- Electrical engineering
Electrical engineering, sometimes referred to as electrical and electronic engineering, is a field of
engineeringthat deals with the study and application of electricity, electronicsand electromagnetism. The field first became an identifiable occupation in the late nineteenth century after commercialization of the electric telegraphand electrical power supply. It now covers a range of subtopics including power, electronics, control systems, signal processingand telecommunications.
Electrical engineering may or may not include
electronic engineering. Where a distinction is made, usually outside of the United States, electrical engineering is considered to deal with the problems associated with large-scale electrical systems such as power transmission and motor control, whereas electronic engineering deals with the study of small-scale electronic systems including computersand integrated circuits. [cite web | title = What is the difference between electrical and electronic engineering? | work = FAQs - Studying Electrical Engineering | url = http://www.ieee.org/organizations/eab/faqs1.htm | accessmonthday = 4 February | accessyear = 2005 ] Alternatively, electrical engineers are usually concerned with using electricity to transmit energy, while electronic engineers are concerned with using electricity to transmit information.
Electricityhas been a subject of scientific interest since at least the early 17th century. The first electrical engineer was probably William Gilbertwho designed the versorium: a device that detected the presence of statically charged objects. He was also the first to draw a clear distinction between magnetism and static electricity and is credited with establishing the term electricity. [cite web | title = William Gilbert (1544–1603) | work = Pioneers in Electricity | url = http://www.magnet.fsu.edu/education/tutorials/pioneers/gilbert.html | accessmonthday = 13 May | accessyear = 2007 ] In 1775 Alessandro Volta's scientific experimentations devised the electrophorus, a device that produced a static electric charge, and by 1800 Volta developed the voltaic pile, a forerunner of the electric battery. [Vaunt Design Group. (2005). [http://www.ideafinder.com/history/inventors/volta.htm "Inventor Alessandro Volta Biography."] Troy MI: The Great Idea Finder. Accessed 21 March 2008.]
However, it was not until the 19th century that research into the subject started to intensify. Notable developments in this century include the work of
Georg Ohm, who in 1827 quantified the relationship between the electric currentand potential differencein a conductor, Michael Faraday, the discoverer of electromagnetic inductionin 1831, and James Clerk Maxwell, who in 1873 published a unified theory of electricity and magnetismin his treatise "Electricity and Magnetism". [cite encyclopedia| ency = Encyclopedia Britannica | edition = 11 | year = 1911 | article = "Ohm, Georg Simon", "Faraday, Michael" and "Maxwell, James Clerk"]
During these years, the study of electricity was largely considered to be a subfield of
physics. It was not until the late 19th century that universities started to offer degrees in electrical engineering. The Darmstadt University of Technologyfounded the first chair and the first faculty of electrical engineering worldwide in 1882. In 1883 Darmstadt University of Technologyand Cornell Universityintroduced the world's first courses of study in electrical engineering, and in 1885 the University College Londonfounded the first chair of electrical engineering in the United Kingdom. [cite web | title = Welcome to ECE! | work = Cornell University - School of Electrical and Computer Engineering | url = http://www.ece.cornell.edu | accessmonthday = 29 December | accessyear = 2005 ] The University of Missourisubsequently established the first department of electrical engineering in the United States in 1886. [cite book | author = Ryder, John and Fink, Donald; | title = Engineers and Electrons | publisher = IEEE Press | year = 1984 | id = ISBN 0-87942-172-X ]
During this period, the work concerning electrical engineering increased dramatically. In 1882, Edison switched on the world's first large-scale electrical supply network that provided 110 volts
direct currentto fifty-nine customers in lower Manhattan. In 1887, Nikola Teslafiled a number of patents related to a competing form of power distribution known as alternating current. In the following years a bitter rivalry between Tesla and Edison, known as the " War of Currents", took place over the preferred method of distribution. AC eventually replaced DC for generation and power distribution, enormously extending the range and improving the safety and efficiency of power distribution.
The efforts of the two did much to further electrical engineering—Tesla's work on
induction motors and polyphase systems influenced the field for years to come, while Edison's work on telegraphy and his development of the stock tickerproved lucrative for his company, which ultimately became General Electric. However, by the end of the 19th century, other key figures in the progress of electrical engineering were beginning to emerge. [cite web | title = History | work = National Fire Protection Association (NFPA) | url = http://www.nfpa.org/itemDetail.asp?categoryID=500&itemID=18020&URL=About%20Us/History | accessmonthday = 19 January | accessyear = 2006 "(published 1996 in the NFPA Journal)"]
; Emergence of radio and electronicsDuring the development of radio, many scientists and
inventors contributed to radio technology and electronics. In his classic UHF experiments of 1888, Heinrich Hertztransmitted (via a spark-gap transmitter) and detected radio wavesusing electrical equipment. In 1895, Nikola Tesla was able to detect signals from the transmissions of his New York lab at West Point (a distance of 80.4 km / 49.95 miles). [Leland Anderson, "Nikola Tesla On His Work With Alternating Currents and Their Application to Wireless Telegraphy, Telephony, and Transmission of Power", Sun Publishing Company, LC 92-60482, ISBN 0-9632652-0-2 ("ed". [http://www.tfcbooks.com/tesla/nt_on_ac.htm excerpts available online] )] In 1897, Karl Ferdinand Braunintroduced the cathode ray tubeas part of an oscilloscope, a crucial enabling technology for electronic television. [cite web | title = Karl Ferdinand Braun | url = http://nobelprize.org/nobel_prizes/physics/laureates/1909/braun-bio.html | accessmonthday = 10 September | accessyear = 2006 ] John Fleming invented the first radio tube, the diode, in 1904. Two years later, Robert von Liebenand Lee De Forestindependently developed the amplifier tube, called the triode. [cite web | title = History of Amateur Radio | work = What is Amateur Radio? | url = http://www.amateurradio.uni-halle.de/hamradio.en.html | accessmonthday = 18 January | accessyear = 2006 ] In 1895, Guglielmo Marconifurthered the art of hertzian wireless methods. Early on, he sent wireless signals over a distance of one and a half miles. In December 1901, he sent wireless waves that were not affected by the curvature of the Earth. Marconi later transmitted the wireless signals across the Atlantic between Poldhu, Cornwall, and St. John's, Newfoundland, a distance of convert|2100|mi|km. [ [http://nobelprize.org/nobel_prizes/physics/laureates/1909/marconi-bio.html Marconi's biography at Nobelprize.org] retrieved 21 June 2008.] In 1920 Albert Hulldeveloped the magnetron which would eventually lead to the development of the microwave ovenin 1946 by Percy Spencer. [cite web | title = Albert W. Hull (1880–1966) | work = IEEE History Center | url = http://www.ieee.org/organizations/history_center/legacies/hull.html | accessmonthday = 22 January | accessyear = 2006 ] [cite web | title = Who Invented Microwaves? | url = http://www.gallawa.com/microtech/history.html | accessmonthday = 22 January | accessyear = 2006 ] In 1934 the British military began to make strides towards radar(which also uses the magnetron) under the direction of Dr Wimperis, culminating in the operation of the first radar station at Bawdseyin August 1936. [cite web | title = Early Radar History | work = Peneley Radar Archives | url = http://www.penleyradararchives.org.uk/history/introduction.htm | accessmonthday = 22 January | accessyear = 2006 ]
Konrad Zusepresented the Z3, the world's first fully functional and programmable computer. [cite web | title = The Z3 | url = http://irb.cs.tu-berlin.de/~zuse/Konrad_Zuse/en/Rechner_Z3.html | accessmonthday = 18 January | accessyear = 2006 ] In 1946 the ENIAC(Electronic Numerical Integrator and Computer) of John Presper Eckertand John Mauchlyfollowed, beginning the computing era. The arithmetic performance of these machines allowed engineers to develop completely new technologies and achieve new objectives, including the Apollo missions and the NASA moon landing. [cite web | title = The ENIAC Museum Online | url = http://www.seas.upenn.edu/~museum/guys.html | accessmonthday = 18 January | accessyear = 2006 ]
The invention of the transistor in 1947 by
William B. Shockley, John Bardeenand Walter Brattainopened the door for more compact devices and led to the development of the integrated circuitin 1958 by Jack Kilbyand independently in 1959 by Robert Noyce. [cite web | title = Electronics Timeline | work = Greatest Engineering Achievements of the Twentieth Century | url = http://www.greatachievements.org/?id=3956 | accessmonthday = 18 January | accessyear = 2006 ] In 1968 Marcian Hoffinvented the first microprocessorat Inteland thus ignited the development of the personal computer. The first realization of the microprocessor was the Intel 4004, a 4-bit processor developed in 1971, but only in 1973 did the Intel 8080, an 8-bit processor, make the building of the first personal computer, the Altair 8800, possible. [cite web | title = Computing History (1971–1975) | url = http://mbinfo.mbdesign.net/1971-75.htm | accessmonthday = 18 January | accessyear = 2006 ]
Electrical engineers typically possess an
academic degreewith a major in electrical engineering. The length of study for such a degree is usually four or five years and the completed degree may be designated as a Bachelor of Engineering, Bachelor of Science, Bachelor of Technologyor Bachelor of Applied Sciencedepending upon the university. The degree generally includes units covering physics, mathematics, computer science, project managementand specific topics in electrical engineering. Initially such topics cover most, if not all, of the sub-disciplines of electrical engineering. Students then choose to specialize in one or more sub-disciplines towards the end of the degree.
Some electrical engineers also choose to pursue a postgraduate degree such as a
Master of Engineering/ Master of Science(MEng/MSc), a Master of Engineering Management, a Doctor of Philosophy(PhD) in Engineering, an Engineering Doctorate(EngD), or an Engineer's degree. The Master and Engineer's degree may consist of either research, courseworkor a mixture of the two. The Doctor of Philosophy and Engineering Doctorate degrees consist of a significant research component and are often viewed as the entry point to academia. In the United Kingdom and various other European countries, the Master of Engineeringis often considered an undergraduate degree of slightly longer duration than the Bachelor of Engineering. [Various including graduate degree requirements [http://www.eecs.mit.edu/grad/degrees.html at MIT] , study guide [http://www.ecm.uwa.edu.au/study_guides/2007/be_bcompsc/ee at UWA] , the curriculum [http://www.queensu.ca/calendars/appsci/pg174.html at Queen's] and unit tables [http://www.abdn.ac.uk/registry/calendar/requirements/07H50116.doc at Aberdeen] ]
In most countries, a Bachelor's degree in engineering represents the first step towards
professional certificationand the degree program itself is certified by a professional body. After completing a certified degree program the engineer must satisfy a range of requirements (including work experience requirements) before being certified. Once certified the engineer is designated the title of Professional Engineer(in the United States, Canada and South Africa ), Chartered Engineer(in India, the United Kingdom, Ireland and Zimbabwe), Chartered Professional Engineer(in Australia and New Zealand) or European Engineer(in much of the European Union).
The advantages of certification vary depending upon location. For example, in the United States and Canada "only a licensed engineer may seal engineering work for public and private clients". [cite web | title = Why Should You Get Licensed? | work = National Society of Professional Engineers | url = http://www.nspe.org/lc1-why.asp | accessmonthday = 11 July | accessyear = 2005 ] This requirement is enforced by state and provincial legislation such as Quebec's Engineers Act. [cite web | title = Engineers Act | work = Quebec Statutes and Regulations (CanLII) | url = http://www.canlii.org/qc/laws/sta/i-9/20050616/whole.html | accessmonthday = 24 July | accessyear = 2005 ] In other countries, such as Australia, no such legislation exists to practise engineering, however it is a mandate that if an engineer is to sign off or seal an engineering document or drawing then that person must be registered as a Certified Practising Engineer (or CPEng). [cite web | title = Professional Engineers - Application | work = Engineers Australia | url = http://www.engineersaustralia.org.au/nerb/applying/professional-engineers.cfm | accessmonthday = 28 September | accessyear = 2008 ] Practically all certifying bodies maintain a
code of ethicsthat they expect all members to abide by or risk expulsion. [cite web | title = Codes of Ethics and Conduct | work = Online Ethics Center | url = http://onlineethics.org/CMS/profpractice/ethcodes.aspx | accessmonthday = 24 July | accessyear = 2005 ] In this way these organizations play an important role in maintaining ethical standards for the profession. Even in jurisdictions where certification has little or no legal bearing on work, engineers are subject to contract law. In cases where an engineer's work fails he or she may be subject to the tort of negligence and, in extreme cases, the charge of criminal negligence. An engineer's work must also comply with numerous other rules and regulations such as building codesand legislation pertaining to environmental law.
Professional bodies of note for electrical engineers include the
Institute of Electrical and Electronics Engineers(IEEE) and the Institution of Engineering and Technology(IET) (which was formed by the merging of the Institution of Electrical Engineers(IEE) and the Institution of Incorporated Engineers(IIE). The IEEE claims to produce 30% of the world's literature in electrical engineering, has over 360,000 members worldwide and holds over 3,000 conferences annually. [cite web | title = About the IEEE | work = IEEE | url = http://www.ieee.org/about/ | accessmonthday = 11 July | accessyear = 2005 ] The IET publishes 21 journals, has a worldwide membership of over 150,000, and claims to be the largest professional engineering society in Europe. [cite web | title = About the IET | work = The IET | url = http://www.theiet.org/about/ | accessmonthday = 11 July | accessyear = 2005 ] [cite web | title = Journal and Magazines | work = The IET | url = http://www.theiet.org/publishing/journals/ | accessmonthday = 11 July | accessyear = 2005 ] Obsolescence of technical skills is a serious concern for electrical engineers. Membership and participation in technical societies, regular reviews of periodicals in the field and a habit of continued learning are therefore essential to maintaining proficiency. [cite web | title = Electrical and Electronics Engineers, except Computer | work = Occupational Outlook Handbook | url = http://www.bls.gov/oco/ocos031.htm | accessmonthday = 16 July | accessyear = 2005 (see here regarding copyright)]
In countries such as Australia, Canada and the United States electrical engineers make up around 0.25% of the labor force (see note). Outside of these countries, it is difficult to gauge the demographics of the profession due to less meticulous reporting on labor statistics. However, in terms of electrical engineering graduates per-capita, electrical engineering graduates would probably be most numerous in countries such as
Taiwan, Japan, India and South Korea. [cite web | publisher = National Science Foundation | year = 2004 | url = http://www.nsf.gov/statistics/seind04/append/c2/at02-33.pdf | title = Science and Engineering Indicators 2004, Appendix 2-33 | format = PDF ]
Tools and work
Global Positioning Systemto electric power generation, electrical engineers have contributed to the development of a wide range of technologies. They design, develop, test and supervise the deployment of electrical systems and electronic devices. For example, they may work on the design of telecommunication systems, the operation of electric power stations, the lightingand wiring of buildings, the design of household appliances or the electrical control of industrial machinery. [cite web | title = Electrical and Electronics Engineers, except Computer | work = Occupational Outlook Handbook | url = http://www.bls.gov/oco/ocos031.htm | accessmonthday = 16 July | accessyear = 2005 (see [http://web.archive.org/web/www.bls.gov/oco/ocos031.htm Internet Archive] )]
Fundamental to the discipline are the sciences of
physicsand mathematicsas these help to obtain both a qualitativeand quantitativedescription of how such systems will work. Today most engineeringwork involves the use of computersand it is commonplace to use computer-aided designprograms when designing electrical systems. Nevertheless, the ability to sketch ideas is still invaluable for quickly communicating with others.
Although most electrical engineers will understand basic
circuit theory(that is the interactions of elements such as resistors, capacitors, diodes, transistorsand inductorsin a circuit), the theories employed by engineers generally depend upon the work they do. For example, quantum mechanicsand solid state physicsmight be relevant to an engineer working on VLSI(the design of integrated circuits), but are largely irrelevant to engineers working with macroscopic electrical systems. Even circuit theorymay not be relevant to a person designing telecommunication systems that use off-the-shelf components. Perhaps the most important technical skills for electrical engineers are reflected in university programs, which emphasize strong numerical skills, computer literacyand the ability to understand the technical language and concepts that relate to electrical engineering.
For many engineers, technical work accounts for only a fraction of the work they do. A lot of time may also be spent on tasks such as discussing proposals with clients, preparing
budgets and determining project schedules. [Trevelyan, James; (2005). "What Do Engineers Really Do?". University of Western Australia. (seminar with [http://www.mech.uwa.edu.au/jpt/Engineering%20Roles%20050503.pdf slides] )] Many senior engineers manage a team of technicians or other engineers and for this reason project managementskills are important. Most engineering projects involve some form of documentation and strong written communication skills are therefore very important.
The workplaces of electrical engineers are just as varied as the types of work they do. Electrical engineers may be found in the pristine lab environment of a
fabrication plant, the offices of a consulting firmor on site at a mine. During their working life, electrical engineers may find themselves supervising a wide range of individuals including scientists, electricians, computer programmersand other engineers.
Electrical engineering has many sub-disciplines, the most popular of which are listed below. Although there are electrical engineers who focus exclusively on one of these sub-disciplines, many deal with a combination of them. Sometimes certain fields, such as electronic engineering and computer engineering, are considered separate disciplines in their own right.
Power engineeringdeals with the generation, transmission and distribution of electricityas well as the design of a range of related devices. These include transformers, electric generators, electric motors, high voltage engineering and power electronics. In many regions of the world, governments maintain an electrical network called a power gridthat connects a variety of generators together with users of their energy. Users purchase electrical energy from the grid, avoiding the costly exercise of having to generate their own. Power engineers may work on the design and maintenance of the power grid as well as the power systems that connect to it. Such systems are called "on-grid" power systems and may supply the grid with additional power, draw power from the grid or do both. Power engineers may also work on systems that do not connect to the grid, called "off-grid" power systems, which in some cases are preferable to on-grid systems. The future includes Satellite controlled power systems, with feedback in real time to prevent power surges and prevent blackouts.
Control engineeringfocuses on the modeling of a diverse range of dynamic systems and the design of controllers that will cause these systems to behave in the desired manner. To implement such controllers electrical engineers may use electrical circuits, digital signal processors, microcontrollers and PLCs (Programmable Logic Controllers). Control engineeringhas a wide range of applications from the flight and propulsion systems of commercial airliners to the cruise controlpresent in many modern automobiles. It also plays an important role in industrial automation.
Control engineers often utilize
feedbackwhen designing control systems. For example, in an automobilewith cruise controlthe vehicle's speedis continuously monitored and fed back to the system which adjusts the motor's power outputaccordingly. Where there is regular feedback, control theorycan be used to determine how the system responds to such feedback.
Electronic engineeringinvolves the design and testing of electronic circuits that use the properties of components such as resistors, capacitors, inductors, diodes and transistors to achieve a particular functionality. The tuned circuit, which allows the user of a radioto filter out all but a single station, is just one example of such a circuit. Another example (of a pneumatic signal conditioner) is shown in the adjacent photograph.
Prior to the second world war, the subject was commonly known as "radio engineering" and basically was restricted to aspects of communications and
radar, commercial radio and early television. Later, in post war years, as consumer devices began to be developed, the field grew to include modern television, audio systems, computers and microprocessors. In the mid to late 1950s, the term "radio engineering" gradually gave way to the name "electronic engineering".
Before the invention of the
integrated circuitin 1959, electronic circuits were constructed from discrete components that could be manipulated by humans. These discrete circuits consumed much space and power and were limited in speed, although they are still common in some applications. By contrast, integrated circuits packed a large number—often millions—of tiny electrical components, mainly transistors, into a small chip around the size of a coin. This allowed for the powerful computers and other electronic devices we see today.
Microelectronicsengineering deals with the design and microfabricationof very small electronic circuit components for use in an integrated circuitor sometimes for use on their own as a general electronic component. The most common microelectronic components are semiconductor transistors, although all main electronic components ( resistors, capacitors, inductors) can be created at a microscopic level.
Microelectronic components are created by chemically fabricating wafers of semiconductors such as silicon (at higher frequencies,
compound semiconductors like gallium arsenide and indium phosphide) to obtain the desired transport of electronic charge and control of current. The field of microelectronics involves a significant amount of chemistry and material science and requires the electronic engineer working in the field to have a very good working knowledge of the effects of quantum mechanics.
Signal processingdeals with the analysis and manipulations of signals. Signals can be either analog, in which case the signal varies continuously according to the information, or digital, in which case the signal varies according to a series of discrete values representing the information. For analog signals, signal processing may involve the amplification and filtering of audio signals for audio equipment or the modulationand demodulationof signals for telecommunications. For digital signals, signal processing may involve the compression, error detectionand error correctionof digitally sampled signals.
Telecommunications engineering focuses on the transmission of
informationacross a channel such as a coax cable, optical fiberor free space. Transmissions across free space require information to be encoded in a carrier wavein order to shift the information to a carrier frequencysuitable for transmission, this is known as modulation. Popular analog modulation techniques include amplitude modulationand frequency modulation. The choice of modulation affects the cost and performance of a system and these two factors must be balanced carefully by the engineer.
Once the transmission characteristics of a system are determined, telecommunication engineers design the
transmitters and receivers needed for such systems. These two are sometimes combined to form a two-way communication device known as a transceiver. A key consideration in the design of transmitters is their power consumptionas this is closely related to their signal strength. If the signal strength of a transmitter is insufficient the signal's information will be corrupted by noise.
Instrumentation engineeringdeals with the design of devices to measure physical quantities such as pressure, flowand temperature. The design of such instrumentation requires a good understanding of physicsthat often extends beyond electromagnetic theory. For example, radar guns use the Doppler effectto measure the speed of oncoming vehicles. Similarly, thermocouples use the Peltier-Seebeck effectto measure the temperature difference between two points.
Often instrumentation is not used by itself, but instead as the
sensors of larger electrical systems. For example, a thermocouple might be used to help ensure a furnace's temperature remains constant. For this reason, instrumentation engineering is often viewed as the counterpart of control engineering.
Computer engineeringdeals with the design of computers and computer systems. This may involve the design of new hardware, the design of PDAs or the use of computers to control an industrial plant. Computer engineers may also work on a system's software. However, the design of complex software systems is often the domain of software engineering, which is usually considered a separate discipline. Desktop computers represent a tiny fraction of the devices a computer engineer might work on, as computer-like architectures are now found in a range of devices including video game consoles and DVD players.
Mechatronicsis an engineering discipline which deals with the convergence of electrical and mechanical systems. Such combined systems are known as electromechanicalsystems and have widespread adoption. Examples include automated manufacturing systems, heating, ventilation and air-conditioning systems and various subsystems of aircraftand automobiles.
The term "mechatronics" is typically used to refer to
macroscopicsystems but futurists have predicted the emergence of very small electromechanical devices. Already such small devices, known as micro electromechanical systems (MEMS), are used in automobiles to tell airbags when to deploy, in digital projectors to create sharper images and in inkjet printers to create nozzles for high definition printing. In the future it is hoped the devices will help build tiny implantable medical devices and improve optical communication. [cite web | title = MEMS the world! | work = IntelliSense Software Corporation | url = http://www.intellisensesoftware.com/Technology.html | accessmonthday = 17 July | accessyear = 2005 ] Biomedical engineeringis another related discipline, concerned with the design of medical equipment. This includes fixed equipment such as ventilators, MRI scanners and electrocardiograph monitors as well as mobile equipment such as cochlear implants, artificial pacemakers and artificial hearts.
Analog signal processing
Electronic design automation
Institution of Engineering and Technology(IET)
*List of electrical engineering topics (alphabetical)
List of electrical engineering topics(thematic)
List of electrical engineers
ReferencesNotes:Note I - There are around 370,000 people working as computer hardware or electrical engineers in the United States constituting 0.24% of the labor force (2006). [cite web | title=Electrical Engineers | publisher=
Bureau of Labor Statistics| url=http://www.bls.gov/oco/ocos027.htm | accessdate=2008-06-20 ] [cite web | title=Work Experience of the Population in 2006 | publisher= Bureau of Labor Statistics| url=http://www.bls.gov/news.release/History/work_12192007.txt | accessdate=2008-06-20 ] In Australia, there are around 24,000 constituting 0.23% of the labour force (2005) and in Canada, there are around 34,600 constituting 0.21% of the labour force (2001). Australia and Canada also report that 96% and 89% of their electrical engineers respectively are male. [cite web | title = Electrical and Electronics Engineers | work = Australian Careers | url = http://jobsearch.gov.au/joboutlook/default.aspx?PageId=AscoDesc&AscoCode=2125 | accessmonthday = 27 August | accessyear = 2005 ] [cite web | title = Electrical and Electronics Engineers (NOC 2133) | work = Job Futures (National Edition) | url = http://www.jobfutures.ca/noc/2133p1.shtml | accessmonthday = 27 August | accessyear = 2005 ]
* [http://www.ieee-virtual-museum.org/ IEEE Virtual Museum] A virtual museum that illustrates many of the basic electrical engineering and electricity concepts through examples, figures, and interviews.
* [http://ocw.mit.edu/OcwWeb/Electrical-Engineering-and-Computer-Science/index.htm MIT OpenCourseWare] In-depth look at Electrical Engineering with online courses featuring video lectures.
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