Чтение онлайн

Non-commercial measurement details used to be academic curiosities. The development of standards follows the needs of technology. As a r esult, some units of measure have much more resolution than others. The second is reproducible to 1 part in 1014. As it became possible to measure time more precisely, solar time, believed to be a constant, proved to be very slightly irregular. This resulted in leap second adjustments to keep UTC (universal time coordinate) synchronized with solar time. The candela standard is difficult to recreate. An incandescent bulb design must be used as a secondary standard, a transfer standard. These special candela standard bulbs recreate the candela when a sp ecific amount of current is applied. Luminance (candela) can only be reproduced to 5 % of reading despite having sensors that have accuracies of +/– 50 parts per million (0.005 %) precision. This is due to the standard not being accurately reproducible.

Temperature (kelvin) is defined by agreed fixed points. These points are defined by the state changes of nearly pure materials, generally as they move from liquid to solid. Between these fixed points, Standard Platinum Resistance Thermometers (SPRTs) are used to interpolate temperature values. This mosaic of approaches produces measurement uncertainty which is not uniform over the entire range of temperature measurement. Temperature measurement is coordinated by the International Practical Temperature Scale, maintained by the BIPM.

Ex. 2. Answer the following questions

1. What was learned later about the Earth’s surface ?

2. How many unites of measure are internationally recognized currently ?

3. What is Standard Platinum Thermometer used for ?

4. What do special candela standard bulbs recreate ?

5. What are any measurements based on?

Ex. 3. Are these sentences true or false ?

1. Non-commercial measurement details were studied by scientists.

2. The candela standard is easy to recreate.

3. Voltage and resistance units are independent on current units.

4. Temperature (kelvin) is defined by non-defined fixed points.

5. Standard Platinum Resistance Thermometers (SPRTs) ar e used to interpolate voltage values.

6. Watt is derived from meter.

7. Ten independent units of measure are internationally recognized, currently.

Ex. 4. Fill the blanks using the following word words:

surface, poles, to define, reason, to attempt, length, to reproduce, metrology object.

Standard is an … oridea that can be used some accepted … Ideal standards can be … without uncertainty. The first ideal standard was … to create in the 19th century. It was connected with «meter» … standard. In the 19th century meter was … as one ten-millionth of the distance from the equator to one of the Earth’s … It was considered as the first ideal standard. Later it was learned that the Earth’s … an unreliable basis for a standard because the Earth could change its shape. Today there are carried out many calibration investigations w hich are widely used in … for establishing standards.

Ex. 5. Match the beginning with the endings based on the text

Ex. 6. Put the questions to the bold-typed words:

1. These bulbs recreate candela.

2. Luminance (candela) can only be reproduced to 5 %.

3. This organization coordinates temperature measurements.

4. Current is applied during the recreation of candela.

5. This mosaic of approaches produces measurement uncertainty.

Ex. 7. Make the summary of the text: «The modern standards of some physical quantities» using the following plan:

The definition of ideal standard.

The definition of Candela standard and Kelvin standard.

requirement – требование – талап; бап; міндетті ереже

technical standards – нормативно-технические документы – дстрлі техникалы жаттар

technical system – техническая система – техникалы жйе

formal document – официальный документ – ресми жат

criterion – критерий (pl. criteria) – критерий, белгі

practice – методика – діс, діс – тсіл жиынтыы

certified reference standard – аттестованный стандартный образец, аттес-тованный эталонный образец – аттестацияланан стандартты лгі

certified reference material – аттестованный стандартный образец материала – материалды аттестациядан ткен стандартты лгісі

reference base – база стандартов – стандарттар негізі

national standard – государственный стандарт – мемлекеттік стандарт

national standards body – орган по разработке государственных стандартов – мемлекеттік стандарттарды жете зерттейтін йым paper

trail – документальное свидетельствo – ( деректі ), жатты

regulatory body – орган управления – басару органы

corporation – акционерная компания, корпорация – акционерлік серіктік, корпорация, бірлестік

military – армия – армия

mandatory – обязательный – мандатты; міндетті

to adopt – принимать – абылдау, абылдап алу; лгі алу, еліктеу

edict – указ – аулы

standard specification – стандартные технические условия – стандартты техникалы шарттар

explicit – точный – ыпты, тиянаты; дл тра

set – набор – жина, жиынты

procurement – закупка – толайым, сатып алу

precise – точный – тиянаты; шынды, дл, тура

standard test method – метод стандартного испытания – стандартты діс сынаы

standard practice – стандартная методика, стандартная технология – стандартты діс, стандартты технология

technical practice – техническая норма – техникалы млшер

nuclear power plant – ядерная энергетическая установка – ядролы энергетикалы ондыры

standard guide – указатель стандартов – стандарттар крсеткіші

standard unite – стандартная единица измерения – стандартты лшем бірлігі

options – дополнительная информация – осымша млімет

specific course of action – определенные действия – белгілі рекеттер

voluntary standard – рекомендательный (необязательный) стандарт – сыныс жасайтын (ерікті) стандарт