omniomni/omni-engineering huggingface dataset:
Fréedericksz transition. The Fréedericksz transition is a phase transition in liquid crystals produced when a sufficiently strong electric or magnetic field is applied to a liquid crystal in an undistorted state. Below a certain field threshold the director remains undistorted. As the field value is gradually increased from this threshold, the director begins to twist until it is aligned with the field. In this fashion the Fréedericksz transition can occur in three different configurations known as the twist, bend, and splay geometries. The phase transition was first observed by Fréedericksz and Repiewa in 1927. In this first experiment of theirs, one of the walls of the cell was concave so as to produce a variation in thickness along the cell. The phase transition is named in honor of the Russian physicist Vsevolod Frederiks.

Derivation

Twist geometry
If a nematic liquid crystal that is confined between two parallel plates that induce a planar anchoring is placed in a sufficiently high constant electric field then the director will be distorted. If under zero field the director aligns along the x-axis then upon application of an electric field along the y-axis the director will be given by:

Under this arrangement the distortion free energy density becomes:

The total energy per unit volume stored in the distortion and the electric field is given by:

The free energy per unit area is then:

Minimizing this using calculus of variations gives:

Rewriting this in terms of  and  where  is the separation distance between the two plates results in the equation simplifying to:

By multiplying both sides of the differential equation by  this equation can be simplified further as follows:

The value  is the value of  when . Substituting  and  into the equation above and integrating with respect to  from 0 to 1 gives:

The value K(k) is the complete elliptic integral of the first kind. By noting that  one finally obtains the threshold electric field .

As a result, by measuring the threshold electric field one can effectively measure the twist Frank constant so long as the anisotropy in the electric susceptibility and plate separation is known.

Notes

References

Liquid crystals
Phase transitions
Ganges Barrage. The Ganges Barrage, officially named as the Lav Khush Barrage, is a bridge across the Ganges river at Azad Nagar-Nawabganj near Kanpur's Marine drive Atal Ghat in Kanpur.

Construction started in 1995 and it was inaugurated in May 2000. The total length is . The bridge serves as a four-lane highway bypass for NH 91. It serves as an entry point to the under-construction satellite township known as Trans Ganga City.

Proposed developments

Botanical garden
The layout plan of John Forbes Botanical Garden, prepared by a Delhi-based architect, was approved by the Kanpur Development Authority in 2014. There would be other attractions for entertainment and resources to improve the knowledge of children. There would be a cinema house and an artificial lake. Water museum would be another attraction while trees would illuminate in the evening. For cultural programme a well equipped platform is also proposed. There would be a shopping-cum-kid museum block, food court, game, entertainment zone and provision of two banquet halls.

Trans Ganga city

The Trans Ganga City project, billed as a modern and clean-green city, would be developed by Uttar Pradesh State Industrial Development Corporation. Under the project, along with industrial and residential areas, commercial and institutional areas would be developed. A housing society comprising exhibition centre, multiplex, mega mall and multi-storied residential complexes are proposed. The industries in the enclave would be pollution free and it would be zero discharge area, so that it does not cause adverse impact on the ecology and Ganga river.
 
A high speed train was proposed between Ganga Barrage and Lucknow which will give relief for daily commuters between two cities.

Awadh Expressway
A new expressway between Kanpur and Lucknow will be connected to Ganga Barrage. It would be six expandable upto 8 lane access controlled expressway.

Amusement park
The Kanpur Development Authority has planned to develop an amusement park in the city near Ganga Barrage. On the lines of Delhi Daat, it is also planning to develop a 'haat' inside the park where only handicraft items would be sold. The park will consist of open-air amphitheatre, drive-in cinema, swings for kids, lake for boating and cafeteria etc.

Events
There have been cases of people committing suicide by jumping off the Barrage bridge.

Panoramic view

References

Buildings and structures in Kanpur
Barrages in India
Weirs
Dams in Uttar Pradesh
Bridges over the Ganges
Dams completed in 2000
2000 establishments in Uttar Pradesh
Transport in Kanpur
Salmson B.9. The Salmson B.9 was a French designed, nine-cylinder, water-cooled radial aero engine that was produced under license in Britain. The engine was produced between August 1914 and December 1918. The French version was designated 9B with a slightly increased capacity variant known as the R.9 or 9R. A further variant known as the M.9 or 9M unusually drove the propeller through a 90-degree gear train.

Variants
Salmson B.9 (Salmson 9B)
140 horsepower (104 kW)
Salmson M.9 (Salmson 9M)
120 horsepower (89 kW), 90-degree propeller drive
Salmson R.9 (Salmson 9R)
160 horsepower (119 kW, increased bore to 140 mm.

Applications
Salmson B.9
Farman F.27
Short Admiralty Type 135
Short Type C
Short 830
Voisin LA.S
Salmson M.9 
Blackburn Type L
Breguet U2
Voisin LA
Salmson R.9
Farman F.27

Engines on display
A watercooled, nine-cylinder Salmson engine is on public display at the London Science Museum.

Specifications (B.9)

See also

References

Notes

Bibliography

 Lumsden, Alec. British Piston Engines and their Aircraft. Marlborough, Wiltshire: Airlife Publishing, 2003. .

1910s aircraft piston engines
Salmson aircraft engines
Water-cooled radial engines
Curtiss-Wright CW-3 Duckling. The Curtiss-Wright CW-3 Duckling (sometimes called the Teal) was an American two-seat amphibian flying-boat developed by Curtiss-Wright from the CW-1 Junior.

Development
The Duckling was a modification of the CW-1 Junior. The fuselage had a plywood V-shaped underside added and the addition of strut-mounted pontoons. The engine was mounted above the wing driving a pusher propeller. Only three aircraft were built, all powered by different engines. The type was not developed due to lack of funds.

Variants
CW-3
Prototype powered by a 90hp (67kW) Velie M-5 radial engine, one built.
CW-3L
Variant powered by a 90hp (67kW) Lambert radial engine, one built.
CW-3W
Variant powered by a 90hp (67kW) Warner Scarab radial engine, one built.

Specifications (CL-3W)

See also

References

Citations

Bibliography

Flying boats
Duckling
1930s United States civil utility aircraft
Single-engined pusher aircraft
Parasol-wing aircraft
Amphibious aircraft
Aircraft first flown in 1931
Aircraft with retractable conventional landing gear
Single-engined piston aircraft
DAR 1. The DAR 1 Peperuda (butterfly) was a 1920s Bulgarian two-seat touring or trainer biplane, designed by Hermann Winter and built by the DAR – Drjavna Aeroplane Rаbotilnitsa – State Aircraft Workshops.

Design and development
The aircraft was a conventional two-seat single-bay biplane with a fixed tailskid landing gear, powered by a 60 hp (45 kW) Walter NZ radial engine. Further development resulted in the DAR 1A, which was powered by an 85 hp Walter Vega engine, eight DAR 1As being produced.

After the maiden flight and successful flight tests the DAR 1 was put into production in 1926. Production DAR 1A aircraft were delivered from 1928.

Operational history
The twelve DAR 1 and eight DAR 1A aircraft were used by the Bulgarian Air Force at the Kazanlak Air School, for primary training and the Yato fighter squadron for continuation training, from 1926 to the early 1940s. Some DAR 1A aircraft were also used by the Civil Air Service as glider tugs.

Variants
DAR 1
Initial production variant with a 60hp (45kW) Walter NZ 60 radial engine, 12 built.
DAR 1A
Variant powered by an 85hp (63kW) Walter Vega engine, eight built plus some upgraded from DAR 1s.

Operators

 Bulgarian Air Force
Kazanlak Air School
Yato Fighter Squadron
Bulgarian Civil Air Service

Specifications (DAR 1)

See also

References

Bibliography

Insignia Issue 8 March/April 1998 pp. 132–135
Air Power of the Kingdom of Bulgaria Part III

External links

 DAR DAR-1 Peperuda

DAR 01
1920s Bulgarian military trainer aircraft
Single-engined tractor aircraft
Biplanes
Douglas XT3D. The Douglas XT3D was an American three-seat torpedo bomber biplane developed by the Douglas Aircraft Company to meet a United States Navy requirement.

Development

The XT3D torpedo bomber (BuNo 8730) was first flown in 1931, it has been described as a large and ugly aircraft. Of metal construction with a fabric covering the XT3D had folding wings and an arrestor hook for carrier operation. With a fixed tailwheel landing gear and powered by a Pratt & Whitney R-1690 Hornet radial engine, the XT3D had three open cockpits, forward for the gunner/bomb-aimer, centre for the pilot, rear for another gunner.

The XT3D failed to meet the Navy's requirements and after tests was returned to Douglas. It was modified with a more powerful Pratt & Whitney XR-1830-54 radial, and wheel fairings and the two rear cockpits were enclosed. Re-designated XT3D-2, it still failed to pass Navy trials and was not ordered into production. The prototype was used by the Navy for the next ten years for general purpose use until it was relegated as an instructional airframe in 1941.

Variants

XT3D-1
Prototype powered by a Pratt & Whitney R-1690 radial, one built.
XT3D-2
Prototype modified including a change to a Pratt & Whitney R-1830 radial.

Operators

United States Navy

Specifications

See also

References

Notes

Bibliography

 

T3D
1930s United States bomber aircraft
Single-engined tractor aircraft
Carrier-based aircraft
Biplanes
Aircraft first flown in 1931
Entwicklungsring Süd. Entwicklungsring Süd (EWR) was a German consortium formed in 1959 to build a Mach 2 Vertical Take-Off Interceptor for the Luftwaffe.

History
The consortium was formed in 1959 by the German aircraft companies Bölkow, Heinkel and Messerschmitt to develop a Mach 2 VTOL interceptor for the German Air Force. In 1964 Heinkel left the consortium and the following year it was formed as a company Entwicklungsring Süd GmbH. A VJ 101C prototype aircraft was built and flown in 1963 although it crashed on its 132nd flight, on 14 September 1964, during a normal horizontal take-off. The accident was found to have been caused by a roll-rate gyro which had been installed with reversed polarity. A modified second prototype flew in 1965 and it was planned to put an improved variant VJ 101D into production, but the development was stopped.

EWR teamed with Boeing, Fairchild, Hiller and Republic Aviation for the Advanced Vertical Strike (AVS).

Products

 EWR VJ 101

References
Notes

Bibliography

 

Defunct aircraft manufacturers of Germany
Heinkel
Messerschmitt
Farman F.110. 

The Farman F.110 was a French two-seat artillery observation biplane designed and built by the Farman Aviation Works.

Development
The F.110 was an effort by Farman to produce an artillery observation aircraft normally supplied to the French military by Breguet. Mainly of aluminium alloy construction it was a biplane design with a tailskid landing gear. Powered by a water-cooled Salmson 9Z radial piston engine which was a cause of drag because of the need for a large radiator box under the nose which compounded the already large frontal area of a radial engine.

The pilot and observer had an open cockpit which had glazed panels in the sides and the floor to give the observer a good view. After a first flight in 1921 the Aéronautique Militaire ordered 175 aircraft but due to a lack of experience in the company with aluminium alloy the F.110 suffered structural problems. After some modification only 50 aircraft were delivered and the type was not developed further. The F.110 only remained in front-line use for just over a year.

In 1927 tests were made with the F.115, a F.110 with its aluminium ribs replaced with wooden ones.

Operators

Aéronautique Militaire

Specifications

References

Notes

Bibliography

1920s French military reconnaissance aircraft
F.110
Biplanes
Single-engined tractor aircraft
Aircraft first flown in 1921
Sikorsky RS. The Sikorsky RS was a designation used by the United States Navy for a number of different Sikorsky twin-engined amphibious flying boats.

Variants
RS-1
Designation for three Sikorsky S-41 flying boats for evaluation.
XRS-2
Designation for two Sikorsky PS-2 flying boats converted as transports.
RS-3
Four Sikorsky PS-3 flying boats converted as transports.
RS-4
Designation for two impressed Sikorsky S-40A flying boats.
RS-5
Designation for two impressed Sikorsky S-41 flying boats.

See also

References

Notes

Bibliography
 

RS
1920s United States military transport aircraft
Flying boats
Amphibious aircraft
Sesquiplanes
Twin piston-engined tractor aircraft
Lockheed Martin ALHTK. Lockheed Martin ALHTK (sometimes spelled Lockheed Martin Air Launched Hit To Kill) was a Lockheed Martin program sponsored by the USAF and Missile Defense Agency. ALHTK mounted the PAC-3 missile on the wing of an F-15 by using an external shell in the shape of a fuel tank to house the PAC-3 missile. As a surface to air missile system the PAC-3 missile has been used successfully in operations in Iraq. The combined ALHTK system engaged ballistic missiles in both the boost and terminal phases of ballistic flight. By 2021 the project had not been adopted and was seemingly dropped by Lockheed, with no further promotional material released concerning the system since 2010.

References

Proposed weapons of the United States
Lockheed Martin
Rovio (robot). Rovio is a Wi-Fi enabled robot manufactured by WowWee which lets its user view what the robot's webcam sees from anywhere in the world. It can be accessed and controlled via an internet connection from any PC, Mac, Cell Phone, Smartphone, PDA or PSP.

The Rovio uses a Kiwi Drive for omnidirectional motion.

References

External links
Rovio page from WowWee web site

Rolling robots
WowWee
2008 robots
Anders Jordahl. Anders Olsen Jordahl (April 4, 1878 – February 18, 1969) was a Norwegian-American engineer,  inventor,  entrepreneur and artist.

Anders Olsen Jordahl was born at Elverum in Hedmark,  Norway. His parents were  Ole Jordahl and Mary (Furer) Jordahl. His father was a schoolteacher. His family was originally from the traditional district of Nordmøre.  In the first years of the new century, Jordahl met the young Swedish civil engineer Ivar Kreuger in the United States. They were both interested in reinforced concrete building design and construction, and worked for a few years in the building industry in the United States. After their work together, both returned to Europe to promote their modern ideas.

In 1907,  Ivar Kreuger acquired the European marketing rights for Kahneisen, a system for reinforced concrete construction invented by Julius Kahn during 1903.  In Germany, Jordahl and Kreuger, formed the company Deutsche Kahneisen Gesellschaft mbH (now Jordahl GmbH) in 1913. Through this company, Jordahl developed and patented an anchor channel for reinforced concrete buildings. He designed a C-shaped profile in 1913  which was moulded into walls and used as reinforcement and connection device at the same time.  This was the first anchor channel ever developed.  The patent for this invention was granted to Jordahl on December 11, 1913.

Jordahl had not only studied building design in America, but also the workings of the stock exchange. He was also a member of the Engineers Club of New York City. He returned to Sweden, and became a famous, (and later infamous) tycoon. For a short period, the two friends ran a restaurant in South Africa. They continued a personal relation during the following years until Kreuger's death in 1932.

Jordahl was an amateur artist, a painter who was also a member of the Salmagundi Club, the oldest artists' club in America. 
Widower of the former Mary Dyas Jordahl, with whom he had a daughter, Helen ("Sunny") LeVaillant, wife of René LeVaillant of Bridgewater, Connecticut.   In 1941, Jordahl moved from Greenwich, Connecticut to Millstone, New Jersey, where he died in 1969.

References

External links

Norwegian company founders
Norwegian engineers
Concrete pioneers
1878 births
1969 deaths
People from Millstone, New Jersey
Norwegian emigrants to the United States
Porter Building. The Porter Building is a historic building listed on the National Register of Historic Places located in the Downtown Historic District of Woodland, California.

History
The building was designed in 1913 by architect W.H. Weeks, architect of many other landmarks in Woodland such as the Woodland Opera House and the Yolo County Courthouse. Construction bids were accepted and Earle L. Younger of San Jose (later a Woodland resident) was the lowest bidder. The building's exterior includes buff-colored Roman brick with elaborately decorated cornice and an arched entrance way that leads into the building's lobby. The building had many modern amenities that were rare for its era, some of which were "firsts" for Woodland, including an electric elevator, steam heating system, and telephone service in each office. The successful completion of this major construction project was of great benefit to Younger, and helped him become one of the more popular commercial builders in Woodland until the 1940s.

Today the building is a part of the Downtown Woodland Historic District. During much of the 2000s, the building was left vacant, but it was announced in December 2009 that a private community college will be moving into the building. A project to retrofit the building to bring it up to date with current safety standards is underway. Changes to the interior of the building will take place in preparation for the classrooms and offices it will house. The current plans are to keep as many preexisting walls as possible. The steam heating system that was originally a luxury for the building is still intact, but a new heating and air conditioning system will also be put in place. The exterior of the building will be restored to its original state in 1913. The architect for the remodeling of the building is Duane Thompson.

References

Buildings and structures in Woodland, California
Commercial buildings on the National Register of Historic Places in California
Commercial buildings completed in 1913
W. H. Weeks buildings
1913 establishments in California
National Register of Historic Places in Yolo County, California
Individually listed contributing properties to historic districts on the National Register in California
OFAB-100-120. The OFAB-100-120 is a small bomb that can be carried on Sukhoi Su-17, Sukhoi Su-25, MiG-29, Su-27, Sukhoi Su-30 and various other aircraft.

Purpose
This bomb is designed to engage lightly armored materiel and military industrial facilities, as well as manpower. It is dropped from altitudes of 500 to 15,000 m at a speed of 500 to 1,150 km/h. This aircraft bomb is effective against personnel in open terrain and motorized infantry at the reserves concentration base either on the march or in battle array. It is filled with fragments and powerful explosive compositions based on TNT/RDX. The design of this aircraft bomb provides for better fragments distribution in the fragments flight area and high density of the fragmentation zone within the lethal range as compared to general-purpose munitions. Aircraft can carry this bomb with a single-point suspension bomb rack or on 14” NATO standard suspension systems, using the corresponding fuze type.

On 26 April 2024, 6 photos surfaced online, taken somewhere in Russia, which appeared to show a crashed  Swift 2 fitted with a single OFAB-100-120 bomb in a centreline type rack. Along with other equipment to allow for it to become a “remotely piloted bomber”. Skyranger had been contacted and said it could be an existing aircraft or one built from a kit worth $55,000.00. Ukraine has previously modified a Aeroprakt A-22 Foxbat into a kamikaze drone.

Technical characteristics
Caliber, 100 kg
Length, 1065mm
Body Diameter, ø273mm
Tail fin span,  345mm
Characteristic time, s	21,10/6
Suspension	 Single/250 mm/14"
Explosive weight, 42 kg
Number of balls	 15 000/6 900
Ball diameter, mm	ø8,75/ø11,9
Bomb weight, 123 kg
Fuze	AVU-ETM; AVU-ET; AVU; AMV-AE2; 2'-12UN-2B; 3,5-12UN-2B

References

Cold War aerial bombs of the Soviet Union
Interactive Robots and Media Lab. The Interactive Robots and Media Lab (IRML) is a research laboratory, originally hosted at the College of IT of the United Arab Emirates University in Al-Ain, Abu Dhabi Emirate, UAE, then moved on to the CSE facilities of New York University Abu Dhabi. Starting January 2013 IRML is expanding, emancipating, and partially commercializing its operations.

The laboratory was founded in September 2007 by Nikolaos Mavridis, a PhD holder from the Massachusetts Institute of Technology, and started operations in February 2008. The main projects underway in the lab (as of December 2009) were two: the Ibn Sina Robot, an android that is able to converse in the Arabic language, as well as the Microsoft-funded FaceBots project, which aimed towards building robots that can sustain long-term relationships with humans through dialogues referencing shared memories and shared friends, while utilizing and depositing social information on the Facebook website. Other projects have started since then; mainly revolving around human-robot interaction, machine perception, and cognitive systems.

The lab has also hosted three international research-centric summer schools, which have a special format: they have a duration of one month, most of the time is spent in collaborative team-work on hands-on research projects, carried out in teams of 3-5 members coming from diverse academic levels (post-doctoral, graduate, undergraduate) and countries of origin. Also, the lab has been involved in other activities related to robotics and interactive media, winning for example the "Best Pipe Inspection Robot Design" at the Schlumberger i-Design course competition, and being involved in activities related to winning the bid and preparation for hosting the World Robot Olympiad (WRO) in Abu Dhabi in 2011.

The lab has been featured in regional as well as international news, on venues such as the BBC, Agence France Press (AFP), The UAE National, Al Jazeera TV etc.

References

External links
 Interactive Robots and Media Lab website
 IRML pavilion at the online robotics expo Expo21xx
 IRML videos channel, YouTube

2007 establishments in the United Arab Emirates
Education in Al Ain
Robotics organizations
Research institutes in the United Arab Emirates
United Arab Emirates University
Sentrigo. Sentrigo was a privately held software company located in Santa Clara, California, USA, until its acquisition in April, 2011 by McAfee.

The company was founded in 2006 by Nathan Shuchami and Slavik Markovich, to address several key challenges in Database security. Specifically, the inability to monitor activity of privileged users and those who have established such credentials through nefarious means, and the difficulty in maintaining a DBMS at the most current patch level. The company's products have expanded to include a broader suite of database security offerings, including database audit and vulnerability assessment as well.

Investors in Sentrigo included: Benchmark Capital, Stata Ventures and Juniper Networks.

References

External links
Official Site
Musings on Database Security by Slavik Markovich
Fuzzing tool helps Oracle DBAs defend against SQL injection

Defunct software companies of the United States
Companies based in Santa Clara, California
Computer security software companies
Software companies of Israel