” reproduced from TheTimeChamber. (2013).
However,
during that period when there was high risk of war, many countries also
channelled much funding into the research of such systems. One of the most
notable would be "Chain Home", which was constructed on Britain's
eastern coastline, consisting of tall towers with radio transmitters and receivers
built in 1939 at the outbreak of World War 2 (Woodhouse, 2012).
3. Current
Applications
The modern
world is a highly interconnected world, which has leveraged heavily on the advantages
which electromagnetics have bought. There are still many avenues of
electromagnetics which can be improved on, and the theories in the field could
still be applied to better existing technology.
3.1 Maglev
Magnetic
levitation or Maglev for short is a branch of technology which has been gaining
support in recent years. The technology is best known for its uses in
transportations, particularly maglev trains.
The
implementation of such technology in railways has resulted in significant
improvements, such as using less energy and space, able to travel faster
regardless of terrain, with more comfort (Yaghoubi & Ziari, 2013). These
also give rise to the possibility of implementing such technology into other
fields in transportation, and possibly move beyond that.
Maglev
works by generating magnetic fields, which suspends an object without any other
support. This allows objects to achieve a low friction state, which in turn
would help in many industrial processes, or equipment, where the reduction of
friction is vital (Thompson, 2000). The reductions in friction in railways have
seen a drastic reduction in travel times, where currently, the L0 series maglev
trains testing in Japan can hit 500km/hr (Steadman, 2013).
The
viability of applying the maglev technology to other fields is huge, such as in
launching rockets; NASA has a magnetic levitation track at Marshall Space
Flight Centre in Huntsville, America. The magnetic levitation track has the
advantage of using electricity to accelerate a rocket to 600mph, allowing it to
break free of gravity. This allows better efficiency as compared to the
traditional method of using rocket fuel in the launch, thus help reduce the
weight and the costs of the craft (Yaghoubi, 2013).
Figure 3 depicting “NASA’s
magnetic levitation track at Marshall Space Flight Centre” reproduced from
Yaghoubi, H. (2013).
Maglev
technology has been highly effective in improving many technologies, by making
them less energy consuming, and efficient, while being easy to transplant into
other industries such as medicine, where starting plans for maglev technology
to be integrated into artificial hearts (Yaghoubi, 2013). The plans would
improve artificial hearts significantly, as the technology is integrated inside
would help overcome issues of friction, sealing and lubrication in traditional
heart pumps by reducing the damage to blood cells, thus improving the safety
and lifespan of the artificial heart (Yaghoubi, 2013).
The ability
for Maglev to be applied on many fields, while being highly cost effective, due
to the amount of research which has already been conducted, could make it a
technology which we would find in most of the devices in our machines in the
future, due to the positive effects it brings in lowering costs.
3.2 Electromagnetic
Jamming
Electromagnetic
jamming is the act of trying to create devices which aim to disrupt, or prevent
any electromagnetic signals from watching its intended targets. The use of such
technology has been restricted to mainly the military domain for now.
The history
of such jamming started at the same time when radio was first invented, with
cases of attempted corporate espionage, such as in 1899, the rivals of New York
Herald tried to jam their reporting of America's Cup race results (Rounds,
2004).
The act of
jamming has widespread effects on the outcome of war, during the 1905
Russo-Japanese war, the failure to jam the signals sending the location of the
Russian fleet back to the imperial navy, led to a loss where 80% of the Russian
fleet being destroyed (Wilson, 2013).
A main aim
in electromagnetic jamming, especially during the period of strife, targets at
radar systems of ships and aircraft. There is more than a way to do this, and
the methods of doing such have evolved to be more efficient and creative.
Some of
these techniques in the past include cover jamming, where the target aims to
create "noise" wavelengths, to obscure or disrupt the returning
signal to the radar, such that the target's location is harder to acquire or
track. Another technique used is barrage jamming, where jamming signals, are
sent throughout numerous frequencies simultaneously, with the aim of trying to
cover any used frequencies (Adamy, 2010).
The
techniques used to jam radars has changed with more creative methods and better
jammers, rather than to impede, now aim to deceive the enemy radar by sending
false signals. One such technique, the range gate pull-off uses a jammer which receives
radar signals, replicates it and return it with greater strength but with a
longer time gap in between, in order to deceive the position of an object to
the radar (Adamy, 2010).
Moving
forward, the scope of jamming equipment now can be easily applied to most other
devices which use electromagnetic waves, such as cell phones (Silva, 2007).
Thus, the effects of jamming technology might still remain an issue, as the
impact of the interference of our daily lives now is huge.
3.3 Wireless
Technologies
Wireless
refers to the telecommunications without any wires, where electromagnetic waves
are used to transmit signals to other devices. The telecommunication industry
is worth one trillion US dollars, with 1 billion mobile phone users as of 2003
(Karlson, 2003). This shows us the impact of wireless technology in the
starting phases of the widespread adoption of such technology, and how it has
changed our lifestyles, for example 20 billion SMS messages are sent daily as
compared to the start of the mobile phone industry from 1978 (Karlson, 2003).
This figure is set to increase, whereby seven trillion wireless devices would
be used by seven billion people, by the year 2017 (Fitzek & Katz, 2007).
The current
level of development of wireless networks in our society is at the 4th generation
or 4G for short. This level of development is defined as have advanced high
performance wireless communications system, which are integrative, and are able
to cover most, if not all aspects of communications (Fitzek & Katz, 2007).
The type of wireless technology which is most commonly ultilised now are the
short-range wireless technologies, which consists of wireless local area networks(WLAN), wireless
personal area networks (WPAN), wireless body area networks (WBAN), wireless
sensor networks (WSN), car–to–car communications (C2C), Radio Frequency
Identification (RFID) and Near Field Communications (NFC) (Fitzek & Katz,
2007). These technologies are integrated into devices which we carry around,
which are usually connected to others which we hold, thus turning them clusters
to interact with other networks (Fitzek & Katz, 2007).
Wireless technologies
are now able to perform a variety of functions; wireless sensor networks are
used in harsh terrains, such as volcanoes and glaciers, where it can also be utilised
successfully in hospitals (Gaura et al, 2010).
The
Scalable Medical Alert and Response Technology (SMART) system was deployed in Brigham
and Women's Hospital’s Emergency Department in Boston for eighteen months, from
June, 2006, to December, 2007, monitoring 172 patients in total (Gaura et al,
2010). The system consists of four parts, the patient monitoring subsystem, the
central computer, the caregiver subsystem, and the location subsystem, where
the monitoring system will detect changes to the patient, send it to the
central system, then send the location and alarm to the caregivers closest to
the patient (Gaura et al, 2010).
The
increased application of wireless technology would continue to be a large part of
our lives, as the technology aims to improve and integrate all aspects of our
lives into a connected one.
4. Future Applications
Electromagnetics
is an integral part of our lives, where the technology has revolutionised the
way we are living as compared to 2 centuries ago. The field still has much
potential which remains to be explored, despite the significant contributions
and advances in the field.
4.1 Electromagnetic
Railguns
Electromagnetic
railguns is not a new concept, as the theory which acts behind it and the
designs for the railguns have been around for more than a century (Bajkov,
2013). The first recorded railgun tests were conducted during 1944- 1945 during
world war 2 by the Germans, under Joachim Hänsler in a railway tunnel near the town of Klais in
Upper Bavaria (Bajkov, 2013). The tests proved to be fruitful, as the prototype
was able to accelerate a 10 grams aluminium cylinder to 1,080 m/s, as compared
to the best anti-aircraft gun of the Germans which was only able to reach 880
m/s (Bajkov, 2013).
The
principle behind electromagnetic railguns is to use electric currents to
generate a magnetic field, which will in turn help to accelerate the shell
within the railgun, instead of gunpowder in traditional firearms (Lee, 2012).
The technology now is able to reach a range of up to 100 miles, as compared to
5 inch guns on destroyers which can only reach 15 miles (Lee, 2012). As for
speed, the railgun is able to reach 5,637 mph, which is seven times the speed
of sound, an improvement as compared to the speed of naval shells of 2000 mph
(Lee, 2012).
Figure 4 depicting
“How a railgun works” reproduced from LEE, M. (2012).
The
prototype testing results have been successful; however, there still remains
many limitations before this technology can become a reality. Currently, the railgun
is cannot be fired rapidly, and the ammunition also disintegrates during the
firing process (Lee, 2012). This is due to huge forces generated during the
firing of the railgun, where the heat from the acceleration causes the
ammunition to expand, and damages the rail, the recoil from the firing also
causes the rail to be split, and after firing the friction of the shells with
the air at high speeds would cause disintegration (Bajkov, 2013).
4.2 Wireless
Charging Roads
Wireless
charging, or inductive charging to be more accurate, which works on magnetic
resonance coupling, where two copper coils are tuned to resonate at a
frequency, one coil is then subjected to electric currents, which creates a
magnetic field to resonate with the other coil, resulting in the transfer of
energy (SHWARTZ, 2013).
This
technology is currently being adopted for charging of smaller objects, such as
mobile phones, whereas, for transportation roads with the same properties are
being built in Korea, Germany, Netherlands and Italy for public transport, such
as buses (BARRY, 2013). The application of these roads has been successful, as
technology has improved to allow the 85% power efficiency when charging at 100
kW, with a space of 6.7 inch between the bus and the road (BARRY, 2013).
Figure 5 depicting
“Wireless charging buses and roads in South Korea” reproduced from BARRY, K. (2013).
However, to
implement this smoothly, there are still obstacles on the way. The roads do not
give full power efficiency, so there is still the risk of the lost power being
converted into radiation, which might be harmful (SHWARTZ, 2013). Another
obstacle would be the costs taken to implement this technology, as this would
require entire highways to be overhauled, which might not be as practical in
the end (Kelion, 2013).
5 Future Implications
Electromagnetics
has revolutionised many industries, and have many impacts on our lives, some
desirable and some which should be reduced or contained.
5.1 Positive
Implications
5.1.1 Lowering
Accident Rates
The advent
of better wireless technologies has changed the way our devices interacted with
one another; this gives rise to the possibility of incorporation into other
fields to make our devices “smarter” (Pierce, 2011).
Due to
this, car to car communication has been developed on vehicles, as a method to
reduce road risks significantly (Pierce, 2011). This technology is incorporated
heavily in autonomous driving, where cars are linked and send information to
one another, allowing cars to avoid collision, detect obstacles ahead of time
and move away earlier (Pierce, 2011).
When this
technology is implemented within vehicles, it would help to increase our road
safety significantly, as it would reduce the amount of risky road behaviours,
such as drink driving, speeding, and resulting in lower accident rates all
around (Pierce, 2011).
Another of
such technology, which has worked well in ensuring safety, would be radar
technology (Woodhouse, 2012). Due to the implementation in various air craft
and ships, the chance of collisions has been reduced significantly, as they are
now able to detect obstacles ahead of time, and avoid each other.
5.1.2 Increased
Efficiency
The
wireless induction technology brings several advantages, as it helps to solve
the problem of limited battery capacity on electric cars, as electric cars like
Nissan Leaf, takes a long time to get charged while getting less than 100 miles
on that, so there is no need to run out of power, since you are charging while
driving (SHWARTZ, 2013). Another
advantage would be a smaller battery would be required, this would help to
bring down the weight of the vehicles, and make them more efficient, where
buses only use one thirds of a car's battery in the system (BARRY, 2013).
As
discussed above, maglev technology implemented in various fields have the
possibility of becoming more efficient, due to the ability to reduce surface
contact between 2 objects, resulting in less friction, so less energy is lost
as heat to the surroundings. Thus the technology is now more energy efficient,
the decrease in friction would also lead to a decrease in wear and tear, so
maintenance costs are lowered, making machines more efficient (Yaghoubi, 2013).
5.2 Negative
Implications
5.2.1 Addiction
from Wireless Technologies
Due to the
rise of telecommunications, the position of these technologies is getting
higher, and the roles they play in our lives are more important. Thus the amount
of time we spend on them has increased exponentially over the years, as
telecommunication networks become more advanced, though more and more people
are spending a disproportionate time on them, and becoming addicted at the end.
Currently
in South Korea, young teenagers aged between 9 to 12 have an internet addiction
rate of 14% (Lee, 2011). Due to the difficulty of identifying and curing such
addiction, adding to the increased integration of telecommunication technology
in our lives, the rate of addiction in the populace will continue to rise, as
the current young grows up and a new breed of youngsters would undergo the same
culture and subsequently end up addicted too.
Thus, the
South Korean government has tried to curb the problem by imposing a
"shutdown" law, blocking online games for children under sixteen
after midnight (Lee, 2011). This would possibly help to reduce in their young,
and help to reduce the addiction rates by limiting the time they could spend on
their computers. However, parents have spoken against the regulation, forcing
the government to relax the regulation, where children under eighteen with the
approval of their parents could set their own time limits (Kang, 2012). This
move has shown the emphasis of parent's role in their children's education and
formative years, to prevent such habits from forming, as children could just
bypass this regulation using their parent's information (Kang, 2012).
5.2.2 Health and
Safety Risks
Every
technology which we have in our daily lives, such as mobile phones, televisions
and computers, generate electromagnetic fields of different strengths, which could
affect our body in a harmful manner (Fahmy et al, 2013).
The fields
affect our health in various ways, such as severe headache, tumour, brain
cancer, sleep interference, allergic reactions, heart disease, infertility and
Alzheimer's disease (Fahmy et al, 2013). Electromagnetic radiation has a
negative effect on cells, and would affect embryos more strongly, resulting in
different degrees of cellular damage at the various stages of development, with
more serious effects at the early stages (Fahmy et al, 2013).
A study has
shown that women staying in urban areas, which are better educated and not
working end up having pregnancy related problems, due to their wider exposure
to electromagnetic radiation, by their environment and their usage of the
technologies (Fahmy et al, 2013).
5.2.3 Geo-Political
Implications From Military Development
Technology
is a cat and mouse game, especially in vital technologies which give a key
advantage in survival; this is especially true in the military sector, as at
this age, the level of technology one's military has could determine the
outcome of a war.
Thus, when
the world saw the nuclear bombs being fired at Nagasaki and Hiroshima for the
first time, it has lead to an arms race between the superpowers, America and
the USSR which lasted throughout the whole cold war period. Terms such as
mutually assured destruction (MAD), the ability for the 2 powers to potentially
destroy the world, has defined geo-political relations at that era, where the
two powers kept their conflicts to proxy wars, where they merely supplied and
attempted to influence developing countries, or tried to outdo one another in
terms of advancements such as space exploration.
The sheer
threat of such a technology has also defined global politics; where countries
attempt to create nuclear bombs, such as North Korea, often have high
geo-political tensions when they attempt testing for the technology, as
compared to South Korea which does not have the technology.
Similarly,
the invention and practical use of the railgun could in many cases become a
huge military threat which could affect geo-political relations, as it has the
ability to increase the range of all of a country's weaponry significantly,
making those who possess the technology a big threat to their rivals, or
countries which they are not on good relations with (Lee, 2012).
6. Conclusion
Electromagnetics
has brought significant benefits to humanity, by allowing world communication,
and has been a significant driver in shaping our world today. The theories
behind electromagnetics are still relevant, and are still being applied
currently with the aim of making our technology more efficient and
environmentally friendly.
Technology
for the field has been applied onto virtually every single industry in our
world, and is part of our lifestyles, despite the flaws and risks which come
with utilising these technologies.
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