omniomni/omni-engineering huggingface dataset:
North 21st Street Bridge. The North 21st Street Bridge in Tacoma, Washington was built in 1910. It was designed by engineers Waddell & Harrington and is a continuous concrete rigid-frame girder bridge. It is significant as one of the very earliest examples of its type. It was built "almost simultaneously" with the  Asylum Avenue Aqueduct in Knoxville, Tennessee, which was documented by Carl W. Condit to be the first continuous concrete girder bridge to be built.

It has three  reinforced concrete spans with four continuous girders. Its spans are supported by reinforced concrete columns and abutments. The bridge has "massive and over-designed" slabs ( deep) and beams from  wide, from  deep. It is  wide to accommodate trolley tracks in the middle.

The bridge was listed on the National Register of Historic Places in 1982.

See also
List of bridges documented by the Historic American Engineering Record in Washington (state)
List of bridges on the National Register of Historic Places in Washington (state)
North 23rd Street Bridge, similar, nearby, narrower, longer, also designed by Waddell & Harrington, and also NRHP-listed

References

External links

Bridges in Tacoma, Washington
Concrete bridges in the United States
Girder bridges in the United States
Historic American Engineering Record in Washington (state)
National Register of Historic Places in Tacoma, Washington
Road bridges on the National Register of Historic Places in Washington (state)
London District Telegraph Company. The London District Telegraph Company was formed in 1859.  It was renamed the London and Provincial Telegraph Company  in 1867.

The management were connected with the British and Irish Magnetic Telegraph Company and the firm aimed to compete with the dominant Electric Telegraph Company in the London area. Its original Chairman was the banker and Member of Parliament Samuel Gurney (1816–1882). It used a combination of underground and overhead wires and saved money by avoiding the need for an Act of Parliament to authorise its activities. The overhead wires, however, required negotiation with individual households and landowners and were vulnerable to damage in bad weather. The firm employed many female clerks who were supervised by a "Matron" and "Sub Matrons".

In 1860 the company agreed with the Astronomer Royal to relay the Greenwich Observatory time-signal to all of its offices.

Despite an extensive network of lines in London, the company never made a net profit and only once an operating profit. It was acquired by the Postmaster General in the general nationalisation of private telegraph companies under the Telegraph Act 1868.

The company issued a number of telegraph stamps which are of interest to philatelists.

See also
List of historical British telcos

References

Telegraph companies of the United Kingdom
1859 establishments in England
Defunct telecommunications companies of the United Kingdom
British companies established in 1859
Telecommunications companies established in 1859
British companies disestablished in 1868
Technology companies disestablished in 1868
Telecommunications companies disestablished in the 19th century 
1868 disestablishments in England
Equivalent Concrete Performance Concept. According to the Equivalent Concrete Performance Concept a concrete composition, deviating from the EN 206-1, can still be accepted, provided that certain conditions are fulfilled.

Conditions 
A concrete composition not composed by the standard EN 206–1, can be acknowledged, only if the new concrete shows a performance equal to the standardized concrete concerning environmental classes. Cement content and water-cement ratio are important elements hereby.
The comparison with standardized concrete is tested according to the following properties:
Compressive strength
Resistance to carbonatation
Chloride migration
Freeze-thaw resistance
Other possible requirements

When the new concrete scores equally or better, a certificate of utilization can be obtained from certificating organizations.

Standardization 
The valid standards concerning concrete are:
 EN 206-1: determines minimum requirements of concrete composition for different environmental classes.
 NBN B15-100: Belgian annex
 CUR recommendation 48: Dutch annex

These national annexes serve to elaborate the functional description of the Equivalent Concrete Performance Concept.

Concrete composition 
Standardized concrete is a highly durable material, predominantly thanks to the increasing amount of cement at stricter environmental classes. But cement is a costly component and has a relatively powerful impact on the environment. 
Partly because of this, alternative binders such as fly ashes and slags are applied in the concrete sector. As a result, the content of Portland cement can be reduced in many cases. Other recycled raw materials can also contribute to a more economic or less environmental polluting concrete composition. 
1. Usage of residual products from the concrete industry, for example stone dust (from crushing aggregates), concrete slurry (from washing mixers) or concrete waste
2. Usage of residual products from other industries, for example fly ash from coal plants and slags from the metallurgical industry
3. Usage of new types of cement with reduced environmental impact (mineralized cement, limestone addition, waste-derived fuels)

Durability 
To respect the Kyoto Protocol, the -emission should be reduced.
Green concrete exists out of recycling or is composed is such a manner, that it is as environmental-friendly as possible.
A few conditions before the term green concrete may be used:
 -emission by concrete manufacturing is reduced by 30%
 Concrete contains at least 20% residual products, used as aggregates
 New residual products, previously disposed of, are used in concrete production
 -neutral: waste-derived fuels replace at least 10% of the fossile fuels in cement production

References 
 Equivalent Performance Concept: green concrete
 Betonlexicon: Duurzaamheid van beton
 Brancheorganisatie van de betonmortelindustrie
 Maatschappelijk Verantwoord Ondernemen Nederland

Concrete
Pfinder. Pfinder is a computer vision system which detects features in video images in order to recognize human figures and their movements and gestures.  Pfinder was designed by Wren, et al. of the MIT Media Laboratory in 1997.  As described by its authors, Pfinder is a "real-time system for tracking people and interpreting their behavior".  The system improves upon previous works by not only identifying the boundaries of a person in the image, but also analyzing the regions inside the boundaries and relating them to the known structure of the human body.  As an example, Pfinder can track a person's head and hands, and can determine the pose of the body and recognize gestures.

Limitations 
 Pfinder does not cope with multi-modal backgrounds, in which a histogram of the pixel intensity contains more than one distinct peak.
 While it can handle small or gradual changes in lighting, it does not react well to large, sudden lighting changes.  When there are large lighting changes, the system mistakenly labels them as a part of the foreground, and therefore tries to incorporate them into the human figure model.
 Pfinder is not able to handle multiple people in the same image well.  While the blobs representing each person would be detected, the system would attempt to analyze them as one distinct human figure.

Applications 
 Pfinder has been applied to the recognition of American Sign Language

See also 
 Background subtraction

References 

Computer vision software
Optical tracer. An optical tracer is an X-Y tooling machine which utilises a photoeye to track toolpaths printed on a full-scale drawing and move a tool head accordingly. No Z-axis or cut commands can be read from the drawing, so an operator was still required to tell the machine, when and how deep it should cut.

It has been made largely obsolete by CNC systems.

See also
Polygraph
CNC

Machine tools
John Najjar. John Najjar (;  – ) was an American designer and executive stylist at Ford Motor Company. He is credited for having co-designed the first prototype of the Ford Mustang known as Ford Mustang I with Philip T. Clark.

Career
Najjar was born to a Greek Orthodox Christian Lebanese family in Omaha, Nebraska. He joined Ford Motor Company's Apprentice School in Dearborn, Michigan. While working there as a machinist, he was approached by Henry Ford during a plant tour who asked him if he enjoyed his work. Najjar's response that he'd "rather be drawing cars" led to an invitation for him to add his talents to Ford's newly created Design Center.

He continued working as a designer for Ford for over 40 years. He worked with E. T. Gregorie, George Walker, Elwood Engel, Gene Bordinat, and Lee Iacocca. For many years his work was centered on futuristic show cars whose revolutionary features later appeared in many Ford, Lincoln and Mercury vehicles.

The Advanced Styling Studio developed the 1962 Ford Mustang I concept car - so named because of Najjar's love for its namesake, the North American P-51 Mustang fighter plane. His design contributions span decades and include the M4A3 Sherman tank and B-24 bomber in the 1940s, the 1957-58 Lincoln Continentals, the Mercury XM-800, the LevaCar concept

Najjar also co-designed jointly with fellow Ford Motor Company stylist Bill Schmidt the groundbreaking Lincoln Futura, a futuristic concept car, which debuted at the 1955 Chicago Auto Show. It that served as a base for the Batmobile for the 1966 TV series Batman, as well as for the first movie adaptation of the Batman comics.

Najjar and his wife Virginia retired to Sarasota, Florida, in 1985. Virginia died on March 29, 2005, while Najjar died on January 26, 2011.

References

Ford designers
American automobile designers
Artists from Omaha, Nebraska
People from Dearborn, Michigan
American people of Lebanese descent
People from Koura District
Members of the Greek Orthodox Church of Antioch
1918 births
2011 deaths
Ford people
Ford Mustang
Glossary of engineering: A–L. This glossary of engineering terms is a list of definitions about the major concepts of engineering. Please see the bottom of the page for glossaries of specific fields of engineering.

A

B

C

D

E

F

G

H

I

J

K

L

M–Z

See also

 Engineering
 National Council of Examiners for Engineering and Surveying
 Fundamentals of Engineering Examination
 Principles and Practice of Engineering Examination
 Graduate Aptitude Test in Engineering
 Glossary of aerospace engineering
 Glossary of civil engineering
 Glossary of electrical and electronics engineering
 Glossary of mechanical engineering
 Glossary of structural engineering
 Glossary of architecture
 Glossary of areas of mathematics
 Glossary of artificial intelligence
 Glossary of astronomy
 Glossary of biology
 Glossary of calculus
 Glossary of chemistry
 Glossary of ecology
 Glossary of economics
 Glossary of physics
 Glossary of probability and statistics

Notes

References

Works cited
 
 
 
 
 
 
 
 
 
 
 
 .
 
 

Engineering disciplines
Engineering
engineering
Engineering
Safety
Wikipedia glossaries using description lists
Underground personnel carrier. An underground personnel carrier is any heavy duty vehicle designed specifically for the safe transport of personnel and their supplies into underground work areas.  The most common underground applications is for the mining of either precious metal or coal.

Types

Narrow vein applications 
 5- and 7- man personnel carrier
Where tight turning in confined spaces is necessary, personnel carriers designed on tractors are common.  Heavy duty fenders, bumpers and man baskets (gondolas) are fabricated to mount on the tractor or tractor frames to provide more durability.
 Front loader personnel carrier

These personnel carriers use a front loader to perform various loader applications.  Also a front basket is typically attached to the front loader arms so that they may be lifted.  These carriers are typically built to carry 5 or 7 men.
 Towing personnel carriers

Some personnel carriers use a heavy duty hydraulic rear hitch that can two various attachments.  Towing PCs can be used in conjunction with a front loader as well.
 Attachments
Other narrow vein personnel carriers are designed for a specific job based on their attachments.  These attachments include rear and/or front lift baskets for utility and electrical work, mechanic packages, cable reels, heavy duty canes, ANFO loaders, and shotcrete booms.

Specialty built
These personnel carriers are designed and built from the ground up.  They are typically 5 man to 15 man carriers.  These carriers may also be designed using multiple attachments for job specific applications.

Low profile
In the coal mining industry low profile personnel carriers are the most commonly used.  These carriers may only have a  height dimension and carry up to 14 men, and are typically built from the ground up and can be designed with job specific attachments.

Mantrip

A mantrip is a shuttle for transporting miners down into an underground mine at the start of their shift, and out again at the end. Mantrips usually take the form of a train, running on a mine railway and operating like a cable car. Mantrips may also be self-powered, for example by a diesel locomotive. Other types of mantrips do not require a track and take the form of a pickup truck running on rubber tires. Because many mines have low ceilings, mantrips tend to have a reduced height.

In the United States, the Mine Safety and Health Administration has published safety regulations governing the operation of mantrips.

References

External links
 Kentucky Educational Television, Lexington, KY. "Mantrip." Electronic Field Trip to a Coal Mine. Accessed 2010-06-06.

Mining equipment
No. 5 Aircraft Depot RAAF. No. 5 Aircraft Depot RAAF was formed in 1942 at RAAF Station Forest Hill near Wagga Wagga, New South Wales, Australia.  The unit handled the major maintenance work on aircraft including the Bristol Beaufort, Bristol Beaufighter, Lockheed Ventura and the B-25 Mitchell. After the war, No 5 Aircraft Depot was disbanded.

Notes

References
 

5
5
City of Wagga Wagga
Type specimen (mineralogy). In mineralogy, the type specimen, also known as type material, is a reference sample by which a mineral is defined.  Similar to the biology type methods, a mineral type specimen is a sample (or in some cases a group of samples) of a mineral to which the scientific name of that mineral is formally attached. In other words, a type specimen is an example that serves to anchor or centralize the defining features of that particular mineral.

A mineral is a scientifically named set that includes some materials and excludes others, based on a detailed published description and on the provision of type specimens, which are usually available to scientists for examination in a major museum research collection, or similar institution.

History
Whereas the system of type specimens has long-existed in the biological sciences, this is not the case in mineralogy. The recentness of the practice means that sometimes no type material exists, even for minerals discovered as recently as the twentieth century. The publication of "Type specimens in  mineralogy" by P.G. Embrey and M.H. Hey in 1970 stimulated much discussion on type specimens, leading to formal definitions approved by the IMA in 1987.

Nowadays, deposition of the type material in a professionally curated museum is required by the Commission on New Minerals, Nomenclature and Classification of the IMA when approving a new mineral species.

Types
The following definitions for kinds of type specimens were approved in 1987 by the Commission on New Minerals and Mineral Names and the Commission on Museums of the International Mineralogical Association (IMA).  These definitions are primarily separated by the number of specimens necessary for definition of a mineral type.

Holotype
A holotype is a single specimen from which the original description of the mineral can be determined in whole. In plain English, a single object that can be used to completely define a mineral type. 

Cotype
Cotypes are multiple specimens from which quantitative, but not necessary, data are obtained for the original mineral description.  In plain English, multiple objects are necessary to define the mineral type.

Neotype
A neotype is a new specimen for the redefinition or reexamination of a mineral when the holotype or cotypes cannot be located or, upon examination, are inadequate for study.  These type specimens are valuable when a mineral species is reevaluated because the original description of a mineral may be incomplete or contain errors.  In plain English, a mineral that already possessed what was believed to be a sufficient definition, that is then subject to reexamination because of the discover of a new specimen.  In some cases, this may be because the original specimens were lost.

References

Bibliography

Mineralogy
Special Operations Craft – Riverine. 
Special Operations Craft – Riverine is a boat used by the United States Navy to perform short-range insertion and extraction of special operations forces in river and near-shore environments. It replaced the Patrol Boat, River, and the mini armored troop carrier.

Design
Designed for speed and tight turns, the SOC-R's V-shape belly allows the boat to skate along the surface, with relatively little drag on the hull. There is no hanging rudder or propeller blades to snag on submerged roots and rocks.

The SOC-R's five weapon mounts provide a 360-degree field of fire. The aft-mounted .50 cal covers the boat crew as they leave the shore after an extraction.

The SOC-R and its tractor and trailer fits aboard C-130 or larger aircraft. 

The craft can also be slung under an Army MH-47 helicopter using the MEATS system, which allows Combatant-Craft Crewmen to fast-rope from the helicopter onto the craft during insertion and climb a ladder from the boat to the helicopter during extraction.

Crew
Each SOC-R is crewed by four Special Warfare Combatant-craft Crewmen (SWCC) and can carry four more people. The craft are operated only by members of Special Boat Team 22 (SBT-22), based in Stennis, Mississippi. These river crews conduct mainly clandestine combat missions, often operating at night with little or no air support.

Image gallery

See also
 
 Small unit riverine craft
 Mark V Special Operations Craft
 Combatant Craft Medium
 Mark VI patrol boat

References

External links
 United States Marine Inc. Web site
 Behind the Scenes With a Special Ops Gunboat Crew - Popular Mechanics article - March 2009

United States Navy SEALs
Equipment of the United States Navy
Unclassified miscellaneous vessels of the United States Navy
Military boats
Patrol vessels of the United States Navy
Riverine warfare
Landing craft
Temco D-16. The Temco D-16 is a 1950s twin engine civil aircraft from the United States. It was produced by conversion of a Ryan Navion to replace its single engine with two wing-mounted engines. It is commonly known as the Twin Navion, although that name is also often applied to a later similar conversion, the Camair 480.

Background
The project began in 1951 as a requirement by Charles Daubenberger for an inexpensive replacement for the corporate Ryan Navion operated by his Dauby Equipment Company, to achieve better reliability while crossing high mountain ranges. He commissioned Roger Keeney of the Acme Aircraft Company to provide a solution, that evolved into a twin engine conversion of a Navion.

Design and development
Jack Riley Sr. built the first model with a team of four. With encouragement from Lycoming, the 125 hp Lycoming O-290 four-cylinder engine was selected for the project. Design changes from the basic Navion structure included strengthened wing spars, that supported engine mounts and other components from Piper PA-18 Super Cub, plus new engine nacelles, a faired nose section that replaced the existing engine and cowling, and a new vertical tail and rudder based on the existing horizontal stabilizer. During testing in 1952, the aircraft was initially named the X-16 Bi-Navion. On 10 November 1952, it was granted certification by the Civil Aeronautics Administration (CAA), after which it was renamed as the D-16 Twin Navion.

A second aircraft was converted for Jack Riley, who specified 140 hp engines, and he purchased the production rights from Dauby. Riley Aircraft then started production of the Riley D-16 Twin Navion, that standardized the design with 150 hp Lycoming O-320 engines and other improvements. In March 1953, after 19 conversions had been carried out, Riley subcontracted production to Temco Aircraft. Temco then purchased the sole production rights, and produced a further 46 conversions under the name Temco D-16. In September 1954, the design was upgraded to include 170 hp Lycoming O-340 engines plus increased fuel capacity in wingtip tanks, officially named Temco D-16A but typically marketed as the Riley 55 for the 1955 model year.

Operational history
In 1957, after 45 conversions to D-16A specification, production ceased in the face of competition from more cost-effective new-build types such as the Piper PA-23 Apache. Many of the D-16 models were upgraded to D-16A standards. In 2012, about 52 Temco D-16 and D-16A models remain on the US civil aircraft register, and at least three are preserved in museum collections.

Specifications (D-16)

See also

References
Notes

Bibliography
FAA Specification 2A1 Rev 5
Ogden, Bob. 2007. Aviation Museums and Collections of North America. Air-Britain 
Simpson, R. W. 1995. Airlife's General Aviation. Airlife Publishing 
Simpson, Rod. 2001. Airlife's World Aircraft. Airlife Publishing

External links

Temco aircraft
1950s United States civil utility aircraft
Low-wing aircraft
Aircraft first flown in 1952
Twin piston-engined tractor aircraft
Aircraft with retractable tricycle landing gear
Cutler Regional Airport. Cutler Regional Airport  is a public use airport located two nautical miles (4 km) west of the central business district of Cutler, a town in Washington County, Maine, United States.

Facilities and aircraft 
Cutler Regional Airport covers an area of 50 acres (20 ha) at an elevation of 55 feet (17 m) above mean sea level. It has one runway designated 9/27 with a gravel surface measuring 2,950 by 40 feet (899 x 12 m).

For the 12-month period ending August 19, 2010, the airport had 300 general aviation aircraft operations, an average of 25 per month. At that time there were 4 aircraft based at this airport: 50% single-engine, 25% multi-engine, and 25% helicopter.

See also
 List of airports in Maine

References

External links 
 Aerial image as of May 1996 from USGS The National Map
 

Airports in Maine
Airports in Washington County, Maine
Ceramic mixing technology. Ceramic mixing technology is used to mix and blend ceramics to create end products such as: ceramic powder blends, injection molding feedstock, electronics, decorative finishes, refractory linings, batteries and fuel cells, thermally conductive pastes, investment casting slurries, dental ceramics and advanced composites.

A wide range of equipment is available for these requirements.

External links
Ceramics mixing and blending technical articles

Ceramic engineering
COMPASS-2. COMPASS-2 (also known as DragSail-CubeSat) is the second satellite developed by students from FH Aachen and RWTH Aachen University. It has a sail to increase its drag coefficient, and was launched (with a number of other satellites) in 2017 by means of a Polar Satellite Launch Vehicle.

References

External links 
  FH Aachen site compass 2 

CubeSats
Student satellites
RWTH Aachen University
Satellites of Germany