omniomni/omni-engineering huggingface dataset:
Slide calculator. A slide calculator, also known as an Addiator after the best-known brand, is a mechanical calculator capable of addition and subtraction, once made by Addiator Gesellschaft of Berlin, Germany. Variants of it were manufactured from 1920 until 1982. The devices were made obsolete by the electronic calculator.

Design 

The Addiator is composed of sheet-metal sliders inside a metal envelope, manipulated by a stylus, with an innovative carry mechanism, doing subtract ten, carry one with a simple stylus movement. Some types of Addiators can also handle negative numbers (with a complementary bottom window or by providing a subtraction mode on the back side of the device).

The Addiator also handles non-decimal measurements, like feet and inches, or pre-decimalization pounds, shillings, and pence. Addition and subtraction require different "screens", handled by turning the instrument over, or flipping a front panel, or, later, by extended sliders and an extra lower panel. Although not always advertised (e.g., the Magic Brain Calculator mentions "add, subtract, multiply" on its front plate), procedures exist for multiplication (by repeated addition or by individual digit multiplications) and division (e.g., by repeated subtraction, or use of additions combined with complementary numbers).

More expensive versions have a built-in slide rule on the back.

History 

Sometime between 1666 and 1675, French polymath Claude Perrault invented the first slide calculator, called Abaque rhabdologique (a rabdological abacus), when he needed to do a lot of calculations while working as an architect.

About three decades later, around 1700 or shortly after, French businessman and amateur mathematician César Caze simplified Perrault's design and adapted it to counting money, getting a privilege (patent) in 1711. However, neither of these devices implemented a carry mechanism.

In 1845, German musician and amateur mechanic Heinrich Kummer, who was living in St. Petersburg, saw a mechanical calculator of a different design made by Hayyim Selig Slonimski, and in the next year borrowed the idea of its carry mechanism to greatly improve Caze's device, leading to the modern variant of the slide calculator.

Addiator
In 1889, Louis-Joseph Troncet successfully commercialized the Addiator, which became one of the most popular calculators of its kind, and the name is often used to refer to the type generally.

Addiators appeared in newspaper advertisements as early as 1921, listed at a price of  in the Daily Record of Scotland. As of 1968, Addiators were advertised in American newspapers starting at $3.98 each .

See also

References

External links 

 'Addiator' type calculators at Vintage Calculators Web Museum
 Addiator museum
 Calculator museum
  Addiators and many other calculators (in German)
 Collection of calculating devices
 Addiator at Rechnerlexikon (in German)
 Addiator photos and manuals hosted at www.computercollector.com
 Addiator photos
 Addiator Hexadat Programmers Calculator
 A catalog showing photographs of dozens of different models
 Magic Brain: Last Gasp of the Mechanical Calculator via YouTube

Mechanical calculators
Options (novel). Options is a 1975 absurdist science fiction novel by American writer Robert Sheckley, published in paperback by Pyramid Books. The first British edition appeared in 1977, and a French translation was published in 1979.

The story is ostensibly about a marooned space traveller's attempt to get a spare part for his starship, the Intrepid III. He has a robotic guard, programmed to guard him against all planetary dangers. But soon he discovers that the robot has not been programmed for the planet where they are, with comic results. However, the narrative later descends into a mass of diversions, non-sequiturs and meditations on the nature of authorship. Eventually the diversions take over the book to the extent that the author openly introduces an increasingly bizarre succession of deus ex machina in an attempt to get the novel back on track, but eventually admits defeat.

Reception
Spider Robinson reviewed the novel favorably, declaring that although Sheckley deliberately broke most of the rules for successful storytelling, Options was "hilarious... an exploding cigarette, a velvet banana, a bearded tractor, a Presbyterian platypus."

Dave Langford reviewed Options for White Dwarf #86, and stated that "the author is 'unable' to construct a credible plot device to save the situation. Lots of fun but, for obvious reasons, not much plot."

References

External links 
 Reviews of most Sheckley's works
 A review

Novels by Robert Sheckley
1975 American novels
1975 science fiction novels
American science fiction novels
Metafictional novels
Postmodern novels
Comic science fiction novels
Pyramid Books books
James Dadford. James Dadford (born 1769) was an English canal engineer.

Career

He was engineer of the Gloucester and Berkeley Canal from 1795 to 1800.

His father Thomas Dadford, and brothers Thomas Dadford, Jr. and John Dadford were also canal engineers.

See also
Aberdare Canal
List of canal engineers
Canals of the United Kingdom
History of the British canal system

References

English canal engineers
1769 births
Year of death missing
18th-century English engineers
Berkut. Berkut may refer to:

 Asian golden eagle or berkut, a bird of prey
 Berkut (special police force), the former special units of the Ukrainian police and current units of the Russian Crimean police
 The Berkut, a 1987 novel by Joseph Heywood
 S-25 Berkut, a Russian surface-to-air missile system known to NATO as the SA-1 Guild
 Su-47 Berkut, a Russian experimental supersonic jet fighter developed by Sukhoi
 Berkut, a radar reported to be used on the Il-38 and Tu-142 aircraft for antisubmarine warfare
 Berkut 360, a US home-built delta wing canard aircraft of composite construction
 Berkut Air, an airline based in Almaty, Kazakhstan
 Berkut rifle, a semi-automatic hunting rifle designed and manufactured in Russia
 Berkut spacesuit, a Soviet space suit developed in 1964–1965
 Kresta I-class cruiser or Berkut, a surface warfare guided missile cruiser
 Kresta II-class cruiser or Berkut, an anti-submarine guided missile cruiser
 Berkut Group, a fictional organization in Bionic Woman
 Berkut, Russian oil platform in the Okhotsk Sea
 , a Russian helicopter
 HC Berkut, a Ukrainian professional ice hockey team
 HC Berkut-Kyiv, a Ukrainian ice hockey team from 1997 to 2002
 Berkut Stadium, a football stadium
 Berkut, an antagonist from Fire Emblem Echoes: Shadows of Valentia

People with the surname
 Arthur Berkut (born 1962), Russian singer
 Nataliya Berkut (born 1975), Ukrainian long-distance runner

See also
 Golden Eagle (disambiguation)
Simple Plastic Airplane Design. Simple Plastic Airplane Design (SPAD) is a type of radio controlled model airplane.

The R.C. aircraft is usually, though not always, built with the body consisting of a lightweight plastic material such as PVC gutter downspout or an aluminium rail. The wings are made of an equally light material such as foam or coroplast. The remaining components added to the plane are virtually the same as can be found in any other R.C. aircraft of similar size.

This concept of building simple radio controlled airplanes using cheap materials without the time-consuming and painstaking process of working with balsa wood and iron-on plastic coating was popularized by a web site created in the late 1990s, spadtothebone.net. While this web site, and the many original plans and articles still exist, the main gathering place for Spad enthusiasts on the web today resides at rcgroups..  R/C Report magazine author Frank Costa covered Spads from April 2003 to July 2004.

SPADs are preferred to other materials because they are cheaper and are easy to work with, painting is not required, the plastic can optionally be decorated with vinyl sheets which are available in any signboard making shop at very cheap price. The hinges for the control surfaces can be made by sheering one of the twinwalls of the plastic sheet and no special hinging device is required.

SPAD Modelers use corrugated plastic sheets of various thickness, such as 2 millimeter (like the flying wings  or electric gliders for which 2mm sheet are preferred) and 4 millimeter. These sheets are generally used by signboard makers and many times, when these sheets are discarded, the modelers have a choice to use them to build model airplanes.

The choice of propulsion can be either internal combustion engine or electric motors as with balsa counterparts.

Corrugated plastic planes are simpler alternative to the traditional balsa wood based R.C. aircraft for a variety of situations.  Most of the SPAD airplanes do not use balsa which saves considerable cost. They withstand crashes better than balsa counterparts because of their resilience and hence are a good choice for beginners. Good trainer planes and gliders can be made from SPADs. SPAD modelers make equally good advanced planes that can be made with corrugated plastic. They include: RC Airplane Combat, 3D Flying, and are preferred in places where the flyers would normally not risk a more expensive plane and yet want the same flying characteristics of balsa planes.

For making a SPAD plane, the modeler (usually a beginner) can copy the dimensions of a well known balsa trainer and makes the SPAD plane using the same dimensions and adapting to the building techniques of a SPAD plane. The plane can also be built from plans or can be scratch built (usually, the modeler draws his/her own plans and makes the plane, though this is mostly attempted by experienced modelers)

References

External links 
 spadtothebone.net - Home of the free SPAD plans
 spadworld.net SPAD forum home
 RC Groups - SPAD message forum
 RC Universe SPAD message forum
 SPAD Québec Ressources francophone pour les SPADs au Québec

Radio-controlled aircraft
Music On A Long Thin Wire. ″Music on a Long Thin Wire" is a musical piece by Alvin Lucier conceived in 1977.

In his own words (1992): "Music on a Long Thin Wire is constructed as follows: the wire is extended across a large room, clamped to tables at both ends. The ends of the wire are connected to the loudspeaker terminals of a power amplifier placed under one of the tables. A sine wave oscillator is connected to the amplifier. A magnet straddles the wire at one end. Wooden bridges are inserted under the wire at both ends to which contact microphones are embedded, routed to a stereo sound system. The microphones pick up the vibrations that the wire imparts to the bridges and are sent through the playback system. By varying the frequency and loudness of the oscillator, a rich variety of slides, frequency shifts, audible beats and other sonic phenomena may be produced."

However, Lucier admits a long thin wire was at first only used to avoid the look of a laboratory experiment in favour of a more sculptural appearance; a short thin wire would have worked as well. He discovered that the best way to produce variation in the sonic phenomena was to pick a setting and leave the setup alone. He praised David Rosenboom for his ability to pick interesting settings.

It has been exhibited:
1979, Winrock Shopping Center, Albuquerque, and broadcast uninterrupted on KUNM (FM) for five days and nights
1980, Landmark Center, Saint Paul
1988, Gallery of the Center for the Arts at Wesleyan, Middletown, CT
2011, Tom Duff was duplicating the 1979 performance from Albuquerque on sfSoundRadio, an internet radio station from the San Francisco bay area, again broadcasting uninterrupted for five days (April 8–12).
2013, Brno, Czech Republic, The Exposition of New Music Festival
2015, Dartmouth College, DAX: Dartmouth's Digital Arts Exhibition

See also
I Am Sitting in a Room, Lucier composition also based on resonance

Sources

External links

Compositions by Alvin Lucier
Process music pieces
SPAD. SPAD may refer to:

Science and technology
 Signal passed at danger by a train
 Simple Plastic Airplane Design, a type of radio-controlled model airplane
 Single-photon avalanche diode, a photodetector
 Single Pass Albumin Dialysis, liver dialysis

Military
 SPAD VII, SPAD S.XII and SPAD S.XIII, French fighter planes of World War I produced by Société Pour L'Aviation et ses Dérivés
 A-1 Skyraider, nicknamed Spad, an attack aircraft (1950s and 1960s)
 Self-propelled air defence, weapons

Other uses
 Société Pour L'Aviation et ses Dérivés, also Société Provisoire des Aéroplanes Deperdussin and Blériot-SPAD, French aircraft manufacturer (1912–1921)
 Special adviser (UK), a government post
 Suruhanjaya Pengangkutan Awam Darat, the Land Public Transport Commission of Malaysia

See also
 Spade (disambiguation)
Return-to-libc attack. A "return-to-libc" attack is a computer security attack usually starting with a buffer overflow in which a subroutine return address on a call stack is replaced by an address of a subroutine that is already present in the process executable memory, bypassing the no-execute bit feature (if present) and ridding the attacker of the need to inject their own code. The first example of this attack in the wild was contributed by Alexander Peslyak on the Bugtraq mailing list in 1997.

On POSIX-compliant operating systems the C standard library ("libc") is commonly used to provide a standard runtime environment for programs written in the C programming language. Although the attacker could make the code return anywhere, libc is the most likely target, as it is almost always linked to the program, and it provides useful calls for an attacker (such as the system function used to execute shell commands).

Protection from return-to-libc attacks
A non-executable stack can prevent some buffer overflow exploitation, however it cannot prevent a return-to-libc attack because in the return-to-libc attack only existing executable code is used. On the other hand, these attacks can only call preexisting functions. Stack-smashing protection can prevent or obstruct exploitation as it may detect the corruption of the stack and possibly flush out the compromised segment.

"ASCII armoring" is a technique that can be used to obstruct this kind of attack. With ASCII armoring, all the system libraries (e.g., libc) addresses contain a NULL byte (0x00). This is commonly done by placing them in the first 0x01010101 bytes of memory (a few pages more than 16 MB, dubbed the "ASCII armor region"), as every address up to (but not including) this value contains at least one NULL byte. This makes it impossible to emplace code containing those addresses using string manipulation functions such as strcpy(). However, this technique does not work if the attacker has a way to overflow NULL bytes into the stack. If the program is too large to fit in the first 16 MB, protection may be incomplete. This technique is similar to another attack known as return-to-plt where, instead of returning to libc, the attacker uses the Procedure Linkage Table (PLT) functions loaded in the position-independent code (e.g., system@plt, execve@plt, sprintf@plt, strcpy@plt).

Address space layout randomization (ASLR) makes this type of attack extremely unlikely to succeed on 64-bit machines as the memory locations of functions are random. For 32-bit systems, however, ASLR provides little benefit since there are only 16 bits available for randomization, and they can be defeated by brute force in a matter of minutes.

See also
 Buffer overflow
 Stack buffer overflow
 Stack-smashing protection
 No eXecute (NX) bit 
 Address space layout randomization
 Return-oriented programming
 Gadget (machine instruction sequence)
 Unintended instructions

References

External links
 Bypassing non-executable-stack during exploitation using return-to-libc by c0ntex at css.csail.mit.edu

Computer security exploits
C standard library
Spool. Spool may refer to:
Bobbin, a cylinder or reel on which a quantity of thread, yarn or wire is wound for use in a particular machine or device
Cable reel, used to carry various types of electrical wires
Spool (record label), active 1998–2008
Spool (software company), a software company that allows users to save video and text onto their mobile devices to view the content offline
Spool pin, a type of pin used in pin tumbler locks to prevent picking
Simultaneous Peripheral Operation On-Line, Spooling, a form of multi-programming for the purpose of copying data between different devices
The Spooler, an operating system enhancement that provided spooling facilities for some IBM computers
Spool (aeronautics), the unit of rotating components inside a jet engine
Spooling up, increasing RPMs and thrust in a jet engine after the throttle has been advanced
Spool, a device used in differentials
Winch
Hoist (device)
AD Flying Boat. The AD Flying Boat was designed by the British Admiralty's Air Department to serve as a patrol aircraft that could operate in conjunction with Royal Navy warships. Intended for use during the First World War, production of the aircraft was terminated as the end of the war came into sight, and the type saw little operational use. A number were repurchased after the end of the war by Supermarine Aviation and rebuilt as civil transports, becoming known as the Supermarine Channel.

Design and development
Designed in 1915 by the British yacht designer Linton Hope, the aircraft was of conventional biplane flying-boat configuration, and also featured a biplane tail with twin fins and rudders. The pilot and observer sat in tandem in the nose, with the engine and pusher propeller mounted behind them, between the wings. The wings could be folded forwards to facilitate shipboard stowage.

Two prototypes were constructed in 1916 by Pemberton-Billing Ltd (later to become Supermarine Aviation Works). The first prototype was intended to be powered by a 150 hp (112 kW) Sunbeam Nubian engine, but as this was not ready to use, a  Hispano-Suiza 8 was substituted. The aircraft performed poorly both on the water and in the air, demonstrating severe fore and aft vibration during take-off, while subject to excessive yaw during flight. After these problems were solved by producing revised versions of the hull, and the fin and rudder, the AD Flying Boat was able to be ordered into production. A total of 80 aircraft were ordered, and 27 machines were built. Examples were tested with Sunbeam Arab and Wolseley Python engines.

Supermarine Channel

Following the Armistice, Supermarine purchased 19 of these AD Flying Boats to modify them for the civil market as the Supermarine Channel. The Channel I was powered with a  Beardmore 160 hp engines, and the Channel II was fitted with a  Armstrong Siddeley Puma engine. The reconfigured flying-boats provided accommodation for a pilot and three passengers in three open cockpits.

Operators

Military operators
 
Chilean Air Force - One aircraft.
Chilean Navy acquired one Channel with modified hull (similar to the Supermarine Seal II) in 1922.
 
Imperial Japanese Navy purchased three Channels.
 
 Royal Norwegian Navy Air Service purchased four Beardmore engined Channels in 1920, acquiring a further ex-civil aircraft. One remained in service until 1928. 
 
 Royal Swedish Navy purchased a single Channel in 1921, it being destroyed during testing.
 
 Royal Navy
 Royal Naval Air Service operated AD Flying Boat.

Civil operators
 
 Det Norske Luftfartsrederi, Channel Mk I

Specifications (AD Flying Boat)

See also
 Sempill Mission

References

Sources

 
 
 
 

Flying Boat
1910s British patrol aircraft
Single-engined pusher aircraft
Flying boats
Supermarine aircraft
Biplanes
Aircraft first flown in 1916
87 Helicopter Flying School SAAF. 87 Helicopter Flying School is a unit of the South African Air Force. It is a helicopter flight training school.

The Helicopter Conversion Unit was established at Ysterplaat on 1 February 1968 to fulfill the helicopter pilot and flight engineers training role. The present unit was formed on 9 April 1968 by redesignating Training Flight, 17 Squadron at AFB Ysterplaat. The unit, equipped with Alouette II and III's, took over responsible for Helicopter Conversion Training of SAAF pilots and training of Flight Engineers for the SAAF.

The Helicopter Conversion Unit became an autonomous unit in 1971 and in January 1973 the units name changed to 87 Advanced Flying School. In 1973 the Alouette II's were retired and transferred to the Rhodesian Air Force. "B" Flight, 16 Squadron, also stationed at AFB Ysterplaat, took responsibility for advanced helicopter training from 16 September 1974 to January 1975.

References

Squadrons of the South African Air Force
Military units and formations in Bloemfontein
Flying Training Schools of air forces
Educational institutions established in 1973
1973 establishments in South Africa
S-VT. S-VT, or Sequential Valve Timing, is an automobile variable valve timing technology developed by Mazda. S-VT varies the timing of the intake valves by using hydraulic pressure to rotate the camshaft. S-VT was introduced in 1998 on the ZL-VE engine and is used in the B-, Z-, MZR- and J-families of engines.

See also
 Variable valve timing

Variable valve timing
Mazda Technologies
Stoddard-Hamilton Aircraft. Stoddard-Hamilton Aircraft, based in Arlington, Washington, was a designer and supplier of high-performance homebuilt aircraft kits, offering parts and plans to homebuilders. The company's popular Glasair aircraft series are low wing, two-seat (side by side) fiberglass designs.

The Glasair TD of 1979 was the first pre-molded composite aircraft kit on the general aviation market, introduced at the 1980 EAA Oshkosh Airshow. The company was started by Tom Hamilton and named, tongue in cheek, after the style of large aircraft manufacturers in the United States. Using Hamilton's middle and last name, the company was incorporated as Stoddard-Hamilton.

Retractable gear and up-engined models were later introduced, with the Glasair III Turbo capable of speeds in excess of , and another model being fitted with a turboprop engine. In the mid-1990s, Glasair introduced the Glastar, a high-wing, short-field capable utility aircraft with two seats.

In 2001, Thomas W. Wathen purchased the assets of the Glasair from bankrupt Stoddard-Hamilton Aircraft. He combined New Glasair LLC with New GlaStar LLC and continued production of the Glasair and GlaStar kits at the Arlington factory, marketing them under the Glasair Aviation name.

Aircraft
 SH-1 Prototype
 Glasair I
 Glasair II
 Glasair III
 Glastar
 T-9 Stalker

References

External links

Defunct aircraft manufacturers of the United States
Arlington, Washington
MOS Technology 6509. The MOS Technology 6509, an enhanced version of the popular 6502 microprocessor, is capable of addressing up to 1 megabyte of RAM via bank switching. While numerous 6502-based processors can perform bank switching, they achieve this via separate logic. The 6509 has this logic on-chip.

Passing data between different banks requires use of the register at $1 which selects the banks to be read from and written to via LDA (zero page), Y and STA (zero page), Y CPU opcodes. The register at $0 selects the bank where the CPU fetches instructions from, which will default to 15 ($F) on power up.

The 6509 has a reputation for being difficult to program, due to its bank switching scheme. It is used in the Commodore CBM-II line of computers.

References

Further reading

External links
MOS 6509 datasheet (GIF format, zipped)
MOS 6509 datasheet (PDF format)

65xx microprocessors
MOS Technology microprocessors
8-bit microprocessors