omniomni/omni-engineering huggingface dataset:
Berkad. A berkad is a water reservoir used in arid areas to collect water during the wet season for use in the dry season. They occur mainly in Somalia and parts of Ethiopia.

Construction and operation 
Berkads were introduced to Somalia in the late 1950s. Most are large rectangular, elongated basins with vertical walls and a capacity of several hundred cubic metres (similar to the size of a swimming pool), sometimes three to four metres deep.  The walls and bottom are often covered in brick and/or coated with cement to reduce water loss due to infiltration to groundwater. At the top, they are open but often covered with canvas to reduce evaporation, or (in poorer villages) with nets on which is laid anything that provides shade (branches, straw, etc.).

Berkads fill naturally in the rainy season. They are placed in locations where small streams form during rain, which are then routed to the berkad with dug trenches. A berkad can sometimes be filled in a few hours. In villages with poor water availability, feed channels can be a few kilometres long, and take the form proper canals coated with cement and/or covered. Berkads are often clustered together.

Water quality 
The inlet of the berkad often has a so-called "catch-pool": a small open reservoir that the water flows through before it enters the large basin. This allows a large part of the transported sediment to settle and other contaminants to be removed. The water in a berkad is nevertheless often turbid and muddy and can pose a health risk. One solution consists of making the tank airtight by constructing a sloping roof over the berkad, often with corrugated sheeting. Water evaporates, condenses on the underside of the roof, runs down into gutters and is collected in a separate metal tank, from which water can be used via handpump. This not only distills the water, but also reduces water losses due to evaporation. Such systems are, however, often too costly for villages to install themselves.

Flow-on-impacts 
The construction of berkads also has disadvantages. In the late 1950s there were only still only a few water points in the Haud, a vast steppe on the border of Somalia and Ethiopia of importance to nomads with their cattle. Nomads roamed according to a traditional seasonal migration and always had to take into account the number of days to walk to the next place where they could water their cattle. Around 2001 there were already around 7000 berkads in the Haud, such that the area is now permanently grazed. This overgrazing leads to ecological degradation and erosion. Settlements also arise around clusters of berkads, increasing population pressure.

References

Environment of Somalia
Hydraulic engineering
Kenny Paterson. Kenneth G. "Kenny" Paterson (born 2 March 1969) is a professor in the Institute of Information Security at ETH Zurich, where he leads the Applied Cryptography Group. Before joining ETH Zurich in April 2019, he was a professor in the Information Security Group at Royal Holloway, University of London and an EPSRC Leadership Fellow. He is a cryptographer with a focus on bridging the gap between theory and practice and recently became the Editor in Chief for the IACR's Journal of Cryptology and a 2017 fellow of the IACR.

Education 

Paterson obtained a BSc in 1990 from the University of Glasgow and a PhD from Royal Holloway, University of London in 1993, both in Mathematics. His doctoral advisor was Fred Piper.

Career 

Paterson was a Royal Society Fellow at Institute for Signal and Information Processing at ETH Zurich from 1993 to 1994. In 1996, he joined Hewlett-Packard Laboratories Bristol. He then joined the Information Security Group at Royal Holloway in 2001, becoming a Reader in 2002 and Professor in 2004. From March 2010 to May 2015, he was an EPSRC Leadership Fellow working on a project entitled "Cryptography: Bridging Theory and Practice". In May 2015, he returned to working as a professor. He became the Editor in Chief for the IACR's Journal of Cryptology.

Research 

Paterson is notable for attacks on the Encapsulating Security Payload in IPSec, the Lucky 13 attack on TLS, attacks on the use of RC4 in TLS and on use of CBC mode in the SSH protocol. He also worked on improved security models proving protocols secure against such attacks.

Awards 

 Distinguished Paper Award for work with Nadhem AlFardan presenting plaintext recovery attacks against DTLS published at NDSS 2012
 Applied Networking Research Prize from the IRTF for work with Nadhem AlFardan on the Lucky 13 attack
 Award for Outstanding Research in Privacy Enhancing Technologies for work with Mihir Bellare and Phil Rogaway on the Security of symmetric encryption against mass surveillance published at CRYPTO 2014.
 Best Paper Award at ACM CCS 2016 for work with Martin Albrecht, Jean Paul Degabriele and Torben Hansen on symmetric encryption in SSH

References 

British cryptographers
1969 births
Living people
Fellows of the Royal Society
Alumni of the University of London
Alumni of the University of Glasgow
Academics of Royal Holloway, University of London
Academic staff of ETH Zurich
Doris Cohen. Doris Cohen was  a twentieth-century American mathematician and aerodynamicist.  She worked at the Langley Memorial Aeronautical Laboratory of the National Advisory Committee for Aeronautics (NACA, a precursor to NASA).  In 1941, a research report she published made her NACA's first female author.

She was married to, and worked with, aerodynamicist R. T. Jones.  With him, she co-founded Vega Instrument Co., a telescope manufacturing company, in 1957.

Bibliography
 An Analysis of the Stability of an Airplane with Free Controls with Robert T. Jones (1941)
 A Graphical Method of Determining Pressure Distribution in Two-dimensional Flow with Robert T. Jones  (1941)
 Theoretical Distribution of Load over a Swept-back Wing (1942)
 A method for determining the camber and twist of a surface to support a given distribution of lift (1942)
 Determination of optimum plan forms for control surfaces with  Robert T. Jones  (1942)
 A Theoretical Investigation of the Rolling Oscillations of an Airplane with Ailerons Free (1944)
 Analytical Investigation of the Stability of an F8F Dropping Model with Automatic Stabilization (1945)
 A method for determining the camber and twist of a surface to support a given distribution of lift, with applications to the load over a sweptback wing (1945)
 The Theoretical Lift of Flat Swept-back Wings at Supersonic Speeds (1948)
 Theoretical Loading at Supersonic Speeds of Flat Swept-back Wings with Interacting Trailing and Leading Edges (1949)
 Formulas and Charts for the Supersonic Lift and Drag of Flat Swept-back Wings with Interacting Leading and Trailing Edges (1950)
 Formulas for the Supersonic Loading, Lift, and Drag of Flat Swept-Back Wings with Leading Edges Behind the Mach Line (1951)
 Theoretical Investigation of the Supersonic Lift and Drag of Thin, Sweptback Wings with Increased Sweep near the Root with Morris D. Friedman (1953)
 Arrangement of Fusiform Bodies to Reduce the Wave Drag at Supersonic Speeds with Morris D Friedman  (1954)

References

External links
 Index to Cohen's works at the NASA

Year of birth missing (living people)
Living people
20th-century American mathematicians
20th-century American women mathematicians
21st-century American women
Libeskind Tower. Libeskind Tower or PwC Tower, also called Il Curvo (The Curved One in English), is a skyscraper completed in 2020 in the city of Milan as part of the CityLife development project. The tower reaches a height of  with 28 floors, and a total floor area of about 76,000 square metres. It is the home for the Milan offices of PricewaterhouseCoopers. The project's designer and namesake is the Polish-American architect Daniel Libeskind.

Description 
The curve of the tower slopes toward its counterparts in the development, the Isozaki and Hadid towers and the Piazza Tre Torri below.

The Renaissance cupola is the basic principle behind Il Curvo's concept. It is reinterpreted through the concave movement of its elevation and it culminates in the crown, both distinctive elements of the project.  The crown, a 40 meter tall structure, not only contains the building’s maintenance, air conditioning, and rainwater recycling system but also doubles as both a viewing platform and an art gallery for the general public. The curved tower's facade is made of sustainable glass which reflects the public space below and vistas around.

Gallery

See also
 List of tallest buildings in Milan
 List of tallest buildings in Italy

References

External links

Skyscrapers in Milan
Skyscraper office buildings in Milan
Buildings and structures completed in 2021
Office buildings completed in 2021
2021 establishments in Italy
21st-century architecture in Italy
Daniel Libeskind buildings
VEF I-11. The VEF I-11 (also called the Irbītis I-11) was a Latvian light aircraft built by VEF.

Design and development 
The I-11 was designed by Kārlis Irbītis in 1936. It was a low-wing monoplane with a two-seat tandem cockpit and fixed conventional landing gear. On the basis of the I-11, Irbītis designed the training fighter I-12.

Operational history 
On June 23, 1936, the I-11 made its maiden flight.

On April 26, 1937, it flew a  flight around Latvia in  hours.

See also 
Related development
 VEF I-12

References

1930s Latvian aircraft
Low-wing aircraft
Single-engined tractor aircraft
VEF aircraft
Diethard Böhme. Diethard Kurt Böhme (born June 1941) is a Canadian chemist, currently a Distinguished Research Professor Emeritus and formerly a Canada Research Chair (2000-2013) at York University.

He was born during World War II to the son of a member of the German consular staff in Boston, Massachusetts. After the war he studied at McGill University in Montreal, Canada, gaining a B.Sc. in 1962 and a Ph.D. in 1965.

During his Ph.D. work he was responsible for the construction of the first quadrupole mass spectrometer in Canada as part of his studies on gas phase ion chemistry. He pursued his interest in the subject as a post-doctoral Research Associate at the University of London and at the Aeronomy Laboratory of the Environmental Sciences Service Administration in Boulder, Colorado. During this period he did pioneering work on the measurement of accurate gas phase acidities of organic molecules using the newly developed flowing afterglow technique.

In 1970 he moved to the new York University in north Toronto to join the Chemistry Department, where he spent the next 35+ years working in a number of areas of chemistry as well as contributing to significant instrumental developments associated with the flowing afterglow technique.

From 2000 to 2013 he was Canada Research Chair in Physical Chemistry (Chemical Mass Spectrometry).

Honours and awards
 1981 Rutherford Memorial Medal for Chemistry by the Royal Society of Canada.
 1998 J.C. Polanyi Award of the Canadian Society for Chemistry
 2002 F.P. Lossing Award in Mass Spectrometry from the Canadian Society for Mass Spectrometry
 2006 G. Herzberg Award of the Canadian Society for Analytical Sciences and Spectroscopy 
 2007 Chemical Institute of Canada Medal 
 Fellow of the Royal Society of Canada

References

1941 births
Living people
Canadian chemists
Academic staff of York University
Fellows of the Royal Society of Canada
CSA PS-38 Tourer. The CSA PS-38 Tourer is a Czech light-sport aircraft under development by Czech Sport Aircraft of Prague, introduced at the AERO Friedrichshafen show in 2014. The aircraft is intended to be supplied complete and ready-to-fly.

Design and development
The PS-38 Tourer was designed for private use for cross-country flying as well as the law enforcement role.

The aircraft was designed to comply with the US light-sport aircraft rules. It features a cantilever high-wing, an enclosed cabin with two-seats-in-side-by-side configuration accessed by doors, fixed tricycle landing gear and a single engine in tractor configuration.

The aircraft is made with an aluminum semi-monocoque structure. Its  span forward-swept wing has an area of  and mounts flaps. The standard engine used is the  Rotax 912ULS four-stroke powerplant. The forward-swept wing provides improved visibility to the pilot in turns.

As of January 2018, the design does not appear on the Federal Aviation Administration's list of approved special light-sport aircraft.

The design also did not appear on the manufacturer's website as offered for sale in February 2017.

Specifications (PS-38 Tourer)

References

PS-38 Tourer
2010s Czech sport aircraft
Light-sport aircraft
Single-engined tractor aircraft
High-wing aircraft
Mass-spring-damper model. The mass-spring-damper model consists of discrete mass nodes distributed throughout an object and interconnected via a network of springs and dampers. This model is well-suited for modelling object with complex material properties such as nonlinearity and viscoelasticity.
Packages such as MATLAB may be used to run simulations of such models. As well as engineering simulation, these systems have applications in computer graphics and computer animation.

Derivation (Single Mass) 
Deriving the equations of motion for this model is usually done by summing the forces on the mass (including any applied external forces :

By rearranging this equation, we can derive the standard form:

 where 

 is the undamped natural frequency and  is the damping ratio. The homogeneous equation for the mass spring system is:

This has the solution:

If  then  is negative, meaning the square root will be imaginary and therefore the solution will have an oscillatory component.

See also
 Numerical methods
 Soft body dynamics#Spring/mass models
 Finite element analysis

References

Classical mechanics
Mechanical vibrations
Configurable mixed-signal IC. Configurable Mixed-signal IC (abbreviated as CMIC) is a category of ICs comprising a matrix of analog and digital blocks which are configurable through programmable (OTP) non-volatile memory. The technology, in combination with its design software and development kits, allows immediate prototyping of custom mixed-signal circuits, as well as the integration of multiple discrete components into a single IC to reduce PCB cost, size and assembly issues.

See also 

 Field-programmable analog array
 Programmable system-on-chip

References

Integrated circuits
Tim Broyd. Professor Tim Broyd is an English civil engineer who was elected the 152nd President of the Institution of Civil Engineers, taking office in November 2016.

Early career
Broyd was born in Carshalton in Surrey, grew up in Wallington and Addington and went to Trinity School, in Shirley. After leaving Trinity School, he went to the University of Birmingham to study science and civil engineering, completing a PhD in 1979.

Professional career
He then began employment at design, engineering and project management consultancy Atkins in Epsom, where he stayed for 20 years, including spells as chief engineer and group research and innovation director. During the early 2000s (2002-2007) he was chief executive at the Construction Industry Research Information Association (CIRIA), before joining the Halcrow Group (later CH2M), where he was group technology, innovation and sustainability director until 2012.

Broyd's interests include digital engineering and infrastructure resilience.

Broyd is now Professor of Built Environment Foresight and Honorary Professor of Civil Engineering at The Bartlett, University College London. He is also a Fellow of the Royal Academy of Engineering and the ICE, a Vice Chairman of the Construction Industry Council and a director of BuildingSMART (UK) Ltd and CEEQUAL Limited.

He was formally elected as the President of the ICE in December 2015, succeeding Sir John Armitt in November 2016.

Family life
He married his wife Ros at St Mary's Church in Addington in 1979, and has lived in Warlingham since the 1990s. He has three children: Edwin, Aiden and Imogen.

References

        
        
        
        
        

English civil engineers
Presidents of the Institution of Civil Engineers
People educated at Trinity School of John Whitgift
Alumni of the University of Birmingham
Living people
Year of birth missing (living people)
Konstantin Petrovich Grigorovich. Konstantin Petrovich Grigorovich (; 18 September 1886 — 15 April 1939) was a metallurgical engineer, founder of the soviet school of electrometallurgy, professor (1921), doctor of technical sciences (1934).

Biography 
Grigorovich Konstantin Petrovich was born 18 September 1886 in Mykolaiv.

In 1913 graduated from Peter the Great St. Petersburg Polytechnic University.

Places of work: from 1913 worked as an engineer at Kirov Plant in St-Petersburg, at the Metallurgical factory of Elektrostal in the city of Elektrostal, Moscow Oblast. From 1920 — head of the electrometallurgical department of the Moscow Mining Academy, from 1931 — technical director of the Spetsstal trust.

His knowledge in the field of metallurgy has proved to be extremely useful during the construction and installation of the soviet ferroalloy factories - in Chelyabinsk (1931), Zestaponi (1934) and in Zaporizhia (1934). In Chelyabinsk he inspected quality of construction works and deployment of several factories: Ferroalloy (July 1931), ferrochrome (1935), electrocorundum (1933), electrode (1934) and abrasive tools (1935).

Field of academic interests: theoretical and practical electrometallurgical production, production of ferroalloys. Grigorovich K. P. — professor (1921), doctor of technical sciences (1934).

Was arrested on 19 September 1938 on false charges for being a member of a counterrevolutionary terrorist organization (included to the list as an active member of counterrevolutionary right-wing Trotskyist, conspirative and spy organization) (931 people on the list) prosecuted by Lavrentiy Beria and Andrey Vyshinsky. Sentenced to death on 14 April 1939. The sentence was executed on 15 April 1939 at the Kommunarka shooting ground. He was rehabilitated on 22 February 1956.

Works 
 Grigorovich K. P. Electrometallurgy of steel. — 1922. — Part 1 : Electric furnaces.
 Grigorovich K. P. Production of steel in electrical furnaces — 1932.
 Grigorovich K. P. Production of bearing steel. — 1932.
 Grigorovich K. P. Chelyabinsk electrometallurgical plant. — 1935.

References

External links 
 Григорович Константин Петрович // «Лица Москвы»

Notes & references 

Political repression in the Soviet Union
1886 births
1939 deaths
Soviet engineers
Kotabe Foundry. Kotabe Foundry is a casting company established over 800 years ago and operated by the 37th successor to the family business.
It is located in Sakuragawa, Ibaraki Prefecture, Japan at the foot of the famous Mount Tsukuba, where sands and clay for the molds are found.

The main products are:
temple bells
fire bells
rainwater bowls etc.

See also 
Early Japanese iron-working techniques
List of oldest companies

References

External links 
Company website
Bells in Japanese temples

12th-century establishments in Japan
Foundries
Companies based in Ibaraki Prefecture
Metal companies of Japan
Caterpillar C175. The Caterpillar C175 is a family of diesel internal combustion engines made by Caterpillar. The engine is 5.3 litres per cylinder in displacement. The cylinder size is  x  bore/stroke. The engine can produce 1500-4800 horsepower at 1800 RPM. The peak torque occurs at an engine speed of 1500 RPM. The engine weighs over ten tonnes. The Cat C175 is often used in locomotives, passenger-class ships and Caterpillar haul trucks like the 793F and 797F.

Sample Applications 

 EMD F125
 Caterpillar 797F
 Stadler Eurolight (including British Rail Class 68)
 Stadler Euro Dual (e.g. as German "Class 159" for European Loc Pool)

See also 
 SEMT Pielstick PA4 series engine
 MTU V4000 engine
 Cummins QSK95
 Mitsubishi SR2-PTA series engine

References and notes 

Caterpillar Inc.
Diesel locomotive engines
Yang Shiming. Yang Shiming or Shih-Ming Yang () was a Chinese thermodynamicist, who was a pioneer in heat transfer in mainland China.

Yang was a standing member of the Executive Committee of the Chinese Society of Engineering Thermophysics and vice chairman of the National Educational Advisory Committee on Thermal Engineering. He had also served on the editorial board of the Journal of Engineering Thermophysics since 1980, the honorary editorial advisory board of the International Journal of Heat and Mass Transfer since 1982, and the executive committee as well as the Scientific Council of the International Centre of Heat and Mass Transfer since 1987.

Early life and education 
Yang fled to Shanghai at age 12. The CPC influenced him when he was studying at a high school, and he joined the party in 1941.

Yang was enrolled at Shanghai Jiao Tong University in 1942. There was a hiatus in his undergraduate life, he backed to the university in 1946 and received his BS degree from there in 1948. Meantime, he successively served as a teacher at a technical school and an engineer at a rubber factory. Afterwards, he received his MS degree from Case Institute of Technology in 1950. Then he became a graduate student with Professor Max Jakob's guidance and obtained his Ph. D. degree from Illinois Institute of Technology in 1953.

Career 
Upon the request of Jakob, Yang joined the Heat Transfer Laboratory of IIT before he returned to Shanghai at the end of 1953. Their concerted effort revealed the Jakob number.

Yang began to teach at Jiao Tong University since 1956, he followed the university's westward moving to Xi'an in the next year. During 1958–85, he was in charge of the thermal engineering section of Xi'an Jiaotong University as an associate professor and then a professor.

Bereavement of wife led to Yang's return to Shanghai Jiao Tong University, where he continued his work until retirement.

Yang made a great contribution to the Chinese thermodynamics education. The textbook Heat Transfer, which he edited, received the National Excellent Textbook Award in 1988.

Family 
Yang's wife died in the 1980s. They had a daughter and a son.

References 

1925 births
2017 deaths
National Chiao Tung University (Shanghai) alumni
Academic staff of Shanghai Jiao Tong University
Thermodynamicists
People from Wuxi
Reinold Geiger. Reinold Geiger (born 10 July 1947) is an Austrian billionaire, and the chairman and executive director of French cosmetics retailer L'Occitane en Provence. On the 2023 Forbes list, he was the 9th richest Austrian with a net worth of US$ 1.4 billion.

Education and career 
Geiger, the son of a carpenter, received a bachelor's degree in engineering from the Swiss Federal Institute of Technology in Zürich, in 1969 and an MBA degree from INSEAD in Fontainebleau (France) in 1976. After graduating he founded several small companies, including a tourism company in London.

In 1978, Geiger founded the AMS Packaging Company in Paris, which specialized in the production of cosmetics packaging. He later sold the company at a profit. In 1994, Geiger started investing millions in the then small cosmetics company L'Occitane and took over the management. He expanded the company into a global group and it was listed on the Hong Kong stock exchange in May 2010. 

In 2021, he stepped down as CEO of L’Occitane but remained chairman and executive director of the company. Geiger owned 70 percent of the company in 2023.

Forbes lists his net worth at USD 2.4 billion, as of February 2024.

Personal life 
Geiger was married to Dominique Maze-Sencier until her death in May 2017. The couple had 3 sons, Maximilien, Nicolas and Adrien. Geiger lives in Geneva, Switzerland. He owns properties in the alps, on the Île de Ré and in Trancoso, Brazil.

References

1947 births
Living people
Austrian billionaires
Austrian businesspeople
Austrian expatriates in Switzerland
ETH Zurich alumni
Businesspeople from Geneva
INSEAD alumni