omniomni/omni-engineering huggingface dataset:
External water spray system. An external water spray system (EWSS) is a domestic external fire sprinkler system designed to protect homes from bushfires and  wildfires. While external spray systems have long been used in fire protection for buildings and facilities, EWSS refers to domestic bushfire/wildfire systems.

Usage 
The types of systems vary greatly from a single impact sprinkler placed on a roof, systems installed during construction with sprays on all windows and doors, and small sprays damping gutters. Some are installed using copper piping and sprays while others use common PVC piping.

Usage depends on type of risk and belief of effectiveness. Copper piping is used to withstand high temperatures that may be experienced during a fire front or for higher reliability for in ceiling installations. External PVC piping is used where failure with exposure to high radiant heat is acceptable, as at the time the system is considered have "done its job". This is a matter of personal judgment.

Issues
There is a lack of scientific research regarding EWSS. Other issues that may affect the effectiveness of an EWSS:

 Sprinkler performance in high wind conditions typical in a bushfire
 Home design
 High vulnerability areas.  e.g. decking
 Garden beds near walls
 Window sills
 Large windows (heat radiation)
 Internal furnishings (e.g. curtains)
 Home location
 Slope
 Surrounding vegetation
 If defended by occupiers
 Preparation (if prepared for defense)
 If intended for remote (unattended) defense
 Available water supply
 Ember attack
 Fire front (radiant heat)
 Adjacent building or vegetation fire

Types
 Roof impact sprinkler
 Gutter sprays
 Window spray / deluge

Commercial sprays designed for EWSS are available, but most systems use commonly available irrigation sprinklers/sprays.

Research
External spray systems for buildings are well documented for protection from fires in adjacent buildings.  However, up there is little published scientific research on scientific information pertaining to the effectiveness of EWSS under varying wildfire conditions.

See also
 Active fire protection
 Passive fire protection
 Fire protection
 Fire protection engineering
 Architectural engineering

References

External links

National Fire Sprinkler Association
British Automatic Fire Sprinkler Association

Firefighting equipment
Safety equipment
Hydraulics
Plumbing
Piping
Fire suppression
Murray Joslin. William Murray Joslin (November 21, 1901 – July 1981) was an electrical engineer who made major contributions to nuclear power. He was born in Independence, Iowa.

Biography
Joslin obtained his Bachelor of Science degree in electrical engineering from Iowa State University in 1923.

He joined Commonwealth Edison Company, where he became a vice-president of Commonwealth Edison in 1953 and subsequently headed various activities of the company including the early development of nuclear power. The American Society of Mechanical Engineers elected him Fellow in 1973. He received the IEEE Edison Medal in 1976.

References
IEEE History Site

1901 births
1981 deaths
American electrical engineers
IEEE Edison Medal recipients
People from Independence, Iowa
20th-century American engineers
Iowa State University alumni
Engineering School of the University of Caen Normandy. The Engineering School of  the University of Caen Normandy (in French: ESIX Normandie, before EIC - École d'Ingénieurs de Cherbourg) is a French engineering university funded in 1993.

It is situated in Normandy in two cities: Caen and Cherbourg.

The school is accredited by the "Commission des titres d'ingénieur" to deliver Engineering Degrees.

Teaching 
The school has three departments:
 Food Sciences
 Industrial Systems Engineering (industrial production or nuclear operations) 
 Mecatronics

International relations 
The school has agreements allowing students to attend semester(s) in foreign countries:
In Austria:
Fachhochschule Vorarlberg University of Applied Sciences - Department of Mechatronics
In Sweden:
Linköping Institute of Technology - Department of Manufacturing Management
Royal Institute of Technology, KTH Stockholm - Department of Production Engineering
In Finland:
Tampere University of Technology

External links 
Official website

Engineering universities and colleges in France
Universities in Normandy
Educational institutions established in 1993
1993 establishments in France
CAP-1 Planalto. 

The CAP-1 Planalto was a military trainer aircraft built in Brazil during World War II. It was a low-wing cantilever monoplane with fixed tailwheel undercarriage that accommodated the pilot and instructor in tandem open cockpits. The project had been initiated by Instituto de Pesquisas Tecnológicas (IPT) under the designation IPT-4 and although the design work had been contracted to CAP, IPT insisted on a wing profile of its own choosing that led to serious stability problems in the final product.

The CAP-3 replaced the CAP-1's Franklin 4AC engine with a de Havilland Gipsy with double its power, but the stability problems remained unaddressed until CAP engineer Oswaldo Fadigas redesigned the wing in the CAP-6. The firm attempted to sell this latter type to the Ministry of Aeronautics, but succeeded only in selling conversion kits for the existing CAP-1s and -3s in the military's inventory.

Specifications

References

External links
 Aeroclube de Joinville website

Low-wing aircraft
Planalto
Single-engined tractor aircraft
1940s Brazilian military trainer aircraft
Aircraft first flown in 1942
Single-engined piston aircraft
Aircraft with fixed conventional landing gear
Class 01. Class 01 may refer to:

British Rail Class 01, a class of post-war British 0-4-0 diesel locomotive designed for use on tight curves and limited clearances
British Rail Class 01/5, encompasses a variety of privately owned shunting locomotives
DRG Class 01, a class of German standard steam locomotive designed between the wars for express train services
DRG Class 01.10, a later, more powerful version of the DRG Class 01 above first delivered in 1939
Class 01, in the electrical Appliance classes

See also
 Class 1 (disambiguation)
 Class I (disambiguation)
CAP-4 Paulistinha. The CAP-4 Paulistinha was a military and civilian trainer aircraft built in Brazil during the 1930s and 1940s.

Design and development
The CAP-4 was originally developed by Empresa Aeronáutica Ypiranga as an unlicensed copy of the Taylor Cub powered by a Salmson 9Ad radial engine.  It featured a high strut-braced wing, two enclosed tandem seats, and a steel-tube fuselage with fabric covering.  Its tailwheel undercarriage was not retractable.

EAY had built five examples by the time that the firm was purchased by Companhia Aeronáutica Paulista in 1942. CAP continued manufacturing the type under the designation CAP-4.

The type was widely successful, with nearly 800 units being produced for Brazil's flying clubs and armed forces, as well as for export to Argentina, Paraguay, Chile, Uruguay and Portugal.  At the time of peak production in 1943, a new CAP-4 left the factory every day, and production continued until 1948.

In 1956, Sociedade Aeronáutica Neiva acquired the rights renaming it to P-56 Paulistinha, the design was used as the basis for an agricultural aircraft, the P-56 Agricola, adding a fibreglass chemical hopper and spraybars, but this was unable to compete with imported, purpose-built agricultural aircraft.

Variants
EAY-201original radial engined version
CAP-4main production version
CAP-4Bair ambulance version (2 prototypes built)
CAP-4Cartillery-spotting version, (Paulistinha Rádio or Paulistinha Observação)
P-56 Agricolaagricultural version by Neiva (60 built)
Paulistinha 56-CPowered by  Continental C-90-8F/12F engine. 256 built by Neiva between 1958 and 1964.
P56C-1 Paulistinha Rebocador
Paulistinha 56-DMore powerful version with  Lycoming O-320-A1A. Single prototype built, which was designated L-6A by Brazilian Air Force. No production.

Former operators

Brazilian Navy

Paraguayan Military Aviation 4 aircraft bought in the early 1960s
Paraguayan Aeroclub 4 aircraft bought in the 1950s

Specifications (CAP-4)

References
Notes

Bibliography
  
 
 
 Aeroclube de Joinville website

External links

 Brazilian Naval Air Arm - CAP Paulistinha

Paulistinha
Single-engined tractor aircraft
High-wing aircraft
1930s Brazilian military trainer aircraft
1930s Brazilian civil trainer aircraft
Neiva aircraft
Aircraft first flown in 1935
Aircraft with fixed conventional landing gear
Single-engined piston aircraft
Pelikan tail. The Pelikan tail is an experimental tail design for fighter jets. It was originally conceived by Ralph Pelikan, who was hired by McDonnell Aircraft, later worked for McDonnell Douglas after the merger of McDonnell with Douglas and, after another merger, retired from Boeing. The concept was used in the Northrop YF-23 fighter. However, it has been considered or included in design specifications in the McDonnell Douglas  BAE Joint Strike fighter (JSF) design which was eliminated  before prototype stage

Advantages and disadvantages
The Pelikan design differs from the typical layout of flight control surfaces and empennage (incorporating ailerons on the wing, a horizontal stabilizer with elevators and a vertical stabilizer with a rudder), in that it uses only two moveable surfaces in order to achieve control of pitch, yaw and roll. When evaluated by Boeing engineers in October 1998 while designing what became the X-32, they found advantages of greater pitch control at high angles of attack and that two tail surfaces would have a lower radar signature than the four surfaces eventually adopted. However, they also found that using two larger control surfaces instead of four might actually make the aircraft heavier. The bigger hydraulic pumps and cylinders needed to operate the larger surfaces would add  of weight to the design. This and other factors made them use a four-surface tail instead.

Tests by Virginia Tech students
Virginia Tech students built a model aircraft with a Pelikan tail and got positive results for its viability using a wind tunnel. The analysis by the students found several advantages

See also
 Cruciform tail
 T-tail
 Twin tail
 V-tail

References

Virginia Tech
Aircraft tail configurations
CAP-5 Carioca. The CAP-5 Carioca was a civil trainer aircraft developed in Brazil during World War II.  It was essentially an enlarged version of the CAP-4, itself an unlicensed copy of the Taylor Cub. The CAP-5 had a bigger cabin, more powerful engine, and revised flying surfaces. Certification proved difficult to obtain, and eventually only seven aircraft were built, going to Brazilian aero clubs. The design was briefly revived in 1948 for what was to be CAP's last design, the CAP-9 air ambulance. Again, few were made.

See also

References
 
 Aeroclube de Joinville website

1940s Brazilian civil trainer aircraft
CAP-05
High-wing aircraft
Single-engined tractor aircraft
Aircraft first flown in 1945
Single-engined piston aircraft
Aircraft with fixed conventional landing gear
Companhia Aeronáutica Paulista. Companhia Aeronáutica Paulista usually known as CAP was a Brazilian aircraft manufacturer established in São Paulo.

History
It acquired the assets of Empresa Aeronáutica Ypiranga the same year it was founded and with them, the design that was to become its most important product, the CAP-4. Despite strong sales of this aircraft (nearly 800 were built), the company ran into financial problems in 1948 and was forced to close. The remaining assets were nationalized, with some eventually being taken over by Neiva.

Aircraft

References

Defunct aircraft manufacturers of Brazil
Manufacturing companies based in São Paulo
CFL Class 4000. The CFL class 4000 is a variant of the Bombardier TRAXX locos found working across Europe. Within Luxembourg they work on the local passenger services, crossing the borders into France or Belgium as necessary. They also work freight traffic. Their 15 kV capability allows them to work across the border to Germany. Even though they are capable of running in France, they are not allowed to do so for security reasons.

Their slab sided body work has been used for advertising.

External links
Rail.lu page
D'Serie 4000 op dem Site vum CFL
Spoorgroep Luxemburg

4000
25 kV AC locomotives
15 kV AC locomotives
Bo′Bo′ locomotives
Electric locomotives of Luxembourg
Railway locomotives introduced in 2004
TRAXX
Standard gauge locomotives of Luxembourg
Ivchenko AI-26. The Ivchenko AI-26 is a seven-cylinder air-cooled radial engine used in early Soviet helicopters and later used in light utility aircraft.

Design and development
The AI-26 engine was designed by A.G Ivchenko in 1945 with the early designation M-26, later the designation was changed to AI-26.  Like the Shvetsov ASh-21 which is basically one bank of cylinders from the Shvetsov ASh-82, the AI-26 was also influenced by the ASh-82.  The AI-26 retained the bore, stroke and displacement of the ASh-21 while incorporating new features peculiar to its role.  This similarity allowed the AI-26 to use the same production jigs as the ASh-21 and ASh-82 which reduced costs and simplified production.  

The engine was envisioned as a helicopter engine, but the early test models lacked the necessary equipment to facilitate this role, such as an auxiliary cooling fan, reduction gears and clutch.  The GR suffix means "Gelikopter", or helicopter. Engine testing was completed by early 1946 and by 1947 helicopter testing had begun.  In late 1947 the decision to mass-produce the engine was made and production commenced at factory No.478 located in Zaporizhia.  Between 1947 and the 1970s some 1,300 AI-26GR's were produced.  The AI-26V model was also produced in Poland during the 1960s as the LiT-3 and later as the PZL-3S.

Applications
 Air Tractor AT-401A
 Ayres Thrush
 Mil Mi-1
 PZL-106 Kruk

Specifications (Ivchenko AI-26GR)

See also
 List of aircraft engines

References

 

1940s aircraft piston engines
Aircraft air-cooled radial piston engines
Ivchenko-Progress aircraft engines
Dirty bit. A dirty bit or modified bit is a bit that is associated with a block of computer memory and indicates whether the corresponding block of memory has been modified. The dirty bit is set when the processor writes to (modifies) this memory. The bit indicates that its associated block of memory has been modified and has not been saved to  storage  yet. When a block of memory is to be replaced, its corresponding dirty bit is checked to see if the block needs to be written back to secondary memory before being replaced or if it can simply be removed. Dirty bits are used by the CPU cache and in the page replacement algorithms of an operating system.

Dirty bits can also be used in Incremental computing by marking segments of data that need to be processed or have yet to be processed. This technique can be used with delayed computing to avoid unnecessary processing of objects or states that have not changed. When the model is updated (usually by multiple sources), only the segments that need to be reprocessed will be marked dirty. Afterwards, an algorithm will scan the model for dirty segments and process them, marking them as clean. This ensures the unchanged segments are not recalculated and saves processor time.

Page replacement 
When speaking about page replacement, each page may have a modify bit associated with it in the hardware.  The dirty bit for a page is set by the hardware whenever any word or byte in the page is written into, indicating that the page has been modified.  When a page is selected for replacement, the modify bit is examined.  If the bit is set, the page has been modified since it was read in from the disk.  In this case, the page must be written to the disk.  If the dirty bit is not set, however, the page has not been modified since it was read into memory.  Therefore, if the copy of the page on the disk has not been overwritten (by some other page, for example), then there is no need to write the memory page to the disk: it is already there.

References 

Central processing unit
Operating system technology
Samuel H. Caldwell. Samuel Hawks Caldwell (January 15, 1904 – October 12, 1960) was an American electrical engineer, known for his contributions to the early computers.

Early life and education
Caldwell enrolled at MIT in 1921, where he completed his bachelor's, master's and doctoral degrees in electrical engineering.  His M.Sc. thesis was entitled Electrical characteristics and theory of operation of a dry electrolytic rectifier (1926).  In his doctoral studies he worked on analog computers with Vannevar Bush, developing the  Differential Analyzer.  His Sc.D., advised by Bush, was entitled The Extension and Application of Differential Analyzer Technique in the Solution of Ordinary Differential Equations (1933). 

In 1934, he joined the faculty of the electrical engineering department as an assistant professor.

World War II and Later Work
During World War II, Caldwell was a chief within the fire control section of the National Defense Research Committee. For his work during WWII, he earned a Medal for Merit, the Naval Ordnance Development Award, and the King's Medal for Service in the Cause of Freedom from Great Britain. At the time, the Medal for Merit was the highest civilian honor granted by the United States.

Caldwell was a pioneer in logic circuits.

After the war, he led the MIT Center of Analysis, where he reluctantly gave way to digital computing by initiating the Rockefeller Electronic Computer (RED) and supporting the Project Whirlwind.  The centre closed around 1950, after which Caldwell continued as a faculty member, being the advisor to both David A. Huffman (1953) and Edward J. McCluskey (1956).

In 1959, Caldwell published a paper describing his work on the Sinotype (also known as the Ideographic Composing Machine) which was one of the first efforts at typesetting and compositing the Chinese language with a computer. Using a QWERTY keyboard, a Sinotype user could input the brush strokes of which Chinese characters are composed (not their phonetic values). Sinotype has been described as the first instance of autocomplete. It was prototyped by the Graphic Arts Research Foundation (GARF).

Publications
 William H. Timbie and Henry Harold Higbie and Caldwell, Essentials of alternating currents, Wiley, 1939
 Electrical Engineering Research at M.I.T. : an appreciation MIT, 1948
 Analog and special purpose computing machines 1949
  (xviii+686 pages)

References

American electrical engineers
MIT School of Engineering alumni
MIT School of Engineering faculty
1904 births
1960 deaths
20th-century American engineers
Recipients of the King's Medal for Service in the Cause of Freedom
Medal_for_Merit_recipients
Belgian Railways Class 19. Class 19 is a class of electric locomotives operated by NMBS/SNCB, the state train operator of Belgium.

During 1993 Class 21 locomotive 2130 was converted for use as a test bed for the development of future class 13.

It was renumbered into Class 19 as 1901 for the testing program and was the only member of the class. The traction motors were replaced with asynchronous motors. It also gained a transformer that let it work under 25000 volts, 50 Hz AC and French signalling and train protection systems. The 3000 Volts DC capability was retained. The reason for this was because Class 13 was to be a dual voltage locomotive running on the same voltages with the same type of motors. 1901 operated into Lille Flandres station in France many times as part of the testing process. By 2001 the testing was completed and it was restored to standard with its original number of 2130.

In 2014, NMBS/SNCB decided to stop the first half of Class 21 (2101-2130). Part of this was because they had too many electric locomotives and part of it was because there was a need for otherwise unobtainable spare parts to keep Class 27 in service. These Class 21s will have their asbestos removed and be stripped of parts and scrapped in the near future. The second half of Class 21 is expected to meet the same fate by the end of 2015.

References

External links 
 HLE 19

Electric locomotives of Belgium
3000 V DC locomotives
25 kV AC locomotives
Bo′Bo′ locomotives
Railway locomotives introduced in 1993
National Railway Company of Belgium locomotives
Standard gauge locomotives of Belgium
Bo′Bo′ electric locomotives of Europe
Rolanet. Rolanet (Robotron Local Area Network) was a networking standard, developed in the former German Democratic Republic (GDR) and introduced in 1987 by the computer manufacturer Robotron. It enabled computer networking over coax cable and glass fiber with a range of . Networking speed was 500 kBd, comparable to other standards of the day. A maximum of 253 computers could be connected using Rolanet.

Two variants of Rolanet existed:
 Rolanet 1, introduced in 1987, saw limited deployment;
 Rolanet 2 was planned as a successor to Rolanet 1, but presumably never got beyond the prototype stage.

A scaled-down version of Rolanet, BICNet, was used for educational purposes.

It is no longer possible to assemble a functioning Rolanet system today, due to lack of software and working hardware.

External links 
  More information about Robotron networking technologies on Robotrontechnik.de

Computer networking
Science and technology in East Germany
Frederic Thomas Nicholls. Frederic Thomas Nicholls (November 22, 1856 – October 25, 1921) was a Canadian businessman, electrical engineer and politician. He was a Conservative senator representing the senatorial division of Toronto, Ontario from 1917 to 1921.

In 1892 Nicholls became second vice-president and general manager of Canadian General Electric. He was president of the National Electric Light Association of the United States in 1896–97 and brought its annual convention to Niagara Falls, Ontario, in 1897.

Frederic Nicholls was a member of Edison Pioneers and Ontario Hydro. He worked on the Toronto Power Company Plant with Dr. Frederick Stark Pearson of the Pearson Engineering Corporation of New York. The Toronto Power station was opened in 1906 by the Electrical Development Company of Ontario, led by Toronto Billionaire financier Henry Pellatt, who owned that city's Casa Loma. Pellatt hired the same architect, Edward J. Lennox to design both his home and his hydroelectric generator in Niagara Falls.

Pellatt and partners William Mackenzie and Frederic Thomas Nicholls formed the Electrical Development Company of Ontario in 1903, buying water rights from the Niagara Parks Commission for $80,000 a year.

Nicholls was one of the directors along with William Mackenzie and Wilmot Deloui Matthews to form the Canadian Shipbuilding Company with capital of $1 million in the early 1900s ($21,733,333 in 2018).

Recognition and influence

The Nicholls Building on King Street in Toronto, Ontario, Canada is named after him including the Nicholls Oval and Nicholls Lake in Ontario. He was also known as an early editor of the Toronto Star newspaper. Frederic Nicholls's speech of January 19, 1905, to the Empire Club in Toronto was published as Niagara's power: past, present, prospective . . . ([Toronto, 1905], reproduced as CIHM, no.78710). A number of his other speeches are in his Conservation of Canadian trade (Toronto, 1918).

References

External links
 

1856 births
1921 deaths
Canadian businesspeople
Canadian senators from Ontario
English emigrants to Canada
Conservative Party of Canada (1867–1942) senators