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Acoustic Emission
Acoustic emission (AE) is the phenomenon of radiation of acoustic (elastic) waves in solids that occurs when a material undergoes irreversible changes in its internal structure, for example as a result of crack formation or plastic deformation due to aging, temperature gradients, or external mechanical forces. In particular, AE occurs during the processes of ''mechanical loading'' of materials and structures accompanied by structural changes that generate local sources of elastic waves. This results in small surface displacements of a material produced by elastic or stress waves generated when the accumulated elastic energy in a material or on its surface is released rapidly. The mechanism of emission of the primary elastic pulse AE (act or event AE) may have a different physical nature. The figure shows the mechanism of the AE act (event) during the nucleation of a microcrack due to the breakthrough of the dislocations pile-up (dislocation is a linear defect in the crystal lattice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AE Event
AE, Ae, ae, aE, Æ or æ may refer to: Arts and entertainment * A.E. (video game), ''A.E.'' (video game), 1982 * Ae (film), ''Ae'' (film), a 2022 Sri Lankan film * Autechre, an electronic music group * ''L'Année épigraphique'', a French publication on epigraphy * ''Encyclopedia Dramatica'', often abbreviated æ * Artix Entertainment, a video game developer and publisher Language Characters * Æ or æ, a ligature or letter **list of English words that may be spelled with a ligature, including "AE" being rendered as "Æ" * Ä or ä, a letter sometimes represented as "ae" * Ae (Cyrillic), a Cyrillic-script letter * Ae (digraph), a Latin-script digraph Languages and dialects * American English, varieties of the English language native to the USA; abbr. AE, usually used in contrast to BE (British English). * Avestan, a language, ISO 639-1 language code ae People * A. E. or Æ, a penname of George William Russell (1867–1935), Irish writer * A. E. Holt White (1851-1933), English ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nondestructive Testing
Nondestructive testing (NDT) is any of a wide group of analysis techniques used in science and technology industry to evaluate the properties of a material, component or system without causing damage. The terms nondestructive examination (NDE), nondestructive inspection (NDI), and nondestructive evaluation (NDE) are also commonly used to describe this technology. Because NDT does not permanently alter the article being inspected, it is a highly valuable technique that can save both money and time in product evaluation, troubleshooting, and research. The six most frequently used NDT methods are eddy-current testing, eddy-current, magnetic-particle inspection, magnetic-particle, liquid penetrant testing, liquid penetrant, radiographic testing, radiographic, ultrasonic testing, ultrasonic, and Visual inspection, visual testing. NDT is commonly used in forensic engineering, mechanical engineering, petroleum engineering, electrical engineering, civil engineering, systems engineering, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acoustics
Acoustics is a branch of physics that deals with the study of mechanical waves in gases, liquids, and solids including topics such as vibration, sound, ultrasound and infrasound. A scientist who works in the field of acoustics is an acoustician while someone working in the field of acoustics technology may be called an Acoustical engineering, acoustical engineer. The application of acoustics is present in almost all aspects of modern society with the most obvious being the audio and noise control industries. Hearing (sense), Hearing is one of the most crucial means of survival in the animal world and speech is one of the most distinctive characteristics of human development and culture. Accordingly, the science of acoustics spreads across many facets of human society—music, medicine, architecture, industrial production, warfare and more. Likewise, animal species such as songbirds and frogs use sound and hearing as a key element of mating rituals or for marking territories. Art, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Institute Of Non-Destructive Testing
The British Institute of Non-Destructive Testing or BINDT is a professional body for engineers and other technical professionals involved in non-destructive testing and condition monitoring in the United Kingdom. The institute was founded in 1976, by amalgamation of the ''Society of Non-Destructive Examination'' (SONDE) and the ''NDT Society of Great Britain'' (NDTS), which were both founded in 1954. BINDT is a licensed member institution of the Engineering Council and a full member of the European Federation of NDT (EFNDT) and the International Committee for NDT (ICNDT). Their headquarters is located in Northampton, UK. Certification BINDT maintains PCNPersonnel Certification in Non-Destructive Testing. PCN is a personnel certification scheme in NDT methods, welding inspection and condition monitoring, which is accredited by UKAS according to ISO 17024. PCN certification schemes for the major NDT methods conform to BS EN ISO 9712 (2012). PCN condition monitoring certificatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CNC Machine Tool Monitoring By AE Sensors
A machine tool monitoring system is a flow of information and system processing in which the information selection, obtaining data, processing of information and decision making on the refined information are integrated. The aim of tool condition monitoring is to detect early the disturbances in the machining process and wear of machine tool components. The condition of tool has been researched extensively in the past and have focused on detection of tool wear, tool breakage and the estimation of remaining tool life. It is very important for on-line identification of tool condition in machining process for enhanced productivity, better quality of parts and lower costs for unmanned, automated manufacturing systems. Techniques of machine tool monitoring Machine tool monitoring can be done with or without additional sensors. Using additional sensors, monitoring can be done by measuring: * the cutting force (with a multi-channel table dynamometer or rotating dynamometer) * vibration ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seismometer
A seismometer is an instrument that responds to ground displacement and shaking such as caused by quakes, volcanic eruptions, and explosions. They are usually combined with a timing device and a recording device to form a seismograph. The output of such a device—formerly recorded on paper (see picture) or film, now recorded and processed digitally—is a ''seismogram''. Such data is used to locate and characterize earthquakes, and to study the internal structure of Earth. Basic principles A simple seismometer, sensitive to up-down motions of the Earth, is like a weight hanging from a spring, both suspended from a frame that moves along with any motion detected. The relative motion between the weight (called the mass) and the frame provides a measurement of the vertical ground motion. A rotating drum is attached to the frame and a pen is attached to the weight, thus recording any ground motion in a seismogram. Any movement from the ground moves the frame. The mass tends ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accelerometer
An accelerometer is a device that measures the proper acceleration of an object. Proper acceleration is the acceleration (the rate of change (mathematics), rate of change of velocity) of the object relative to an observer who is in free fall (that is, relative to an inertial frame of reference). Proper acceleration is different from coordinate acceleration, which is acceleration with respect to a given coordinate system, which may or may not be accelerating. For example, an accelerometer at rest on the surface of the Earth will measure an Gravitational acceleration, acceleration due to Earth's gravity straight upwards of about Standard gravity, ''g'' ≈ 9.81 m/s2. By contrast, an accelerometer that is in free fall will measure zero acceleration. Accelerometers have many uses in industry, consumer products, and science. Highly sensitive accelerometers are used in inertial navigation systems for aircraft and missiles. In unmanned aerial vehicles, accelerometers help to stabili ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Process Monitoring
Industrial process control (IPC) or simply process control is a system used in modern manufacturing which uses the principles of control theory and physical industrial control systems to monitor, control and optimize continuous industrial production processes using control algorithms. This ensures that the industrial machines run smoothly and safely in factories and efficiently use energy to transform raw materials into high-quality finished products with reliable consistency while reducing energy waste and economic costs, something which could not be achieved purely by human manual control. In IPC, control theory provides the theoretical framework to understand system dynamics, predict outcomes and design control strategies to ensure predetermined objectives, utilizing concepts like feedback loops, stability analysis and controller design. On the other hand, the physical apparatus of IPC, based on automation technologies, consists of several components. Firstly, a network of s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gas Evolution Reaction
A gas evolution reaction is a chemical reaction in which one of the end products is a gas such as oxygen or carbon dioxide. Gas evolution reactions may be carried out in a fume chamber when the gases produced are poisonous when inhaled or explosive. Examples * A replacement reaction concerning zinc metal and dilute sulfuric acid. : Zn + H_2SO_4 (dil) -> ZnSO_4 + H_2 ^ : In this example, diatomic hydrogen gas is released. Dilute hydrochloric acid can be used in place of dilute sulfuric acid. * A replacement reaction where gaseous hydrogen chloride and fluorine gas react to release diatomic chlorine gas (because fluorine is more electronegative): : 2HCl + F_2 -> 2HF + Cl_2 ^ See also * Gasogene * Kipps apparatus * Gas generator * Thermal decomposition Thermal decomposition, or thermolysis, is a chemical decomposition of a substance caused by heat. The decomposition temperature of a substance is the temperature at which the substance chemically decomposes. The reaction is usua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phase Transition
In physics, chemistry, and other related fields like biology, a phase transition (or phase change) is the physical process of transition between one state of a medium and another. Commonly the term is used to refer to changes among the basic State of matter, states of matter: solid, liquid, and gas, and in rare cases, plasma (physics), plasma. A phase of a thermodynamic system and the states of matter have uniform physical property, physical properties. During a phase transition of a given medium, certain properties of the medium change as a result of the change of external conditions, such as temperature or pressure. This can be a discontinuous change; for example, a liquid may become gas upon heating to its boiling point, resulting in an abrupt change in volume. The identification of the external conditions at which a transformation occurs defines the phase transition point. Types of phase transition States of matter Phase transitions commonly refer to when a substance tran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrode
An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit (e.g. a semiconductor, an electrolyte, a vacuum or a gas). In electrochemical cells, electrodes are essential parts that can consist of a variety of materials (chemicals) depending on the type of cell. An electrode may be called either a cathode or anode according to the direction of the electric current, unrelated to the potential difference between electrodes. Michael Faraday coined the term "" in 1833; the word recalls the Greek ἤλεκτρον (, "amber") and ὁδός (, "path, way"). The electrophore, invented by Johan Wilcke in 1762, was an early version of an electrode used to study static electricity. Anode and cathode in electrochemical cells Electrodes are an essential part of any battery. The first electrochemical battery was devised by Alessandro Volta and was aptly named the Voltaic cell. This battery consisted of a stack of copper and zinc electrodes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tsar Bell
The Tsar Bell (; ), also known as the Tsarsky Kolokol, Tsar Kolokol III, or Royal Bell, is a , bell on display on the grounds of the Moscow Kremlin. The bell was commissioned by Empress Anna Ivanovna, niece of Peter the Great. It has never been in working order, suspended, nor rung. The present bell is sometimes referred to as ''Kolokol III'' (Bell III), because it is the third generation. General description The Tsar Bell is located between the Ivan the Great Bell Tower and the Kremlin Wall. Made of bell bronze, the bell cracked during a fire after being completed and has never been rung. The bell is the largest bell in the world, weighing , with a height of and diameter of , and thickness of up to . The broken piece weighs . At 116 metric tons, the Bell of Good Luck in Foquan Temple, Pingdingshan, Henan, China is the heaviest ''functioning'' bell in the world. The bell is decorated with relief images of baroque angels, plants, oval medallions with saints, and near ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
