omniomni/omni-engineering huggingface dataset:
Zero force member. In the field of engineering mechanics, a zero force member is a member (a single truss segment) in a truss which, given a specific load, is at rest: neither in tension, nor in compression.

Description

In a truss, a zero-force member is often found at pins (any connections within the truss) where no external load is applied, and three or fewer truss members meet. Basic zero-force members can be identified by analyzing the forces acting on an individual pin in a physical system.

If the pin has an external force or moment applied to it, then all of the members attached to that pin are not zero-force members unless the external force acts in a manner that fulfills one of the rules:
 If two non-collinear members meet in an unloaded joint, both are zero-force members.
 If three members meet in an unloaded joint, of which two are collinear, then the third member is a zero-force member.

Restated for clarity, when there are no external loads at a pin joint, the two rules that determine zero-force members are: 
 If a joint in a truss has only two non-collinear members and no external load or support reaction is applied at that joint, then both members are zero-force members.
 If three members form a joint and two of these members are collinear while the third member is not, and no external load or support reaction is applied at the joint, the third non-collinear member is a zero-force member.

Reasons to include zero force members in a truss system
It is a common practice to eliminate zero force members from a truss to simplify analysis. Although an absolute minimalist design might eliminate all zero force elements from a truss, there are still sound reasons to retain some of these components in actual built systems:
These members can contribute to the stability of the structure by preventing buckling of long, slender members under compressive forces
These members can increase rigidity when variations are introduced in the normal external loading configuration, including dynamic and variable forces.

See also
 Structural engineering
 Neutral plane

External links
 Truss Overview
 Another Truss Overview

References

Structural analysis
Statics
UKUUG. UKUUG is the UK's Unix and Open Systems User Group a non-profit organization and technical forum for the advocacy of open systems, particularly Unix and Unix-like operating systems, the promotion of Free and Open Source Software (FOSS), and the advancement of open programming standards and networking protocols.

In 2010 the name has been changed to FLOSS UK, along with a change of web domain.

See also
EFF
FSF
Online Rights Canada

External links

References

Computer science in the United Kingdom
Information technology organisations based in the United Kingdom
User groups
Turbosteamer. A turbosteamer is a BMW combined cycle engine using a waste heat recovery unit. Waste heat energy from the internal combustion engine is used to generate steam for a steam engine which creates supplemental power for the vehicle. The turbosteamer device is affixed to the exhaust and cooling system. It salvages the heat wasted in the exhaust and radiator (as much as 80% of heat energy) and uses a steam piston or turbine to relay that power to the crankshaft. The steam circuit produces  and  of torque at peak (for a 1.8 straight-4 engine), yielding an estimated 15% gain in fuel efficiency. Unlike gasoline-electric hybrids, these gains increase at higher, steadier speeds.

Timescale
BMW has been the pioneer of this concept as early as 2000 under the direction of Dr. Raymond Freymann, and while they were designing this system to fit to most current BMW models, the technology didn't reach production.

See also
 COGAS
 Cogeneration
 Exhaust heat recovery system
 Still engine
 Turbo-compound engine

Publications
 R. Freymann, W. Strobl, A. Obieglo: The Turbosteamer: A System Introducing the Principle of Cogeneration in Automotive Applications. Motortechnische Zeitschrift, MTZ 05/2008 Jahrgang 69, pp.404-412.

References

External links
Gizmag article discussing BMW's turbosteamer
Article on BMW's alternative Combined Cycle Hybrid technology
Looking for the next gram. BMW Group. Retrieved 5 December 2011.

Engine technology
Steam power
Tea (programming language). Tea is a high-level scripting language for the Java environment. It combines features of Scheme, Tcl, and Java.

Features
 Integrated support for all major programming paradigms.
 Functional programming language.
 Functions are first-class objects.
 Scheme-like closures are intrinsic to the language.
 Support for object-oriented programming.
 Modular libraries with autoloading on-demand facilities.
 Large base of core functions and classes.
 String and list processing.
 Regular expressions.
 File and network I/O.
 Database access.
 XML processing.
 100% pure Java.
 The Tea interpreter is implemented in Java.
 Tea runs anywhere with a Java 1.6 JVM or higher.
 Java reflection features allow the use of Java libraries directly from Tea code.
 Intended to be easily extended in Java. For example, Tea supports relational database access through JDBC, regular expressions through GNU Regexp, and an XML parser through a SAX parser (XML4J for example).

Interpreter alternatives 

Tea is a proprietary language. Its interpreter is subject to a non-free license. A project called "destea", which released as Language::Tea in CPAN, provides an alternative by generating Java code based on the Tea code.

TeaClipse is an open-source compiler that uses a JavaCC-generated parser to parse and then compile Tea source to the proprietary Tea bytecode.

References

External links 
 Tea Home Page
 "destea" code converter

Scripting languages
Programming languages
High-level programming languages
Programming languages created in 1997
Anubis (cipher). Anubis is a block cipher designed by Vincent Rijmen and Paulo S. L. M. Barreto as an entrant in the NESSIE project, a former research program initiated by the European Commission in 2000 for the identification of new cryptographic algorithms. Although the cipher has not been included in the final NESSIE portfolio, its design is considered very strong, and no attacks have been found by 2004 after the project had been concluded. The cipher is not patented and has been released by the designers for free public use.

Anubis operates on data blocks of 128 bits, accepting keys of length 32N bits (N = 4, ..., 10). It is designed as a substitution–permutation network, which bears large similarity to Rijndael. Like KHAZAD, designed by the same authors and also submitted to NESSIE, it uses involutions for the various operations. An involution is an operation whose inverse is the same as the forward operation.  In other words, when an involution is run twice, it is the same as performing no operation.  This allows low-cost hardware and compact software implementations to use the same operations for both encryption and decryption.  Both the S-box and the mix columns operations are involutions. Although many involutional components can make a cipher more susceptible to distinguishing attacks exploiting the cycle structure of permutations within the cipher, no attack strategy for the Anubis cipher has been presented.

There are two versions of the Anubis cipher; the original implementation uses a pseudo-random S-box.  Subsequently, the S-box was modified to be more efficient to implement in hardware; the newer version of Anubis is called the "tweaked" version.

The authors claim the algorithm to be secure against a number of attacks, including four-round differential and linear analysis, as well as related-key, interpolation, boomerang, truncated differential, impossible differential, and saturation attacks. Nonetheless, because of the cipher's similarity with Rijndael it was not considered to offer any convincing advantages and thus was not included in the second evaluation phase of the NESSIE project.

Anubis is named after the Egyptian god of entombing and embalming, which the designers interpreted to include encryption. They claim that violators of the cipher will be cursed.

References

External links
 The ANUBIS Block Cipher by Paulo S. L. M. Barreto
 256bit Ciphers - ANUBIS Reference implementation and derived code

Block ciphers
Free ciphers
Instruction list. Instruction list (IL) is one of the 5 languages supported by the initial versions of IEC 61131-3 standard, and subsequently deprecated in the third edition.

It is designed for programmable logic controllers (PLCs). It is a low level language and resembles assembly. All of the languages share IEC61131 Common Elements. The variables and function call are defined by the common elements so different languages can be used in the same program.

Program control (control flow) is achieved by jump instructions and function calls (subroutines with optional parameters).

The file format has now been standardized to XML by PLCopen.

Example

Variations from IEC 61131
Many vendors whilst incorporating the full IEC 61131-3 requirements have additional vendor specific calls/function blocks to suit their hardware such as reading or writing to I/O.
Siemens PLC instruction list language is known as "Statement List" or "STL" in English, and "Anweisungs-Liste" or "AWL" in German, Italian and Spanish. The user of a Simatic development package may choose between German and International mnemonics to represent instructions. For example, "A" for "AND" or "U" for "UND", "I" for "Input" or "E" for "Eingang".

See also
 1-bit architecture

References

External links
 

IEC 61131-3
Programmable logic controllers
Agateware. Agateware is pottery decorated with a combination of contrasting colored clays.

The name agateware is derived from the agate stone, which when sliced shows multicolored layers. This pottery technique allows for both precise and thought out patterns, and free random effects.

Technique
In order to avoid cracking and breaking which come along with mixing a variety of different kinds of clay, potters generally use one white or very light clay as a base. They then add colors in the form of stains or oxides. Colorant is added to the clay when it is in powder form in order to avoid blistering. 1–10% of colorant is generally applied, however it is up to the individual taste of the potter. The drying process is the most crucial part of this technique.

In Japan it is called nerikomi.

Further reading
Cosentino, Peter. The Encyclopedia Of Pottery Techniques. Philadelphia: Running P, 1990. 11–13.

External links
Definition of agateware
Agateware from the Encyclopædia Britannica
 A video example of how an agateware piece is done from the V&A Museum

Types of pottery decoration
USS Alexandria (PF-18). USS Alexandria (PF-18), originally classified PG-126, a Tacoma-class frigate, was the second ship of the United States Navy to hold that name, but it was the first to be named for the city of Alexandria, Virginia.

Construction
The second Alexandria (PF-18) was laid down under a Maritime Commission contract (MC hull 1848) on 23 June 1943, at the American Ship Building Company in Lorain, Ohio; launched on 15 January 1944, sponsored by Mrs. J. Leslie Hall; and towed down the Mississippi River to New Orleans, Louisiana, where she was fitted out and then commissioned on 11 March 1945.

Service history
Alexandria conducted shakedown and anti-submarine warfare (ASW) training out of Guantánamo Bay, Cuba, in late March and early April.  She concluded shakedown on 19 April and put into the Norfolk Navy Yard on the 22nd to begin post-shakedown availability.  Her repairs were finished on 4 May, and three days later, the war in Europe ended.  The latter event obviated the primary mission for which she had been constructed, prosecution of the Battle of the Atlantic against German U-boats.  Thus, when she reported for duty with the Commander, Destroyers, Atlantic Fleet, on 15 May, the patrol frigate received an alternative assignment as a weather ship.  After receiving modifications at the Charleston Navy Yard, she began weather patrol duty off the Newfoundland coast late in June 1945.

That duty, broken only by a visit to Alexandria, Virginia, in late October and early November, lasted until February 1946 when the ship was declared surplus to the needs of the Navy.  She arrived at the Boston Naval Shipyard on 12 February and remained there just under one month.  On 12 March, Alexandria arrived in Norfolk, Virginia, where she was decommissioned on 10 April 1946.  Her name was struck from the Navy list on 21 May 1946.  On 18 April 1947, the former patrol frigate was sold to the Sun Shipbuilding & Drydock Company of Chester, Pennsylvania, for scrapping.

References

External links 
 
hazegray.org: USS Alexandria

Tacoma-class frigates
World War II patrol vessels of the United States
Ships built in Lorain, Ohio
1944 ships
Weather ships
Kallitype. Kallitype is a process for making photographic prints.

Patented in 1889 by W. W. J. Nicol (1855-1929), the Kallitype print is an iron-silver process. A chemical process similar to the Van Dyke brown based on the use of a combination of ferric and silver salts. While Van Dyke brown and argyrotype use ferric ammonium citrate, the light-sensitive element used for the Kallitype is ferric oxalate. The use of ferric oxalate allows for both extended shadow definition (higher DMAX) and contrast control.

Many developing solutions can be used to give a different image color (brown, sepia, blue, maroon and black). Kallitype images generally have a richer tonal range than the cyanotype. These prints were popular in the 19th century, and then their popularity faded away. Sometimes known as "the poor man's platinum print", when the image is toned in platinum or palladium the result is nearly chemically identical to a true Platinotype. It is believed that many Kallitypes were passed off as true Platinotypes and remain in collections as so. Kallitypes have had a reputation over the years as having poor archival qualities and often fading. When properly cleared, Kallitypes are completely archivable and will not fade. Toning with a metal such as gold, platinum, or palladium will give extra image permanence. Ferrous ions embedded in the paper as a result of poor clearing is the cause of the lack of belief in image permanence. This can be easily identified by a yellow stain in the highlights.

Process

Like the Platinotype and Cyanotype, the kallitype is a contact printing process and the printer must have a negative of equal size to print from. Modern kallitypes are generally made from either a large format camera negative, an enlarged internegative from a traditional wet darkroom, or a digital negative. Cotton rag paper is generally recommended for printing kallitypes, although multiple paper types will lead to satisfactory results. Gloves should be worn during coating and when handling sensitizer as  the sensitizer chemicals can be quite toxic.
While the Van Dyke Brown and Argyrotype are both "printing out" processes (with the complete image being formed during exposure), the Kallitype is a "develop out" process that requires the print to be submerged in a developer solution to make the image visible after exposure. Like the Platinotype, the image will appear instantly when the paper is submerged in the developer.

The final tone of the print is controlled both via the developer choice and through the use of toning solutions such as gold and platinum toners.

References

External links
 Making Kallitype Prints at Unblinking Eye
  The Kallitype Process at alternativephotography.com
  Kallitype Development demonstration on Youtube

Photographic processes dating from the 19th century
Audiovisual introductions in 1889
Chassis ground. A chassis ground is a link between different metallic parts of a machine to ensure an electrical connection between them. Examples include electronic instruments and motor vehicles.

Usages
 Electronics  Most electronic systems have their circuits reference-linked to the chassis while the chassis itself is often, but not always, linked to the Earth.
 Motor vehicles  Most motor vehicles use the chassis as the reference for all electrical peripherals which allow the use of only one wire for each accessory.

Confusion
The chassis must not be considered as a link to Earth. Depending on the usage of electrical machines, this may or may not be the case. For example, in all cars metallic parts are linked together but they are not linked to the Earth. This explains why one can experience electrical discharge when leaving a car.

See also
 Floating ground
 Ground (electricity)

References

Electric power
Electrical safety
Electronics
Tungsten film. Tungsten film is photographic film designed to accurately represent colors as perceived by humans under tungsten light; the more usual color films are "daylight films", balanced to produce accurate colours under direct light from the sun or electronic flash. Tungsten film was developed for photographers who use tungsten lights, also known as photofloods, which have a much lower color temperature than daylight, at 3200 kelvins or 3400 kelvins. It also renders colors more accurately than daylight film under ordinary household incandescent lighting.

On daylight-balanced film tungsten lighting produces a spectrally accurate rendition of a scene; but human vision adjusts to the color of the lighting and perceives colors as if under daylight, seeing a spectrally accurate image as having a yellow-orange cast. Tungsten film is balanced in such a way that this lighting is recorded with a subjectively neutral color balance. When shot outdoors, tungsten film produces a strong blue cast, an effect which is often used purposely to create different color contrasts. In the motion picture industry the use of underexposed tungsten-balanced film in an outdoor setting is a common way of producing a "day for night" effect, whereby film shot during the daytime looks as if it had been shot at night.

Tungsten slide films are designed to provide accurate exposure as well as color rendition even when exposed according to exposure meter readings indicating a long exposure; tungsten film can be used to avoid reciprocity failure which often occurs when using long exposures. Common film speeds for tungsten-balanced slide film are ISO 64, 160, and 320.

Examples

 Cinestill 800t

 Kodak 500t

 Ektachrome 64T

References
Hedgecoe, John. The New Manual of Photography. 1st ed. New York: DK Inc, 2003. 128-130.

https://cinestillfilm.com/collections/800tungs

https://www.kodak.com/uploadedfiles/motion/TI2647.pdf

Photographic film types
Fermi Linux. Fermi Linux is the generic name for Linux distributions that are created and used at Fermi National Accelerator Laboratory (Fermilab). These releases have gone through different names: Fermi Linux, Fermi Linux LTS, LTS, Fermi Linux STS, STS, Scientific Linux Fermi, SLF.  For the purposes of this entry they can be used interchangeably to designate a version of Linux specific to Fermilab.

At the current time, the only officially supported Fermi Linux is Scientific Linux Fermi, which is based on Scientific Linux.

History
Fermi Linux started out as an extension of the PC Farms Pilot Project spearheaded by Connie Sieh.  A Fermilab initiative to seek out cost effective computing for the Tevatron.  Continuing to update the SGI and AIX hardware for the computing needs of that experiment was very expensive.

Initial builds of Fermi Linux were merely Red Hat Linux with some things turned off or some extra packages added.  With the release of Scientific Linux, Fermi Linux became a 'site' specific build of Scientific Linux.

Releases

Support policy
Fermi Linux follows the Scientific Linux life cycle regarding support and updates.

There is a vibrant Linux community at Fermilab.  This includes dedicated email lists and regular meetings provided by the Scientific Linux development team.

Fermi Linux LTS
Fermi Linux LTS is in essence Red Hat Enterprise Linux, recompiled.

Workers in Fermilab took the source code from Red Hat Enterprise Linux in srpm form and recompiled them resulting in binaries in rpm form with the only restrictions being the license from the original source code.  They are bundling these binaries into a Linux distribution that is as close to Red Hat Enterprise Linux as they can get.  The goal is to ensure that if a program runs and is certified on Red Hat Enterprise Linux, then it will run on the corresponding Fermi Linux release.

See also

Fermi National Accelerator Laboratory (Fermilab)
Scientific Linux
Linux
Red Hat Linux
Red Hat Enterprise Linux (RHEL), commercial Linux distribution on which Fermi Linux is based
CentOS, another Linux distribution based on Red Hat Enterprise Linux

External links

References

Fermilab
RPM-based Linux distributions
X86-64 Linux distributions
Linux distributions
WSFL. WSFL may refer to:

Web Services Flow Language, an XML language proposed by IBM to describe the composition of Web services
Western Sydney Freight Line, a proposed railway line in Sydney, Australia
WSFL-TV, a television station (channel 27, virtual channel 39) licensed to Miami, Florida, United States
WSFL-FM, a radio station (106.5 FM) licensed to New Bern, North Carolina, United States
Western States Football League
Windows Subsystem for Linux
Women's Spring Football League
Kyushu K11W. The Kyūshū K11W Shiragiku (白菊, "White Chrysanthemum"), made by the Kyūshū Aircraft Company, was a land-based bombing trainer aircraft, which served in the Imperial Japanese Navy Air Service in the later years of World War II. As indicated by its Japanese designation, "training aircraft for on-board work" (機上作業練習機, kijō sagyō renshū-ki?), it was designed to train crews in operating equipment for bombing, navigation, and communication, as well as navigation techniques. A total of 798 K11Ws were manufactured, including a small number of K11W2 ASW and transport aircraft alongside the K11W1 trainer variant. These aircraft were also used in kamikaze missions during the last stages of the Pacific War.

Design and development

The Kyūshū K11W had a rather simple, mid-wing layout. The crew consisted of a pilot and gunner/radio operator sitting in line under the canopy, while the trainee bombardier, trainee navigator, and instructor were located in the lower fuselage beneath the wing.

The K11W served as the basis for the Q3W1 Nankai (南海, "South Sea") anti-submarine patrol aircraft, which did not progress beyond the development phase. It was enlarged but, unlike the K11W, had retracting landing gear.

Variants

 K11W1 : The basic bomber crew trainer, of all-metal construction with fabric-covered control surfaces.
 K11W2 : Anti-submarine warfare and transport version of all-wood construction.
 Q3W1 Nankai : Dedicated Anti-submarine warfare aircraft based on the K11W. 1 built.

Specifications (K11W1)

See also

References
Notes

Bibliography

  (new edition 1987 by Putnam Aeronautical Books, .)
 Mondey, David. The Concise Guide to Axis Aircraft of World War II. London: Chancellor Press, 1996. .

External links

 K11W at www.combinedfleet.com
 K11W at military.sakura.ne.jp  (Japanese)

1940s Japanese military trainer aircraft
Kyūshū aircraft
Mid-wing aircraft
Sodium chloride (data page). This page provides supplementary chemical data on sodium chloride.

Material safety data sheet  

The handling of this chemical may incur notable safety precautions. It is highly recommended that you seek the material safety data sheet (MSDS) for this chemical from a reliable source  such as eChemPortal, and follow its direction.

Structure and properties

Thermodynamic properties

Density data of aqueous solutions 

Note: ρ is density, n is refractive index at 589 nm, and η is viscosity, all at 20 °C; Teq is the equilibrium temperature between two phases: ice/liquid solution for Teq < 0–0.1 °C and NaCl/liquid solution for Teq above 0.1 °C.

Spectral data

References

External links
vapour pressure J Chem Thermod

Chemical data pages
Chemical data pages cleanup