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List of ASTM International Standards
This is a list of ASTM International standards. Standard designations usually consist of a letter prefix and a sequentially assigned number. This may optionally be followed by a dash and the last two digits of the year in which the standard was adopted. Prefix letters correspond to the following subjects: This list may include either current or withdrawn standards. A withdrawn standard has been discontinued by its sponsoring committee. A standard may be withdrawn with or without replacement.
  • 3.5K
  • 01 Nov 2022
Topic Review
Physical Unclonable Function
A Physical Unclonable Function (PUF) is hardware that acts as a one-way function, whose each different instance provides unique outputs for the same distinct input. Although recent research has demonstrated the merits of PUFs as security primitives for resource-constrained computer systems, better implementations of them need to be identified by future research, in order for them to be commercially adopted. Nevertheless, PUFs have already found application in the implementation of a large number of cryptographic protocols and other security solutions. A number of well-known metrics have been proposed in the literature in order to assess the quality of individual PUF implementations as security mechanisms, in terms of the stability, uniqueness and randomness of their responses.
  • 3.5K
  • 24 Mar 2023
Topic Review
ATtiny Microcontroller Comparison Chart
ATtiny (also known as TinyAVR) are a subfamily of the popular 8-bit AVR microcontrollers, which typically has fewer features, fewer I/O pins, and less memory than other AVR series chips. The first members of this family were released in 1999 by Atmel (later acquired by Microchip Technology in 2016).
  • 3.5K
  • 03 Nov 2022
Topic Review
Surface Passivation
Passivation, in physical chemistry and engineering, refers to coating a material so it becomes "passive", that is, less readily affected or corroded by the environment. Passivation involves creation of an outer layer of shield material that is applied as a microcoating, created by chemical reaction with the base material, or allowed to build by spontaneous oxidation in the air. As a technique, passivation is the use of a light coat of a protective material, such as metal oxide, to create a shield against corrosion. Passivation of silicon is used during fabrication of microelectronic devices. In electrochemical treatment of water, passivation reduces the effectiveness of the treatment by increasing the circuit resistance, and active measures are typically used to overcome this effect, the most common being polarity reversal, which results in limited rejection of the fouling layer.[clarification needed] When exposed to air, many metals naturally form a hard, relatively inert surface layer, usually an oxide (termed the "native oxide layer") or a nitride, that serves as a passivation layer. In the case of silver, the dark tarnish is a passivation layer of silver sulfide formed from reaction with environmental hydrogen sulfide. (In contrast, metals such as iron oxidize readily to form a rough porous coating of rust that adheres loosely and sloughs off readily, allowing further oxidation.) The passivation layer of oxide markedly slows further oxidation and corrosion in room-temperature air for aluminium, beryllium, chromium, zinc, titanium, and silicon (a metalloid). The inert surface layer formed by reaction with air has a thickness of about 1.5 nm for silicon, 1–10 nm for beryllium, and 1 nm initially for titanium, growing to 25 nm after several years. Similarly, for aluminium, it grows to about 5 nm after several years. Surface passivation refers to a common semiconductor device fabrication process critical to modern electronics. It is the process by which a semiconductor surface such as silicon is rendered inert, and does not change semiconductor properties when it interacts with air or other materials. This is typically achieved by thermal oxidation, in which the material is heated and exposed to oxygen. In a silicon semiconductor, this process allows electricity to reliably penetrate to the conducting silicon below the surface, and to overcome the surface states that prevent electricity from reaching the semiconducting layer. Surface passivation by thermal oxidation is one of the key features of silicon technology, and is dominant in microelectronics. The surface passivation process was developed by Mohamed M. Atalla at Bell Labs in the late 1950s. It is commonly used to manufacture MOSFETs (metal-oxide-semiconductor field-effect transistors) and silicon integrated circuit chips (with the planar process), and is critical to the semiconductor industry. Surface passivation is also critical to solar cell and carbon quantum dot technologies.
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  • 22 Nov 2022
Topic Review
Flat Panel Display
Flat-panel displays are electronic viewing technologies used to enable people to see content (still images, moving images, text, or other visual material) in a range of entertainment, consumer electronics, personal computer, and mobile devices, and many types of medical, transportation and industrial equipment. They are far lighter and thinner than traditional cathode ray tube (CRT) television sets and video displays and are usually less than 10 centimetres (3.9 in) thick. Flat-panel displays can be divided into two display device categories: volatile and static. Volatile displays require that pixels be periodically electronically refreshed to retain their state (e.g., liquid-crystal displays (LCD)). A volatile display only shows an image when it has battery or AC mains power. Static flat-panel displays rely on materials whose color states are bistable (e.g., e-book reader tablets from Sony), and as such, flat-panel displays retain the text or images on the screen even when the power is off. As of 2016, flat-panel displays have almost completely replaced old CRT displays. In many 2010-era applications, specifically small portable devices such as laptops, mobile phones, smartphones, digital cameras, camcorders, point-and-shoot cameras, and pocket video cameras, any display disadvantages of flat-panels (as compared with CRTs) are made up for by portability advantages (thinness and lightweightness). Most 2010s-era flat-panel displays use LCD and/or LED technologies. Most LCD screens are back-lit as color filters are used to display colors. Flat-panel displays are thin and lightweight and provide better linearity and they are capable of higher resolution than typical consumer-grade TVs from earlier eras. The highest resolution for consumer-grade CRT TVs was 1080i; in contrast, many flat-panels can display 1080p or even 4K resolution. As of 2016, some devices that use flat-panels, such as tablet computers, smartphones and, less commonly, laptops, use touchscreens, a feature that enables users to select onscreen icons or trigger actions (e.g., playing a digital video) by touching the screen. Many touchscreen-enabled devices can display a virtual QWERTY or numeric keyboard on the screen, to enable the user to type words or numbers. A multifunctional monitor (MFM) is a flat-panel display that has additional video inputs (more than a typical LCD monitor) and is designed to be used with a variety of external video sources, such as VGA input, HDMI input from a VHS VCR or video game console and, in some cases, a USB input or card reader for viewing digital photos). In many instances, an MFM also includes a TV tuner, making it similar to a LCD TV that offers computer connectivity.
  • 3.5K
  • 25 Nov 2022
Topic Review
V-Models for the Development Procedures and Functional Safety
The design of modern industrial products is further improved through the hardware-in-the-loop (HIL) simulation. An HIL model can bypass serious damage to the real object, reduce debugging cost, and, finally, reduce the comprehensive effort during the testing.
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  • 29 Aug 2022
Topic Review
Czochralski Process
The Czochralski process is a method of crystal growth used to obtain single crystals of semiconductors (e.g. silicon, germanium and gallium arsenide), metals (e.g. palladium, platinum, silver, gold), salts and synthetic gemstones. The process is named after Polish scientist Jan Czochralski, who invented the method in 1915 while investigating the crystallization rates of metals. He made this discovery by accident: instead of dipping his pen into his inkwell, he dipped it in molten tin, and drew a tin filament, which later proved to be a single crystal. The most important application may be the growth of large cylindrical ingots, or boules, of single crystal silicon used in the electronics industry to make semiconductor devices like integrated circuits. Other semiconductors, such as gallium arsenide, can also be grown by this method, although lower defect densities in this case can be obtained using variants of the Bridgman-Stockbarger technique.
  • 3.5K
  • 24 Nov 2022
Topic Review
COTS-Based Architectural Framework
This research tackles issues such as the reliability and efficiency of real-time control systems based on commercial off-the-shelf (COTS) components. A strong emphasis is placed on finding novel efficient solutions based on standardized and commercially available off-the-shelf hardware/software components. In this direction, this research applies credible and feasible methodologies (e.g., model-based design, component-based design, formal verification, real-time scheduling, prototyping, and validation) in an innovative enhanced way. As an important outcome, a versatile integrative design approach and architectural framework (VIDAF) is proposed, which supports the development and implementation of reliable real-time control systems and applications using commercial off-the-shelf components. The feasibility and applicability of the proposed system’s architecture are evaluated and validated through a system application in embedded real-time control in manufacturing. The research outcomes are expected to have a positive impact on emerging areas such as the Industrial Internet of Things (IIoT).
  • 3.5K
  • 28 Oct 2020
Topic Review
Contact Lens Materials - A Materials Science Perspective
Contact lens materials are typically based on polymer- or silicone-hydrogel, with additional manufacturing technologies employed to produce the final lens. These processes are simply not enough to meet the increasing demands from CLs and the ever-increasing number of contact lens (CL) users. New materials and engineering offer increasing functionality or improved properties over previous generations.
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  • 27 Jan 2022
Topic Review
Virtual Power Plants (VPPs)
A virtual power plants (VPPs) is an alternative for the management of Distributed Energy Resources (DER) in the electricity system, which operates based on the concept of the “virtual cloud”. Its specific role is visibility and the technical and commercial integration of DERs in the power system. It is capable of grouping and managing the technical potential of different DERs (microgrids included), regardless of the voltage level at which they are interconnected with the network and without a geographical restriction between the elements. It is modeled as a single virtual element associated with the distribution network to guarantee a safe, efficient, cooperative and complementary operation between its elements, both in commercial and technical aspects. The VPP has the capacity to participate in the electricity market as a manager of controllable loads and as a provider of energy, power reserve and ancillary services.
  • 3.5K
  • 18 Feb 2022
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