The content of measurement includes two parts of measurement and measurement. Measurement refers to the use of measuring instruments and tools to obtain a series of measurement data by measurement and calculation, or to reduce the topography of the earth's surface to a topographic map. Definition of Measurement 1. Early definition: The discipline that studies the shape and size of the Earth and determines the coordinates of the ground point. Thermolaminated Door,Thermolaminated Panels,Thermolaminated Doors Panels,Thermolaminated Accessories PRO CABINET SOLUTION PTY LTD , https://www.pcscabinet.com.au
2. Current definition: The discipline that studies the shape, size, location, direction, and distribution of various objects in three-dimensional space.
3. A more general definition: A measurement is a procedure or procedure that uses a suitable instrument to determine the magnitude of a given object on a given attribute. The amount as a measurement result is usually expressed by a numerical value. This value is determined by the ratio of the magnitude and the unit of measurement of a given dimension or scale system.
The content of measurement includes two parts of measurement and measurement. Measurement refers to the use of measuring instruments and tools to obtain a series of measurement data by measurement and calculation, or to reduce the topography of the earth's surface to a topographic map. The surveying and setting means that the position of the planned and designed buildings and structures on the drawings is marked on the ground as the basis for construction.
The four elements of measurement 1, the measurement object, that is, the measurement object. It is a thing or phenomenon that exists in the objective world. It is an object that we use numbers or symbols to express, explain, and explain.
2. Measure the content, that is, measure certain attributes or characteristics of the object. In fact, in any kind of measurement, the object we measure is an object, but the content measured is not the object itself, but the feature or attribute of the object.
3. The rule of measurement, that is, the rules of operation for expressing various attributes or characteristics of food using numbers and symbols. It can also be said that it is a specific operating procedure and a standard for distinguishing different features or attributes.
4. Numbers and symbols, ie the tools used to represent the measurement results. For example, 120cm, 350 yuan.
Measuring tool length - scale, vernier caliper, micrometer, gauge block, height gauge, indicator, ring gauge, regular
Quality - balance
Time - timer, stopwatch
Volume - measurement of liquid or irregular shaped solid steps: graduated cylinders & measuring cups.
Measurement combination measurement: If there are multiple measurements, although the measured (unknown quantity) has a certain functional relationship with some intermediate quantity, since the functional formula has multiple unknowns, it is impossible to measure one intermediate quantity. The value to be measured. At this time, some measurable different combinations can be obtained by changing the measurement conditions, and then the values ​​of these combinations are measured, and the simultaneous equations are solved to find the unknown measured.
Comparative measurement: A comparison method is a method in which a measured value is compared with a known similar metric on a comparator to obtain a measurement. This method is used for high accuracy measurements.
Zero method: The measured value is compared with the known quantity so that the difference between the two is zero. This method is called the zero method. Such as bridges, balances, steelyards, galvanometers
Offset method: The measurement is directly applied to the measuring mechanism to deflect or shift the pointer or the like to indicate the measured size.
Alternative method: the alternative method is to connect the measured quantity and the known quantity to the same measuring instrument successively. If the indication values ​​of the two measuring instruments are the same without changing the working state of the instrument, it is considered that the measured quantity is equal to the known quantity. For example, Cao Chong called the elephant.
Accumulation method: If the measured object is too small to measure a single object directly with a measuring instrument, measure the same size of the object and then average it, such as measuring the thickness of a piece of paper, a hair The diameter of the wire, the quality of a staple, etc.
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