The simple fact, though, is that the size of a dot (or, more correctly, pixel) is not sufficient to tell us what a monitor's resolution is. The center-to-center distance between adjacent dots is what provides that information. So far, for monitors, nobody has proposed indicating that in other than millimeters (typically 0.28 mm), so I'm not sure why you use that as your example.
Liters per second (L/s) for toilet flushing is totally useless. Toilets have to conform to certain conservation requirements, for which the total amount of water used each time must be regulated. In that sense, liters per flush provides EXACTLY the information that is required. If you were to specify liters per second, you would also have to specify the flush duration in seconds (i.e., seconds per flush). Then you would have to multiply the two values in order to determine if the toilet conformed to the legal requirements. A little silly, don't you think? What on earth are we seeking here? Clarity or obscurity? Bill Potts, CMS Roseville, CA http://metric1.org [SI Navigator] -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Ma Be Sent: Thursday, January 31, 2002 10:03 To: U.S. Metric Association Subject: [USMA:17801] Re: Democracy and metrication And I must enthusiastically concur with Adrian here (once more!). We do need to stop creating all sorts of mechanisms measurementwise that defy logic and simplicity. Indeed, if the size of the dot is all that takes to express how fine the resolution of a monitor is, then why come up with some idiotic dpi??? If we can express flow of a toilet using standard values like l/s, why come up with some silly gal/F??? If we could express printing speed as m/s, why invent some ppm crap??? (But on a positive note, I started seeing a nice "new" measurement in the computer industry, the pL - picoliter - to express how fine bubble jet printers can print! Nice going, Canon! Hopefully this trend will catch up!...) I guess one must draw the line somewhere and stop this kind of lunacy, don't you think? Marcus On Wed, 30 Jan 2002 16:20:43 Adrian Jadic wrote: >You're in denial Bill! If they are not units of measure what are they? Can >you give me a definition for units of measure? What is the difference >between BTU and flushes? > >I am sorry to say but this thinking is a product of "everything goes" >school. I am not trying to be sarcastic or arrogant. Please try to >understand! You actually generated a false unit of measurement dot/cm. When >in fact the correct rating would be the dimension of the pixel in mm, or >submultiples. Do you see what I mean? Is there such unit as dot/cm in ISO or >SI? Just the fact that it uses cm does not make it a valid unit of >measurement! > >I was taught that when I build a tool I classify it by the strength of the >material, or by the dimensional characteristics and not by how many holes it >can drill per minute. And if I don't know how to characterize it I go and >ask the specialists at the national institute for standards. > >Rating of a product should have to do with fundamental units of measure >hence with fundamental physical properties. By generating a unit (or call it >what you want) as "ppm" one does exactly what the cups per minute does or >the gallons per flush. Creating a fictitious symbol in people's minds that >has nothing with physical properties. > >The only true UofM in computers is MHz which truly represents the frequency >of oscillation of the machine's "clock" which sets the speed for the chip. > > >A. > >-----Original Message----- >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On >Behalf Of Bill Potts >Sent: Wednesday, 30 January, 2002 15:27 >To: U.S. Metric Association >Subject: [USMA:17772] Re: Democracy and metrication > > >Adrian Jadic wrote: > >"The first and simplest example is the computer screen resolution. Although >the pixel size can be easily expressed in mm (0.15..etc.) as it is in Europe >the computer manufacturers have invented the dpi. Then they invented the bps >(baud per second) then the mips, the flops, the ppm (pages per minute) and >God knows how many are there that I don't know about." > >First, a pixel or a dot is an arbitrary element, not a unit of measure. In >expressing resolution in dots per inch, the industry is not creating a new >unit. Obviously, we would rather the measurement be dot/cm. > >In defining the resolution of a display, the significant measurement is dot >pitch (i.e., the distance from the center of one pixel to the center of the >adjacent pixel). That is specified only in millimeters (0.28 mm being a >common value). Monitor advertisements specifying "dpi" are written by people >who don't know what they're talking about, not by the manufacturers of the >monitors. (Most ads do get it right, however, and say "dot pitch: 0.28 mm".) > >Again, the bit is an arbitrary element (the binary digit) and not a unit of >measure. The term bps (bits per second -- a baud is already a rate, defined >as one change of state per second) is atrocious, of course, but the >standards bodies express it, correctly, as bit/s. > >Again, instructions (mips being "million instructions per second" and flops >being "floating point operations per second") are not units of measure > >Still again, pages are arbitrary. If one is buying a laser printer, it's >certainly necessary to know its performance in pages per minute. > >To reiterate, none of these terms introduces a new unit of measure. They >simply use existing units of measure in conjunction with arbitrary, but >necessary, elements or characteristics. > >Bill Potts, FBCS, CMS >Roseville, CA >http://metric1.org [SI Navigator] > > Is your boss reading your email? ....Probably Keep your messages private by using Lycos Mail. Sign up today at http://mail.lycos.com
