omniomni/omni-engineering huggingface dataset:
Fan clutch. A fan clutch is a thermostatic engine cooling fan that can freewheel at low temperatures when cooling is not needed, allowing the engine to warm up faster, relieving unnecessary load on the engine. As temperatures increase, the clutch engages so that the fan is driven by engine power and moves air to cool the engine.

Function
When the engine is cool or even at normal operating temperature, the fan clutch partially disengages the engine's mechanically driven radiator cooling fan, generally located at the front of the water pump and driven by a belt and pulley connected to the engine's crankshaft.  This saves power, since the engine does not have to fully drive the fan.

However, if engine temperature rises above the clutch's engagement temperature setting, the fan becomes fully engaged, thus drawing a higher volume of ambient air through the vehicle's radiator, which in turn serves to maintain or lower the engine coolant temperature to an acceptable level.

Mechanical fans are most common in trucks and SUVs, and some RWD cars. This is easier to accomplish because the engine is mounted longitudinally, with the belt accessory components mounted facing the radiator. The fan is mounted on the crankshaft pulley or one of the accessory pulleys (e.g. the water pump pulley) and will spin in between the radiator and the engine, drawing air back through the radiator and blowing it over the engine.  Even though the air has been heated by passing through the radiator, it is still much less hot than the engine surface, so the airflow over the engine helps with cooling.

In contrast, in a front-wheel drive vehicle, the engine is usually mounted laterally, with the crankshaft and typically all the major accessory shafts parallel to the front axle, so as to directly drive the transaxle; a fan mechanically mounted on an accessory pulley would blow sideways and would not face the radiator.  This is why electric engine-cooling fans are used virtually universally in front-wheel drive vehicles.  The conversion of mechanical energy to electricity and back to mechanical rotary power with a fan motor is less efficient than a direct mechanical connection, but this is more than compensated by greater control of an electric fan through electronic thermostatic controls which can turn the fan completely off when the engine temperature is below the setpoint.

Types
Most fan clutches are viscous or "fluid" couplings, combined with a bi-metallic sensory system similar to that in a thermostat.  Some clutches are electronically controlled (instead of bi-metallic strip).  These provide the potential to control the level of engagement depending on any number of inputs.  Common controlling factors might include engine oil temperature, transmission oil temperature, coolant temperature, AC system pressures and ambient air temperature.

Notes

References 

Engine cooling systems
Clutches
Python Software Foundation. The Python Software Foundation (PSF) is an American nonprofit organization devoted to the Python programming language, launched on March 6, 2001. The mission of the foundation is to foster development of the Python community and is responsible for various processes within the Python community, including developing the core Python distribution, managing intellectual rights, developer conferences including the Python Conference (PyCon), and raising funds.

In 2005, the Python Software Foundation received the Computerworld Horizon Award for "cutting-edge" technology.

Overview 
The PSF focuses on empowering and supporting people within the Python community with grant programs that support sprints, conferences, meetups, user groups, and Python development.  The PSF runs Python Conference (PyCon) US, the leading Python community conference.  The PSF is the primary point of contact for organizations that wish to work with Python, to support Python, or sponsor Python development. The PSF provides a structure by which work, donations, and sponsorships are coordinated worldwide. The PSF also possesses and protects intellectual property associated with Python and the Python community, such as the word "Python," the two-snakes logo, and the terms "PyLadies" and "PyCon."

Membership 
There are five tiers of membership within the PSF. These tiers include:
 Basic members – Basic members are individuals or entities who are part of the Python language community and who have decided to declare their support for Python and agree to the community Code of Conduct.
 Supporting members – Supporting members make an annual donation to the PSF to sustain the foundation and support the Python community. Supporting members are eligible to vote.
 Managing members – Managing members are people who commit to working at least five hours per month to support the Python ecosystem, by organizing Python events, managing or contributing to PSF projects, running infrastructure, participating in one of the PSF's working groups, etc. Managing members are eligible to vote.
 Contributing members – Contributing members are people who dedicate at least five hours per month working on projects that advance the mission of the PSF, where the work relates to the creation or maintenance of open source software available to the public at no charge. Contributing members are eligible to vote.
  Fellows – Fellows are members who have been nominated by their extraordinary efforts and impact upon Python, the community, and the broader Python ecosystem. Fellows are nominated from the broader community and elevated by a vote of the members. Fellow members are eligible to vote.

Code of Conduct 
Since late 2012, the Python Software Foundation started recommending that all Python conferences create and apply a code of conduct. This is mandatory to any event to be granted funds by the Python Software Foundation.

See also 

 PyLadies
 PyCon

References

Further reading

External links 
Python Software Foundation

501(c)(3) organizations
Free software project foundations in the United States
Python (programming language)
Organizations established in 2001
Interaction energy. In physics, interaction energy is the contribution to the total energy that is caused by an interaction between the objects being considered.

The interaction energy usually depends on the relative position of the objects. For example,  is the electrostatic interaction energy between two objects with charges , .

Interaction energy
A straightforward approach for evaluating the interaction energy is to calculate the difference between the objects' combined energy and all of their isolated energies. In the case of two objects, A and B, the interaction energy can be written as:

where  and  are the energies of the isolated objects (monomers), and  the energy of their interacting assembly (dimer).

For larger system, consisting of N objects, this procedure can be generalized to provide a total many-body interaction energy:

By calculating the energies for monomers, dimers, trimers, etc., in an N-object system, a complete set of two-, three-, and up to N-body interaction energies can be derived.

The supermolecular approach has an important disadvantage in that the final interaction energy is usually much smaller than the total energies from which it is calculated, and therefore contains a much larger relative uncertainty. In the case where energies are derived from quantum chemical calculations using finite atom-centered basis functions, basis set superposition errors can also contribute some degree of artificial stabilization.

See also
 Energy
 Force
 Interaction
 Ideal solution
 Perturbation theory (quantum mechanics)
 Potential

References 

Statistical mechanics
Energy (physics)
Chemical Markup Language. Chemical Markup Language (ChemML or CML) is an approach to managing molecular information using tools such as XML and Java. It was the first domain specific implementation based strictly on XML, first based on a DTD and later on an XML Schema, the most robust and widely used system for precise information management in many areas. It has been developed over more than a decade by Murray-Rust, Rzepa and others and has been tested in many areas and on a variety of machines.

Chemical information is traditionally stored in many different file types which inhibit reuse of the documents. CML uses XML's portability to help CML developers and chemists design interoperable documents. There are a number of tools that can generate, process and view CML documents. Publishers can distribute chemistry within XML documents by using CML, e.g. in RSS documents.

CML is capable of supporting a wide range of chemical concepts including:
 molecules
 reactions
 spectra and analytical data
 computational chemistry
 chemical crystallography and materials

Details of CML and points currently under discussion are now posted on the CML Blog.

Versioning 
Versions of the schema are available at SourceForge. As of April 2012, the latest frozen schema is CML v2.4. Some constructs in CML v1 are now deprecated.

Tools 
JUMBO began life as the Java Universal Molecular Browser for Objects but is now a Java library that supports validation, reading and writing of CML as well as conversion of several legacy formats to CML and, for example, a reaction in CML to an animated SVG representation of the reaction. JUMBO has evolved into an extensive Java library, CMLDOM, supporting all elements in the schema. Although JUMBO used to be a browser, the preferred approach is to use the Open Source tools Jmol and JChemPaint, some of which use alternative CML libraries. See Blue Obelisk.

Software support
Software importing and exporting a valid CML format
Bioclipse
CDK
JOELib
OpenBabel
Avogadro
XDrawChem
OpenChrom

See also
List of document markup languages
Comparison of document markup languages
JCAMP-DX (another well-known standard, especially for spectroscopic data)
Blue Obelisk community for Open Source chemical software
MathML

References

Further reading

External links 
Chemical Markup Language (CML) This includes the CML Schema, links to tools, documentation, and source code
Discussion list
CML Blog
The original (old) site

Markup languages
Industry-specific XML-based standards
Chemical file formats
Cheminformatics
Computational chemistry
Computer-related introductions in 1999
Uppaal Model Checker. UPPAAL is an integrated tool environment for modeling, validation and verification of real-time systems modeled as networks of timed automata, extended with data types (bounded integers, arrays etc.).

It has been used in at least 17 case studies since its release in 1995, including on Lego Mindstorms, for the Philips audio protocol, and in gearbox controllers for Mecel.

The tool has been developed in collaboration between the Design and Analysis of Real-Time Systems group at Uppsala University, Sweden and Basic Research in Computer Science at Aalborg University, Denmark.

There are the following extensions available:
Cora for Cost Optimal Reachability Analysis.
Tron for Testing Real-time systems ON-line (black-box conformance testing).
Cover for COVERerage-optimal off-line test generation.
Tiga for TImed GAmes based controller synthesis.
Port for component based timed systems, exploiting Partial Order Reduction Techniques.
Pro for PRObabilistic reachability analysis. (Discontinued)
SMC for Statistical Model Checking.

References

External links
UPPAAL academic website
UPPAAL commercial website
Design and Analysis of Real-Time Systems group 
DEIS unit, Dept. Computer Science at AAU

Model checkers
Alouette 2. Alouette 2 was a Canadian research satellite launched at 04:48 UTC on November 29, 1965, by a Thor Agena rocket with Explorer 31 from the Western test range at Vandenberg AFB in California. It was (like its predecessor Alouette 1, and Explorer 31) designed to explore the ionosphere.

History
The name "Alouette" came from the French for "skylark" and from the title of a popular French-Canadian folk song.  Alouette 2 was also known as ISIS-X since it was the first in a series of ISIS satellites:  International Satellites for Ionospheric Studies.  The next one was called ISIS-I.

The Alouette 2 was built up from the identical backup satellite to Alouette 1. It had many more experiments and more sophisticated support systems than the earlier satellite.  It lasted for 10 years, being terminated on August 1, 1975.

RCA Victor of Montreal, Quebec, was the prime contractor; Havilland Aircraft of Toronto, Ontario, served as associate contractor.

Post mission
After the Alouette 2 was launched, the upper stage of the rocket used to launch the satellite became a derelict object that would continue to orbit Earth for many years.  , the upper stage remains in orbit.

The satellite itself became a derelict after August 1975.  It too remains in earth orbit .

References

External links

1965-098A at NSSDC
CBC Archives: Launching the Alouette 2 satellite

Satellites of Canada
Derelict satellites orbiting Earth
Spacecraft launched in 1965
Geospace monitoring satellites
Be File System. The Be File System (BFS) is the native file system for the BeOS. In the Linux kernel, it is referred to as "BeFS" to avoid confusion with Boot File System.

BFS was developed by Dominic Giampaolo and Cyril Meurillon over a ten-month period, starting in September 1996, to provide BeOS with a modern 64-bit-capable journaling file system. It is case-sensitive and capable of being used on floppy disks, hard disks and read-only media such as CD-ROMs. However, its use on small removable media is not advised, as the file-system headers consume from 600 KB to 2 MB, rendering floppy disks virtually useless.

Like its predecessor, OFS (Old Be File System, written by Benoit Schillings - formerly BFS), it includes support for extended file attributes (metadata), with indexing and querying characteristics to provide functionality similar to that of a relational database.

Whilst intended as a 64-bit-capable file system, the size of some on-disk structures mean that the practical size limit is approximately 2 exabytes. Similarly the extent-based file allocation reduces the maximum practical file size to approximately 260 gigabytes at best and as little as a few blocks in a pathological worst case, depending on the degree of fragmentation.

Its design process, application programming interface, and internal workings are, for the most part, documented in the book Practical File System Design with the Be File System.

Implementations
In addition to the original 1996 BFS used in BeOS, there are several implementations for Linux. In early 1999, Makoto Kato developed a Be File System driver for Linux; however, the driver never reached a completely stable state, so in 2001 Will Dyson developed his own version of the Linux BFS driver.

In 2002, Axel Dörfler and a few other developers created and released a reimplemented BFS called OpenBFS for Haiku (OpenBeOS back then). In January 2004, Robert Szeleney announced that he had developed a fork of this OpenBFS file system for use in his SkyOS operating system. The regular OpenBFS implementation was also ported to Syllable, with which it has been included since version 0.6.5.

See also
 Comparison of file systems
 AtheOS File System

References

External links
 The BeOS file system: an OS geek retrospective, by Andrew Hudson, 2010-06-03, Ars Technica

Disk file systems
BeOS
Haiku (operating system)
Giovanni Ciccotti. Giovanni Ciccotti (born 19 December 1943, in Rome Italy) is an Italian physicist.

Ciccotti held the position of Professor of the Structure of Matter at the University of Rome La Sapienza until 2013. He is the author of more than a hundred articles on molecular dynamics and statistical mechanics. He worked with J.P. Ryckaert on new methods for molecular dynamics on constrained systems. See also SHAKE algorithm.

He has edited several books on molecular dynamics and statistical mechanics developments, including:

  "Molecular Dynamics Simulation of Statistical Mechanical Systems", E. Fermi 1985 Summer School. G. Ciccotti and W. G. Hoover Eds. North Holland, Amsterdam, 1986.
 "Simulation of Liquids and Solids. Molecular Dynamics and MonteCarlo Methods in Statistical Mechanics. A reprint Book". G. Ciccotti, D. Frenkel and I. R. Mc Donald, Eds. North Holland, Amsterdam, 1987.
 "MonteCarlo and Molecular Dynamics of Condensed Matter Systems", Euroconference 1995, K. Binder and G. Ciccotti, Eds., SIF, Bologna, 1996.
 "Simulation of Classical and Quantum Dynamics in Condensed Phase", Euroconference 1997, B. J. Berne, G. Ciccotti and D. F. Coker, Eds. World Scientific, Singapore, 1998.

References

External links
 

1943 births
Living people
Academic staff of the Sapienza University of Rome
20th-century Italian physicists
Neoclassic (automobile). A neoclassic, in automobile circles, is a relatively modern car that is made somewhat in the image of the classic cars of the 1920s and 1930s (as defined by, for example, the Classic Car Club of America) without being necessarily intended as a full replica. They are vehicles that hold the design prior to Ponton design, so they still keep the wheel arches separate from the bodywork.

The term originated with the Excalibur automobile in the 1960s in the United States, and has been applied to cars from a number of makes since then, including Panther, Zimmer, Clénet, Mitsuoka, Desande, Spartan and others. Currently there are more than 30 brands that produce Neoclassic cars.

See also
 Retro-style automobile

References

Retro-style automobiles
Wizards of OS. Wizards of OS (Wizards of Operating Systems, or "WOS") was a semi-annual Berlin-based conference that was held four times between 1999 and 2006. Its topics were the cultural and political potentials of free software, software technology, digital networks and media, and more generally information freedom and open cooperation in the creation and proliferation of knowledge. The conference was interdisciplinary, and included among its attendees scientists, engineers, social researchers, scholars from the humanities, artists and activists.

The name was a word play on The Wizard of Oz. The acronym "OS" stands for operating system (not open source).

Individual conferences
The first Wizards of OS conference took place in 1999.

The third conference took place in 2004, with the subtitle "The Future of the Digital Commons". It featured, among others, the launch of the German translation of the Creative Commons licenses.

Wizards of OS 4 took place from September 14 to September 16, 2006, with the subtitle "Information Freedom Rules". Some of the topics were the future of Creative Commons, open music and the compensation of artists and European copyright legislation. Larry Sanger announced an initial proposal of his project Citizendium.

References

External links

 Wizards of OS homepage
 Archive of video and audio recordings from the sessions

Computing and society
Free-software conferences
Recurring events established in 1999
Recurring events disestablished in 2006
ACSL. ACSL may refer to:

 American Computer Science League, a computer science competition primarily among US high school students
 Advanced Continuous Simulation Language, a computer language
 ANSI/ISO C Specification Language, a formal specification language for C programs
 Association of School and College Leaders, a British professional association
 Human genes encoding Acyl-CoA synthetase long-chain enzymes:
 ACSL1
 ACSL3
 ACSL4
 ACSL5
 ACSL6
 SLC27A2
 The Anti-Capitalist Software License
Zohar Manna. Zohar Manna (1939 – 30 August 2018) was an Israeli-American computer scientist who was a professor of computer science at Stanford University.

Biography 
He was born in Haifa, Mandatory Palestine in 1939. He earned his Bachelor of Science (BS) and Master of Science (MS) degrees from the Technion – Israel Institute of Technology.

He attended Carnegie Mellon University and earned his Doctor of Philosophy (PhD) in computer science in 1968.

Manna returned to Israel in 1972 as a professor of applied mathematics at the Weizmann Institute of Science. He became a full professor at Stanford in 1978. He remained affiliated with the Weizmann Institute of Science until 1995. He continued to work as a Stanford professor until retirement in 2010.

Books 
He authored nine books. The Mathematical Theory of Computation (McGraw Hill, 1974; reprinted Dover, 2003) is one of the first texts to provide extensive coverage of the mathematical concepts behind computer programming.

With Amir Pnueli, he co-authored an unfinished trilogy of textbooks on temporal logic and verification of reactive systems: The Temporal Logic of Reactive and Concurrent Systems: Specification (Springer-Verlag, 1991), The Temporal Logic of Reactive and Concurrent Systems: Safety (Springer-Verlag, 1995) and The Temporal Logic of Reactive and Concurrent Systems: Progress (unpublished; first three chapters posted at http://theory.stanford.edu/~zm/tvors3.html).

With Aaron R. Bradley he co-authored a textbook, The Calculus of Computation, that serves as an introduction to both first-order logic and formal verification.

Awards 
In 1994, he was inducted as a Fellow of the Association for Computing Machinery. In 2016, he shared the Herbrand Award with Richard Waldinger for his ″pioneering research and pedagogical contributions (with Richard Waldinger) to automated reasoning, program synthesis, planning, and formal methods″. He received the Bauer Prize from the Technical University of Munich, and an honorary doctorate from the École Normale Supérieure de Cachan.

Advising 
He supervised 30 doctoral students, including Nachum Dershowitz, Adi Shamir, Thomas Henzinger, Pierre Wolper, and Martín Abadi.

See also
 Temporal logic
 Reactive systems
 Concurrency (computer science)

References

External links

1939 births
2018 deaths
Educators from Haifa
Stanford University School of Engineering faculty
1994 fellows of the Association for Computing Machinery
Carnegie Mellon University alumni