omniomni/omni-engineering huggingface dataset:
Spark-ignition engine. A spark-ignition engine (SI engine) is an internal combustion engine, generally a petrol engine, where the combustion process of the air-fuel mixture is ignited by a spark from a spark plug. This is in contrast to compression-ignition engines, typically diesel engines, where the heat generated from compression together with the injection of fuel is enough to initiate the combustion process, without needing any external spark.

Fuels
Spark-ignition engines are commonly referred to as "gasoline engines" in North America, and "petrol engines" in Britain and the rest of the world. Spark-ignition engines can (and increasingly are) run on fuels other than petrol/gasoline, such as autogas (LPG), methanol, ethanol, bioethanol, compressed natural gas (CNG), hydrogen, and (in drag racing) nitromethane.

Working cycle
The working cycle of both spark-ignition and compression-ignition engines may be either two-stroke or four-stroke.

A four-stroke spark-ignition engine is an Otto cycle engine. It consists of following four strokes: suction or intake stroke, compression stroke, expansion or power stroke, exhaust stroke. Each stroke consists of 180 degree rotation of crankshaft rotation and hence a four-stroke cycle is completed through 720 degree of crank rotation. Thus for one complete cycle there is only one power stroke while the crankshaft turns by two revolutions.

See also
Multifuel engine

References

Spark plugs
Internal combustion piston engines
Tom Cross (computer security). Tom Cross (born 1976), also known as Decius, is an American computer security expert and hacker.

Early life 
Cross was born in 1976 in Toronto, Ontario, Canada, and grew up in Tennessee. His father worked in telecommunications policy and his mother was a Registered Nurse's Assistant. He attended Brentwood High School in Brentwood, Tennessee, before attending Georgia Tech in Atlanta, receiving a bachelor's degree in computer engineering.

Security work 
He co-founded the EFGA (Electronic Frontiers Georgia) in 1995. In 1996, he co-founded Computer Sentry Software, known for their award-winning "CyberAngel" software, a laptop anti-theft program. From 1999 to 2000, he was Chief Engineer at Dataway, a computer security firm in San Francisco. From 2000 to 2001 he worked at iAsiaWorks, as the Director of Global Security Engineering. In 2001, he founded Industrial Memetics, which developed the popular collaborative blogging community MemeStreams.

Cross has been a speaker at several technology conferences, including PhreakNIC; Summercon; "The First International Hackers' Conference in Seoul Korea" (IS2K); "InternetWorld" in Singapore; and APRICOT, the Asia-Pacific Regional Internet Conference on Operational Technologies. He was also among the attendees at the first ever Def Con. He is known for extensive "rant" essays and speeches on technology and policy. He has also been a co-host on episodes of "Binary Revolution", as a cryptography expert.

Writing 
 "An open letter to PFIR on "Whois" privacy", Politech listserv, June 24, 2004
 "DNS WHOIS: Barking up the wrong tree", CircleID, June 28, 2004
 "The Road Ahead for Top-Level Domains", Vint Cerf answers three of Tom's questions in an interview, CircleID, March 13, 2006
 "Academic freedom and the hacker ethic", Communications of the ACM, June 2006.
 "Puppy smoothies: Improving the reliability of open, collaborative wikis", First Monday, September 2006.

References

External links 
 Decius's page at MemeStreams
 Binary Revolution
 Industrial Memetics Institute
 PhreakNIC technology conference
 MemeStreams Weblog Community

1976 births
Living people
American technology writers
Canadian expatriates in the United States
Scientists from Toronto
Writers from Toronto
Georgia Tech alumni
Computer security specialists
American computer scientists
People from Brentwood, Tennessee
DRMAA. Distributed Resource Management Application API (DRMAA) is a high-level Open Grid Forum (OGF) API specification for the submission and control of jobs to a distributed resource management (DRM) system, such as a cluster or grid computing infrastructure. The scope of the API covers all the high level functionality required for applications to submit, control, and monitor jobs on execution resources in the DRM system.

In 2007, DRMAA was one of the first two (the other one was GridRPC) specifications that reached the full recommendation status in the OGF.

In 2012 the second version of the DRMAA standard (DRMAA2) was published in an abstract interface definition language (IDL) defining the semantic of the functions in GFD 194. DRMAA2 specifies more than twice as many calls as DRMAA. It covers cluster monitoring, has a notion of queues and machines, and introduces a multi job-session concept for single applications for a better job workflow management. Later in 2012 the C API was specified as a first language binding in GF 198.

Development model 

The development of this API was done through the Global Grid Forum, in the model of IETF standard development, and it was originally co-authored by: 
Roger Brobst from Cadence Design Systems
Waiman Chan from IBM
Fritz Ferstl from Sun Microsystems, now Univa
Jeff Gardiner from John P. Robarts Research Institute
Andreas Haas from Sun Microsystems (Co-chair)
Bill Nitzberg from Altair Engineering
Hrabri Rajic from Intel (Maintainer & Co-chair)
John Tollefsrud from Sun Microsystems Founding (chair)

This specification was first proposed at Global Grid Forum 3 (GGF3) in Frascati, Italy, but gained most of its momentum at Global Grid Forum 4 in Toronto, Ontario. The development of the specification was first proposed with the objective to facilitate direct interfacing of applications to existing DRM systems by application's builders, portal builders, and Independent Software Vendors (ISVs). Because the API was co-authored by participants from a wide-selection of companies and included participants from industries and education, its development resulted in an open standard that received a relatively good reception from a wide audience quickly.

Significance 

Without DRMAA, no standard model existed to submit jobs to component regions of a Grid, assuming each region was running local DRMSs.  The first version of DRMAA API has been implemented in Sun's Grid Engine and also in the University of Wisconsin–Madison's program Condor.

References 

Distributed Resource Management Application API Specification 1
GGF3 Event List
GGF4 Event List

External links 
DRMAA's Project Page
Open Grid Forum
Condor Homepage
DRMAA binding for Platform LSF
Condor Extensions Project
DRMAA binding for Ruby
DRMAA HOWTOs and Tutorials

Grid computing
Open standards
CDDLM. CDDLM (Configuration Description, Deployment, and Lifecycle Management Specification) is a Global Grid Forum standard for the management, deployment and configuration of Grid Service lifecycles or inter-organization resources.

Structure 
The specification is based on component documents;
 Document that describes functional requirements, use cases, and high-level architectures, and otherwise serves as a Foundation Document
 Document outlining the development of a non-XML based Configuration, Description and Deployment Language
 Document outlining the development of an XML based Configuration, Description and Deployment Language
 Document outlining the development of a Configuration, Description and Deployment Component Model

Development Model 
The development of this API was done through the Global Grid Forum as an open standard, in the model of IETF standard development, and it was originally edited by D. Bell, T. Kojo, P. Goldsack, S. Loughran, D. Milojicic, S. Schaefer, J. Tatemura, and P. Toft.

Significance 
System administration in a distributed environment with diverse hardware, software, patch level, and imposed user requirements makes the ability to deploy, manage, and describe services and software configuration difficult. Within a grid, this difficulty is complicated further by the need to have similar service end points, possibly on heterogeneous architectures. Grid service requests may require configuration changes.

This standard provided a framework which described a language and methods that have the ability to describe system configuration, and move system, services, and software towards desired configuration endpoints. Furthermore, it served as the first real attempt to address system administration issues within a grid. CDDLM is to grids, as CFEngine for servers.

References 
 Global Grid Forum CDDLM document
 Global Grid Forum Document Series

External links 
 Global Grid Forum homepage
 System Administration and CDDLM
 Distributed Resource Management Application API

Grid computing
Rutan VariViggen. The Rutan VariViggen is a homebuilt aircraft designed by Burt Rutan.  The aircraft is a tandem two-seater of primarily wooden construction with a delta wing and a canard foreplane. The VariViggen is powered by a 150 hp Lycoming O-320 aero engine in pusher configuration. The prototype was designated Model 27, and the production version was Model 32.

Design and development

The VariViggen was named after the Swedish fighter plane, the Saab 37 Viggen. This and the XB-70 Valkyrie inspired the design. Rutan became interested in aircraft which resisted stalls and spins, and the VariViggen was his first full scale design. He began working with the design as a student at Cal Poly in the early 1960s, and started building the prototype in his garage in 1968. After four years of work, the aircraft made its first flight in April, 1972.  In order to increase efficiency, the Model 32 (also known as the VariViggen SP) had a slightly longer fuselage, a larger wingspan and winglets.

The Rutan Aircraft Factory sold 600 plan sets for the VariViggen to homebuilders, and eventually about 20 of the aircraft were built. Following the crash of one in New Brunswick, Canada in September 2006 due to wing tank fuel contamination, fewer than five are currently still flying. The prototype aircraft, N27VV, can be seen in the 1975 movie Death Race 2000 and was eventually donated to the EAA AirVenture Museum in 1988.

Rutan also began work on an all-aluminum variant, the MiniViggen, but later abandoned the project and focused his efforts on the VariEze.

VariViggen Model 27 Specifications (Standard Wing)

References

External links

 NZ website on the VariViggen
 Sun 'n Fun Air Museum 
 AirVenture Museum
 Museum of Flight VariViggen website
 Aerofiles VariViggen information
 Stargazer Website on VariViggen (models 27 & 32 information)
  Stargazer Website on Twin Turbojet powered VariViggen
 Stargazer Website on all metal VariViggen variant
 VariViggen History (Link Fixed 031921)

Aircraft first flown in 1972
Homebuilt aircraft
VariViggen
Canard aircraft
Delta-wing aircraft
Single-engined pusher aircraft
Low-wing aircraft
Segregationist (short story). "Segregationist" is a science fiction short story by American writer Isaac Asimov.  The story was written in April 1967 and was first published in December in Abbottempo, a magazine produced by Abbott Laboratories, then later included in the collections Nightfall and Other Stories (1969), The Complete Robot (1982) and Robot Visions (1990).

Plot summary
The story depicts a future where robotic prosthetics for humans and artificially-created organic body-parts for robots (known as Metallos) are commonplace. Metallos have been granted equal status with 'normal' humans.

A man, who has been granted the right to long life (possibly immortality) by an official Board of Mortality, meets the surgeon who is to assist in the performance of heart replacement surgery on the man. The surgeon offers him a choice between a metallic or fibrous cyber-heart. The man stubbornly refuses the doctor's attempts to persuade him to accept a fibrous heart, saying that it's "weak," as compared to a metal heart.

Later, the surgeon remarks to a medical engineer that he would rather that humans and robots stick to being what they are instead of becoming similar. The engineer calls such talk "segregationist", to which the surgeon replies that he "doesn't care." At the end of the story, the surgeon is revealed to be a robot himself.

Reception
In 1969, Analog Science Fiction / Science Facts P. Schuyler Miller called it "a beautifully tricky little short-short." In 1970, The Magazine of Fantasy & Science Fictions Joanna Russ reviewed Best SF: 1968 "[i]t leans toward the obvious and toward stories which have one good, clear, conventional idea" counting "Segregationist" among them.

References

External links 
 
 "Segregationist" on the Internet Archive

1967 short stories
American short stories
Robot series short stories by Isaac Asimov
Science fiction short stories
Segregation
Works originally published in American magazines
Works originally published in science and technology magazines
Dispensing ball. A dispensing ball is a special plastic ball used to dispense liquid fabric softener in clothes washing machines that lack built-in softener dispensers. Liquid fabric softener has to be added at the correct time to a load of laundry (the rinse cycle) in order to work effectively. In top-loading machines, the ball accomplishes this with no user input, other than the initial loading, and filling of the ball.

Operation

In a top-loading washing machine, the ball floats on the surface of the water during the mild forces of the washing process, and remains sealed. The stronger forces of the later spin cycle causes the seal on the ball to be broken, releasing the liquid softener.

These balls can not be used in front-loading tumbling washers, because the tumbling releases the fabric softener before the rinse cycle. They cannot be used at all in the dryer.

Downy Ball 

The Downy Ball is a variant sold by Procter & Gamble specifically designed for use with traditional agitator-based top-loading washing machines which lack built-in fabric softener dispensers, and it won't work correctly on front-loading machines. Liquid fabric softener is poured into the Downy Ball through a hole on the top side. The ball is then tossed into the washing machine with the clothes and detergent, where it floats in a vertical position, with an internal rubber weight floating inside and trapping the softener inside. In the spin cycle, between the wash and rinse cycles, the internal rubber weight moves aside due to Newton's first law of motion, allowing the fabric softener to spill out onto the clothes, just in time for the rinse cycle.

References

Cleaning products
Laundry washing equipment
Merz & McLellan. Merz and McLellan was a leading British electrical engineering consultancy based in Newcastle.

History
The firm was founded by Charles Merz and William McLellan in Newcastle upon Tyne in 1902 when McLellan joined Merz's existing firm established in 1899. The partnership was instrumental in designing the United Kingdom's first three-phase electrical supply network, on Tyneside, and for the next century continued to advise other Commonwealth countries on setting up their own networks.

In the early 1960s, Merz & McLellan started a scheme in the interest of reclaming land owned by the London Brick Company in Peterborough; James Price took up the position of senior resident engineer. This became known as the "Peterborough Dust Disposal Scheme".

In 1995 the partnership merged with the Parsons Brinckerhoff consultancy, and in 2000 the new owners announced that the Merz & McLellan name would be discontinued.

In 2010, Mott MacDonald consultancy announced that it had bought Merz and McLellan South Africa.

Selected contracts 
 1901: Neptune Bank Power Station
 1904: Carville Power Station, Wallsend, UK
 1908 & 1912: Electrification of Melbourne suburban railways in Victoria, Australia.
 1911: Electrification of North Eastern Railway (UK)
 1914-18: Mobile power stations for the battlefield
 1921: North Tees Power Station
 1925: Report on electrification of the New Zealand suburban systems in Auckland, Wellington, Christchurch and Dunedin. (including the Lyttelton railway line between Lyttelton and Christchurch
 1933-51: Dunston B power station, Dunston, Newcastle-Upon-Tyne, UK
 1940s: Orlando Power Station, Johannesburg, South Africa
 1950s: Kariba South dam power generators
 1950s: Wairakei Power Station Geothermal Power Station, New Zealand
 1953: Blyth A Power Station, Cambois, Northumberland, UK
 1960s: Bell Bay Power Station, Tasmania, Australia
 1962: Blyth B Power Station
 1967–76: Cerros Colorados Complex Plant Transmission System, Argentina
 1969: Longannet Power Station
 1980–1993: Kariba South dam hydroelectric upgrade
 1989: Subiya oil-fired power station, Kuwait

Merz & McLellan firms still independent 
 Sinclair Knight Merz (Australia)

References 

Electrical engineering companies of the United Kingdom
Companies based in Newcastle upon Tyne
Consulting firms established in 1902
British companies established in 1902
1902 establishments in England
Engineering consulting firms of the United Kingdom
Malaysian State Roads system. Malaysian State Roads System () are the secondary roads in Malaysia with a total length of 264,906.73 km (as of December 2023). The construction and maintenance works of state roads in Malaysia is managed by Malaysian Public Works Department (JKR) of each state and funded by state governments. The standard of the state roads is similar with the federal roads except for the coding system, where the codes for state roads begin with state codes followed by route number, for example Johor State Route J32 is labeled as J32. If a state road crosses the state border, the state code will change, for example route B20 in Salak Tinggi, Selangor will change to N20 after crossing the border of Negeri Sembilan to Nilai.

List of state codes in Malaysian State Roads system
The codes assigned to each state is the same as those of the car number plates except for Sabah.

A: 
B: 
C: 
D: 
J: 
K: 
M: 
N: 
P: 
R: 
SA: 
T: 
W :  (not used)
Q:

Municipal roads
Municipal roads are usually not given a route number, as they are maintained mainly by the local councils. An exception is some major roads in Shah Alam, the capital of Selangor. For example, Persiaran Raja Muda in Shah Alam was given route number BSA-3.

See also
 Road signs in Malaysia
 National Speed Limits
 Malaysian Expressway System
 Malaysian Federal Roads System

References

Malaysian Public Works Department
Roads in Malaysia
Scan chain. Scan chain is a technique used in design for testing.  The objective is to make testing easier by providing a simple way to set and observe every flip-flop in an IC. The basic structure of scan include the following set of signals in order to control and observe the scan mechanism.
 
Scan_in and scan_out define the input and output of a scan chain. In a full scan mode usually each input drives only one chain and scan out observe one as well.
A scan enable pin is a special signal that is added to a design. When this signal is asserted, every flip-flop in the design is connected into a long shift register.
Clock signal which is used for controlling all the flip-flops in the chain during shift phase and the capture phase.  An arbitrary pattern can be entered into the chain of flip-flops, and the state of every flip-flop can be read out.

In a full scan design, automatic test pattern generation (ATPG) is particularly simple.  No sequential pattern generation is required - combinatorial tests, which are much easier to generate, will suffice.  If you have a combinatorial test, it can be easily applied.
Assert scan mode, and set up the desired inputs.
De-assert scan mode, and apply one clock.  Now the results of the test are captured in the target flip-flops.
Re-assert scan mode, and see if the combinatorial test passed.

In a chip that does not have a full scan design -- i.e., the chip has sequential circuits, such as memory elements that are not part of the scan chain,  sequential pattern generation is required.
Test pattern generation for sequential circuits searches for a sequence of vectors to detect a particular fault through the space of all possible vector sequences.

Even a simple stuck-at fault requires a sequence of vectors for detection in a sequential circuit. Also, due to the presence of memory elements, the controllability and observability of the internal signals in a sequential circuit are in general much more difficult than those in a combinational logic circuit. These factors make the complexity of sequential ATPG much higher than that of combinational ATPG.

There are many variants:
Partial scan: Only some of the flip-flops are connected into chains.
Multiple scan chains: Two or more scan chains are built in parallel, to reduce the time to load and observe.
Test compression: the input to the scan chain is provided by on-board logic.

See also
Design for testing
Automatic test pattern generation
Electronic design automation
Integrated circuit design
Serial Peripheral Interface Bus
Iddq testing

External links 
An example of a scan chain for stuck-at faults

Electronic circuit verification
Fault coverage. Fault coverage refers to the percentage of some type of fault that can be detected during the test of any engineered system. High fault coverage is particularly valuable during manufacturing test, and techniques such as Design For Test (DFT) and automatic test pattern generation are used to increase it.

Applications

Digital electronics 
In digital electronics, fault coverage refers to stuck-at fault coverage. It is measured by sticking each pin of the hardware model at logic '0' and logic '1', respectively, and running the test vectors. If at least one of the outputs differs from what is to be expected, the fault is said to be detected. Conceptually, the total number of simulation runs is twice the number of pins (since each pin is stuck in one of two ways, and both faults should be detected). However, there are many optimizations that can reduce the needed computation. In particular, often many non-interacting faults can be simulated in one run, and each simulation can be terminated as soon as a fault is detected.

A fault coverage test passes when at least a specified percentage of all possible faults can be detected. If it does not pass, at least three options are possible. First, the designer can augment or otherwise improve the vector set, perhaps by using a more effective automatic test pattern generation tool. Second, the circuit may be re-defined for better fault detectability (improved controllability and observability). Third, the designer may simply accept the lower coverage.

See also 
Design for testing
Automatic test pattern generation
Electronic design automation
Fault detection and isolation

References

External links
 Gate-level fault simulator PROOFS for non-profit educational institutions from the University of Illinois
 Free, hierarchical fault simulator AUSIM from Auburn University

Electronic design
Electronic design automation
Electronic engineering
Integrated circuits