omniomni/omni-engineering huggingface dataset:
Flow diagram. Flow diagram is  a diagram representing a flow or set of dynamic relationships in a system. The term flow diagram is also used as a synonym for flowchart, and sometimes as a counterpart of the flowchart.     

Flow diagrams are used to structure and order a complex system, or to reveal the underlying structure of the elements and their interaction.

Overview 
The term flow diagram is used in theory and practice in different meanings. Most commonly the flow chart and flow diagram are used in an interchangeable way in the meaning of a representation of a process. For example the Information Graphics: A Comprehensive Illustrated Reference by Harris (1999) gives two separate definitions: 
Flow chart or flow diagram... is a diagram that visually displays interrelated information such as events, steps in a process, functions, etc., in an organized fashion, such as sequentially or chronologically.
Flow diagram [is] a graphic representation of the physical route or flow of people, materials, paperworks, vehicles, or communication associated with a process, procedure plan, or investigation.

In the second definition the meaning is limited to the representation of the physical route or flow. An example of such a diagram is the illustration of the flows in a nuclear submarine propulsion system, which shows different streams back and forth in the system. The representation of such a system can be supplemented by one or more flowcharts, which show the sequence of one of the flows in one direction, or any of the control flows to manage the system.  

The physical movement of objects from one location to another can also be visualized in a mix of maps and flowchart or sankey diagram, which are called flow maps. Flow maps can indicate on a map, what flows, moves or migrates, in which direction, and in which quantities etc.

Specific types of flow diagrams 

In theory and practice specific types of diagrams are also called a type of flow diagrams, such as:
 Alluvial diagram, highlights and summarizes the significant structural changes in networks
 Circular flow of income
 Control flow diagram, a diagram to describe the control flow of a business process, process or program
 Cumulative flow diagram, a tool used in queuing theory
 Functional flow block diagram, in systems engineering
 Data flow diagram, a graphical representation of the flow of data through an information system
 Dynamic stock and flow diagram
 Information flow diagram, an illustration of information flow throughout an organisation
 Process flow diagram, in Operations, a graphical representation of a process
 Product flow diagram (PFD), a graphical representation of the order by which a sequence of products is created according to Product based planning principles
 A form of rap notation known as "flow diagram"
 Sankey diagram, where line width represents magnitude
 Signal-flow graph, in mathematics, a graphical means of showing the relations among the variables of a set of linear algebraic relations
 State diagram, a representation of a finite state machine

See also 
 Flow graph (disambiguation)
 Function model
 Visual programming language

References 

Diagrams
VCF. VCF may refer to:

Organizations
 Valencia CF, a Spanish professional football club in Valencia
 Victory (church) (formerly VCF), an evangelical Protestant church based in the Philippines

Technology
 Variant Call Format, the format of a text file used in bioinformatics for storing gene sequence variations
 vCard, a file format standard for electronic business cards
 Virtual Case File, a software application developed by the United States Federal Bureau of Investigation
 VMware Cloud Foundation, an infrastructure platform for hybrid cloud management of the VMware Infrastructure product line
 Voltage-controlled filter, an electronic filter whose operating characteristics can be set by an input control voltage
 Volume correction factor, a standardized computed factor used to correct for the thermal expansion of fluids

Other
 September 11th Victim Compensation Fund, an act of the US Congress to compensate the victims of the September 11 attacks
 VCF, one of several brands of spermicide
 Vintage Computer Festival, an international event celebrating the history of computing

See also
VFC (disambiguation)
Common Support Aircraft. The Common Support Aircraft (CSA) was a proposed concept, which has been considered by the United States Navy since at least the early 1990s, to replace a number of different fixed-wing aircraft capable of operating from an aircraft carrier and which serve a "support" function, with a single type of aircraft or aircraft platform able to perform all support tasks.

Current roles deemed "support" by the Navy include: carrier on-board delivery (COD), electronic surveillance (ES), electronic warfare (EW), and airborne early warning (AEW).  Another possible support role for a carrier-based aircraft is that of aerial refueling.

Among combat roles, while anti-submarine warfare (ASW) and anti-surface warfare (ASUW) are sometimes also considered "support"; fighter, bomber, and ground attack roles are not.

Current carrier-based fixed-wing support aircraft used by the US Navy, and which would presumably be replaced by the CSA, include:
C-2 Greyhound, for COD
E-2 Hawkeye, for AEW

Other support aircraft used by the US Navy in the recent past include:
S-3 Viking, for ASW, ASUW, and recovery tanking
ES-3 Shadow, for ES
EA-6B Prowler, for EW
KA-6D, for mission tanking

External links
Common Support Aircraft (CSA) on GlobalSecurity.org
"Common Support Aircraft(CSA)" on The Federation of American Scientists(FAS)web-site
Chimera, Wombat/Joey, Crossbow, and Penguin CSA study designs

Carrier-based aircraft
Lampoldshausen. Lampoldshausen is a small village on the southern edge of the Harthausen Forest near Möckmühl in Baden-Württemberg, Germany.

Aerospace Village
Within the global Aerospace community Lampoldshausen is known as Aerospace Village by the Institute of space propulsion of the German Aerospace Center (DLR) for research and hot firing test of rocket engines, especially for Ariane launchers as well as the Orbital Propulsion Centre of ArianeGroup, the European competence centre for spacecraft propulsion.

The ArianeGroup site is the European competence centre for development and production of satellite and orbital platform propulsion systems. It produces chemical and electrical propulsion systems, high-precision components for satellite and launcher attitude control systems, and the complete UPS (Unified Propulsion System).

Additionally, Lampoldshausen is part of the Community of Ariane Cities (CVA).

References

External links
http://www.dlr.de/dlr/en/desktopdefault.aspx/tabid-10259/
http://www.raumfahrtantriebe.de/history/main.html
http://www.ariane.group/en/about-us/our-main-facilities-and-locations/

Villages in Baden-Württemberg
Aleksandr Arkhangelsky. Aleksandr Aleksandrovich Arkhangelsky (, 1892 – 18 December 1978) was a Soviet and Russian aircraft designer and doctor of technical sciences. Hero of Socialist Labour (1947)

Biography
Arkhangelsky was born in 1892, and graduated from MVTU in 1918. During his studies, he worked at the aerodynamic laboratory headed by Nikolay Zhukovsky, then worked at TsAGI from 1918 to 1936.

He designed and built several aerosleds ARBES along with B. S. Stechkin. After the establishment of the aircraft design bureau of Andrei Tupolev at TsAGI, he participated in all ANT designs.

In 1932, he was appointed chief of the department of high-speed aircraft. He was the leading designer of the first Soviet bomber, the ANT-40 (SB), and its transport development, the PS-35. From 1936 on, he was chief of the bureau and responsible for large-scale production of the SB. He was the chief designer of the Ar-2.

Arhangelsky OKB rejoined Tupolev OKB in 1941. In 1947, he became first deputy chief designer.

He was the uncle of mathematician Alexander Arhangelskii.

He died in 1978.

References
https://web.archive.org/web/20050221050008/http://www.aviation.ru/okb.php

1892 births
1978 deaths
Bauman Moscow State Technical University alumni
Central Aerohydrodynamic Institute employees
Heroes of Socialist Labour
Recipients of the Stalin Prize
Recipients of the Lenin Prize
Recipients of the Order of Lenin
Recipients of the Order of the Red Banner of Labour
Recipients of the Order of the Red Star
Russian aerospace engineers
Soviet aerospace engineers
Soviet inventors
Soviet mechanical engineers
Burials at Novodevichy Cemetery
Graduates of the 4th Moscow Gymnasium
Nascent hydrogen. Nascent hydrogen is an outdated concept in organic chemistry that was once invoked to explain dissolving-metal reactions, such as the Clemmensen reduction and the Bouveault–Blanc reduction. Since organic compounds do not react with H2, a special state of hydrogen was postulated. It is now understood that dissolving-metal reactions occur at the metal surface, and the concept of nascent hydrogen has been discredited in organic chemistry. However, the formation of atomic hydrogen is largely invoked in inorganic chemistry and corrosion sciences to explain hydrogen embrittlement in metals exposed to electrolysis and anaerobic corrosion (e.g., dissolution of zinc in strong acids (HCl) and aluminium in strong bases (NaOH)). The mechanism of hydrogen embrittlement was first proposed by Johnson (1875). The inability of hydrogen atoms to react with organic reagents in organic solvents does not exclude the transient formation of hydrogen atoms capable to immediately diffuse into the crystal lattice of common metals (steel, titanium) different from these of the platinoid group (Pt, Pd, Rh, Ru, Ni) which are well known to dissociate molecular dihydrogen (H) into atomic hydrogen.

History 
The idea of hydrogen in the nascent state having chemical properties different from those of molecular hydrogen developed the mid-19th century.  Alexander Williamson repeatedly refers to nascent hydrogen in his textbook Chemistry for Students, for example writing of the substitution reaction of carbon tetrachloride with hydrogen to form products such as chloroform and dichloromethane that the "hydrogen must for this purpose be in the nascent state, as free hydrogen does not produce the effect".  Williamson also describes the use of nascent hydrogen in the earlier work of Marcellin Berthelot.  Franchot published a paper on the concept in 1896, which drew a strongly worded response from Tommasi who pointed to his own work that concluded "nascent hydrogen is nothing else than H + x calories".

The term "nascent hydrogen" continued to be invoked into the 20th century.

Reducing agents at low and high pH 
Devarda's alloy (alloy of aluminium (~45%), copper (~50%) and zinc (~5%)) is a reducing agent that was commonly used in wet analytical chemistry to produce in situ so-called nascent hydrogen under alkaline conditions for the determination of nitrates () after their reduction into ammonia (). 

In the Marsh test, used for arsenic determination (from the reduction of arsenate () and arsenite () into arsine ()), hydrogen is generated by contacting zinc powder with hydrochloric acid. 

So, hydrogen can be conveniently produced at low or high pH, according to the volatility of the species to be detected. Acid conditions in the Marsh test promote the fast escape of the arsine gas (AsH3), while under hyperalkaline solution, the degassing of the reduced ammonia (NH3) is greatly facilitated (the ammonium ion  being soluble in aqueous solution under acidic conditions).

See also 
 Atomic hydrogen welding

References

Further reading

Hydrogen
Electrolysis
Hydrogen
Obsolete theories in chemistry
ShaBLAMM! NiTro-VLB. The ShaBLAMM! NiTro-VLB was a computer system that used a QED R4600 microprocessor implemented on a VESA Local Bus peripheral card and designed to function when connected to a host computer system using an Intel i486.  The NiTro-VLB conformed to the ARC standard, and was produced and marketed by ShaBLAMM! Computer as an "upgrade" card for accelerating Windows NT.

Characteristics
The NiTro-VLB is notable for various unique characteristics among personal computer accessories.  For example, although the system was marketed as an "upgrade" for computers already using a 486 processor, the NiTro-VLB was in fact of an entirely different architecture (specifically, the MIPS architecture) from the IA32-based 486.  Further, as a "parasitic" or "symbiotic" coprocessor, the NiTro-VLB was designed to co-opt the host 486 processor from running, and used four megabytes of the host 486 motherboard's system memory as a DMA buffer (although the NiTro-VLB required its own separate DRAM main memory, in addition to any memory installed on the host 486 motherboard). 

This is a type of "parasite"/"host" upgrade card configuration, in which an entire motherboard and processor are implemented on an expansion card designed to connect to a host motherboard's expansion slot.  Such configurations are rare among computer systems designed to run Microsoft Windows.

Specifications and benchmarks
The NiTro-VLB's QED R4600 processor, running at 100 MHz, was rated at 73.8 SPECint92 and 63 SPECfp92 (which are similar figures to the first-generation Pentium running at 66 MHz).  Faster and costlier versions were designed to run at 133 MHz or 150 MHz.

Sales
Initially, the NiTro-VLB system was priced at $1,095 for a 100 MHz card with no main memory, $1,995 for a 100 MHz card with 16 MB of main memory and a copy of Windows NT, and $2,595 for a 150 MHz card.

See also
DeskStation Tyne
Jazz (computer)
MIPS Magnum

External links
A BYTE magazine article detailing the ShaBlamm! Nitro-VLB

Computer workstations
Advanced RISC Computing
Phosphosilicate glass. Phosphosilicate glass, commonly referred to by the acronym PSG, is a silicate glass commonly used in semiconductor device fabrication for intermetal layers, i.e., insulating layers deposited between succeedingly higher metal or conducting layers, due to its effect in gettering alkali ions.  Another common type  of phosphosilicate glass is borophosphosilicate glass (BPSG).

Soda-lime phosphosilicate glasses also form the basis for bioactive glasses (e.g. Bioglass), a family of materials which chemically convert to mineralised bone (hydroxy-carbonate-apatite) in physiological fluid.

Bismuth doped phosphosilicate glasses are being explored for use as the active gain medium in fiber lasers for fiber-optic communication.

See also
 Wafer (electronics)

References 

Glass compositions
Semiconductor device fabrication
Borophosphosilicate glass. Borophosphosilicate glass, commonly known as BPSG, is a type of silicate glass that includes additives of both boron and phosphorus.  Silicate glasses such as PSG and borophosphosilicate glass are commonly used in semiconductor device fabrication for intermetal layers, i.e., insulating layers deposited between succeedingly higher metal or conducting layers.

BPSG has been implicated in increasing a device's susceptibility to soft errors since the boron-10 isotope is good at capturing thermal neutrons from cosmic radiation.  It then undergoes fission producing a gamma ray, an alpha particle, and a lithium ion.  These products may then dump charge into nearby structures, causing data loss (bit flipping, or single event upset).

In critical designs, depleted boron consisting almost entirely of boron-11 is used to avoid this effect as a radiation hardening measure. Boron-11 is a by-product of the nuclear industry.

References 

Semiconductor device fabrication
Glass compositions
Boron compounds
Kinematoscope. The Kinematoscope (a.k.a. Motoscope) was patented in 1861 (United States Patent 31357), a protean development in the history of cinema. The invention aimed to present the illusion of motion.

The patent was filed by Coleman Sellers of Philadelphia, Pennsylvania as an "improvement in exhibiting stereoscopic pictures". Coleman applied stereoscopy to the existing principle of toy phantasmascopes using rotating discs.

A series of still stereographic images with successive stages of action were mounted on blades of a spinning paddle and viewed through slits. The slits passed under a stereoscopic viewer. The pictures were visible within a cabinet, and were not projected onto a screen.

References

External links
 patent of kinemstoscope on google

Audiovisual introductions in 1861
History of film
Photographic techniques
American inventions
Arkhangelski. The Arkhangelsky Design Bureau was a short-lived Soviet military aircraft design bureau headed by Alexander Arkhangelsky. Formerly working for Andrei Tupolev, Arkhangelsky became the leader of Tupolev's design bureau after Tupolev was arrested in 1938 during the Great Purge and was tasked to develop a dive-bomber version of the Tupolev SB (the Arkhangelsky Ar-2). The bureau resumed its original name when Tupolev was released from prison after the Axis powers invaded the Soviet Union in June 1941.

Aircraft
Arkhangelsky Ar-2

Citations

Bibliography

Aircraft manufacturers of the Soviet Union
1940 establishments in the Soviet Union
1941 disestablishments in the Soviet Union
Darcy (unit). The darcy (or darcy unit) and millidarcy (md or mD) are units of permeability, named after Henry Darcy. They are not SI units, but they are widely used in petroleum engineering and geology. The unit has also been used in biophysics and biomechanics, where the flow of fluids such as blood through capillary beds and cerebrospinal fluid through the brain interstitial space is being examined. A darcy has dimensions of length2.

Definition
Permeability measures the ability of fluids to flow through rock (or other porous media).  The darcy is defined using Darcy's law, which can be written as:

where:
{|
| || is the volumetric fluid flow rate through the medium
|-
| || is the area of the medium
|-
| || is the permeability of the medium
|-
| || is the dynamic viscosity of the fluid
|-
| || is the applied pressure difference
|-
| || is the thickness of the medium
|}

The darcy is referenced to a mixture of unit systems.  A medium with a permeability of 1 darcy permits a flow of 1 cm3/s of a fluid with viscosity 1 cP (1 mPa·s) under a pressure gradient of 1 atm/cm acting across an area of 1 cm2.

Typical values of permeability range as high as 100,000 darcys for gravel, to less than 0.01 microdarcy for granite. Sand has a permeability of approximately 1 darcy. 

Tissue permeability, whose measurement  is still in its infancy, is somewhere in the range of 0.01 to 100 darcy.

Origin
The darcy is named after Henry Darcy. Rock permeability is usually expressed in millidarcys (md) because rocks hosting hydrocarbon or water accumulations typically exhibit permeability ranging from 5 to 500 md.

The odd combination of units comes from Darcy's original studies of water flow through columns of sand.  Water has a viscosity of 1.0019 cP at about room temperature.

The unit abbreviation "d" is not capitalized (contrary to industry use). The American Association of Petroleum Geologists uses the following unit abbreviations and grammar in their publications:

 darcy (plural darcys, not darcies): d
 millidarcy (plural millidarcys, not millidarcies): md

Conversions
Converted to SI units, 1 darcy is equivalent to  or 0.9869233 μm2.  This conversion is usually approximated as 1 μm2. This is the reciprocal of 1.013250—the conversion factor from atmospheres to bars.

Specifically in the hydrology domain, permeability of soil or rock may also be defined as the flux of water under hydrostatic pressure (≈ 0.1 bar/m) at a temperature of 20 °C. In this specific setup, 1 darcy is equivalent to 0.831 m/day.

References

 Richard Selley's "Elements of Petroleum Geology (2nd edition)," page 250.

Units of measurement
Hydraulics
Hydraulic engineering
Hydrology
Hydrogeology
Soil mechanics
Soil physics
Félix Soto Toro. Félix Soto Toro  (born 1967), is an electrical designs engineer at NASA, who developed the Advanced Payload Transfer Measurement System.

Early years
Soto Toro was raised in a poor section of the City of Guaynabo, Puerto Rico known as El Barrio Amelia.  As a child, he was interested in everything that had to do with light bulbs and electricity. He obtained his primary and secondary education in his hometown and went to high school at the Colegio Madre Cabrini in San Juan.

In 1984, after graduating from high school, Soto Toro enrolled at the Florida Institute of Technology, located in Melbourne, Florida where he earned a Bachelor's degree in electrical engineering. In 1986, while in college, he decided that he would like to become an engineer for NASA. Soto Toro participated in the Cooperative Education Program.

Career at NASA
In 1990, Soto Toro earned his bachelor's degree in science in electrical engineering.  He was hired by NASA, a month after graduating and assigned to the Design Engineering Networks Communications section at Kennedy Space Center.  In 1992, he completed his master's degree in science in electrical engineering, and by 1997, he completed another Masters in Science Degree.  By specializing in the communications field of electrical engineering, he improved his credentials towards his goal of becoming an astronaut.

At the Kennedy Space Center, Soto Toro reviews, designs, builds, tests and implements engineering designs used in the Space Shuttle and Payload Operations Development Laboratories.  The main project he developed was the Advanced Payload Transfer Measurement System, which consists of a simplified, robust, centrally operated and portable system that automatically measures the spherical coordinates offset between the trunnion and their supports during transfer operations.  Soto Toro earned his Doctorate of Philosophy degree in Electrical Engineering and applied to become an astronaut candidate.

In NASA, Soto Toro works with testing ground support equipment used in pre-launch, launch and post-launch activities.

Honors
Soto Toro was presented with the 2003 "El Premio Coqui" by La Casa de Puerto Rico in Florida for his contributions in the field of science.  On November 9, 2003, Soto Toro, along with another Puerto Rican astronaut applicant, Henry Bursian Berríos, and Ninfa Segarra, who was the first Hispanic Deputy Mayor of New York City, were named the Grand Marshals of the Puerto Rican Day Parade held in Palm Bay, Florida. Soto Toro was twice given the Puerto Rico Role Model Award, by the Puerto Rico School system.

See also

 List of Puerto Ricans
 Puerto Rican scientists and inventors
 List of Puerto Ricans in the United States Space Program

Notes

References

Soto Toro, Felix
People from Guaynabo, Puerto Rico
Florida Institute of Technology alumni
Soto Toro, Felix
NASA people
21st-century Puerto Rican scientists
Puerto Rican inventors
21st-century American inventors