omniomni/omni-engineering huggingface dataset:
Invensys Rail Group. Invensys Rail Group was a division of Invensys, a UK-based multinational engineering company. It was a designer, manufacturer and integrator of railway equipment, including automation, signalling and controls.  The group was headquartered in Chippenham, Wiltshire, and , had over 2,750 employees in 14 locations internationally. 
It operated through four companies: 
 Invensys Rail Dimetronic (Spain, Portugal and Latin America); 
 Westinghouse Rail Systems (UK); and 
 Invensys Rail Systems Australia incorporating Westinghouse Signals Australia and Foxboro Transportation, now known collectively as WRSA (Westinghouse Rail Systems Australia).

Westinghouse Rail Systems Ltd (WRSL) (UK) was previously known as Westinghouse Signals Ltd and before that was part of Westinghouse Brake and Signal Company, named after inventor George Westinghouse.

The other part of Westinghouse Brake and Signal Company, Westinghouse Brakes Ltd, was sold by Invensys to Knorr-Bremse, and has since left the Chippenham site to set up in the nearby town of Melksham.

On 28 November 2012, Invensys agreed to sell its rail arm to Siemens AG for £1.7bn. The sale was completed on 2 May 2013, and the group was amalgamated with the Siemens’ Rail Automation Business Unit in the Mobility and Logistics Division, which in turn a part of Infrastructure & Cities sector of Siemens.

References

External links

Rail lines: Tracking developments in rail systems – group blog
http://www.railpage.com.au/news-11770.htm
http://www.news.com.au/business/breaking-news/siemens-buys-invensys-rail-automation-arm/story-e6frfkur-1226526269654
Reuters
http://www.railwaygazette.com/news/single-view/view/siemens-agrees-to-buy-invensys-rail.html

Rail industry
Railway infrastructure companies
Pye Green BT Tower. Pye Green BT Tower is a  tall telecommunication tower built of reinforced concrete at Pye Green, Staffordshire, England. Standing on the far southern edge of Cannock Chase, it is one of 14 telecommunication towers in the United Kingdom built of reinforced concrete. Pye Green was constructed as part of the British Cold War "Backbone" radio communications network.

Its combination of elevation and height give it line-of-sight to the BT Tower in Birmingham and Sutton Common in Cheshire.

Services available

Analogue radio (FM VHF)

Digital radio (DAB)

See also 
British Telecom microwave network
Telecommunications towers in the United Kingdom

References 
 
 Campbell, D., 1983. War Plan UK, p243, p245. Paladin edition. .
 Laurie, P., 1983. Beneath the City Streets, p. 243, p. 246. Granada edition. .
 The National Archives (UK), 1956–1962. Proposed relay station sites for the General Post Office ("The Backbone Scheme"). File No. COU1/38.
 Fox, S., and Lamont, R., 2003. The Towers of Backbone.

External links 
The Transmission Gallery: photographs, coverage maps and information

Towers in Staffordshire
Cannock Chase
Communication towers in the United Kingdom
British Telecom buildings and structures
Transmitter sites in England
Super PI. Super PI is a computer program that calculates pi to a specified number of digits after the decimal point—up to a maximum of 32 million. It uses Gauss–Legendre algorithm and is a Windows port of the program used by Yasumasa Kanada in 1995 to compute pi to 232 digits.

Significance
Super PI is popular in the overclocking community, both as a benchmark to test the performance of these systems  and as a stress test to check that they are still functioning correctly.

Credibility concerns
The competitive nature of achieving the best Super PI calculation times led to fraudulent Super PI results, reporting calculation times faster than normal. Attempts to counter the fraudulent results resulted in a modified version of Super PI, with a checksum to validate the results. However, other methods exist of producing inaccurate or fake time results, raising questions about the program's future as an overclocking benchmark.

Super PI utilizes x87 floating point instructions which are supported on all x86 and x86-64 processors, current versions which also support the lower precision Streaming SIMD Extensions vector instructions.

References

External links
 
 

Benchmarks (computing)
Pi-related software
Armstrong Electric. Armstrong Electric was a manufacturer of electric automobiles in Bridgeport, Connecticut.  The company was founded by inventor, William Armstrong, and produced cars from 1885 through 1902.

Present day
It was reported that the Maple Street factory used by Armstrong to build its first car could be used again used for automobile manufacture by AC Cars.

The original car has recently been rebuilt in England, and has run for the first time in over 100 years.  It is currently on show in a Victorian vehicle collection at a Sussex country park.

https://www.hemmings.com/blog/2016/03/14/perhaps-the-worlds-first-hybrid-an-1896-armstrong-sells-for-483400-at-amelia-island/

References

Electric vehicles introduced in the 19th century
Defunct motor vehicle manufacturers of the United States
Defunct companies based in Connecticut
Companies based in Bridgeport, Connecticut
Vehicle manufacturing companies established in 1885
Vehicle manufacturing companies disestablished in 1902
Vintage vehicles
1885 establishments in Connecticut
1902 disestablishments in Connecticut
Vital Product Data. Vital Product Data (VPD)  is a collection of configuration and informational data associated with a particular set of hardware or software. VPD stores information such as part numbers, serial numbers, and engineering change levels. Not all devices attached to a system will provide VPD, but it is often available from PCI and SCSI devices.  Parallel ATA and USB devices also provide similar data, but do not refer to it as VPD.

VPD data is typically burned onto EEPROMs associated with various hardware components, or can be queried through attached I2C buses. It is used by firmware (for example, OpenFirmware) to determine the nature of the system hardware, and to shield the operation of the firmware from minor changes and variations of hardware implementations within a given machine model number.

AIX
In IBM's AIX operating system, VPD also refers to a subset of database tables in the Object Data Manager (ODM) obtained from either the Customized VPD object class or platform specific areas, therefore the VPD and ODM terms are sometimes referred to interchangeably. 
 command can be used in AIX to get the VPD.

lscfg [-v] [-p] [-s] [-l Name]

Other Unix-like systems
Package dmidecode provides commands vpddecode, biosdecode, and dmidecode, which can display hardware Vital Product Data. This package is available for many Unix-like operating systems.

See also
Organizationally unique identifier
World Wide Name

References

Further reading
 PCI System Architecture (PC System Architecture Series), 10 Jun 1999, MindShare Inc., Tom Shanley, Don Anderson, 

Identifiers
IBM AIX
Solid-state laser. A solid-state laser is a laser that uses a gain medium that is a solid, rather than a liquid as in dye lasers or a gas as in gas lasers. Semiconductor-based lasers are also in the solid state, but are generally considered as a separate class from solid-state lasers, called laser diodes.

Solid-state media

Generally, the active medium of a solid-state laser consists of a glass or crystalline "host" material, to which is added a "dopant" such as neodymium, chromium, erbium, thulium or ytterbium. Many of the common dopants are rare-earth elements, because the excited states of such ions are not strongly coupled with the thermal vibrations of their crystal lattices (phonons), and their operational thresholds can be reached at relatively low intensities of laser pumping.

There are many hundreds of solid-state media in which laser action has been achieved, but relatively few types are in widespread use. Of these, probably the most common is neodymium-doped yttrium aluminum garnet (Nd:YAG). Neodymium-doped glass (Nd:glass) and ytterbium-doped glasses or ceramics are used at very high power levels (terawatts) and high energies (megajoules), for multiple-beam inertial confinement fusion.

The first material used for lasers was synthetic ruby crystals. Ruby lasers are still used for a few applications, but they are no longer common because of their low power efficiencies. At room temperature, ruby lasers emit only short pulses of light, but at cryogenic temperatures they can be made to emit a continuous train of pulses.

The second solid-state gain medium was uranium-doped calcium fluoride. Peter Sorokin and Mirek Stevenson at IBM's laboratories in Yorktown Heights (US) experimented with this material in the 1960s and achieved lasing at 2.5 μm shortly after Maiman's ruby laser.

Some solid-state lasers can be made tunable by using intracavity etalons, prisms, gratings, or a combination of these. Titanium-doped sapphire is widely used for its broad tuning range, 660 to 1080 nanometers. Alexandrite lasers are tunable from 700 to 820 nm and yield higher-energy pulses than titanium-sapphire lasers because of the gain medium's longer energy storage time and higher damage threshold.

Pumping

Solid state lasing media are typically optically pumped, using either a flashlamp or arc lamp, or by laser diodes. Diode-pumped solid-state lasers tend to be much more efficient and have become much more common as the cost of high-power semiconductor lasers has decreased.

Mode locking

Mode locking of solid-state lasers and fiber lasers has wide applications as large-energy ultra-short pulses can be obtained. There are two types of saturable absorbers that are widely used as mode lockers: SESAM, and SWCNT. Graphene has also been used. These materials use a nonlinear optical behavior called saturable absorption to make a laser create short pulses.

Applications

Solid state lasers are used in research, medical treatment, and military applications, among others.

See also
 Disk laser
 Laser construction
 Solid-state dye lasers

References
Sun Java System. Sun Java System was a brand used by Sun Microsystems to market computer software. The Sun Java System brand superseded the Sun ONE brand in September 2003.  There are two major suites under this brand, the Sun Java Enterprise System suite of infrastructure software, and the Sun Java Desktop System graphical user environment.

Sun ONE brand

Sun ONE was a brand under which Sun Microsystems marketed server software products from 2002 to 2003. Sun ONE stood for Sun Open Net Environment.

The Sun ONE brand was primarily used for products that resulted after the dissolution of Sun's alliance with Netscape Communications Corporation, which was sold under the brand name of iPlanet. The name was also applied to other Sun software products such as Sun ONE Studio 8 and Sun ONE Active Server Pages 4.0. Products included:
Sun ONE Web Server
Sun ONE Web Proxy Server
Sun ONE Application Server
Sun ONE Messaging Server
Sun ONE Calendar Server
Sun ONE Directory Server

Sun ONE was introduced on April 15, 2002, to supersede the iPlanet brand name, following the end of the Sun-Netscape alliance. Sun ONE itself was superseded on September 16, 2003, by the Sun Java System brand.

Sun Java Enterprise System
The Sun Java Enterprise System is itself broken into smaller suites, which include:

Identity management services (Sun Java Identity Management Suite)
 Sun Java System Access Manager
 Sun Java System Identity Manager
 Sun Java System Role Manager
 Sun Java System Federation Manager
 Sun Java System Directory Server, formerly Sun ONE Directory Server and iPlanet Directory Server
 Sun Java System Directory Proxy Server

Business Integration - SOA (Sun Java Composite Application Platform Suite) 
 Sun Java ESB Suite
 Sun Java B2B Suite

Web and application services 
 Sun Java System Application Server (SJSAS), formerly Sun ONE Application Server
 Sun Java System Message Queue (SJSMQ), formerly Java Message Queue
 Sun Java System Web Server, formerly Sun ONE Web Server and iPlanet Web Server
 Sun Java System Web Proxy Server, formerly Sun ONE Web Proxy Server and iPlanet Web Proxy Server
 Sun Java System Messaging Server, formerly Sun ONE Messaging Server and iPlanet Messaging Server
 Sun Java System Calendar Server, formerly Sun ONE Calendar Server and iPlanet Calendar Server
 Sun Java System Service Registry

Portal services 
 Sun Java System Portal Server
 Sun Java System Portal Mobile Access
 Sun Java System Portal Remote Access

Availability services (Sun Java Availability Suite) 
 Sun Cluster
 Sun Cluster Agents
 Sun Cluster Geographic Edition
 Sun N1 Service Provisioning System

Development tools 
 Java Studio Enterprise
 Java Studio Creator

Sun Java Desktop System

References

External links
 Sun Java System Wiki
 Java ES Interoperability Space

Sun Microsystems software
GroovyLab. GroovyLab, formerly jLab, is a numerical computational environment implemented in Java. The main scripting engine of jLab is GroovySci, an extension of Groovy. Additionally, the interpreted J-Scripts (similar to MATLAB) and dynamic linking to Java class code are supported.

The jLab environment aims to provide a MATLAB/Scilab like scientific computing platform that is supported
by scripting engines implemented in the Java language.

In the current implementation of jLab there coexist two scripting engines:
 the interpreted j-Script scripting engine and
 the compiled Groovy scripting engine. The later (i.e. Groovy) seems to be the preferred  choice, since it is much faster, can execute directly Java code using only the familiar Java packaging rules, and is feature-rich language, i.e. Groovy enhanced with MATLAB style matrix operations and surrounding support environment.

See also 
 List of numerical-analysis software
 Comparison of numerical-analysis software

External links 
 https://github.com/sterglee/GroovyLab
 https://sourceforge.net/projects/groovylab/
 https://code.google.com/archive/p/jlabgroovy/

Numerical programming languages
Free mathematics software
Array programming languages
Bélády's anomaly. In computer storage, Bélády's anomaly is the phenomenon in which increasing the number of page frames results in an increase in the number of page faults for certain memory access patterns. This phenomenon is commonly experienced when using the first-in first-out (FIFO) page replacement algorithm. 
In FIFO, the page fault may or may not increase as the page frames increase, but in optimal and stack-based algorithms like LRU, as the page frames increase, the page fault decreases.
László Bélády demonstrated this in 1969.

Background
In common computer memory management, information is loaded in specific-sized chunks. Each chunk is referred to as a page. Main memory can hold only a limited number of pages at a time. It requires a frame for each page it can load. A page fault occurs when a page is not found, and might need to be loaded from disk into memory.

When a page fault occurs and all frames are in use, one must be cleared to make room for the new page. A simple algorithm is FIFO: whichever page has been in the frames the longest is the one that is cleared. Until Bélády's anomaly was demonstrated, it was believed that an increase in the number of page frames would always result in the same number of or fewer page faults.

Bélády's anomaly is unbounded
Bélády, Nelson and Shedler constructed reference strings for which FIFO page replacement algorithm produced nearly twice as many page faults in a larger memory than in a smaller one and they formulated the conjecture that 2 is a general bound.

In 2010, Fornai and Iványi showed that the anomaly is in fact unbounded and that one can construct a reference string to any arbitrary page fault ratio.

References

External links 
 Bélády's 1969 paper: An anomaly in space-time characteristics of certain programs running in a paging machine
 FIFO anomaly is unbounded. 
 Internet Problem Solving Contest Solutions – Problem L – Librarian

Memory management
Ethyl cyanoacrylate. Ethyl cyanoacrylate (ECA), a cyanoacrylate ester, is an ethyl ester of 2-cyano-acrylic acid. It is a colorless liquid with low viscosity and a faint sweet smell in pure form. It is the main component of cyanoacrylate glues and can be encountered under many trade names. It is soluble in acetone, methyl ethyl ketone, nitromethane, and methylene chloride. ECA polymerizes rapidly in presence of moisture.

Production
Ethyl cyanoacrylate is prepared by the condensation of formaldehyde with ethyl cyanoacetate:

This exothermic reaction affords the polymer, which is subsequently sintered, thermally "cracked" to give the monomer.  Alternatively, it can be prepared by the ethoxycarbonylation of cyanoacetylene.

Applications
Ethyl cyanoacrylate is used for gluing. 

In forensics, cyanoacrylate ester has excellent non-destructive impressioning abilities, which are especially important when lifting fingerprints from delicate evidence items, or when the prints could not be lifted using traditional means such as fingerprinting powder. The procedure involves heating the acrylate in a sealed chamber. Its fumes then react with deposited proteins that form into a white, stable, and clear print outlines. The resulting prints could be used 'as is' or enhanced further by staining them with darker pigments. Liquid bandage systems use the less toxic n-butyl and octyl cyanoacrylates.

Safety
In the U.S., the threshold limit value for ECA is 0.2 ppm.  It is a strong irritant to the lungs and eyes.

See also
 Cyanoacrylate
 Methyl cyanoacrylate
 Butyl cyanoacrylate
 Octyl cyanoacrylate

References

Ethyl esters
Monomers
Cyanoacrylate esters
Lachrymatory agents
Sweet-smelling chemicals
Cougar Helicopters. Cougar Helicopters (a VIH Aviation Group Company) is a St. John's based commercial helicopter company servicing offshore oil and gas fields off the coast of Newfoundland. Cougar has permanent facilities in St. John's and Halifax. The company is affiliated with Bristow Helicopters which has a financial stake in Cougar.

Services

Cougar Helicopters currently services platforms and ships located off Newfoundland in the:
 Hibernia oil field 
 Terra Nova oil field
 White Rose oil field 
 Hebron-Ben Nevis oil field

Fleet
As of May 2024, Cougar Helicopters operates a fleet of eight Sikorsky S-92A and one Bell 412EP.

Incidents and accidents

On 12 March 2009, Cougar Helicopters Flight 91, a Cougar Sikorsky S-92A helicopter carrying 18 passengers and crew en route to an oil platform off the coast of Newfoundland, ditched and sank in 178 metres of water. 17 of the 18 people on board died in the crash.

References

External links

 Cougar Helicopters
 VIH Aviation Group

Regional airlines of Atlantic Canada
Helicopter airlines
Companies based in St. John's, Newfoundland and Labrador
Radioisotope piezoelectric generator. A radioisotope piezoelectric generator (RPG) is a type of radioisotope generator that converts energy stored in radioactive materials into motion, which is used to generate electricity using the repeated deformation of a piezoelectric material. This approach creates a high-impedance source and, unlike chemical batteries, the devices will work at a very wide range of temperatures.

History
In 2002 researchers at Cornell University published and patented the first design.

Mechanism
A piezoelectric cantilever is mounted directly above a base of the radioactive isotope nickel-63. All of the radiation emitted as the millicurie-level nickel-63 thin film decays is in the form of beta radiation, which consists of electrons. As the cantilever accumulates the emitted electrons, it builds up a negative charge at the same time that the isotope film becomes positively charged. The beta particles essentially transfer electronic charge from the thin film to the cantilever. The opposite charges cause the cantilever to bend toward the isotope film. Just as the cantilever touches the thin-film isotope, the charge jumps the gap. That permits current to flow back onto the isotope, equalizing the charge and resetting the cantilever. As long as the isotope is decaying - a process that can last for decades - the tiny cantilever will continue its up-and-down motion. As the cantilever directly generates electricity when deformed, a charge pulse is released each time the cantilever cycles.

Radioactive isotopes can continue to release energy over periods ranging from weeks to decades. The half-life of nickel-63, for example, is over 100 years. Thus, a battery using this isotope might continue to supply useful energy for at least half that time. Researchers have demonstrated devices with about 7% efficiency with high frequencies of 120 Hz to low-frequency (every three hours) self-reciprocating actuators.

See also
Atomic battery
Betavoltaics
Thermionic converter
Optoelectric nuclear battery

References

Nuclear technology
Electric battery
Electrical generators
System 4. System 4 or System IV may refer to:
 Acorn System 4, the early minicomputer
 The fourth release of Classic Mac OS
 International Computers Limited#English Electric LEO Marconi (EELM), also known as ICL System 4
 Not-released Unix system between UNIX System III and UNIX System V
 STS-4 (Space Transportation System-4), the Space Shuttle mission

See also
 IBM System/4 Pi
IRF. IRF may refer to:

General
Impulse response function
Inertial reference frame
Information Retrieval Facility
Initial Reaction Force or Internal Response Force
Immediate Response Force
Institute of Space Physics (Sweden), (Institutet för rymdfysik)
Interferon regulatory factor (e.g. IRF6)
International Rectifier, New York Stock Exchange symbol IRF

Foundations/organizations
International Ranger Federation
International Rabbinic Fellowship
International Rogaining Federation
Islamic Research Foundation
International Rafting Federation
International Ringette Federation
International Road Federation

Computing
Intelligent Resilient Framework, Virtual Switch Chassis Aggregation
Tolsford Hill BT Tower. Tolsford Hill BT Tower is a telecommunication tower built of reinforced concrete at Tolsford Hill on the North Downs near Folkestone, Kent. Tolsford Hill BT Tower is one of the few British towers built of reinforced concrete and is 67.36 metres ( 221 ft) high.

See also
 British Telecom microwave network
 Telecommunications towers in the United Kingdom

References
 RSG: Features: The Towers of Backbone.

Communication towers in the United Kingdom
Towers in Kent
British Telecom buildings and structures
Transmitter sites in England