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The failure or fracture of a product or component as a result of a single event is known as mechanical overload. It is a common failure mode. The terms are used in forensic engineering and structural engineering when analysing product failure | https://huggingface.co/datasets/fmars/wiki_stem |
301 Mission Street is a high-rise residential building in the South of Market district of downtown San Francisco. A mixed-use, primarily residential high rise, it is the tallest residential building and the 6th-tallest overall in San Francisco. In May 2016, residents were informed the main tower was both sinking and tilting, resulting in several lawsuits concerning repair costs and whether the tilt had been withheld from buyers | https://huggingface.co/datasets/fmars/wiki_stem |
A mission critical factor of a system is any factor (component, equipment, personnel, process, procedure, software, etc. ) that is essential to business operation or to an organization. Failure or disruption of mission critical factors will result in serious impact on business operations or upon an organization, and even can cause social turmoil and catastrophes | https://huggingface.co/datasets/fmars/wiki_stem |
Over the latter years of the 19th and early years of the 20th centuries, Penistone in Yorkshire gained a name as an accident black-spot on Britain's railway network; indeed, it could be said to hold the title of the worst accident black-spot in the country. The main line through the town was the Woodhead route of the Manchester, Sheffield and Lincolnshire Railway between Sheffield Victoria and Manchester, London Road. The line was heavily graded with a summit some 400 yards inside the eastern portal of the Woodhead tunnel | https://huggingface.co/datasets/fmars/wiki_stem |
In telecommunication, the term power failure transfer has the following meanings:
The switching of primary utilities to their secondary backup whenever the primary source operates outside its design parameters. This is accomplished via a transfer switch.
In telephony, a function which, when activated in the event of a commercial power failure or a low-voltage battery condition at a subscriber location, supplies power to predesignated subscriber equipment via the central office trunk | https://huggingface.co/datasets/fmars/wiki_stem |
In materials science and solid mechanics, residual stresses are stresses that remain in a solid material after the original cause of the stresses has been removed. Residual stress may be desirable or undesirable. For example, laser peening imparts deep beneficial compressive residual stresses into metal components such as turbine engine fan blades, and it is used in toughened glass to allow for large, thin, crack- and scratch-resistant glass displays on smartphones | https://huggingface.co/datasets/fmars/wiki_stem |
The Salton Sea is a shallow, landlocked, highly saline body of water in Riverside and Imperial counties at the southern end of the U. S. state of California | https://huggingface.co/datasets/fmars/wiki_stem |
A single point of failure (SPOF) is a part of a system that, if it fails, will stop the entire system from working. SPOFs are undesirable in any system with a goal of high availability or reliability, be it a business practice, software application, or other industrial system.
Overview
Systems can be made robust by adding redundancy in all potential SPOFs | https://huggingface.co/datasets/fmars/wiki_stem |
Stress corrosion cracking (SCC) is the growth of crack formation in a corrosive environment. It can lead to unexpected and sudden failure of normally ductile metal alloys subjected to a tensile stress, especially at elevated temperature. SCC is highly chemically specific in that certain alloys are likely to undergo SCC only when exposed to a small number of chemical environments | https://huggingface.co/datasets/fmars/wiki_stem |
Structural integrity and failure is an aspect of engineering that deals with the ability of a structure to support a designed structural load (weight, force, etc. ) without breaking and includes the study of past structural failures in order to prevent failures in future designs.
Structural integrity is the ability of an item—either a structural component or a structure consisting of many components—to hold together under a load, including its own weight, without breaking or deforming excessively | https://huggingface.co/datasets/fmars/wiki_stem |
A system accident (or normal accident) is an "unanticipated interaction of multiple failures" in a complex system. This complexity can either be of technology or of human organizations and is frequently both. A system accident can be easy to see in hindsight, but extremely difficult in foresight because there are simply too many action pathways to seriously consider all of them | https://huggingface.co/datasets/fmars/wiki_stem |
The Westinghouse J40 was an early high-performance afterburning turbojet engine designed by Westinghouse Aviation Gas Turbine Division starting in 1946 to a US Navy Bureau of Aeronautics (BuAer) request. BuAer intended to use the design in several fighter aircraft and a bomber. However, while an early low-power design was successful, attempts to scale it up to its full design power failed, and the design was finally abandoned, deemed a "fiasco" and a "flop" | https://huggingface.co/datasets/fmars/wiki_stem |
Videx, Inc. , is a Corvallis, Oregon manufacturer of computer hardware such as access control products and data collection terminals. It was founded in 1979 by Paul Davis | https://huggingface.co/datasets/fmars/wiki_stem |
nPar partitions are electrically isolated from other nPar partitions within the same chassis. Cells (a unit of processors/IO/memory) make up nPar partitions. Being electrically isolated means that if a nPar partition were to fail due to hardware failure, then the other nPar partitions would continue to work | https://huggingface.co/datasets/fmars/wiki_stem |
A logical partition (LPAR) is a subset of a computer's hardware resources, virtualized as a separate computer. In effect, a physical machine can be partitioned into multiple logical partitions, each hosting a separate instance of an operating system.
PR/SM
Formally, LPAR designates the mode of operation or an individual logical partition, whereas PR/SM is the commercial designation of the feature | https://huggingface.co/datasets/fmars/wiki_stem |
A network partition is a division of a computer network into relatively independent subnets, either by design, to optimize them separately, or due to the failure of network devices. Distributed software must be designed to be partition-tolerant, that is, even after the network is partitioned, it still works correctly.
For example, in a network with multiple subnets where nodes A and B are located in one subnet and nodes C and D are in another, a partition occurs if the network switch device between the two subnets fails | https://huggingface.co/datasets/fmars/wiki_stem |
In engineering and its various subdisciplines, acceptance testing is a test conducted to determine if the requirements of a specification or contract are met. It may involve chemical tests, physical tests, or performance tests. In systems engineering, it may involve black-box testing performed on a system (for example: a piece of software, lots of manufactured mechanical parts, or batches of chemical products) prior to its delivery | https://huggingface.co/datasets/fmars/wiki_stem |
Analog signature analysis is electronic component and circuit board troubleshooting technique which applies a current-limited AC sinewave across two points of an electronic component or circuit.
The resulting current/voltage waveform is shown on a signature display using vertical deflection for current and horizontal deflection for voltage. This unique analog signature represents the overall health of the part being analyzed | https://huggingface.co/datasets/fmars/wiki_stem |
Analog verification is a methodology for performing functional verification on analog, mixed-signal and RF integrated circuits and systems on chip. Discussion of analog verification began in 2005 when it started to become recognized that the analog portion of large mixed-signal chips had become so complex that a significant and ever-increasing number of these chips were being designed with functional errors in the analog portion that prevented them from operating correctly.
Technical details
Analog verification is built on the idea that transistor-level simulation will always be too slow to provide adequate functional verification | https://huggingface.co/datasets/fmars/wiki_stem |
Automated optical inspection (AOI) is an automated visual inspection of printed circuit board (PCB) (or LCD, transistor) manufacture where a camera autonomously scans the device under test for both catastrophic failure (e. g. missing component) and quality defects (e | https://huggingface.co/datasets/fmars/wiki_stem |
Automated X-ray inspection (AXI) is a technology based on the same principles as automated optical inspection (AOI). It uses X-rays as its source, instead of visible light, to automatically inspect features, which are typically hidden from view.
Automated X-ray inspection is used in a wide range of industries and applications, predominantly with two major goals:
Process optimization, i | https://huggingface.co/datasets/fmars/wiki_stem |
Automatic test equipment or automated test equipment (ATE) is any apparatus that performs tests on a device, known as the device under test (DUT), equipment under test (EUT) or unit under test (UUT), using automation to quickly perform measurements and evaluate the test results. An ATE can be a simple computer-controlled digital multimeter, or a complicated system containing dozens of complex test instruments (real or simulated electronic test equipment) capable of automatically testing and diagnosing faults in sophisticated electronic packaged parts or on wafer testing, including system on chips and integrated circuits.
Where it is used
ATE is widely used in the electronic manufacturing industry to test electronic components and systems after being fabricated | https://huggingface.co/datasets/fmars/wiki_stem |
Bead probe technology (BPT) is technique used to provide electrical access (called “nodal access”) to printed circuit board (PCB) circuitry for performing in-circuit testing (ICT). It makes use of small beads of solder placed onto the board's traces to allow measuring and controlling of the signals using a test probe. This permits test access to boards on which standard ICT test pads are not feasible due to space constraints | https://huggingface.co/datasets/fmars/wiki_stem |
Black-box testing is a method of software testing that examines the functionality of an application without peering into its internal structures or workings. This method of test can be applied virtually to every level of software testing: unit, integration, system and acceptance. It is sometimes referred to as specification-based testing | https://huggingface.co/datasets/fmars/wiki_stem |
Burn-in is the process by which components of a system are exercised before being placed in service (and often, before the system being completely assembled from those components). This testing process will force certain failures to occur under supervised conditions so an understanding of load capacity of the product can be established.
The intention is to detect those particular components that would fail as a result of the initial, high-failure rate portion of the bathtub curve of component reliability | https://huggingface.co/datasets/fmars/wiki_stem |
In electronics, a continuity test is the checking of an electric circuit to see if current flows (that it is in fact a complete circuit).
A continuity test is performed by placing a small voltage (wired in series with an LED or noise-producing component such as a piezoelectric speaker) across the chosen path. If electron flow is inhibited by broken conductors, damaged components, or excessive resistance, the circuit is "open" | https://huggingface.co/datasets/fmars/wiki_stem |
A debug port is a chip-level diagnostic interface (akin to a computer port) included in an integrated circuit to aid design, fabrication, development, bootstrapping, configuration, debugging, and post-sale in-system programming. In general terms, a debug port is not necessary for end-use function and is often hidden or disabled in finished products.
When constituted in a high availability or safety critical system, a debug port may continue to operate as a system monitor for integrity validation in the finished product | https://huggingface.co/datasets/fmars/wiki_stem |
Design for testing or design for testability (DFT) consists of IC design techniques that add testability features to a hardware product design. The added features make it easier to develop and apply manufacturing tests to the designed hardware. The purpose of manufacturing tests is to validate that the product hardware contains no manufacturing defects that could adversely affect the product's correct functioning | https://huggingface.co/datasets/fmars/wiki_stem |
A device under test (DUT), also known as equipment under test (EUT) and unit under test (UUT), is a manufactured product undergoing testing, either at first manufacture or later during its life cycle as part of ongoing functional testing and calibration checks. This can include a test after repair to establish that the product is performing in accordance with the original product specification.
Electronics testing
In the electronics industry a DUT is any electronic assembly under test | https://huggingface.co/datasets/fmars/wiki_stem |
Enterprise test software (ETS) is a type of software that electronics and other manufacturers use to standardize product testing enterprise-wide, rather than simply in the test engineering department. It is designed to integrate and synchronize test systems to other enterprise functions such as research and development (R&D), new product introduction (NPI), manufacturing, and supply chain, overseeing the collaborative test processes between engineers and managers in their respective departments.
Details
Like most enterprise software subcategories, ETS represents an evolution away from custom-made, in-house software development by original equipment manufacturers (OEM) | https://huggingface.co/datasets/fmars/wiki_stem |
Environmental stress screening (ESS) refers to the process of exposing a newly manufactured or repaired product or component (typically electronic) to stresses such as thermal cycling and vibration in order to force latent defects to manifest themselves by permanent or catastrophic failure during the screening process. The surviving population, upon completion of screening, can be assumed to have a higher reliability than a similar unscreened population.
Overview
Developed to help electronics manufacturers detect product defects and production flaws, ESS is widely used in military and aerospace applications, less so for commercial products | https://huggingface.co/datasets/fmars/wiki_stem |
An ESD simulator, also known as an ESD gun, is a handheld unit used to test the immunity of devices to electrostatic discharge (ESD). These simulators are used in special electromagnetic compatibility (EMC) laboratories. ESD pulses are fast, high-voltage pulses created when two objects with different electrical charges come into close proximity or contact | https://huggingface.co/datasets/fmars/wiki_stem |
The final quality audit (FQA) process, in the electronic hardware manufacturing world, is the last process flow before shipping a product. This process is established to ensure the unit has gone through and passed all the manufacturing or test process and is in good quality.
This process not only includes visual checking of the unit (i | https://huggingface.co/datasets/fmars/wiki_stem |
In the manufacture of electronic printed circuit boards, flying probes are used for testing both bare circuit boards and boards loaded with components. Flying probes were introduced in the late 1980’s. Flying probes can be found in many manufacturing and assembly operations | https://huggingface.co/datasets/fmars/wiki_stem |
Functional testing in manufacturing (FCT) is a test typically performed during the last phase of the production line. This is often referred to as a final quality control test, which is done to ensure that specifications are carried out by FCTs.
The process of FCTs is entailed by the emulation or simulation of the environment in which a product is expected to operate | https://huggingface.co/datasets/fmars/wiki_stem |
Gray-box testing (International English spelling: grey-box testing) is a combination of white-box testing and black-box testing. The aim of this testing is to search for the defects, if any, due to improper structure or improper usage of applications.
Overview
A black-box tester is unaware of the internal structure of the application to be tested, while a white-box tester has access to the internal structure of the application | https://huggingface.co/datasets/fmars/wiki_stem |
A stress test (sometimes called a torture test) of hardware is a form of deliberately intense and thorough testing used to determine the stability of a given system or entity. It involves testing beyond normal operational capacity, often to a breaking point, in order to observe the results.
Reasons can include: to determine breaking points and safe usage limits; to confirm that the intended specifications are being met; to determine modes of failure (how exactly a system may fail), and to test stable operation of a part or system outside standard usage | https://huggingface.co/datasets/fmars/wiki_stem |
In-circuit testing (ICT) is an example of white box testing where an electrical probe tests a populated printed circuit board (PCB), checking for shorts, opens, resistance, capacitance, and other basic quantities which will show whether the assembly was correctly fabricated. It may be performed with a "bed of nails" test fixture and specialist test equipment, or with a fixtureless in-circuit test setup.
Fixtures for in-circuit testing
A common form of in-circuit testing uses a bed-of-nails tester | https://huggingface.co/datasets/fmars/wiki_stem |
Inquisitor is a software suite used for hardware diagnostics, stress testing, certification and benchmarking platform. It is available in three formats:
Standalone – As a package to be installed into existing Linux installation; such practice is somewhat limited in available tests.
Live – Distributed as a Linux live CD distribution; system under test should be booted from it; this way one particular system can be tested thoroughly | https://huggingface.co/datasets/fmars/wiki_stem |
Integration testing (sometimes called integration and testing, abbreviated I&T) is the phase in software testing in which the whole software module is tested or if it consists of multiple software modules they are combined and then tested as a group. Integration testing is conducted to evaluate the compliance of a system or component with specified functional requirements. It occurs after unit testing and before system testing | https://huggingface.co/datasets/fmars/wiki_stem |
JTAG (named after the Joint Test Action Group which codified it) is an industry standard for verifying designs and testing printed circuit boards after manufacture.
JTAG implements standards for on-chip instrumentation in electronic design automation (EDA) as a complementary tool to digital simulation. It specifies the use of a dedicated debug port implementing a serial communications interface for low-overhead access without requiring direct external access to the system address and data buses | https://huggingface.co/datasets/fmars/wiki_stem |
Within the field of electronics Level-sensitive scan design (LSSD) is part of an integrated circuit manufacturing test process. It is a DFT scan design method which uses separate system and scan clocks to distinguish between normal and test mode. Latches are used in pairs, each has a normal data input, data output and clock for system operation | https://huggingface.co/datasets/fmars/wiki_stem |
Mixed flowing gas (MFG) is a type of laboratory environmental testing for products, particularly electronics, to evaluate resistance to corrosion due to gases in the atmosphere. Mixed Flowing Gas (MFG) test is a laboratory test in which the temperature (°C), relative humidity (%RH), concentration of gaseous pollutants (in parts per billion, ppb or parts per million ppm level), and other critical variables (such as volume exchange rate and airflow rate) are carefully defined, monitored and controlled. The purpose of this test is to simulate corrosion phenomenon due to atmospheric exposure | https://huggingface.co/datasets/fmars/wiki_stem |
Negative-bias temperature instability (NBTI) is a key reliability issue in MOSFETs, a type of transistor aging. NBTI manifests as an increase in the threshold voltage and consequent decrease in drain current and transconductance of a MOSFET. The degradation is often approximated by a power-law dependence on time | https://huggingface.co/datasets/fmars/wiki_stem |
The ongoing reliability test (ORT) is a hardware test process usually used in manufacturing to ensure that quality of the products is still of the same specifications as the day it first went to production or general availability.
The products currently in the manufacturing line are randomly picked every day with a predefined percentage or numbers and then put in a control drop tower or an environmental chamber. Control drop simulates physical interactions on the product, while environmental chamber simulates the stress profile of thermal cycling, elevated temperature, or combined environmental stresses to induce fatigue damage | https://huggingface.co/datasets/fmars/wiki_stem |
Programmable Built-In Self-Test (PBIST) is a memory DFT feature that incorporates all the required test systems into the chip itself. The test systems implemented on-chip are as follows:
algorithmic address generator
algorithmic data generator
program storage unit
loop control mechanismsPBIST was originally adopted by large memory chips that have high pin counts and operate at high frequencies, thereby exceeding the capability of production testers.
The purpose of PBIST is to avoid developing and buying more sophisticated and very expensive testers | https://huggingface.co/datasets/fmars/wiki_stem |
A probe card (commonly referred to as a DUT board) is used in automated integrated circuit testing. It is an interface between an electronic test system and a semiconductor wafer.
Use and manufacture
A probe card or DUT board is a printed circuit board (PCB), and is the interface between the integrated circuit and a test head, which in turn attaches to automatic test equipment (ATE) (or "tester") | https://huggingface.co/datasets/fmars/wiki_stem |
Product intelligence is defined as an automated system for gathering and analyzing intelligence about the performance of a product being designed and manufactured, such that this data is automatically fed back to the product managers and engineers designing the product, to assist them in the development of the next iteration or version of that product. The goal of product intelligence is to accelerate the rate of product innovation, thereby making the product and its owners more competitive and increasing customer satisfaction. Product intelligence is often applied to electronic products, but it is not necessarily limited to electronic products | https://huggingface.co/datasets/fmars/wiki_stem |
A programmable load is a type of test equipment or instrument which emulates DC or AC resistance loads normally required to perform functional tests of batteries, power supplies or solar cells. By virtue of being programmable, tests like load regulation, battery discharge curve measurement and transient tests can be fully automated and load changes for these tests can be made without introducing switching transient that might change the measurement or operation of the power source under test.
Implementation
Programmable loads most commonly use one transistor/FET, or an array of parallel connected transistors/FETs for more current handling, to act as a variable resistor | https://huggingface.co/datasets/fmars/wiki_stem |
System testing is testing conducted on a complete integrated system to evaluate the system's compliance with its specified requirements. System testing takes, as its input, all of the integrated components that have passed integration testing. The purpose of integration testing is to detect any inconsistencies between the units that are integrated together (called assemblages) | https://huggingface.co/datasets/fmars/wiki_stem |
A test engineer is a professional who determines how to create a process that would best test a particular product in manufacturing and related disciplines, in order to assure that the product meets applicable specifications. Test engineers are also responsible for determining the best way a test can be performed in order to achieve adequate test coverage. Often test engineers also serve as a liaison between manufacturing, design engineering, sales engineering and marketing communities as well | https://huggingface.co/datasets/fmars/wiki_stem |
A testbed (also spelled test bed) is a platform for conducting rigorous, transparent, and replicable testing of scientific theories, computing tools, and new technologies.
The term is used across many disciplines to describe experimental research and new product development platforms and environments. They may vary from hands-on prototype development in manufacturing industries such as automobiles (known as "mules"), aircraft engines or systems and to intellectual property refinement in such fields as computer software development shielded from the hazards of testing live | https://huggingface.co/datasets/fmars/wiki_stem |
TestStand is a test management software suite from National Instruments. TestStand is used to develop test software for products which are produced by an enterprise. The test station has a similar appearance to test personnel across the product line | https://huggingface.co/datasets/fmars/wiki_stem |
A USB Killer is a device that is designed to be portable and sends high-voltage power surges repeatedly into the data lines of the device it is connected to, which will damage hardware components on unprotected devices. The device has been designed to test components for protection from power surges and electrostatic discharge.
Mechanism
The device typically contains several capacitors and charge and discharge circuitry | https://huggingface.co/datasets/fmars/wiki_stem |
White-box testing (also known as clear box testing, glass box testing, transparent box testing, and structural testing) is a method of software testing that tests internal structures or workings of an application, as opposed to its functionality (i. e. black-box testing) | https://huggingface.co/datasets/fmars/wiki_stem |
The history of computing hardware starting at 1960 is marked by the conversion from vacuum tube to solid-state devices such as transistors and then integrated circuit (IC) chips. Around 1953 to 1959, discrete transistors started being considered sufficiently reliable and economical that they made further vacuum tube computers uncompetitive. Metal–oxide–semiconductor (MOS) large-scale integration (LSI) technology subsequently led to the development of semiconductor memory in the mid-to-late 1960s and then the microprocessor in the early 1970s | https://huggingface.co/datasets/fmars/wiki_stem |
The 2N696 and 2N697 were the first silicon transistors manufactured in Silicon Valley, in 1958, by Fairchild Semiconductor. Fairchild introduced itself to the world via its advertisements for these transistors, which were identical except for a post-manufacturing binning on current gain. The 2N696/2N697 NPN mesa transistor was developed by a team led by Gordon Moore | https://huggingface.co/datasets/fmars/wiki_stem |
The 74181 is a 4-bit slice arithmetic logic unit (ALU), implemented as a 7400 series TTL integrated circuit. Introduced by Texas Instruments in February 1970, it was the first complete ALU on a single chip. It was used as the arithmetic/logic core in the CPUs of many historically significant minicomputers and other devices | https://huggingface.co/datasets/fmars/wiki_stem |
Code: The Hidden Language of Computer Hardware and Software (1999) is a book by Charles Petzold that seeks to teach how personal computers work at a hardware and software level. In the preface to the 2000 softcover edition, Petzold wrote that his goal was for readers to understand how computers work at a concrete level that "just might even rival that of electrical engineers and programmers" and that he "went as far back" as he could go in regard to the history of technological development. Petzold describes Code as being structured as moving "up each level in the hierarchy" in which computers are constructed | https://huggingface.co/datasets/fmars/wiki_stem |
In physics and electrical engineering, a coincidence circuit or coincidence gate is an electronic device with one output and two (or more) inputs. The output activates only when the circuit receives signals within a time window accepted as at the same time and in parallel at both inputs. Coincidence circuits are widely used in particle detectors and in other areas of science and technology | https://huggingface.co/datasets/fmars/wiki_stem |
The history of computer clusters is best captured by a footnote in Greg Pfister's In Search of Clusters: "Virtually every press release from DEC mentioning clusters says ‘DEC, who invented clusters. . | https://huggingface.co/datasets/fmars/wiki_stem |
The Cromemco Cyclops, introduced in 1975 by Cromemco, was the first commercial all-digital camera using a digital metal–oxide–semiconductor (MOS) image sensor. It was also the first digital camera to be interfaced to a microcomputer. The digital sensor for the camera was a modified 1 kb dynamic RAM (DRAM) memory chip that offered a resolution of 32 × 32 pixels (0 | https://huggingface.co/datasets/fmars/wiki_stem |
DECtape, originally called Microtape, is a magnetic tape data storage medium used with many Digital Equipment Corporation computers, including the PDP-6, PDP-8, LINC-8, PDP-9, PDP-10, PDP-11, PDP-12, and the PDP-15. On DEC's 32-bit systems, VAX/VMS support for it was implemented but did not become an official part of the product lineup.
DECtapes are 3⁄4 inch (19 mm) wide, and formatted into blocks of data that can each be read or written individually | https://huggingface.co/datasets/fmars/wiki_stem |
Disk packs and disk cartridges were early forms of removable media for computer data storage, introduced in the 1960s.
Disk pack
A disk pack is a layered grouping of hard disk platters (circular, rigid discs coated with a magnetic data storage surface). A disk pack is the core component of a hard disk drive | https://huggingface.co/datasets/fmars/wiki_stem |
The history of computing hardware in the Eastern Bloc is somewhat different from that of the Western world. As a result of the CoCom embargo, computers could not be imported on a large scale from Western Bloc.
Eastern Bloc manufacturers created copies of Western designs based on intelligence gathering and reverse engineering | https://huggingface.co/datasets/fmars/wiki_stem |
A floppy disk is a disk storage medium composed of a disk of thin and flexible magnetic storage medium encased in a rectangular plastic carrier. It is read and written using a floppy disk drive (FDD). Floppy disks were an almost universal data format from the 1970s into the 1990s, used for primary data storage as well as for backup and data transfers between computers | https://huggingface.co/datasets/fmars/wiki_stem |
The history of general-purpose CPUs is a continuation of the earlier history of computing hardware.
1950s: Early designs
In the early 1950s, each computer design was unique. There were no upward-compatible machines or computer architectures with multiple, differing implementations | https://huggingface.co/datasets/fmars/wiki_stem |
In materials science, a composite laminate is an assembly of layers of fibrous composite materials which can be joined to provide required engineering properties, including in-plane stiffness, bending stiffness, strength, and coefficient of thermal expansion.
The individual layers consist of high-modulus, high-strength fibers in a polymeric, metallic, or ceramic matrix material. Typical fibers used include cellulose, graphite, glass, boron, and silicon carbide, and some matrix materials are epoxies, polyimides, aluminium, titanium, and alumina | https://huggingface.co/datasets/fmars/wiki_stem |
A composite plate is basically a plate made out of composite materials, i. e. a resin and a fibre | https://huggingface.co/datasets/fmars/wiki_stem |
Composite repairs are performed on damaged laminate structures, fibre reinforced composites and other composite materials. The bonded composite repair reduces stresses in the damaged region and prevents cracks from opening or growing. Composite materials are used in a wide range of applications in aerospace, marine, automotive, surface transport and sports equipment markets | https://huggingface.co/datasets/fmars/wiki_stem |
A conductive elastomer is a form of elastomer, often natural rubber or other rubber substitute, that is manufactured to conduct electricity. This is commonly accomplished by distributing carbon or other conductive particles throughout the raw material prior to setting it. Carbon black and silica are common additives to induce conductivity in elastomers | https://huggingface.co/datasets/fmars/wiki_stem |
Consuta was a form of construction of watertight hulls for boats and marine aircraft, comprising four veneers of mahogany planking interleaved with waterproofed calico and stitched together with copper wire. The name is from the latin for "sewn together". The technique was patented by Sam Saunders of Goring-on-Thames and was first used on the 1898 umpire's steam launch of the same name | https://huggingface.co/datasets/fmars/wiki_stem |
Copper-clad steel (CCS), also known as copper-covered steel or the trademarked name Copperweld is a bi-metallic product, mainly used in the wire industry that combines the high mechanical strength of steel with the conductivity and corrosion resistance of copper.
It is mainly used for grounding purposes, line tracing to locate underground utilities, drop wire of telephone cables, and inner conductor of coaxial cables, including thin hookup cables like RG-174 and CATV cable. It is also used in some antennas for RF conducting wires | https://huggingface.co/datasets/fmars/wiki_stem |
Cross-laminated timber (CLT) is a subcategory of engineered wood with panel product made from gluing together at least three layers of solid-sawn lumber (i. e. lumber cut from a single log) | https://huggingface.co/datasets/fmars/wiki_stem |
Decorative laminates are laminated products primarily used as furniture surface materials or wall paneling. It can be manufactured as either high- or low-pressure laminate, with the two processes not much different from each other except for the pressure applied in the pressing process. Also, laminate can be produced either in batches or in a continuous process; the latter is called continuous pressure laminate (CPL) | https://huggingface.co/datasets/fmars/wiki_stem |
Delamination is a mode of failure where a material fractures into layers. A variety of materials including laminate composites and concrete can fail by delamination. Processing can create layers in materials such as steel formed by rolling and plastics and metals from 3D printing which can fail from layer separation | https://huggingface.co/datasets/fmars/wiki_stem |
Dental compomers, also known as polyacid-modified resin composite, are used in dentistry as a filling material. They were introduced in the early 1990s as a hybrid of two other dental materials, dental composites and glass ionomer cement, in an effort to combine their desirable properties: aesthetics for dental composites (they are white and closely mimic tooth tissue, so can camouflage into a tooth very well) and the fluoride releasing ability for glass ionomer cements (helps to prevent further tooth decay).
History
Compomers were introduced in the early 1990s | https://huggingface.co/datasets/fmars/wiki_stem |
Dental composite resins (better referred to as "resin-based composites" or simply "filled resins") are dental cements made of synthetic resins. Synthetic resins evolved as restorative materials since they were insoluble, of good tooth-like appearance, insensitive to dehydration, easy to manipulate and inexpensive. Composite resins are most commonly composed of Bis-GMA and other dimethacrylate monomers (TEGMA, UDMA, HDDMA), a filler material such as silica and in most applications, a photoinitiator | https://huggingface.co/datasets/fmars/wiki_stem |
Drywall (also called plasterboard, dry lining, wallboard, sheet rock, gib board, gypsum board, buster board, turtles board, slap board, custard board, and gypsum panel) is a panel made of calcium sulfate dihydrate (gypsum), with or without additives, typically extruded between thick sheets of facer and backer paper, used in the construction of interior walls and ceilings. The plaster is mixed with fiber (typically paper, glass wool, or a combination of these materials); plasticizer, foaming agent; and additives that can reduce mildew, flammability, and water absorption.
In the mid-20th century, drywall construction became prevalent in North America as a time- and labor-saving alternative to lath and plaster | https://huggingface.co/datasets/fmars/wiki_stem |
Electronic Beam curing (EBC) is a surface curing process in the manufacture of high pressure laminate (HPL) boards. The process applies color to a single sheet of Kraft paper which is adhered to a HPL board in such a way that it will keep its color durably while remaining scratch-resistant. Unlike other HPL creation methods, EBC does not use heat | https://huggingface.co/datasets/fmars/wiki_stem |
Electroshapable materials are composite materials from the class of thermoplastic materials. Electroshapable materials are plastics rigid at room temperature, which can take the form of various objects or plastic elements. They can substitute for more common thermoplastic polymers such as PVC, PE, PC, EVA | https://huggingface.co/datasets/fmars/wiki_stem |
Engineered stone is a composite material made of crushed stone bound together by an adhesive to create a solid surface, (most commonly polymer resin, with some newer versions using cement mix). This category includes engineered quartz (SiO2), polymer concrete and engineered marble stone. The application of these products depends on the original stone used | https://huggingface.co/datasets/fmars/wiki_stem |
Engineered wood, also called mass timber, composite wood, man-made wood, or manufactured board, includes a range of derivative wood products which are manufactured by binding or fixing the strands, particles, fibres, or veneers or boards of wood, together with adhesives, or other methods of fixation to form composite material. The panels vary in size but can range upwards of 64 by 8 feet (19. 5 by 2 | https://huggingface.co/datasets/fmars/wiki_stem |
Fiber pull-out is one of the failure mechanisms in fiber-reinforced composite materials. Other forms of failure include delamination, intralaminar matrix cracking, longitudinal matrix splitting, fiber/matrix debonding, and fiber fracture. The cause of fiber pull-out and delamination is weak bonding | https://huggingface.co/datasets/fmars/wiki_stem |
Fiber volume ratio is an important mathematical element in composite engineering. Fiber volume ratio, or fiber volume fraction, is the percentage of fiber volume in the entire volume of a fiber-reinforced composite material. When manufacturing polymer composites, fibers are impregnated with resin | https://huggingface.co/datasets/fmars/wiki_stem |
A fiber-reinforced cementitious matrix (FRCM) is a reinforcement system composed by fibers (such as steel, aramid, basalt, carbon, polyparaphenylenebenzobisoxazole, and glass) embedded in an inorganic-based matrix, usually made by cement or lime mortar. In international literature, FRCMs are also called textile-reinforced concrete (TRC), textile reinforced mortars (TRM), fabric-reinforced mortar (FRM), or inorganic matrix-grid composites (IMG). Starting from the second decade of the 21th century they are used for the structural rehabilitation of existing buildings, in particular made by masonry (existing and historical) or by reinforced concrete, to increase their load-bearing capacity under both vertical and horizontal loads (including seismic ones) | https://huggingface.co/datasets/fmars/wiki_stem |
Fiber-reinforced concrete or fibre-reinforced concrete (FRC) is concrete containing fibrous material which increases its structural integrity. It contains short discrete fibers that are uniformly distributed and randomly oriented. Fibers include steel fibers, glass fibers, synthetic fibers and natural fibers – each of which lend varying properties to the concrete | https://huggingface.co/datasets/fmars/wiki_stem |
Fiberglass sheet laminating is the process of taking a thin fiberglass sheet and laminating it to another material in order to provide strength and support to that material.
Process characteristics
Fiberglass is composed of very fine strands of glass. It has many different purposes, one of which is used for strength | https://huggingface.co/datasets/fmars/wiki_stem |
Fibre cement is a composite building and construction material, used mainly in roofing and facade products because of its strength and durability. One common use is in fiber cement siding on buildings.
Material description
The term "cement" originates from the Latin word "Caementum", which signifies chopped stone | https://huggingface.co/datasets/fmars/wiki_stem |
Foamcore, foam board, or paper-faced foam board is a lightweight and easily cut material used for mounting of photographic prints, as backing for picture framing, for making scale models, and in painting. It consists of a board of polystyrene foam clad with an outer facing of paper on either side, typically white clay-coated paper or brown kraft paper.
History
The original white foamcore board was made in 1⁄8-and-3⁄16-inch (3 | https://huggingface.co/datasets/fmars/wiki_stem |
Forged composite, commonly referred to as forged carbon, is a type of carbon fiber SMC material composed of small pieces of carbon fiber composite material that are pressed into shape as the resin sets. This is in contrast to most carbon fiber composites, which are made of larger continuous layers that are 'laid up' one at a time, often manually. Forged composite allows for a higher range of shapes to be formed with precision, relative to traditional carbon fiber | https://huggingface.co/datasets/fmars/wiki_stem |
FR-2 (Flame Resistant 2) is a NEMA designation for synthetic resin bonded paper, a composite material made of paper impregnated with a plasticized phenol formaldehyde resin, used in the manufacture of printed circuit boards. Its main properties are similar to NEMA grade XXXP (MIL-P-3115) material, and can be substituted for the latter in many applications.
Applications
FR-2 sheet with copper foil lamination on one or both sides is widely used to build low-end consumer electronic equipment | https://huggingface.co/datasets/fmars/wiki_stem |
In materials science Functionally Graded Materials (FGMs) may be characterized by the variation in composition and structure gradually over volume, resulting in corresponding changes in the properties of the material. The materials can be designed for specific function and applications. Various approaches based on the bulk (particulate processing), preform processing, layer processing and melt processing are used to fabricate the functionally graded materials | https://huggingface.co/datasets/fmars/wiki_stem |
Gelcoat or gel coat is a material used to provide a high-quality finish on the visible surface of a fibre-reinforced composite. The most common gelcoats are thermosetting polymers based on epoxy or unsaturated polyester resin chemistry. Gelcoats are modified resins which are applied to moulds in the liquid state | https://huggingface.co/datasets/fmars/wiki_stem |
Geopolymer bonded wood composite (GWC) are similar and a green alternatives to cement bonded wood composites. These products are composed of geopolymer binder, wood fibers/ wood particles. Depending on the wood and geopolymer ratio in the material, the properties of the wood-geopolymer composite material vary | https://huggingface.co/datasets/fmars/wiki_stem |
Glare (derived from GLAss REinforced laminate ) is a fiber metal laminate (FML) composed of several very thin layers of metal (usually aluminum) interspersed with layers of S-2 glass-fiber pre-preg, bonded together with a matrix such as epoxy. The uni-directional pre-preg layers may be aligned in different directions to suit predicted stress conditions.
Though Glare is a composite material, its material properties and fabrication are very similar to bulk aluminum metal sheets | https://huggingface.co/datasets/fmars/wiki_stem |
Glued laminated timber, commonly referred to as glulam, is a type of structural engineered wood product constituted by layers of dimensional lumber bonded together with durable, moisture-resistant structural adhesives so that all of the grain runs parallel to the longitudinal axis. In North America, the material providing the laminations is termed laminating stock or lamstock.
History
The principles of glulam construction are believed to date back to the 1860s, in the assembly room of King Edward VI College, a school in Southampton, England | https://huggingface.co/datasets/fmars/wiki_stem |
Graphalloy is the trademark for a group of metal-impregnated graphite materials. The materials are commonly used for self-lubricating plain bearings or electrical contacts. They are proprietary materials owned by the Graphite Metallizing Corp | https://huggingface.co/datasets/fmars/wiki_stem |
High Strain Composite Structures (HSC Structures) are a class of composite material structures designed to perform in a high deformation setting. High strain composite structures transition from one shape to another upon the application of external forces. A single HSC Structure component is designed to transition between at least two, but often more, dramatically different shapes | https://huggingface.co/datasets/fmars/wiki_stem |
Homasote is a brand name associated with the product generically known as cellulose-based fiber wall board, which is similar in composition to papier-mâché, made from recycled paper that is compressed under high temperature and pressure. Homasote contains no adhesives. It is held together by the surface tension between the paper fibers, a process that is augmented by hydrogen bonding and the presence of a wax binder (2% volume) | https://huggingface.co/datasets/fmars/wiki_stem |
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