omniomni/omni-engineering huggingface dataset:
Maitland B. Bleecker. Maitland B. Bleecker (25 January 1903 – 19 October 2002) was an American inventor and author who was instrumental in modern helicopter design. Bleecker also holds a number of other patents, one including a boat launching device and another for a reaction propulsion device.

Biography
Bleecker graduated from University of Michigan in 1924 and secured a position with National Advisory Committee for Aeronautics at Langley Field, VA.  He then joined Curtiss Aeroplane Division where he developed and constructed a prototype helicopter known as the Curtiss-Bleecker SX-5-1 Helicopter at Garden City, NY.  This helicopter flew successfully, but the project was abandoned because of The Great Depression.

In 1937 he founded Atlantic Casting and Engineering Corporation and retired in 1945.

Upon his retirement, he purchased  of land near West Milford, N.J. where he constructed Lake Sonoma, started a trout hatchery, and operated the Tapawingo Fishing Preserve. This area is now a part of Norvin Green State Forest.

References

External links
 Popular Science, Sept 1930 P. 20
 Modern Mechanix Magazine, Sept. 1930, Pg. 170
 Time Magazine, Nov. 7 1927
 Suburban Trends
 Maitland B. Bleecker Patents

American aircraft designers
American aerospace engineers
University of Michigan College of Engineering alumni
1903 births
2002 deaths
20th-century American engineers
20th-century American inventors
Melecio Arranz. Melecio Arranz y Alivin (May 24, 1888 – April 24, 1966) was a Filipino politician and engineer, born in Alcala, Cagayan.

Early life and career
He obtained his degree of Bachelor of Arts from Colegio de San Albero Magno and his Bachelor of Science in Civil Engineering from the University of Santo Tomas. His government service began in 1914 when he worked as Junior Assistant Engineer at the Bureau of Public Works and became District Engineer of Bataan and Rizal (1919) and later was promoted as Supervising District Engineer.

Political career
As Senator, he was elected in 1928 representing the First Senatorial District comprising Cagayan, Isabela, Ilocos Norte, Ilocos Sur and Abra. Reelected in 1934, 1941 and 1946, his term ended in 1951. He was the Majority leader of the Senate of the Philippines from 1945 to 1946. He was floor leader and Chairman of the Committee on Public Works and Communications (1936) and floor leader and Senate President Pro-Tempore (1946–1949).

Arranz also served in the Philippine Council of State in 1934 and in the Japanese-sponsored Preparatory Committee on Philippine Independence, which laid out the establishment of the Second Philippine Republic in 1943.

In 1947, he was appointed Chief Delegate of the Philippines to the United Nations Commission on Korea.

Personal life and death
Arranz was married to Consuelo Arguelles and had five children. He died on April 24, 1966.

References

1888 births
1966 deaths
People from Cagayan
Presidents pro tempore of the Senate of the Philippines
Majority leaders of the Senate of the Philippines
Senators of the 2nd Congress of the Philippines
Senators of the 1st Congress of the Philippines
Senators of the 1st Congress of the Commonwealth of the Philippines
Senators of the 10th Philippine Legislature
Senators of the 9th Philippine Legislature
Senators of the 8th Philippine Legislature
Liberal Party (Philippines) politicians
University of Santo Tomas alumni
Nacionalista Party politicians
20th-century Filipino engineers
Members of the National Assembly (Second Philippine Republic)
Members of the Senate of the Philippines from the 1st district
Skotfoss Bruk. Skotfoss Bruk was a paper mill located in Skotfoss, Skien, Norway. The mill was part of the Union Co., founded in 1890. It closed production on 31 December 1986.

The first electric industrial railway in Norway opened in 1892 at Skotfoss Bruk.

References

Manufacturing companies established in 1890
Manufacturing companies disestablished in 1986
Buildings and structures in Skien
Pulp and paper mills in Norway
1890 establishments in Norway
1986 disestablishments in Norway
Hemispherical omnidirectional gimbaled wheel. A hemispherical omnidirectional gimbaled wheel (HOG wheel) is a drive system utilizing a hemisphere spinning continuously on its axis.  

When the hemisphere is horizontal, it is like a spinning top, and applies negligible torque to its contact point on the ground.  When tipped on edge, however, it pulls like a traditional circular wheel.  The torque can be quickly vectored in any direction by tilting the hemisphere side-to-side and/or front-to-back.  For example, if the hemisphere is spinning clockwise, tilting it to the right will "pull" the vehicle forward, tilting it to the left will "push" the vehicle backward, and front-to-back tilt will push left or right.  Notably, the torque is proportional to the hemisphere's tilt, providing performance similar to an infinite gear ratio, but without any gears.

One limitation of the HOG wheel is its reliance on a single point of contact with the ground.  This requires a flat, hard surface, especially for small robotic vehicles.

The October 1938 issue of Mechanics and Handicraft magazine featured a concept illustration of a HOG drive automobile called a "Hemisphere Drive Speedster." A personal vehicle utilizing a HOG drive made from Chinese woks won the 1988 Toyota Olympic Ideas competition.  More recently, it has seen use in robotics, where it has also been called a "singularity drive" due to the lack of motion (singularity) when the hemisphere is vertical.

References

See also 
 Odometry

Wheels
GippsAero GA10. The GippsAero GA10 Airvan, marketed as the Airvan 10, is a 10-seat, turbo prop, single-engined utility aircraft currently being developed by GippsAero (formerly Gippsland Aeronautics) of Victoria, Australia.

Development

Its 20-minute first flight was completed in May 2012. In mid-2015, the aircraft was planned to be certified in 2015, but later in the year no schedule was claimed.
It was certificated by the Australian Civil Aviation Safety Authority on 19 May 2017, as well as the American Federal Aviation Administration.

In January 2018, two GA10s were flying: the prototype and the first production aircraft, which GippsAero hopes to deliver in the second half of 2018.

On 4 June 2018, during flight tests supported by the National Test Pilot School from the Mojave Air & Space Port in southern California, a GA10 crashed in the Mojave Desert.
The two pilots parachuted safely from about  above ground.

On 24 August 2018, the first customer for GA10 Airvan was announced to be Major Blue Air, Botswana.
Its unit cost in 2018 was $1.7 Million

Design
After successful development of the eight-seat GA8 Airvan piston-engined aircraft, the design has been stretched and re-engined with a turboprop engine to increase seating and payload capacity, resulting in the GA10. With many piston-engined GA8 aircraft being operated in remote areas, the JetA/JetA1-powered GA10 is intended to appeal to general aviation customers.

The GA10 retains the aerodynamic design of the GA8 and the intent is to retain as many current production parts as possible. A design requirement is for a five-hour endurance with eight occupants (including pilot), and a maximum fuel load of 550 litres. Similarly to the GA8, a STOL kit will be developed for the GA10.

The GA10 should be a capable intelligence, surveillance and reconnaissance (ISR) platform, after the piston GA8, carrying an electro-optical/infrared sensor (EO/IR) ball in a modified underside baggage bay for an unobstructed 360° view.

Specifications

See also

References

External links

 Gippsland Aeronautics Official Site
 

GA10
Single-engined tractor aircraft
2010s Australian civil utility aircraft
Aircraft first flown in 2012
High-wing aircraft
Aircraft with fixed tricycle landing gear
Single-engined turboprop aircraft
DIN 4420. DIN 4420 refers to a series of DIN standards dedicated to working and protection scaffolds.  The standard is divided in the following parts:

 DIN 4420-1 - Service and working scaffolds - Part 1: Service scaffolds - Performance requirements, general design, structural design
 DIN 4420-2 - Working and protection scaffolds – Ladder scaffolds
 DIN 4420-3 - Service and working scaffolds - Part 3: Selected types of scaffolding constructions and their basic versions
 DIN 4420-4 - Working and protection scaffolds – Prefabricated scaffolds – Materials, components, dimensions, loadbearing capacity and safety requirements

References

4420
Southwestern Division. The United States Army Corps of Engineers Southwestern Division (SWD) is one of the eight permanent divisions of the Army organization, providing civil works and military water resource services and infrastructure. It also supports economically viable and environmentally sustainable watershed management and water resources development in Texas, Arkansas, Oklahoma, Louisiana and New Mexico.

The Southwestern Division (SWD) is headquartered in Dallas, Texas, and has been providing service to the region since 1937. The Division was originally located in Little Rock, Arkansas, but in 1941 moved to its current location in Dallas. Its territory stretches from Mexico to Kansas, and covers all or part of seven states. The Southwestern Division civil works encompass  of public land and water. The military works include 10 Army installations and 11 Air Force installations within the SWD boundaries. And SWD's recreation areas are the most visited in the Corps, with more than  of shoreline and 1,172 recreation sites.

The Division Commander is directly responsible to the Chief of Engineers. The SWD Commander directs and supervises the individual District Commanders.  The current SWD commander is Col. George H. Walter.

SWD duties include:
 Preparing engineering studies and design.
 Constructing, operating, and maintaining flood control and river and harbor facilities and installations.
 Administering the laws on civil works activities.
 Acquiring, managing, and disposing of real estate.
 Mobilization support of military, natural disaster, and national emergency operations.

Districts 
The Division's four districts are headquartered in:
 Little Rock, Arkansas
 Tulsa, Oklahoma
 Galveston, Texas
 Fort Worth, Texas

References

External links
 Southwestern Division

Divisions of the United States Army Corps of Engineers
Slip ratio (gas–liquid flow). Slip ratio (or velocity ratio) in gas–liquid (two-phase) flow, is defined as the ratio of the velocity of the gas phase to the velocity of the liquid phase.

In the homogeneous model of two-phase flow, the slip ratio is by definition assumed to be unity (no slip). It is however experimentally observed that the velocity of the gas and liquid phases can be significantly different, depending on the flow pattern (e.g. plug flow, annular flow, bubble flow, stratified flow, slug flow, churn flow). The models that account for the existence of the slip are called "separated flow models".

The following identities can be written using the interrelated definitions:

where:
 S – slip ratio, dimensionless
 indices G and L refer to the gas and the liquid phase, respectively
 u – velocity, m/s
 U – superficial velocity, m/s
  – void fraction, dimensionless
 ρ – density of a phase, kg/m3
 x – steam quality, dimensionless.

Correlations for the slip ratio 
There are a number of correlations for slip ratio.

For homogeneous flow, S = 1 (i.e. there is no slip).

The Chisholm correlation is:

The Chisholm correlation is based on application of the simple annular flow model and equates the frictional pressure drops in the liquid and the gas phase.

The slip ratio for two-phase cross-flow horizontal tube bundles may be determined using the following correlation:

   where the Richardson and capillary numbers are defined as  and .

For enhanced surfaces bundles the slip ratio can be defined as:

Where:
 S – slip ratio, dimensionless
 P – tube centerline pitch
 D – tube diameter
 Subscript – liquid phase
 Subscript – gas phase
 g– gravitational acceleration
 – minimum distance between the tubes
 G-mass flux (mass flow per unit area)
 – dynamic viscosity
 – surface tension
 – thermodynamic quality
 – void fraction

References 

Fluid dynamics
30th Launch Group. The 30th Launch Group was a  United States Air Force unit, and was assigned to the 30th Space Wing, Vandenberg AFB, California.

Overview
The 30th Launch Group was responsible for booster and satellite technical oversight and launch processing activities to include launch, integration and test operations. The group consisted of an integrated military, civilian and contractor team with more than 250 personnel directly supporting operations from the Western Range.

Lineage
 Established as 30th Launch Group on 28 Oct 2003
 Activated on 1 Dec 2003
 Inactivated on 20 July 2018

Assignments
 30th Space Wing, 1 Dec 2003 – 20 Jul 2018

Units
 2d Space Launch Squadron, 1 Dec 2003 – 31 Oct 2005
 4th Space Launch Squadron, 1 Dec 2003 – present
 1st Air and Space Test Squadron, 1 Dec 2003 – present

Missiles
 Titan II, 2003
 Atlas II, 2003
 Titan IV, 2003-2005
 Delta II, 2003-2009
 Minotaur, 2003 – present
 Pegasus, 2003 – present
 Atlas V, 2003 – present
 Delta IV, 2003 – present

References

 30th Launch Group Factsheet

Space groups of the United States Air Force
Space access
Boundary estimation in EIT. Boundary estimation in EIT is the term used in the field of electrical impedance tomography, if the inverse problem is the estimation of boundary instead of the conductivity distribution inside an object domain.

Theory

Electrical impedance tomography (EIT) is a non-invasive imaging modality in which a cross sectional image of the conductivity distribution inside an object can be obtained by injecting a set of current patterns and measuring boundary voltages across the electrodes attached to the surface of the object. If the conductivity values of all the regions inside the object are assumed to be known a priori then the inverse problem in EIT becomes the estimation of shape, size and location of the underlying regions. Such a problem is often known as the boundary estimation problem in EIT.

Categories of boundary estimation in EIT
 
The boundary estimation problem in EIT can be broadly categorized into two classes according to the topology of the boundary to be estimated: closed boundary problems, in which the anomalies are enclosed by a background substance, and the open boundary problems in which the domain is divided into two or more disjoint regions which are separated by an open boundary.

Several closed boundary estimation approaches have been devised in the literature, In one of the most popular techniques, the boundaries of the regions enclosed inside a domain are considered to be smooth enough so that they can be expressed using coefficients of truncated Fourier series.

The open boundaries, usually referred to as the interface boundaries, are often represented using front points spaced discretely along the interface.

Applications

The applications of EIT boundary estimation are in the field of medical imaging as well as the monitoring of the industrial processes.

EIT boundary Estimation applied to medical imaging 

The conductivity estimation using EIT is a nonlinear ill-posed problem. In medical imaging we are often interested in the estimation of organ boundaries rather than the conductivity distribution inside the human body. The poor spatial resolution of EIT makes it difficult to estimate the organ boundaries, thus undermining its anatomical significance. If the conductivity values inside a specific region of the human body, such as that of thorax region, are assumed to be known a priori then the inverse problem in EIT becomes the estimation of shape, size and location of the internal organs. It consequently leads to a much lesser ill-posed problem and significantly reduces the dimension of the solution space,.

EIT boundary Estimation applied to industrial process monitoring 

The applications of EIT in the process industry include monitoring the multi-phase flow in the process pipelines  sedimentation monitoring, etc.

References

Tomography
Ichari Dam. The Ichari Dam is a concrete gravity dam on the Tons River  north of Dakpathar in Uttarakhand, India. The primary purpose of the dam is hydroelectric power production and it is a run-of-the-river-type. It was completed in 1972. The dam diverts water to the Chibro Power Station (240 MW) which is then returned to the Tons River before being fed to the Khodri Power Station (120 MW).

Design and operation
The dam is a  tall and  long concrete gravity type with a structural volume of . The dam's spillway is located across its crest and is controlled by seven floodgates. It has a maximum discharge capacity of . The dam's reservoir has a  capacity, of which  is active (or "useful") capacity. The surface area of the reservoir is .

Chibro Power Plant
Adjacent to the dam and on its left bank, water is diverted into a  head-race tunnel which leads south to the underground power station at . There, the water powers four 60 MW Francis turbine-generators. The design hydraulic head of the station is  and its design discharge is . The plant was commissioned in 1975 and was the first power plant built underground in Northern India.
Made by

Khodri Power Plant
Water discharged from the Chibro Power Plant is returned into the Tons River just  upstream of the intake for the Khodri Power Station. Water enters the intake and then travels south down a  head-race tunnel which leads to the power station on the Yamuna River at . There, the water powers four 30 MW Francis turbine-generators before being discharged into a tail-race channel behind the Dakpathar Barrage. The design hydraulic head of the station is  and its design discharge is . The plant was commissioned in January 1984.

See also

List of power stations in India

References

Dams completed in 1972
Dams in Uttarakhand
Gravity dams
Dams on the Yamuna River
1972 establishments in Uttar Pradesh
Energy infrastructure completed in 1984
Energy infrastructure completed in 1975
Run-of-the-river power stations
Underground power stations
20th-century architecture in India
W. H. J. Grout. William Henry James Grout (1839–1915) was a pioneering inventor and manufacturer of bicycles.

Grout grew up in Hackney and established the Tension Bicycle company in Stoke Newington.  He patented the Grout Tension Bicycle in 1870 which introduced several innovations including hollow forks to save weight, rubber tyres for a better ride and adjustable spokes which could be tensioned to align the wheel.  He also devised a portable version of a Ordinary bicycle penny-farthing, whose front wheel could be dismantled into four sections for carrying.

References

19th-century British inventors
19th-century English engineers
1839 births
1915 deaths

Sustainable transport pioneers
David Harrison (chemical engineer). Sir David Harrison  FRSCM (3 May 1930 – 27 March 2023) was a British chemical engineer and academic. He was vice-chancellor of the University of Keele from 1979 to 1984, vice-chancellor of the University of Exeter from 1984 to 1994, master of Selwyn College, Cambridge, from 1994 to 2000, and pro-vice chancellor of the University of Cambridge in 1997.

Harrison was educated at Bede School, Sunderland, Clacton County High School and Selwyn College, Cambridge, reading natural sciences (chemistry), before receiving a PhD in physical chemistry. He joined the newly formed Chemical Engineering Department doing extensive research into Fluidisation which resulted in three books, all written with his close friend Prof John Davidson. He taught at Cambridge University until 1979, becoming a fellow of Selwyn in 1957 and its Senior Tutor.

Harrison was elected a Fellow of the Royal Academy of Engineering in 1987.

Outside academia, he was chairman of the Government's Advisory Committee on the safety of nuclear installations. He chaired the Councils of both Exeter and Ely Cathedrals, he was a governor of numerous schools and Director of the Salters Livery Company. Between 1996 and 2005 he was Chairman of the Council of the Royal School of Church Music.

Harrison was received a CBE in 1990 and was knighted in 1997. In 1962 he married Sheila Rachel Debes and they had a son and daughter and one son deceased.

Harrison died on 27 March 2023, at the age of 92.

Harrison House and Harrison Drive in Homerton College, University of Cambridge are named after Harrison, marking his service as chair of the Trustees of Homerton College until 2010 when it received its Royal Charter and became self-governing. The Harrison Building is named after him at Exeter University. The SCR at Selwyn College is named the Harrison Room after him.

References

1930 births
2023 deaths
People educated at Bede Grammar School for Boys
Vice-chancellors of Keele University
Vice-chancellors of the University of Exeter
Masters of Selwyn College, Cambridge
Fellows of Selwyn College, Cambridge
Alumni of Selwyn College, Cambridge
Fellows of the Royal Academy of Engineering
Commanders of the Order of the British Empire
Knights Bachelor
Parallel parking problem. The parallel parking problem is a motion planning problem in control theory and mechanics to determine the path a car must take to parallel park into a parking space.  The front wheels of a car are permitted to turn, but the rear wheels must stay aligned.  When a car is initially adjacent to a parking space, to move into the space it would need to move in a direction perpendicular to the allowed path of motion of the rear wheels.  The admissible motions of the car in its configuration space are an example of a nonholonomic system.

See also
 Automatic parking
 Bicycle and motorcycle dynamics
 Falling cat problem
 Moving sofa problem

References
 .
 .

Control theory
Stone-coated metal roofing. A stone coated metal roof is a roof made from steel or some other metal; the metal is then coated with stone chips and attached to the steel with an acrylic film. The goal is a more durable roof that still retains the aesthetic advantages of a more traditional roofing material

History	
Stone coated metal roofing was refined during and after World War II in the United Kingdom, when the government requested materials that would protect corrugated steel roofs from the harsh climate. A coating of bitumen and subsequent covering by sand, stone or other materials proved effective at protecting the metal roofs and serving as camouflage against potential attack.

In 1954, L.J. Fisher, an industrialist from New Zealand, secured the rights to produce stone-coated metal roofing outside Great Britain.  The company he founded, AHI Roofing, operates the largest metal roofing factory in the world, and has continued to make changes to the metal roofing product.

Advantages of stone roofs 

 Appearance: Stone Roofs have a beautiful appearance and therefore are well recommended by architects for attractive look and great designs.
 Strength: Stone Roofs are strong, durable and can hold out much more than traditional roofs.
 Water Resistance: They are water resistant and can hence withstand tough weather changes.

References

Roofs