REFERENCE

(from fr. etalon - measure, measure) - English standard; German Etalon. 1. A measure, a sample for comparison with something. 2. Regulatory "configuration" future activities, any target system can be used as the basis for searching for practical solutions and constructing reality (or its elements). 3. Sample measure or measuring device, used to reproduce, store and transmit units of measurement with the highest (achievable in the given state of science and technology) accuracy.

Antinazi. Encyclopedia of Sociology, 2009

Synonyms:

See what "ETALON" is in other dictionaries:

- (French etalon sample, measure) will measure. a device designed and approved for reproducing and (or) storing and transmitting a measurement scale or unit size to measuring instruments. E. are designed to ensure the uniformity of measurements in... ... Physical encyclopedia

Reference- Standard. The international standard unit of mass of the kilogram is a platinum-iridium weight in the shape of a cylinder with a diameter and height of 39 mm. STANDARD (French etalon), 1) a measure or measuring device used to reproduce, store and transmit a unit... ... Illustrated Encyclopedic Dictionary

reference- a, m. étalon m. 1. An exemplary measure or an exemplary measuring device used for reproducing, storing and transmitting a unit of measurement of something. BAS 1. Jacobi made and sent to many scientists a resistance standard, copper wire, special... ... Historical Dictionary Gallicisms of the Russian language

Sample, standard, standard sample, original; measure, yardstick, sample, example, ideal Dictionary of Russian synonyms. standard, see sample 1 Dictionary of synonyms of the Russian language. Practical guide. M.: Russian language. Z. E. Alexandrova ... Synonym dictionary

- (French etalon) ..1) a measure or measuring device used to reproduce, store and transmit units of any quantity. The standard approved as the initial one for the country is called the State Standard2)] (In a figurative sense) ... ... Big Encyclopedic Dictionary

- (French etalon), 1) a measure or measuring device used to reproduce, store and transmit a unit of any quantity. A standard approved as a reference for a country and which is a copy of an international standard is called... ... Modern encyclopedia

STANDARD, standard, husband. (French étalon). A sample measure used to check measuring devices in circulation (technical, physical). Meter standard. || trans. A template, a ready-made measure for something (book). Dictionary Ushakova. D.N.... ... Ushakov's Explanatory Dictionary

STANDARD, a, m. Ozhegov's Explanatory Dictionary. S.I. Ozhegov, N.Yu. Shvedova. 1949 1992 … Ozhegov's Explanatory Dictionary

Standards are called samples of measures containing the possibly accurately defined number of units of that measure, the example of which E should serve. The measurement of most quantities accepted in science and technology can, as is known, be reduced to the measurement of lengths, masses and ... ... Encyclopedia of Brockhaus and Efron

Exemplary measure, sample for comparison. Raizberg B.A., Lozovsky L.Sh., Starodubtseva E.B.. Modern economic dictionary. 2nd ed., rev. M.: INFRA M. 479 p.. 1999 ... Economic dictionary

Books

• Standard of Evil, Alexey Fomichev. Behind the neutral sign of the Scientific Experimental Committee hides a new Russian intelligence service, designed to ensure control over unauthorized transitions in time and between worlds. But when...

In Russia and many other countries of the world, the uniformity of measurements is ensured by the functioning centralized systems reproduction of units of quantities and transmission of their sizes, which are hierarchical chains of standards of varying accuracy.

Reference— SI (or SI complex), intended for reproducing and (or) storing a unit and transferring its size to other SI.

By place in this hierarchical chain standards are divided into primary, secondary and working.

Primary standard called a standard that reproduces a unit and transmits its size to secondary standards. Primary standard performs the task of reproducing a unit of a quantity for its use in all measurements of a given quantity. It is obvious that the accuracy levels of the most critical metrological and operational measurements are determined by the accuracies of the primary standards. Therefore, when creating primary standards, they always strive to ensure the highest accuracy that can be achieved at this stage of development of science and technology. After the unit is reproduced, its size is brought up to each standard along the hierarchical chain of standards.

Figure 1 illustrates this process. From the figure it is clear that the transfer of the size of a unit occurs in two ways: not only from more accurate standards to less accurate ones, but also by expanding the ranges of values ​​and measurement conditions. Moreover, since the result of each measurement is burdened with some kind of uncertainty, in the system for transmitting the size of a unit, the uncertainty of this unit continuously increases. Primary standard transfers the unit size to secondary standards, which operate over a wider measurement range but are less accurate. Secondary standards transmit the size of the unit to working standards (standard SI (hereinafter referred to as OSI)), and those to less accurate working standards (OSI).

Rice. 1. Scheme for reproducing a unit and transferring its size to standards

The number of transmission stages is determined by the requirements for the accuracy of working SIs and therefore cannot be very large. In many types of measurements, an increase in the range of values ​​and measurement conditions (frequency, temperature, etc.) has led to the impossibility of ensuring the transfer of the unit size with the required accuracy from the current primary standard to all SIs of this type. In these cases, several primary standards of one unit are created, differing in measurement ranges or measurement conditions.

For example, in Russia, the pressure unit is reproduced by seven different primary standards, six of which are stored at VNIIM. DI. Mendeleev and one at VNIIFTRI.

Another example: one specific heat capacity reproduce four primary standards stored at VNIIM. DI. Mendeleev, UNIIM, NPO Dalstandart and VNIIFTRI. Such a group of primary standards is actually a reference set designed to reproduce a unit over the entire measurement range. Moreover, in Russia one of these standards is called the “primary standard”. The remaining standards in this set are called special primary standards (short form - special standards).

In the examples given primary standards are called state standards stored at VNIIM named after. DI. Mendeleev, units of pressure in the range of 0.05-10 MPa and specific heat capacity in the temperature range of 273.15-700 K. To ensure uniformity of measurements, the unit sizes reproduced by these standards are consistent in the boundary ranges of values.

All other standards do not participate in the reproduction of units. They store unit sizes obtained from more accurate standards and/or transfer them to less accurate standards and working SIs.

Secondary standards receive unit sizes from primary standards and transmit it to working standards.

Working standards are intended for verification and calibration of working measuring instruments. If necessary, they are divided into categories: 1st, 2nd, 3rd, etc. In this case, working standards of the 1st category also transfer the unit size to working standards of the 2nd category, working standards of the 2nd category - working standards of the 3rd category, etc.

The above names correspond to the international classification of standards, recognized throughout the world, including in Russia. At the same time, the classification adopted in Russia is somewhat different from the international one. Working standards according to the international classification until the last decade in our country were called exemplary SI (OSI). These terms are actually synonymous: at one time they translated this into Russian French word"reference". But in Russia there have always been significant differences in the status of primary and secondary standards (the totality of which is called the country’s standard base) and OSI and the resulting differences in funding and the metrological service system.

After the transition to the international classification, the status of OSI (including serially produced OMI of lower categories) seemed to be equal to the status of primary and secondary standards, with all the ensuing negative consequences for the latter. In order to restore the previous position and at the same time not contradict the international classification of standards, it has now been decided to apply both terms (both working standard and OSI) in Russia as equal.

The standards include:

1. means of reproducing the unit (primary measuring transducers, measuring installations);
2. means of storing unit sizes (measures);
3. means of transmitting unit sizes (comparators, comparison standards);
4. means of storing and transmitting unit dimensions (measuring instruments);
5. other SI and technical means(means for monitoring measurement conditions, computing tools, power systems, measuring accessories, etc.).

Structurally, standards and OSI can be designed in the form measuring installations, called in this case verification installations.

Basic metrological requirements for standards and OSI must ensure high accuracy of measurement results when reproducing the unit, storing and (or) transmitting its size.

The most important requirement is high stability to ensure that the unit size remains unchanged. This is precisely what explains the transition at the turn of the 20th and 21st centuries to the reproduction of basic and many derivative units through the implementation of highly stable quantum physical effects. Also necessary are high sensitivity and small random error of the standard, as well as its low sensitivity to changes in measurement conditions.

A means of increasing the accuracy of measurements on a standard and reducing the operator’s personal errors is the automation of measuring and computing operations. At the same time, the size of the range of measurement conditions is not an essential characteristic, since in order to increase the accuracy of reference measurements, standards are usually used under fixed (most often normal) measurement conditions.

Based on the number of measuring instruments of the same name included in the standard, a distinction is made between single standards, standard sets and group standards.

Single standard consists of one SI.

Another type of standard is reference set- is a combination of single standards with different nominal values, which allows you to expand the range of reproducible, stored as the standard deviation of the arithmetic mean value.

A centralized system for ensuring the uniformity of measurements can be organized in metrological services at various levels: at a separate enterprise, in a department, in the country as a whole.

In this case, the hierarchical chain of transmission of the unit size to all SIs of this type of measurement used in a given metrological service will be headed by one, the most accurate standard. This standard is called the original standard (enterprise, department, country). In this way, traceability of all measurements carried out in an enterprise or department is ensured to their original standards, and through them to the original standards of the country.

Country reference standards in international metrological practice they are called national standards; in our country they are called state standards.

To ensure the uniformity of measurements, it is necessary to have identical units in which all measuring instruments of the same physical quantity are calibrated. This is achieved by accurately reproducing and storing established units of physical quantities and transferring their sizes to the measuring instruments used.

Reproduction, storage and transmission of unit sizes are carried out using standards.

Standards are divided into primary, secondary and working.

Primary standards reproduce units of physical quantities with highest accuracy, achievable in a given measurement area. Primary standards of basic units reproduce the unit in accordance with its definition. A type of primary standards are special standards, designed to reproduce units in established special conditions(ultrahigh frequencies, low and high energies, pressure, temperature, etc.). Primary and special standards, officially approved as reference standards for a country, are called state , each of them is approved by a state standard.

Secondary standards are created to organize verification work and ensure the safety and least wear of the State Standard. The value of secondary standards is established by primary standards. According to their metrological purpose, secondary standards are divided into: 1) copy standards; 2) standards of comparison; 3) witness standards; 4) working standards.

Reference copy is a secondary standard designed to store a unit and transfer its size to working standards. It may not always be a physical copy of the state standard.

Standard of comparison- a secondary standard used for comparison of standards that, for one reason or another, cannot be directly compared with each other. An example of a comparison standard is the group of normal elements used to compare the State Volt Standard of the USSR with the Volt Standard of the International Bureau of Weights and Measures.

Standard witness- a secondary standard used to check the safety of the state standard and to replace it in case of damage or loss. The witness standard is used only when the state standard is not reproduced.

Working standards- standards of the 1st, 2nd, 3rd and 4th categories, used to store a unit and transfer its size to working measuring instruments.

Fig.2.8. Classification of standards by subordination.

In addition to national standards, there are international standards, belonging to a group of countries and intended to maintain the uniformity of measurements on an international scale through periodic comparison of national standards with the international one and with each other. International standards are stored and maintained by the International Bureau of Weights and Measures (BIPM).

State standards of basic units of the SI system:

1. E mass unit coupon — The kilogram consists of a national prototype of the kilogram (a platinum-iridium alloy weight) and a reference scale designed to convey the size of a unit of mass to secondary standards. The standard deviation of the relative error in reproducing a unit of mass by the standard is 7·10 -9.

2. E length units coupon - a set of means that reproduce meter in the form 1 650 763,73 wavelengths of radiation in vacuum corresponding to the transition between certain levels of the atom krypton-86. The standard ensures reproduction of the meter with a relative standard deviation of the measurement result not exceeding 5·10 -9.

Meter was among the first units for which standards were introduced. Initially, during the introduction of the metric system of measures, one ten-millionth of a quarter of the length of the Paris meridian was adopted as the first standard of the meter. In 1799, based on its measurements, a standard meter was made in the form of a platinum gauge (Archive meter), which was a ruler about 25 mm wide, about 4 mm thick, with a distance between the ends of 1 m.

Platinum-iridium meter standard from 1889 to 1960

3. E time unit coupon — a set of tools that reproduce the second in the form 9 192 631 770 periods of oscillation electromagnetic radiation, corresponding to the transition between two hyperfine levels of the ground state of the atom cesium-133. This standard is also the standard for the unit of frequency - the hertz. It ensures the reproduction of units with a relative standard deviation of the measurement result not exceeding 1·10 -13, with a non-excluded relative systematic error not exceeding 1·10 -12.

Unit of time - second was first determined through the period of rotation of the Earth around its axis or the Sun. Until recently, a second was equal to 1/86400 of the solar average day. The average solar day was taken to be the time interval between two successive culminations of the “average” Sun. To define a unit of time. The average solar day is determined with an error of up to 10 -7 s.

4. E coupon unit of direct electric current - ampere is a complex of means that includes current scales. In current balances, which are equal-armed lever scales, on one side the rocker arm is acted upon by the interaction force of two solenoids, streamlined DC, and on the other side - a weight of known mass. When the scales are in equilibrium, the current strength is determined through the mass of the weight, acceleration free fall at the location of the scales and the constant of the electrodynamic system (two solenoids), depending on the shape and size of the solenoids, the diameter of the solenoid wire cross-section, the value of the relative magnetic permeability of the medium, etc.). Thus, the ampere is reproduced through the base units − meter, kilogram and second. The standard reproduces the ampere size with a relative standard deviation of the measurement result not exceeding 4·10 -6, with a relative systematic error not exceeding 8·10 -6.

5. Temperature unit standard The kelvin was defined by the XIII General Conference on Weights and Measures as a unit of thermodynamic temperature equal to 1/273.16 of the thermodynamic temperature of the triple point of water.

The triple point of water is the point of equilibrium of water in solid, liquid and gaseous phases.

The VII General Conference on Weights and Measures in 1927 adopted, and the IX General Conference in 1948 approved, the International Practical Temperature Scale, reproducible by certain constant reference points. Reference points are reproduced, realizing the state of equilibrium between phases pure substances. The accuracy of reproducing Kelvin and degrees Celsius varies in different temperature ranges. The highest reproduction accuracy is achieved at the triple point of water 273.16 K ±0.0002 K (or +0.01 ±0.0002 °C). As reference devices, a platinum resistance thermometer is used in the temperature range of 13.81 K and 630.74 ° C; platinum-rhodium-platinum thermocouple in the range between 630.74 and 1064,43 °C

The standard uses ampoules of reference points of the International temperature scale 1990 (MTSh-90):

• triple point (- 38.8344 °C);
• triple point of water (0.01 °C);
• melting point of gallium (29.7646 °C);
• solidification points: indium (156.5985 °C), tin (231.928 °C), zinc (419.527 °C), aluminum (660.323 °C), silver (961.78 °C)

6. Standard unit of luminous intensity - candela is the luminous intensity emitted from an area of ​​1/600000 m 2 cross-section of the full emitter, in a direction perpendicular to this cross-section at the emitter temperature equal to the solidification temperature of platinum at a pressure of 101325 Pa.

Candela is most accurately reproduced using a reference device - a full emitter. A complete emitter, sometimes called a blackbody (Fig. 2.9), is a small tube of thorium oxide with an internal diameter of about 2.5 mm, immersed in pure platinum. The platinum, in turn, is in a vessel pressed from fused thorium oxide powder, surrounded by thorium oxide powder. All this is placed in an outer fused quartz vessel.

The outer vessel is surrounded by a small number of turns of water-cooled copper tubing. A high frequency current (about 250 kHz) is passed through the tube, which heats the platinum until it melts. Along with the platinum, the thorium tube also heats up. Light is emitted from the cavity of the tube through a hole in its upper part. The brightness of the full emitter at the solidification temperature of platinum is compared using a photometer with the brightness of special incandescent lamps used as secondary standards.

The reproduction of the candela is assigned an error of ±0.5% based on the results of international comparisons.

Fig.2.9. Full emitter:

1 - high-frequency generator, 2 - full emitter, 3 - total internal reflection prism, 4 - photometer, 5 - standard incandescent lamp.

French etalon - sample, standard, ideal or installed type something) - 1) the same as the standard; 2) special shape ideal, i.e., a model that should be imitated. If the standard sets the lower limit of certain characteristics of an object, then E. is the upper limit. The subordination of life and activity (primarily production and technical) to a certain set of elements was especially characteristic of early traditionalist cultures. In the absence of a scientific institute and limited experience, the optimal type of product and the best way its production was determined by trial and error. Since literal repetition was impossible, some products turned out to be the most successful and became E. They tried to reproduce them, but, as a rule, they achieved only a more or less successful approximation.

Ancient philosophy derived the need to subordinate activity to one or another element from the categories of harmony and measure. Measure as the best, standard proportion was considered an integral sign of harmony. Accordingly, in any type of activity a person had to strive to follow E. In this case, the results turned out to be the best and were organically included in the universal harmony of the Cosmos. During this period, the term “canon” (i.e., rule, prescription), synonymous with E., was more often used. In art, canon meant a set of rules that had to be followed in the process of creation work of art. The rules contained optimal ratios of parts of depicted or created objects. In logic, the canon included the rules for knowing the truth. Subsequently, in religion, a canon is a set of sacred books containing unconditional truth.

The cultural-creative function of E. was most significant for medieval Western European culture. The craftsman strove to reproduce the E. product generally accepted for the workshop of which he was a member. A student became a master if he managed to produce a masterpiece - a product approaching E. Generally accepted E. determined a technology that was standard in its main features, contributed to the formation of figurative subject ideas that explained it, and set the structure of an association of artisans, within the framework of which E. was reproduced, i.e. . a workshop that was both a production and social unit. The activities of all social strata followed a similar pattern. Thus, for chivalry, the material form of E. served as an object of imitation - one of the heroes of antiquity, legendary knights of the past, or famous contemporaries; technological form - a set of generally accepted rules of behavior that are subject to strict observance; ideal - a set of qualities befitting a knight. An analogue of a craft workshop was a knightly order; the production of a masterpiece corresponded to a standard feat, giving the squire the right to the status of a knight. IN cognitive activity the general tendency to reproduce E. determined the predominance of such a form of cognition as commenting on the standard (canonical) text. Since such a text was recognized as the highest form of knowledge containing the complete truth, direct appeal to the object of knowledge was not considered necessary. The role of a masterpiece-feat in the scientific community was played by the public defense of a dissertation - a scientific treatise in which standard texts were commented on according to certain standard rules.

In modern times, exact sciences and technology have become the main areas of economic activity. E. refers to measuring instruments or their complexes that ensure the reproduction and storage of legalized units of physical quantities, as well as the transfer of their size by other measuring instruments. Without E. it is impossible to achieve comparability of the results of measurements performed using different instruments in different places and at different times. These include the meter, kilogram, second, etc. The development of the meter system was stimulated by a general cultural value orientation towards precision, set by machine production, and the general spread of standardization.

In modern spiritual culture, cultural phenomena of the past that are considered the most significant, for example, the art of antiquity and the Renaissance, Russian classic literature, German classical philosophy, etc. They do not strive to imitate them literally, but since progress is not clearly expressed in the spiritual sphere, they a) set the “height” of creativity, b) are sources of creative experience and comprehension. The presence of E. ensures the continuity of spiritual culture. Personified forms of E., despite the weakening of the tendency to imitation, characteristic of the pre-industrial era, are preserved. As a rule, for the people of England there are not “great” or outstanding personalities known for their services to society, but those whose imitation is possible for ordinary person. Literary characters or cinematic heroes can act as E. The preference given to one or another person, his recognition as E. largely characterizes the corresponding historical period and social group.

Metrology. Basic concepts.

What is a standard?

A standard (measurement standard) may be a physical measure, a measuring instrument, a reference standard, or a measurement system designed to define, implement, store, or reproduce a unit or one or more values ​​of a quantity to serve as a standard. For example, a unit of mass is given physical form in the form of a cylindrical piece of metal weighing 1 kg; and graduated blocks represent specific length values.

The hierarchy of standards starts with the international standard as the top and goes down to the working standard. The definition of these terms is given in the International Dictionary of Basic and general terms in metrology, is given below:

The international standard is:

a standard recognized by international agreement to serve internationally as a basis for assigning values ​​to other standards of measurement for the quantity under consideration.

The custodian of international standards is the International Bureau of Weights and Measures (BIPM) in Sèvres, near Paris. The oldest standard of measurement in use is the kilogram standard.

The national standard is:

a standard recognized by national law to serve in a given country as a basis for assigning values ​​to other standards of measurement of the quantity under consideration.

Typically, the custodian of national standards is a national laboratory, called a national metrology institute, a national bureau of standards, or a national bureau of weights and measures. Some countries do not have national standards.

The primary standard is:

a standard which is widely accepted as having the highest metrological qualities and whose values ​​are accepted without reference to other standards of the same quantity.

Examples of primary standards are Josephson devices for realizing the “volt” value or stabilizing lasers with interferometers for realizing the “length” value. These instruments are used as national standards by many national metrology institutes and some well-equipped calibration laboratories.

The secondary standard is:

a standard whose value is assigned by comparison with a primary standard of the same value. Typically, primary standards are used to calibrate secondary standards.

The working standard is:

a standard that is used for routine calibration or verification of material measures, measuring instruments or standard samples.

Typically the working standard is calibrated against a secondary standard. The working standard used in everyday work to ensure that measurements are taken correctly is called a verification standard.

Does not exist general requirement regarding the accuracy of the working standard. It may be quite good as a reference standard in one place, or even as a national standard in another place.

There are classes of weights, starting with E1 - as the highest class, followed by E2, Fl, F2, Ml, M2, M3. A set of balances with accuracy class E2 can serve as a working standard in a calibration laboratory for calibration of a set of balances with accuracy class F1 or lower. The E2 set can serve as a reference standard in another laboratory that primarily calibrates balances to class F2 or lower. A set of E2 precision scales can be used as a national standard in a country where there is no demand for more accurate mass measurements than F1.

It should be noted that the accuracy of some measuring instruments used in industry is so high that even primary standards need to be calibrated.

The original standard is:

a standard having, as a rule, the highest metrological properties, available at a given place or in a given organization, in accordance with which the unit size is obtained from measurements performed at that place.

Calibration laboratories use reference standards to calibrate their working standards.

The comparison standard is:

a standard used as an intermediate standard for comparing standards.

Resistors are used as reference standards to compare voltage standards. Weights are used to compare lever scales.

The mobile standard is:

a standard, sometimes of a special design, intended for transportation, and used for comparing standards with each other.

A portable frequency standard powered by a cesium battery can be used as a mobile frequency standard. Calibrated load cells (load cells) are used as mobile force standards.

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