omniomni/omni-engineering huggingface dataset:
Gashing. Gashing is a machining process used to rough out coarse pitched gears and sprockets. It is commonly used on worm wheels before hobbing, but also used on internal and external spur gears, bevel gears, helical gears, and gear racks. The process is performed on gashers or universal milling machines, especially in the case of worm wheels. After gashing the gear or sprocket is finished via hobbing, shaping, or shaving.

Equipment
Gashers are large, heavy-duty machine tools. They have horizontal and vertical slideways, precise indexing, large diameter ballscrews, and spindle drive motors up to . They are usually controlled via computer numerical control (CNC) or a microprocessor. While they are usually used for rough cutting, they are also sometimes used for finishing. For example, gashers are used for the production of large roller-chain sprockets.

Process
Gashing was first used to rough out worm wheels using a universal milling machine, but then dedicated gashers were built to rough out other types of gears. Because the processes is carried out on two different machines the process differs.

Universal milling machine
The process uses a milling cutter with a cross-section that is slightly smaller than the final cross-section of the cut; it has the same diameter as the worm. The cutter is then angled to the gashing angle. The gashing angle is calculated from the lead and pitch diameter of the worm; often tables are available with the gashing angles for common diameters and leads. The cutter is centered over the blank and then plunged into it to the proper depth. The cutter is finally withdrawn and the blank indexed to the next tooth space and cut. This is repeated until all of the tooth spaces have been cut.

Note that a standard endmill with rounded corners can be used instead if a special milling cutter is unavailable. The endmill should be  the pitch diameter.

Note that is process cannot be used on a small worm wheel that mate with a multiple threaded worm.

Gasher

The process is similar to that outlined for the universal milling machine except a gashing angle is not used. When gashing spur gears, racks, or bevel gears the cutter is plunged into the workpiece and then moved linearly in the proper direction. If a helical gear is being roughed out, then the table rotates and moves along the vertical axis to interpolate the helical path.

The two most common cutting tools are formed milling cutters and cutters with indexable carbide inserts. For very large gears a cutter might be replaced with two slitting cutters that cut triangular slugs from the blank.

References

Bibliography
.
.
.

External links
Table of gashing angles

Gears
Machining
Megafortress. Megafortress (also known as Megafortress: Flight Of The Old Dog) is a flight simulation video game developed by Artech Digital Entertainment and released by Three-Sixty Pacific Inc in 1991. The game takes place in the late 1980s and early 1990s and features three distinct sets of missions: Red Flag (USAF) training exercises at Nellis Air Force Base in Nevada, a fictional series of missions during the First Gulf War, and a special mission which reenacts the plot of the novel Flight of the Old Dog.

Gameplay
The game is played as a 1st person flight simulator. The player can fly the EB-52 from six stations ranging from the pilot's station to the electronic warfare officer's station.

A player earns a promotion from successfully completing a set of 5 missions. The highest rank that can be achieved in the game is brigadier general (35 missions). If the player completes the special mission known as Flight of the Old Dog, they are immediately promoted to brigadier general. However, after the player completes 99 missions, they are automatically retired.

Release
The packaging illustration was done for Three Sixty Pacific by Bay area illustrator Marc Ericksen, who had previously created cover art on four battle sets of the V for Victory series, as well as their release of Das Boot.

Two add-ons were published, Megafortress: Operation Sledgehammer (1991) and Megafortress: Operation SkyMaster (1992).

Reception

Computer Gaming World in 1992 favorably reviewed the game's graphics, interface, and sound card audio, and recommended it to players "looking for a game with more emphasis on strategy and less seat-of-the-pants dogfighting". A survey that year of wargames with modern settings gave the game four and a half stars out of five. and the magazine named it one of the year's best simulation games. In a 1994 survey of wargames the magazine gave the title four stars out of five,

References

External links

1991 video games
Amiga games
Artech Studios games
DOS games
Flight simulation video games
Military of the United States in fiction
Single-player video games
Three-Sixty Pacific games
Video games developed in Canada
Cobalt(II) cyanide. Cobalt(II) cyanide is  the inorganic compound with the formula Co(CN)2.  It is coordination polymer that has attracted intermittent attention over many years in the area of inorganic synthesis and homogeneous catalysis.



Uses
Cobalt(II) cyanide has been used as a precursor to dicobalt octacarbonyl.

Preparation and structure
The trihydrate salt is obtained as a reddish-brown precipitate by adding two equivalents of potassium cyanide to a cobalt salt solution:
CoCl2(H2O)6 + 2 KCN → Co(CN)2 + 2 KCl  +  6 H2O
With excess cyanide, the red brown dicyanide dissolves to give pentacyanocobaltate.

Solid  cobalt(II) cyanide is a coordination polymer consisting of cobalt ions linked by cyanide units in a cubic arrangement, each such cobalt atom having octahedral geometry, and an additional cobalt atom in half of the cubic cavities. That is, the structure is actually Co[Co(CN)3]2 in a zeolite-like structure. It forms hydrates and other inclusion complexes by having substances diffuse into the cavities that do not contain the cobalt atoms.

References

Cobalt(II) compounds
Cyanides
Diphenyl carbonate. Diphenyl carbonate is the organic compound with the formula (C6H5O)2CO.  It is classified as an acyclic carbonate ester.  It is a colorless solid.  It is both a monomer in combination with bisphenol A in the production of polycarbonate polymers and a product of the decomposition of polycarbonates.

Production
World production capacity of diphenyl carbonate was 254,000 tonnes in 2002, and phosgenation of phenol is the most significant route. Phosgenation of phenol can proceed under various conditions. The net reaction is as follows:

 2 PhOH + COCl2 → PhOCO2Ph + 2 HCl

The use of phosgene can be avoided by the oxidative carbonylation of phenol with carbon monoxide:

 2 PhOH + CO + [O] → PhOCO2Ph + H2O

Dimethyl carbonate can also be transesterified with phenol:

 CH3OCO2CH3 + 2 PhOH → PhOCO2Ph + 2 MeOH

The kinetics and thermodynamics of this reaction are not favorable. For example, at higher temperatures, dimethyl carbonate undesirably methylates phenol to give anisole.  Despite this, diphenyl carbonate made from non-phosgene sources has become a widely used raw material for the synthesis of bisphenol-A-polycarbonate in a melt polycondensation process.

Applications
Polycarbonates can be prepared by transesterifying diphenyl carbonate with bisphenol A. Phenol is a co-product. These polycarbonates may be recycled by reversing the process: transesterifying the polycarbonate with phenol to yield diphenyl carbonate and bisphenol A.

References

Monomers
Carbonate esters
Dimethyldiethoxysilane. Dimethyldiethoxysilane, sometimes abbreviated DMDEOS or DMDES, is an organosilicon compound. DMDEOS is a precursor in the production of the silicone polymer polydimethylsiloxane (PDMS).

DMDEOS is an intermediate silane useful for blocking hydroxyl and amino groups in organic synthesis reactions. This silylating step allows subsequent reactions to be carried out which would be adversely affected by the presence of active hydrogen in the hydroxyl or amine groups. Following the reaction step, hydroxyl or amine groups blocked with DMDEOS may be recovered by a hydrolysis procedure. DMDEOS is also used for preparing hydrophobic and release materials as well as enhancing flow of powders.

References

Monomers
Silyl ethers
Ethoxy compounds
Methyl compounds
Manganese(II) acetate. Manganese(II) acetate are chemical compounds with the formula  where n = 0, 2, 4. These materials are white or pale pink solids. Some of these compounds are used as a catalyst and as fertilizer.

Preparation
Manganese(II) acetate can be formed by treating either manganese(II,III) oxide or manganese(II) carbonate with acetic acid:

Structure
The anhydrous material and dihydrate  are coordination polymers. The dihydrate has been characterized by X-ray crystallography. Each Mn(II) center is surrounded by six oxygen centers provided by aquo ligands and acetates.

References

Manganese(II) compounds
Acetates
Neopentyl glycol. Neopentyl glycol (IUPAC name: 2,2-dimethylpropane-1,3-diol) is an organic chemical compound. It is used in the synthesis of polyesters, paints, lubricants, and plasticizers. When used in the manufacture of polyesters, it enhances the stability of the product towards heat, light, and water. By esterification reaction with fatty or carboxylic acids, synthetic lubricating esters with reduced potential for oxidation or hydrolysis, compared to natural esters, can be produced.

Reactions 
Neopentyl glycol is synthesized industrially by the aldol reaction of formaldehyde and isobutyraldehyde. This creates the intermediate hydroxypivaldehyde, which can be converted to neopentyl glycol by either a Cannizzaro reaction with excess formaldehyde, or by hydrogenation using palladium on carbon.

Owing to its tendency to form cyclic derivatives (see Thorpe-Ingold Effect), it is used as a protecting group for ketones, for example in gestodene synthesis. Similarly it gives
boronic acid esters, which can be useful in the cross coupling reactions.

A condensation reaction of neopentyl glycol with 2,6-di-tert-butylphenol gives CGP-7930.

Neopentyl glycol is a precursor to Neopentyl glycol diglycidyl ether. The sequence begins with alkylation with epichlorohydrin using a Lewis acid catalyst. Dehydrochlorination of the resulting halohydrin with sodium hydroxide affords the desired ether.

Research
It has been reported that plastic crystals of neopentyl glycol exhibit a colossal barocaloric effect (CBCEs), which is a cooling effect caused by pressure-induced phase transitions. The obtained entropy changes are about 389 joules per kilogram per kelvin near room temperature. This CBCE phenomenon is likely to be very useful in future solid-state refrigeration technologies.

See also
 Pentaerythritol
 Trimethylolethane
 Trimethylolpropane

References 

Monomers
Plasticizers
Alkanediols
Tetraphenyl butadiene. Tetraphenyl butadiene (1,1,4,4-tetraphenyl-1,3-butadiene or TPB) is an organic chemical compound used as an electroluminescent dye. It glows blue with an emission spectrum peak wavelength at 430 nm, which makes it useful as a wavelength shifter.

References

Fluorescent dyes
Aromatic hydrocarbons
Phenyl compounds
Dienes
Trimethylstibine. Trimethylstibine is an organoantimony compound with the formula Sb(CH3)3. It is a colorless pyrophoric and toxic liquid. It is synthesized by treatment of antimony trichloride and methyl Grignard reagent. It is produced by anaerobic bacteria in antimony-rich soils. In contrast to trimethylphosphine, trimethylstibine is a weaker Lewis base.  It is used in the production of some III-V semiconductors.

References

Organoantimony compounds
Methyl compounds
John Twidell. John Twidell is Director of the AMSET Centre Ltd. and is a visiting lecturer at the Environmental Change Institute, University of Oxford, and the School of Aeronautics and Engineering, City University, London.  He is Editor Emeritus of the academic journal Wind Engineering.  He co-edited the 2009 book Offshore Wind Power.

Professor Twidell previously held the Chair in Renewable Energy at De Montfort University and was Director of the Energy Studies Unit of Strathclyde University. He has served on the Boards of the British Wind Energy Association (now RenewableUK) and the UK Solar Energy Society, on committees of the Institute of Physics and as an adviser to the UK Parliamentary Select Committee on Energy. He has been a long-standing champion of wind energy.

Select bibliography

References

Living people
Year of birth missing (living people)
Academics of City, University of London
Academics of De Montfort University
Academics of the University of Oxford
Academics of the University of Strathclyde
People associated with wind power
British mechanical engineers
IXP1200. The IXP1200 is a network processor fabricated by Intel Corporation. The processor was originally a Digital Equipment Corporation (DEC) project that had been in development since late 1996. When parts of DEC's Digital Semiconductor business was acquired by Intel in 1998 as part of an out-of-court settlement to end lawsuits each company had launched at each other for patent infringement, the processor was transferred to Intel. The DEC design team was retained and the design was completed by them under Intel. Samples of the processor were available for Intel partners since 1999, with general sample availability in late 1999. The processor was introduced in early 2000 at 166 and 200 MHz. A 232 MHz version was introduced later. The processor was later succeeded by the IXP2000, an XScale-based family developed entirely by Intel.

The processor was intended to replace the general-purpose embedded microprocessors and specialized application-specific integrated circuit (ASIC) combinations used in network routers. The IXP1200 was designed for mid-range and high-end routers. For high-end models, the processor could be combined with others to increase the capability and performance of the router.

The IXP1200 integrates a StrongARM SA-1100-derived core and six microengines, which were RISC microprocessors with an instruction set optimized for network packet workloads. The StrongARM core performed non-real-time functions while the microengines manipulated network packets. The processor also integrates static random access memory (SRAM) and synchronous dynamic random access memory (SDRAM) controllers, a PCI interface and an IX bus interface.

The IXP1200 contains 6.5 million transistors and measures 126 mm2. It was fabricated in a 0.28 μm, complementary metal–oxide–semiconductor (CMOS) process with three levels of interconnect. It was packaged in a 432-ball enhanced ball grid array (EBGA). The IXP1200 was fabricated at DEC's former Hudson, Massachusetts plant.

Notes

References 

 Halfhill, Tom R. (13 September 1999). "Intel Network Processor Targets Routers". Microprocessor Report.
 Matsumoto, Craig (25 August 2000). "Intel makes IXP its net processor cornerstone". EE Times.
 Article has diagram of the Intel IXP1200 Architecture.

DEC hardware
Intel products
ARM processors
Fairmat. Fairmat is a free-of-charge multi-platform software that allows to model financial contracts (e.g. a derivative contract) or projects with many contingencies (e.g. a Real Options model) by decomposing it into basic parts. Complex structures and dependencies are modelled using a graphical interface. Virtually any pay-off function and asset class( from interest rate derivatives to equity-linked notes) can be described using a simple algebraic language.

Fairmat is available for Linux, Microsoft Windows, Mac OS X and Ubuntu.

Features 
 Fairmat provides a high level abstraction and allows users to price and perform analysis for new derivative contracts or project by modelling it with a bottom-up procedure, with no knowledge of programming languages. The generated models can then be solved by using Monte Carlo simulation, binomial trees or closed form procedures (e.g. the black model).
 The information about the structure of every project model is contained in an xml file and can be exchanged with third parties.
 Fairmat capabilities can be extended and specialized by plug-ins using the Mono.addins extensibility model. Available plug-ins can be found on , and while few of the plug-ins are closed source software, many of them are open source and their development can be followed on the Fairmat github page.

Open Source Plug-ins 
The following plug-ins are released under the LGPL license:

Interest rate models 

 The Hull and White one and two factors  models.
 The Pelsser squared gaussian model plug-in.

Equity models 

 The Heston stochastic volatility model plug-in.
 The Dupire local volatility model plug-in.
 The Variance Gamma  model plug-in.

Data Provider integration 

 Integration plug-ins for data from the European Central Bank , Yahoo! Finance , and MEFF

Other open source plug-ins 

 Quantum random generator support: the plug-in uses a web service provided by the university of Berlin. For more details see .

Free plug-ins 
Among the other, the following plug-in are free:

 The IAS 39 Hedge Accounting plug-in allows users to generate IAS 39 accounting reports for derivatives .
 The Geometric Brownian Motion plug-in implements the calibration of the Geometric Brownian motion model using different techniques .

Commercial plug-ins 

 The Economic Scenarios Generator plug-in generates market consistent risk-neutral and real-world economic scenarios for  several asset classes such as zero coupon bonds (ZCB), Inflation Rates, defaultable bonds / credit spreads and baskets of equities and indices

Related services 
From version 1.4 Fairmat supports an on-demand data pricing service offered by the same producers.

Financial software
Wetting transition. A wetting transition (Cassie–Wenzel transition) may occur during the process of wetting of a solid (or liquid) surface with a liquid. The transition corresponds to a certain change in contact angle, the macroscopic parameter characterizing wetting. Various contact angles can co-exist on the same solid substrate. Wetting transitions may occur in a different way depending on whether the surface is flat or rough.

Flat surfaces
When a liquid drop is put onto a flat surface, two situations may result. If the contact angle is zero, the situation is referred to as complete wetting. If the contact angle is between 0 and 180°, the situation is called partial wetting. A wetting transition is a surface phase transition from partial wetting to complete wetting.

Rough surfaces
The situation on rough surfaces is much more complicated. The main characteristic of the wetting properties of rough surfaces is the so-called apparent contact angle (APCA). It is well known that the APCA usually measured are different from those predicted by the Young equation. Two main hypotheses were proposed in order to explain this discrepancy, namely the Wenzel and Cassie wetting models. According to the traditional Cassie model, air can remain trapped below the drop, forming "air pockets". Thus, the hydrophobicity of the surface is strengthened because the drop sits partially on air. On the other hand, according to the Wenzel model the roughness increases the area of a solid surface, which also geometrically modifies the wetting properties of this surface. Transition from Cassie to Wenzel regime is also called wetting transition. Under certain external stimuli, such as pressure or vibration, the Cassie air trapping wetting state could be converted into the Wenzel state. Apart from external stimuli, intrinsic contact angle of the liquid (below or above 90 degree), liquid volatility, structure of cavities (reentrant or non-reentrant, connected or unconnected) are known to be important factors determining the rate of wetting transition. Complex structures such as hierarchical structures, and concave structures are reported to prevent wetting transition. It is well accepted that the Cassie air trapping wetting regime corresponds to a higher energetic state, and the Cassie–Wenzel transition is irreversible. However, the mechanism of the transition remains unclear. It was suggested that the Cassie–Wenzel transition occurs via a nucleation mechanism starting from the drop center. On the other hand, recent experiments showed that the Cassie–Wenzel transition is more likely to be due to the displacement of a triple line under an external stimulus. The existence of so-called impregnating Cassie wetting state also has to be considered.  Understanding wetting transitions is of a primary importance for design of superhydrophobic surfaces.

See also
Surface tension

References

Fluid mechanics
Surface science
UVW. UVW may refer to:

 The CIE 1964 color space, often abbreviated as UVW
 , an umbrella organization for Dutch water boards
 United Vehicle Workers, a former trade union in Britain (1919 - 1922)
 United Voices of the World, an independent grassroots trade union in Britain
 , an Austrian academic publisher
 UVW mapping, a mathematical technique for coordinate mapping
 University of Virginia's College at Wise, a public liberal arts college in Wise, Virginia
 Unloaded Vehicle Weight, the weight of a vehicle as manufactured at the factory
Ascalaph Designer. Ascalaph Designer is a computer program for general purpose molecular modelling for molecular design and simulations. It provides a graphical environment for the common programs of quantum and classical molecular modelling ORCA, NWChem, Firefly, CP2K and MDynaMix 
. The molecular mechanics calculations cover model building, energy optimizations and molecular dynamics. Firefly (formerly named PC GAMESS) covers a wide range of quantum chemistry methods. Ascalaph Designer is free and open-source software, released under the GNU General Public License, version 2 (GPLv2).

Key features

Uses

See also
 List of software for molecular mechanics modeling
 Molecular design software
 Molecule editor
 Abalone

References

External links 
 
 SourceForge
 Twitter

Computational chemistry software
Free science software
Molecular modelling software
Molecular dynamics software