omniomni/omni-engineering huggingface dataset:
TMM Avia T-10 Avia-Tor. The TMM Avia T-10 Avia-Tor is a single engine two seat Ukrainian light aircraft, with a high wing and transparent blister cabin doors for extra visibility, designed to be robust enough for a range of applications.

Design
The Avia-Tor is a conventionally arranged single engine high wing light aircraft, seating two side-by-side.  It was designed as a sport machine, with applications as a basic trainer, agricultural sprayer, patroller and air photographer.

It has constant chord wings built around two wooden spars with fibreglass ribs and synthetic fabric covering.  They are braced from the lower fuselage with V-struts on each side, assisted by further intermediate bracing.   Three position (0°, 10° and 40°) flaps are fitted.  The square sided fuselage has a stainless steel truss structure and is fabric covered apart from the glass fibre engine cowling and cabin roof.  The two upward hinged cabin doors are entirely transparent blisters for optimum visibility.  The empennage is formed from steel tubes with fibreglass ribs, all fabric covered.  The tailplane is wire braced from above to the fin with a pair of wires on each side and similarly below to the lower fuselage. The elevators are mass balanced and the port side one has a trim tab.  The rudder also has a tab.  Wings and tailplane can be easily folded for transport.

The Avia-Tor normally uses a fixed tricycle undercarriage, though floats or skis are options. Each mainwheel is supported by a V-pair of struts joined to the lower fuselage longerons and with a half-axle from wheel to the central fuselage.  A MVEN KS-500-2 Cobra ballistic parachute recovery system is standard.

Development
The first prototype flew in 2002 and was followed by four more T-10 pre-production aircraft.  These were followed by a batch of production T-10M machines for purchase as complete aircraft.  The production of kits may follow.

The T-10M has some changes to undercarriage and fin, plus a change of engine.  The main gear sprung element has been moved from the half-axle to the rearward V strut and the early castoring nosewheel replaced with a steerable system with a simpler single leg.  The fin of the T-10M is more angular and narrower than that of the T-10 and incorporates a triangular fillet.  The T-10s are powered by 60 kW (80 hp) Jabiru 2200s, the T-10Ms by 74 kW (100 hp) Rotax 912S flat four engines.

Operational history

Four of the five T-10 pre-production aircraft are currently on sale as T-10 Frigates. All five T-10s and one T-10M aircraft remain on the Ukrainian private aircraft register in mid-2010. Ukrainian certification was anticipated in 2009.

Engenious Aerospace Ltd (EAL) has the Indian dealership for the T-10.

Specifications

References

2000s Ukrainian civil aircraft
Lee L-1P-S "Little Mixer". The Lee L-1P-S "Little Mixer" is a single place parasol homebuilt aircraft designed and built in the 1950s.

Development
The "Little Mixer" is a modification of a homebuilt design and fuselage first constructed by Jim McManiman of Eugene, Oregon in 1930. The airframe was licensed under Oregon state rules, and predated McManiman's later design, the McManiman “Baby Fleet”.

Design
The Little Mixer is a high wing open cockpit parasol with a fabric covered steel tube fuselage. The cowling and landing gear are from a Piper J-3 model. The wings are all-wood with fabric covering.

Specifications (Lee L-1P-S "Little Mixer")

See also

Notes

References

Homebuilt aircraft
Articles containing video clips
Aircraft with fixed conventional landing gear
Single-engined piston aircraft
Parasol-wing aircraft
Single-engined tractor aircraft
Merdeka Building. Merdeka Building () is an Art Deco building in Jalan Asia-Afrika, Bandung, Indonesia. Today it serves as a museum displaying collections and photographs of the Asian–African Conference, the first Non-Aligned Movement event, which was held there in 1955.

Architecture 

The present building was designed in 1926 in Art Deco style by Van Galen and C.P. Wolff Schoemaker, both professors at Technische Hogeschool (today ITB) and famous architects of that time; a further extension was designed in 1940 in Streamline Moderne style by Albert Aalbers. The 7500 m² building had Italian marble floors, some saloon and rooms in cikenhout wooden finishing, and was adorned with crystal lamps on the ceilings.

History 

The first building on the site at the intersection of Braga Street and Jalan Asia-Africa was constructed in 1895 for the Sociëteit Concordia. In 1926 it was rebuilt by Wolff Schoemacher, Albert Aalbers and Van Gallen. The Sociëteit Concordia was the dance hall, entertainment and social gathering venue for rich people in Bandung and its vicinity. That included plantation owners or employees, officers, officials, and wealthy businessman. During weekends, the building was filled with people enjoying art performances, social dances and dinner.

During the Japanese occupation of the Dutch East Indies, the building was renamed Dai Toa Kaikan and served as cultural centre.

After the Indonesian proclamation of Independence on 17 August 1945, the building was used as headquarters of Indonesian independence fighters against Japanese troops.

After the recognition of Indonesian Independence by The Netherlands in 1949, and the formation of federal government of Negara Pasundan, Concordia building was once again used as public gathering hall, for art performances, parties, dances, and gala dinner. 

In 1954, the government of Indonesia appointed Bandung as the host of Asian–African Conference, the Concordia building chosen as the venue of this International conference. At that time Concordia was the largest and grandest hall in Bandung, with strategic location near Savoy Homann Hotel and Preanger Hotel in the city centre. In early 1955, the building was renovated to meet international conference requirements by Ir. R. Srigati Santoso, and renamed Gedung Merdeka (independence building). The building also served as Indonesian House of Representatives (DPR) convention building.

In 1965 the Gedung Merdeka was the venue for the Asian-African Islamic Conference. In 1971 all of the House of Representatives meetings and activities were moved to Jakarta. In March 1980 the building hosted the 25th anniversary of the Asian-African Conference, and the Asian-African Conference Museum was inaugurated by president Soeharto.

References

External links

Museum of the Asian-African Conference (Official site)

Museums in West Java
Buildings and structures in Bandung
Art Deco architecture in Indonesia
Dutch colonial architecture in Indonesia
Buildings and structures completed in 1926
Cultural Properties of Indonesia in West Java
Fundamental theorem of software engineering. The fundamental theorem of software engineering (FTSE) is a term originated by Andrew Koenig to describe a remark by Butler Lampson attributed to David J. Wheeler:

The theorem does not describe an actual theorem that can be proven; rather, it is a general principle for managing complexity through abstraction.

The theorem is often expanded by the humorous clause "…except for the problem of too many levels of indirection", referring to the fact that too many abstractions may create intrinsic complexity issues of their own. For example, the use of protocol layering in computer networks, which today is ubiquitous, has been criticized in ways that are typical of more general disadvantages of abstraction. Here, the adding of extra levels of indirection may cause higher layers to duplicate the functionality of lower layers, leading to inefficiency, and functionality at one layer may need data present only at another layer, which fundamentally violates the goal of separation into different layers.

References

Software engineering folklore
Carbotanium. Carbotanium is a combination of beta titanium alloy and carbon composite. It is commonly used in Pagani cars.

Properties 
It is a combination of beta titanium alloy with advanced carbon composites, having a matched yield strength and moduli of elasticity ratio. When the combination is adhesively bonded, both parts will approach maximum yield strength and fail at a similar amount of total strain. The components of carbotanium; carbon fiber and titanium, are woven together to form a strong, light material that can withstand significant amounts of heat and strain. This is because carbon fiber has the highest strength-to-density ratio of any current fiber and titanium has the highest strength-to-density ratio of any current metal. As a result, carbotanium can withstand temperatures up to 315 °C.  The material properties of carbotanium are a mixture of those of a titanium alloy and a carbon fiber.

Manufacturing 
The titanium and carbon composites are combined by first abrading the titanium to be bonded, coating the titanium with platinum. The titanium is then heated in an oven at 500 °C for several hours. A primer is then sprayed onto the coated titanium. Next, an adhesive is applied to the primer side of the titanium and then finally, the carbon is applied to the adhesive.

Usage

Carbotanium is a patented composite material invented by Modena Design, the carbon composite manufacturing and consultancy arm of the Italian car company Pagani. Pagani has applied this weave on select models of their extra strong and lightweight supercars, the Pagani Zonda R and Pagani Huayra. Although not all Pagani Zondas are manufactured to include carbotanium, some are built with carbon fibre structures and other variations of composite materials have been used.

References

Further reading 

Composite materials
Pagani (company)
Scouring pad. A scouring pad or scourer is a small pad of metal or plastic mesh used for scouring a surface. Some scouring pads have one side made of a soft sponge-like material and the other is the aforementioned mesh.

History
The scouring pad has been reincarnated in several forms over the years. In 1928, R. B. Kingman patented the scouring ball, which was one of the first scouring pads made of a metal mesh.

On 30 September 1941, United States patent 2,257,456 was issued to Joseph R. Crockford of Chicago, IL for a scouring device of the type employed for "cleansing and scouring pots, pans and other household implements." The invention provided for a "plate of non-corrosive metal, arched or curved to fit the fingers."

In 1942, David J. Kelman patented a toroidal metal scouring pad. This was, and still is, used as an abrasive scrubbing pad, however, it is becoming less common, as it removes non-stick surfaces off pans.

On June 19, 1962, Alfred Benjamin patented the stainless-steel scouring pad - United States patent 3,039,125. 

In 1988, the first scouring pad made of out sponge material was patented by Hans J. Hartmann. This enabled the scouring pad to float. To achieve this, he used a technique to thread the metal mesh through the sponge and wrap it around the outside. This was meant to stop the scouring pad from dropping to the bottom of the sink.

In 1973, the plastic needle surface (now more commonly used) was invented by Edward Mednick, who invented the new surface as a way of reducing the damage scouring pads did to non-stick surfaces. This technology and varieties thereon are what most scouring pads sold today are based upon.

Use

Using scouring pads on non-stick surfaces such as Teflon is not advisable as they may strip away the coating. It is advisable to use protective equipment such as rubber gloves when using scouring pads as this is known to prevent (or at least hide) any irritation caused by use.

See also
 Scotch-Brite, a brand of polymer-based scouring pad produced by 3M
 Brillo Pad
 S.O.S Soap Pad
 Chore Boy

References

Cleaning products
Chemigram. A chemigram (from "chemistry" and gramma, Greek for "things written") is an experimental piece of art where an image is made by painting with chemicals on light-sensitive paper (such as photographic paper).

The term Chemigram was coined in the 1950s by Belgian artist Pierre Cordier.

History
Johann Schulze is regarded as the first to obtain a chemigram-like image; in 1725, he produced such a work using opaque paper and a bottle of silver salts. Hippolyte Bayard produced another chemigram-like image during sensitization tests he conducted in 1839. In the 1930s and 1940s, the German Edmund Kesting and the French Maurice Tabard produced pictures by painting with developer and fixer on photographic paper. It is the Belgian artist Pierre Cordier (born 1933), however, who has been most responsible for developing and exploring chemigrams. From his early days, in 1956, he was one of its rare practitioners, and contributed to its development by expanding its technical and esthetic possibilities. He adopted the name  in French in 1958 (chemigram in English and Dutch,  in German,  in Italian, and  in Spanish and Portuguese), the most widely accepted designation today. In 1974 Josef H. Neumann advanced the process in his chemograms by incorporating optical elements before applying chemicals.

Process

A chemigram is made by painting with chemicals on photographic paper and lies within the general domain of experimentation in the visual arts. It requires the use of materials from silver halide-based photography (light-sensitive paper, developer, and fixer), but it is not a photograph. Like the photogram, the chemigram is made without a camera, yet it is created in full light instead of in the darkness of the darkroom.  For this reason it is not "light that writes" (photo graphein in the Greek) but rather "chemistry that writes".

Chemigrams can be made solely with photo paper, developer, and fixer, with results that will somewhat resemble watercolor. The possibilities can be multiplied by using materials from painting (such as varnish, wax, or oil), These kinds of experiments are akin to those of Paul Klee, Max Ernst, and Antoni Tàpies.

In contrast to chemigrams, the production of chemograms consists of two different steps. First an enlarger is used to partly or fully expose a photographic image onto photographic paper in the darkroom and thereafter the images are processed with chemicals under full light.

Notes

References

External links

 "Camera-less photography" from the Victoria and Albert Museum

Photographic techniques
Fokker PW-5. The Fokker PW-5 (designated Fokker F VI by Fokker) was a Dutch fighter aircraft of the 1920s.  It was a parasol monoplane of which  twelve were built for the US Army Air Service, being used as advanced trainers.

Design and development

In 1921, the US Army Air Service evaluated the Fokker D.VIII parasol monoplane, and the D.VII biplane, both fighters handed over to it after the Armistice with Germany that ended World War I. It placed an order for two examples of a parasol monoplane fighter based on the design of the D.VIII, but powered by an American-built Hispano-Suiza V-8 engine, for evaluation. These aircraft, designated by Fokker as Fokker F VI, had plywood-covered wooden cantilever wings similar to those in the D.VIII and the contemporary D.X fighters, and a typical Fokker welded steel-tube fuselage. The forward fuselage was protected by armour plates, although the car-type radiator and the wing-mounted fuel tank had no such protection. The aircraft had a fixed tailskid undercarriage, while it had no fixed fin, having a balanced rudder instead.

Operational history
In 1921, the two evaluation examples were delivered in 1921, although one of them crashed on 13 March 1922 when its wing failed owing to flutter. An order for a further 10 aircraft was placed, and delivered later in 1921, the aircraft being used as advanced trainers by the 1st Pursuit Group.

Operators

US Army Air Service
1st Pursuit Group.

Specifications (PW-5)

See also

Notes

References

 Dorr, Robert F. and David Donald. Fighters of the United States Air Force. London:Temple Press/Aerospace, 1990. .
 Green, William and Gordon Swanborough. The Complete Book of Fighters. New York:Smithmark, 1994. .
 Weyl, A. R. Fokker: The Creative Years. London:Putnam, 1965.

External links

 Photo

1920s Dutch fighter aircraft
PW-05
Aircraft first flown in 1921
Parasol-wing aircraft
Pop's Props Cloudster. The Pop's Props Cloudster is a single seat, open-cockpit, parasol wing, single-engine monoplane, that was first flown in 1995. The aircraft was produced by Pop's Props of Cooksville, Illinois and made available as plans or in kit form. The company is no longer in business and kit production has been transferred to Simplex Aeroplanes of Old Saybrook, Connecticut.

The aircraft was designed for the FAR 103 Ultralight Vehicles category, including the category's  empty weight limit. The standard empty weight of the Cloudster is .

Design and development
The aircraft was designed for safe low and slow flying from unimproved surfaces.

The Cloudster is constructed of wood and covered in aircraft fabric. The landing gear is conventional with sprung main gear and a tailwheel. The wing is strut-braced with two parallel main struts and jury struts per side. Available engines include the liquid-cooled engine Kawasaki 340-LC of , the Half VW of  as well as several Rotax and Cuyuna engines. The designer recommended power range is .

Due to the laborious wood and fabric construction, builder completion time is estimated at 400 man-hours from the kit. The kit can be ordered as one kit or as several sub-kits.

The Cloudster was later developed into the Zing.

Variants
Pop's Props Cloudster
Original version with  wingspan and  stall speed.
Simplex Cloudster
Improved version with  wingspan and  stall speed introduced in February 2011. The wing was shortened to reduced adverse yaw effects.

Specifications (Pop's Props Cloudster)

See also

References

External links

1990s United States ultralight aircraft
Homebuilt aircraft
Cloudster
High-wing aircraft
Single-engined tractor aircraft
Aircraft first flown in 1995
Pop's Props Zing. The Pop's Props Zing is a single seat, open-cockpit, parasol wing, single-engine monoplane, first flown in 1996. The aircraft was designed by Scott Land and  produced by Pop's Props of Cooksville, Illinois in the form of plans and an aircraft kit. The company is no longer in business and the aircraft kit is now available from Simplex Aeroplanes of Old Saybrook, Connecticut.

The aircraft was designed for the FAR 103 Ultralight Vehicles category, including the category's  empty weight limit. The standard empty weight of the Zing is .

Design and development
The Zing was designed as a higher performance version of the Cloudster, with a smaller wing with a span  less than the Cloudster, yielding higher cruise speeds at the price of a higher stall speed.

The Zing is constructed of wood and covered in aircraft fabric. The landing gear is conventional with sprung aluminum main gear and a steerable tailwheel. The double surfaced wing is strut-braced with two parallel main struts and jury struts per side. The wing features 60% span ailerons and the whole wing can be removed for transport or storage. Available engines include the Kawasaki 340-LC liquid-cooled engine of , the Half VW of  as well as several Rotax engines. The designer recommended power range is .

Due to the laborious wood and fabric construction, builder completion time is estimated at 300-500 man-hours from plans or 200 man-hours from the kit. The kit is available as a single kit or as several sub-kits.

Specifications (Zing)

See also

References

External links

Photo of the Zing

1990s United States ultralight aircraft
Homebuilt aircraft
Zing
Parasol-wing aircraft
Single-engined tractor aircraft
Aircraft first flown in 1996
Metal nitrido complex. Metal nitrido complexes are coordination compounds and metal clusters that contain an atom of nitrogen bound only to transition metals.  These compounds are molecular, i.e. discrete in contrast to the polymeric, dense nitride materials that are useful in materials science.  The distinction between the molecular and solid-state polymers is not always very clear as illustrated by the materials Li6MoN4 and more condensed derivatives such as Na3MoN3.  Transition metal nitrido complexes have attracted interest in part because it is assumed that nitrogen fixation proceeds via nitrido intermediates.  Nitrido complexes have long been known, the first example being salts of [OsO3N]−, described in the 19th century.

Structural trends
Mononuclear complexes feature terminal nitride ligands, typically with short M-N distances consistent with metal ligand multiple bonds.  For example, in the anion in PPh4[MoNCl4], the Mo-N distance is 163.7 pm.  The occurrence of terminal nitrido ligands follow the patterns seen for oxo complexes: they are more common for early and heavier metals. Many bi- and polynuclear complexes are known with bridging nitrido ligands. More exotic metal nitrido complexes are also possible, such as a recently reported compound containing a terminal uranium nitride (-U≡N) bond.

Preparative routes
Metal nitrides are produced using a variety of nitrogen sources.  The first example above is prepared from amide (NH2−) as the N3− source:
OsO4  +  KNH2   →  KOsO3N  +  H2O
Most commonly however, nitrido complexes are produced by decomposition of azido complexes.  The driving force for these reactions is the great stability of N2. Nitrogen trichloride is an effective reagent to give chloro-nitrido complexes. In some cases, even N2 and nitriles can serve as sources of nitride ligands.

Reactions of nitrido ligands
The nitride ligand can be both electrophilic and nucleophilic. Terminal nitrides of early metals tend to be basic and oxidizable, whereas nitrides of the later metals tend to be oxidizing and electrophilic.  The former behavior is illustrated by their N-protonation and N-alkylation.  Ru and Os nitrido complexes often add organophosphines to give iminophosphine derivatives containing the R3PN− ligand.

Interstitial nitrides
Owing to the ability of nitrido ligands to serve as a bridging ligand, several metal clusters are known to contain nitride ligands at their center.  Such nitrido ligands are termed interstitial.  In some cases, the nitride is completely encased in the center of six or more metals and cannot undergo reactions, although it contributes to the intermetallic bonding.

See also
Abiological nitrogen fixation
Transition metal dinitrogen complex

General references

Inorganic chemistry
Coordination complexes
Charles Gerald McNamara. Charles Gerald McNamara (born 1900) was an Irish engineer active throughout mid-twentieth-century Ireland. He was the eldest son of T.F. McNamara.

Educated at the University School and Belvedere College, Dublin, he began his career with his younger brother N.P. McNamara at his father's practice. He earned a bachelor's degree in engineering from University College, Dublin in 1922; thereafter working in the Office of Public Works. In 1936, he established his own practice and incorporated his father's practice into his own following T.F. McNamara's death in 1947, creating the firm of C.G. McNamara & Partners with N.R. MacGovern as a new partner in the architectural division. He died in 1965 or 1966.

References

1900 births
Irish civil engineers
Engineers from County Dublin
Alumni of University College Dublin
Year of death missing
People educated at Belvedere College
20th-century Irish engineers