omniomni/omni-engineering huggingface dataset:
Valley-fill circuit. A valley-fill circuit is a type of passive power-factor correction (PFC) circuit.
For purposes of illustration, a basic full-wave diode-bridge rectifier is shown in the first stage, which converts the AC input voltage to a DC voltage.

Operation
When the AC voltage is applied, the rectified line voltage is applied across C1 and C2, as they are both charged via D3 and R1, until C1 and C2 are each charged up to approximately half of the peak line voltage. 

When the line voltage falls below the peak, into the "valley" phase, Vout begins to fall toward half of the peak line voltage.  At this point, C1 and C2 begin to discharge into the load at Vout, via D1 and D2 respectively.   

R1 is needed to prevent a large in-rush current, and electromagnetic interference (EMI).

Advantages and disadvantages
An advantage of this design is that it is rather simple.  A disadvantage is that the ripple voltage can still be 50% of peak, and have total harmonic distortion (THD) of 35%, which is rather high. A 1998 United States patent, US6141230A, provides a power factor of 0.98 and a THD of 9.61% and is most suited to constant load applications such as fluorescent lamp ballasts.

References 

Electric power
Electrical circuits
Mars-Grunt. Mars-Grunt, also known as Expedition-M (), is a proposed robotic Mars sample-return mission. It was proposed to the Russian Federal Space Agency (Roscosmos) by the Russian Space Research Institute.

As of September 2023, Mars-Grunt is expected to be sent to Mars following the success of Boomerang (Fobos-Grunt-2), which in turn is expected sometime after 2030.

Lander
If funded by the Russian space agency Roscosmos, it would be developed by the Russian Space Research Institute and NPO Lavochkin, based on Fobos-Grunt technology. 
Designs show a dome-shaped lander would separate from the orbiter and would enter the Martian atmosphere protected within an inflatable rubber braking cone and fire retrorockets for a soft landing. Once a robotic arm selects and retrieves the samples (mass about ), a small rocket in the top of the lander would blast the ascent vehicle for rendezvous and docking with the orbiter for the soil sample transfer into the return vehicle.

Cruise stage
The cruise stage PM (from Pereletny Modul ) is sometimes referred to as Flagman. It was developed for the Fobos-Grunt mission, but its basic architecture is promised to be the base for a whole generation of future planetary missions, including Luna-Glob, Luna-Resurs and Luna-Grunt to the Moon; Venera-D to Venus; Mars-NET and Mars-Grunt to Mars and, possibly, Sokol-Laplas to Jupiter. The platform's developer - NPO Lavochkin - stressed that in different configuration, the same bus could be adapted as an orbiter or as a lander.

Status 

If the technology being developed for Luna Glob to the Moon, and Fobos-Grunt-2 to Mars' moon Phobos, is proved successful, it will then be used on Mars-Grunt.

Tasks 

Tasks set by the NPO Lavochkin and Roscosmos:

 Delivery of substance samples from Mars to Earth
 Refinement of engineering and technical models of the atmosphere and surface of Mars
 Detailed geochemical analysis of soil substance on Mars
 Study of the interaction processes between the atmosphere, solar radiation, and the surface of Mars

See also

Phobos program

References

 

Proposed space probes
Missions to Mars
Russian space probes
Sample return missions
2030s in spaceflight
Renco Electronics. Renco Electronics is an electronics manufacturer based in Rockledge, Florida.  With facilities in the US and China, Renco makes transformers, inductors, chokes and coils.

Renco Electronics, Inc. designs and manufactures transformers and inductors in surface-mount, through-hole and chassis-mount geometries. Renco builds to print, works in conjunction with clients' engineering teams, or provides custom design to client specifications.

More than 1,000 clients buy Renco products.

Renco was founded in 1955 by John A. Rensing in Hicksville, New York, with a loan from his mother-in-law of $2,000. In 1981, the company expanded to a new facility in Deer Park, New York and relocated to its current home of Rockledge, Florida in September 1998.  After 56 years in business, Renco is thriving in the US market and now expanding to Hong Kong. John Rensing died in September 2011. After more than 20 years working at Renco, Edward. W. Rensing became the company's CEO and president.

In July 2020, Standex International acquired Renco Electronics for $28 million.

References

Electronics companies of the United States
Companies based in Brevard County, Florida
Sergio Stefanutti. Sergio Stefanutti (1906–1992) was an Italian engineer who specialized in the design of aircraft.

Biography
He joined aircraft manufacturer Società Aeronautica Italiana (later renamed SAI Ambrosini following a takeover) in the 1920s.
He was the designer of the first Italian canard fighter, the Ambrosini S.S.4, and then a touring monoplane, the Ambrosini S.7. He developed the S.7 into the Ambrosini SAI.207 and Ambrosini SAI.403; these aircraft were lightweight fighters made entirely of wood.

Stefanutti is also the first planner of a war aircraft of series operating by remote control, built by Aerolombarda and ready for operations during the period of armistice. In the postwar Stefanutti was applied to the reaction flight, coming to plan and then to realize the first hunting jet plane of national planning, that takings the name of Aerfer Sagittario 2. This aircraft is visible in the Italian Air Force Museum near Bracciano (Rome); together with the following development that it also foresaw the use of a rocket besides the turbojet to increase the push and the speed of interception. This aircraft, in the second variation, is the first Italian aircraft to break the sound barrier; subsequently it was not adopted by Italian Air Force.

Bibliography

Ciampaglia, Giuseppe: "Dal SAI Ambrosini Sagittario all'Aerfer Leone. Storia dei primi caccia supersonici italiani realizzati da Sergio Stefanutti". IBN editore Roma 2004 .

External links
Sergio Stefanutti
Immagini e descrizione del SAI Ambrosini S.S.4
Immagine del SAI Ambrosini 207

1906 births
1992 deaths
20th-century Italian people
Italian aerospace engineers
People from Udine
Cyclopentadienyliron dicarbonyl iodide. Cyclopentadienyliron dicarbonyl iodide is an organoiron compound with the formula (C5H5)Fe(CO)2I. It is a dark brown solid that is soluble in common organic solvents.  (C5H5)Fe(CO)2I, or FpI as it is often known, is an intermediate for the preparation of other organoiron compounds such as in ferraboranes.

Preparation
Cyclopentadienyliron dicarbonyl iodide is synthesized by the reaction of cyclopentadienyliron dicarbonyl dimer with I2:
Cp2Fe2(CO)4 + I2 → 2 CpFe(CO)2I

It was first reported by Pauson and Hallam.

Structure
The compound has Cs symmetry, with a mirror plane intersecting one carbon of the Cp ring as well as the iron and iodide centre. The compound adopts a piano stool structure: the cyclopentadienyl ligand is the "seat" and three other ligands are "legs". Such compounds are members of the half-sandwich family of compounds, which is a subgroup of the metallocenes. X-ray crystallography shows the following features: Fe-Cp centroid = 1.72, Fe-I = 2.61, and Fe-CO = 1.78 Å.

Electron counting of this iron(II) complex indicates that (C5H5)Fe(CO)2I is an 18-electron complex: using the neutral method there are 8 electrons from the iron, 5 electrons from the cyclopentadienyl anion, 2 electrons from each of the carbonyls, and 1 electron from the iodide.

References

Organoiron compounds
Coordination complexes
Carbonyl complexes
Cyclopentadienyl complexes
Half sandwich compounds
Iodo complexes
Iron(II) compounds
Liverpool-class lifeboat. The Liverpool-class motorised lifeboat was a non-self-righting boat operated by the Royal National Lifeboat Institution (RNLI) from its stations around the coast of the United Kingdom and Ireland. The boats were designed for carriage launching and were developed from the Liverpool-Class Pulling and Sailing type  of lifeboats - there were two types built, single and twin engined.

History
The Liverpool class, designed by James Barnett, was derived from the 35ft 6in Self-righting motor-class lifeboat and had many similarities with it. Lifeboatmen at many stations preferred non self-righting boats due to their better stability and the Liverpool class was designed to be light enough for carriage launching at these stations. The single-engined version entered service in 1932 and was powered by an RNLI designed, Weyburn Engineering built AE6 six-cylinder  petrol engine mounted in a watertight compartment. Like all early motor lifeboats, the Liverpool class carried an auxiliary sailing rig and had a drop keel just forward of the engine room. 28 boats were built between 1931 and 1941. The introduction of tractors to assist with carriage launching enabled the RNLI to consider a heavier, twin-engined version of the Liverpool class and a prototype was ordered but was destroyed in an air raid at the builder's yard at Cowes in May 1942. Production got underway early in 1945 and the boat was powered by two  Weyburn AE4 four-cylinder petrol engines mounted in a watertight compartment. The extra redundancy of twin engines reduced the need for auxiliary sails. 31 boats were built between 1945 and 1954, the last 21 of which were powered by  Ferry Kadenacy FKR3 diesels.
The William Cantrell Ashley now July 2017 is in dry standing Penarth marina, Cardiff.

Description
The Liverpool class was based on the  Self-righting motor introduced in 1929, but had greater beam ( rather than ) and much shallower endboxes. The shelter was extended forward to cover the engine compartment, which was watertight and allowed the engine to continue to operate as long as the air intake was not submerged. The single propeller was protected by the keel. The twin-engined variant was visually very similar but had  more beam and the twin propellers were in protective tunnels. In the mid-1960s the petrol engines in the first ten boats were replaced by  Parsons Penguin diesels (as were a couple of the Ferry engined boats). Only one single-engined boat, ON 832, was re-engined with a diesel engine, a Parsons Porbeagle of 47 hp.

Fleet

Single screw boats

Twin screw boats

References

External links
 RNLI
HomeOS. HomeOS was the working title of a home automation operating system being developed at Microsoft Research in the early 2010s. Microsoft Research announced the project in 2010 and abandoned it in 2012.

HomeOS communicated with Lab of Things, a cloud-based Internet of Things infrastructure also developed by Microsoft.

Microsoft's slogan for their HomeOS project was "Enabling smarter homes for everyone."

Microsoft's HomeOS development team has written three sample applications that make use of multiple devices, including a "sticky media" app that plays music in parts of the house that are lit up, but not other rooms; a two-factor authentication app that uses audio from smartphones and images from a front-door camera to turn on lights when a user is identified; and a home browser for viewing and controlling a user's access to all devices in a home.

Some staff who worked on the project cited Microsoft CEO Steve Ballmer's focus on enterprise applications,  productivity software, and cloud computing as the reason for the stalled development.

See also
Building automation
Home server
Lighting control system
LinuxMCE

References

External links 

 Official Microsoft HomeOS website

External links
 Lab of Things

Home automation
Microsoft operating systems
Microsoft Research
Kosmos 2446. Kosmos 2446 ( meaning Cosmos 2446) is a Russian US-K missile early warning satellite which was launched in 2008 as part of the Russian Space Forces' Oko programme. The satellite is designed to identify missile launches using optical telescopes and infrared sensors.

Kosmos 2446 was launched from Site 16/2 at Plesetsk Cosmodrome in Russia. A Molniya-M carrier rocket with a 2BL upper stage was used to perform the launch, which took place at 05:03 UTC on 2 December 2008. The launch successfully placed the satellite into a molniya orbit. It subsequently received its Kosmos designation, and the international designator 2008-062A. The United States Space Command assigned it the Satellite Catalog Number 33447.

References

See also
List of Kosmos satellites (2251–2500)
List of R-7 launches (2005–2009)
2008 in spaceflight

Kosmos satellites
Spacecraft launched in 2008
Oko
Spacecraft launched by Molniya-M rockets
Tamil Nadu Transmission Corporation. The Tamil Nadu Transmission Corporation Limited  (TANTRANSCO) () is an electric power transmission system operator owned by Government of Tamil Nadu.  It was established in November 2010, as a result of restructuring the Tamil Nadu Electricity Board. It is a subsidiary of TNEB Limited.

Substations
The TANTRANSCO maintains all the substations in Tamil Nadu apart from the Power Grid Corporation of India Limited (PGCIL). These substations fall under one of the following categories:
400/230 kV substations.
230/110 kV substations.
110 kV substations.
33 kV substations.

less than this kV transmissions as 22 kV and 11 kV are used for distribution.

66/11 kV substations were in use earlier. This is no longer the case anymore.

References

External links
 
 Power Grid Corporation Web-Site

Electric power transmission system operators in India
Energy in Tamil Nadu
State agencies of Tamil Nadu
State electricity agencies of India
Indian companies established in 2010
Energy companies established in 2010
Companies based in Tamil Nadu
2010 establishments in Tamil Nadu
Vidyadaan Institute of Technology and Management. Vidyadaan Institute of Technology and Management is a college established in 2010 in Buxar, Bihar, India. It is first engineering college in Bihar affiliated to Aryabhatta Knowledge University.

Academics
The college awards Bachelor of Engineering in several fields of engineering like B.Tech in Information Technology, Computer Science and Engineering, Electronics and Communications Engineering and Electrical and Electronics Engineering.

See also
 List of institutions of higher education in Bihar
 Education in Patna
 Education in Bihar
 Education in India

References

External links
 Vidyadaan Institute of Technology and Management website

Educational institutions established in 2010
2010 establishments in Bihar
Engineering colleges in Bihar
Colleges affiliated to Aryabhatta Knowledge University
Buxar district
Théodore Turrettini. Théodore Turrettini (1845–1916) was a Swiss engineer and politician.

Life 
Théodore Turrettini was trained as an engineer at the Polytechnic School of Lausanne, where he graduated in 1867. He then left Switzerland to train in a workshop in Frankfurt, and at the Siemens & Halske factory in Berlin. He later spent a short while in Paris. Back to Geneva in 1870, he became director of the "Society of Physical Instruments", a position he would keep until his death. His duties included the development of precision instruments, of machines and of drills for the St.Gothard tunnel. He also attempted to collaborate with Raoul Pictet in order to develop machines for producing cold. 

After a two-month internship at Thomas Edison's workshop in New York, he even launched himself into electric lighting. 

Turrettini's main achievement was the creation of hydroelectric power stations in Geneva, which were the most powerful of the time. 
 
Turrettini was elected an International Member of the American Philosophical Society. In 1891, Turrettini became a member of the International Niagara Commission.

References 

Paquier, Serge, "Turrettini, Théodore", in Dictionnaire Historique de la Suisse (in French).

1845 births
1916 deaths
Swiss engineers

Members of the American Philosophical Society
Unparser. In computing, an unparser is a system that constructs a set of characters or image components from a given parse tree.

An unparser is in effect the reverse of a traditional parser that takes a set of string of characters and produces a parse tree. Unparsing generally involves the application of a specific set of rules to the parse tree as a "tree walk" takes place.

Given that the tree may involve both textual and graphic elements, the unparser may have two separate modules, each of which handles the relevant components. In such cases the "master unparser" looks up the "master unparse table" to determine if a given nested structure should be handled by one module, or the other.

See also
 Bidirectional transformation
 Formal grammar
 Natural language generation

References

Syntax
Compiler construction
In situ thermal desorption. In situ thermal desorption (ISTD) is an intensive thermally enhanced environmental remediation technology that uses thermal conductive heating (TCH) elements to directly transfer heat to environmental media. The ISTD/TCH process can be applied at low (<100 °C), moderate (~100 °C) and higher (>100 °C) temperature levels to accomplish the remediation of a wide variety of contaminants, both above and below the water table. ISTD/TCH is the only major in situ thermal remediation (ISTR) technology capable of achieving subsurface target treatment temperatures above the boiling point of water and is effective at virtually any depth in almost any media. TCH works in tight soils, clay layers, and soils with wide heterogeneity in permeability or moisture content that are impacted by a broad range of volatile and semi-volatile organic contaminants.

History 
ISTD using TCH was developed by Shell Oil Co. in the late 1980s and grew out of research and development for enhanced oil recovery. During the mid-1990s Shell Oil Company commercialized ISTD with an investment of over $30 million.

Method of operation 
Thermal conductive heating is the application of heat to subsurface soils through conductive heat transfer.  The source of the heat is applied via electric or gas powered thermal wells.  Thermal wells are inserted vertically, or horizontally, in an array within the soil.  Heat flows from the heating elements by conduction.  The heating process causes contaminants to be vaporized or destroyed by means of:
 evaporation
 steam stripping
 hydrolysis
 oxidation
 pyrolysis

Vaporized contaminants are collected from vapor extraction wells and containerized for removal or recycling.

See also
 Soil vapor extraction
 thermal blanket

References

Pollution control technologies
Soil contamination
Waste treatment technology
Karwar Airport. Karwar Airport is a proposed airport and will be built by the Indian Navy at Alageri village near Ankola in Karnataka. The naval air station is expected to start functioning in 2025.

The Airports Authority of India (AAI) will operate a civil enclave at the naval air base which is part of the Navy's Rs 10,000 crore Phase 2 of Project Seabird.

Naval air station 

The Naval Air Station Karwar is being built on 1,328 acres primarily to cater to the Navy's large, ship-based helicopter units and Dornier 228 aircraft that will be stationed at the base. The Indian Navy's Boeing P-8I, advanced maritime surveillance aircraft is also expected to be stationed at Ankola.

The commissioning of a naval air station at Karwar will decongest INS Hansa at the nearby Dabolim Airport which is a front line Air Station that is highly congested with both operational and training flying. The resulting restrictions on civil commercial air traffic has met with opposition from civilian quarters since Goa is a popular tourist destination in India

In early 2007, there were reports of a concerted move by the Navy, the AAI, and the state of Karnataka to extend the runway planned at the naval base near Ankola to 2,500 metres (8,200 ft) to accommodate Airbus A320s and to acquire 75 extra hectares for this purpose. However, there have been no corresponding plans announced so far to relocate flight training from Dabolim to this airport or any other more convenient place.

Civilian Use 
Navy had initially planned to construct a 2,000-metre long runway for the naval air station. The Karnataka State Government approached the Ministry of Defence (MoD) to use the air station for civil operations. The MoD approved of the proposal and asked the State government to facilitate the extension of the runway by another 1000 metres to a total of 3000 meters.

The AAI had carried out an inspection of the site at the request of the Karnataka Government in 2006. It had given suggestions regarding orientation, location and extension of the proposed runway to 2,500 metres and also of its land requirements of an additional 75 hectares.
Accordingly, in 2019, the district administration began acquiring 40 acres for extension of the runway and for the terminal building. The State Government has requested the Central Government to bear the cost of acquisition of this additional land, estimated to be Rs. 20 crores.

See also
 INS Kadamba
 List of airports in Karnataka

References 

Airports in Karnataka
Proposed airports in Karnataka
Buildings and structures in Uttara Kannada district
Transport in Uttara Kannada district
Birge–Sponer method. In molecular spectroscopy, the Birge–Sponer method or Birge–Sponer plot is a way to calculate the dissociation energy of a molecule. This method takes its name from Raymond Thayer Birge and Hertha Sponer, the two physical chemists that developed it.
A detailed example may be found here.

Description

By observing transitions between as many vibrational energy levels as possible, for example through electronic or infrared spectroscopy, the difference between the energy levels,  can be calculated. This sum will have a maximum at , representing the point of bond dissociation; summing over all the differences up to this point gives the total energy required to dissociate the molecule, i.e. to promote it from the ground state to an unbound state. This can be written:

where  is the dissociation energy. If a Morse potential is assumed, plotting  against  should give a straight line, from which it is easy to extract  from the intercept with the x-axis. In practice, such plots often give curves because of unaccounted anharmonicity in the potential; furthermore, the low population of the higher states (or the Franck–Condon principle) makes it difficult to experimentally obtain data at high values of . Thus the extrapolation can be inaccurate and only an upper limit for the value of the dissociation energy can be obtained.

References 

Spectroscopy
Brown Rebel. The Rebel was an American high-wing, V-tailed, single-seat glider that was created by Bob Brown in 1957.

Design and development
The Rebel was created by joining the wing from the Lyle Maxey designed Jennie Mae to a fuselage from the Irv Prue designed Prue 215.  It had a wingspan of with an aspect ratio of 23.8.  The airfoil was a NACA 65 (3)-518 and achieved a best L/D of 37.5. Only one was built and it is no longer listed on the Federal Aviation Administration registry.

Operational history
The Rebel was flown extensively in competitions. At a contest in Tulsa, OK over Memorial Day weekend in 1959, Brown placed 3rd flying the Rebel. Brown flew it in the 1959 US National Soaring Championships at Elmira, NY, placing 24th. At the Southwestern and Texas Soaring Championships held in September 1959 in Grand Prairie, TX, Brown placed 2nd flying the Rebel. In 1959, Brown and the Rebel made four flights over , two of which were over .

Over Memorial Day weekend in 1960, Brown took first place in a contest at Fort Rucker, AL. Brown then flew the Rebel to 33rd place in the US National Soaring Championships held at Odessa, TX. Over Labor Day weekend 1960, Brown and the Rebel took first place in a contest at Marietta, GA.

In 1961, Brown flew the Rebel in the National Soaring Championships held at Wichita, KS.  He placed 21st.

By 1964, Brown had the Rebel up for sale.

Specifications (Rebel)

See also

References

1950s United States sailplanes
Homebuilt aircraft
Aircraft first flown in 1957
V-tail aircraft