Similarities and differences between measurement and metrology

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I. What is measurement? According to JJF1001-1998 \"General Terms and Definitions in Metrology\", the definition of measurement is: a set of operations carried out with the aim of determining a quantity value (Note: 1. The operations can be carried out automatically.) 2. Measurement is sometimes also referred to as quantification). In JJG1001-82 \"General Terms and Definitions in Metrology\", the definition of measurement is: the experimental process carried out to determine the quantity value of the object under measurement. The core of both definitions is the determination of a quantity value, and a new term \"quantity value\" is introduced here. The definition of a quantity is: the product of a numerical value and a unit of measurement. Now, VIM has a new revised version, namely the international standard \"ISO/IEC Guide 99:2007 International Vocabulary of Metrology —— Basic and general concepts and associated terms\", VIM. JJF1001-1998 is currently under revision. In the new international standard VIM2.1, the definition of measurement is: “The process of obtaining values through experiments, and of reasonably assigning one or more values to a quantity.” ”The concept of this definition has been refined; the quantity it refers to is not merely the product of a numerical value and a unit of measurement. Instead, a \"quantity value\" (VIM 1.19) refers to the magnitude of a quantity expressed together with a numerical value and a reference object. ”The definition note for a quantity states that a quantity can be expressed in various ways; depending on the type of reference object, it can be represented as the product of a number and a unit of measurement ； When the dimension is 1, the unit of measurement 1 usually does not indicate anything ； A number and a measurement procedure that serves as a reference ； A number and a reference material. In the definition note for measurement, it is explicitly stated that “measurement means the comparison of quantities and includes the counting of entities.” ”In fact, people also refer to this process of comparing quantities in a broad sense as “measurement”. For example, in the early days of industry, calipers were used to measure the thickness of shafts; they did not provide numerical values, only allowing for comparisons between sizes. It is also quite common in today’s industrial production to use gauges to measure products. It can only grasp concepts such as “pass” and “fail,” “working” and “not working,” “qualified” and “unqualified,” and it does not provide any numerical values. For example, using a spectrometer to measure trace elements allows one to determine only whether they are present or not, but not their concentration. With the development of society, in order to unify everyone’s understanding of the same thing, units of measurement emerged; these units are all derived from nature. For example, using the size of a certain part of the human body as a unit of length measurement ； The time it takes for a stick of incense to burn is used as the unit of measurement. Different ** and their various historical periods have different units of measurement. With the increase in international interactions, internationally standardized units of measurement have emerged. This broad concept of a reference object can cover not only the fields of industry and science, but also various aspects such as humanities, society, language, and culture. In China’s \"Handan\", the definition of measurement is: [measure; survey; gauge; determine] the use of instruments to determine the terrain, the location of objects, or physical quantities such as temperature, speed, and function. An example sentence is: Measure the depth, height, and width of the cabinet. Here, the noun “determination” is used in place of “measurement,” although determination is actually a synonym for measurement. Where the term “measurement” can be found in ancient texts, the Han Dictionary explains it as follows: In Yuan Hong’s ‘Records of the Later Han Dynasty · Biography of Emperor Ling I’, it is said that \"Shudu is as vast as waves covering tens of thousands of acres; trying to clarify it doesn’t make it clear, and trying to turbid it doesn’t make it turbid. Its depth and breadth are such that it is difficult to measure.\" ”Wei Zhuang of the Former Shu Dynasty, in his work “A Hundred Verses on Reflections on Autumn Events, Composed in Response to Zheng Shiyi”: “The fate of the nation is full of perils; how can one fathom the will of heaven?” ”Song Ye Shi, “Record of the Yeling Study”: “The breadth and vastness of books are indeed immeasurable.” ” II. What is metrology? According to JJF1001-1998, metrology is defined as: “Activities aimed at ensuring uniformity of units and the accuracy and reliability of measured values.” ” In JJG1001-82, there is only a definition of metrology, but no definition of measurement. Metrology is defined as the science that deals with measurement, as well as ensuring the uniformity and accuracy of measurements (Note: Metrology focuses on measurement units, as well as the establishment, preservation, and use of standards for them) ； Measurement methods and measuring instruments ； Accuracy of measurement ； The observer’s ability to make measurements ； As well as measurement systems and management, etc. Metrology also includes the study of physical constants and reference materials, as well as the accurate determination of material properties. Judging from the structure of the English word “metrology”, it should be “metrology” rather than “measurement”. In VIM 2.2, the definition of metrology is “the science of measurement and its applications”. The English word “measurement” can sometimes be interpreted as measurement. Based on modern metrological perspectives, the author’s understanding of \"metrology\" is: all the activities aimed at ensuring that measurement values can be accurately transmitted from standards to all measured quantities, or that all measured quantities can be accurately traced back to those standards. These activities include all measurement tasks, as well as management tasks and scientific research related to metrology; all of these fall within the scope of metrology. This understanding is consistent with the definition of \"metrology\" in JJF1001-1998 and the upcoming revised version JJF1001-201x, \"General Terms and Definitions in Metrology\" – namely, \"activities aimed at achieving unit consistency and accurate and reliable measurement values.\" It merely makes the “activity” in the definition of “measurement” more specific. In China’s \"Handan\", the definition of measurement is [measure and calculate; estimate]: comparing a quantity that is currently unknown with a known quantity in order to determine its size, length, weight, etc. This content is very similar to the definition of measurement, but it does not reflect the essential aspects of metrology. Where the term “measurement” can be found in ancient texts is explained in the \"Han Dictionary\". From The Book of Guanzi, Zhou He: “Heaven is bright and radiant; there is no measure for it.” ； Geology, chemistry, biology – no Panya. ”Dai Wang made the correction: “Ding Yun: ‘Yang should mean to nurture.’” Pseudographic characters. ’”The Sutra of the Bodhisattva Moonlight as Spoken by the Buddha states: “The Tathagata attains perfect enlightenment free from attachment, bringing immeasurable benefits to the world; he accumulates merits in order to save all beings.” ”Tang Shenyi’s “Biography of the Physician Guo Chang” states: “Chang said, ‘Merchants are people with narrow perspectives and limited vision. They spend their days striving to make sales and purchases; they calculate every single ounce and gram. Yet what they earn still falls short of their expectations.’ ’”Yuan Hongdao of the Ming dynasty wrote in his Letter to Tao Shikuì: “What’s the difference between this and worms in an ox’s stomach, trying to measure the breadth, width, length, and depth of the universe?” ”The term “measurement” used in these places implies the act of measuring, but it does not carry the meaning of measurement as understood today. In our country, the term “metrology” was first used in accordance with its quantitative definition. According to relevant documents, in September 1936, Wu Chengluo, then director of the **National Bureau of Weights and Measures of the Republic of China, delivered a radio speech titled “The New System of Weights and Measures,” which was later published in ‘Industrial Standards and Weights and Measures’ (a monthly magazine, Volume 3, Issue 4, published on October 30, 1936). The text uses the term “measurement” repeatedly as a fixed word, and specific terms such as “measurement,” “measurement unit,” “measurement standard,” and “metrology” appear (for the relevant paragraphs, please refer to the article titled “Tracing the Origin of the Term ‘Measurement’ — A Review of the Development of Definitions for This Term in China,” published in the 3rd issue of this journal in 2010). From the above, it can be understood that “measurement” has two meanings; namely, measurement refers to determining the magnitude of a quantity using a standard instrument with a defined unit ； It refers to the concept of generalized quantities that exceed the scope of measurement. III. Similarities and differences between metrology and measurement Metrology and measurement are two terms with very similar meanings; to a large extent, they have the same significance. However, metrology cannot be equated with measurement, nor can measurement be equated with metrology. In modern society, in order to exchange measurement results, unified measurement units and measures to ensure consistency of values are necessary. Therefore, in modern society, the measurement of all physical, chemical, and biological quantities is related to metrology. The purpose of metrology is to enable the measurement results of each object under test to be traced back to the values of the standards. There are some measurements whose units are rather arbitrary, but they have nothing to do with metrology. For example, the measurement of customer satisfaction: the process of comparing this value fits the definition of measurement, but it has nothing to do with quantification. Moreover, the management work in measurement has nothing to do with actual measuring. If we use mathematics to describe these two terms, their defined ranges can be represented by two sets, with neither set covering the other. A large part of them intersect. The overlapping parts share the same concept, while the non-overlapping parts represent distinct categories. Therefore, when using these two terms, one must pay attention to the context in which they are used. In certain situations, only “metrology” or only “measurement” can be used; otherwise, the intended meaning may not be conveyed properly. In translation, when converting from Chinese to English, it is important to decide whether to use \"metrology\" or \"measurement\" or \"measure\" for the term related to measurement. When translating from English to Chinese, it is important to pay attention to deciding whether to use \" Measurement \" or \" Measurement \" for \"measurement\" or \"measure\".