omniomni/omni-engineering huggingface dataset:
Crossed-field amplifier. A crossed-field amplifier (CFA) is a specialized vacuum tube, first introduced in the mid-1950s and frequently used as a microwave amplifier in very-high-power transmitters.

Raytheon engineer William C. Brown's work to adapt magnetron principles to create a new broadband amplifier is generally recognized as the first CFA, which he called an Amplitron. Other names that are sometimes used by CFA manufacturers include Platinotron or Stabilotron.

A CFA has lower gain and bandwidth than other microwave amplifier tubes (such as klystrons or traveling-wave tubes); but it is more efficient and capable of much higher output power.

Peak output powers of many megawatts and average power levels of tens of kilowatts can be achieved, with efficiency ratings over 70 percent. Their current use is in satellite ground stations and deep space communications networks.

Operation 

A CFA's electric and magnetic fields are perpendicular to each other ("crossed fields"). This is the same type of field interaction used in a magnetron; as a result, the two devices share many characteristics (such as high peak power and efficiency), and they have similar physical appearances. However, a magnetron is an oscillator, and a CFA is an amplifier (although a CFA can be driven to oscillate by application of improper low voltages as can any amplifier); a CFA's RF circuit (or slow-wave structure) is similar to that in a coupled-cavity TWT.

The CFA has the useful property that when power is shut off, the input simply passes to the output with little loss. This avoids the need for RF bypass switching in the event of failure.

Two CFAs can be connected sequentially with only one powered; if it fails, power can be removed from the primary tube and applied to the secondary as a backup. This approach with built-in redundancy was used on the S-band downlink transmitter on the Apollo Lunar Module, where high efficiency and reliability were needed.

A large negative voltage is placed on the green electrode in the center, and a large magnetic field is directed perpendicular to the page. This forms a thin spinning disk of electrons with a flow pattern like spinning water as it drains from a sink or toilet. A slow-wave structure is located above and below the spinning disk of electrons. Electrons flow much slower than the speed of light, and the slow wave structure reduces the velocity of the input RF enough to match the electron velocity.

The RF input is introduced into the slow wave structure. The alternating microwave field causes the electrons to speed up and slow down alternately. These disturbances grow larger as electrons spiral around the device, and electrons slow down as the RF energy grows. This produces amplification.

There is a small amount of RF feedback from output to input. This creates a slight random phase jitter when the device is pulsed.

References

Valve amplifiers
Microwave technology
American inventions
AIV. AIV may refer to:

Aimco, NYSE symbol AIV, an American operator of apartment communities
AIV fodder, a kind of acidified silage
Bavarian A IV, an 1852 German steam locomotive model
George Downer Airport (IATA: AIV) serving Aliceville, Alabama, USA
Panoz AIV Roadster, an American automobile
Angiotensin IV  (angiotensin 4)
Frederick Bramwell. Sir Frederick Joseph Bramwell, 1st Baronet FRS FRSA (17 March 1818 – 30 November 1903) was a British civil and mechanical engineer. He became a Fellow of the Royal Society in 1873 and served as president of the Institution of Civil Engineers between December 1884 and May 1886 and the president of the British Association for the Advancement of Science in 1888. He was knighted in 1881 and created a baronet on 25 January 1889.

Bramwell trained as an engineer and studied steam propulsion. In 1843 he constructed a locomotive for the Stockton and Darlington Railway; set up his own business concentrating on legal and consultative work (1853). He was the first engineer to practise as a technical advocate and later was adviser to the London water companies.

Family

He was the son of George Bramwell, a partner in Dorrien and Co. Bankers, and his wife Harriet, and the younger brother of Sir George William Wilshere Bramwell. He married on 29 March 1847, Harriet Leonara Frith (his cousin), daughter of Joseph Frith. There were three daughters to the marriage, with Eldred marrying the scientist, Sir Victor Horsley.

Bramwell died of a cerebral haemorrhage on 30 November 1903, in London, and was buried at Hever, Kent.

Works
 
 Our big guns (1886, address to the Birmingham and Midland Institute) from his work as a civilian member of the Ordnance Committee.

References

External links
 
 
 

1818 births
1903 deaths
British mechanical engineers
Presidents of the Institution of Civil Engineers
Presidents of the Smeatonian Society of Civil Engineers
Fellows of the Royal Society
Baronets in the Baronetage of the United Kingdom
Presidents of the British Science Association
Knights Bachelor
Called subscriber identification. A called subscriber identification (abbreviated CSID) is a string that identifies a specific fax machine as the recipient of a fax.

This string (typically less than 40 characters) is usually a combination of the fax machine's telephone number and identification of the fax machine's user.

Origins 
The CSID (and related TSID) are part of the modern landline fax specification. The CSID is often the same as the same machine's transmitting subscriber identification (TSID). A CSID and TSID are usually programmed into a fax machine when the machine is set up.

How it works 
When a fax machine receives a fax, it sends its CSID to the transmitting machine. The CSID is displayed on the sending fax machine and is usually recorded in the transmitting machine's log of sent faxes and printed on a report or confirmation of the fax transmission. This helps to confirm that the fax is being sent to the correct recipient.

Computer software sometimes emulates the functions of a fax machine.

A CSID and TSID are programmed into the software when it is configured. The software uses them when it sends or receives faxes.

References

See also
Caller ID
Transmitting Subscriber Identification (TSID)

Fax
I, Robot (Cory Doctorow). I, Robot is a science-fiction short story by Cory Doctorow published April 15, 2005.

According to Doctorow's website:

In spring 2004, in the wake of Ray Bradbury pitching a tantrum over Michael Moore appropriating the title of Fahrenheit 451 to make Fahrenheit 9/11, I conceived of a plan to write a series of stories with the same titles as famous sf shorts, which would pick apart the totalitarian assumptions underpinning some of sf's classic narratives.

The story is influenced by Isaac Asimov's robot series and by George Orwell's 1984.

The story is set in the type of police state needed to ensure that only one company is allowed to make robots, and only one type of robot is allowed.

The story is set in a future Toronto, part of the United North American Trading Sphere, and follows single father detective Arturo Icaza de Arana-Goldberg while he tries to track down his missing teenage daughter. The detective is a bit of an outcast because his wife defected to Eurasia, a rival Superpower.

Reception
The story won the Locus Award for Best Novelette and was a finalist for the 2006 Hugo Award for Best Novelette.

References

External links
The story is also available as a free online ebook under a Creative Commons License

2005 short stories
Science fiction short stories
2000s science fiction works
Hamburger Hochbahn. Hamburger Hochbahn AG (HHA), founded in 1911, operates the underground system and large parts of the bus system in Hamburg, Germany. Its name comes from the initial name given to the Hamburg metro system, Hochbahn (German: elevated railway).

History 

The HHA was founded by Siemens & Halske and AEG as a consortium on 27 May 1911. The first chairman was Albert Ballin.

From 1919 until 1978, the HHA operated a large tram network, and from 5 December 1921 the HHA also operated the first motor buses in Hamburg. After the acquisition of the Straßen-Eisenbahn-Gesellschaft (SEG) in 1919 and the Hamburg-Altonaer-Centralbahngesellschaft AG in 1923, the HHA had a rolling stock of 865 power cars and 930 trailers by 1928. The length of tracks was 217.33 km. In 1970 the length of the lines were only 82.7 km, in 1978 they were 89.5 km with 80 stations.

In 1965, HHA was one of the founding members of the Hamburger Verkehrsverbund (HVV).

Operations 

HHA operates about 111 bus routes and four underground lines. In spite of the "U" for "underground", large portions, especially outside the inner city, run on the surface. Some parts of the underground, notably along the banks of River Elbe in the city centre, are elevated (hence the name "Hochbahn", "elevated railway").

Subsidiaries 
BeNEX GmbH is the holding company for public transport corporations outside of Hamburg. BeNex owns railway and bus companies. In August 2007, the UK listed investment firm International Public Partnerships Limited (then known as Babcock & Brown Public Partnerships) acquired 49% of BeNEX.

Through BeNEX the Hamburger Hochbahn owns 25.1% of the Metronom Eisenbahngesellschaft, a company operating commuter trains in northern Germany. Nordbahn Eisenbahngesellschaft, with Neumünster - Bad Segeberg - Bad Oldesloe railway in Schleswig-Holstein, is owned in joint venture with the AKN railway. Among others there are also the East German Railway plc (; 50% ownership) and the Cantus Verkehrsgesellschaft, both joint ventures with other corporations.

Notes
 The information in this article is based on its German equivalent

External links

Official website 
 

Transport in Hamburg
Hamburg U-Bahn
Railway companies established in 1911
Companies based in Hamburg
Public transport operators of Germany
German companies established in 1911
Room synchronization. The room synchronization technique is a form of concurrency control in computer science.

The room synchronization problem involves supporting a set of m mutually exclusive "rooms" where any number of users can execute code simultaneously in a shared room (any one of them), but no two users can simultaneously execute code in separate rooms.

Room synchronization can be used to implement asynchronous parallel queues and stacks with constant time access (assuming a fetch-and-add operation).

References
 G.E. Blelloch, P. Cheng, P.B. Gibbons, Room synchronizations, Annual ACM Symposium on Parallel Algorithms and Architectures 2001, 122–133

See also 
 Monitor (synchronization).
 The Single Threaded Apartment Model in Microsoft's Component Object Model#Threading, as used by Visual Basic.

Concurrency control
Hippolyte Pixii. Hippolyte Pixii (1808–1835) was an instrument maker from Paris, France. In 1832 he built an early form of alternating current electrical generator, based on the principle of electromagnetic induction discovered by Michael Faraday. Pixii's device was a spinning magnet, operated by a hand crank, where the north and south poles passed over a coil with an iron core, and thus classified as a magneto. A current pulse was produced each time a pole passed over the coil. He also found that the current direction changed when the north pole passed over the coil after the south pole. Later, acting on a suggestion by André-Marie Ampère, other results were obtained by introducing a commutator which produced a pulsating direct current. At that time direct current was preferable to alternating current. Although Pixii did not fully understand electromagnetic induction, his device led to more sophisticated devices being constructed.
A reproduction of Pixii's electrical generator can be admired at the Ampère Museum, close to Lyon.

See also  
 Alternating current

References

19th-century French engineers
People associated with electricity
1808 births
1835 deaths
Engineers from Paris
Formula Lightning. Formula Lightning was an electric car open-wheel, open cockpit formula racing series for University engineering programs that ran from 1994 to 2004 in the United States. The series was sponsored by ABB and a number of local and regional electric companies. For much of the duration of the series, the races were organized by Electric Vehicles Technology Competitions (EVTC) and sanctioned by SCCA Pro Racing. 

The motivation behind the series was to generate excitement amongst the public about electric vehicles.  The hope was that focusing on high speed racing, rather than an endurance event, would get fans of motorsports like NASCAR and IndyCar to think favorably about electric vehicle technology.  The race organizers also sought to inspire and train a generation of undergraduate engineers to become electric vehicle designers of the future. 

The basic chassis of the vehicles was standardized and built by the Solar Electric Race Association (SERA).  Universities across the country purchased these identical rolling chassis and then designed, developed, and built the electric drive systems needed to race.  There were no changes allowed in the chassis design without majority approval of the Formula Lightning Owners Association. This ensured student teams could concentrate on the electric drive without the necessity of designing specialized mechanical chassis components. 

The two predominant battery technologies used in the powertrains were lead-acid and nickel-cadmium. Most cars had somewhere around 1200 pounds of batteries, which were stored in the side-pods. The races were typically 25-50 miles long. Because of the speeds that the cars ran at and the state of battery technology at the time, more than one set of batteries were needed per race. Thus most teams planned at least one pit stop, which required 600 pounds of batteries to be removed from each side and replaced with a fully charged pack.

Professional drivers were hired to pilot the vehicles during the races and were able to reach speeds up to . The series competed on both oval tracks (including Indianapolis Raceway Park and Richmond International Raceway) and road course race tracks (including Burke Lakefront Airport and Firebird Raceway in Phoenix). 

The first race was held in July 1994 in support of the Grand Prix of Cleveland CART race with the University of Notre Dame winning the event.  Throughout the decade-long series a number of universities participated including Bowling Green State University, IUPUI, University of Oklahoma, Ohio State University, Kettering University, and Arizona State University. The final official series race was held in October 2004 at Mid-Ohio Sports Car Course. Ohio State University was the leading series champion.

The race series stands as an important precursor to Formula E and the rise of other electric motorsports in the 2010s and 2020s, that happened alongside the broader spread of electric powered passenger vehicles.

References

Auto racing series in the United States
Lightning
Lightning
Recurring sporting events established in 1994
Recurring events disestablished in 2004
Defunct auto racing series
Electric vehicles
Abampere. The abampere (abA), also called the biot (Bi) after Jean-Baptiste Biot, is the derived electromagnetic unit of electric current in the emu-cgs system of units (electromagnetic cgs). One abampere corresponds to ten amperes in the SI system of units. An abampere of current in a circular path of one centimeter radius produces a magnetic field of 2π oersteds at the center of the circle. 

The name abampere was introduced by Kennelly in 1903 as a short name for the long name (absolute) electromagnetic cgs unit of current that was in use since the adoption of the cgs system in 1875. The abampere was coherent with the emu-cgs system, in contrast to the ampere, the practical unit of current that had been adopted too in 1875.

The emu-cgs (or "electromagnetic cgs") units are one of several systems of electromagnetic units within the centimetre–gram–second system of units; others include esu-cgs, Gaussian units, and Heaviside–Lorentz units. In these other systems, the abampere is not one of the units; the "statcoulomb per second" or statampere is used instead.

The other units in this system related to the abampere are: 

 abcoulomb – the charge that passes in one second through any cross section of a conductor carrying a steady current of one abampere
 abhenry – the self-inductance of a circuit or the mutual inductance of two circuits in which the variation of current at the rate of one abampere per second results in an induced electromotive force of one abvolt  
 abohm – the resistance of a conductor that, with a constant current of one abampere through it, maintains between its terminals a potential difference of one abvolt

See also 
 List of metric units

Notes

References

Units of electric current
Centimetre–gram–second system of units
Interruptible operating system. An interruptible operating system  is an operating system with ability to handle multiple interrupts concurrently, or in other words, which allow interrupts to be interrupted.

Concurrent interrupt handling essentially mean concurrent execution of kernel code and hence induces the additional complexity of concurrency control in accessing kernel datastructures.

It also means that the system can stop any program that is already running, which is a feature on nearly all modern operating systems.

See also
 Operating system
 Operating System Projects

Interrupts
Application-oriented networking. Application-oriented networking (AON) involves network devices designed to aid in computer-to-computer application integration. Application-oriented networks are sometimes called "intelligent networks" or "content-based routing networks" and they are generally  network technology that can use the content of a network packet or message to take some sort of action.

Application-oriented networking was popularized by Cisco Systems in response to increasing use of XML messaging (combined with related standards such as XSLT, XPath and XQuery) to link miscellaneous applications, data sources and other computing assets. Most Application-Orientated Networks manipulate structured data based in a human-readable format like XML.

Many of the operations required to mediate between applications, or to monitor their transactions, can be built into network devices that are optimized for the purpose.

The rules and policies for performing these operations, also expressed in XML, are specified separately and downloaded as required. Cisco has adopted the AON acronym as the name of a family of products that function in this way.

Routing decisions
During the rise of the internet many routing decisions were made at layer 4 i.e. based on the TCP/IP address and/or the port number. Application-oriented networks work at layer 7 of the OSI stack and because they can examine the content of the message they can make routing decisions based on many different criteria including such things as the value of the purchase order or the ship date.

See also
Enterprise Application Integration

References

External links
XML Security in Netscaler 
Definition

Networking hardware
Telecommunications
Statistical Lab. The computer program Statistical Lab (Statistiklabor) is an explorative and interactive toolbox for statistical analysis and visualization of data. It supports educational applications of statistics in business administration, economics, social sciences and humanities. The program is developed and constantly advanced by the Center for Digital Systems of the Free University of Berlin. Their website states that the source code is available to private users under the GPL.  So if a commercial user wishes to obtain a copy, then they must do so indirectly, from a private user who already has a copy (any of their employees will do).

Simple or complex statistical problems can be simulated, edited and solved individually with the Statistical Lab. It can be extended by using external libraries. Via these libraries, it can also be adapted to individual and local demands like specific target groups. The versatile graphical diagrams allow demonstrative visualization of underlying data.

The Statistical Lab is the successor of Statistik interaktiv!. In contrast to the commercial SPSS the Statistical Lab is didactically driven. It is focused on providing facilities for users with little statistical experience. It combines data frames, contingency tables, random numbers, matrices in a user friendly virtual worksheet. This worksheet allows users to explore the possibilities of calculations, analysis, simulations and manipulation of data.

For mathematical calculations, the Statistical Lab uses the R package, which is a free implementation of the language S Plus (originally developed by Bell Laboratories).

See also
 R interfaces

References

External links
Homepage of the Statistical Lab - in English
Statistical Lab Tutorial for newbies - English versions available
forum for Statistical Lab users - bilingual English and German
Tigris.org Source-Code of the Statistical Lab (discontinued, source-code now available in the download-area of the main pages: )
Homepage of the Center for Digital Systems

Statistical software
Windows-only freeware
Ranger (yacht). Ranger was a J-class racing yacht that successfully defended the 1937 America's Cup, defeating the British challenger Endeavour II 4–0 at Newport, Rhode Island. It was the last time J-class yachts would race for the America's Cup.

Design
Harold Stirling Vanderbilt funded construction of Ranger, and she was launched on May 11, 1937. She was designed by Starling Burgess and Olin Stephens, and constructed by Bath Iron Works. Stephens would credit Burgess with actually designing Ranger, but the radical departure from the heavy displacement sailing yachts was attributal to Stephens himself who had first used the design in Dorade, winner of the 1931 Trans-Atlantic Race. Geerd Hendel, Burgess's chief draftsman, also had a hand in drawing many of the plans.

The hull was all-steel welded by a shielded arc process with a weight-saving aluminum, arc-welded, mast counterbalanced with a 110-ton lead keel supported by an arc-welded steel keel plate.

Ranger was constructed according to the Universal Rule that constrained the various dimensions of racing yachts, such as sail area and length. Often referred to as the "super J", Ranger received a rating of 76, the maximum allowed while still adhering to the Universal Rule.

Career
Ranger raced Endeavour II in the 1937 America's Cup, winning 4–0.

Ranger was scrapped between either 1941 or 1946 – sources differ.

Replica

Construction of a replica of Ranger was started at Danish Yacht Boatyard (by Royal Denship) in early 2002 and was completed in late December 2003. The original designs were used as the basis for the new boat but were updated to conform to the latest safety regulations and the requirement of the owner to cross oceans in comfort.

References

External links
 

J-class yachts
Individual sailing vessels
America's Cup defenders
Yachts of New York Yacht Club members
Sailing yachts designed by William Starling Burgess
Sailing yachts built in the United States
Sailboat type designs by Olin Stephens
Sailboat type designs by American designers
1930s sailing yachts
List of British railway-owned locomotive builders. Many early locomotive works disappeared as railways merged or they became simply motive power depots. Some, like Bromsgrove, made only one or two new locomotives but, for  even the largest, overhaul and repair of the existing fleet was the main activity.

See also List of locomotive builders and List of early British private locomotive manufacturers

Sources
 Atkins, P., (1999) The Golden Age of Steam Locomotive Building, Penrhyn: Atlantic Transport Publications
 Larkin, E.J., Larkin, J.G., (1988) The Railway Workshops of Great Britain 1823–1986, Macmillan Press

 
 
British railway-owned locomotive builders