omniomni/omni-engineering huggingface dataset:
Wafer bonding. Wafer bonding is a packaging technology on wafer-level for the fabrication of microelectromechanical systems (MEMS), nanoelectromechanical systems (NEMS), microelectronics and optoelectronics, ensuring a mechanically stable and hermetically sealed encapsulation. The wafers' diameter range from 100 mm to 200 mm (4 inch to 8 inch) for MEMS/NEMS and up to 300 mm (12 inch) for the production of microelectronic devices. Smaller wafers were used in the early days of the microelectronics industry, with wafers being just 1 inch in diameter in the 1950s.

Overview 
In microelectromechanical systems (MEMS) and nanoelectromechanical systems (NEMS), the package protects the sensitive internal structures from environmental influences such as temperature, moisture, high pressure and oxidizing species. The long-term stability and reliability of the functional elements depend on the encapsulation process, as does the overall device cost. The package has to fulfill the following requirements:
 protection against environmental influences
 heat dissipation
 integration of elements with different technologies
 compatibility with the surrounding periphery
 maintenance of energy and information flow

Techniques 
The commonly used and developed bonding methods are as follows:
 Direct bonding
 Surface activated bonding
 Plasma activated bonding
 Anodic bonding
 Eutectic bonding
 Glass frit bonding
 Adhesive bonding
 Thermocompression bonding
 Reactive bonding
 Transient liquid phase diffusion bonding
 Atomic diffusion bonding

Requirements 
The bonding of wafers requires specific environmental conditions which can generally be defined as follows:

 substrate surface
 flatness
 smoothness
 cleanliness
 bonding environment
 bond temperature
 ambient pressure
 applied force
 materials
 substrate materials
 intermediate layer materials

The actual bond is an interaction of all those conditions and requirements. Hence, the applied technology needs to be chosen in respect to the present substrate and defined specification like max. bearable temperature, mechanical pressure or desired gaseous atmosphere.

Evaluation 
The bonded wafers are characterized in order to evaluate a technology's yield, bonding strength and level of hermeticity either for fabricated devices or for the purpose of process development. Therefore, several different approaches for the bond characterization have emerged. On the one hand non-destructive optical methods to find cracks or interfacial voids are used beside destructive techniques for the bond strength evaluation, like tensile or shear testing. On the other hand, the unique properties of carefully chosen gases or the pressure depending vibration behavior of micro resonators are exploited for hermeticity testing.

References

Further reading 
Peter Ramm, James Lu, Maaike Taklo (editors), Handbook of Wafer Bonding, Wiley-VCH, .

 
Electronics manufacturing
Packaging (microfabrication)
Semiconductor technology
Chemical bonding
Bismuth silicon oxide. Bismuth silicon oxide is a solid inorganic compound of bismuth, silicon and oxygen. Its most common chemical formula is Bi12SiO20, though other compositions are also known. It occurs naturally as the mineral sillénite and can be produced synthetically, by heating a mixture of bismuth and silicon oxides. Centimeter-sized single crystals of Bi12SiO20 can be grown by the Czochralski process from the molten phase. They exhibit piezoelectric, electro-optic, elasto-optic, photorefractive and photoconductive properties, and therefore have potential applications in spatial light modulators, acoustic delay lines and hologram recording equipment. Bi12SiO20 can be obtained as a whitish powder with band gap of approximately 3.2 eV starting from bismuth subcarbonate and silica in presence of ethyleneglycol. 29Si solid-state NMR is used to proof that the Si(IV) cations are sharing oxygen atoms with the Bi(III) cations. The 29Si chemical shift (δ) in Bi12SiO20 is −78.1 ppm. Unlike the bismuth oxide, the presence of the acidic Si(IV) cations avoid the reactivity with CO2.

Another bismuth silicate has formula Bi2O9Si3.

References

Bismuth compounds
Inorganic silicon compounds
Oxides
Motorsport Industry Association. The Motorsport Industry Association is the global trade association for the motorsport industry and is based in the United Kingdom. Most top-level motorsport constructors are based in the UK. Around 75% of motorsport research and development takes place in the UK.

History
The Motorsport Industry Association (MIA) is a global trade association for the motorsport, performance engineering, services and tuning sectors. The MIA represents the specialised needs of this highly successful global industry as it undergoes continuing rapid development throughout the world.

Although most of the British motorsport industry is based in the so-called Motorsport Valley (the name comes from Silicon Valley) in Northamptonshire and Oxfordshire, around the Silverstone Circuit, the organisation is in Warwickshire. Motorsport Valley is a registered trade mark of the Motorsport Industry Association, owned by them on behalf of its members.

Function
It represents the UK motorsport industry at a national level. Around 4,000 companies in the UK are involved in the motorsport industry, with an annual turnover of around £9 billion,  with around 70% being exports. It spends 30% of turnover on research and development. There are around 25,000 qualified engineers involved in the UK industry.  The MIA was started by Brian Sims, ex-Marketing Director of F1 Benetton and Lola and the current CEO, Chris Aylett took over in 1997.

National Motorsport Week – running from the end of June each year – is a special celebration of UK motor sport jointly promoted by the Motorsport Industry Association (MIA) and the Motor Sports Association (MSA) and starts with the Goodwood Festival of Speed and finishes with the British Formula One Grand Prix at Silverstone.

Structure
In April 1994, leading personalities in British motorsport joined forces to form their own trade association - the MIA - with the aim of promoting one of the UK's most successful industries - motorsport. The original concept was proposed by Founder and original CEO, Brian Sims, with the first Executive Committee comprising Rob Baldock (Accenture); Dick Scammel (Cosworth);Tony Schulp (Haymarket); John Kirkpatrick (Jim Russell Racing Drivers School); Tony Panaro (Euro Northern Travel) and Tony Fletcher (Premier Fuels).

The Rt Hon the Lord Astor of Hever, PC, DL accepted the role of Honorary MIA President for a second time when his term as a Defence Minister ended in 2015.

The MIA has embraced an ever-expanding international network of business contacts, the result being that today it boasts nearly 400 Global members, whose companies transact more than £9 billion of motorsport business worldwide.

See also
 Formula One Group
 Formula One Constructors Association
 Motor Sports Association - governing body
 Automotive industry in the United Kingdom
 Glossary of motorsport terms

References

External links
 MIA

Motorsport organisations in the United Kingdom
British racecar constructors
Organisations based in Warwickshire
Trade associations based in the United Kingdom
Organizations established in 1994
1994 establishments in the United Kingdom
Sports organisations of the United Kingdom
Briegleb BG-7. The Briegleb BG-7 is an American strut-braced high-wing, single seat glider that was designed by William G. Briegleb and produced by the Sailplane Corporation of America as a completed aircraft and also as a kit.

Design and development
The BG-7 was a development of the 1939 BG-6, with longer, semi-tapered wings of  span, compared to the  wing on the earlier model.

The BG-7 wing is made from wood structure, with two spars and covered in doped aircraft fabric. The wing is supported by dual struts. The fuselage is made from steel tube, again with fabric covering and the tail is metal and fabric. The longer wing created stability issues and many aircraft were subsequently modified by either lengthening the tail to increase the tail arm or enlarging the vertical fin. Cockpit modifications were also common.

Three BG-7s were completed by the factory and a further 20 kits were sold. The type was never certified and most were amateur-built from factory kits.

Operational history
In 1952 Betsy Woodward Proudfit, flying a BG-7, set the feminine speed record for the  triangle, at . The record stood for eighteen years.

In March 2011 there were still 2 BG-7s on the Federal Aviation Administration register.

Specifications (BG-7)

See also
Briegleb El Mirage Airfield

References

1940s United States sailplanes
BG-7
Aircraft first flown in 1940
Decamethylferrocene. Decamethylferrocene or bis(pentamethylcyclopentadienyl)iron(II) is a chemical compound with formula  or .  It is a sandwich compound, whose molecule has an iron(II) cation  attached by coordination bonds between two pentamethylcyclopentadienyl anions (, ). It can also be viewed as a derivative of ferrocene, with a methyl group replacing each hydrogen atom of its cyclopentadienyl rings.  The name and formula are often abbreviated to DmFc,   or .

This compound is a yellow crystalline solid that is used in chemical laboratories as a weak reductant. The iron(II) core is easily oxidized to iron(III), yielding the monovalent cation decamethylferrocenium, and even to higher oxidation states.

Preparation 
Decamethylferrocene is prepared in the same manner as ferrocene from pentamethylcyclopentadiene. This method can be used to produce other decamethylcyclopentadienyl sandwich compounds.
2 Li(C5Me5) + FeCl2 → Fe(C5Me5)2 + 2 LiCl

The product can be purified by sublimation.  has staggered  rings. The average distance between iron and each carbon is approximately 2.050 Å. This structure has been confirmed by X-ray crystallography.

Redox reactions 
Like ferrocene, decamethylferrocene forms a stable cation because Fe(II) is easily oxidized to Fe(III). Because of the electron donating methyl groups on the  groups, decamethylferrocene is more reducing than is ferrocene. In a solution of acetonitrile the reduction potential for the  couple is −0.59 V compared to a  reference (−0.48 V vs Fc/ in ). Oxygen is reduced to hydrogen peroxide by decamethylferrocene in acidic solution.

Using powerful oxidants (e.g.  or  in , or  in ) decamethylferrocene is oxidized to a stable dication with an iron(IV) core. In the  salt, the  rings are parallel. In contrast, a tilt angle of 17° between the  rings is observed in the crystal structure of the  salt.

References 

Ferrocenes
Pentamethylcyclopentadienyl complexes
One-electron reducing agents
Metallocenes
Hiuchi-class support ship. The Hiuchi class support ship is designed to provide Auxiliary Multi-purpose Support (AMS) for the Japanese Maritime Self-Defense Force (JMSDF).

The Hiuchi AMS class replaced the Auxiliary Service Utility class (ASU). The primary mission of these vessels is to support training exercises of other ships, including shooting practice and torpedo launching practice.

Ships in the class

Notes

References
 Werth, Eric. (2007). Naval Institute Guide to Combat Fleets of the World: Their Ships, Aircraft, and Systems.  Annapolis: Naval Institute Press. ;

External links
  多用途支援艦「ひうち」型
 Ministry of Defense,  Press Conference by the Defense Minister (11:11-11:26 A.M. March 25, 2011)

 
Auxiliary training ship classes
Don Bosco Institute of Technology, Bengaluru. Don Bosco Institute of Technology (DBIT) is a college located in Kumbalagodu Village, Bangalore. In 2001, Don Bosco Institute of Technology, was established on a rambling sylvan area of about  campus, about  away from Kengeri bordering the Bangalore–Mysore Road. DBIT provides civil, mechanical, engineering technology, computer and management education.

It is run by the Salesians of Don Bosco.

See also
 Don Bosco College of Engineering

References

Engineering colleges in Bengaluru
Educational institutions established in 2001
2001 establishments in Karnataka
Tethered formation flying. Tethered formation flying is one of applications for space tethers. This sub-set represents an entire area of research using a non-conductive tether to connect multiple spacecraft.

Spacecraft formation flight is becoming a key research area, where distributed computation and decentralized control schemes, as well as information flows between elements, are explored. One such example includes stellar interferometers in which multiple apertures, in controlled formation, collect the light for coherent interferometric beam combinations, thereby achieving a fine angular resolution comparable to a large monolithic aperture telescope. The possible architectures of spaceborne interferometers include a structurally connected interferometer (SCI) Space Interferometry Mission, which allows for very limited baseline changes, and a separated spacecraft interferometer (SSI) Terrestrial Planet Finder, where the usage of propellant can be prohibitively expensive. A tethered-formation flight interferometer represents a balance between SCI and SSI. Such a system is currently being considered for NASA's Submillimeter Probe of the Evolution of Cosmic Structure (SPECS) mission. The dynamics of SSI are coupled by the definition of relative attitude whereas tethered formation spacecraft exhibit inherently coupled nonlinear dynamics.

The MIT Space Systems Laboratory conducted ground experiments that tested a fully decentralized nonlinear control law, which eliminates the need for inter-satellite communications.
Contraction theory
was used to prove that a nonlinear control law stabilizing a single-tethered spacecraft can also stabilize arbitrarily large circular arrays of tethered spacecraft, as well as a three-spacecraft inline configuration. In order to validate the effectiveness of the decentralized control and estimation framework, a new suite of hardware has been designed and added to the SPHERES (Synchronize Position Hold Engage and Reorient Experimental Satellite) testbed. A 2007 PhD thesis introduced a novel relative attitude estimator, in which a series of Kalman filters incorporate the gyro, force-torque sensor, and relative distance measurements.
The closed-loop control experiments can be viewed at .
The MIT team also reported the first propellant-free underactuated control results for tethered formation flight. This is motivated by a controllability analysis that indicates that both array resizing and spin-up are fully controllable by the reaction wheels and the tether motor.

References

External links 
 Experiments on tethered formation flying using SPHERES
 MIT SPHERES • Publications

Spacecraft components
BeijingWest Industries. BWI Group, also known as BeijingWest Industries, is a supplier of brake and suspension systems headquartered in  Beijing, China. The company acquired the Chassis Division of Delphi on November 1, 2009. The brake and suspension business lines were purchased for approximately $100 million. The company supplies to automotive, motorcycle, and specialty vehicle manufacturers. BWI Group is an international supplier with manufacturing facilities located in China, Poland, United Kingdom, Czech Republic and Mexico.

History
1909: Dayton Engineering Laboratories Co.
1918: Delco Products
1923: Moraine Products and Inland
1929: Delco Appliance Rochester
1936: Delco Brake
1969: Saginaw Manufacturing
1991: Delco Chassis
1995: Delphi Chassis Systems
2009: Beijing West Industries

Products
BWI Group's product history:
1920s: began to manufacture shock absorbers.
1930s: introduced their drum brake master cylinder
1940s: the all-welded shock absorber was introduced
1960s: the vacuum booster, disc brake and the air adjustable shock became part of the product line
1970s: the brake corner, suspension strut, aluminum master cylinder, and cast iron knuckle added more to the product offerings
1980s: Innovative products were offered, such as: ABS (anti-lock braking system), strut modules, and selectable ride 
1990s: More innovations came in the 1990s with products like: ESC, Real Time Damping, Integrated Chassis, and Aluminum Knuckles. The de Carbon brand was also acquired during this time. 
2000s: MagneRide became one of the company's top brands and ABS applications for motorcycles were also introduced.

References

External links 
 bwigroup.com

Manufacturing companies based in Beijing
Manufacturing companies established in 2009
Chinese companies established in 2009
Automotive industry in China

zh:京西重工国际
Computer Modelling Group. Computer Modelling Group Ltd., abbreviated as CMG, is a software company that produces reservoir simulation software for the oil and gas industry.  It is based in Calgary, Alberta, Canada with branch offices in Houston, Dubai, Bogota, Rio de Janeiro, London and Kuala Lumpur.  The company is traded on the Toronto Stock Exchange under the symbol CMG.

The company offers three reservoir simulation applications. IMEX, a conventional black oil simulator used for primary, secondary and enhanced or improved oil recovery processes; GEM, an advanced Equation-of-State (EoS) compositional and unconventional simulator;  and STARS a k-value thermal and advanced processes simulator. CMG also offers CMOST, a reservoir engineering tool that conducts automated history matching, sensitivity analysis and optimization of reservoir models. In addition, CMG has developed CoFlow, which is a unique production engineering software for wellbore and facility analysis and allows for smart coupling with reservoir models.

History
The company began in 1978 as an effort to develop a simulator by Khalid Aziz of the University of Calgary's Chemical Engineering department, with a research grant from the government of Alberta.  CMG became known for its expertise in heavy oil, and has expanded this knowledge into all aspects of reservoir flow and advanced processes modelling. A commercial product was available by the late 1980s.  For the first 19 years of the company's history it was a non-profit entity.  In 1997, CMG became a public company when it was listed on the TSX.  The company now claims over 570 clients in 58 countries.

In May 2018, CMG President and CEO Kenneth Dedeluk announced his retirement following the company. Ryan Schneider was appointed to succeed Dedeluk.

References

Companies listed on the Toronto Stock Exchange
Companies based in Calgary
Technology companies of Canada
Software companies of Canada
1978 establishments in Alberta
Canadian companies established in 1978
Software companies established in 1978
ASM-N-8 Corvus. The ASM-N-8 Corvus was an anti-radiation missile developed by Temco Aircraft for the United States Navy.

History
In April 1955, the U.S. Navy planned the acquisition of a long-range air-to-surface missile armed with a nuclear warhead. This weapon should be carried by the carrier-based North American A3J Vigilante and Douglas A4D Skyhawk. This missile was named ASM-N-8 Raven. Later that year, the project was changed to a nuclear armed anti-radar missile, and renamed Corvus. Temco Aircraft was awarded a development contract in January 1957. The first flight of an XASM-N-8 missile occurred in July 1959. By March 1960, fully guided flights had been made at the Pacific Missile Test Center at Point Mugu, California. However, the program was cancelled in July 1960, when the overall responsibility for long-range nuclear air-to-surface missiles was transferred to the United States Air Force, which had no use for the Corvus missile.

Specifications

The XASM-N-8 had two delta wings and cruciform tailfins for flight stability and control. It was powered by a Thiokol liquid-fueled rocket, which gave it a range of 315 km for high-altitude launches and 185 km for low-altitude launches. Normally the missile would use a passive radar seeker and home on shore-based and ship-based radars. It could also home on non-radiating targets which were illuminated by a radar of the launching aircraft. The Corvus missile was to be armed with a W-40 nuclear warhead of 10 kt yield.

Gallery

See also

References

ASM-N-008
ASM-N-008
ASM-N-8
Naval weapons of the United States
Ffair Fach Railway Cutting and River Section. Ffair Fach Railway Cutting and River Section is a cut in Wales that exposes the geology and fossils of the region. It is a Site of Special Scientific Interest in Carmarthen & Dinefwr,  Wales.

See also
List of Sites of Special Scientific Interest in Carmarthen & Dinefwr

References

Sites of Special Scientific Interest in Carmarthen & Dinefwr
Baker-McMillan Cadet. The Baker-McMillan Cadet is an American, high-wing, strut-braced, open-cockpit, single-seat glider that was designed in 1929 by Frank R. Gross and produced by Baker-McMillan (Different sources variously spell the company name Baker-MacMillen, Baker Macmillen or Baker MacMillen).

Design and development
The Cadet was designed by Dr. Gross, a former member of the Akaflieg Darmstadt, in 1929 as an improvement over the primary gliders then in use and as an aircraft that would offer soaring capability.

The Cadet is built with a steel tube fuselage and a wooden wing that is supported by dual parallel struts, with jury struts. The tail is a wire-braced wooded structure. The whole aircraft is covered in doped aircraft fabric covering.

At least 30 and perhaps as many as 40 Cadets were constructed.

Operational history
The Cadet was the first glider to be flown at Elmira, New York after Wolfgang Klemperer, Warren Eaton and Earl Southee surveyed the area and determined it had potential for soaring flights. One flight was flown by Jack O'Meara, a factory pilot for Baker-McMillan, who had a flight of one hour and 38 minutes from Elmira's South Mountain.

One Cadet was flown from water on twin floats. On another occasion four Cadets were towed aloft at the same time and released by a Goodyear Blimp over Akron, Ohio.

In March 2011 two Cadets remained on the Federal Aviation Administration registry.

Aircraft on display
National Soaring Museum - 1
Thermal G Museum, Waterford, Pennsylvania - 1

Specifications (Cadet)

See also

References

1920s United States sailplanes
Aircraft first flown in 1929
High-wing aircraft