omniomni/omni-engineering huggingface dataset:
PDP-15. The PDP-15 was the fifth and last of the 18-bit minicomputers produced by Digital Equipment Corporation.  The PDP-1 was first delivered in December 1959 and the first PDP-15 was delivered in February 1970. More than 400 of these successors to the PDP-9 (and 9/L) were ordered within the first eight months.

In addition to operating systems, the PDP-15 has compilers for Fortran and ALGOL.

History
The 18-bit PDP systems preceding the PDP-15 were named PDP-1, PDP-4, PDP-7 and PDP-9.
The last PDP-15 was produced in 1979.

Hardware

The PDP-15 was DEC's only 18-bit machine constructed from TTL integrated circuits rather than discrete transistors, and, like every DEC 18-bit system could be equipped with:
 an optional X-Y (point-plot or vector graphics) display.
 a hardware floating-point option, with a 10x speedup.
 up to 128K words of core main memory

Models
The PDP-15 models offered by DEC were:
 PDP-15/10: a 4K-word paper-tape-based system
 PDP-15/20: 8K, added DECtape
 PDP-15/30: 16K word, added memory protection and a foreground/background monitor
 PDP-15/35: Added a 524K-word fixed-head disk drive
 PDP-15/40: 24K memory
 PDP-15/50:

PDP-15/76
 PDP-15/76: 15/40 plus PDP-11 frontend. The PDP-15/76 was a dual-processor system that shared memory with an attached PDP-11/05. The PDP-11 served as a peripheral processor and enabled use of  Unibus peripherals.

Software
DECsys, RSX-15, and XVM/RSX were the operating systems supplied by DEC for the PDP-15. A batch processing monitor (BOSS-15: Batch Operating Software System) was also available.

DECsys
The first DEC-supplied mass-storage operating system available for the PDP-15 was DECsys, an interactive single-user system. This software was provided on a DECtape reel, of which copies were made for each user.  This copied DECtape was then added to by the user, and thus was storage
for personal programs and data.  A second DECtape was used as a scratch tape by the assembler and the Fortran compiler.

RSX-15 
RSX-15 was released by DEC in 1971. The main architect for RSX-15 (later renamed XVM/RSX) was Dennis "Dan" Brevik.

Once XVM/RSX was released, DEC facilitated that "a PDP-15 can be field-upgraded to XVM" but it required "the addition of the XM15 memory processor."

The RSX-11 operating system began as a port of RSX-15 to the PDP-11, although it later diverged significantly in terms of design and functionality.

Origin of the RSX-15 name
Commenting on the RSX acronym, Brevik says:

XVM/RSX
Later versions of the PDP-15 could run a real-time multi-user OS called XVM/RSX, an outgrowth of RSX-15. The XVM upgrade to RSX was multi-user, and enabled up to six concurrent teletype-based users. XVM Support for the PDP-15/76 included using an RK05 disk drive.

non-DEC
The MUMPS operating system, which was originally developed in 1966, was developed on the PDP-7 outside DEC. It is also available for the PDP-15.

Application software
DEC provided mathematical, scientific and commercial software application tools.

See also
 Programmed Data Processor

References

External links
 a diary re PDP-15 & RSX-15

DEC minicomputers
18-bit computers
Transistorized computers
Computer-related introductions in 1970
British Westinghouse. British Westinghouse Electrical and Manufacturing Company was a subsidiary of the Pittsburgh, US-based Westinghouse Electric and Manufacturing Company. British Westinghouse would become a subsidiary of Metropolitan-Vickers in 1919; and after Metropolitan-Vickers merged with British Thomson-Houston in 1929, it became part of Associated Electrical Industries (AEI) in 1959. Further consolidation saw AEI taken over by GEC in 1967.

Establishment
George Westinghouse established British Westinghouse in 1899 with capital from his own company and a smaller share from UK investors. The company commenced the construction of its first factory in Trafford Park, Manchester the same year. Manufacturing began in 1902, the same year as the rival British Thomson-Houston (BTH). BTH was majority owned by General Electric and the competition between BTH and British Westinghouse mirrored that of the parent companies, GE and Westinghouse in America. The Belgian electrical engineer, Paul Mossay, worked for BTH in the period 19021906 developing induction motors. Then in 1906 he started working for British Westinghouse, creating even larger motors.

Receivership
In 1907 Westinghouse USA went into receivership with the result that executive control of the company was taken away from George Westinghouse, though he remained as president. Another effect of this was the increased independence of British Westinghouse. This was reinforced in 1910 when the board voted to remove George Westinghouse from his role as chairman. American Westinghouse retained over half the shares.

World War I
In 1916 British Westinghouse, following the impression that American control of the company hindered its performance during World War I, began the transition to a British owned company. Metropolitan Carriage Wagon Company bought a controlling interest in the group in 1917. The same year the board accepted a merger with Vickers and the name Metropolitan-Vickers was chosen. Vickers assumed control in 1919 when Metropolitan Carriage was sold to the company.

Products
Products included gas engines, steam engines, electric generators, transformers, switchgear, meters, motors, control gear, and arc lamps. During World War I, British Westinghouse built some small petrol-electric locomotives for the War Department Light Railways. Similar locomotives were built by Dick, Kerr & Co.

References

External links

Defunct manufacturing companies of the United Kingdom
Electrical engineering companies of the United Kingdom
Former defence companies of the United Kingdom
Westinghouse Electric Company
Metropolitan-Vickers
Manufacturing companies established in 1899
1899 establishments in the United Kingdom
Managed code. Managed code is computer program code that requires and will execute only under the management of a Common Language Infrastructure (CLI); Virtual Execution System (VES); virtual machine, e.g. .NET, CoreFX, or .NET Framework; Common Language Runtime (CLR); or Mono. The term was coined by Microsoft.

Managed code is the compiler output of source code written in one of over twenty high-level programming languages, including C#, J# and Visual Basic .NET.

Terminology
The true and fine distinction between managed and unmanaged code is prevalent and only relevant when developing applications that interact with CLR implementations. Since many older programming languages have been ported to the CLR, the differentiation is needed to identify managed code, especially in a mixed setup. In this context, code that does not rely on the CLR is termed "unmanaged".

A source of confusion was created when Microsoft started connecting the .NET Framework with C++, and the choice of how to name the Managed Extensions for C++. It was first named Managed C++ and then renamed to C++/CLI. The creator of the C++ programming language and member of the C++ standards committee, Bjarne Stroustrup, even commented on this issue, "On the difficult and controversial question of what the CLI binding/extensions to C++ is to be called, I prefer C++/CLI as a shorthand for 'The CLI extensions to ISO C++'. Keeping C++ as part of the name reminds people what is the base language and will help keep C++ a proper subset of C++ with the C++/CLI extensions."

Uses
The Microsoft Visual C++ compiler can produce both managed code, running under CLR, or unmanaged binaries, running directly on Windows.

Benefits of using managed code include programmer convenience (by increasing the level of abstraction, creating smaller models) and enhanced security guarantees, depending on the platform (including the VM implementation). There are many historical examples of code running on virtual machines, such as the language UCSD Pascal using p-code, and the operating system Inferno from Bell Labs using the Dis virtual machine. Java popularized this approach with its bytecode executed by the Java virtual machine.

Google also mention that Java and Kotlin are managed code in their Android NDK JNI documents

References

External links
Microsoft Research OS written in managed C# code, Channel 9

.NET terminology
Catchwater drain. A catchwater drain is a land drain, a ditch cut across the fall of the land, typically just above the level of low-lying, level ground such as The Fens of eastern England, where some land, tens of kilometres from the sea is at about sea level. Its purpose is to gather water draining from the higher, sloping ground before it reaches the flat land  whence it would be difficult or expensive to remove.  The water may be on the surface, in streams or in the ground before it is gathered, perhaps to be led away across the lowland by an embanked river. 

There are other circumstances in which a catchwater may be employed.  A hill-top or hillside may be used to trap rainwater which is then gathered by the catchwater and fed to a reservoir. From this a house, village or town may be supplied. Catchwater may be used to slow down runoff before running on impervious surfaces to reduce runoff.

See also
Nullah

References

Land management
Momentum theory. In fluid dynamics, momentum theory or disk actuator theory is a theory describing a mathematical model of an ideal actuator disk, such as a propeller or helicopter rotor, by W.J.M. Rankine (1865), Alfred George Greenhill (1888) and Robert Edmund Froude (1889).

The rotor is modeled as an infinitely thin disc, inducing a constant velocity along the axis of rotation. The basic state of a helicopter is hovering. This disc creates a flow around the rotor. Under certain mathematical premises of the fluid, there can be extracted a mathematical connection between power, radius of the rotor, torque and induced velocity. Friction is not included.

For a stationary open rotor with no outer duct, such as a helicopter in hover, the power required to produce a given thrust is:

where:
 T is the thrust
  is the density of air (or other medium)
 A is the area of the rotor disc
 P is power

A device which converts the translational energy of the fluid into rotational energy of the axis or vice versa is called a Rankine disk actuator. The real life implementations of such devices include marine and aviation propellers, windmills, helicopter rotors, centrifugal pumps, wind turbines, turbochargers and chemical agitators.

See also
 Blade element theory
 Circulation (fluid dynamics)
 Disk loading
 Kutta–Joukowski theorem

References

Fluid dynamics
Propellers
Momentum
Aircraft aerodynamics
Elbe Air. Elbe Air Lufttransport GmbH, usually just known as Elbe Air, was a corporate charter airline from Germany, which offered worldwide on-demand flight services. The company was headquartered in Büren, Westphalia and had its operational base at nearby Paderborn Lippstadt Airport.

History
In 2002, Elbe Air operated a fleet of three Dassault Falcon 20 jets. In the same year, reports surfaced about poor safety and security standards with the airline. A former pilot had filed a report with the German Federal Aviation Office, concerning poorly trained pilots and ageing aircraft, which had not been properly maintained.

The airline filed for bankruptcy and was liquidated in 2008.

References

Defunct airlines of Germany
Airlines established in 1995
Airlines disestablished in 2008
German companies disestablished in 2008
German companies established in 1995
Digital. Digital usually refers to something using discrete digits, often binary digits.

Businesses
Digital bank, a form of financial institution
Digital Equipment Corporation (DEC) or Digital, a computer company
Digital Research (DR or DRI), a software company

Computing and technology

Hardware
Digital electronics, electronic circuits which operate using digital signals
Digital camera, which captures and stores digital images 
Digital versus film photography
Digital computer, a computer that handles information represented by discrete values
Digital recording, information recorded using a digital signal

Socioeconomic phenomena
Digital culture, the anthropological dimension of the digital social changes
Digital divide, a form of economic and social inequality in access to or use of information and communication technologies
Digital economy, an economy based on computing and telecommunications resources
Digital rights, legal rights of access to computers or the Internet

Other uses in computing and technology
Digital data, discrete data, usually represented using binary numbers
Digital marketing, search engine and social media marketing
Digital media, media stored as digital data
Digital radio, which uses digital technology to transmit or receive
Digital television, television systems which broadcast using digital signals
Digital signal (electronics), signals formed from a discrete set of waveforms, rather than continuous ranges
Digital signal (signal processing), sampled analog signals represented as a sequence of digital values

Entertainment and media

Music
Digital (album), an album by KRS-One
"Digital" (Goldie song) (1998)
"Digital" (Joy Division song) (1978)
"Digital (Did You Tell)", a song by Stone Sour (2010)
"Digital", a song by Alexandra Stan from Unlocked
"Digital", a song by Imagine Dragons from Origins
"Digital", a song by Soulja Boy from The DeAndre Way
"Digital", a song by T-Pain from Three Ringz

Other media
Digital: A Love Story (2010), an indie video game by Christine Love
Digital painting, a method of creating visual art using computers

Other uses
Relating to the fingers
Digital exam, in proctology
Digital Party, a political party in Uruguay
Vitalis Takawira or Digital, professional football player

See also
Digit (disambiguation)
Digital download (disambiguation)
Digital fingerprint (disambiguation)
Binary code
Boolean algebra
:Category:Digital media
Differential thermal analysis. Differential thermal analysis (DTA) is a thermoanalytic technique that is similar to differential scanning calorimetry. In DTA, the material under study and an inert reference are made to undergo identical thermal cycles, (i.e., same cooling or heating programme) while recording any temperature difference between sample and reference. This differential temperature is then plotted against time, or against temperature (DTA curve, or thermogram). Changes in the sample, either exothermic or endothermic, can be detected relative to the inert reference. Thus, a DTA curve provides data on the transformations that have occurred, such as glass transitions, crystallization, melting and sublimation. The area under a DTA peak is the enthalpy change and is not affected by the heat capacity of the sample.

Apparatus
A DTA consists of a sample holder, thermocouples, sample containers and a ceramic or metallic block; a furnace; a temperature programmer; and a recording system. The key feature is the existence of two thermocouples connected to a voltmeter. One thermocouple is placed in an inert material such as Al2O3, while the other is placed in a sample of the material under study. As the temperature is increased, there will be a brief deflection of the voltmeter if the sample is undergoing a phase transition. This occurs because the input of heat will raise the temperature of the inert substance, but be incorporated as latent heat in the material changing phase. It consist of inert environment with inert gases which will not react with sample and reference. Generally helium or argon is used as inert gas.

Today's instruments
In today's market most manufacturers don't make true DTA systems but rather have incorporated this technology into thermogravimetric analysis (TGA) systems, which provide both mass loss and thermal information. With today's advancements in software, even these instruments are being replaced by true TGA-DSC instruments that can provide the temperature and heat flow of the sample, simultaneously with mass loss.

Applications
A DTA curve can be used only as a finger print for identification purposes but usually the applications of this method are the determination of phase diagrams, heat change measurements and decomposition in various atmospheres.

DTA is widely used in the pharmaceutical and food industries.

DTA may be used in cement chemistry, mineralogical research and in environmental studies.

DTA curves may also be used to date bone remains or to study archaeological materials.
Using DTA one can obtain liquidus & solidus lines of phase diagrams.

References

Analytical chemistry
Scientific techniques
Low rate initial production. Low rate initial production (LRIP) is a term commonly used in military weapons projects and programs to designate the phase of initial, small-quantity production. The term is also applied in fields other than weapons production, most commonly in non-weapon military equipment programs.

With LRIP, the prospective first buyer and operator (i.e., a country's defense authorities and the relevant military units) can thoroughly test the weapons system over some protracted amount of time in order to gain a reasonable degree of confidence as to whether the system actually performs to the agreed-upon requirements before contracts for mass production are signed. At the same time, manufacturers can use the LRIP as a production test phase in which they develop the assembly line models that would eventually be used in mass production. Therefore, the LRIP is commonly the first step in transitioning from highly customized, hand-built prototypes to the final mass-produced end product. 

In practice, either the production capability or the weapons system itself can be unready during the LRIP phase. This can mean that systems produced during LRIP are built significantly differently both in terms of technique and cost owing to the immaturity of the production line or changes in the weapons system's design, necessitating a large degree of hand assembly and trial and error typically associated with the prototyping stage.  Furthermore, the cost of each LRIP system can be much greater than the final mass production unit cost, since the LRIP cost can include both the R&D and setup cost for production, although the goal is for this additional cost to be  spread out over future production carried out by the assembly capacity developed during LRIP.

Immaturity in a system's design or its method of production discovered during LRIP phase can result in additional LRIP phases to verify corrections and improvements, or project cancellation. The Congressional Budget Office has found that the United States Department of Defense rarely achieves projected cost savings because too many programs fail to move from LRIP to full-scale production. The Japanese Ministry of Defense similarly lists R&D and initial production as "high-risk phases" in a 2008 report.

References

Military terminology
Arms industry
Production and manufacturing
Integrated device manufacturer. An integrated device manufacturer (IDM) is a semiconductor company which designs, manufactures, and sells integrated circuit (IC) products.

IDM is often used to refer to a company which handles semiconductor manufacturing in-house, compared to a fabless semiconductor company, which outsources production to a third-party semiconductor fabrication plant.

Examples of IDMs are Intel, Samsung, and Texas Instruments, examples of fabless companies are AMD, Nvidia, Qualcomm, and Zhaoxin, and examples of pure play foundries are GlobalFoundries, TSMC, and UMC.

Due to the dynamic nature of the semiconductor industry, the term IDM has become less accurate than when it was coined.

OSATs
The term OSATs means "outsourced semiconductor assembly and test providers". OSATs have dominated IC packaging and testing.

Fabless operations

The terms fabless (fabrication-less), foundry, and IDM are now used to describe the role a company has in a business relationship. For example, Freescale owns and operates fabrication facilities (fab) where it manufactures many chip product lines, as a traditional IDM would. Yet it is known to contract with merchant foundries for other products, as would fabless companies.

Manufacturers
Many electronic manufacturing companies engage in business that would qualify them as an IDM:

 Analog Devices (and previously Maxim Integrated Products)
 ams AG

 Changxin Memory Technologies
 CR Microelectronics
 Fujitsu
 Good-Ark Electronics
 Hitachi
 IBM (was integrated, up to 2015, then fabless)
 Infineon (previously Cypress Semiconductor)
 Intersil (now subsidiary of Renesas)
 Intel
 LSI Corporation (aquired, not part of fabless Broadcom)
 Matsushita
 Micron Technology (and previously IM Flash Technologies)
 Mitsubishi
 National Semiconductor (became part of Texas Instruments)
 Nexperia
 NXP (formerly Philips + Freescale Semiconductors)
 OMMIC
 ON Semiconductor
 
 Qorvo
 Renesas (formerly NEC semiconductor)
 Samsung
 Shanghai Belling 
 SK Hynix
 STMicroelectronics
 Sony
 Texas Instruments
 Tsinghua Unigroup
 Toshiba
 https://www.belling.com.cn/en/about.html Shanghai Belling GlenDimplex
 Yangtze Memory Technologies

Reading 
 Understanding fabless IC technology By Jeorge S. Hurtarte, Evert A. Wolsheimer, Lisa M. Tafoya 1.4.1 Integrated device manufacturer Page 8

References

Semiconductor device fabrication
Autofac. "Autofac" is a 1955 science fiction novelette by American writer Philip K. Dick that features one of the earliest treatments of self-replicating machines (and Dick's second, after his 1953 novelette Second Variety). It appeared originally in Galaxy Science Fiction of November 1955, and was reprinted in several collections, including The Variable Man published in 1957, and Robots, Androids, and Mechanical Oddities published in 1984.

It was adapted by Travis Beacham for an episode of the 2017 TV series, Philip K. Dick's Electric Dreams, with the same name as the short story.

Plot summary
Three men wait outside their settlement for an automated delivery truck. Five years earlier, during the Total Global Conflict, a network of hardened automatic factories ("autofacs") had been set up with cybernetic controls that determine what food and consumer goods to manufacture and deliver. Human input had been lost, and the men planned disruption to try to establish communication and take over control. They destroy the delivery, but the truck radios the autofac and unloads an identical replacement, then prevents them from reloading items. They act out being disgusted with the milk delivery and are given a complaints checklist. In a blank space, they write improvised semantic garble—"the product is thoroughly pizzled". The autofac sends a humanoid data collector that communicates on an oral basis but is not capable of conceptual thought, and they are unable to persuade the network to shut down before it consumes all resources. Their next strategy sets neighbouring autofacs in competition with each other for rare resources and succeeds in creating military conflict between the autofacs. After the autofac conflict seems to be resolved, the men explore the ruins of a destroyed autofac to see if there are any industrial machines that can be salvaged. They locate a hidden level. Inside they find that the factory is self-replicated, and sending out "metal seeds" configured to make miniature autofacs.

Translations
French: "Le Règne des robots", anonymous, August 1956, in "Galaxie Anticipation" issue 33

Television version
The TV series Philip K. Dick's Electric Dreams includes a one-hour episode based on the story, with considerable differences in the plot and outcome.

References

External links
"Autofac" at the Internet Archive

Short stories by Philip K. Dick
1955 short stories
Self-replicating machines in fiction
Post-apocalyptic short stories
Short stories about robots