omniomni/omni-engineering huggingface dataset:
English pewter. While the term pewter covers a range of tin-based alloys, the term English pewter has come to represent a strictly-controlled alloy, specified by BSEN611-1 and British Standard 5140, consisting mainly of tin (ideally 92%), with the balance made up of antimony and copper.  Significantly, it is free of lead and nickel. Although the exact percentages vary between manufacturers, a typical standard for present-day pewter is approximately 91% tin, 7.5% antimony and 1.5% copper.

By the 15th century, the Worshipful Company of Pewterers controlled pewter constituents in England.  This company originally had two grades of pewter, but in the 16th century a third grade was added.  The first type, known as "fine metal", was used for tableware.  It consisted of tin with as much copper as it could absorb, which is about 1%.  The second type, known as "trifling metal" or "trifle", was used for holloware.  It is made up of fine metal with approximately 4% lead.  The last type of pewter, known as "lay" or "ley" metal, was used for items that were not in contact with food or drink.  It consisted of tin with 15% lead.  These three alloys were used, with little variation, until the 20th century.

Lead was removed from the composition in 1974, by BS5140, reinforced by the European directive BSEN611 in 1994.

Until the end of the 18th century, the only method of manufacture was by casting and the soldering of components. From the last quarter of the 18th century, improvement in alloys (e.g. britannia metal) and techniques allowed objects to be made from pewter by stamping and spinning.

Notes

References 

.

External links
 The Worshipful Company of Pewterers
 Victoria & Albert Museum: Pewter History

Fusible alloys
Tin alloys
Bromodifluoromethane. Bromodifluoromethane or Halon 1201 or FC-22B1 is a gaseous trihalomethane or a hydrobromofluorocarbon.

Synthesis
It can be prepared through the reaction of hydrogen and dibromodifluoromethane at temperature in range 400–600 °C.

Critical point data: Tc = 138.83 °C (411.98K); pc = 5.2MPa (51.32bar); Vc = 0.275dm3·mol−1.

Applications
Bromodifluoromethane was used as a refrigerant and in fire extinguishers. It is a class I ozone depleting substance with ozone depletion potential ODP = 0.74. It was banned by Montreal Protocol in 1996.

References

External links 

Halomethanes
Fire suppression agents
Refrigerants
Organobromides
Organofluorides
Ozone-depleting chemical substances
MCTS. MCTS may reference:

 Marine Communications and Traffic Services, a radio service operated by the Canadian Coast Guard which provides vessel traffic and marine weather information
 Microsoft Certified Technology Specialist, a professional certification from Microsoft
 Middelburg Center for Transatlantic Studies
 Milwaukee County Transit System 
 Monte Carlo tree search – a heuristic search algorithm based on the Monte Carlo method
 Multiple Console Time Sharing System, a 1970s operating system developed by General Motors Research Laboratory
 Munich Center for Technology in Society, a research center at the Technical University of Munich
 Mercer County Technical Schools, a vocational public school district in Mercer County, New Jersey, United States

See also
 MCT (disambiguation); MCTs plural form of MCT
List of HVDC projects. Electric power transmission through interconnectors using high-voltage direct-current (HVDC) involves usually two converter stations and a transmission line. Generally overhead lines are used, but an important class of HVDC projects use submarine power cables. A back-to-back station has no transmission line and joins two separate AC grids at a single point. Historical HVDC systems used the Thury system of motor-generators but these have all been made obsolete by later developments such as mercury-arc valves (now also obsolete), thyristors, and IGBT power transistors.

Legend
Converter technology:
 Thury = Series-connected generators as designed by René Thury
 Merc = Mercury-arc valve rectifier and inverter
 Thyr = Thyristor rectifier and inverter
 IGBT = Insulated gate bipolar transistor

Line status:

Africa

Australia and Oceania

Asia

Europe

2 As of 9 December 2015, LitPol Link started trial operations.
3 Caithness Moray HVDC serves a number of renewable energy sources in the north of Scotland  - see map 
4 Contracts due to be placed in 2016. 
5 Elia says construction expected to start in late 2017. 
6 Date is that quoted to support the Shetland Wind Farm that SSE is a part investor in.
7 Decision on project expected in 2017 following consultation - see SSE PD reference.

North America

South America

Back to back

Maps

Africa

Australia and Oceania

Europe

South America

See also

 Asian Super Grid
 Desertec
 Electrode line
 European super grid
 High-voltage direct current
 List of high voltage underground and submarine cables
 Lyon-Moutiers DC transmission scheme
 Scotland-Norway interconnector
 HVDC converter station
 Super grid
 Submarine power cable
 Transmission tower
 Uno Lamm
 Valve hall

References

Sources

 
HVDC
HVDC projects
Electric fireplace. An electric fireplace is an electric heater that mimics a fireplace burning coal, wood, or natural gas. Electric fireplaces are often placed in conventional fireplaces, which can then no longer be used for conventional fires. They plug into the wall, and can run on a "flame only" setting, or can be used as a heater, typically consuming 1.4 to 1.6 kW to heat a 40 m2 room.

History

The electric fire was invented in 1912 and became popular in the 1950s. Electric fireplaces found in 1950s homes were typically small and could be easily moved.

Techniques for electrical "flame effects" have been around since at least 1981.

Commercial electric fireplace techniques include the Optiflame, introduced in 1988 by Dimplex.

Dimplex claims to have produced the first electric fireplace with a "realistic" wood-burning flame effect in 1995.  It is unclear what specific technique is being referred to, although it may be .

In 2008 Dimplex launched the Opti-myst effect which simulates both flames and smoke.

In 2013 Dimplex launched the Opti-V effect which combines realistic flickering flames with three dimensional LED logs that sporadically sparks and an audio element of crackling logs.

Technology

Heating techniques 
Many electric fireplaces have heating coils that produce heat as electricity flows through it. The heated air is propelled out into open space by a fan. Other heating techniques used in electric fireplaces include PTC ceramic heating and infrared technology.

Controls 
Electric fireplaces are typically controlled by a remote or a set of buttons in which the temperature, lighting, and flame effects can be controlled. Some electric fireplaces are connected to an app in which the controls can be changed from the user's cell phone.

Advantages compared to traditional fireplaces
Advantages of electric fireplaces are that they:
 do not require chimneys.
 are often portable.
 do not require remodeling to install.
 are more economical.
 are more convenient.
 are safer to use (no risk of catching fire, inhaling smoke or gas, or overheating).
 can be installed without professional assistance.
 are better for the environment than wood burning and gas fireplaces.
 do not require the maintenance needed for wood burning or gas fireplaces.

Disadvantages compared to traditional fireplaces
Disadvantages of electric fireplaces are that they:
 can be more expensive to operate in rural areas compared to gas or wood burning heaters due to price of electricity.
 are sometimes not as realistic as real flames, even those in gas fireplaces. Additionally, they can lack other sensual cues of a real fire like the smell of burning wood, or crackle of a burning log.

See also 

 Firebox
 Fireplace insert
 Fireplace mantel
 Wood-fired oven

References

Fireplaces
Residential heating appliances
Spacestation Pheta. Spacestation Pheta is a video game for the Macintosh developed by T&T Software which was originally released as shareware in the late 1980s. It is a fast, multi-screen platform game, with each level (referred to as a "screen") containing features and obstacles such as transporters, ladders, cannons, trampolines, and so-called "materializers". The object of the game is to reach the end of each screen before running out of oxygen. 

The registered version of Spacestation Pheta contains a hundred built-in screens, plus an editor for creating custom screens. There is also a "show me the solution" feature for those who get stuck. Other features include printable help, digitized sound effects, and optional color graphics. 

Spacestation Pheta can be played on almost any 68k or PowerPC Macintosh computer, including compact black-and-white models such as the Macintosh Plus.

Sound effects in Spacestation Pheta were sampled by the electronic group Underworld.

A port of Spacestation Pheta was released on disk for the TI-99/4A home computer, written in Wycove Forth.

References

External links
 Spacestation Pheta at T&T Software

Classic Mac OS-only games
Classic Mac OS games
Platformers
Video games developed in the United States
Stencil jumping. Stencil jumping, at times called stencil walking, is an algorithm to locate the grid element enclosing a given point for any structured mesh. In simple words, given a point and a structured mesh, this algorithm will help locate the grid element that will enclose the given point.

This algorithm finds extensive use in Computational Fluid Dynamics (CFD) in terms of holecutting and interpolation when two meshes lie one inside the other. The other variations of the problem would be something like this: Given a place, at which latitude and longitude does it lie? The brute force algorithm would find the distance of the point from every mesh point and see which is smallest. Another approach would be to use a binary search algorithm which would yield a result comparable in speed to the stencil jumping algorithm. A combination of both the binary search and the stencil jumping algorithm will yield an optimum result in the minimum possible time.

The principle

Consider one grid element of a 2-dimensional mesh as shown, for simplicity and consider a point O inside.
The vertices of the grid element are denoted by A, B, C and D and the vectors AB, BC, CD, DA, OA, OB, OC and OD are represented.
The cross product of OA and AB will yield a vector perpendicular to the plane coming out of the screen. We say that the magnitude of the cross product is positive. It will be observed that the cross products of OB and BC, OC and CD; and OD and DA are all positive.

This is not the case when the point is outside.
Here we see that not all the cross products are positive. This is the major testing criterion in the algorithm.

How does it move forward?
The algorithm needs a guess grid element to start off. The grid element can be found by the location of one point say A. The other points can be automatically located by getting the subsequent points. The required cross products are then found in the order
 OA × AB
 OB × BC
 OC × CD
 OD × DA

Each of these cross products are checked one by one (in the order shown) on which becomes negative first. If OA × AB becomes negative first, the next guess should be one step ahead along DA. If OB × BC is negative first, move along AB by one step to find the next guess and so on.

The algorithm will converge at the exact grid element where all the cross products are positive.

See also
 Five-point stencil

References

External links
pegasus software

Geometric algorithms
Avro 560. The Avro 560  was a British single-engined ultralight monoplane built by Avro at Hamble Aerodrome.

Design and development
The Avro 560 was designed for the 1923 light aircraft trials for single-seaters at Lympne Aerodrome. The Avro 560 was an ultralight built of wood-and-fabric construction, a cantilever high-wing monoplane. It was powered by a  Blackburne Tomtit engine. The aircraft was flown by Bert Hinkler during the trials held in October 1923; the 560 did well and recorded an average of 63.3 mi (101.9 km) per Imp gal (4.5 L). The aircraft was evaluated by the Air Ministry after the trials but was not chosen for further production and only one 560 was built.

Operators

Air Ministry

Specifications

See also

References

External links

Avro 560 – British Aircraft Directory

1920s British civil utility aircraft
560
High-wing aircraft
Single-engined tractor aircraft
Aircraft first flown in 1923
Avro Club Cadet. The Avro Club Cadet was a 1930s single-engined British biplane trainer aircraft, designed and built by Avro as a development of the earlier Cadet. It was planned for private and club use and, unlike the Cadet, was fitted with folding wings.

Design and development
The Avro 638 Club Cadet was a modified version of the Avro Cadet, similarly intended for both private and club use. The Club Cadet was fitted with unstaggered wings, that could be folded to help save hangar space; the staggered biplane wings of the earlier Cadet were unsuitable to be adapted for folding. The prototype flew in May 1933, powered by an Armstrong Siddeley Genet Major radial piston engine, another 16 were built, and production finished in 1935.

A single prototype of an enclosed three-seat cabin version, the Avro 639 Cabin Cadet was built, and first flew in 1933, but did not enter production. A second three-seat version, the Avro 640 Cadet, was produced for joy-riding work, with a widened fuselage accommodating an open cockpit for two passengers side by side in front of the pilot. Nine of these were built, the first four powered by 140 hp (104 kW) Cirrus Hermes IV engines, and the remaining five powered by Genet Major engines.

Operational history
Most Club Cadets were used by flying schools, although intended for private as well as club use, the largest user being Airwork, that operated five Club Cadets. These were later re-engined with 130 hp (100 kW) de Havilland Gipsy Major engines; the air-cooled in-line inverted engines reduced drag, and gave improved fuel consumption.

Variants
Avro 638 Club Cadet
Two-seat trainer aircraft, powered by 135 hp (101 kW) Genet Major (radial) or 130 hp (100 kW) Gipsy Major I (inverted in-line) engine, 17 built.
Avro 638 Club Cadet Special
One aircraft, fitted with a 140 hp (104 kW) Cirrus Hermes IVA inverted in-line engine.
Avro 639 Cabin Cadet
Enclosed cockpit, one built.
Avro 640 Cadet
Three seat joyriding aircraft, powered by 140 hp (104 kW) Cirrus Hermes IV inverted in-line (first four aircraft) or 135 hp (101 kW) Genet Major engine, nine built.

Operators

Airwork

Specifications (Avro 638 Genet Major I)

See also

References

External links

Canadian Aviation Museum
Avro Club Cadet – British Aircraft of World War II

638
Biplanes
1930s British civil trainer aircraft
Single-engined tractor aircraft
Aircraft first flown in 1933
Aircraft with fixed conventional landing gear
Siemens DCO. The Siemens DCO (digital central office) electronic telephone switch was introduced in 1977 by Stromberg-Carlson, having been conceived by its new president, Leonard A. Muller, an ex IBM senior executive who infused Stromberg with his new digital awareness learned in IBM. In a revolutionary project headed by lead engineer and chief of project development, Mick Richmond, the Stromberg-Carlson DCO was one of the first digital class 5 telephone switches ever installed in the World's telecommunications network, Muller was quick to recognize the value digital technology brought to the science of electronic switching and commenced a major digital development program shortly after taking over management of Stromberg in 1974.  Stromberg-Carlson put their switch into service in July 1977 in a telephone exchange in Richmond Hill, Georgia.

The DCO came as DCO-SE (Digital Central Office - Small Exchange) for line side Central Office operation and the DCO-CS (DCO-Carrier Switch) for Long Distance carrier services. A few DCO's were created for the cellular phone networks, but this was very limited.

In 1990 Siemens purchased Stromberg Carlson and moved its EWSD production to the Lake Mary, Florida production facility in 1991. In the next few years Siemens slowly phased out the DCO as a line side central office switch.  The DCO-CS was continued through the 1990s to support regional LD companies. The DCO-CS was small on port capacity (just under 10,000), but was robust on features, more than most other carrier switches.

As the 1990s came to a close, many regional long distance companies were being bought up, or going out of business as their profitability had diminished. This also brought an end to DCO production as Siemens-Stromberg Carlson focused on marketing the EWSD.

In 2006 the entire Siemens DCO line was sold to Genband, originally a VoIP gateway / softswitch company from Texas, USA.

References

External links
 Siemens DCO Homepage

Telephone exchange equipment
Siemens products
Aviatik B.II (Germany). Note: Not to be confused with the Austro-Hungarian Aviatik B.II series 32, 32.7 and 34 which were different aircraft.

The Aviatik B.II was a reconnaissance aircraft built in Germany during World War I.

Design and development
The (German) Aviatik B.II was a two-seat biplane of conventional configuration that seated its pilot and observer in tandem, open cockpits. Compared to its predecessor, the B.I, the B.II had a more powerful engine and revised nose design that faired the powerplant in more neatly, and a single "rhino horn" collector stack for the exhaust. A variety of two- and three-bay wing designs were utilised during production. While originally no armament was fitted (in common with other B- class aircraft), later production versions received a machine gun for the observer. All were withdrawn from front line service by early 1916, however the type continued in use as a trainer for a time with advanced flying training units (it is known that the B.II served in this role at FEA 9 at Darmstadt during 1916).

Operators

Luftstreitkräfte

Specifications

References

Bibliography

External links

 luftfahrt-archiv.de
 Military Aircraft Database

1910s German military reconnaissance aircraft
B.II
Single-engined tractor aircraft
Biplanes
Aircraft first flown in 1915
Aircraft with fixed conventional landing gear
Aviatik. Automobil und Aviatik AG was a German aircraft manufacturer during World War I. The company was established at Mülhausen (today in France) in 1909 and soon became one of the country's leading producers of aircraft.  It relocated to Freiburg in 1914 and to Leipzig in 1916 and established a subsidiary in Vienna as Österreichisch-Ungarische Flugzeugfabrik Aviatik. During the war, the company became best known for its reconnaissance aircraft, the B.I and B.II, although the Austro-Hungarian subsidiary also produced a number of its own designs, including fighters such as the D.I.

History
The company was founded in December 1909 by the Alsatian Georges Chatel. It started with the license-production of French aircraft; Hanriot monoplanes and Farman biplanes. From 1912, the factory started building its own successful biplanes, designed by Robert Wild.

Just at the beginning of World War One, on 1 August 1914 the company was relocated to Freiburg due to French threat, and then to new facilities in Leipzig-Heiterblick in 1916. The company did not continue after the 1919 Treaty of Versailles.

Aircraft

Aviatik B.I
Aviatik B.II
Aviatik B.III
Aviatik C.I
Aviatik C.II
Aviatik C.III
Aviatik C.V
Aviatik (Ö) C.I
Aviatik (Berg) D.I
Aviatik (Berg) D.II
Aviatik D.III
Aviatik D.VII

See also
List of aircraft manufacturers

References

Bibliography
 
 

Defunct aircraft manufacturers of Germany
Manufacturing companies established in 1909
1909 establishments in Germany
1919 disestablishments in Germany
Manufacturing companies disestablished in 1919
BAT Bantam. The BAT F.K.23 Bantam was a British single-seat fighter biplane produced by British Aerial Transport Company Limited of London during World War I.

Design and development
Frederick Koolhoven's first design for the British Aerial Transport Company (BAT) was the F.K.22 single-seat fighter.  It was a two-bay biplane of wooden construction.  It was planned to have a 120 hp (90 kW) A.B.C Mosquito radial engine but the failure of this engine led to the installation of the 170 hp (127 kW) A.B.C.Wasp I in the first and third aircraft.  The second machine was fitted with a 100 hp (75 kW) Gnome Monosoupape rotary engine and was the first to fly at Martlesham Heath in January 1918.  The original contract called for six development aircraft but three aircraft were built as the F.K.23 Bantam I, the second prototype then being renamed the Bantam II.  The Bantam I was the same wooden structure but was slightly smaller.  Two further prototypes of the larger design were also built followed by at least 9 development aircraft.  One aircraft was delivered to the Royal Aircraft Establishment on 26 July 1918, one was delivered to the French at Villacoublay and a further aircraft to the United States Army Air Corps at Wright Field in 1922.

The production Bantam had to be modified due to unsatisfactory spin characteristics of the prototypes.  Continuous engine problems and downsizing of the Royal Air Force were factors in no more orders for the Bantam.  Koolhoven returned to Netherlands with one aircraft where it was re-engined with a 200 hp (149 kW) Armstrong Siddeley Lynx radial engine.  Several examples were operated as civil racing aircraft.

Variants
F.K.22 Bantam I 
Prototypes and evaluation version, 2 built.
F.K.23 Bantam II
Production aircraft, 3 prototypes + 9 aircraft were built.

Operators

French Air Force received 1 aircraft for evaluation.

Koolhoven factory operated 1 aircraft.

Royal Air Force operated 1 aircraft.

United States Army Air Corps received 1 aircraft for evaluation.

Survivors

One aircraft, registered K-123, originally on display at the Aviodome, Netherlands. The airplane was acquired by the Rijksmuseum in Amsterdam.
The remains of a second FK 23 are used to build a flying example. It is a project from the "vroege vogels" from Lelystad in the Netherlands.

Specifications (F.K.23 Bantam)

Notes

References

External links

BAT FK23 Bantam Walkaround photos at IdFlieg.com
 Contemporary technical description of F.K.23 Bantam with photographs and drawings.

1910s British fighter aircraft
Bantam
Biplanes
Single-engined tractor aircraft
Koolhoven aircraft
Aircraft first flown in 1918
Aviatik B.III. The Aviatik B.III was a reconnaissance aircraft built in Austria-Hungary during World War I. Aviatik's Austro-Hungarian subsidiary had built the German-designed B.II, and now further developed this design by adding a more powerful engine and armament in the form of a defensive machine gun and bomb racks. It was otherwise similar to Austro-Hungarian built B.IIs, incorporating the revisions that had been made locally to the original design. All were obsolete and out of service by the end of 1916.

Operators

Austro-Hungarian Imperial and Royal Aviation Troops

Specifications

References
 

B.III
1910s Austro-Hungarian military reconnaissance aircraft
Aircraft first flown in 1916
Aircraft with fixed conventional landing gear
Biplanes
Concatenation (disambiguation). Concatenation is a computer programming operation that joins strings together.

Concatenation may also refer to:
 Concatenation (architecture), an architectural composition
 Concatenation of paths, a construction in topology
 
 Concatenated SMS, a way of combining multiple SMS text messages sent to cellular phones
 Packet concatenation, a computer networking optimization that coalesces multiple packets under a single header
 cat (Unix), a Unix command to write the contents of one or more files to the standard output
 "Concatenation", the opening track of Swedish extreme metal band Meshuggah's album Chaosphere
 A technical term in Christian liturgy to refer to combining services which are normally performed at different times of the day

See also
 Catenation, the chemical bonding of atoms of the same element into a chain