114-435: JCM may refer to: People [ edit ] James Clerk Maxwell (1831–1879), Scottish physicist John Cougar Mellencamp (born 1951), American singer Science and technology [ edit ] Japan Collection of Microorganisms Jaynes-Cummings model Journal of Clinical Microbiology Journal of Communications AGM-169 Joint Common Missile JunoCam ,
228-470: A mass-production basis, they opened the door for more compact devices. The first integrated circuits were the hybrid integrated circuit invented by Jack Kilby at Texas Instruments in 1958 and the monolithic integrated circuit chip invented by Robert Noyce at Fairchild Semiconductor in 1959. The MOSFET (metal–oxide–semiconductor field-effect transistor, or MOS transistor) was invented by Mohamed Atalla and Dawon Kahng at BTL in 1959. It
342-807: A professional body or an international standards organization. These include the International Electrotechnical Commission (IEC), the National Society of Professional Engineers (NSPE), the Institute of Electrical and Electronics Engineers (IEEE) and the Institution of Engineering and Technology (IET, formerly the IEE). Electrical engineers work in a very wide range of industries and the skills required are likewise variable. These range from circuit theory to
456-570: A Christian can actually purge his land of these holy spots. ... I do not say that no Christians have enclosed places of this sort. Many have a great deal, and every one has some. But there are extensive and important tracts in the territory of the Scoffer, the Pantheist, the Quietist, Formalist, Dogmatist, Sensualist, and the rest, which are openly and solemnly Tabooed. ..." Christianity—that is,
570-489: A camera on a planned space probe to the planet Jupiter Other uses [ edit ] Jewish Children's Museum Jackson Central-Merry High School , a public high school in Jackson, Tennessee Joint Council of Municipalities Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title JCM . If an internal link led you here, you may wish to change
684-412: A clear distinction between magnetism and static electricity . He is credited with establishing the term "electricity". He also designed the versorium : a device that detects the presence of statically charged objects. In 1762 Swedish professor Johan Wilcke invented a device later named electrophorus that produced a static electric charge. By 1800 Alessandro Volta had developed the voltaic pile ,
798-526: A degree is usually four or five years and the completed degree may be designated as a Bachelor of Science in Electrical/Electronics Engineering Technology, Bachelor of Engineering , Bachelor of Science, Bachelor of Technology , or Bachelor of Applied Science , depending on the university. The bachelor's degree generally includes units covering physics , mathematics, computer science , project management , and
912-415: A forerunner of the electric battery. In the 19th century, research into the subject started to intensify. Notable developments in this century include the work of Hans Christian Ørsted , who discovered in 1820 that an electric current produces a magnetic field that will deflect a compass needle; of William Sturgeon , who in 1825 invented the electromagnet ; of Joseph Henry and Edward Davy , who invented
1026-643: A general electronic component. The most common microelectronic components are semiconductor transistors , although all main electronic components ( resistors , capacitors etc.) can be created at a microscopic level. Nanoelectronics is the further scaling of devices down to nanometer levels. Modern devices are already in the nanometer regime, with below 100 nm processing having been standard since around 2002. 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
1140-459: A huge number of specializations including hardware engineering, power electronics , electromagnetics and waves, microwave engineering , nanotechnology , electrochemistry , renewable energies, mechatronics/control, and electrical materials science. Electrical engineers typically hold a degree in electrical engineering, electronic or electrical and electronic engineering. Practicing engineers may have professional certification and be members of
1254-407: 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. Microelectronics engineering deals with the design and microfabrication of very small electronic circuit components for use in an integrated circuit or sometimes for use on their own as
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#17327732469601368-521: A near-fatal bout of smallpox in 1860, he moved to London with his wife. Maxwell's time at King's was probably the most productive of his career. He was awarded the Royal Society's Rumford Medal in 1860 for his work on colour and was later elected to the Society in 1861. This period of his life would see him display the world's first light-fast colour photograph, further develop his ideas on
1482-400: A noise drew the question: "what's the go o' that?" In a passage added to a letter from his father to his sister-in-law Jane Cay in 1834, his mother described this innate sense of inquisitiveness: He is a very happy man, and has improved much since the weather got moderate; he has great work with doors, locks, keys, etc., and "show me how it doos" is never out of his mouth. He also investigates
1596-404: A partaker of Infinity. He strenuously works out his daily enterprises, because the present is given him for a possession. Electrical engineering Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems that use electricity , electronics , and electromagnetism . It emerged as an identifiable occupation in
1710-493: A plurality of foci" was presented to the Royal Society of Edinburgh by James Forbes , a professor of natural philosophy at the University of Edinburgh , because Maxwell was deemed too young to present the work himself. The work was not entirely original, since René Descartes had also examined the properties of such multifocal ellipses in the 17th century, but Maxwell had simplified their construction. Maxwell left
1824-505: A profession in the later 19th century. Practitioners had created a global electric telegraph network, and the first professional electrical engineering institutions were founded in the UK and the US to support the new discipline. Francis Ronalds created an electric telegraph system in 1816 and documented his vision of how the world could be transformed by electricity. Over 50 years later, he joined
1938-502: A similar age who were to become notable scholars later in life. They remained lifelong friends. Maxwell was fascinated by geometry at an early age, rediscovering the regular polyhedra before he received any formal instruction. Despite his winning the school's scripture biography prize in his second year, his academic work remained unnoticed until, at the age of 13, he won the school's mathematical medal and first prize for both English and poetry. Maxwell's interests ranged far beyond
2052-459: A strong contrast to the pallor of his complexion. He focused his attention on a problem that had eluded scientists for 200 years: the nature of Saturn's rings . It was unknown how they could remain stable without breaking up, drifting away or crashing into Saturn. The problem took on a particular resonance at that time because St John's College, Cambridge , had chosen it as the topic for the 1857 Adams Prize . Maxwell devoted two years to studying
2166-508: A strong respect for each other's talents. This time is especially noteworthy for the advances Maxwell made in the fields of electricity and magnetism. He examined the nature of both electric and magnetic fields in his two-part paper " On physical lines of force ", which was published in 1861. In it, he provided a conceptual model for electromagnetic induction , consisting of tiny spinning cells of magnetic flux . Two more parts were later added to and published in that same paper in early 1862. In
2280-426: A variety of industries. Electronic engineering involves 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 radio to filter out all but a single station, is just one example of such a circuit. Another example to research
2394-553: A week, including a weekly pro bono lecture to the local working men's college. He lived in Aberdeen with his cousin William Dyce Cay , a Scottish civil engineer, during the six months of the academic year and spent the summers at Glenlair, which he had inherited from his father. Later, his former student described Maxwell as follows: In the late 1850s shortly before 9 am any winter’s morning you might well have seen
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#17327732469602508-468: A year his senior. His mannerisms and Galloway accent struck the other boys as rustic. Having arrived on his first day of school wearing a pair of homemade shoes and a tunic, he earned the unkind nickname of " Daftie ". He never seemed to resent the epithet, bearing it without complaint for many years. Social isolation at the Academy ended when he met Lewis Campbell and Peter Guthrie Tait , two boys of
2622-455: Is a memorial inscription to him near the choir screen at Westminster Abbey . As a great lover of Scottish poetry , Maxwell memorised poems and wrote his own. The best known is Rigid Body Sings , closely based on " Comin' Through the Rye " by Robert Burns , which he apparently used to sing while accompanying himself on a guitar. It has the opening lines Gin a body meet a body Flyin' through
2736-470: Is a pneumatic signal conditioner. 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
2850-475: Is also known for presenting the first durable colour photograph in 1861 and for his foundational work on analysing the rigidity of rod-and-joint frameworks ( trusses ) like those in many bridges. Maxwell helped to established the CGS system of measurement. He is responsible for modern dimensional analysis . Maxwell is also recognized for laying the groundwork for chaos theory . Maxwell correctly predicted that
2964-444: Is an engineering discipline that deals with the convergence of electrical and mechanical systems. Such combined systems are known as electromechanical systems and have widespread adoption. Examples include automated manufacturing systems , heating, ventilation and air-conditioning systems , and various subsystems of aircraft and automobiles . Electronic systems design is the subject within electrical engineering that deals with
3078-798: Is still important in the design of many control systems . DSP processor ICs are found in many types of modern electronic devices, such as digital television sets , radios, hi-fi audio equipment, mobile phones, multimedia players , camcorders and digital cameras, automobile control systems, noise cancelling headphones, digital spectrum analyzers , missile guidance systems, radar systems, and telematics systems. In such products, DSP may be responsible for noise reduction , speech recognition or synthesis , encoding or decoding digital media, wirelessly transmitting or receiving data, triangulating positions using GPS , and other kinds of image processing , video processing , audio processing , and speech processing . Instrumentation engineering deals with
3192-461: Is their power consumption as this is closely related to their signal strength . Typically, if the power of the transmitted signal is insufficient once the signal arrives at the receiver's antenna(s), the information contained in the signal will be corrupted by noise , specifically static. Control engineering focuses on the modeling of a diverse range of dynamic systems and the design of controllers that will cause these systems to behave in
3306-567: Is very useful for energy transmission as well as for information transmission. These were also the first areas in which electrical engineering was developed. Today, electrical engineering has many subdisciplines, the most common of which are listed below. Although there are electrical engineers who focus exclusively on one of these subdisciplines, many deal with a combination of them. Sometimes, certain fields, such as electronic engineering and computer engineering , are considered disciplines in their own right. Power & Energy engineering deals with
3420-792: The Z3 , the world's first fully functional and programmable computer using electromechanical parts. In 1943, Tommy Flowers designed and built the Colossus , the world's first fully functional, electronic, digital and programmable computer. In 1946, the ENIAC (Electronic Numerical Integrator and Computer) of John Presper Eckert and John Mauchly followed, beginning the computing era. The arithmetic performance of these machines allowed engineers to develop completely new technologies and achieve new objectives. In 1948, Claude Shannon published "A Mathematical Theory of Communication" which mathematically describes
3534-548: The compression , error detection and error correction of digitally sampled signals. Signal processing is a very mathematically oriented and intensive area forming the core of digital signal processing and it is rapidly expanding with new applications in every field of electrical engineering such as communications, control, radar, audio engineering , broadcast engineering , power electronics, and biomedical engineering as many already existing analog systems are replaced with their digital counterparts. Analog signal processing
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3648-640: The density of the Earth and the composition of water. He was elected as a member to the American Philosophical Society in 1876. In April 1879 Maxwell began to have difficulty in swallowing, the first symptom of his fatal illness. Maxwell died in Cambridge of abdominal cancer on 5 November 1879 at the age of 48. His mother had died at the same age of the same type of cancer. The minister who regularly visited him in his last weeks
3762-658: The doubling of transistors on an IC chip every two years, predicted by Gordon Moore in 1965. Silicon-gate MOS technology was developed by Federico Faggin at Fairchild in 1968. Since then, the MOSFET has been the basic building block of modern electronics. The mass-production of silicon MOSFETs and MOS integrated circuit chips, along with continuous MOSFET scaling miniaturization at an exponential pace (as predicted by Moore's law ), has since led to revolutionary changes in technology, economy, culture and thinking. The Apollo program which culminated in landing astronauts on
3876-520: The electrical relay in 1835; of Georg Ohm , who in 1827 quantified the relationship between the electric current and potential difference in a conductor ; of Michael Faraday , the discoverer of electromagnetic induction in 1831; and of James Clerk Maxwell , who in 1873 published a unified theory of electricity and magnetism in his treatise Electricity and Magnetism . In 1782, Georges-Louis Le Sage developed and presented in Berlin probably
3990-452: The generation , transmission , and distribution of electricity as 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 grid that connects a variety of generators together with users of their energy. Users purchase electrical energy from
4104-480: The rings of Saturn were made up of many unattached small fragments. His 1863 paper On Governors serves as an important foundation for control theory and cybernetics , and was also the earliest mathematical analysis on control systems . His discoveries helped usher in the era of modern physics, laying the foundations for such fields as relativity , also being the one to introduce the term into physics, and quantum mechanics . Many physicists regard Maxwell as
4218-448: The transmission of information across a communication channel such as a coax cable , optical fiber or free space . Transmissions across free space require information to be encoded in a carrier signal to shift the information to a carrier frequency suitable for transmission; this is known as modulation . Popular analog modulation techniques include amplitude modulation and frequency modulation . The choice of modulation affects
4332-493: The viscosity of gases, and propose a system of defining physical quantities—now known as dimensional analysis . Maxwell would often attend lectures at the Royal Institution , where he came into regular contact with Michael Faraday . The relationship between the two men could not be described as being close, because Faraday was 40 years Maxwell's senior and showed signs of senility . They nevertheless maintained
4446-429: The 1850s had shown the relationship of different forms of electromagnetic radiation including the possibility of invisible airborne waves (later called "radio waves"). In his classic physics experiments of 1888, Heinrich Hertz proved Maxwell's theory by transmitting radio waves with a spark-gap transmitter , and detected them by using simple electrical devices. Other physicists experimented with these new waves and in
4560-452: The 19th-century scientist having the greatest influence on 20th-century physics. His contributions to the science are considered by many to be of the same magnitude as those of Isaac Newton and Albert Einstein . In the millennium poll—a survey of the 100 most prominent physicists—Maxwell was voted the third greatest physicist of all time, behind only Newton and Einstein, with another survey of rank-and-file physicists also voting him third. On
4674-637: The Academy in 1847 at age 16 and began attending classes at the University of Edinburgh . He had the opportunity to attend the University of Cambridge , but decided, after his first term, to complete the full course of his undergraduate studies at Edinburgh. The academic staff of the university included some highly regarded names; his first-year tutors included Sir William Hamilton , who lectured him on logic and metaphysics , Philip Kelland on mathematics, and James Forbes on natural philosophy . He did not find his classes demanding, and was, therefore, able to immerse himself in private study during free time at
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4788-817: The Clerk family of Penicuik , holders of the baronetcy of Clerk of Penicuik . His father's brother was the 6th baronet . He had been born "John Clerk", adding "Maxwell" to his own after he inherited (as an infant in 1793) the Middlebie estate, a Maxwell property in Dumfriesshire. James was a first cousin of both the artist Jemima Blackburn (the daughter of his father's sister) and the civil engineer William Dyce Cay (the son of his mother's brother). Cay and Maxwell were close friends and Cay acted as his best man when Maxwell married. Maxwell's parents met and married when they were well into their thirties; his mother
4902-661: The Moon with Apollo 11 in 1969 was enabled by NASA 's adoption of advances in semiconductor electronic technology , including MOSFETs in the Interplanetary Monitoring Platform (IMP) and silicon integrated circuit chips in the Apollo Guidance Computer (AGC). The development of MOS integrated circuit technology in the 1960s led to the invention of the microprocessor in the early 1970s. The first single-chip microprocessor
5016-580: The Royal Academy of Natural Sciences and Arts of Barcelona. Salva's electrolyte telegraph system was very innovative though it was greatly influenced by and based upon two discoveries made in Europe in 1800—Alessandro Volta's electric battery for generating an electric current and William Nicholson and Anthony Carlyle's electrolysis of water. Electrical telegraphy may be considered the first example of electrical engineering. Electrical engineering became
5130-709: The Transformation of Surfaces by Bending" to the Cambridge Philosophical Society . This is one of the few purely mathematical papers he had written, demonstrating his growing stature as a mathematician. Maxwell decided to remain at Trinity after graduating and applied for a fellowship, which was a process that he could expect to take a couple of years. Buoyed by his success as a research student, he would be free, apart from some tutoring and examining duties, to pursue scientific interests at his own leisure. The nature and perception of colour
5244-402: The air. Gin a body hit a body, Will it fly? And where? A collection of his poems was published by his friend Lewis Campbell in 1882. Descriptions of Maxwell remark upon his remarkable intellectual qualities being matched by social awkwardness. Maxwell wrote the following aphorism for his own conduct as a scientist: He that would enjoy life and act with freedom must have the work of
5358-558: The amplifier tube, called the triode . In 1920, Albert Hull developed the magnetron which would eventually lead to the development of the microwave oven in 1946 by Percy Spencer . In 1934, the British military began to make strides toward radar (which also uses the magnetron) under the direction of Dr Wimperis, culminating in the operation of the first radar station at Bawdsey in August 1936. In 1941, Konrad Zuse presented
5472-815: The applications of computer engineering. Photonics and optics deals with the generation, transmission, amplification, modulation, detection, and analysis of electromagnetic radiation . The application of optics deals with design of optical instruments such as lenses , microscopes , telescopes , and other equipment that uses the properties of electromagnetic radiation. Other prominent applications of optics include electro-optical sensors and measurement systems, lasers , fiber-optic communication systems, and optical disc systems (e.g. CD and DVD). Photonics builds heavily on optical technology, supplemented with modern developments such as optoelectronics (mostly involving semiconductors ), laser systems, optical amplifiers and novel materials (e.g. metamaterials ). Mechatronics
5586-499: The behaviour of governors —devices that control the speed of steam engines—thereby establishing the theoretical basis of control engineering. In his paper "On reciprocal figures, frames and diagrams of forces" (1870) he discussed the rigidity of various designs of lattice. He wrote the textbook Theory of Heat (1871) and the treatise Matter and Motion (1876). Maxwell was also the first to make explicit use of dimensional analysis , in 1871. In 1871 he returned to Cambridge to become
5700-478: The boy. Maxwell was sent to the prestigious Edinburgh Academy . He lodged during term times at the house of his aunt Isabella. During this time his passion for drawing was encouraged by his older cousin Jemima. The 10-year-old Maxwell, having been raised in isolation on his father's countryside estate, did not fit in well at school. The first year had been full, obliging him to join the second year with classmates
5814-487: The centenary of Maxwell's birthday, his work was described by Einstein as the "most profound and the most fruitful that physics has experienced since the time of Newton". When Einstein visited the University of Cambridge in 1922, he was told by his host that he had done great things because he stood on Newton's shoulders; Einstein replied: "No I don't. I stand on the shoulders of Maxwell." Tom Siegfried described Maxwell as "one of those once-in-a-century geniuses who perceived
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#17327732469605928-413: 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
6042-467: 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 2,100 miles (3,400 km). Millimetre wave communication was first investigated by Jagadish Chandra Bose during 1894–1896, when he reached an extremely high frequency of up to 60 GHz in his experiments. He also introduced
6156-485: The day continually before his eyes. Not yesterday's work, lest he fall into despair, not to-morrow's, lest he become a visionary not that which ends with the day, which is a worldly work, nor yet that only which remains to eternity, for by it he cannot shape his action. Happy is the man who can recognize in the work of to-day a connected portion of the work of life, and an embodiment of the work of eternity. The foundations of his confidence are unchangeable, for he has been made
6270-500: The design of devices to measure physical quantities such as pressure , flow , and temperature. The design of such instruments requires a good understanding of physics that often extends beyond electromagnetic theory . For example, flight instruments measure variables such as wind speed and altitude to enable pilots the control of aircraft analytically. Similarly, thermocouples use the Peltier-Seebeck effect to measure
6384-561: The design of new hardware . 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 embedded devices including video game consoles and DVD players . Computer engineers are involved in many hardware and software aspects of computing. Robots are one of
6498-577: The desired manner. To implement such controllers, electronics control engineers may use electronic circuits , digital signal processors , microcontrollers , and programmable logic controllers (PLCs). Control engineering has a wide range of applications from the flight and propulsion systems of commercial airliners to the cruise control present in many modern automobiles . It also plays an important role in industrial automation . Control engineers often use feedback when designing control systems . For example, in an automobile with cruise control
6612-420: 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 processing deals with the analysis and manipulation of signals . Signals can be either analog , in which case
6726-566: The end of his first term transferred to Trinity , where he believed it would be easier to obtain a fellowship . At Trinity he was elected to the elite secret society known as the Cambridge Apostles . Maxwell's intellectual understanding of his Christian faith and of science grew rapidly during his Cambridge years. He joined the "Apostles", an exclusive debating society of the intellectual elite, where through his essays he sought to work out this understanding. Now my great plan, which
6840-537: The existence of radio waves . As a result of his equations, and other important contributions such as introducing an effective method to deal with network problems and linear conductors, Maxwell is regarded as a founder of the modern field of electrical engineering . Maxwell was the first to derive the Maxwell–Boltzmann distribution , a statistical means of describing aspects of the kinetic theory of gases , which he worked on sporadically throughout his career. He
6954-526: The first Cavendish Professor of Physics . Maxwell was put in charge of the development of the Cavendish Laboratory , supervising every step in the progress of the building and of the purchase of the collection of apparatus. One of Maxwell's last great contributions to science was the editing (with copious original notes) of the research of Henry Cavendish , from which it appeared that Cavendish researched, amongst other things, such questions as
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#17327732469607068-570: The first Department of Electrical Engineering in the United States. In the same year, University College London founded the first chair of electrical engineering in Great Britain. Professor Mendell P. Weinbach at University of Missouri established the electrical engineering department in 1886. Afterwards, universities and institutes of technology gradually started to offer electrical engineering programs to their students all over
7182-535: The first additional part, he discussed the nature of electrostatics and displacement current . In the second additional part, he dealt with the rotation of the plane of the polarisation of light in a magnetic field, a phenomenon that had been discovered by Faraday and is now known as the Faraday effect . In 1865 Maxwell resigned the chair at King's College, London, and returned to Glenlair with Katherine. In his paper "On governors" (1868) he mathematically described
7296-583: The future it is hoped the devices will help build tiny implantable medical devices and improve optical communication . In aerospace engineering and robotics , an example is the most recent electric propulsion and ion propulsion. Electrical engineers typically possess an academic degree with a major in electrical engineering, electronics engineering , electrical engineering technology , or electrical and electronic engineering. The same fundamental principles are taught in all programs, though emphasis may vary according to title. The length of study for such
7410-533: 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. Telecommunications engineering focuses on
7524-460: The guidance of a 16-year-old hired tutor. Little is known about the young man hired to instruct Maxwell, except that he treated the younger boy harshly, chiding him for being slow and wayward. The tutor was dismissed in November 1841. James' father took him to Robert Davidson 's demonstration of electric propulsion and magnetic force on 12 February 1842, an experience with profound implications for
7638-481: The hidden course of streams and bell-wires, the way the water gets from the pond through the wall.... Recognising the boy's potential, Maxwell's mother Frances took responsibility for his early education, which in the Victorian era was largely the job of the woman of the house. At eight he could recite long passages of John Milton and the whole of the 119th psalm (176 verses). Indeed, his knowledge of scripture
7752-458: The international standardization of the units volt , ampere , coulomb , ohm , farad , and henry . This was achieved at an international conference in Chicago in 1893. The publication of these standards formed the basis of future advances in standardization in various industries, and in many countries, the definitions were immediately recognized in relevant legislation. During these years,
7866-666: The jelly. Through this practice he discovered photoelasticity , which is a means of determining the stress distribution within physical structures. At age 18, Maxwell contributed two papers for the Transactions of the Royal Society of Edinburgh . One of these, "On the Equilibrium of Elastic Solids", laid the foundation for an important discovery later in his life, which was the temporary double refraction produced in viscous liquids by shear stress . His other paper
7980-556: The latter half of the 19th century after the commercialization of the electric telegraph , the telephone, and electrical power generation, distribution, and use. Electrical engineering is divided into a wide range of different fields, including computer engineering , systems engineering , power engineering , telecommunications , radio-frequency engineering , signal processing , instrumentation , photovoltaic cells , electronics , and optics and photonics . Many of these disciplines overlap with other engineering branches, spanning
8094-446: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=JCM&oldid=1201944371 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages James Clerk Maxwell James Clerk Maxwell FRS FRSE (13 June 1831 – 5 November 1879)
8208-399: The management skills of a project manager . The tools and equipment that an individual engineer may need are similarly variable, ranging from a simple voltmeter to sophisticated design and manufacturing software. Electricity has been a subject of scientific interest since at least the early 17th century. William Gilbert was a prominent early electrical scientist, and was the first to draw
8322-574: The marriage record, Maxwell is listed as Professor of Natural Philosophy in Marischal College, Aberdeen. Katherine was seven years Maxwell's senior. Comparatively little is known of her, although it is known that she helped in his lab and worked on experiments in viscosity . Maxwell's biographer and friend, Lewis Campbell, adopted an uncharacteristic reticence on the subject of Katherine, though describing their married life as "one of unexampled devotion". In 1860 Marischal College merged with
8436-446: The mid-to-late 1950s, the term radio engineering gradually gave way to the name electronic engineering . Before the invention of the integrated circuit in 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
8550-557: The minister and his wife. On his return to Cambridge, Maxwell writes to his recent host a chatty and affectionate letter including the following testimony, ... I have the capacity of being more wicked than any example that man could set me, and ... if I escape, it is only by God's grace helping me to get rid of myself, partially in science, more completely in society, —but not perfectly except by committing myself to God ... In November 1851, Maxwell studied under William Hopkins , whose success in nurturing mathematical genius had earned him
8664-511: The multi-disciplinary design issues of complex electrical and mechanical systems. The term mechatronics is typically used to refer to macroscopic systems but futurists have predicted the emergence of very small electromechanical devices. Already, such small devices, known as microelectromechanical 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
8778-449: The necessary references, but died on 2 April at Glenlair before either knew the result of Maxwell's candidacy. He accepted the professorship at Aberdeen, leaving Cambridge in November 1856. The 25-year-old Maxwell was a good 15 years younger than any other professor at Marischal. He engaged himself with his new responsibilities as head of a department, devising the syllabus and preparing lectures. He committed himself to lecturing 15 hours
8892-483: The neighbouring King's College to form the University of Aberdeen . There was no room for two professors of Natural Philosophy, so Maxwell, despite his scientific reputation, found himself laid off. He was unsuccessful in applying for Forbes's recently vacated chair at Edinburgh, the post instead going to Tait . Maxwell was granted the Chair of Natural Philosophy at King's College, London , instead. After recovering from
9006-519: The new Society of Telegraph Engineers (soon to be renamed the Institution of Electrical Engineers ) where he was regarded by other members as the first of their cohort. By the end of the 19th century, the world had been forever changed by the rapid communication made possible by the engineering development of land-lines, submarine cables , and, from about 1890, wireless telegraphy . Practical applications and advances in such fields created an increasing need for standardized units of measure . They led to
9120-465: The nickname of " senior wrangler -maker". In 1854, Maxwell graduated from Trinity with a degree in mathematics. He scored second highest in the final examination, coming behind Edward Routh and earning himself the title of Second Wrangler. He was later declared equal with Routh in the more exacting ordeal of the Smith's Prize examination. Immediately after earning his degree, Maxwell read his paper "On
9234-515: The orthodox unread admit, and shut up the subject as haunted. But a Candle is coming to drive out all Ghosts and Bugbears. Let us follow the light. In the summer of his third year, Maxwell spent some time at the Suffolk home of the Rev. C. B. Tayler , the uncle of a classmate, G. W. H. Tayler. The love of God shown by the family impressed Maxwell, particularly after he was nursed back from ill health by
9348-525: The passage of information with uncertainty ( electrical noise ). The first working transistor was a point-contact transistor invented by John Bardeen and Walter Houser Brattain while working under William Shockley at the Bell Telephone Laboratories (BTL) in 1947. They then invented the bipolar junction transistor in 1948. While early junction transistors were relatively bulky devices that were difficult to manufacture on
9462-490: The physical world with sharper senses than those around him". James Clerk Maxwell was born on 13 June 1831 at 14 India Street, Edinburgh , to John Clerk Maxwell of Middlebie , an advocate, and Frances Cay, daughter of Robert Hodshon Cay and sister of John Cay . (His birthplace now houses a museum operated by the James Clerk Maxwell Foundation .) His father was a man of comfortable means of
9576-422: The problem, proving that a regular solid ring could not be stable, while a fluid ring would be forced by wave action to break up into blobs. Since neither was observed, he concluded that the rings must be composed of numerous small particles he called "brick-bats", each independently orbiting Saturn. Maxwell was awarded the £130 Adams Prize in 1859 for his essay "On the stability of the motion of Saturn's rings"; he
9690-401: The process developed devices for transmitting and detecting them. In 1895, Guglielmo Marconi began work on a way to adapt the known methods of transmitting and detecting these "Hertzian waves" into a purpose-built commercial wireless telegraphic system. 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
9804-731: The religion of the Bible—is the only scheme or form of belief which disavows any possessions on such a tenure. Here alone all is free. You may fly to the ends of the world and find no God but the Author of Salvation. You may search the Scriptures and not find a text to stop you in your explorations. ... The Old Testament and the Mosaic Law and Judaism are commonly supposed to be "Tabooed" by the orthodox. Sceptics pretend to have read them and have found certain witty objections ... which too many of
9918-662: The rings were composed of particles. It is now understood, however, that the rings' particles are not totally stable, being pulled by gravity onto Saturn. The rings are expected to vanish entirely over the next 300 million years. In 1857 Maxwell befriended the Reverend Daniel Dewar, who was then the Principal of Marischal. Through him Maxwell met Dewar's daughter, Katherine Mary Dewar . They were engaged in February 1858 and married in Aberdeen on 2 June 1858. On
10032-411: The school syllabus and he did not pay particular attention to examination performance. He wrote his first scientific paper at the age of 14. In it, he described a mechanical means of drawing mathematical curves with a piece of twine, and the properties of ellipses , Cartesian ovals , and related curves with more than two foci . The work, of 1846, "On the description of oval curves and those having
10146-425: 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 modulation and demodulation of signals for telecommunications. For digital signals, signal processing may involve
10260-411: The study of electricity was largely considered to be a subfield of physics since early electrical technology was considered electromechanical in nature. The Technische Universität Darmstadt founded the world's first department of electrical engineering in 1882 and introduced the first-degree course in electrical engineering in 1883. The first electrical engineering degree program in the United States
10374-444: 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. Computer engineering deals with the design of computers and computer systems . This may involve
10488-478: The theoretical basis of alternating current engineering. The spread in the use of AC set off in the United States what has been called the war of the currents between a George Westinghouse backed AC system and a Thomas Edison backed DC power system, with AC being adopted as the overall standard. During the development of radio , many scientists and inventors contributed to radio technology and electronics. The mathematical work of James Clerk Maxwell during
10602-429: The university and particularly when back home at Glenlair. There he would experiment with improvised chemical, electric, and magnetic apparatus; however, his chief concerns regarded the properties of polarised light . He constructed shaped blocks of gelatine , subjected them to various stresses , and with a pair of polarising prisms given to him by William Nicol , viewed the coloured fringes that had developed within
10716-424: The use of semiconductor junctions to detect radio waves, when he patented the radio crystal detector in 1901. In 1897, Karl Ferdinand Braun introduced the cathode-ray tube as part of an oscilloscope , a crucial enabling technology for electronic television . John Fleming invented the first radio tube, the diode , in 1904. Two years later, Robert von Lieben and Lee De Forest independently developed
10830-557: The use of transformers , developed rapidly in the 1880s and 1890s with transformer designs by Károly Zipernowsky , Ottó Bláthy and Miksa Déri (later called ZBD transformers), Lucien Gaulard , John Dixon Gibbs and William Stanley Jr. Practical AC motor designs including induction motors were independently invented by Galileo Ferraris and Nikola Tesla and further developed into a practical three-phase form by Mikhail Dolivo-Dobrovolsky and Charles Eugene Lancelot Brown . Charles Steinmetz and Oliver Heaviside contributed to
10944-485: The vehicle's speed is continuously monitored and fed back to the system which adjusts the motor's power output accordingly. Where there is regular feedback, control theory can be used to determine how the system responds to such feedback. Control engineers also work in robotics to design autonomous systems using control algorithms which interpret sensory feedback to control actuators that move robots such as autonomous vehicles , autonomous drones and others used in
11058-414: The world's first form of electric telegraphy , using 24 different wires, one for each letter of the alphabet. This telegraph connected two rooms. It was an electrostatic telegraph that moved gold leaf through electrical conduction. In 1795, Francisco Salva Campillo proposed an electrostatic telegraph system. Between 1803 and 1804, he worked on electrical telegraphy, and in 1804, he presented his report at
11172-560: The world. During these decades the use of electrical engineering increased dramatically. In 1882, Thomas Edison switched on the world's first large-scale electric power network that provided 110 volts— direct current (DC)—to 59 customers on Manhattan Island in New York City. In 1884, Sir Charles Parsons invented the steam turbine allowing for more efficient electric power generation. Alternating current , with its ability to transmit power more efficiently over long distances via
11286-417: The young James Clerk Maxwell, in his mid to late 20s, a man of middling height, with frame strongly knit, and a certain spring and elasticity in his gait; dressed for comfortable ease rather than elegance; a face expressive at once of sagacity and good humour, but overlaid with a deep shade of thoughtfulness; features boldly put pleasingly marked; eyes dark and glowing; hair and beard perfectly black, and forming
11400-495: Was "Rolling Curves" and, just as with the paper "Oval Curves" that he had written at the Edinburgh Academy, he was again considered too young to stand at the rostrum to present it himself. The paper was delivered to the Royal Society by his tutor Kelland instead. In October 1850, already an accomplished mathematician, Maxwell left Scotland for the University of Cambridge . He initially attended Peterhouse , but before
11514-415: Was a Scottish physicist and mathematician who was responsible for the classical theory of electromagnetic radiation , which was the first theory to describe electricity, magnetism and light as different manifestations of the same phenomenon. Maxwell's equations for electromagnetism achieved the second great unification in physics , where the first one had been realised by Isaac Newton . Maxwell
11628-521: Was already detailed; he could give chapter and verse for almost any quotation from the Psalms. His mother was taken ill with abdominal cancer and, after an unsuccessful operation, died in December 1839 when he was eight years old. His education was then overseen by his father and his father's sister-in-law Jane, both of whom played pivotal roles in his life. His formal schooling began unsuccessfully under
11742-530: Was also key in the creation of statistical mechanics . With the publication of " A Dynamical Theory of the Electromagnetic Field " in 1865, Maxwell demonstrated that electric and magnetic fields travel through space as waves moving at the speed of light . He proposed that light is an undulation in the same medium that is the cause of electric and magnetic phenomena. The unification of light and electrical phenomena led to his prediction of
11856-638: Was astonished at his lucidity and the immense power and scope of his memory, but comments more particularly, ... his illness drew out the whole heart and soul and spirit of the man: his firm and undoubting faith in the Incarnation and all its results; in the full sufficiency of the Atonement; in the work of the Holy Spirit. He had gauged and fathomed all the schemes and systems of philosophy, and had found them utterly empty and unsatisfying—"unworkable"
11970-503: Was conceived of old, ... is to let nothing be wilfully left unexamined. Nothing is to be holy ground consecrated to Stationary Faith, whether positive or negative. All fallow land is to be ploughed up and a regular system of rotation followed. ... Never hide anything, be it weed or no, nor seem to wish it hidden. ... Again I assert the Right of Trespass on any plot of Holy Ground which any man has set apart. ... Now I am convinced that no one but
12084-775: Was his own word about them—and he turned with simple faith to the Gospel of the Saviour. As death approached Maxwell told a Cambridge colleague, I have been thinking how very gently I have always been dealt with. I have never had a violent shove all my life. The only desire which I can have is like David to serve my own generation by the will of God, and then fall asleep. Maxwell is buried at Parton Kirk, near Castle Douglas in Galloway close to where he grew up. The extended biography The Life of James Clerk Maxwell , by his former schoolfellow and lifelong friend Professor Lewis Campbell ,
12198-505: Was nearly 40 when he was born. They had had one earlier child, a daughter named Elizabeth, who died in infancy. When Maxwell was young his family moved to Glenlair , in Kirkcudbrightshire, which his parents had built on the estate which comprised 1,500 acres (610 ha). All indications suggest that Maxwell had maintained an unquenchable curiosity from an early age. By the age of three, everything that moved, shone, or made
12312-536: Was one such interest which he had begun at the University of Edinburgh while he was a student of Forbes. With the coloured spinning tops invented by Forbes, Maxwell was able to demonstrate that white light would result from a mixture of red, green, and blue light. His paper "Experiments on Colour" laid out the principles of colour combination and was presented to the Royal Society of Edinburgh in March 1855. Maxwell
12426-538: Was published in 1882. His collected works were issued in two volumes by the Cambridge University Press in 1890. The executors of Maxwell's estate were his physician George Edward Paget , G. G. Stokes , and Colin Mackenzie, who was Maxwell's cousin. Overburdened with work, Stokes passed Maxwell's papers to William Garnett , who had effective custody of the papers until about 1884. There
12540-489: Was started at Massachusetts Institute of Technology (MIT) in the physics department under Professor Charles Cross, though it was Cornell University to produce the world's first electrical engineering graduates in 1885. The first course in electrical engineering was taught in 1883 in Cornell's Sibley College of Mechanical Engineering and Mechanic Arts . In about 1885, Cornell President Andrew Dickson White established
12654-458: Was the Intel 4004 , released in 1971. The Intel 4004 was designed and realized by Federico Faggin at Intel with his silicon-gate MOS technology, along with Intel's Marcian Hoff and Stanley Mazor and Busicom's Masatoshi Shima. The microprocessor led to the development of microcomputers and personal computers, and the microcomputer revolution . One of the properties of electricity is that it
12768-474: Was the first truly compact transistor that could be miniaturised and mass-produced for a wide range of uses. It revolutionized the electronics industry , becoming the most widely used electronic device in the world. The MOSFET made it possible to build high-density integrated circuit chips. The earliest experimental MOS IC chip to be fabricated was built by Fred Heiman and Steven Hofstein at RCA Laboratories in 1962. MOS technology enabled Moore's law ,
12882-461: Was the only entrant to have made enough headway to submit an entry. His work was so detailed and convincing that when George Biddell Airy read it he commented, "It is one of the most remarkable applications of mathematics to physics that I have ever seen." It was considered the final word on the issue until direct observations by the Voyager flybys of the 1980s confirmed Maxwell's prediction that
12996-418: Was this time able to deliver it himself. Maxwell was made a fellow of Trinity on 10 October 1855, sooner than was the norm, and was asked to prepare lectures on hydrostatics and optics and to set examination papers. The following February he was urged by Forbes to apply for the newly vacant Chair of Natural Philosophy at Marischal College , Aberdeen . His father assisted him in the task of preparing
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