Jump to content

User:Garamond Lethe/sandbox/kmh

From Wikipedia, the free encyclopedia

A Bit of Background

[edit]

There's a wonderfully strange dispute going on over how this article should be written. The existing version treats "km/h" as kilometre per hour / kilometer per hour and then describes the two standard unit symbols. However, the name of the article is not "kilometre per hour", but "km/h". The latter string has a history intertwined with (but distinct from) "kilometre per hour": "km/h" is one of several abbreviations used before (and after) international standardization occurred, and standardization has created a body of rules by which "km/h" must be constructed and represented (down to specifying how the [solidus] may and may not be used and the requirement of an upright Roman typeface).

This distinction (so far unspoken, to the best of my knowledge) has resulted in a bifurcation of the focus of the article. For example, the European Union may have adopted the units "kilometers per hour" to be used in specific areas, but that would more properly be noted in an article on "kilometers per hour", not "km/h". Pointing out that existing dictionaries continue to treat "km/h" as an abbreviation instead of a symbol has very little to do with the definition and standardization of "kilometers per hour", but is a useful and interesting datapoint in the evolution of "km/h".

Elsewhere I had proposed that the article be split in two: km/h (Unit Symbol) and km/h (pre- and non-SI uses). A more natural split might be kilometers per hour and km/h. While I think both can find a home within one article, it may helpful to editors to remind them that there are two distinct concepts in play. GaramondLethe 16:50, 12 July 2012 (UTC)

RFC

[edit]

At least one editor would like to resolve the focus problem using RFC. I'll be starting a draft of that here.

Use of kph in the EU

[edit]

User:Garamond Lethe/sandbox/kph

Current Lead

[edit]

The kilometre per hour (American English: kilometer per hour) (unit symbol km/h or km·h−1) is a unit of speed, expressing the number of kilometres travelled in one hour.

Lead

[edit]

km/h is one of several abbreviations for and one of two standard symbols of the unit of speed "kilometers per hour".

Compromise lead

[edit]

The kilometre per hour (American English: kilometer per hour) ([[SI] symbols km/h, km h-1 and km•h-1) is a unit of speed, expressing the number of kilometres travelled in one hour. English-language abbreviations in current use include "km/h", "kmph" and "km/hr".


km/h as an abbreviation

[edit]

Although the unit of length kilometer first made its appearance in English in 1810[1], the compound unit of speed "kilometers per hour" was first observed no later than 1866[2]. "Kilometers per hour" did not begin to be abbreviated in print until many years later, with several different abbreviations existing near-contemporaneously.

Current accepted abbreviations are listed below. Note that some of these abbreviations may be limited in scope to specific domains, such as the United State military.


km/h as a symbol

[edit]

A desire for standarization of weights and measures across international borders led to the creation of the General Conference on Weights and Measures (CGPM) whose first conference in 1889 sanctioned international prototypes for the meter and the kilogram. In 1927, the seventh CGPM conference further refined the definition of the meter and, with the seventh resolution of the 9th conference (1948) several symbols were associated with units, including the symbol m for meter and h for hour. The 11th conference of the CGPM (1960) selected six units, including the meter, to be considered as an International System of Units (SI) along with a standarized set of prefixes and their corresponding symbols (including kilo (k) for a multiplying factor of 1000).[29] Note that while the second was defined as the base unit of time during this process, the hour was not defined as either a base unit or supplemental unit and is defined instead as a Unit in use with the International System along with minute and day.[30] There are two methods for indicating a compound unit is the quotient of two or more units. A solidus may separate the units, thus producing km/h, or a negative exponent may be used along with either a space or a dot between units, thus km h-1. Note that conformance to the standard requires use of a Roman (upright) font. The symbol must not be changed to indicate a plural and no space should be left between a unit symbol and its prefix.[30]

The SI explicitly states that unit symbols are not abbreviations and are to be written using a very specific set of rules.[30] M. Danloux-Dumesnils[31] provides the following justification for this distinction:

It has already been stated that, according to Maxwell, when we write down the result of a measurement, the numerical value multiplies the unit. Hence the name of the unit can be replaced by a kind of algebraic symbol, which is shorter and easier to use in formulae. This symbol is not merely an abbreviation but a symbol which, like chemical symbols, must be used in a precise and prescribed manner.

Regulatory use of km/h

[edit]

In 1988 the United States National Highway Traffic Safety Administration promulgated a rule stating that "MPH and/or km/h" were to be used in speedometer displays. On May 15, 2000 this was clarified to read "MPH, or MPH and km/h".[32] However, the Federal Motor Vehicle Safety Standard number 101 ("Controls and Displays") allows "any combination of upper- and lowercase letters" to represent the units.[33]

EU directive 75/443/EEC which regulates the layout of speedometers within the European Union, uses the text "km/h" in all languages.

Notes

[edit]

Google books lists volume 86 of the Smithsonian Meteorological Tables[34] has having been published in 1862. If this was correct, this would be the first reported use of kilometer per hour in English. However, the fifth revised edition[35] (Jan. 1931) states the original edition was published in 1893; this appears to be the correct date.

If the 1898 date for "km/h" turns out to be suspect, this later date may be used instead.

"Metre" has been silently regularized to "Meter" throughout.

References

[edit]
  1. ^ "The Oxford English Dictionary". Retrieved July 13, 2012.
  2. ^ Frazer, John F. (November 1866). Journal of the Franklin Institute of the State of Pennsylvania for the Promotion of the Mechanic Arts. Vol. LII. Philedelphia: Franklin Institute. p. 314.{{cite book}}: CS1 maint: date and year (link)
  3. ^ Harrington, Mark W., Rotch, A. Lawrence and Herdman, W. J. (May 1889). American meteorological journal: A monthly review of meteorology, medical climatology and geography. Vol. 6. Meteorological Journal Company. p. 226.{{cite book}}: CS1 maint: date and year (link) CS1 maint: multiple names: authors list (link)
  4. ^ Pell-r, G. (?) (February 1895). "Power consumed on electric railways". The Street Railway Journal. 11 (2): 116–117.{{cite journal}}: CS1 maint: date and year (link)
  5. ^ Bulletin - United States Geological Survey, Volumes 151-152. USGS. 1898. pp. ix.
  6. ^ Whipple, F. J. W. (1899). "The Stability of the Motion of a Bicycle". The Quarterly Journal of Pure and Applied Mathematics. 30: 342.
  7. ^ Whipple, F. J. W. (1899). "The Stability of the Motion of a Bicycle". The Quarterly Journal of Pure and Applied Mathematics. 30: 333.
  8. ^ Launhardt, Wilhelm (1900). The Theory of the Trace: Being a Discussion of the Principles of Location. Lawrence Asylum Press. p. 55.
  9. ^ Swinburne, J. (June 1902). "The Electrical Problem of Railways". The Railway Engineer. 23 (6): 184.{{cite journal}}: CS1 maint: date and year (link)
  10. ^ Ball, Jack (August 1911). "Foreign Notes on Aviation". Town & Country: 26.{{cite journal}}: CS1 maint: date and year (link)
  11. ^ Brooklyn Daily Eagle Almanac. Brooklyn Daily Eagle. 1912. p. 504.
  12. ^ Dodd, S. T. (Jan 1914). "A Review of Some European Electric Locomotive Designs". General Electric Review. 17 (1): 1141.{{cite journal}}: CS1 maint: date and year (link)
  13. ^ a b "Data on Mixed Motor Fuels of Interest for American Export Trade". The Automobile. 33 (15): 709. October 1915.{{cite journal}}: CS1 maint: date and year (link)
  14. ^ "Tractive resistance tests with an electric motor truck". Engineering and Contracting. 46 (25): 560. December 1916.{{cite journal}}: CS1 maint: date and year (link)
  15. ^ Eason, Alec B. (1919). Flow and Measurement of Air and Gases. Charles Griffin and Company Limited. p. 222.
  16. ^ Cooper, S. B. (November 1921). "The Paulista Railway Electrification". Railway and Locomotive Engineering. 34 (1): 306.{{cite journal}}: CS1 maint: date and year (link)
  17. ^ Aircraft Year Book. Vol. 15. Aerospace Industries Association of America, Manufacturers Aircraft Association, Aeronautical Chamber of Commerce of America. 1933. pp. 391–393.
  18. ^ Barr, Chris (2010). The Yahoo! Style Guide. St. Martin's Griffin. p. 528. ISBN 978-0312569846.
  19. ^ a b American Heritage Abbreviations Dictionary. Houghton Mifflin. 2002. p. 160. ISBN 0618249524.
  20. ^ The Rosen Comprehensive Dictionary of Math. The Rosen Publishing Group. 2008. p. 118. ISBN 9781404206991.
  21. ^ "Manual on Uniform Traffic Control Devices for Streets and Highways" (PDF). US Department of Transportation, Federal Highway Administration. 2003. pp. A-15. Retrieved July 14, 2012.
  22. ^ Webster's II New College Dictionary. Houghton Mifflin. 2001. p. 1292. ISBN 0395708699.
  23. ^ The Associated Press Stylebook and Briefing on Media Law 2011. Basic Books. 2011. p. 154. ISBN 9780465021871. {{cite book}}: Unknown parameter |agency= ignored (help)
  24. ^ Vlietstra, Jakob (2001). Dictionary of Acronyms and Technical Abbreviations: For Information and Communication Technologies and Related Areas. Springer. p. 332. ISBN 1852333979.
  25. ^ The US Department of Defense (2009). The Dictionary Of Military Terms. Skyhorse Publishing. pp. A-83. ISBN 9781602396715.
  26. ^ Websters Guide to Abbreviations. Merriam Webster. 1985. p. 289. ISBN 0877790728.
  27. ^ a b United States Defense and Intelligence Abbreviations and Acronyms Handbook. International Business Publications. 2006. p. 120. ISBN 9780739744741.
  28. ^ Cutler, Deborah W. and Cutler, Thomas J. (2005). Dictionary of Naval Abbreviations. Naval Institute Press. p. 215.{{cite book}}: CS1 maint: multiple names: authors list (link)
  29. ^ Page, Chester H. and Vigoureux, Paul (1971). The International System of Units (SI): National Bureau of Standards Special Publication 330. United States Department of Commerce.{{cite book}}: CS1 maint: multiple names: authors list (link)
  30. ^ a b c Standard for Use of the International System of Units (SI): The Modern Metric System (IEEE/ASTM SI 10-1997). Institute of Electrical and Electronics Engineers, Inc. 1997. p. 7.
  31. ^ Danloux-Dumesnils (1969). The Metric System: A Critical Study of its Principles and Practice. The Athlone Press of the University of London. p. 32.
  32. ^ National Highway Traffic Safety Administration (May 2000). "Federal Motor Vehicle Safety Standards; FMVSS 101--Technical Correction--Speedometer Display". Federal Register. 64 (94): 30915–30918.{{cite journal}}: CS1 maint: date and year (link)
  33. ^ National Highway Traffic Safety Administration. Federal Motor Vehicle Safety Standard (101: Controls and Displays). p. 237.
  34. ^ Smithsonian Meteorological Tables. Smithsonian Institution. 1862 (?). {{cite book}}: Check date values in: |year= (help)CS1 maint: year (link)
  35. ^ Smithsonian Meteorological Tables (5th (revised) ed.). Smithsonian Institution. 1931.
  36. ^ Pocket Companion for Engineers, Architects, Builders (16th ed.). Carnegie Steel Company. 1913. p. 341.
Retrieved from "https://en.wikipedia.org/w/index.php?title=User:Garamond_Lethe/sandbox/kmh&oldid=1168387138"