Re: pedagogically barren?
On Wed, 4 Jun 2003, Markus Kuhn wrote: > I asked Ron Beard, and he said that there were no plans for written > post-proceedings of this meeting. I personally would have liked very > much to end up with a written book of everything that was presented and > discussed. Yet again I am struck by how unfavourably the way the present proposals are going compares to the 1884 Meridian Conference. That produced 200 pages of well-argued proceedings, and the participants knew that it was for governments to decide any changes to legal practice after considering the recommendations of the conference, not for one body with its own agenda unilaterally to decide to change time signals and let governments pick up the pieces. -- Joseph S. Myers [EMAIL PROTECTED]
Re: pedagogically barren?
> A propos of both the topic and the discussion of notation, I've observed > that in the U.S., hospitals (where 24-hour notation, or "military time" as > civilians inevitably call it) are one of the few businesses where wall > clocks are nearly always set to the correct time (within+/- one minute, and > often within +/- 10 seconds, as checked against my WWVB watch). The correct > time on birth and death certificates is important, but I was not aware of > how important until I saw a posting from Prof. David Mills on > comp.protocols.time.ntp in which he said that UT1 (not UTC) is the legal > standard for death certificates. My reaction was that this is fascinating > if true, but even if it is (I couldn't find any documentation of this), I > would have to wonder how DUT1 becomes an issue if the tolerance is (as > currently) less than one second? > > Does anyone have any firshand knowledge of forensic medical issues related > to DUT1? The implications of removing the 0.9s limit are clear if Prof. > Mills is correct, but my impression was that time-of-day need only be > precise to within one minute for birth and death certificates. > > > Brian Garrett I'd be interested to hear how one measures the leading edge of the human life to death transition pulse with a precision that makes the UT1 vs. UTC question even relevant. /tvb
Re: pedagogically barren?
- Original Message - From: "Markus Kuhn" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Thursday, June 05, 2003 2:33 AM Subject: Re: [LEAPSECS] pedagogically barren? > "Seeds, Glen" wrote on 2003-06-04 15:00 UTC: > > It's also true that changing to SI units for weight and volume is a lot more > > technically tractable than for length. Public opposition would still be a > > big barrier, though. > > That's what the UK have done. The imperial units of weight and volume > are not legally recognized any more in Britain (only pints are still > permitted for drinks volume), whereas inch/yard/mile continue to be > legally recognized for length and speed. > > To bring the topic closer back to the scope of this mailing list: > > One international standard related to time keeping that I would like to > advertise for is the international standard numeric date and time > notation (ISO 8601), i.e. 2002-08-15 and 14:14:57. > > Whereas both the modern 23:59:59 and the old fashioned 11:59:59 p.m. are > equally widely used in Britain, the modern notation seems to be mostly unknown > in the US outside the military and scientific communities (and the US > military seem to drop the colon as in "1800" and say strange things like > "eighteen hundred hours" instead of "eighteen o'clock"). The uniform > modern 00:00 ... 23:59 notation is now commonly used in Britain for > almost any publically displayed timetable (bus, trains, cinemas, > airports, etc.), and on the Continent they haven't used anything else to > write times for many decades. > A propos of both the topic and the discussion of notation, I've observed that in the U.S., hospitals (where 24-hour notation, or "military time" as civilians inevitably call it) are one of the few businesses where wall clocks are nearly always set to the correct time (within+/- one minute, and often within +/- 10 seconds, as checked against my WWVB watch). The correct time on birth and death certificates is important, but I was not aware of how important until I saw a posting from Prof. David Mills on comp.protocols.time.ntp in which he said that UT1 (not UTC) is the legal standard for death certificates. My reaction was that this is fascinating if true, but even if it is (I couldn't find any documentation of this), I would have to wonder how DUT1 becomes an issue if the tolerance is (as currently) less than one second? Does anyone have any firshand knowledge of forensic medical issues related to DUT1? The implications of removing the 0.9s limit are clear if Prof. Mills is correct, but my impression was that time-of-day need only be precise to within one minute for birth and death certificates. Brian Garrett
Re: pedagogically barren?
Markus Kuhn scripsit: > (and the US > military seem to drop the colon as in "1800" and say strange things like > "eighteen hundred hours" instead of "eighteen o'clock"). They say "klicks" for "kilometers", too. > I really wonder, why the modern notation doesn't > catch on in the US, where even air travel tickets still use the awkward > notation (and solve the ambiguity problem by never scheduling any event > exactly on noon or midnight). You underestimate the tendency of Americans to think that the way they do it is the way God intended (*and* to consider that of paramount importance). -- Some people open all the Windows; John Cowan wise wives welcome the spring [EMAIL PROTECTED] by moving the Unix. http://www.reutershealth.com --ad for Unix Book Units (U.K.) http://www.ccil.org/~cowan (see http://cm.bell-labs.com/cm/cs/who/dmr/unix3image.gif)
Re: pedagogically barren?
-- But that, he realized, was a foolishJohn Cowan thought; as no one knew better than he [EMAIL PROTECTED] that the Wall had no other side.http://www.ccil.org/~cowan --Arthur C. Clarke, "The Wall of Darkness"
Re: pedagogically barren?
Peter Bunclark wrote: On Wed, 4 Jun 2003, William Thompson wrote: Markus Kuhn wrote: (stuff deleted) While the international inch is indeed linked to the meter by a reasonably round factor, and even shows up indirectly in a number of ISO standards (e.g., inch-based threads and pipes), this can clearly not be said for the US pound and the US gallon and units derived from these, which are still required by US federal law to be present on consumer packages. As long as it remains legal and even required in the US to price goods per gallon or pound (units completely unrelated to the inch!), (rest deleted) According to the NIST website, a gallon is defined as exactly 231 cubic inches. I would say that was a long way from being completely unrelated to the inch. While the pound is unrelated to the inch, it is defined as exactly 0.45359237 kilograms. Neither is a nice round number, but there is a definite relationship. William Thompson Well would you Americans consider stopping calling them English Units? It makes me cringe every time the Mars Climate Observer crash is blamed on `English Units'. We call the British equivalent Imperial Units, implying a definite historical context. And teach our kids SI units. Pete. You didn't hear me calling them English Units. I'm surrounding by too many Brits to do that anymore. Actually, the phrase I like is Flintstone Units, which I think I first heard on this mailing list. :-) William Thompson
Re: pedagogically barren?
> > I'd be interested to hear how one measures the > leading edge of the human life to death transition > pulse with a precision that makes the UT1 vs. > UTC question even relevant. > A husband has a will leaving everything to his wife, or if she dies first, to their children. The wife has a will leaving everything to her secret lover. They are together in a car crash, and are put on life-support systems including heart monitors. They both, sadly, die at around the same time; both have a last-recorded heartbeat. Pete.
Re: pedagogically barren?
"Seeds, Glen" wrote on 2003-06-04 15:00 UTC: > It's also true that changing to SI units for weight and volume is a lot more > technically tractable than for length. Public opposition would still be a > big barrier, though. That's what the UK have done. The imperial units of weight and volume are not legally recognized any more in Britain (only pints are still permitted for drinks volume), whereas inch/yard/mile continue to be legally recognized for length and speed. To bring the topic closer back to the scope of this mailing list: One international standard related to time keeping that I would like to advertise for is the international standard numeric date and time notation (ISO 8601), i.e. 2002-08-15 and 14:14:57. Whereas both the modern 23:59:59 and the old fashioned 11:59:59 p.m. are equally widely used in Britain, the modern notation seems to be mostly unknown in the US outside the military and scientific communities (and the US military seem to drop the colon as in "1800" and say strange things like "eighteen hundred hours" instead of "eighteen o'clock"). The uniform modern 00:00 ... 23:59 notation is now commonly used in Britain for almost any publically displayed timetable (bus, trains, cinemas, airports, etc.), and on the Continent they haven't used anything else to write times for many decades. The modern notation is not only shorter and much easier to do mental arithmetic on, it also provides an unambiguous distinction between midnight at the start of day (00:00), noon (12:00) and midnight at the end of day (24:00), whereas the meanings of "12:00 a.m." and "12:00 p.m." are rather ambiguous. I really wonder, why the modern notation doesn't catch on in the US, where even air travel tickets still use the awkward notation (and solve the ambiguity problem by never scheduling any event exactly on noon or midnight). More information on ISO 8601: http://www.cl.cam.ac.uk/~mgk25/iso-time.html Markus -- Markus Kuhn, Computer Lab, Univ of Cambridge, GB http://www.cl.cam.ac.uk/~mgk25/ | __oo_O..O_oo__
Re: pedagogically barren?
Title: RE: [LEAPSECS] pedagogically barren? The "modern" (formally, "24-hour") notation is as common as the 12-hour form in Quebec and France. That's probably the worst possible situation, as you never know what time "9" means. (Quebec is a little better, as the written form 9h00 always means 9AM ). Actually, date is much worse than time, notation-wise, as there are 3 common interpretations for 01/02/03 (010203 in compressed form): YYMMDD: 2001 Feb 3 (monotonic, sorts correctly, ISO standard) DDMMYY: 1 Feb 2003 (monotonic, but sorts incorrectly) MMDDYY: Jan 2 2003 (mixed) The most perverse of these is MMDDYY, which is the norm in the US. (The common US date-month form is MMYY.) All of this is still off-topic for this forum, though. /glen -Original Message- From: Markus Kuhn [mailto:[EMAIL PROTECTED]] Sent: June 5, 2003 5:33 AM To: [EMAIL PROTECTED] Subject: Re: [LEAPSECS] pedagogically barren? "Seeds, Glen" wrote on 2003-06-04 15:00 UTC: > It's also true that changing to SI units for weight and volume is a lot more > technically tractable than for length. Public opposition would still be a > big barrier, though. That's what the UK have done. The imperial units of weight and volume are not legally recognized any more in Britain (only pints are still permitted for drinks volume), whereas inch/yard/mile continue to be legally recognized for length and speed. To bring the topic closer back to the scope of this mailing list: One international standard related to time keeping that I would like to advertise for is the international standard numeric date and time notation (ISO 8601), i.e. 2002-08-15 and 14:14:57. Whereas both the modern 23:59:59 and the old fashioned 11:59:59 p.m. are equally widely used in Britain, the modern notation seems to be mostly unknown in the US outside the military and scientific communities (and the US military seem to drop the colon as in "1800" and say strange things like "eighteen hundred hours" instead of "eighteen o'clock"). The uniform modern 00:00 ... 23:59 notation is now commonly used in Britain for almost any publically displayed timetable (bus, trains, cinemas, airports, etc.), and on the Continent they haven't used anything else to write times for many decades. The modern notation is not only shorter and much easier to do mental arithmetic on, it also provides an unambiguous distinction between midnight at the start of day (00:00), noon (12:00) and midnight at the end of day (24:00), whereas the meanings of "12:00 a.m." and "12:00 p.m." are rather ambiguous. I really wonder, why the modern notation doesn't catch on in the US, where even air travel tickets still use the awkward notation (and solve the ambiguity problem by never scheduling any event exactly on noon or midnight). More information on ISO 8601: http://www.cl.cam.ac.uk/~mgk25/iso-time.html Markus -- Markus Kuhn, Computer Lab, Univ of Cambridge, GB http://www.cl.cam.ac.uk/~mgk25/ | __oo_O..O_oo__ This message may contain privileged and/or confidential information. If you have received this e-mail in error or are not the intended recipient, you may not use, copy, disseminate or distribute it; do not open any attachments, delete it immediately from your system and notify the sender promptly by e-mail that you have done so. Thank you.
Re: pedagogically barren?
Peter Bunclark scripsit: > Well would you Americans consider stopping calling them English Units? > It makes me cringe every time the Mars Climate Observer crash is blamed on > `English Units'. You'd probably cringe if you went to an American restaurant for breakfast and heard the waiter ask the cook for "two toasted English". :-) > We call the British equivalent Imperial Units, implying > a definite historical context. Their proper name (in U.S. government publications and such) is "U.S. customary units". See http://www.wikipedia.org/wiki/U.S._customary_units . > And teach our kids SI units. We teach SI units too, but most people forget them fairly quickly. There are also practical problems: "Retrofitting metric sized wallboard on old 16" spaced studs can be significantly difficult." -- All Norstrilians knew what laughter was:John Cowan it was "pleasurable corrigible malfunction".http://www.reutershealth.com --Cordwainer Smith, _Norstrilia_[EMAIL PROTECTED]
Re: pedagogically barren?
On Wed, 4 Jun 2003, William Thompson wrote: > Markus Kuhn wrote: > > (stuff deleted) > > > While the international inch is indeed linked to the meter by a > > reasonably round factor, and even shows up indirectly in a number of ISO > > standards (e.g., inch-based threads and pipes), this can clearly not be > > said for the US pound and the US gallon and units derived from these, > > which are still required by US federal law to be present on consumer > > packages. As long as it remains legal and even required in the US to > > price goods per gallon or pound (units completely unrelated to the inch!), > > (rest deleted) > > According to the NIST website, a gallon is defined as exactly 231 cubic inches. > I would say that was a long way from being completely unrelated to the inch. > > While the pound is unrelated to the inch, it is defined as exactly 0.45359237 > kilograms. > > Neither is a nice round number, but there is a definite relationship. > > William Thompson > Well would you Americans consider stopping calling them English Units? It makes me cringe every time the Mars Climate Observer crash is blamed on `English Units'. We call the British equivalent Imperial Units, implying a definite historical context. And teach our kids SI units. Pete.
Re: pedagogically barren?
Title: RE: [LEAPSECS] pedagogically barren? It's also true that changing to SI units for weight and volume is a lot more technically tractable than for length. Public opposition would still be a big barrier, though. /glen -Original Message- From: William Thompson [mailto:[EMAIL PROTECTED]] Sent: June 4, 2003 10:35 AM To: [EMAIL PROTECTED] Subject: Re: [LEAPSECS] pedagogically barren? Markus Kuhn wrote: (stuff deleted) > While the international inch is indeed linked to the meter by a > reasonably round factor, and even shows up indirectly in a number of ISO > standards (e.g., inch-based threads and pipes), this can clearly not be > said for the US pound and the US gallon and units derived from these, > which are still required by US federal law to be present on consumer > packages. As long as it remains legal and even required in the US to > price goods per gallon or pound (units completely unrelated to the inch!), (rest deleted) According to the NIST website, a gallon is defined as exactly 231 cubic inches. I would say that was a long way from being completely unrelated to the inch. While the pound is unrelated to the inch, it is defined as exactly 0.45359237 kilograms. Neither is a nice round number, but there is a definite relationship. William Thompson This message may contain privileged and/or confidential information. If you have received this e-mail in error or are not the intended recipient, you may not use, copy, disseminate or distribute it; do not open any attachments, delete it immediately from your system and notify the sender promptly by e-mail that you have done so. Thank you.
Re: pedagogically barren?
Markus Kuhn wrote: (stuff deleted) While the international inch is indeed linked to the meter by a reasonably round factor, and even shows up indirectly in a number of ISO standards (e.g., inch-based threads and pipes), this can clearly not be said for the US pound and the US gallon and units derived from these, which are still required by US federal law to be present on consumer packages. As long as it remains legal and even required in the US to price goods per gallon or pound (units completely unrelated to the inch!), (rest deleted) According to the NIST website, a gallon is defined as exactly 231 cubic inches. I would say that was a long way from being completely unrelated to the inch. While the pound is unrelated to the inch, it is defined as exactly 0.45359237 kilograms. Neither is a nice round number, but there is a definite relationship. William Thompson
Re: pedagogically barren?
Steve Allen wrote on 2003-06-03 20:41 UTC: > My point was that I believe the current list of offered solutions are > not wild enough. If the SRG had clout I would expect to see it > persuading the Galileo system to adopt TI = UTC at the time of launch, > and then I would expect to see them persuading the GPS maintainers to > switch GPS time to match that Galileo TI as a part of the next GPS W1K > rollover. Or I would expect to see them convincing Galileo to adopt > GPS time. Otherwise I would like them to be explaining why these are > not feasible. It was my understanding that some of the proposals implied that the long-term goal would be that all satellite navigation systems should eventually aim at approximating TI as close as feasible with one of the time scales they provide. > If only PowerPoint presentations are posted in the absence of detailed > written arguments and references to published discussions then the > colloquium is pedagogically and archivally barren. Nobody who was not > there can benefit from it. I asked Ron Beard, and he said that there were no plans for written post-proceedings of this meeting. I personally would have liked very much to end up with a written book of everything that was presented and discussed. > This is especially so if it means their garden sundials > will diverge and their descendants will be handed a problem to solve. Sundials diverge anyway thanks to the Equation of Time, and are shipped with compenstation tables. I guess it could be argued that the move from UTC to TI would merely add another term to the Equation of Time, if you accept that most sundials are difficult to read more precisely than a few minutes and that within that tolerance, UT1 should be predictable for a couple of decades, if not centuries. > > Just look at the sorry state of the use of SI > > units in United States legislation to get the idea. > We do use SI units. While the international inch is indeed linked to the meter by a reasonably round factor, and even shows up indirectly in a number of ISO standards (e.g., inch-based threads and pipes), this can clearly not be said for the US pound and the US gallon and units derived from these, which are still required by US federal law to be present on consumer packages. As long as it remains legal and even required in the US to price goods per gallon or pound (units completely unrelated to the inch!), and US congress continues to fail following its constitutional duty of defining and enforcing a proper system of measurements for trade, the use of SI units in the US must unfortunately, in my personal opinion, be described as a rather sorry state. I understand that the inch is here to stay for a long time because of established precision product standards, but this is not the case for the US units of volume, weight, mass and temperature, which could be abandoned trivially over night if there were just a little bit of good will with regard to international standardization. (I'm talking about commercial, not scientific practice.) Markus -- Markus Kuhn, Computer Lab, Univ of Cambridge, GB http://www.cl.cam.ac.uk/~mgk25/ | __oo_O..O_oo__
