omniomni/omni-engineering huggingface dataset:
Gain scheduling. In control theory, gain scheduling is an approach to control of nonlinear systems that uses a family of linear controllers, each of which provides satisfactory control for a different operating point of the system.

One or more observable variables, called the scheduling variables, are used to determine what operating region the system is currently in and to enable the appropriate linear controller.  For example, in an aircraft flight control system, the altitude and Mach number might be the scheduling variables, with different linear controller parameters available (and automatically plugged into the controller) for various combinations of these two variables. In brief, gain scheduling is a control design approach that constructs a nonlinear controller for a nonlinear plant by patching together a collection of linear controllers.

A relatively large scope state of the art about gain scheduling has been published in (Survey of Gain-Scheduling Analysis & Design, D.J.Leith, WE.Leithead).

Recently, new methodologies using Machine learning, such as Adaptive control based on Artificial Neural Networks (ANN) and Reinforcement Learning, have been studied.

See also 
Linear parameter-varying control

References

Further reading

 

Nonlinear control
Control engineering
Classical control theory
O-Ethyl methylphosphonothioic acid. O-Ethyl methylphosphonothioic acid (EMPTA) is an organophosphate compound. A dual-use chemical, it has constructive uses in the synthesis of pesticides and pharmaceuticals, and it is also a precursor in the synthesis of nerve agents such as Agent VM and Agent VX. The detection of EMPTA is cited as a major influence in the United States' 1998 decision to destroy the Al-Shifa pharmaceutical factory in Sudan.

References

Phosphonothioates
Ethyl esters
Site license. A site license is a type of software license that allows the user to install a software package in several computers simultaneously, such as at a particular site (facility) or across a corporation. Depending on the amount of fees paid, the license may be unlimited or may limit simultaneous access to a certain number of users. The latter is called a concurrent site license.

Overview
The term "site" may not necessarily refer to a physical site or geographic location. It is simply defines a limitation on the user's access rights. The usage of the term dates back to 1950s, when mainframes limited to a specific sites were being used. Nowadays, these types of licenses are rare, but still used in some sectors like manufacturing. Vendors may insert clauses that would allow representatives to visit the site and verify that the software usage conforms to the license. 

Site licenses are sometimes called multiseat licenses in implied distinction from individual (single-seat) licenses; this usage parallels the terminology of multiseat configurations for mainframes, with the same figurative analogy of multiple workers each seated in front of an instance (one terminal or one copy of the application). The cost of the license can then be analyzed in terms of cost per installed seat, with the idea being that such cost must be lower if site licensing is to be advantageous over individual licensing.

Another aspect, aside from cost, is convenience. Some software vendors had one-floppy per computer restrictions, which the New York Times described as "the equivalent of a book publisher insisting that no two people could use the same book, even at different times." A different inconvenience was copy protection, which was deprecated as crippleware.

Customization
Customizations, subset, restricted and specialized licensing arrangements are among those arrangements that are beyond individual single-copy licenses. One such pricing, for a customized "site licensing" refers to deals made by large institutions, like universities, with software firms so that affiliated persons can buy the software at discounted prices. Web-only is another customization, particularly when the alternative is paper-based.

See also
 Shelfware

References

Software licensing
Terms of service
Sharpless oxyamination. The Sharpless oxyamination (often known as Sharpless aminohydroxylation) is the chemical reaction that converts an alkene to a vicinal amino alcohol.  The reaction is related to the Sharpless dihydroxylation, which converts alkenes to vicinal diols. Vicinal amino-alcohols are important products in organic synthesis and recurring pharmacophores in drug discovery.

Mechanism
Akin to the dihydroxylation, the oxyamination involves the cycloaddition of the alkene to an imido Os(VIII) intermediate of the type OsO3(NR).  Such species are generated by treatment of osmium tetroxide with the sodium chloramines.  Typical procedures combine chloramine-T, alkene, an osmium catalyst, and a chiral ligand. Related procedures use benzyl carbamate (CbzNH2), sodium hydroxide, tert-butyl hypochlorite to give CbzNCl(Na).
R2NH + t-BuOCl → R2NCl + t-BuOH

Further reading
Early papers in the development of this methodology.
Sharpless, K. B.; Patrick, D. W.; Truesdale, L. K.; Biller, S. A. J. Am. Chem. Soc. 1975, 97, 2305. ()
Herranz, E.; Biller, S. A.; Sharpless, K. B. J. Am. Chem. Soc. 1978, 100, 3596-3598. ()
Bäckvall, J. E.; Oshima, K.; Palermo, R. E.; Sharpless, K. B. J. Org. Chem. 1979, 44, 1953. ()

References

Organic redox reactions
Name reactions
Walkalong glider. A walkalong glider is a lightweight, slow-flying model aircraft designed to be kept aloft by controllable slope soaring in the rising air generated by the pilot who walks along with the glider as it flies, usually holding a paddle. Hands or even the forehead can also be used to create an updraft. This type of soaring differs from other types of slope soaring in that the orographic lift (or "hill") is following the plane as it flies in the air and thus no other wind is required.

Types of walkalong gliders have been patented. Some walkalong glider designs have been named, such as the air surfer, the windrider, the tumblewing and the follow foil.

Walkalong gliding has also been referred to as controllable slope soaring but should not be confused with dynamic soaring.

Ground effect should not be confused with ridge lift when explaining how walkalong gliders stay up. Ground effect involves a horizontal surface. Ridge lift requires a sloping surface. In ground effect the air does not have to move relative to the ground whereas ridge lift requires the wind to be blowing horizontally against the ridge. Walkalong gliders are sustained and controlled in the ridge lift produced by the moving paddle.

History 
The first description of a walkalong glider appears in the 1955 patent of J. E. Grant. The first flight of a functional walkalong glider appears briefly in the Academy Award winning documentary The Flight of the Gossamer Condor.

Walkalong glider design
A walkalong glider must fly at or below walking speed. Light weight materials and specific design will reduce a walkalong glider's flying speed. For example, using a lower paper density will reduce a paper walkalong glider's wing loading and thus its air speed. Walkalong glider designs have differing wing loadings, for example, the tumblewing type designs will have lower wing loading than traditional nose weighted paper airplane designs made from the same paper density. For nose weighted walkalong glider designs, the wings should include a twist or washout to improve roll control close to stall speed. Although many walkalong gliders are flying wing designs (as are almost all flying and gliding animals) walkalong glider designs based on traditional fixed-wing aircraft (incorporating an empennage or tail) have been made from balsa wood sticks and tissue paper.

The paddle should be made from a sheet of light weight but rigid material such as corrugated cardboard or foamcore. The larger the area of the sheet the stronger the updraft created at the top edge. A 1-meter square area paddle is large enough to fly most walkalong gliders.

See also 
 Gliding
 Orographic lift
 Slope soaring
 controllable slope soaring
 Human-powered aircraft

External links

 Method of Flying Toy Airplane and Means Therefor
 How to build a walkalong glider
 Sliced Foam Walkalong Glider Development from sciencetoymaker.org
 PBS Scientific American Frontiers Free Flight episode with Walkalong Glider

References 

Gliding technology
Model aircraft
Chloryl fluoride. Chloryl fluoride is the chemical compound with the formula ClO2F. It is commonly encountered as side-product in reactions of chlorine fluorides with oxygen sources. It is the acyl fluoride of chloric acid.

Preparation
ClO2F was first reported by Schmitz and Schumacher in 1942, who prepared it by the fluorination of ClO2. The compound is more conveniently prepared by reaction of sodium chlorate and chlorine trifluoride and purified by vacuum fractionation, i.e. selectively condensing this species separately from other products. This species is a gas boiling at −6 °C:
6 NaClO3 + 4 ClF3 → 6 ClO2F + 2 Cl2 + 3 O2 + 6 NaF

Structure
In contrast to O2F2, ClO2F is a pyramidal molecule. This structure is predicted by VSEPR. The differing structures reflects the greater tendency of chlorine to exist in positive oxidation states with oxygen and fluorine ligands. The related Cl-O-F compound perchloryl fluoride, ClO3F, is tetrahedral.
The related bromine compound bromyl fluoride (BrO2F) adopts the same structure as ClO2F, whereas iodyl fluoride (IO2F) forms a polymeric substance under standard conditions.

References

External links
 WebBook page for ClO2F

Chloryl compounds
Oxyfluorides
Nonmetal halides
Gases
Substances discovered in the 1940s
List of Historic Mechanical Engineering Landmarks. 
The following is a list of Historic Mechanical Engineering Landmarks as designated by the American Society of Mechanical Engineers (ASME) since it began the program in 1971. The designation is granted to existing artifacts or systems representing significant mechanical engineering technology. Mechanical Engineering Heritage Sites are particular locales at which some event or development occurred or which some machine, building, or complex of significance occupied. Also Mechanical Engineering Heritage Collections refers to a museum or collection that includes related objects of special significance to, but not necessarily a major evolutionary step in, the historical development of mechanical engineering.

Clicking the landmark number in the first column will take you to the ASME page on the site where you will also find the downloadable brochure from the dedication.

There are over 275 landmarks on the list.

See also 
 American Society of Mechanical Engineers (ASME)
 Institution of Mechanical Engineers
 List of Historic Civil Engineering Landmarks
 Mechanical Engineering Heritage (Japan)

References

External links
 
 American Society of Mechanical Engineers Landmarks

American Society of Mechanical Engineers
 
Historic Mechanical Engineering Landmarks
Mechanical Engineering Landmarks
Indian locomotive class WAG-7. The Indian locomotive class WAG-7 is a class of 25 kV AC electric locomotives that was developed in 1990 by Chittaranjan Locomotive Works for Indian Railways. The model name stands for broad gauge (W), alternating current (A), goods traffic (G) engine, 7th generation (7). They entered service in 1992. A total of 1974 WAG-7 were built at CLW and BHEL between 1990 and 2015 by CLW and 2009 and 2023 by BHEL which made them the most numerous class of mainline electric locomotive till its successor the WAG-9.

The WAG-7 is one of the most successful locomotives of Indian Railways, serving freight trains since its introduction in 1990. Even though with the advent of new 3-phase locomotives like WAG-9 and WAG-12, all WAG-7 locomotives except ones destroyed in accidents, are in service and doing all types of duties.

History 
The history of WAG-7 begins in the early 1990s with the aim of addressing the shortcomings of the previous WAG-5  class and remove steam locomotives from IR by a target date of 1990. The WAG-5 though were great successes, had become underpowered to meet the growing demands of the Indian Railways. So in early 1990s IR decided to look for a successor the WAG-5 class. The required specification was of a 5000 horsepower locomotive.

Initially, the Indian railways invited tenders to build locomotives to the new specification. The following responses were received:

 CLW submitted their upgraded WAG-5 model with 5000 hp with Co-Co bogies.
 BHEL submitted a 5000 hp locomotive with thyristors control and Co-Co bogies.

Each company submitted their prototypes and Indian Railways designated these prototypes as the WAG-7 class and WAG-8 class respectively. Technologically thyristor controlled BHEL WAG-8 was meant to be superior to the WAG-7 which was effectively using tap-changer technology from the 1960s. But due to issues from WAG-8, WAG-7 was selected for mass production.

However, even before the WAG-7 another type of electric locomotive was imported from ASEA in 1988. This locomotive was classified as WAG-6A. However WAG-6As were not selected for mass production because emergence of 3 Phase AC locomotives.

Locomotive sheds

• Key : 
M -> WAG-7M (Formerly known as WCAM-3)

See also

Indian Railways
Locomotives of India
Rail transport in India

References

External links

Specifications
India railway fan club

Electric locomotives of India
25 kV AC locomotives
Co-Co locomotives
5 ft 6 in gauge locomotives
Railway locomotives introduced in 1992
BHEL locomotives
Chittaranjan Locomotive Works locomotives
Indian locomotive class WAG-5. The Indian locomotive class WAG-5 is a class of 25 kV AC electric locomotives that was developed in 1978 by Chittaranjan Locomotive Works for Indian Railways. The model name stands for broad gauge (W), alternating current (A), goods traffic (G) engine, 5th generation (5). They entered service in 1980. A total of 1196 WAG-5 were built at CLW and BHEL between 1978 and 1998, which made them the most numerous class of mainline electric locomotive until  the introduction of its successor, the WAG-7.

The WAG-5 is one of the most successful locomotives of Indian Railways currently serving both freight and passenger trains for over  43 years. This class provided the basic design for a number of other locomotives, like WAG-7 and the WCM-6. However, with the advent of new 3-phase locomotives like WAG-9 and WAG-12, the WAG-5 locomotives were relegated to hauling smaller passenger trains and now the aging fleet the WAG-5 locomotives are rapidly being withdrawn from mainline duties and scrapped.

History 

WAG-5A is the one with Alstom traction motors. WAG-5B is a converted WAM-4. WAG-5H(x) is with Hitachi traction motors. WAG-5P(x) is a passenger dedicated class. WAG-5(x)D are fitted with dual brakes and WAG-5(x)E are fitted with air brakes. WAG-5RH and WAG-5HR are fitted with Rheostatic or Friction braking. Another variant is WAG-5HG. The units with additional '6P' markings have all parallel grouped traction motors. WAG-5HB is built by BHEL. Some units are fitted with Static Converter (STC), Microprocessor, Dynamic brake resistors (DBR) and SI unit. Due to the advent of WAG-7 and WAG-9, these locos except WAG-5HA/HB are even used for passenger trains although it is a freight-dedicated locomotive. WAG-5HB is homed at Jhansi shed near BHEL's installations for maintenance purposes. WAG-5 has a shell of the WAM-4. Units numbered till 23293 have side louvre and round glass windows like the WAM-4 and units after 23293 have WAG-7 style of Louvre for better ventilation. Recently, WAG-5 have been fitted with data loggers. Unit numbered 23026 was selected by RDSO for adoption of thyristor controlled electricals in 1995. This was done due to the loss of suppliers of tap changer control. Project began in 1992. The new prototype system built in collaboration with Bhabha Atomic Research Centre was fitted in the locomotive between 1997 and 1998. However, due to several problems like interference with signalling equipment, the project was ceased in 1999. The engine was rebuilt to original WAG-5 and designated as WAG-5P.

Technical specification

Locomotive sheds

See also
Locomotives of India
Rail transport in India

References

External links

http://www.irfca.org/faq/faq-specs.html#WAG-5
Electric locomotives in India
India railway fan club

Electric locomotives of India
25 kV AC locomotives
Co-Co locomotives
Railway locomotives introduced in 1978
5 ft 6 in gauge locomotives
Adapted process. In the study of stochastic processes, a stochastic process is adapted (also referred to as a non-anticipating or non-anticipative process) if information about the value of the process at a given time is available at that same time. An informal interpretation is that X is adapted if and only if, for every realisation and every n, Xn is known at time n. The concept of an adapted process is essential, for instance, in the definition of the Itō integral, which only makes sense if the integrand is an adapted process.

Definition
Let
  be a probability space;
  be an index set with a total order  (often,  is , ,  or );
  be a filtration of the sigma algebra ;
  be a measurable space, the state space;
  be a stochastic process.

The stochastic process  is said to be adapted to the filtration  if the random variable  is a -measurable function for each .

Examples
Consider a stochastic process X : [0, T] × Ω → R, and equip the real line R with its usual Borel sigma algebra generated by the open sets.

 If we take the natural filtration F•X, where FtX is the σ-algebra generated by the pre-images  for Borel subsets B of R and times 0 ≤ s ≤ t, then X is automatically F•X-adapted. Intuitively, the natural filtration F•X contains "total information" about the behaviour of X up to time t.
 This offers a simple example of a non-adapted process : set Ft to be the trivial σ-algebra {∅, Ω} for times 0 ≤ t < 1, and Ft = FtX for times . Since the only way that a function can be measurable with respect to the trivial σ-algebra is to be constant, any process X that is non-constant on [0, 1] will fail to be F•-adapted. The non-constant nature of such a process "uses information" from the more refined "future" σ-algebras Ft, .

See also
 Predictable process
 Progressively measurable process

References

Stochastic processes
Ebonol (material). Ebonol is a synthetic material whose name derives from its similarity in appearance, hardness, and stability to ebony wood. Ebonol is used as a substitute for ebony in the construction of stringed and woodwind instruments (specifically clarinets). The material is particularly well suited for the fingerboards of fretless bass.

Ebonol is technically known as "XXX Paper Phenolic" and is a high-pressure laminate made from layers of black paper and phenolic resin.

See also 

 Richlite
 Micarta

Composite materials
Lutherie
Toreva block. A Toreva block landslide is a distinctive landslide type which may occur when a stronger material such as sandstone or limestone overlies a weaker material such as shale and an eroding agent undercuts the weaker lower layer.  The type was first recognized by Parry Reiche in 1937, and takes its name from Toreva, Arizona.  Toreva blocks exhibit a characteristic backward rotation toward the parent cliff.

The existence of Toreva blocks may be used to infer a warmer or wetter earlier climate, e.g. toreva blocks in the Transantarctic Mountains.

References

External links 
Toreva, AZ Landsliding
Toreva blocks in the Transantarctic Mountains: implications for Cenozoic paleoclimate

Geomorphology
Geological processes
Landslides
Reber Plan. The Reber Plan was a late 1940s plan to fill in parts of the San Francisco Bay. It was designed and advocated by John Reber—an actor and theatrical producer.

San Francisco Bay Project
Under the plan, which was also known as the San Francisco Bay Project, the mouth of the Sacramento River (from Suisun Bay) would be channelized by dams and would feed two vast freshwater lakes within the bay, providing drinking and irrigation water to the residents and farmers of the Bay Area. The barriers would support rail and highway traffic and would create the two freshwater lakes. Between the lakes, Reber proposed the reclamation of  of land that would be crossed by a freshwater channel. West of the channel would be airports, a naval base, and a pair of locks comparable in size to those of the Panama Canal. Industrial plants would be developed on the east.

The San Francisco Chronicle endorsed the plan's concept of a causeway to replace or supplement the San Francisco Bay Bridge, stating:

Feasibility tested
In 1946, the Alameda County Committee for a Second Bay Crossing and noted civil engineer Glenn B. Woodruff estimated the plan would cost $2.5 billion, more than 10 times Reber's estimate. Woodruff, who had helped design the San Francisco-Oakland Bay Bridge, blamed a misunderstanding of the geology of the bay for the massive discrepancy. 

In 1953 the U.S. Army Corps of Engineers recommended more detailed study of the plan and eventually constructed a hydraulic model of the Bay Area to test it. The barriers, which were the plan's essential element, failed to survive this critical study. The scrapping of the Reber Plan in the early 1960s was one sign, perhaps, of the end of an era of grandiose civil works projects aimed at totally restructuring a region's natural environment, and the birth of the environmental era.

See also 
Atlantropa
Salt Water Barrier (Delaware River)

References

External links
 
 

History of the San Francisco Bay Area
San Francisco Bay
Volkswagen Group D platform. The Volkswagen Group D platform is a series of automobile platforms from the German concern Volkswagen Group.  It has been used for large luxury automobiles.  Originally used by the Audi marque, it is also latterly used by the Volkswagen Passenger Cars, and Bentley marques.

D1/D11
The D1 (also known as the D11) platform was based on a stretched version of the Volkswagen Group C3/C4 platform:
Audi V8 (Typ 44) (1988–1991)
Audi V8 (Typ 4C) (1991–1994)

D2
The D2 platform is an all aluminium monocoque, based on space frame principles, which helped to significantly reduce weight without being any less rigid.  Audi AG refers to this type of construction as the "Audi Space Frame" (ASF).  It is technically the first 'original' D platform.

Audi A8 (1994–2003)
Audi S8 (1996–2003)

D3
The D3 platform, also employing an aluminium space frame, was used for the second generation Audi A8, A8L, and S8.

Audi A8 (2003–2010)
Audi S8 (2006–2010)

D1 (VW Phaeton/Bentley)
The D1 platform cars (not to be confused with the earlier Audi V8 platform) share some components with the D3 platform, but have conventional steel bodyshell construction.

Bentley Continental GT (Typ 3W, 2004–2018)
Bentley Flying Spur (Typ 3W, 2005–2019)
Volkswagen Phaeton (Typ 3D, 2003–2016)
Porsche Panamera (Typ 3D, 2010-2016)

D4
The third generation Audi A8 launched in 2009 is sometimes referred to as the "D4" generation A8. This model combines an aluminium Audi Space Frame (ASF) structure but no longer uses the D platform, but the Audi-developed MLB component matrix.

D5
The Fourth generation Audi A8 launched in 2018 is sometimes referred to as the "D5" generation A8. This model combines an aluminium Audi Space Frame (ASF) structure but no longer uses the D platform, but the Audi-developed MLB Evo.

References

External links
Volkswagen Group corporate website

D