omniomni/omni-engineering huggingface dataset:
Access structure. Access structures are used in the study of security systems where multiple parties need to work together to obtain a resource. Groups of parties that are granted access are called qualified. In set theoretic terms they are referred to as qualified sets; in turn, the set of all such qualified sets is called the access structure of the system. Less formally it is a description of who needs to cooperate with whom in order to access the resource. In its original use in cryptography, the resource was a secret shared among the participants.  Only subgroups of participants contained in the access structure are able to join their shares to recompute the secret. More generally, the resource can also be a task that a group of people can complete together, such as creating a digital signature, or decrypting an encrypted message.

It is reasonable to assume that access structures are monotone in the sense that, if a subset S is in the access structure, all sets that contain S as a subset should also form part of the access structure.

See also

 Access control
 Secret sharing
 Threshold cryptosystem

References 

Access control
Howard Kapnek Schachman. Howard Kapnek Schachman  (December 5, 1918 – August 5, 2016) was a graduate school professor in the Department of Molecular & Cell Biology at the University of California, Berkeley.

Early life
Schachman was born in Philadelphia in 1918. In high school, he was interested in sociopolitical issues, inspired by his mother. He initially pursued liberal arts in college while studying to become a rabbi, before switching to chemical engineering in a university. He transferred from the University of Pennsylvania to the Massachusetts Institute of Technology, where he graduated in 1939 with a chemical engineering degree.

Graduate studies
He received a Ph.D. from Princeton University in 1948 and joined the faculty of UC Berkeley. He signed but protested the loyalty oath required by the Regents of the University of California during McCarthyism. He was elected to the American Academy of Arts and Sciences (1966) and the United States National Academy of Sciences (1968).

Among many other honors, he received the AAAS Scientific Freedom and Responsibility Award in 2000.

The "Howard K. Schachman Public Service Award" of the ASBMB is named after him.

Teaching career
Each spring, he taught the MCB 293C course on Ethical Conduct of Research required for NIH-funded students. He died at the age of 97 on August 5, 2016.

Personal life
While at Princeton he married Ethel Lazarus.

References

External links
 Home page at the Department of Molecular & Cell Biology, University of California, Berkeley
 death announcement

Princeton University alumni
1918 births
2016 deaths
American biochemists
Jewish American scientists
Members of the United States National Academy of Sciences
University of California, Berkeley faculty
21st-century American Jews
University of Pennsylvania alumni
Massachusetts Institute of Technology alumni
MAT/5 mine. The MAT/5 is an Italian circular, plastic-cased minimum metal blast resistant anti-tank blast mine. It uses a pneumatic fuze which is resistant to shock and blast, and is also claimed to be resistant to mine flails and mine rollers. The mine's plastic case is waterproof, and it can be laid in shallow water. Additionally the mine will function upside down. The mine can be fitted with anti-handling devices. The mine is no longer in production.

Specifications
 Diameter: 290 mm
 Height: 108 mm
 Weight: 7 kg
 Explosive content: 5 kg of Composition B
 Operating pressure: 180 to 310 kg

References
 Jane's Mines and Mine Clearance 2005-2006
 

Anti-tank mines of Italy
SYDI. SYDI (Script Your Documentation Instantly) is an open source project aimed at assisting system administrators in documenting their networks. Hosted on SourceForge, the project provides scripts that target computers running the Windows and Linux operating systems. The Windows scripts are written in VBScript, while the Linux script is written in Python.

Each script serves two basic functions: collecting and reporting. After targeting a system, the script collects information from the target and outputs it to either an XML file or a Microsoft Word document.

SYDI is licensed under the BSD License.

SYDI components 
As of version 2.0, SYDI consists of four separate script packages, each of which targets specific operating systems or applications.

SYDI-Server 
SYDI-Server is the most developed script within the SYDI project. It is used to document Windows servers or clients. It collects information with Windows Management Instrumentation (WMI) and by reading the Windows registry. SYDI-Server finds basic hardware settings, installed software, domain membership, network settings etc.

SYDI-Exchange 
SYDI-Exchange is used to document Microsoft Exchange Server organizations. Information is gathered through LDAP queries to the Active Directory where the Exchange information is stored.

SYDI-SQL 
SYDI-SQL is used to document Microsoft SQL (MS SQL) Servers. Information is gathered by using SQL queries against the target server.

SYDI-Linux 
SYDI-Linux is the least developed package within the SYDI project. Information is gathered by reading various files on a Linux system. SYDI-Linux focuses on documenting the Gentoo Linux distribution. Unlike the other SYDI packages, this is not able to write Microsoft Word documents, however the XML file created can be converted into an OpenOffice document.

SYDI-SMS 
SYDI-SMS is an offshoot of the SYDI project. It was created by a Microsoft MVP to document his System Management Server 2003 unlike the other Microsoft-based SYDI packages, this script only create a Word document.

SYDI-SCCM 
SYDI-SCCM is an offshoot of the SYDI project. It was created by a Microsoft MVP to document his System Center Configuration Manager 2007 unlike the other Microsoft-based SYDI packages, this script only create a Word document. This version will document most of CM12 too.

SYDI-CM12 
SYDI-SCCM is an offshoot of the SYDI project. It was created by a Microsoft MVP to document his System Center Configuration Manager 2012 unlike the other Microsoft-based SYDI packages, this script will only create a Word document. This version will document most of CM12 too.

External links
Official SYDI Website
Creators blog with news about SYDI
SYDI-SMS, SYDI SCCM, and SYDI CM12 scripts

Free documentation generators
Windows network-related software
MAT/6 mine. The MAT/6 is an Italian circular synthetic resin-cased minimum metal blast resistant anti-tank blast mine. It uses a pneumatic fuze which is resistant to shock and blast, and is also claimed to be resistant to mine flails and mine rollers. The mine's plastic case is waterproof, and it can be laid in shallow water. Anti-handling devices may be fitted to the mine.

The mine is no longer in production.

Specifications
 Diameter: 270 mm
 Height: 142 mm
 Weight: 7.1 kg
 Explosive content: 6.3 kg
 Operating force: 180 to 310 kg
 Can be placed Underwater

References
 Janes Mines and Mine Clearance 2005-2006
 

Anti-tank mines of Italy
Best Manufacturing Company. The Best Manufacturing Company (sometimes known as the Daniel Best Company) of San Leandro, California was a manufacturer of farm machinery, known for its steam tractors.

History

The company was formed in 1871 by Daniel Best. The company's initial product was a portable grain cleaner, soon followed by a combine harvester. In 1890, the company purchased the rights to manufacture the Remington steam engine, and produced a range of steam-driven farm machinery, including steam tractors and combine harvesters. In 1891, the company built a gasoline powered locomotive for San Jose and Alum Rock Railroad. This was the first internal combustion locomotive built in the western United States, though it was only a limited success and was returned to Best in 1892.

Around 1900 the company built a number of three wheeled road locomotives. 

The company was acquired by the Holt Manufacturing Company in 1908 after a legal battle. C. L. Best, the son of the founder then formed his own rival company, the C. L. Best Gas Traction Company which built gasoline-powered tractors. This new company acquired the rights to manufacture the Lombard Steam Log Hauler, an early tracked crawler, and began producing "tracklayer" tractors.

Following fierce competition from the Fordson company, C.L. Best merged with the Holt Manufacturing Company in 1925 to form the Caterpillar Tractor Company.

References

External links
 "Daniel Best Builds His First Steam Traction Engine Tractor". Caterpillar.
 Oakland museum's Best tractor
 Page on Best steam tractors
 The Oakland Best operating in 2005

Tractor manufacturers of the United States
Former Caterpillar Inc. subsidiaries
Companies based in San Leandro, California
Defunct manufacturing companies based in the San Francisco Bay Area
Manufacturing companies established in 1871
Manufacturing companies disestablished in 1925
1871 establishments in California
1925 disestablishments in California
History of San Leandro, California
1925 mergers and acquisitions
Colibri. Colibri may refer to

 Colibri (bird), a genus of hummingbird
 Colibri Group, suppliers of cigarette lighters and other items
 Estadio Nido del Colibri, a multi-use stadium in Cuernavaca, Mexico
 COLIBRI, a Lisp machine co-processor
 Rey Mysterio (born 1974), wrestler, by ring name
 Colibri (film), a 1924 German silent film

Transport
 Brügger Colibri, a family of sports aircraft
 Eurocopter Colibri, a helicopter
 HMS Colibri, several vessels of the Royal Navy
 HMS Colibri (1809), a captured French-built naval sloop in the Royal Navy
 IMA Colibri, a one-person electric vehicle
 I.Ae. 31 Colibrí, an Argentine civil trainer aircraft
 Leopoldoff Colibri, a biplane

See also
 Colibri del Sol Bird Reserve, a nature reserve in Colombia
 Kolibri (disambiguation)
 Calibri, a typeface family
Supermarine Scapa. The Supermarine Scapa was a British general reconnaissance flying boat built by Supermarine that was used by the Royal Air Force between 1935 and 1939. It was developed from the Southampton and formed the basis of the Supermarine Stranraer.

Development
After experimenting with a three-engine design of flying boat, the Nanok, Supermarine's chief designer R. J. Mitchell decided that the hydrodynamic design developed in the twin-engined Supermarine Southampton, would be suitable for the next aircraft.

A prototype, designated the Southampton IV, was built. It had a hull that exceeded expectations in tests. An Air Ministry Specification was received in November 1931. The test pilot Joseph "Mutt" Summers took first flew the prototype on 8 July, 1932, by which time the name of the type had been changed to Scapa.

After 15 Scapas were built, production was changed to a more powerful development, the Supermarine Stranraer.

Design

The Scapa's hull was an all-metal structure, while the wing and tail surfaces had metal structure with fabric covering. The two Rolls-Royce Kestrel V12 engines were mounted in nacelles underslung from the upper wing, and there were two fins, each placed at the mid semi-span of the tailplane. Similar to the Southampton, there were three gun positions: one in the nose, and two staggered in the rear fuselage. Each provided with a single .303 British (7.7 mm) caliber Lewis Mk.I machine guns.

Operators

  
 Royal Air Force
 No. 202 Squadron RAF
 No. 204 Squadron RAF
 No. 228 Squadron RAF
 No. 240 Squadron RAF

Specifications (Scapa)

See also

References

Sources

Further reading

  
 

1930s British military reconnaissance aircraft
Flying boats
Scapa
Biplanes
Aircraft first flown in 1932
Twin piston-engined tractor aircraft
Twin-tail aircraft
Ultimate failure. In mechanical engineering, ultimate failure describes the breaking of a material.  In general there are two types of failure: fracture and buckling.  Fracture of a material occurs when either an internal or external crack elongates the width or length of the material.  In ultimate failure this will result in one or more breaks in the material.  Buckling occurs when compressive loads are applied to the material and instead of cracking the material bows.  This is undesirable because most tools that are designed to be straight will be inadequate if curved.  If the buckling continues, it will create tension on the outer side of the bend and compression on the inner side, potentially fracturing the material.

In engineering there are multiple types of failure based upon the application of the material.  In many machine applications any change in the part due to yielding will result in the machine piece needing to be replaced.  Although this deformation or weakening of the material is not the technical definition of ultimate failure, the piece has failed.  In most technical applications, pieces are rarely allowed to reach their ultimate failure or breakage point, instead for safety factors they are removed at the first signs of significant wear.

There are two different types of fracture: brittle and ductile.  Each of these types of failure occur based on the material's ductility.  Brittle failure occurs with little to no plastic deformation before fracture.  An example of this would be stretching a clay pot or rod, when it is stretched it will not neck or elongate, but merely break into two or more pieces.  While applying a tensile stress to a ductile material, instead of immediately breaking the material will instead elongate.  The material will begin by elongating uniformly until it reaches the yield point, then the material will begin to neck.  When necking occurs the material will begin to stretch more in the middle and the radius will decrease.  Once this begins the material has entered a stage called plastic deformation.  Once the material has reached its ultimate tensile strength it will elongate more easily until it reaches ultimate failure and breaks.

See also
 Failure causes
 Material strength
 Fabrication (metal)

References
Manufacturing Processes for Engineering Materials Fifth Edition

Reliability engineering
Maintenance
Sandtoft Airfield. Sandtoft Airfield , also known as Sandtoft Aerodrome, is in Belton, North Lincolnshire, England on the south side of the M180 motorway, approximately  northeast of Doncaster, and  southwest of Scunthorpe. It is managed and operated by E-Plane Ltd.

History

Sandtoft opened in February 1944 as a satellite for No 11 Base, RAF Lindholme in 1 Gp, Bomber Command. 1667 HCU and its Halifax bombers moved in from RAF Faldingworth on 20 February and was the only unit based at Sandtoft. 1667 HCU was also flying Lancasters I III from Sandtoft during 1945, Lancasters with airframe numbers JB306, HK734, HK740 and ME682 being some of them.

Placed on Care and Maintenance after the war, RAF Sandtoft was inactive when allocated to the USAF on 1 April 1953. The station was never occupied by American forces and returned to UK control on 8 September 1955 for disposal. The Sandtoft Flying Club uses part of the old peritrack as a runway.

The airfield
Sandtoft Aerodrome has a CAA Ordinary Licence (Number P873) that allows flights for the public transport of passengers or for flying instruction as authorised by the licensee ( E-Plane Ltd). The aerodrome is not licensed on Weekdays.

Flying instruction at Sandtoft is provided by Yorkshire Aero Club who have a satellite office there to gain their PPL.

Notes

Airports in England
Airports in Lincolnshire
Epworth, Lincolnshire
Isle of Axholme
Digital Reality. Digital Reality Software Kft. (formerly Amnesty Design) was a Hungarian video game developer based in Budapest, Hungary. It was founded in 1991 as Amnesty Design, and started to work on their upcoming title, Reunion, which would be released in 1994 by Grandslam Video, for Amiga and MS-DOS. In 1997, leading up to the release of Imperium Galactica, the company changed its name to Digital Reality. In the following decade, games like Haegemonia: Legions of Iron, Platoon, SkyDrift and Desert Rats vs. Afrika Korps were produced, all to positive reception.

In 2006, Digital Reality opened a subsidiary studio, Whiz Software, in cooperation with CDV Software, and in 2011, they spun off a digital distribution subsidiary, Digital Reality Publishing. Digital Reality silently shut down in 2013. In February 2016, Austrian publisher Nordic Games acquired a range of intellectual properties formerly under the Digital Reality banner, including Black Knight Sword, Imperium Galactica and Sine Mora.

Games developed

References 

Defunct video game companies of Hungary
Video game companies established in 1991
Video game companies disestablished in 2013
Video game development companies
1991 establishments in Hungary
Peter Štefan. Peter Štefan (27 March 1941 in Bratislava, Slovak Republic – 18 June 1978 in Tryfan, Wales) was a Slovak mathematician who was known for his works on dynamical systems and mathematical entropy.

He attended school in Bratislava, and then Charles University in Prague. In 1968, he was involved in politics in Czechoslovakia, supporting the political movement that sought to humanize Communist rule during the Prague Spring. As he was visiting the University of Warwick, though, the Soviet Union and several Warsaw Pact allies invaded the country, installing a Soviet-controlled regime. Štefan feared that he would be in danger if he returned, and he decided to stay in Britain. He remained in Warwick, where he studied for a Ph.D. which was awarded in 1973. His thesis was on Accessibility and singular foliations, a topic which is important in control theory and in the mathematical theory of entropy.

He died while climbing Tryfan on 18 June 1978.

References

External links

Article on Peter Štefan in Matematický ústav SAV

1941 births
1978 deaths
Charles University alumni
Czechoslovak expatriates in the United Kingdom
Czechoslovak mathematicians
Mountaineering deaths
Scientists from Bratislava
Sport deaths in Wales
Cablesoft. Cablesoft was an early attempt to define an interactive television standard. The partners in the new company were Microsoft, Tele-Communications and Time Warner. In fact, much of the effort appeared to be on Microsoft's part, and the two cable companies were essentially launch partners.  

The Cablesoft effort was first announced in May 1994 and at the time consisted primarily of the Microsoft Media Server (codenamed Tiger during development) and a custom version of the Windows NT operating system known as NTAS, which was essentially a series of fine-tuning efforts to drive ATM switches. The basic model appeared to be to use a PC-like set-top box that would communicate with PC's running NTAS at the cable company's head ends, using Tiger to cue up and deliver content.
Cablesoft was succeeded by MSN TV in 1997.

Note
An apparently unrelated company, CableSoft, also delivered on-demand content starting around 1995. The company was headquartered in Burlington, Massachusetts.

References
Turning packaged goods into recurring revenues

Uncompleted Microsoft initiatives
JY15. The JY15 is an American one-design centerboard dinghy designed by Rod Johnstone in 1989.

Production
The boat was built by JY Sailboats and then by Hunter Marine in the United States. The design was acquired by Nickels Boats Works and built from 2011. Nickels merged with WindRider LLC of Minneapolis, Minnesota in 2015 and production continued, but had ended by 2020.

Design
The JY15 is a recreational, planing hull, sailing dinghy, built predominantly of Advanced Composite Process (ACP) by JY Sailboats and Hunter and later from fiberglass by Nickels and WindRider. It has a fractional sloop, a raked stem, a vertical transom, a transom-hung rudder controlled by a  tiller with an extension and a folding centerboard. It displaces .

The boat has a draft of  with the centreboard extended and  with it retracted, allowing beaching or ground transportation on a trailer.

The stays have lever adjusters for rapid set-up and the mast disassembles for ease of ground transport. The mainsheet is a 2:1 and is led off to the centerboard trunk. The rudder swings up for launching and recovering in shallow water. The design is optimized for crew hiking out, with hiking straps and rounded deck and hull for comfort.

The Hunter-production JY-15 was made out of ACP (Advanced Composite Process). ACP is a laminate consisting of a foam core, an inner fiberglass skin, and a 1/8" outer plastic skin. When the design was acquired by Nickels it was rendered in fiberglass.

Operational history
The JY15 is sailed in over 80 fleets in the US.

See also
List of sailing boat types

Similar sailboats
Laser 2

References

External links
Official website archive on Archive.org
Official Hunter Marine brochure

Dinghies
1980s sailboat type designs
Sailboat type designs by Rod Johnstone
Sailboat types built by Hunter Marine
Sailboat types built by Nickels Boat Works
Sailboat types built by WindRider LLC
Radmind. Radmind is a suite of Unix command-line tools and an application server designed to remotely administer the file systems of multiple client machines.

For Mac OS X, there is a graphical user interface called Radmind Assistant, as well as a GUI for the Radmind server called Radmind Server Manager.

Radmind was the 2003 Apple Design Awards runner-up for Best Mac OS X Server Solution.

Radmind is developed by the Research Systems Unix Group at the University of Michigan.

How Radmind Works 
Radmind operates as a tripwire, detecting changes in a client's filesystem (and, in the case of Microsoft Windows, the registry) and reversing the changes. Radmind stores filesystem specifications in text files called transcripts, signified with a .T extension.  Transcripts are referenced from command files, signified with a .K extension, which specify which transcripts (and with what precedence) should be applied to a client machine's filesystem.

Suite of tools 
The radmind suite of tools comprises

 ktcheck, which updates the locally stored command files and transcripts to match those on the server.
 fsdiff, which checks the client filesystem against the transcripts on the local system without using network bandwidth.
 lapply, which updates the client filesystem to match the transcripts, downloading files as needed.
 lcreate, which uploads new transcripts to the server.
 lcksum, which verifies uploaded transcripts.
 lfdiff, which compares local files with copies on Radmind server.
 lmerge, which combines transcripts on the server.
 ra.sh , which automates the update process using ktcheck, fsdiff, and lapply.
 twhich, which returns which transcript(s) a file is referenced in.
 applefile, which allows Radmind to work with AppleSingle files.

References

External links
Radmind wiki
Radmind Manual for Mac OS X
Radmind Deployment & Implementation Documentation

Remote administration software
File managers
Software using the BSD license