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Lecture 1. Metrology as a science. Physical sizes. Measuring means. ass . N . I . Burmas. Outline. Metrology . The state service of metrology and standardization. 2. A physical size: essence, numerical value and units. 3. Basic and derivatives of PhS and their units.
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Lecture 1 Metrology as a science. Physical sizes. Measuring means. ass. N.I. Burmas
Outline Metrology. The state service of metrology and standardization. 2. A physical size: essence, numerical value and units. 3. Basic and derivatives of PhS and their units. 4. The system of units of PhS of CI. 5. The measuring means and them metrological descriptions (characteristics). Video - Introduction to the Study of Mechanical Measuremen
1. Metrology. The state service of metrology and standardization. • Metrology (from grec. tetron is a measure of and logos it is a word) is a science about a measurement, methods and means of ensuring of their unity and ways of achievement of necessary exactness. Consequently, metrology is studies (learning) about measures.
The assignment of metrology : • The measurement is finding of the physical size by an experimental way by the special of technical means. • The unity of measurements is such state of measurements , at which their results are shown in the legalized units and the errors of measurements are known with the given probability. • The exactness of measurements characterizes by approaching of their results to the actual meaning of the measuring size.
Metrology is divided into such kinds: • theoretical metrology; • practical (applied) metrology; • legal metrology;
The theoretical metrology is devoted to studying of the theoretical bases. • The practical (applied) metrology is devoted to the study of questions of practical application in the different spheres of activity of results of theoretical researches within the framework (limits) of metrological and positions of legal metrology.
The legal metrology includes the complexes of correlation general rules, requirements and norms, and also other questions which the require regulation and control from the side of the state, and directed on providing the unity of measurements and of the same type of means of the measurements .
Law „About metrology and metrological activity” • In 11 February, 1998 in Ukraine after 113//98-VR • The determines legal basics of providing the unity of measurements in Ukraine, regulates public relations in the sphere of metrological activity and directed on protecting of citizens and the national economy from the consequences of unreliable results of measurements.
The metrological service is a net of organizations, separate organization or separate subsection, on which the laid responsibility for the metrological providing of the measurements. The state system of standardization is the system, which determines a basic aim and principles of operation, forms and general organizational-technical rules of the performanceof all works with standardization.
The state metrological service enter: • accordingly subdivisions of central device of States consumer standartion of Ukraine • state scientific metrologic centers which belong to the sphere of operation of States consumer standartion of Ukraine: Kyiv – UkrCSM, Kharkiv – „Metrology”, Lviv – „System”, higher educational establishment • territorial organs of States consumer standartionof Ukraine are in Autonomous Republic of Crimea, region, Kyiv and Sevastopol and cities of regional submission, 35 DCSMS • The state service of the sole time and standard frequencies • The state service of standard samples of composition and properties of substances and materials • The state service of standard reference facts about physical to steel and properties of substances and materials
standardization Is an activity, which consists in establishment of positions for the general and multiple application in relation to present or possible tasks with an aim of achievement of optimum the degree of accordance of products, processes and services them to the functional setting, removal of barriers in the trade and assistance to the scientific-technical coheration.
Law of Ukraine “About standardization” may of 2001year for № 2408-111 sets legal and organizational principles of standardization in Ukraine and directed on providing of single technical policy in this sphere. Levels of standardization: • International standardization • Regional standardization • National standardization
The aim is providing of safety for life and health of man, animals, plants, and also property and guard of environment, make of conditions for the rational use of all types of national resources and accordance of objects of standardization to setting, assistance to the removal of technical barriers in trade. • Action of Law “About standardization” does not spread on the nuclear materials, pharmaceutical products, standards of medical service, record-keeping, education, and also other social standards, the sphere of action of which is put by the proper laws.
2. Aphysical size: essence, numerical value and units. • A physical size is the description of one property of a physical object (physical system, phenomenon or process), common of qualitative relation to many physical objects, but in the quantitative relation individual for every object.
The physical size (PhS) has qualitative and quantitative sides • The sort of a physical size is qualitative definiteness of a physical size. • The physical sizes which represent the same property in qualitative relation is the name of homogenous.
The dimensions of a physical size is quantitative definiteness of a physical size, what inherent to the concrete material object, system, phenomenon or process. • The value of a physical size is appraisal of the dimensions of a physical size as some number of the units accepted for it.
The value of physical size gets as a result of measurementsor calculation
The numerical value of a PhS. The unit of a PhS. • The numerical value of a PhS is a number which is included in the value of a size. • The unit of a PhS is a physical size of the fixed dimensions, which conditionally confer on numerical value is equal 1, applied for quantitative expression of homogeneous physical sizes. • The unit of a measurement of a PhS is a physical size, accepted to agreementfor basis for the quantitative valuation of sizes, homogenous with it in a qualitative relation. • A size of the unit of a measurement is quantity of a physical size which is contained in the unit of a measurement.
3. Basic and derivatives of a PhS and their units. Units of the measurement of a PhS choose as follows: • some quantity of units select of independently (basic) • other units put on the base of connections which exist between physical sizes (derivatives)
Basic PhS is a physical size which is included in the system of sizes and conditionally accepted in quality independently from other sizes of this system. • Derivative PhS is a physical size , which is included in the system of sizes and determined through the basic sizes of this system.
The dimension of PhS is expression which represents dependence of this derivative size on the basic sizes, in which the coefficient of proportion is accepted by equal to units. Size and dimension of units of PhS The size of an unit is a quantitative measure of a physical size which is contained in it. The dimension of an unit –put of correlates this derivative unit with basic units of the system.
4. The system of units of PhS of CI. • The system of units of physical sizes is combinatoin of basic and derivatives units of physical sizes, formed in accordance with the accepted principles for the put system of physical sizes. • The international system of units was entered in 1960 by XI general conference on measures and scales ( international brief name SI “CI”).
Additional basic units of the system of CI: • the flat angle - Radian rad • the corporal angle- Stheradian sr
5. The measuring means and them metrological descriptions (characteristics). • The mean of measuring technology (MMT) is the technical mean which is used during of measurementsand has the rationed metrological descriptions. The MMT belongs to: • means of measurements • measuring of devices
The mean of measurementsis the technical mean which is used at the measurementsand has the rationed metrological descriptions. The mean of measurementsrealizes the procedure of measurements. • The measuring device is the MMT, in which executed only one of component parts of the procedure of measurements(the measuring operation).
The measuring devices are: • the measure of PhS • to device of the equalization • the measuring of transformer • the scale measuring of transformer
the variation of proofs range of proofs of MM metrological reliability metrological refusal of MM the range of measurements of MM nominal valueof a measure the sensitiveness of MM the threshold of sensitiveness of MM the class of exactness The metrological characters of MMT are characteristics of properties of the MMT, which influence on results and errors of measurements.
