Talk:Unit of measurement/Archive 1

Decimal vs Metric vs SI vs MKS vs CGS
I can't help feeling that the Metric System should discuss SI (mks) rather than (cgs). Perhaps it needs an introduction that starts with the decimal system, followed by the Metric System and leading to SI (mks)? Icairns 17:42, 25 Jun 2004 (UTC)

Units of Measure vs Units of Measurement
Either the article Units of measurement or the category Units of measure needs to change name for consistency. Thoughts please. Icairns 17:42, 25 Jun 2004 (UTC)

I propose moving this article to Standard of Measurement, as it is really about the defacto Standard, SI. Thus a Standard of Measurement will have its global connotation about comparison to a standard, and the Unit of Measure (UoM) can retain its local usage in solving problems. Then the sequence of development can be clarified: Ancheta Wis 00:28, 31 Oct 2004 (UTC)
 * 1) statement of a problem
 * 2) characterizing the situation with appropriate Units of Measure and other appropriate concepts
 * 3) problem solution
 * 4) recognition of the Standards (the subject of this article) which apply to the problem, conversion to universal or other appropriate concepts
 * 5) re-statement of the problem, situation, solution for the reference documentation
 * 6) communication of the standard of measurement and re-translation to other, local situations (perhaps in local Units of Measure)

Japanese units
I saw reference recently to Japan having a different set of measurements than the SI or Imperial units. A quick googling about didn't yield any enlightenment, so I figured I'd ask y'all if you'd any insight.
 * Yes, they do but they're almost unused these day. I'm meaning to write an article on them one day. Jimp 23Sep05
 * de:Alte Maße und Gewichte (Japan) should be easy to understand or even translate, even if you don’t speak German. Christoph Päper 14:01, 25 September 2005 (UTC)
 * Thanx Crissov, I'll have to get onto it I've also got a weights & measures page in a Japanese-English dictionary of mine that'll probably prove handy in this respect. Jimp 4Oct2005
 * I've made a start. Jimp 25Oct2005

Non-SI units in the example
To any who think that the example should have SI units: I used non-SI units for a very good reason: conversion between SI units is so simple as to be considered trivial. It is easier to see the value of the rigorous method of unit conversion presented when the relationship between the different units is not in simple factors of ten.--BlackGriffen - Hi, I absolutely agree on not using SI for the example, see the concept I explain in my part on conversion of units. I think that concept is the right meaning for the term ``unit conversion''. If you don't agree, change the name, don't remove the concept.--RitaBijlsma

Merge
I really enjoyed reading this page, it's a very important one. Like many others, I have coded-up unit/quantity manipulation libraries so this fundamental theory page is very relevent. I can understand the argument to merge this with "units of measurement", that page not adding very much extra.

I would like to see linked pages to each identified system of measurement, having a common template for each abstract dimension, and showing conversion ratio's from that system to SI. This would be an extremely useful reference for Scientists and Engineers. I'm a wiki novice, not able to do this work justice myself.

I have also enjoyed some of the discussion pages about ancient systems, particularly useful in Archeological work rather than just Engineering. I know there is a lot of discussion about ancient systems of length, it would be good to get this sorted out too.


 * I agree that it should be merged. However, there is much here and at Units of measurement which doubles up on the content of SI, Historical weights and measures, Imperial unit, US customary units and English unit.  These pages need major sorting out.


 * Jimp 24Sep05


 * I've merged them. Jimp 25Sep05

Precision of unit conversions
I've removed this from the article.

"Thus conversion factors between units are always imprecise to some level and improved values may be found when a more precise comparison is performed."

Isn't 1 cm precisely 10 mm ... or 1 inch precisely 25.4 mm for that matter?

Jimp 24Sep05

Reorganisation
210.237.26.133 is me, Jimp, somehow I can't log in. Never fear, I'm not vandalising this article. I'm merely trying to improve it. Here's a breif history of today's edits.


 * 1) SI units - rewrite kg section: This had been poorly written and, worse, misleading. It doesn't matter whether it's on Earth or not; a litre of water has a mass (kilograms are mass units not weight units) of one kilogram as long as the thermodynamic conditions are right.  Though this is approximate.  See SI.
 * 2) Units and standards of the metric system: As above also I say "approximate" though it had been exact between 1901 and 1964. Again see SI.
 * 3) Imperial and US Customary units - replace subtitle as this applies (or fails to do) equally to traditional units other to the English ones: I had placed this section under the "Imperial and US Customary Units" however it applies not only to English units but to many other traditional European systems. Later I would put it under "History".
 * 4) Units of time and angle - move this back: I had put this in a seperate section because degrees of arc and time units are not specific to the English systems. Now that the section was split back up it could be moved back.
 * 5) Units of mass - move back: As above - that was the cut this was the paste.
 * 6) See also: added a pertenant link though this page may be merged here.
 * 7) Rewrite intro: I mostly aimed to improve the flow but did end up cutting out some stuff that didn't seem important enough of an intro.
 * 8) minor edit
 * 9) The origin of traditional units of measure - move into "History": This section deals with history so it belongs here (see above).
 * 10) History: As above again - that was the cut this was the paste.

If you disagree with anything I've done, Jtkiefer, please discuss it. Jimp 24Sep05

Rewrite SI units
I've removed the following.


 * The unit of length (or distance or linear size) is the metre (m), with related units including kilometre, centimetre, millimetre.


 * The unit of volume is the cubic metre (m³), although the litre is also used mostly for water, petrol and other liquid. A litre is equal to a 10 cm by 10 cm by 10 cm cube or a cubic decimetre. A millilitre (ml) is a 1 cm by 1 cm by 1 cm cube - this is also called cubic centimetre or one cc.  Cooks often use this measurement. A typical teaspoon is about 5 ml in size.


 * The unit of mass is the kilogram (kg). One litre of pure distilled water at its densest (+3.98 degrees Celsius) under standard atmospheric pressure has a mass of approximately one kilogram. The tonne is 1000 kilograms, or a million grams.


 * The unit of time is the second (s). The minute (60 seconds) and hour (60 minutes or 3600 seconds) are larger units. The day is usually said to be 24 hours, but is actually a tiny bit longer. This difference is corrected at the end of every year. A week (7 days) and month are also standards in most places, but there are different calendars. These are not part of the SI system, but are used in finance and other industries that set some standards.


 * The unit of force is called the Newton (N).

It wasn't well written. It included a seemably random rag-tag assemblage of units some base units other derived. I've replaced it with this.

However, as the preceeding paragraph contains the link to SI base units where this table is to be found, perhaps this table is redundant. Note: the same paragraph links to SI derived units also hence my deletion of volume and force units I see as justified. P.S. I've managed to log in now. Jimp 24Sep05

Future Plans
Here's some of what else I have in mind for this article.


 * 1) Merge The metric system section to Metric system.
 * 2) Summerise The metric system leaving this summery here with links to Metric system, SI'', &c.
 * 3) Merge History section to Historical weights and measures perhaps creating a third article about the History of measurement.

08:36 GMT 24 September 2005 Jimp


 * I am delighted that you have taken a strategic view of several articles. There is far too much overlap, duplication and inconsistency arising from article-centric editing. I think your proposals are sound. As far as I am concerned, you should be bold and do it. Would you like to contribute to the discussion about the random collection of articles for prefixed multiples? Bobblewik 13:47, 24 September 2005 (UTC)

Glad you agree. Yes, there is a lot of overlap. I would like to contribute to the discussion about the articles for prefixed multiples.

I've just finished numbers 1 & 2. Things are (in my opinion) better but still not ideal. There remains a great deal of overlap especially between SI and Metric system. Something will have to be done about this, however, Talk:Metric system is the best place to discuss this.

Number 3, though, is a little more involved. You've only got to look at Historical weights and measures, Talk:Historical weights and measures & the numerous archive to see what I mean. I shall discuss plan number 3 in greater detail at Talk:Historical weights and measures.

Jimp 25 September 2005


 * I agree with you that the SI base unit table will be redundant after a tidy up for the reasons you state. You are doing great work. Bobblewik 09:01, 27 September 2005 (UTC)

Split
The article at present is rather large and very diverse. Here are some possible solutions.


 * 1) Split out Systems of measurement into a new article and merge what remains of Historical weights and measures into this new article.
 * 2) Split out Calculations with units into a new article.
 * 3) Split out Base and derived units & put this content at Base unit.

After splitting a section out there'd be some tidying up to do this would probably include summarising what will have been moved leaving links to these new/existant articles and to other relevant articles, e.g. SI, Conversion of units, etc.

Of course, 1, 2 & 3 needn't depend on each other. Indeed what is probably the best approach might be to only do 1. This is what I'm about to do.

Both Units of measurement and Historical weights and measures (at present) deal with similar material viz. systems of measurement the only difference is that the latter is restricted to historical ones.

Both Units of measurement and Both Units of measurement, on the other hand are more closely tied to the units of measurement themselves. Thus, at least at present, these should probably stay here.

Jimp 5Oct05

Calculations with units

 * The section Units of measurement is almost incomprehensible to me. Although if I regard it as lesson in mathematics rather than anything peculiar to units, I can make some sense of the rambling text. I think it should either be deleted or revised (if somebody can work out what it is trying to say). Bobblewik 10:37, 5 October 2005 (UTC)

I'll see whether I can have a stab at it when I've got time. Jimp 12Oct05