Broadband Global Area Network

The Broadband Global Area Network or BGAN for short, is a global Satellite Internet Network with telephony using portable terminals. The terminals are normally used to connect a laptop computer to broadband Internet in remote locations, although as long as line-of-sight to the satellite exists, the terminal can be used anywhere. The value of BGAN terminals is that unlike other satellite Internet services which require bulky & heavy satellite dishes to connect, a BGAN terminal is smaller than a laptop and thus can be carried anywhere, and used globally. The network is provided by INMARSAT and uses three geostationary satellites with global service (except for the polar regions) ^[1].Downlink speeds of high-end BGAN terminals are up to 492kb/s and upload speeds slightly lower at 300-400kb/s. As with all satellite connections, latency is an issue. BGAN uses improved PEP software or other TCP packet accelerators or third party VPN's such as Skypipe to improve performance.

Dell Dimension 8200 (2.8GHz Pentium 4)

As befits a performance-orientated PC, the 2.8GHz Dimension 8200 uses Rambus memory – two of the motherboard’s four RIMM slots are filled with 256MB PC800 modules, giving a total of 512MB and a theoretical RAM capacity of 2GB. Co-ordinating the CPU, memory and peripheral subsystems is Intel’s 850E chipset, which supports the 533MHz frontside bus but cannot handle the latest Ultra-ATA/133 hard disks or USB 2.0 peripherals. Dell has got around the USB 2.0 problem in previous review systems by fitting a PCI card, but did not do so with our 2.8GHz machine. Digital video enthusiasts should note that FireWire is not available as standard on this PC, although there are two free PCI slots available for adding any missing functionality. Hard disk storage is provided by a fast 7,200rpm 120GB Western Digital drive, while optical media are taken care of by a Philips DVD+RW drive and a fast 48-speed CD-ROM drive. There are no spare external 5.25in.

iPod

iPod is a brand of portable media players designed and marketed by Apple Inc. and launched on October 23, 2001 (2001-10-23). The product line-up includes the hard drive-based iPod Classic, the touchscreen iPod Touch, the video-capable iPod Nano, and the compact iPod Shuffle. The iPhone can function as an iPod but is generally treated as a separate product. Former iPod models include the iPod Mini and the spin-off iPod Photo (since reintegrated into the main iPod Classic line). iPod Classic models store media on an internal hard drive, while all other models use flash memory to enable their smaller size (the discontinued Mini used a Microdrive miniature hard drive). As with many other digital music players, iPods, excluding the iPod Touch, can also serve as external data storage devices. Storage capacity varies by model.Apple's iTunes software can be used to transfer music to the devices from computers using certain versions of Apple Macintosh and Microsoft Windows operating systems.[2] For users who choose not to use Apple's software or whose computers cannot run iTunes software, several open source alternatives to iTunes are also available.[3] iTunes and its alternatives may also transfer photos, videos, games, contact information, e-mail settings, Web bookmarks, and calendars to iPod models supporting those features. As of September 2008[update], more than 173 million iPods had been sold worldwide, making it the best-selling digital audio player series in history

A Laptop

A laptop (also known as a notebook) is a personal computer designed for mobile use small enough to sit on one's lap.[1] A laptop includes most of the typical components of a typical desktop computer, including a display, a keyboard, a pointing device (a touchpad, also known as a trackpad, or a pointing stick) as well as a battery, into a single small and light unit. The rechargeable battery required is charged from an AC/DC adapter (ie, a wall wart) and typically stores enough energy to run the laptop for several hours.Laptops are usually shaped like a large notebook with thicknesses between 0.7–1.5 inches (18–38 mm) and dimensions ranging from 10x8 inches (27x22cm, 13" display) to 15x11 inches (39x28cm, 17" display) and up. Modern laptops weigh 3 to 12 pounds (1.4 to 5.4 kg); older laptops were usually heavier. Most laptops are designed in the flip form factor to protect the screen and the keyboard when closed. Modern 'tablet' laptops have a complex joint between the keyboard housing and the display, permitting the display panel to twist and then lay flat on the keyboard housing. They usually have a touchscreen display and some include handwriting recognition or graphics drawing capability.

Epson PowerLite 83+ Multimedia Projector

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Parallel plate model

Dielectric is placed between two conducting plates, each of area A and with a separation of d

The simplest capacitor consists of two parallel conductive plates separated by a dielectric with permittivity ε. The model may also be used to make qualitative predictions for other device geometries. The plates are considered to extend uniformly over an area A and a charge density ±ρ = ±Q/A exists on their surface. Assuming that the width of the plates is much greater than their separation d, the electric field near the centre of the device will be uniform with the magnitude E = ρ/ε. The voltage is defined as the line integral of the electric field between the plates

Solving this for C = Q/V reveals that capacitance increases with area and decreases with separation

.

The capacitance is therefore greatest in devices made from materials with a high permittivity.

capacitor

A capacitor or condenser is a passive electronic component consisting of a pair of conductors separated by a dielectric. When a voltage potential difference exists between the conductors, an electric field is present in the dielectric. This field stores energy and produces a mechanical force between the plates. The effect is greatest between wide, flat, parallel, narrowly separated conductors.An ideal capacitor is characterized by a single constant value, capacitance, which is measured in farads. This is the ratio of the electric charge on each conductor to the potential difference between them. In practice, the dielectric between the plates passes a small amount of leakage current. The conductors and leads introduce an equivalent series resistance and the dielectric has an electric field strength limit resulting in a breakdown voltage.The properties of capacitors in a circuit may determine the resonant frequency and quality factor of a resonant circuit, power dissipation and operating frequency in a digital logic circuit, energy capacity in a high-power system, and many other important aspects.

Rectifier output smoothing

While half-wave and full-wave rectification suffice to deliver a form of DC output, neither produces constant-voltage DC. In order to produce steady DC from a rectified AC supply, a smoothing circuit, sometimes called a filter^[1], is required. In its simplest form this can be what is known as a reservoir capacitor, filter capacitor or smoothing capacitor, placed at the DC output of the rectifier. There will still remain an amount of AC ripple voltage where the voltage is not completely smoothed. RC-Filter Rectifier: This circuit was designed and simulated using Multisim 8 software.Sizing of the capacitor represents a tradeoff. For a given load, a larger capacitor will reduce ripple but will cost more and will create higher peak currents in the transformer secondary and in the supply feeding it. In extreme cases where many rectifiers are loaded onto a power distribution circuit, it may prove difficult for the power distribution authority to maintain a correctly shaped sinusoidal voltage curve.

Full-wave rectification

A full-wave rectifier converts the whole of the input waveform to one of constant polarity (positive or negative) at its output. Full-wave rectification converts both polarities of the input waveform to DC (direct current), and is more efficient. However, in a circuit with a non-center tapped transformer, four diodes are required instead of the one needed for half-wave rectification. (See semiconductors, diode). Four rectifiers arranged this way are called a diode bridge or bridge rectifier:

Gratz bridge rectifier: a full-wave rectifier using 4 diodes.For single-phase AC, if the transformer is center-tapped, then two diodes back-to-back (i.e. anodes-to-anode or cathode-to-cathode) can form a full-wave rectifier. Twice as many windings are required on the transformer secondary to obtain the same output voltage compared to the bridge rectifier above.

Selenium and copper oxide rectifiers

Once common until replaced by more compact and less costly silicon solid-state rectifiers, these units used stacks of metal plates and took advantage of the semiconductor properties of selenium or copper oxide. ^[6] While selenium rectifiers were lighter in weight and used less power than comparable vacuum tube rectifiers, they had the disadvantage of finite life expectancy, increasing resistance with age, and were only suitable to use at low frequencies. Both selenium and copper oxide rectifiers have somewhat better tolerance of momentary voltage transients than silicon rectifiers.

Typically these rectifiers were made up of stacks of metal plates or washers, held together by a central bolt, with the number of stacks determined by voltage; each cell was rated for about 20 volts. An automotive battery charger rectifier might have only one cell: the high-voltage power supply for a vacuum tube might have dozens of stacked plates. Current density in an air-cooled selenium stack was about 600 mA per square inch of active area (about 90 mA per square centimeter).

Vacuum tube (valve)

Since the discovery of the Edison effect or thermionic emission, various vacuum tube devices have been developed to rectify alternating currents. Low-power devices are used as signal detectors, first used in radio by Fleming in 1904. Many vacuum-tube devices also used vacuum rectifiers in their power supplies, for example the All American Five radio receiver. Vacuum rectifiers were made for very high voltages, such as the high voltage power supply for the cathode ray tube of television receivers, and the kenotron used for power supply in X-ray equipment. However, vacuum rectifiers generally had low current capacity owing to the maximum current density that could be obtained by electrodes heated to temperatures compatible with long life. Another limitation of the vacuum tube rectifier was that the heater power supply often required special arrangements to insulate it from the high voltages of the rectifier circuit.

A rectifier

A rectifier is an electrical device that converts alternating current (AC) to direct current (DC), a process known as rectification. Rectifiers have many uses including as components of power supplies and as detectors of radio signals. Rectifiers may be made of solid state diodes, vacuum tube diodes, mercury arc valves, and other components.

A device which performs the opposite function (converting DC to AC) is known as an inverter.

When only one diode is used to rectify AC (by blocking the negative or positive portion of the waveform), the difference between the term diode and the term rectifier is merely one of usage, i.e., the term rectifier describes a diode that is being used to convert AC to DC. Almost all rectifiers comprise a number of diodes in a specific arrangement for more efficiently converting AC to DC than is possible with only one diode. Before the development of silicon semiconductor rectifiers, vacuum tube diodes and copper(I) oxide or selenium rectifier stacks were used.

Early radio receivers, called crystal radios, used a "cat's whisker" of fine wire pressing on a crystal of galena (lead sulfide) to serve as a point-contact rectifier or "crystal detector". In gas heating systems flame rectification can be used to detect a flame. Two metal electrodes in the outer layer of the flame provide a current path and rectification of an applied alternating voltage, but only while the flame is present.

The Diodes

The Diodes were a Canadian punk/new wave band formed in 1976. They released four albums: Diodes (1977), Released (1979), Action-Reaction (1980), and Survivors (1982). One of the first Toronto bands playing that style of music, The Diodes helped foster the scene in the city. Along with manager Ralph Alfonso, they opened the first Canadian punk nightclub in 1977, called Crash 'n' Burn, where many of the city's punk bands at that time played. The first band to play the club was The Nerves (Peter Case, Jack Lee, Paul Collins), on a double bill with The Diodes. The club was closed at the end of the summer of 1977 due to complaints by the Liberal Party of Ontario (the principal tenants of the building).The club was the subject of a movie by experimental filmmaker Ross McLaren Dialed Crash 'n' Burn, one of the few documents on film of this period. Footage of the club in its heyday also exists in the CBC Television archives because it was the subject of a TV special in 1977. The band put out their first record at this time, a vinyl single featuring Bruce Eves and Amerigo Maras of CEAC. Mickey Skin of all-girl punk band The Curse spews profanity on one side; the Diodes provide musical backing on the other - released on the Crash and Burn label. One side was called "War," the other "Raw," and was one of the first punk records to come out of Toronto. This single was actually an issue of the CEAC Newsletter (published by the Centre For Experimental Art and Communication, the owners of the building that housed the Crash 'n' Burn club).

Resistor

A resistor is a two-terminal electronic component designed to oppose an electric current by producing a voltage drop between its terminals in proportion to the current, that is, in accordance with Ohm's law:

V = IR

Resistors are used as part of electrical networks and electronic circuits. They are extremely commonplace in most electronic equipment. Practical resistors can be made of various compounds and films, as well as resistance wire (wire made of a high-resistivity alloy, such as nickel/chrome).

The primary characteristics of resistors are their resistance and the power they can dissipate. Other characteristics include temperature coefficient, noise, and inductance. Less well-known is critical resistance, the value below which power dissipation limits the maximum permitted current flow, and above which the limit is applied voltage. Critical resistance depends upon the materials constituting the resistor as well as its physical dimensions; it's determined by design.

Resistors can be integrated into hybrid and printed circuits, as well as integrated circuits. Size, and position of leads (or terminals) are relevant to equipment designers; resistors must be physically large enough not to overheat when dissipating their power.

Transistors

The first patent^[1] for the field-effect transistor principle was filed in Canada by Austrian-Hungarian physicist Julius Edgar Lilienfeld on October 22, 1925, but Lilienfeld did not publish any research articles about his devices. In 1934 German physicist Dr. Oskar Heil patented another field-effect transistor.

On 17 November 1947 John Bardeen and Walter Brattain, at AT&T Bell Labs, observed that when electrical contacts were applied to a crystal of germanium, the output power was larger than the input. William Shockley saw the potential in this and worked over the next few months greatly expanding the knowledge of semiconductors and is considered by many to be the "father" of the transistor. The term was coined by John R. Pierce.The transistor is considered by many to be the greatest invention of the twentieth-century,^[2] or as one of the greatest.^[3] It is the key active component in practically all modern electronics. Its importance in today's society rests on its ability to be mass produced using a highly automated process (fabrication) that achieves astonishingly low per-transistor costs.

Although several companies each produce over a billion individually-packaged (known as discrete) transistors every year,^[4] the vast majority of transistors produced are in integrated circuits (often shortened to IC, microchips or simply chips) along with diodes, resistors, capacitors and other electronic components to produce complete electronic circuits. A logic gate consists of about twenty transistors whereas an advanced microprocessor, as of 2006, can use as many as 1.7 billion transistors (MOSFETs).^[5] "About 60 million transistors were built this year [2002] ... for [each] man, woman, and child on Earth."^[6]

Hard disk drive

HDDs record data by magnetizing ferromagnetic material directionally, to represent either a 0 or a 1 binary digit. They read the data back by detecting the magnetization of the material. A typical HDD design consists of a spindle which holds one or more flat circular disks called platters, onto which the data are recorded. The platters are made from a non-magnetic material, usually aluminum alloy or glass, and are coated with a thin layer of magnetic material. Older disks used iron(III) oxide as the magnetic material, but current disks use a cobalt-based alloy.^{[citation needed]}A cross section of the magnetic surface in action. In this case the binary data is encoded using frequency modulation.

The platters are spun at very high speeds. Information is written to a platter as it rotates past devices called read-and-write heads that operate very close (tens of nanometers in new drives) over the magnetic surface. The read-and-write head is used to detect and modify the magnetization of the material immediately under it. There is one head for each magnetic platter surface on the spindle, mounted on a common arm. An actuator arm (or access arm) moves the heads on an arc (roughly radially) across the platters as they spin, allowing each head to access almost the entire surface of the platter as it spins. The arm is moved using a voice coil actuator or in some older designs a stepper motor.

CPU power dissipation

CPU power dissipation or Central processing unit power dissipation is the process in which Central processing units (or CPUs) consume electrical energy, and dissipate this energy by both the action of the switching devices contained in the CPU (such as transistors or vacuum tubes) and via the energy lost in the form of heat due to the resistivity of the electrical circuits. Designing CPUs that perform these tasks efficiently without overheating is a major consideration in nearly all CPU manufacturers to date.

Some implementations of CPUs use very little power, for example, the CPUs in mobile phones often use just a few hundred milliwatts of electricity. In comparison, CPUs in general purpose microcomputers dissipate significantly more power because of their higher complexity and speed. These microelectronic CPUs may consume power in the order of tens of watts. Historically, early CPUs implemented with vacuum tubes consumed power in the order of many kilowatts.

.

Bus (computing)

In computer architecture, a bus is a subsystem that transfers data between computer components inside a computer or between computers. Each bus defines its set of connectors to physically plug devices, cards or cables together.

Early computer buses were literally parallel electrical buses with multiple connections, but the term is now used for any physical arrangement that provides the same logical functionality as a parallel electrical bus. Modern computer buses can use both parallel and bit-serial connections, and can be wired in either a multidrop (electrical parallel) or daisy chain topology, or connected by switched hubs, as in the case of USB.

Early computer buses were bundles of wire that attached memory and peripherals. They were named after electrical buses, or busbars. Almost always, there was one bus for memory, and another for peripherals,^{[citation needed]} and these were accessed by separate instructions, with completely different timings and protocols.

One of the first complications was the use of interrupts. Early computers performed I/O by waiting in a loop for the peripheral to become ready. This was a waste of time for programs that had other tasks to do. Also, if the program attempted to perform those other tasks, it might take too long for the program to check again, resulting in loss of data. Engineers thus arranged for the peripherals to interrupt the CPU. The interrupts had to be prioritized, because the CPU can only execute code for one peripheral at a time, and some devices are more time-critical than others.

central processing unit (CPU)

A central processing unit (CPU) or processor is an electronic circuit that can execute computer programs. This broad definition can easily be applied to many early computers that existed long before the term "CPU" ever came into widespread usage. The term itself and its initialism have been in use in the computer industry at least since the early 1960s (Weik 1961). The form, design and implementation of CPUs have changed dramatically since the earliest examples, but their fundamental operation has remained much the same.

Early CPUs were custom-designed as a part of a larger, sometimes one-of-a-kind, computer. However, this costly method of designing custom CPUs for a particular application has largely given way to the development of mass-produced processors that are mkih for one or many purposes. This standardization trend generally began in the era of discrete transistor mainframes and minicomputers and has rapidly accelerated with the popularization of the integrated circuit (IC). The IC has allowed increasingly complex CPUs to be designed and manufactured to tolerances on the order of nanometers. Both the miniaturization and standardization of CPUs have increased the presence of these digital devices in modern life far beyond the limited application of dedicated computing machines. Modern microprocessors appear in everything from automobiles to cell phones to children's toys.

Electronic circuit

An Electronic circuit is a closed path formed by the interconnection of electronic components through which an electric current can flow. The electronic circuits may be physically constructed using any number of methods. Breadboards, perfboards or stripboards are common for testing new designs. Mass-produced circuits are typically built using a printed circuit board (PCB) that is used to mechanically support and electrically connect electronic components.

Electronic circuits can display highly complex behaviors, even though they are governed by the same laws of physics as simpler circuits.

Electronic circuits can usually be categorized as analog, discrete, or mixed-signal (a combination of analog and discrete) electronic circuits.those in which signals may vary continuously with time to correspond to the information being represented. Electronic equipment like voltage amplifiers, power amplifiers, tuning circuits, radios, and televisions are largely analog (with the exception of their control sections, which may be digital, especially in modern units).

motherboards

Most computer motherboards produced today are designed for IBM-compatible computers, which currently account for around 90% of global PC sales^{[citation needed]}. A motherboard, like a backplane, provides the electrical connections by which the other components of the system communicate, but unlike a backplane, it also hosts the central processing unit, and other subsystems and devices.

Motherboards are also used in many other electronics devices such as mobile phones,stop-watches,clocks,and other small electronc devices.

A typical desktop computer has its microprocessor, main memory, and other essential components on the motherboard. Other components such as external storage, controllers for video display and sound, and peripheral devices may be attached to the motherboard as plug-in cards or via cables, although in modern computers it is increasingly common to integrate some of these peripherals into the motherboard itself.

An important component of a motherboard is the microprocessor's supporting chipset, which provides the supporting interfaces between the CPU and the various buses and external components. This chipset determines, to an extent, the features and capabilities of the motherboard.

data compression

In computer science and information theory, data compression or source coding is the process of encoding information using fewer bits (or other information-bearing units) than an unencoded representation would use through use of specific encoding schemes.

As with any communication, compressed data communication only works when both the sender and receiver of the information understand the encoding scheme. For example, this text makes sense only if the receiver understands that it is intended to be interpreted as characters representing the English language. Similarly, compressed data can only be understood if the decoding method is known by the receiver.

Compression is useful because it helps reduce the consumption of expensive resources, such as hard disk space or transmission bandwidth. On the downside, compressed data must be decompressed to be used, and this extra processing may be detrimental to some applications. For instance, a compression scheme for video may require expensive hardware for the video to be decompressed fast enough to be viewed as it's being decompressed (the option of decompressing the video in full before watching it may be inconvenient, and requires storage space for the decompressed video). The design of data compression schemes therefore involves trade-offs among various factors, including the degree of compression, the amount of distortion introduced (if using a lossy compression scheme), and the computational resources required to compress and uncompress the data.

Computer science

Computer science (or computing science) is the study of the theoretical foundations of information and computation, and of practical techniques for their implementation and application in computer systems.^[1][2][3] It is frequently described as the systematic study of algorithmic processes that describe and transform information; the fundamental question underlying computer science is, "What can be (efficiently) automated?"^[4] Computer science has many sub-fields; some, such as computer graphics, emphasize the computation of specific results, while others, such as computational complexity theory, study the properties of computational problems. Still others focus on the challenges in implementing computations. For example, programming language theory studies approaches to describing computations, while computer programming applies specific programming languages to solve specific computational problems, and human-computer interaction focuses on the challenges in making computers and computations useful, usable, and universally accessible to people.

Electrical engineering

Electrical engineering, sometimes referred to as electrical and electronic engineering, is a field of engineering that deals with the study and application of electricity, electronics and electromagnetism. The field first became an identifiable occupation in the late nineteenth century after commercialization of the electric telegraph and electrical power supply. It now covers a range of subtopics including power, electronics, control systems, signal processing and 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 computers and integrated circuits.^[1] Alternatively, electrical engineers are usually concerned with using electricity to transmit energy, while electronic engineers are concerned with using electricity to transmit information.

Information technology ('IT)

Information technology ('IT), as defined by the Information Technology Association of America (ITAA), is "the study, design, development, implementation, support or management of computer-based information systems, particularly software applications and computer hardware."^[1] IT deals with the use of electronic computers and computer software to convert, store, protect, process, transmit, and securely retrieve information.

Today, the term information technology has ballooned to encompass many aspects of computing and technology, and the term has become very recognizable. The information technology umbrella can be quite large, covering many fields. IT professionals perform a variety of duties that range from installing applications to designing complex computer networks and information databases. A few of the duties that IT professionals perform may include data management, networking, engineering computer hardware, database and software design, as well as the management and administration of entire systems.

Computer Engineering

Computer Engineering (also called Electronic and Computer Engineering or Computer Systems Engineering) is a discipline that combines elements of both Electrical Engineering and Computer Science.^[1] Computer engineers usually have training in electrical engineering, software design and hardware-software integration instead of only software engineering or electrical engineering. Computer engineers are involved in many aspects of computing, from the design of individual microprocessors, personal computers, and supercomputers, to circuit design. This engineering monitors the many subsystems in motor vehicles.^[2]Usual tasks involving computer engineers include writing software and firmware for embedded microcontrollers, designing VLSI chips, designing analog sensors, designing mixed signal circuit boards, and designing operating systems.Computer engineers are also suited for robotics research,^{[citation needed]} which relies heavily on using digital systems to control and monitor electrical systems like motors, communications, and sensors.

Digital signal processing (DSP)

Digital signal processing (DSP) is concerned with the representation of the signals by a sequence of numbers or symbols and the processing of these signals. Digital signal processing and analog signal processing are subfields of signal processing. DSP includes subfields like: audio and speech signal processing, sonar and radar signal processing, sensor array processing, spectral estimation, statistical signal processing, digital image processing, signal processing for communications, biomedical signal processing, seismic data processing, etc.

Since the goal of DSP is usually to measure or filter continuous real-world analog signals, the first step is usually to convert the signal from an analog to a digital form, by using an analog to digital converter. Often, the required output signal is another analog output signal, which requires a digital to analog converter. Even if this process is more complex than analog processing and has a discrete value range, the stability of digital signal processing thanks to error detection and correction and being less vulnerable to noise makes it advantageous over analog signal processing for many, though not all, applications. ^[1]

Media (communication)

The beginning of human communication through artificial channels, i.e. not vocalization or gestures, goes back to ancient cave paintings, drawn maps, and writing.

The Persian Empire (centred around present-day Iran) played an important role in the field of communication. They devised what might be described as the first real mail or postal system, which is said to have been developed by the Persian emperor Cyrus the Great (c. 550 BC) after his conquest of Media. The role of the system as an intelligence gathering apparatus is well documented, and the service was (later) called angariae, a term that in time turned to indicate a tax system. The Old Testament (Esther, VIII) makes mention of this system: Ahasuerus, king of Medes, used couriers for communicating his decisions. Herodotus described the system in the following manner:^[4]

"It is said that as many days as there are in the whole journey, so many are the men and horses that stand along the road, each horse and man at the interval of a day’s journey; and these are stayed neither by snow nor rain nor heat nor darkness from accomplishing their appointed course with all speed."

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Democracy Data & Communications, LLC (DDC) is a leading provider of public affairs services and solutions, offering unparalleled strategic expertise, industry-leading technology solutions, and complete communications services. The firm, based in Alexandria, Virginia, offers a comprehensive approach to public affairs with expertise in grassroots, PACs, communications, membership development, fundraising, GOTV, and more.

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OnPoint's services include grasstops recruitment, community-based earned media, online awareness and recruitment, stakeholder mobilization, public education, and advocate development.

Electronic Communication

An electronic communication network (ECN) is the term used in financial circles for a type of computer system that facilitates trading of financial products outside of stock exchanges. The primary products that are traded on ECNs are stocks and currencies. ECNs came into existence in 1998 when the SEC authorized their creation. ECNs increase competition among trading firms by lowering transaction costs, giving clients full access to their order books, and offering order matching outside of traditional exchange hours.

Technology

Technology is a broad concept that deals with an animal species' usage and knowledge of tools and crafts, and how it affects an animal species' ability to control and adapt to its environment. Technology is a term with origins in the "technologia", "τεχνολογία" — "techne", "τέχνη" ("craft") and "logia", "λογία" ("saying").^[1] However, a strict definition is elusive; "technology" can refer to material objects of use to humanity, such as machines, hardware or utensils, but can also encompass broader themes, including systems, methods of organization, and techniques. The term can either be applied generally or to specific areas: examples include "construction technology", "medical technology", or "state-of-the-art technology".

The human race's use of technology began with the conversion of natural resources into simple tools. The prehistorical discovery of the ability to control fire increased the available sources of food and the invention of the wheel helped humans in travelling in and controlling their environment. Recent technological developments, including the printing press, the telephone, and the Internet, have lessened physical barriers to communication and allowed humans to interact on a global scale. However, not all technology has been used for peaceful purposes; the development of weapons of ever-increasing destructive power has progressed throughout history, from clubs to nuclear weapons.

Aircraft marshalling

Aircraft marshalling is visual signalling between ground personnel and pilots on an airport, aircraft carrier or helipad.

Marshalling is one-on-one visual communication and a part of aircraft ground handling. It may be as an alternative to, or additional to, radio communications between the aircraft and air traffic control, The usual attire of a marshaller is a reflecting safety vest, a helmet with acoustic earmuffs, and illuminated beacons or gloves.

At airports, the marshaller signals the pilot to keep turning, slow down, stop, and shut down engines, leading the aircraft to its parking stand or to the runway. Sometimes, the marshaller indicates directions to the pilot by driving a "Follow-Me" car (usually a yellow van or pick-up truck with a checkerboard pattern) prior to disembarking and resuming signalling. This, however, is not an industry standard.

Radar

Radar is a system that uses electromagnetic waves to identify the range, altitude, direction, or speed of both moving and fixed objects such as aircraft, ships, motor vehicles, weather formations, and terrain. The term RADAR was coined in 1941 as an acronym for radio detection and ranging.^[1][2][3] The term has since entered the English language as a standard word, radar, losing the capitalization. Radar was originally called RDF (Radio Direction Finder) in the United Kingdom.

A radar system has a transmitter that emits either microwaves or radio waves that are reflected by the target and detected by a receiver, typically in the same location as the transmitter. Although the signal returned is usually very weak, the signal can be amplified. This enables radar to detect objects at ranges where other emissions, such as sound or visible light, would be too weak to detect. Radar is used in many contexts, including meteorological detection of precipitation, measuring ocean surface waves, air traffic control, police detection of speeding traffic, and by the military.

Air Force Communication

The Air Force Communications Agency (AFCA) is a United States Air Force field operating agency of the Office of Warfighting Integration and Chief Information Officer. The agency was established on June 13, 1996 and is headquartered at Scott Air Force Base, Illinois. As of December 2005, AFCA has 116 officers, 140 enlisted, and 304 civilians.^{[citation needed]}

The agency was planned to be discontinued on 1 Oct 2008, concurrent with the establishment of Air Force Cyber Command. The AFCA was to be redesignated as the Twenty-Fourth Air Force.

Telecommunication

Telecommunication is the assisted transmission of signals over a distance for the purpose of communication. In earlier times, this may have involved the use of smoke signals, drums, semaphore, flags or heliograph. In modern times, telecommunication typically involves the use of electronic devices such as the telephone, television, radio or computer. Early inventors in the field of telecommunication include Alexander Graham Bell, Guglielmo Marconi and John Logie Baird. Telecommunication is an important part of the world economy and the telecommunication industry's revenue was estimated to be $1.2 trillion in 2006.