omniomni/omni-engineering huggingface dataset:
Ponding. In civil engineering, ponding is the (typically) unwanted pooling of water, typically on a flat roof or roadway. Ponding water accelerates the deterioration of many materials, including seam adhesives in single-ply roof systems, steel equipment supports, and particularly roofing asphalt. On low-slope asphalt roofs, ponding water allows the oil solvent components of the asphalt to leach out and evaporate, leaving the roof membrane brittle and susceptible to cracking and leaking in the ponding location. The time taken for water to saturate a zone, usually from rainfall, causing a pond to form, is referred to as the "ponding time".

Cause
Most flat roof systems (properly called "low-slope roof systems") are designed with a slight pitch to shed water off the sides, usually into gutters, scuppers, internal drains, or a combination of these. When a scupper or drain is clogged or fails for other reasons, storm water tends to pool around that low area.  Over time, with each passing storm, the weight of the storm water will deflect the structural system beyond the structure's bending point, thus allowing a bigger puddle to form.  As a bigger puddle forms more weight is applied to the structural system causing more bending, allowing an even bigger puddle, then more weight, until the structure fails.

Construction codes
In the construction industry, the National Roofing Contractors Association (NRCA) defines roof ponding as "water that remains on a roof surface longer than 48 hours after the termination of the most recent rain event".

According to the 2009 International Building Code Chapter 15 "Roof Assemblies and Roof Top Structures" & Chapter 16 "Structural Design"; 
When scuppers are used for secondary (emergency overflow) roof drainage, the quantity, size, location and inlet elevation of the scuppers shall be sized to prevent the depth of ponding water from exceeding that for which the roof was designed ... Ponding instability. For roofs with a slope less than 1/4 inch per foot [1.19 degrees (0.0208 rad)], the design calculations shall include verification of adequate stiffness to preclude progressive deflection in accordance with Section 8.4 of ASCE 7.

Ponding on land
When water is diverted into a lower area that has no outlet or is not suitable for drainage, water will begin to pool, and over time the weight of the water will create a deeper pool, allowing more water to sit, eventually creating a permanent water feature.  Some municipalities recognize this as an issue on private land, such as the City of Indianapolis.

A municipality in New Zealand has noted that "groundwater ponding is a chronic problem, that results in damp housing and waterlogged sections. The damage that it causes is less apparent than the damaging events associated with floods, but the duration of groundwater ponding, which can last for several months, makes it a serious issue for those affected".

Ponding that forms on paved surfaces, like streets or parking lots that are not properly pitched, will cause issues such as deep puddles and crocodile cracking.

See also
 Horton overland flow
 Stabilization pond

References

Construction
AeroLites AeroSkiff. The Aerolites AeroSkiff is an American two-seat ultralight amphibian built by Aerolites Inc. The aircraft is sold either completed or as a kit for home builders.

Design and development
The Aeroskiff is a braced high-wing monoplane powered by a Rotax 582 driving a pusher propeller. It has an open cockpit for a pilot and passenger and a retractable landing gear for land or sea operation.

The aircraft is too heavy for the Fédération Aéronautique Internationale microlight rules. Despite its repositionable landing gear, it can fit into the US light-sport aircraft classification since it is intended for operation on water.

Operational history
By 1998 the company had reported that two examples were flying.

Specifications

See also

References

Notes

External links

AeroSkiff
1990s United States civil utility aircraft
Amphibious aircraft
Single-engined pusher aircraft
High-wing aircraft
Homebuilt aircraft
Flying boats
Aircraft first flown in 1995
PS-algol. PS-algol is an orthogonally persistent programming language.

PS-algol was an extension of the language S-algol implemented by the University of St Andrews and the University of Edinburgh, Scotland. S-algol was designed by Ron Morrison and extended by Pete Bailey, Fred Brown, Paul Cockshott, Ken Chisholm, and Al Dearle. These extensions were additional standard functions that provide a persistent heap that survives termination of PS-algol programs.

PS-algol was the world's first fully implemented persistent programming language, and had many users both in academia and, notably, in International Computers Limited (ICL) research labs.

History 

PS-algol was conceived by chance, when Ron Morrison was on sabbatical at the University of Edinburgh and met Malcolm Atkinson. Atkinson had been experimenting with persistent programming languages and was struggling to find a coherent model for a persistent Pascal variant. Morrison, whose interest in general-purpose programming had led to the development of S-algol, a general purpose teaching language, realised that S-algol's type system would more easily allow adding orthogonal persistence.

See also 
Flex machine

References 

Algol programming language family
History of computing in the United Kingdom
Xenon dioxide. Xenon dioxide, or xenon(IV) oxide, is a compound of xenon and oxygen with formula XeO2 which was  synthesized in 2011. It is synthesized at 0 °C by hydrolysis of xenon tetrafluoride in aqueous sulfuric acid:

Structure

 has an extended (chain or network) structure in which xenon and oxygen have coordination numbers of four and two respectively. The geometry at xenon is square planar, consistent with VSEPR theory for four ligands and two lone pairs (or AX4E2 in the notation of VSEPR theory).  

The XeO2 network does not share a crystal structure of SiO2 (which has tetrahedral coordination at Si), but XeO2 units are believed to intermix with SiO2 in Earth's mantle.  Computational studies suggest that xenon cannot displace silicon directly, but can fill pre-existing silicon vacancies.  The stability of the resulting material under standard conditions depends on its allotrope.  Patterned off quartz, it likely decomposes; but materials patterned off fibrous silica may be metastable.    

In addition, the existence of an XeO2 molecule was predicted by an ab initio quantum chemistry method several years earlier by Pyykkö and Tamm, but these authors did not consider an extended structure.

Properties

 is a yellow-orange solid. It is an unstable compound, with a half-life of about two minutes, disproportionating into  and xenon gas. Its structure and identity was confirmed by cooling it to −150 °C so that Raman spectroscopy could be performed before it decomposed.

At -78 °C, the majority of XeO2 decomposed over a period of 72 hours, which was identified by the fading of the original yellow product to a pale yellow. Almost all yellow color indicating pure XeO2 disappeared over the span of 1 week.

3 XeO2 → Xe + 2 XeO3

References

Oxides
Xenon(IV) compounds
Inorganic compounds
Substances discovered in the 2010s
Robotium. Robotium is an open-source test framework for writing automatic gray box testing cases for Android applications. With the support of Robotium, test case developers can write function, system and acceptance test scenarios, spanning multiple Android activities. Robotium can be used both for testing applications where the source code is available and applications where only the APK file is available and the implementation details are not known.

The framework is released under Apache License 2.0. Its founder and main developer is Renas Reda. Version 5.0.1 was released on January 5, 2014.

Robotium is similar to Selenium, but for Android. It has support for Android features such as activities, toasts, menus and context menus.

See also
 Android (operating system)
 Selenium (software)
 List of Android devices
 List of Android OS-related topics

References

External links
 Robotium Framework website
 Robotium Recorder website

Android (operating system) development software
Jind Institute of Engineering and Technology. Jind Institute of Engineering and Technology is an institute of higher education in Jind, Haryana, India. It is situated on Jind-Panipat Road. It was established in 1998 and is affiliated to Kurukshetra University, Kurukshetra for all academic purposes. The college offers different engineering programs like Computer Science and Engineering, Mechanical Engineering, Electronics and Communication Engineering, Electrical Engineering and Civil Engineering.

See also
 Kurukshetra University
 List of Engineering Colleges affiliated to Kurukshetra University, Kurukshetra
 Education Maximum School of Engineering and Applied Research
 List of Colleges affiliated to Kurukshetra University, Kurukshetra

References

Educational institutions established in 1998
Engineering colleges in Haryana
1998 establishments in Haryana
Kurukshetra University
Jind
Agusta GA.40. The Agusta GA.40 was a 2-cylinder, air-cooled, horizontally opposed engine developed in Italy by Agusta for light aircraft use. It was intended for use in motorgliders. The engine was produced in the 1950s and 1960s.

Specifications

Applications
Corby Starlet
Kokkola Ko-04

Notes

References

1950s aircraft piston engines
Boxer engines
Agusta aircraft engines
Indian Institute of Aeronautics. Indian Institute Of Aeronautics (IIA) is one of the oldest aircraft maintenance training institutes in New Delhi, India. It was founded by avid aviator Captain Ram Niwas Sinha in 1982. In 1983 IIA earned approval from the Director General of Civil Aviation (DGCA), Govt. of India. IIA was transferred to Mundka, New Delhi from its initial approved base of Patna Airport in the year 2001. IIA is active in the field of Aircraft Maintenance Training through generations of trained technical manpower for the Airlines / Aviation Industry.

The organization forfeited its DGCA approval in year 2013 and applied went for European Union Aviation Safety Agency (EASA) Basic Aircraft Maintenance Training Approval in the year 2015. It earned permission to run EASA Part-66 aircraft maintenance training program in Category B1.1 Aeroplane Turbine.

Curriculum activities and AME Training Programme framed keeping in view the current technology in force in Aircraft Maintenance Engineering, are approved by European Union Aviation Safety Agency. Infrastructure and Training facilities of Indian Institute of Aeronautics  comply with EASA requirements.

IIA together with JRN Institute of Aviation Technology in New Delhi and Bharat Institute of Aeronautics at Patna formed the IIA Group of Institutions, which are operative under the same management under certification of DGCA and EASA approved aircraft maintenance training courses. The training standards followed and practiced by IIA Group are equivalent to International Civil Aviation Organization (ICAO type-II). IIA Group also hold training with examination privileges for EASA Part-66 aircraft maintenance license.

References

External links 

 www.iiagroup.co.in
 Dgca Approved AME Colleges
 Top AME college in India
 EASA Approved organisations in India
 ACT for Academy, Airbus Aircraft

Aeronautics organizations
Aviation in India
Education in Delhi
Vocational education in India
Aviation organisations based in India
Davies and Metcalfe. Davies and Metcalfe Ltd is a railway equipment and locomotive manufacturer from Romiley, Manchester, England. It was founded in Aberystwyth in 1878. The company is now owned and run by Richard Charles Metcalfe and they continue to manufacture steam locomotive and traction engine parts from original drawings, as well as modern railway parts worldwide.

History

Rheidol Foundry
James Metcalfe (1847–1920) was apprenticed to Sharp Stewart and worked for the company until 1867 before joining the Manchester and Milford Railway at Aberystwyth as locomotive foreman. Between 1875 and 1877 he took out three patents for an improved exhaust steam injector for steam locomotives and developed it with the financial support of David Davies "Llandinam" and Edward Hamer, the General Manager of the Manchester & Milford Railway. The Patent Exhaust Steam Injector Company was established at the Rheidol Foundry, Aberystwyth in April 1878.

Davies and Metcalfe
The company later moved to Romiley in the Metropolitan Borough of Stockport, Greater Manchester and changed its name to Davies and Metcalfe. It produced a range of locomotive engineering products including lubricators, exhaust steam injectors, vacuum brake ejectors etc. They also manufacture the pneumatic disc brake systems used on modern trains including the V/Line Sprinter and British Rail Class 56.

Locomotives

The company built two  locomotives for the  gauge Vale of Rheidol Railway at Aberystwyth in 1902. They also renovated two locomotives for the North Wales Narrow Gauge Railway in 1902 (Snowdon Ranger) and 1903 Moel Tryfan).

Metcalfe-Oerlikon
Davies and Metcalfe had an arrangement with Oerlikon and sold railway air brake equipment under the name Metcalfe-Oerlikon. This was fitted to some British Railways diesel locomotives, e.g., Classes 45 and 46.

Notes

References
Richard Metcalfe. Davies & Metcalfe Ltd: railway engineers to the world. 1999. 208 pp. 142 illus.

Locomotive manufacturers of the United Kingdom
Companies established in 1878
Explorer PG-1 Aqua Glider. The Explorer PG-1 Aqua Glider is an American single seat, biplane glider that was designed by Bill Skiliar in 1959 and made available as plans for amateur construction. The prototype was built with help from a troop of Air Explorer Scouts that same year.

Design and development
Skiliar was a Colonel in the USAF and an aeronautical engineer and test pilot. He designed the Aqua Glider to be towed behind a boat, taking off from the water, releasing the tow rope and then gliding to a landing on the water.

The Aqua Glider is made from wood and covered with doped aircraft fabric. The landing gear is fixed and consists of a pair of water skis. The aircraft uses spoilers instead of ailerons for roll control and features an all-flying tail and a trim system. The biplane wing employs a NACA 4412 airfoil.

The aircraft is towed behind a ski tow boat, lifting off at  and climbing to about , depending on the length of the tow rope used. The aircraft does not stall, but enters a nose-high mushing condition with a slow rate of descent.

Plans were sold for US$25 by Corben Development Corporation of Venice, Florida and completed aircraft cost about US$800 in materials in 1983.

Skiliar made several modifications to the design, experimenting with landing gear for land use made from automobile leaf springs. He also created a powered version with two McCulloch MC-70 go-cart engines mounted in the aft fuselage behind the wing spar, with the propeller above the engines on a streamlined pylon that housed the drive chains. The powered version was not successful and was returned to glider configuration.

Operational history
By 1983 the prototype had flown over a thousand flights and plans had been widely sold in the United States and many other countries.

Aircraft on display
EAA AirVenture Museum – the prototype was donated to the museum in 1970

Specifications (variant specified)

See also

References

1950s United States sailplanes
Aircraft first flown in 1959
Biplanes
Flying boats
George Galloway (parachute maker). George Galloway (born 17 November 1949) is an American businessman who is the founder, president and CEO of Precision Aerodynamics, Inc. He is known for creating and distributing the "Raven" series of ram-air parachutes, the first type that could be scaled to different sizes, allowing people of different body types and weights to experience the same performance from the same type of parachute. Raven reserve parachutes are the most widely used reserve canopies in the world, used by the U.S. military for special operations. Galloway entered the parachute business since 1975 selling to clients ranging from both U.S. and foreign armed forces to high-rise building workers in dangerous areas and in 21 different countries.

References

External links 
Precision Aerodynamics Official Website 
Parachute Industry Association Official Website
United States Parachute Administration Official Website

1949 births
Living people
American aviation businesspeople
Businesspeople from Chattanooga, Tennessee
Critical Zone Observatories. Critical Zone Observatories (CZO) is an interdisciplinary collaborative research project across nine institutions with the purpose of understanding the chemical, physical, geological, and biological processes that both shape the surface of Earth and support terrestrial life. Active CZO sites include locations in Boulder Creek, Calhoun, Eel River, Intensively Managed Landscapes (IML), Jemez River Basin & Santa Catalina Mountains, Luquillo, Reynolds Creek, Susquehanna Shale Hills, and Southern Sierra.

Funded by the National Science Foundation, CZO has been working since its 2007 inception to critically engage the scientific community and increase understanding of the importance of Critical Zone science.

Mission 
To use its institutions together to create a unique network that fosters scientific inquiry and discovery with regards to Earth's Critical Zone. Much like the interconnectedness of Earth's critical zone systems, CZO relies upon a range of disciplines, including geosciences, hydrology, microbiology, ecology, soil science, and engineering, to develop a theoretical spatial-temporal framework for critical zone evolution for both quantifiable and conceptualized data analyses.

Education and outreach 
Through research and education opportunities associated with each CZO, cross-CZO scientific endeavors, and annual meetings, CZO uses a variety of interfaces to communicate Critical Zone science to students and teachers.

NSF-funded Critical Zone Observatories

National Office 
In 2014, a National Office branch was formalized to facilitate communication and collaboration among researchers and students, support education and outreach initiatives, coordinate data protocols and common measurements, and to provide a single point of contact for the Critical Zone Observatories.

Critical Zone Observatories worldwide 
There are 46 Critical Zone Observatories globally, with the majority in North America and Europe. There are 17 CZOs in Europe, 5 in Southeast Asia, 3 near Australia, 2 CZOs in Africa, and 2 in South America.

See also 
 Earth's critical zone

References

External links 
 Critical Zone Network
 Critical Zone Exploration Network

Environmental research institutes
Advanced Energy Materials. Advanced Energy Materials is a peer-reviewed scientific journal covering energy-related research, including photovoltaics, batteries, supercapacitors, fuel cells, hydrogen technologies, thermoelectrics, photocatalysis, solar power technologies, magnetic refrigeration, and piezoelectric materials. It publishes invited reviews and progress reports, full papers, and rapid communications. Established in 2011, Adv. Energy Mater. began as a monthly journal in 2012 and switched to 18/year in 2014, biweekly in 2016, 36/year in 2018, and weekly in 2019.

Abstracting and indexing 
The journal is abstracted and indexed in:
 Chemistry Citation Index 
 Current Contents/Engineering, Computing & Technology 
 Current Contents/Physical, Chemical & Earth Sciences 
 ENERGY
 Inspec
 Materials Science Citation Index
 Science Citation Index Expanded

References

External links
 

Energy and fuel journals
English-language journals
Materials science journals
Academic journals established in 2011
Monthly journals
Wiley-Blackwell academic journals
Energy research
Officine Meccaniche Giovanni Cerutti. Officine Meccaniche Giovanni Cerutti S.p.A. is an Italian joint-stock company headquartered in Casale Monferrato, which designs and manufactures rotogravure and flexo printing presses and related equipment for magazine and newspaper production, and for the printing and converting of packaging materials.

See also 

List of Italian companies

Notes

External links
 
 ‘Officine meccaniche Giovanni Cerutti’, ACIGMA (Associazione Costruttori Italiani Macchine per l'industria Grafica, Cartotecnica, Cartaria, di Trasformazione e Affini / Italian Manufacturers Association of Machinery for the Graphic, Converting and Paper Industry).

Industrial machine manufacturers
Engineering companies of Italy
Companies based in Casale Monferrato
Manufacturing companies established in 1920
Italian companies established in 1920
Italian brands
Pulp Mill Covered Bridge. The Pulp Mill Covered Bridge, also called the Paper Mill Covered Bridge, is a wooden covered bridge that crosses Otter Creek between Middlebury and Weybridge, Vermont on Seymour Street. It was listed on the National Register of Historic Places in 1974.

History
The bridge is of Burr arch design. Around 1860, the original Burr arches were removed, and laminated ones added to King post trusses, changing the bridge type to a King post with Burr arch design. This bridge has many distinctions. It is one of only seven double-barreled (two lane) covered bridges in the country, one of only two in the State of Vermont (the Museum Covered Bridge being the other), and the only still carrying regular traffic. It is also the oldest covered bridge in Vermont, and one of the oldest in the country.

The exact age of the bridge is in question. A sign on the bridge states it was built between 1808 and 1820. Covered Bridge expert Jan Lewandosky has placed the year of construction at approximately 1850 based on his search of Minutes of the Selectboard of the Town of Middlebury, and his voluminous knowledge of covered bridge construction. In 1850 the Town of Middlebury sent a person to Essex, Vermont, to examine a recently completed Burr Arch bridge, unfortunately the design was not copied correctly leading to the design flaws.

Improvements
The bridge was originally built as a single span but inherent design problems, and heavy use, has driven almost constant improvements. Amongst those improvements was the addition of two piers in the creek effectively dividing the bridge into 3 spans. A non-structural improvement was the addition of a walkway on the outside of the bridge by the Towns of Weybridge and Middlebury. Several other rounds of repairs have been made and chronicled extensively at the Vermont Bridges website.

The Pulp Mill bridge was closed from January 2, 2012 until November 9, 2012 for rehabilitation.

Photo gallery

See also
List of Vermont covered bridges
List of bridges documented by the Historic American Engineering Record in Vermont
List of bridges on the National Register of Historic Places in Vermont
National Register of Historic Places listings in Addison County, Vermont

References

External links

Buildings and structures in Middlebury, Vermont
Buildings and structures in Weybridge, Vermont
Bridges completed in 1820
Covered bridges on the National Register of Historic Places in Vermont
King post truss bridges in the United States
Wooden bridges in Vermont
Bridges in Addison County, Vermont
Tourist attractions in Addison County, Vermont
Historic American Engineering Record in Vermont
National Register of Historic Places in Addison County, Vermont
Road bridges on the National Register of Historic Places in Vermont
Burr Truss bridges in the United States
1820 establishments in Vermont