omniomni/omni-engineering huggingface dataset:
Fuzzy associative matrix. A fuzzy associative matrix expresses fuzzy logic rules in tabular form. These rules usually take two variables as input, mapping cleanly to a two-dimensional matrix, although theoretically a matrix of any number of dimensions is possible. From the perspective of neuro-fuzzy systems, the mathematical matrix is called a "Fuzzy associative memory" because it stores the weights of the perceptron.

Applications
In the context of game AI programming, a fuzzy associative matrix helps to develop the rules for non-player characters. Suppose a professional is tasked with writing fuzzy logic rules for a video game monster. In the game being built, entities have two variables: hit points (HP) and firepower (FP):

This translates to:

 IF MonsterHP IS VeryLowHP AND MonsterFP IS VeryWeakFP THEN Retreat
 IF MonsterHP IS LowHP AND MonsterFP IS VeryWeakFP THEN Retreat
 IF MonsterHP IS MediumHP AND MonsterFP is VeryWeakFP THEN Defend

Multiple rules can fire at once, and often will, because the distinction between "very low" and "low" is fuzzy. If it is more "very low" than it is low, then the "very low" rule will generate a stronger response. The program will evaluate all the rules that fire and use an appropriate defuzzification method to generate its actual response.

An implementation of this system might use either the matrix or the explicit IF/THEN form. The matrix makes it easy to visualize the system, but it also makes it impossible to add a third variable just for one rule, so it is less flexible.

Identify a rule set
There is no inherent pattern in the matrix. It appears as if the rules were just made up, and indeed they were. This is both a strength and a weakness of fuzzy logic in general. It is often impractical or impossible to find an exact set of rules or formulae for dealing with a specific situation. For a sufficiently complex game, a mathematician would not be able to study the system and figure out a mathematically accurate set of rules. However, this weakness is intrinsic to the realities of the situation, not of fuzzy logic itself. The strength of the system is that even if one of the rules is wrong, even greatly wrong, other rules that are correct are likely to fire as well and they may compensate for the error.

This does not mean a fuzzy system should be sloppy. Depending on the system, it might get away with being sloppy, but it will underperform. While the rules are fairly arbitrary, they should be chosen carefully. If possible, an expert should decide on the rules, and the sets and rules should be tested vigorously and refined as needed. In this way, a fuzzy system is like an expert system. (Fuzzy logic is used in many true expert systems, as well.)

References

Fuzzy logic
Matrices
Advanced Soaring Concepts Falcon. The Advanced Soaring Concepts Falcon, also called the Advanced Soaring Concepts American Falcon, is an American mid-wing, T-tailed, single-seat, FAI 15-Metre Class glider that was designed by Tor Jensen and produced by Advanced Soaring Concepts, and first flew in 1993. The aircraft was produced as a kit for amateur construction.

Design and development
The Falcon was designed by Jensen as the 15-metre class version of the FAI Standard Class Spirit.

The aircraft is made predominantly from fiberglass sandwiches, with the wing spar made from carbon-fiber-reinforced polymer. The cockpit is made from welded steel tube, reinforced with Aramid. Its  span wing has optional extensions that bring the span to . Glidepath control is via full span trailing edge flaps, coupled with top surface Schempp-Hirth-style airbrakes. The flaps can be set to +15°, +10°, +5°, 0°, and -5° in flight. The cockpit was designed to accommodate a pilot of up to  in height and weighing up to  with parachute. The landing gear is a retractable monowheel.

Specifications (Falcon)

See also

References

1990s United States sailplanes
Homebuilt aircraft
Aircraft first flown in 1993
T-tail aircraft
Advanced Soaring Concepts Spirit. The Advanced Soaring Concepts Spirit, also called the Advanced Soaring Concepts American Spirit, is an American mid-wing, T-tailed. single-seat, FAI Standard Class glider that was designed by Tor Jensen and produced by Advanced Soaring Concepts, first flying in 1992. The aircraft was produced in kit form for amateur construction.

Design and development
The Spirit was the Standard Class design that paralleled the company's FAI 15-Metre Class Falcon.

The aircraft is made from a welded steel tubing, with an Aramid reinforced cockpit section. Its  span wing employs a Carbon-fiber-reinforced polymer spar and carbon sandwich construction. The kit came with pre-molded fiberglass parts. The cockpit was designed to accommodate a pilot of up to  in height and weighing up to  with parachute.

Specifications (Spirit)

See also

References

Glider aircraft
Homebuilt aircraft
1990s United States sailplanes
Aircraft first flown in 1992
Advanced Soaring Concepts Apex. 

The Advanced Soaring Concepts Apex was a remotely piloted sailplane designed to take part in a NASA study of high-altitude aerodynamics.

It was planned to lift the aircraft to around 100,000 ft (30,487 m) by balloon and release it there.

Rockets would assist the aircraft to transition to horizontal flight. The Apex's wing was designed by Dr Mark Drela of the Massachusetts Institute of Technology, and mounted a "wake rake" containing sensors to measure drag behind the wing.

Flights were originally scheduled for 1998, but the program fell behind schedule.

In January 1999, the aircraft was reportedly under construction and would be delivered to the Dryden Flight Research Center for flights beginning in March or early April. By that time, however, the project had been mothballed.

It was revived briefly one year later, before being cancelled altogether.

References
 Description of Apex project on NASA Dryden website
 
 NASA Dryden news release 6 April 1998 - NASA's environmental research aircraft and sensor technology program Apex project completes critical design review

Apex
1990s United States experimental aircraft
1990s United States sailplanes
Unmanned aerial vehicles of the United States
Glider aircraft
Mid-wing aircraft
AEA Red Wing. The Red Wing (or Aerodrome #1) was an early aircraft designed by Thomas Selfridge and built by the Aerial Experiment Association in 1908. It was named for the bright red color of its silk wings — chosen to achieve the best result with the photographic materials and techniques of the day.

On 12 March 1908 Frederick W. Baldwin piloted the aircraft off the frozen Keuka Lake near Hammondsport, New York in what would be the first public demonstration of a powered aircraft flight in the United States as well as the first flight by a Canadian pilot.

Contemporary accounts described the flight as the "First Public Trip of Heavier-than-air Car in America."  Reports entitled "Views of an Expert" stated that Professor Alexander Graham Bell's new machine, the Red Wing, built from plans by Lieutenant Selfridge, was "shown to be practicable by flight over Keuka Lake, Hammondsport, New York, 12 March 1908 by F. W. Baldwin, the engineer in charge of its construction."

The aircraft covered 319 ft (97 m) at a height of around 20 ft (6 m). This was said to be the longest "first flight" by either an aircraft or a pilot, up to that date.  On March 17 Baldwin attempted a second flight, also from the ice of Keuka Lake, before crashing 20 seconds after takeoff. A portion of the tail gave way, bringing the test to an end. The Red Wing was damaged beyond repair.

Specifications (Red Wing)

References
Notes

Bibliography

Aerofiles. Retrieved: 19 May 2005.
"The Red Wing - Aerodrome 1". Retrieved: 18 April 2016.

See also

Red Wing
1900s Canadian experimental aircraft
1900s United States experimental aircraft
Alexander Graham Bell
Aircraft first flown in 1908
Single-engined piston aircraft
ATOS. or  is a computerized control system used by the East Japan Railway Company to regulate train traffic on railway lines in metropolitan Tokyo, Japan. It was designed by Hitachi. The first deployment was on the Chūō Main Line in 1997. It is now used on fourteen lines listed below.

On ATOS-enabled lines, each train station has electronic displays, which show scheduled arrival times and train destinations in Japanese and English, warn passengers when trains are arriving or passing through, send updates on system delays and accidents, and display messages to advertise JR products or warn passengers not to smoke. Pre-recorded voice announcements in train stations are also automated by ATOS.

ATOS also directs train drivers through 16-by-16 lamp matrices, which flash messages telling the train driver to speed up, slow down, or adjust their scheduled departure time in order to keep the entire network running on schedule.

Several JR lines in the Kantō region use CTC or PRC systems in lieu of ATOS.

ATOS-enabled lines
 Chūō Main Line in metro Tokyo (March 1997)
 Yamanote Line (August 1998)
 Keihin-Tohoku Line (August 1998)
 Sobu Line (Rapid and Local) west of  (June 1999)
 Yokosuka Line north of  (July 2000)
 Tōkaidō Main Line (Passenger and freight) (September 2001)
 Joban Line (Rapid and Local) (January 2004)
 Tohoku Main Line (December 2004)
 Takasaki Line (December 2004)
 Saikyo Line (July 2005)
 Kawagoe Line (July 2005)
 Yamanote Freight Line (July 2005)
 Nambu Line (March 2006)
 Tohoku Freight Line (December 2004)
 Yokosuka Line (Ofuna - Kurihama) (November 2009)
 Musashino Line (January 2012)
 Yokohama Line (July 2015)
 Keiyō Line (September 2016)

Future ATOS-enabled lines
 Ōme Line ( - )
 Itsukaichi Line

Further reading
 JR East Technical Review has several articles about digital train control and ATOS.

See also
Autonomous decentralized system

Rail transport in Tokyo
Rail transport operations
AEA White Wing. The White Wing (or Aerodrome #2) was an early US aircraft designed by Frederick W. Baldwin and built by the Aerial Experiment Association in 1908. Unusual for aircraft of its day, it featured a wheeled undercarriage. The wings were equipped with ailerons controlled by a harness worn around the pilot's body; leaning in one direction would cause the aircraft to bank to follow.  The ailerons led to a legal dispute with the Wright brothers over the brothers' patent on movable wing surfaces.

First piloted by Baldwin himself on 18 May and the aircraft flew very well. White Wing was then piloted by Lt Thomas Selfridge at Hammondsport, New York, on 19 May 1908 (becoming the first US Army officer to fly an airplane) and then Glenn Curtiss made a flight of 1,017 ft (310 m) in it on 21 May. On 23 May, it crashed during a landing by John McCurdy and was damaged beyond repair.

Specifications (White Wing)

See also

References

Notes

Bibliography

External links

 Aerofiles

Biplanes
1900s Canadian experimental aircraft
1900s United States experimental aircraft
White WIng
Alexander Graham Bell
Aircraft first flown in 1908
Single-engined piston aircraft
AEA Cygnet. The Cygnet (or Aerodrome #5) was an extremely unorthodox early Canadian aircraft, with a wall-like "wing" made up of 3,393 tetrahedral cells. It was a powered version of the Cygnet tetrahedral kite designed by Dr Alexander Graham Bell in 1907 and built by the newly founded Aerial Experiment Association.

Design and development
Bell's experiments with tetrahedral kites had explored the advantages of utilizing great banks of cells to create a lifting body leading to the Cygnet I. On 6 December 1907, Thomas Selfridge piloted the kite as it was towed into the air behind a motorboat, eventually reaching a height of 168 ft (51 m). This was the first recorded heavier-than-air flight in Canada. While demonstrably able to fly as a person-carrying kite, it seemed unpromising as a direction for research into powered flight. It was difficult to control, and was in fact destroyed when it hit the water at the end of the flight.

The following year, a smaller copy of the design was built as the Cygnet II, now equipped with wheeled undercarriage and a Curtiss V-8 engine.

Operational history
Attempts to fly the Cygnet II at Baddeck, Nova Scotia between 22 and 24 February 1909, met with failure. When the AEA Silver Dart was ready for flight testing, the engine was removed from the Cygnet II, and then returned. Rebuilt again as the Cygnet III with a more powerful 70 hp Gnome Gamma engine, its final flight was on 19 March 1912, at Bras d'Or Lake, Nova Scotia, piloted by John McCurdy. The results were highly unsatisfactory with the Cygnet III only able to lift off the ground for a foot or two, typically considered remaining in ground effect. After a final trial on 17 March, the tetrahedral cell bank failed structurally, leaving the aircraft irreparably damaged. The Cygnet II and III were abandoned following this flight attempt.

Specifications (Cygnet III)

See also
 Man-lifting kite
 List of experimental aircraft

References
Notes

Bibliography

 "Aerial Experimental Association (A E A)." Aerofiles,  1 June 2005.
 Angelucci, Enzo. World Aircraft: Origins to World War 1. Chicago: Rand McNally & Co, 1975. .
 Dailey, John R. Smithsonian National Air and Space Museum: An Autobiography. Washington, D.C.: National Geographic, 2010. . 
 Milberry, Larry. Aviation in Canada: The Pioneer Decades, Vol. 1. Toronto: CANAV Books, 2008. .
 Molson, Ken M. and Harold A. Taylor. Canadian Aircraft Since 1909. Stittsville, Ontario: Canada's Wings, Inc., 1982. .
 Payne, Stephen, ed. Canadian Wings: A Remarkable Century of Flight. Vancouver: Douglas & McIntyre, 2006. .

Cygnet
1900s Canadian experimental aircraft
1900s United States experimental aircraft
Victoria County, Nova Scotia
Alexander Graham Bell
Multiplane aircraft
Aircraft first flown in 1907
Single-engined piston aircraft
SBR. SBR may refer to:

Science and technology
 Sequencing batch reactor, for wastewater treatment
 Spectral band replication, to enhance audio codecs
 Shooting and bouncing rays, in computational electromagnetics 
 Styrene-butadiene rubbers
 Serum bilirubin, in blood
 Screen-to-body ratio, a measurement for smartphones and tablets

Military
 Short-barreled rifle, US legal designation
 Space-based radar, on satellites

Organizations
 SBR Creative Media, advising radio stations
 Specialised Bulk Rail, a subsidiary of SCT Logistics in Australia
 Sportsbook Review, American sportsbook review website
 Station biologique de Roscoff, French oceanography station
 Stratford on Avon and Broadway Railway, England
 Stone Brothers Racing, a former Australian motor racing team

Other uses
 Skills-based routing, of phone calls
 Standard Business Reporting, programs to reduce business regulations
 Shanghai Business Review
 Samuel Butler Room, the Middle Combination Room of St John's College, Cambridge
 Summit Bechtel Reserve, of the Boy Scouts of America
JoJo's Bizarre Adventure: Steel Ball Run, manga written by Hirohiko Araki
Saibai Island Airport, IATA airport code "SBR"
 Seat belt Reminder, an assessment topic of Latin NCAP
Internet Mail 2000. Internet Mail 2000 is an Internet mail architecture proposed by Daniel J. Bernstein (and in subsequent years separately proposed by several others), designed with the precept that the initial storage of mail messages be the responsibility of the sender, and not of the recipient as it is with the SMTP-based Internet mail architecture.

Whereas the SMTP-based Internet mail architecture has a close analogue in the architecture of paper mail, this is not the case for Internet Mail 2000.  Its architecture depends on various things that are unique to the natures of the Internet and to electronic messages.  One of its goals is to reduce spam.

Implementations 
Over the years since Daniel J. Bernstein proposed it, several attempts have been made to design and to implement a real Internet Mail 2000 system, with varying degrees of achievement.  The closest thing to a concrete, open implementation of the system is Meng Weng Wong's StubMail, which was presented at Google in July 2006.

See also 
Bernstein has also suggested the Quick Mail Transfer Protocol (QMTP).

External links 
 Daniel J. Bernstein's original IM2000 outline (2000)
 Brett Watson's proposal (2002)
 JFC Morfin's proposal (2003) describing weemail
  — Jonathan de Boyne Pollard's detailed proposed specifications and elaboration of the system
 Duan's, Dong's, and Gopalan's proposal (2004) and subsequent Internet Draft (2006) describing Differentiated Mail Transfer Protocol (DMTP)
 Nathan Cheng's proposal (2006) describing Hypertext Mail Protocol (HTMP)
 Andrew Walrond's HeresyMail  (seems to be abandoned?)
 Chrobok's, Trotman's, and O'Keefe's proposal which extends SMTP with Internet Mail 2000 features (General delivery)

Email
PFC. PFC may refer to:

Science and technology
 Perfluorinated compound, organofluorine compounds with hydrogen replaced by fluorine and other heteroatoms
 Perfluorocarbons, hydrocarbon derivatives containing only carbon and fluorine atoms
 Blood substitute, some of which are made of perfluorocarbons
 Plasma-facing components, in a fusion reactor
 Prefrontal cortex, the anterior part of the frontal lobes of the brain
 Phonologie du Français Contemporain, French phonology research project
 Physiological functional capacity, the ability to perform the physical tasks of daily life

Technology
 Parallel flange channel, a type of steel beam
 Power factor correction, of electric loads
 Power foundation classes, computer libraries for PowerBuilder
 Priority flow control, Ethernet technology

Organizations
 Power Finance Corporation, an Indian financial institution
 PFC Energy, a global energy research and consultancy group
 Pacific Fur Company, a former fur trading venture
 Playing for Change, a multimedia music project

Sports

Association football
 Paris FC, France
 Paulínia FC, São Paulo, Brazil
 Persepolis F.C., Tehran, Iran
 PFC Beroe Stara Zagora, Bulgaria
 Port F.C., Thailand
 Portsmouth F.C., England
 Pacific FC, Vancouver Island, Canada
 FK Partizan, Belgrade, Serbia

Other sports
 Pillow Fight Championship, US professional sports organization
 Palace Fighting Championship, former US martial arts organization
 Pure Fusion Collective, a women’s stable in professional wrestling organization WWE

Other uses
 Passenger facility charge, a tax on air travelers
 Pacific City State Airport (IATA airport code), near Pacific City, Oregon, US
 Price forward curve, a method to determine the forecasted price of a commodity
 Private first class, a junior military rank
Atlas XH-1 Alpha. The Atlas XH-1 Alpha is a prototype attack helicopter built by Atlas Aviation (now Denel) of South Africa, which used it as a concept demonstrator for the then-planned Rooivalk project.

Development
It was developed from an Aérospatiale Alouette III airframe, retaining that helicopter's engine and dynamic components, but replacing the original cockpit with a stepped tandem one, adding a 20 mm cannon under the chin and converting the undercarriage to tail-dragger configuration.

The XH-1 first flew on 3 February 1985, and soon embarked on a rigorous flight test program to examine the feasibility of a dedicated attack helicopter in southern African conditions. The results were ultimately good enough to convince Atlas and the South African Air Force to go ahead with the development of a dedicated attack helicopter, the Denel Rooivalk.

The XH-1 and Rooivalk are completely different aircraft and share no components. The Rooivalk was developed from the later XH-2 prototype.

The sole XH-1 was retired sometime in the late 1980s and was handed over to the South African Air Force Museum, where it remains to this day.

Specifications (XH-1)

See also

References

Military helicopters
1980s South African attack aircraft
1980s South African helicopters
XH-1
1980s South African experimental aircraft
Cold War military equipment of South Africa
Single-turbine helicopters
Aircraft first flown in 1985
Role-oriented programming. Role-oriented programming as a form of computer programming aims at expressing things in terms that are analogous to human conceptual understanding of the world. This should make programs easier to understand and maintain.

The main idea of role-oriented programming is that humans think in terms of roles. This claim is often backed up by examples of social relations. For example, a student attending a class and the same student at a party are the same person, yet that person plays two different roles. In particular, the interactions of this person with the outside world depend on his current role. The roles typically share features, e.g., the intrinsic properties of being a person. This sharing of properties is often handled by the delegation mechanism.

In the older literature and in the field of databases, it seems that there has been little consideration for the context in which roles interplay with each other. Such a context is being established in newer role- and aspect-oriented programming languages such as Object Teams. Compare the use of "role" as "a set of software programs (services) that enable a server to perform specific functions for users or computers on the network" in Windows Server jargon.

Many researchers have argued the advantages of roles in modeling and implementation. Roles allow objects to evolve over time, they enable independent and concurrently existing views (interfaces) of the object, explicating the different contexts of the object, and  separating concerns. Generally roles are a natural element of human daily concept-forming. Roles in programming languages enable objects to have changing interfaces, as we see in real life - things change over time, are used differently in different contexts, etc.

Authors of role literature
 Barbara Pernici
 Bent Bruun Kristensen
 Bruce Wallace
 Charles Bachman
 Friedrich Steimann
 Georg Gottlob
 Kasper B. Graversen
 Kasper Østerbye
 Stephan Herrmann
 Trygve Reenskaug
 Thomas Kühn

Programming languages with explicit support for roles
 Cameleon
 EpsilonJ
 JavaScript Delegation - Functions as Roles (Traits and Mixins)
 Object Teams
 Perl (Moose)
 Raku
 powerJava
 SCala ROLes Language

See also
 Aspect-oriented programming
 Data, context and interaction
 Object Oriented Role Analysis Method
 Object-role modeling
 Subject (programming)
 Subject-oriented programming
 Traits (computer science)

References

External links
 Adaptive Plug-and-Play Components for Evolutionary Software Development, by Mira Mezini and Karl Lieberherr
 Context Aspect Sensitive Services
 Overview and taxonomy of Role languages
 ROPE: Role Oriented Programming Environment for Multiagent Systems

Object-based programming languages
Programming paradigms
Aerfer. Aerfer was an Italian manufacturing company created in 1955 by the merger of IMAM and Officine Ferroviarie Meridionali. The name is a contraction of Costruzioni Aeronautiche e Ferroviarie (Aeronautical and Railway Constructions).

In 1969 it merged with Salmoiraghi and the aviation division of Fiat to create Aeritalia.

The firm is remembered mostly in connection with the development of Italy's first supersonic jet, the Aerfer Sagittario 2.

List of aircraft
SAI.7 (1939) Single propeller engine single-seat racing aircraft
SAI.7T (1943) Single propeller engine two-seat training aircraft
S.7 (1949) Single propeller engine two-seat touring aircraft
Supersette (1951) Single propeller engine two-seat trainer/racing aircraft
Sagittario (1953) Single jet engine adaptation of S.7 aircraft, with wooden wings and tail surfaces
Aerfer Sagittario 2 (1956) All-metal development of Sagittario.  Broke sound barrier.
Aerfer Ariete (1958) Development of Sagittario 2 with additional jet engine for climb and speed
Aerfer Leone (1959) Proposed development of Sagittario 2 with additional rocket engine for climb and speed.  Not built

See also

 List of Italian companies

References

 
Italian companies established in 1955
1969 disestablishments in Italy
Vehicle manufacturing companies established in 1955
Manufacturing companies disestablished in 1969
Defunct aircraft manufacturers of Italy
Aeritalia