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Measurement Standards Laboratory
Metrology is the scientific study of measurement. It establishes a common understanding of units, crucial in linking human activities. Modern metrology has its roots in the French Revolution's political motivation to standardise units in France when a length standard taken from a natural source was proposed. This led to the creation of the decimal-based metric system in 1795, establishing a set of standards for other types of measurements. Several other countries adopted the metric system between 1795 and 1875; to ensure conformity between the countries, the ''Bureau International des Poids et Mesures'' (BIPM) was established by the Metre Convention. This has evolved into the International System of Units (SI) as a result of a resolution at the 11th General Conference on Weights and Measures (CGPM) in 1960. Metrology is divided into three basic overlapping activities: * The definition of units of measurement * The realisation of these units of measurement in practice * Trac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standardisation
Standardization (American English) or standardisation (British English) is the process of implementing and developing technical standards based on the consensus of different parties that include firms, users, interest groups, standards organizations and governments. Standardization can help maximize compatibility, interoperability, safety, repeatability, efficiency, and quality. It can also facilitate a normalization of formerly custom processes. In social sciences, including economics, the idea of ''standardization'' is close to the solution for a coordination problem, a situation in which all parties can realize mutual gains, but only by making mutually consistent decisions. Divergent national standards impose costs on consumers and can be a form of non-tariff trade barrier. History Early examples Standard weights and measures were developed by the Indus Valley civilization.Iwata, Shigeo (2008), "Weights and Measures in the Indus Valley", ''Encyclopaedia of the History of S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
European Union
The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are Geography of the European Union, located primarily in Europe. The union has a total area of and an estimated population of over 449million as of 2024. The EU is often described as a ''sui generis'' political entity combining characteristics of both a federation and a confederation. Containing 5.5% of the world population in 2023, EU member states generated a nominal gross domestic product (GDP) of around €17.935 trillion in 2024, accounting for approximately one sixth of global economic output. Its cornerstone, the European Union Customs Union, Customs Union, paved the way to establishing European Single Market, an internal single market based on standardised European Union law, legal framework and legislation that applies in all member states in those matters, and only those matters, where the states ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WELMEC
WELMEC is a body set up to promote European cooperation in the field of legal metrology. WELMEC members are drawn from the national authorities responsible for legal metrology in European Union (EU) and European Free Trade Association (EFTA) member states. WELMEC state their mission as being "to develop and maintain mutual acceptance among its members and to maintain effective cooperation to achieve a harmonised and consistent approach to the societies needs for legal metrology and for the benefit of all stakeholders including consumers and businesses." WELMEC was established in 1990, at a meeting in Bern, Switzerland, and was originally the acronym for the "Western European Legal Metrology Cooperation". WELMEC has 30 members and 7 associate members. Today, although the name is still WELMEC, as the European Union extended its membership outside Western Europe, so did WELMEC, the organisation's membership encompassing EU member states, EFTA members and aspiring EU members: one o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OIML
The International Organization of Legal Metrology ( - OIML), is an intergovernmental organization, intergovernmental organisation that was created in 1955 to promote the global harmonisation of the legal metrology procedures that underpin and facilitate international trade. Such harmonisation ensures that certification of measuring devices in one country is compatible with certification in another, thereby facilitating trade in the measuring devices and in products that rely on the measuring devices. Such products include Weighing scale, weighing devices, Taximeter, taxi meters, speedometers, agricultural measuring devices such as Moisture meter, cereal moisture meters, health related devices such as Exhaust gas, exhaust measurements and Alcohol by volume, alcohol content of drinks. Since its establishment, the OIML has developed a number of guidelines to assist its Members, particularly developing nations, to draw up appropriate legislation concerning metrology across all facets o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Measuring Instrument
Instrumentation is a collective term for measuring instruments, used for indicating, measuring, and recording physical quantities. It is also a field of study about the art and science about making measurement instruments, involving the related areas of metrology, automation, and control theory. The term has its origins in the art and science of scientific instrument-making. Instrumentation can refer to devices as simple as direct-reading thermometers, or as complex as multi- sensor components of industrial control systems. Instruments can be found in laboratories, refineries, factories and vehicles, as well as in everyday household use (e.g., smoke detectors and thermostats). Measurement parameters Instrumentation is used to measure many parameters (physical values), including: *Pressure, either differential or static * Flow *Temperature * Levels of liquids, etc. *Moisture or humidity *Density *Viscosity * ionising radiation * Frequency * Current *Voltage * Induct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avogadro Project
The scientific community examined several approaches to redefining the kilogram before deciding on a revision of the SI in November 2018. Each approach had advantages and disadvantages. Prior to the redefinition, the kilogram and several other SI units based on the kilogram were defined by an artificial metal object called the international prototype of the kilogram (IPK). There was broad agreement that the older definition of the kilogram should be replaced. The International Committee for Weights and Measures (CIPM) approved a redefinition of the SI base units in November 2018 that defines the kilogram by defining the Planck constant to be exactly . This approach effectively defines the kilogram in terms of the second and the metre, and took effect on 20 May 2019. In 1960, the metre, previously similarly having been defined with reference to a single platinum-iridium bar with two marks on it, was redefined in terms of an invariant physical constant (the wavelength of a pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kibble Balance
A Kibble balance (also formerly known as a watt balance) is an electromechanical measuring instrument that measures the weight of a test object very precisely by the electric current and voltage needed to produce a compensating force. It is a Metrology, metrological instrument that can realize the definition of the kilogram unit of mass based on Physical constant, fundamental constants. It was originally known as a watt balance because the weight of the test mass is proportional to the product of current and voltage, which is measured in watts. In June 2016, two months after the death of its inventor, Bryan Kibble, metrologists of the Consultative Committee for Units of the International Committee for Weights and Measures agreed to rename the device in his honor. Prior to 2019, the definition of the kilogram was based on a physical object known as the International Prototype of the Kilogram (IPK). Alternative approaches to redefining the kilogram, After considering alternative ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Institute Of Physics
The Institute of Physics (IOP) is a UK-based not-for-profit learned society and professional body that works to advance physics education, physics research, research and applied physics, application. It was founded in 1874 and has a worldwide membership of over 20,000. The IOP is the Physical Society for the UK and Ireland and supports physics in education, research and industry. In addition to this, the IOP provides services to its members including careers advice and professional development and grants the Professional qualifications in the United Kingdom, professional qualification of Chartered Physicist (CPhys), as well as Chartered Engineer (UK), Chartered Engineer (CEng) as a nominated body of the Engineering Council; it also holds its own separate Royal Charter. The IOP's publishing company, IOP Publishing, publishes 85 academic titles. History The Institute of Physics was formed in 1960 from the merger of the Physical Society of London, Physical Society, founded as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planck Constant
The Planck constant, or Planck's constant, denoted by h, is a fundamental physical constant of foundational importance in quantum mechanics: a photon's energy is equal to its frequency multiplied by the Planck constant, and the wavelength of a matter wave equals the Planck constant divided by the associated particle momentum. The constant was postulated by Max Planck in 1900 as a proportionality constant needed to explain experimental black-body radiation. Planck later referred to the constant as the "quantum of Action (physics), action". In 1905, Albert Einstein associated the "quantum" or minimal element of the energy to the electromagnetic wave itself. Max Planck received the 1918 Nobel Prize in Physics "in recognition of the services he rendered to the advancement of Physics by his discovery of energy quanta". In metrology, the Planck constant is used, together with other constants, to define the kilogram, the SI unit of mass. The SI units are defined in such a way that, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physical Constants
A physical constant, sometimes fundamental physical constant or universal constant, is a physical quantity that cannot be explained by a theory and therefore must be measured experimentally. It is distinct from a mathematical constant, which has a fixed numerical value, but does not directly involve any physical measurement. There are many physical constants in science, some of the most widely recognized being the speed of light in vacuum ''c'', the gravitational constant ''G'', the Planck constant ''h'', the electric constant ''ε''0, and the elementary charge ''e''. Physical constants can take many dimensional analysis, dimensional forms: the speed of light signifies a maximum speed for any object and its Dimensional analysis, dimension is length divided by time; while the proton-to-electron mass ratio is dimensionless. The term "fundamental physical constant" is sometimes used to refer to universal-but-dimensioned physical constants such as those mentioned above. Increasingly, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ionizing Radiation
Ionizing (ionising) radiation, including Radioactive decay, nuclear radiation, consists of subatomic particles or electromagnetic waves that have enough energy per individual photon or particle to ionization, ionize atoms or molecules by detaching electrons from them. Some particles can travel up to 99% of the speed of light, and the electromagnetic waves are on the high-energy portion of the electromagnetic spectrum. Gamma rays, X-rays, and the higher energy vacuum ultraviolet, ultraviolet part of the electromagnetic spectrum are ionizing radiation; whereas the lower energy ultraviolet, visible light, infrared, microwaves, and radio waves are non-ionizing radiation. Nearly all types of laser light are non-ionizing radiation. The boundary between ionizing and non-ionizing radiation in the ultraviolet area cannot be sharply defined, as different molecules and atoms ionize at Ionization energies of the elements (data page), different energies. The energy of ionizing radiation starts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
