{"title":"如何从具有固定数值的七个常数出发,定义修订版 SI 的单位。","authors":"Richard S Davis","doi":"10.6028/jres.123.021","DOIUrl":null,"url":null,"abstract":"<p><p>As part of a revision to the International System of Units (SI) approved in 2018 and to take effect in May 2019, the seven base units will be defined by giving fixed numerical values to seven defining constants. This article shows how the definitions of all seven base units can be derived efficiently from the defining constants, with the result appearing as a table. The table's form makes evident a number of connections between the defining constants and the base units. Appendices show how the same methodology could have been used to define the same base units in the present SI, as well as the mathematics that underpins the methodology. Since the base units are now defined in terms of constants, then all units in the SI are now defined in terms of those constants.</p>","PeriodicalId":54766,"journal":{"name":"Journal of Research of the National Institute of Standards and Technology","volume":"123 ","pages":"1-11"},"PeriodicalIF":1.3000,"publicationDate":"2018-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7339751/pdf/jres-123-021.pdf","citationCount":"0","resultStr":"{\"title\":\"How to Define the Units of the Revised SI Starting from Seven Constants with Fixed Numerical Values.\",\"authors\":\"Richard S Davis\",\"doi\":\"10.6028/jres.123.021\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>As part of a revision to the International System of Units (SI) approved in 2018 and to take effect in May 2019, the seven base units will be defined by giving fixed numerical values to seven defining constants. This article shows how the definitions of all seven base units can be derived efficiently from the defining constants, with the result appearing as a table. The table's form makes evident a number of connections between the defining constants and the base units. Appendices show how the same methodology could have been used to define the same base units in the present SI, as well as the mathematics that underpins the methodology. Since the base units are now defined in terms of constants, then all units in the SI are now defined in terms of those constants.</p>\",\"PeriodicalId\":54766,\"journal\":{\"name\":\"Journal of Research of the National Institute of Standards and Technology\",\"volume\":\"123 \",\"pages\":\"1-11\"},\"PeriodicalIF\":1.3000,\"publicationDate\":\"2018-12-03\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7339751/pdf/jres-123-021.pdf\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Research of the National Institute of Standards and Technology\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://doi.org/10.6028/jres.123.021\",\"RegionNum\":4,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"2018/1/1 0:00:00\",\"PubModel\":\"eCollection\",\"JCR\":\"Q3\",\"JCRName\":\"INSTRUMENTS & INSTRUMENTATION\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Research of the National Institute of Standards and Technology","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.6028/jres.123.021","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2018/1/1 0:00:00","PubModel":"eCollection","JCR":"Q3","JCRName":"INSTRUMENTS & INSTRUMENTATION","Score":null,"Total":0}
How to Define the Units of the Revised SI Starting from Seven Constants with Fixed Numerical Values.
As part of a revision to the International System of Units (SI) approved in 2018 and to take effect in May 2019, the seven base units will be defined by giving fixed numerical values to seven defining constants. This article shows how the definitions of all seven base units can be derived efficiently from the defining constants, with the result appearing as a table. The table's form makes evident a number of connections between the defining constants and the base units. Appendices show how the same methodology could have been used to define the same base units in the present SI, as well as the mathematics that underpins the methodology. Since the base units are now defined in terms of constants, then all units in the SI are now defined in terms of those constants.
期刊介绍:
The Journal of Research of the National Institute of Standards and Technology is the flagship publication of the National Institute of Standards and Technology. It has been published under various titles and forms since 1904, with its roots as Scientific Papers issued as the Bulletin of the Bureau of Standards.
In 1928, the Scientific Papers were combined with Technologic Papers, which reported results of investigations of material and methods of testing. This new publication was titled the Bureau of Standards Journal of Research.
The Journal of Research of NIST reports NIST research and development in metrology and related fields of physical science, engineering, applied mathematics, statistics, biotechnology, information technology.