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    <div class="moz-cite-prefix">Ed,<br>
      <br>
      We may well be compelled to apply for the URN but in defense of
      not doing so let me say:<br>
      <br>
      1. The true purpose of a URN (in my opinion) is to reference
      something that should already be known to the reader. In STEP we
      already know what the definition of an inch is - it has been the
      same in every P21 file for the last 20 years.<br>
      2. Why would someone outside of STEP want to access the STEP
      definition of inch as encoded in a P21 file (and stored at the
      Part 41 URL given earlier in the e-mail trail)? If no one external
      to STEP is going to reference why register?<br>
      <br>
      The key reason for using <urn:step:inch> is that it is a
      familiar notation more or less. Most people know that a URN is the
      alternative to a URL and that it is to be used when something is
      already known . Calling it a stepid as in <stepid:step:inch>
      would not have this advantage.<br>
      <br>
      Thanks for sticking with me on this.<br>
      <br>
      Martin<br>
      <br>
      PS Let me try to prevent messages about being STEP centric by
      reminding us all that I am also proposing/suggesting the use of
      <urn:ifc:inch> and <urn:iso15926:inch><br>
      <br>
      <br>
      On 6/11/2014 4:51 PM, Barkmeyer, Edward J wrote:<br>
    </div>
    <blockquote
cite="mid:a23609b506984bff82dcbc23c6726c96@BN1PR09MB107.namprd09.prod.outlook.com"
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      <div class="WordSection1">
        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Martin,<o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Well,
            if you take that view, why use ‘urn’ at all?  Why not call
            it ‘stepid:’?  If you are not going to abide by the
            standard, why use the standard prefix?<o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">And
            if there is no registry for these names, what happens when
            some other organization chooses to use urn:step for their
            names?  Of course, there will never be any company that uses
            STEP and the Step.org estate planning people, but the
            possibilities for the ‘step’ acronym are hardly restricted
            to SC4.  That is why we have registries – to insure that
            symbols are unique.
            <o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">The
            Linked Open Data people may be wrong about the future, but I
            can guarantee that the closed world of standards in SC4 is
            already a thing of the past.  Integrating data across
            multiple models and sources is the future of industrial IT. 
            If it weren’t, your Part 21 project would not be.  With a
            little effort, we can avoid creating a pit that someone will
            fall into 2 years from now.<o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">-Ed<o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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          0in 0in 4.0pt">
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              1.0pt;padding:3.0pt 0in 0in 0in">
              <p class="MsoNormal"
                style="text-autospace:ideograph-numeric ideograph-other"><b><span
style="font-family:"Tahoma","sans-serif";color:windowtext">From:</span></b><span
style="font-family:"Tahoma","sans-serif";color:windowtext">
                  Martin Hardwick [<a class="moz-txt-link-freetext" href="mailto:hardwick@steptools.com">mailto:hardwick@steptools.com</a>]
                  <br>
                  <b>Sent:</b> Wednesday, June 11, 2014 2:43 PM<br>
                  <b>To:</b> Barkmeyer, Edward J; Thomas.r.thurman<br>
                  <b>Cc:</b> Thomas Liebich; wg11; Palmer, Mark E. Mr.;
                  <a class="moz-txt-link-abbreviated" href="mailto:magne.valen.sendstad@gmail.com">magne.valen.sendstad@gmail.com</a><br>
                  <b>Subject:</b> Re: [wg11] units of measure, from
                  Minutes of Part 21 E3 DIS testing telecon on June 5,
                  2914<o:p></o:p></span></p>
            </div>
          </div>
          <p class="MsoNormal"><o:p> </o:p></p>
          <div>
            <p class="MsoNormal"><br>
              Why does a URN have to be registered?<br>
              <br>
              If one of our documents says <urn:step:inch><u> in a
                STEP model</u> means an inch as defined at
              <span
style="font-size:11.0pt;font-family:"Calibri","sans-serif""><a
                  moz-do-not-send="true"
href="http://standards.iso.org/iso/10303/tech/reference_data/-41/units.stp#INCH"><http://standards.iso.org/iso/10303/tech/reference_data/-41/units.stp#INCH></a></span>;
              is anybody going to complain, and if so to whom?<br>
              <br>
              Martin<br>
              <br>
              On 6/11/2014 1:26 PM, Barkmeyer, Edward J wrote:<o:p></o:p></p>
          </div>
          <blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
            <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Fine. 
                Then someone has to do the ICANN registration process
                for urn:step!  And since I assisted Joanna Goodwin and
                Holger Apel with that rigamarole producing RFC 5141, I
                can tell you they didn’t make it easy.  It is NOT like
                paying $100 for a domain name.</span><o:p></o:p></p>
            <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
            <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I
                undertook that for SC4, so that
                urn:iso:std:iso:10303:term:xxx would be automatically
                valid, and so that SC4 could define URNs beginning
                urn:iso:std:iso:10303:tech and other such identifiers. 
                If you want urn:step, you should have stepped up in
                2004-5 when we did that (but you probably would not have
                had support from JTC1 and TC68 and TC154).</span><o:p></o:p></p>
            <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
            <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I
                don’t really care whether you use URNs or not.  Sir Tim
                got his way and denatured http: and made the whole URN
                effort largely useless.  (It was neither the first nor
                last waste of my time in standards land.)  What you do
                have to realize is that there is a formal procedure for
                creating URIs of either kind, and if you elect not to
                use what has already been done, you get to put the
                resources into repeating the procedure.</span><o:p></o:p></p>
            <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
            <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">STEP
                as a whole is a sow’s ear, but it works and using it is
                a lot cheaper than trying to roll your own silk purse.</span><o:p></o:p></p>
            <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
            <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">-Ed</span><o:p></o:p></p>
            <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
            <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
            <div style="border:none;border-left:solid blue
              1.5pt;padding:0in 0in 0in 4.0pt">
              <div>
                <div style="border:none;border-top:solid #B5C4DF
                  1.0pt;padding:3.0pt 0in 0in 0in">
                  <p class="MsoNormal"
                    style="text-autospace:ideograph-other"><b><span
style="font-family:"Tahoma","sans-serif";color:windowtext">From:</span></b><span
style="font-family:"Tahoma","sans-serif";color:windowtext">
                      Martin Hardwick [<a moz-do-not-send="true"
                        href="mailto:hardwick@steptools.com">mailto:hardwick@steptools.com</a>]
                      <br>
                      <b>Sent:</b> Wednesday, June 11, 2014 12:56 PM<br>
                      <b>To:</b> Barkmeyer, Edward J; Thomas.r.thurman<br>
                      <b>Cc:</b> Thomas Liebich; wg11; Palmer, Mark E.
                      Mr.; <a moz-do-not-send="true"
                        href="mailto:magne.valen.sendstad@gmail.com">
                        magne.valen.sendstad@gmail.com</a><br>
                      <b>Subject:</b> Re: [wg11] units of measure, from
                      Minutes of Part 21 E3 DIS testing telecon on June
                      5, 2914</span><o:p></o:p></p>
                </div>
              </div>
              <p class="MsoNormal"> <o:p></o:p></p>
              <div>
                <p class="MsoNormal">On 6/11/2014 12:39 PM, Barkmeyer,
                  Edward J wrote:<o:p></o:p></p>
              </div>
              <blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
                <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Martin,</span><o:p></o:p></p>
                <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
                <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Why
                    is: 
                  </span><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif""><a
                      moz-do-not-send="true"
href="http://standards.iso.org/iso/10303/tech/reference_data/-41/units.stp#INCH"><http://standards.iso.org/iso/10303/tech/reference_data/-41/units.stp#INCH></a></span>;<o:p></o:p></p>
                <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif"">less
                    “convoluted” than:</span> 
                  <span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">   
                    urn:iso:std:iso:31:term:metre</span><o:p></o:p></p>
                <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">???</span><o:p></o:p></p>
              </blockquote>
              <p class="MsoNormal"
                style="text-autospace:ideograph-other"><span
                  style="font-size:12.0pt">You tell me. I want to use
                  <urn:step:inch><br>
                  <br>
                  As implementors we have found that less typing means
                  less scope for mistakes. <br>
                  <br>
                  If there is going to have to be lots of typing then </span><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif""><a
                    moz-do-not-send="true"
href="http://standards.iso.org/iso/10303/tech/reference_data/-41/units.stp#INCH"><http://standards.iso.org/iso/10303/tech/reference_data/-41/units.stp#INCH></a></span><span
                  style="font-size:12.0pt">; is better than </span><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">urn:iso:std:iso:31:term:metre 
                </span><span style="font-size:12.0pt">because there are
                  lots of ways to check for badly type URL's and hardly
                  any to check a badly typed URN.<br>
                  <br>
                  Your URN requires me to remember:<br>
                  1. Type iso twice<br>
                  2. The standard number is 31<br>
                  3. The concept being defined is a term<br>
                  <br>
                  As an implementor I can do all this. Just look at what
                  we did for units in Part 21 Edition 1 and 2.
                  <br>
                  <br>
                  Martin<br>
                  <br>
                  <br>
                </span><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">The
                  http: form just uses a different ISO CS directive for
                  formulating IRIs, which is “jealously guarded” by ISO
                  CS in exactly the same way!</span><span
                  style="font-size:12.0pt">
                </span><o:p></o:p></p>
              <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">In
                  both cases, ISOCS specifies what everything up to the
                  “tech” part must be, and the SC gets to define what
                  follows.</span><o:p></o:p></p>
              <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
              <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">The
                  point of the ISO URNs of the form above is that MERELY
                  by having the term defined in an existing ISO
                  standard, there IS a standard IRI for the term.  And
                  if multiple standards define “metre”, then it is very
                  important that you know WHICH meaning is intended by
                  the reference! 
                </span><o:p></o:p></p>
              <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
              <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Why
                  would it be better for ISO 10303 to define what it
                  means by “inch” than what some industry reference
                  standard defines “inch” to mean?  Do I have to find a
                  different IRI if I am using an ASTM standard?  or an
                  API standard?  </span><o:p></o:p></p>
              <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
              <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">The
                  problem is to get a reference standard that defines
                  the “conversion based units” (English measure, et al.)
                  that we want to be able to use, and then to use one of
                  the ISO-specified forms for creating the corresponding
                  IRI, whether it begins http: or urn:.  Enabling such
                  things is exactly why ISOCS went to the trouble of
                  registering the URN and URL forms and publishing the
                  corresponding directives.  And if the reference
                  standard is not an ISO standard, then we will be bound
                  by whatever URI syntax that particular SDO set up. 
                  So, if urn:ifc, or
                  <a moz-do-not-send="true" href="http://ifc.org/">http://ifc.org/</a>,
                  is an ICANN registered prefix, and the IFC defines
                  urn:ifc:inch, or whatever “convoluted” form IFC
                  decides on, we could use that and be done.</span><o:p></o:p></p>
              <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
              <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">The
                  point of all this is that the references for
                  constructing IRIs are already in place.  What is
                  necessary is the *<b>standard</b>* that defines the
                  terms you want to use, so that the IRI that refers to
                  that term in that standard can be employed.  Stop
                  worrying about the IRIs and figure out where/what the
                  reference standard is to be.  By way of assisting in
                  this,  I have put in a request to a NIST SI/BIPM
                  person to identify an appropriate specification for
                  English measures, but I have not yet received a
                  response.</span><o:p></o:p></p>
              <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
              <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">-Ed</span><o:p></o:p></p>
              <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
              <div style="border:none;border-left:solid blue
                1.5pt;padding:0in 0in 0in 4.0pt">
                <div>
                  <div style="border:none;border-top:solid #B5C4DF
                    1.0pt;padding:3.0pt 0in 0in 0in">
                    <p class="MsoNormal"
                      style="text-autospace:ideograph-other"><b><span
style="font-family:"Tahoma","sans-serif";color:windowtext">From:</span></b><span
style="font-family:"Tahoma","sans-serif";color:windowtext">
                        Martin Hardwick [<a moz-do-not-send="true"
                          href="mailto:hardwick@steptools.com">mailto:hardwick@steptools.com</a>]
                        <br>
                        <b>Sent:</b> Wednesday, June 11, 2014 6:35 AM<br>
                        <b>To:</b> Thomas.r.thurman<br>
                        <b>Cc:</b> Barkmeyer, Edward J; Thomas Liebich;
                        wg11; Palmer, Mark E. Mr.; <a
                          moz-do-not-send="true"
                          href="mailto:magne.valen.sendstad@gmail.com">
                          magne.valen.sendstad@gmail.com</a><br>
                        <b>Subject:</b> Re: [wg11] units of measure,
                        from Minutes of Part 21 E3 DIS testing telecon
                        on June 5, 2914</span><o:p></o:p></p>
                  </div>
                </div>
                <p class="MsoNormal"> <o:p></o:p></p>
                <div>
                  <p class="MsoNormal"><br>
                    Again my purpose is to investigate how P21 e3 might
                    help. The most we can venture is to produce some
                    recommendations and examples.<br>
                    <br>
                    My summary of the previous e-mails is that the ISO
                    namespace <urn:iso> is jealously guarded to
                    keep the peace between the committees. We are never
                    going to be able to use it to make something easy
                    for the implementors.<br>
                    <br>
                    However, before giving up on URN's I would like to
                    get opinion on the following: Can we define our own
                    namespaces?<br>
                    <br>
                    We might do this for each standard, or at the level
                    of SC4.<br>
                    <br>
                    For example, if we decide to use URNs to define
                    units for STEP then<br>
                    1. The URN for inch might be <urn:step:inch>;<br>
                    2. The URN would be mapped by appropriate wording in
                    the appropriate place to the URL
                    <br>
                    <a moz-do-not-send="true"
href="http://standards.iso.org/iso/10303/tech/reference_data/-41/units.stp#INCH"><http://standards.iso.org/iso/10303/tech/reference_data/-41/units.stp#INCH></a>;<br>
                    3. The URN would only have to have meaning for a
                    STEP model.<br>
                    <br>
                    We would then do the same for ifc
                    <urn:ifc:inch> and iso15926
                    <urn:iso15926:inch> etc.
                    <br>
                    <br>
                    The appropriate wording in #2 could be words in the
                    standards document, or it could be a rule in the
                    standards document telling you where to find a
                    server with the permitted URNs.
                    <br>
                    <br>
                    Martin Hardwick<br>
                    Team Leader ISO STEP-Manufacturing<br>
                    <br>
                    <br>
                    <br>
                    On 6/10/2014 8:15 PM, Thomas.r.thurman wrote:<o:p></o:p></p>
                </div>
                <blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
                  <div>
                    <p class="MsoNormal">The purpose behind the units
                      thing in P21 ed3 EXAMPLEs is to help move things
                      forward,<o:p></o:p></p>
                  </div>
                  <div>
                    <p class="MsoNormal">as opposed to just having
                      examples in p41.<o:p></o:p></p>
                  </div>
                  <div>
                    <p class="MsoNormal">The BIPM has made general
                      quantities and units document publicly available,
                      but ISO 80000-x <o:p></o:p></p>
                  </div>
                  <div>
                    <p class="MsoNormal">is still behind a paywall which
                      means I have to buy a copy of it to understand
                      what a term means.<o:p></o:p></p>
                  </div>
                  <div>
                    <p class="MsoNormal"> <o:p></o:p></p>
                  </div>
                  <div>
                    <p class="MsoNormal">What is the <b><i><u>business</u></i></b>
                      process for moving forward?<o:p></o:p></p>
                  </div>
                  <div>
                    <p class="MsoNormal">Regards,<o:p></o:p></p>
                  </div>
                  <div>
                    <p class="MsoNormal">Tom<br>
                      Sent from my iPad<o:p></o:p></p>
                  </div>
                  <div>
                    <p class="MsoNormal" style="margin-bottom:12.0pt"><br>
                      On Jun 10, 2014, at 4:11 PM, Martin Hardwick <<a
                        moz-do-not-send="true"
                        href="mailto:hardwick@steptools.com">hardwick@steptools.com</a>>
                      wrote:<o:p></o:p></p>
                  </div>
                  <blockquote
                    style="margin-top:5.0pt;margin-bottom:5.0pt">
                    <div>
                      <div>
                        <p class="MsoNormal"><br>
                          Hi Ed,<br>
                          <br>
                          Thanks for these comments and before anyone
                          gets the wrong idea let me state emphatically
                          that Part Edition 3 is NOT, NOT, NOT planning
                          to define any units. We are only looking at
                          what might become possible if URI's are
                          allowed in the Part 21 standard.<br>
                          <br>
                          One option for the relevant committees is to
                          keep the status quo and demand that all units
                          are defined from first principles as is
                          currently the case in all the STEP Application
                          Protocols. Thus every time an inch is used it
                          must be defined as being 25.4 millimeters. 
                          (As an aside I wonder what would happen if a
                          file defined an inch as 25.3 millimeters.
                          Would the software notice? Would it follow
                          through and convert all the units by the given
                          formula. Would the result be a correct model?
                          What about the accuracy constraints? Has STEP
                          been consistent about applying the conversion
                          across all the cases?)<br>
                          <br>
                          The second option is to use URL's. This is the
                          option that is being most actively
                          investigated by the P21 e3 group. This option
                          is currently running into several small issues
                          with respect to conversion based units. As I
                          understand it the issues are derived from
                          problems in the PLIB expression schema, but on
                          a more personal level I have always thought it
                          crazy to encode expressions in the PLIB
                          expression schema.<br>
                          <br>
                          This started me thinking about the URN option
                          in more detail. As I understand it a URN is
                          used when the systems are expected to "know"
                          the definition.<br>
                          <br>
                          Hence I wonder why we cannot define<br>
                          <br>
                          <urn:iso:inch><br>
                          <br>
                          In the context of an AP242 file this would
                          mean the current definition only with the
                          conversion GUARANTEED to be 25.4. For an OWL
                          system it would be whatever OWL systems expect
                          and so on. It is a URN so nothing has to be at
                          the other end of the definition, but something
                          could be so STEP could say this URN is defined
                          by the definitions at the following URL (which
                          can then be as complex as any standards
                          organization can imagine).<br>
                          <br>
                          I really wonder what the advantage of a
                          convoluted URN such as <span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">urn:iso:std:iso:31:term:metre</span> 
                          might be. Does this mean that different
                          standards groups are going to define different
                          metres?<br>
                          <br>
                          There is also the practical issue for system
                          implementors of what to do if someone types
                          the URN's slightly wrong which increases as
                          the URN gets longer.
                          <br>
                          <br>
                          As an implementor <urn:iso:inch> seems
                          just about acceptable because there is very
                          small possibility that we will want to have
                          two definitions for inch in STEP files - one
                          defined by ISO and another defined by Martians
                          <urn:mars:inch>. A more practical
                          example might be the definition of pint which
                          is different between the UK
                          <urn:iso:uk:pint> and the USA
                          <urn:iso:usa:pint>. I can see that ISO
                          might shy away from making this kind of
                          distinction, but in this case can STEP should
                          define its own name space
                          <urn:step:inch> for its own STEP files.<br>
                          <br>
                          Thanks for your attention. If we are going to
                          have to write URN's that are as long and
                          convoluted as the URL's then we may as well
                          stick with the URL's, so I am hoping there is
                          a better solution.<br>
                          <br>
                          Martin<br>
                          <br>
                          <br>
                          <br>
                          On 6/10/2014 4:42 PM, Barkmeyer, Edward J
                          wrote:<o:p></o:p></p>
                      </div>
                      <blockquote
                        style="margin-top:5.0pt;margin-bottom:5.0pt">
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Martin,</span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I
                            agree that fuddling with Part 41
                            representations of measurement units that
                            should have reference IRIs is “so 1990s”. 
                            But moving on requires a wider commitment.</span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">urn:iso:
                            ... is a well-defined identifier form, and
                            ISO CS is the registry for it.  See IETF RFC
                            5141. (<a moz-do-not-send="true"
                              href="http://www.rfc-editor.org/info/rfc5141">http://www.rfc-editor.org/info/rfc5141</a>)</span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Some
                            of these units are defined terms in ISO 31,
                            ISO 1000 and ISO 80000.  As a consequence
                            they have a well-defined URN per the RFC.</span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">For
                            example, the URN for ‘metre’ is (I think):</span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">   
                            urn:iso:std:iso:31:term:metre</span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">It
                            is doubtless the case that one of the ISO
                            measurement units standards defines cm/s,
                            but it is unlikely that any defines
                            ‘furlong’ or ‘inches per second’.  That is
                            why Part 41 has the conversion_based_unit
                            construct.</span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">SC4
                            has authority from ISOCS to define ISO URNs
                            by attaching :tech:<whatever> to any
                            (Part of any) SC4 developed standard
                            identifier, with the proviso that these
                            identifiers are, in fact, defined in the
                            technical specification.  It is in fact
                            possible for Part 21 to specify URNs of the
                            form:</span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">  
                            urn:iso:std:iso:10303:tech: xxx</span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">without
                            identifying the Part number.  I suspect that
                            WG12 would consider it inappropriate for
                            Part 21 to contain such specifications,
                            however.</span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Further,
                            there is an issue in WG3 to align ISO
                            15926-4 with ISO 80000 and perhaps to
                            incorporate some elements of NASA QUDT,
                            which is an OWL ontology of every unit NASA
                            has ever dreamed of using, based on a
                            fundamental ontology that mirrors ISO 80000
                            and the International Vocabulary for
                            Measures (VIM).  So, it may be possible that
                            these desired “common units” have the form:</span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> 
urn:iso:std:iso:15926:-4:tech:class:INCHES_PER_SECOND
                          </span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">or
                            something the like.  It is definitely the
                            intent of WG3 that they will have a URI</span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> 
                            <a moz-do-not-send="true"
                              href="http://iso.org/std/iso/15926/-4">http://iso.org/std/iso/15926/-4#</a>
                            INCHES_PER_SECOND</span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">or
                            something the like (and that is only because
                            W3C decided that http: is the universal
                            prefix for IRIs, and no longer denotes a
                            protocol).  But WG3 would really prefer that
                            QUDT was a referenceable standard in its own
                            right, with its own IRI path.</span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">With
                            the above as background, it is important for
                            SC4 to avoid participating in the
                            construction of another cottage industry. 
                            It would be a “good thing” for SC4 to bring
                            its interested parties to a common table and
                            come up with a common solution to this
                            problem for SC4 specifications, instead of
                            one-off conventions for the favorite
                            technology of each Working Group. 
                          </span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">-Ed</span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
                        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
                        <div style="border:none;border-left:solid blue
                          1.5pt;padding:0in 0in 0in 4.0pt">
                          <div>
                            <div style="border:none;border-top:solid
                              #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in">
                              <p class="MsoNormal"
                                style="text-autospace:ideograph-other"><b><span
style="font-family:"Tahoma","sans-serif";color:windowtext">From:</span></b><span
style="font-family:"Tahoma","sans-serif";color:windowtext">
                                  wg11 [<a moz-do-not-send="true"
                                    href="mailto:wg11-bounces@steptools.com">mailto:wg11-bounces@steptools.com</a>]
                                  <b>On Behalf Of </b>Martin Hardwick<br>
                                  <b>Sent:</b> Tuesday, June 10, 2014
                                  10:22 AM<br>
                                  <b>To:</b> Thomas Liebich; wg11<br>
                                  <b>Subject:</b> Re: [wg11] Minutes of
                                  Part 21 E3 DIS testing telecon on June
                                  5, 2914</span><o:p></o:p></p>
                            </div>
                          </div>
                          <p class="MsoNormal"> <o:p></o:p></p>
                          <div>
                            <p class="MsoNormal">Hi Thomas,<br>
                              <br>
                              Thanks for this feedback.<br>
                              <br>
                              I am growing in favor of using a simple
                              URN for all the "famous" (well known
                              units).<br>
                              <br>
                              Hence, we might have in the reference
                              section of a P21 e3 file:<br>
                              <br>
                              #10=<urn:iso:metre>;<br>
                              #20=<urn:iso:inch>;<br>
                              #30=<urn:iso:centigrade>;<br>
                              #40=<urn:iso:Fahrenheit>;<br>
                              #50=<urn:iso:furlong> ;<br>
                              #60=<urn:iso:inches-per-second>;<br>
                              <br>
                              And so on for all the units that the
                              standards want to recognize. There would
                              not need to be any files to define these
                              units (but there could be). Software
                              systems would be expected to "know" them
                              from the URN and that would include
                              knowing how to convert between them. <br>
                              <br>
                              (Without benefit of a conversion based
                              expression - oh my gosh what will happen
                              if there is an apocalypse and the only
                              people left are idiot savant nerds who
                              only know how to follow mathematical
                              expressions and cannot remember any units
                              except the ones stored in the NIST library
                              which was the only building in Washington
                              to survive the catastrophe of course) -
                              Yes I will be made to regret this
                              statement.<br>
                              <br>
                              Martin<br>
                              <br>
                              <br>
                              On 6/10/2014 9:29 AM, Thomas Liebich
                              wrote:<o:p></o:p></p>
                          </div>
                          <blockquote
                            style="margin-top:5.0pt;margin-bottom:5.0pt">
                            <p class="MsoNormal"
                              style="margin-bottom:12.0pt">Dear all,<br>
                              <br>
                              only as a side remark. During our IFC
                              (ISO16739) developments we faced the same
                              issue - a derived unit involving factor
                              and offset cannot be defined with the
                              current conversion_based_unit.<br>
                              <br>
                              So we added a subtype to IFC4, which
                              essentially defines the same, as the
                              proposed extension here for P41.<br>
                              See <a moz-do-not-send="true"
href="http://www.buildingsmart-tech.org/ifc/IFC4/final/html/link/ifcconversionbasedunitwithoffset.htm">http://www.buildingsmart-tech.org/ifc/IFC4/final/html/link/ifcconversionbasedunitwithoffset.htm</a><br>
                              <br>
                              One important consideration: you need to
                              determine, whether to apply the offset
                              before or after applying the factor. We
                              decided to apply it after.<br>
                              <br>
                              hope it gives another insight,<br>
                              <br>
                              regards<br>
                              Thomas<br>
                              <br>
                              -- <o:p></o:p></p>
                            <div>
                              <p class="MsoNormal">Am 08.06.2014 01:46,
                                schrieb thomas thurman:<o:p></o:p></p>
                            </div>
                            <blockquote
                              style="margin-top:5.0pt;margin-bottom:5.0pt">
                              <p class="MsoNormal">Addendum for
                                Fahrenheit discussion. <o:p></o:p></p>
                              <div>
                                <div>
                                  <p class="MsoNormal">Comments on
                                    current approach in part 41 and AP
                                    214:<o:p></o:p></p>
                                  <div>
                                    <div>
                                      <div>
                                        <p class="MsoNormal">1-part 41
                                          is specific that any unit that
                                          is related to a unit specified
                                          in part 41 shall be a
                                          ‘conversion_based_unit’.<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">2-conversion_based_unit
                                          only converts the magnitude
                                          but does not provide an
                                          offset.<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">3-The use
                                          of ISO 13584-20 for such a
                                          simple case is long agreed
                                          overkill; the example in part
                                          41 F 4.4 has EXPRESS<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">errors (<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">a-the
                                          expression_conversion_based_unit
                                          shall be a
                                          conversion_based_unit (see (1)
                                          above.) and<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">b-the
                                          attribute redeclaration in
                                          e.g.,
                                          named_unit_variable.associated_variable_environment
                                          is invalid.).<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">4-AP 242
                                          ed1 did not include a
                                          structure to support
                                          Fahrenheit unit exchange.<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">5-AP214
                                          used a context_dependent_unit
                                          which is invalid (see (1)
                                          above). As noted above this
                                          was NOT promoted to<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">AP 242.<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">6-After
                                          several attempts to discover a
                                          URL,URN for Fahrenheit I gave
                                          up and am proposing that SC4
                                          define its own<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">(NIST has a
                                          guide that includes a
                                          definition of Fahrenheit as a
                                          note (I think) but does not
                                          provide a URN or URL.).<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">(There are
                                          multiple conversion
                                          calculators on the web but I
                                          am not convinced of their
                                          persistence.<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">In any
                                          event use of a conversion
                                          calculator opens up its own
                                          can of worms.)<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal"> <o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">==========proposed
                                          solution:===========<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal"> <o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">add a
                                          subtype of
                                          conversion_based_unit,
                                          conversion_based_unit_with_offset
                                          to provide the offset.<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal"> <o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">=========current:============<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal"> <o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal"><span
                                            style="font-size:13.5pt;font-family:"Times","serif"">A <b>conversion_based_unit</b> is
                                            a type of </span><a
                                            moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresources%5Cmeasure_schema%5Cmeasure_schema.htm#measure_schema.named_unit"><b><span
style="font-size:13.5pt;font-family:"Times","serif"">named_unit</span></b></a><span
style="font-size:13.5pt;font-family:"Times","serif""> that

                                            defines a unit on the basis
                                            of a </span><a
                                            moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresources%5Cmeasure_schema%5Cmeasure_schema.htm#measure_schema.measure_with_unit"><b><span
style="font-size:13.5pt;font-family:"Times","serif"">measure_with_unit</span></b></a><span
style="font-size:13.5pt;font-family:"Times","serif"">.</span>
                                          <o:p></o:p></p>
                                        <p class="note"><a
                                            moz-do-not-send="true"
                                            name="note_"><span
                                              style="font-family:"Times","serif"">NOTE </span></a><span
style="font-family:"Times","serif"">   The <a
                                              moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresources%5Cmeasure_schema%5Cmeasure_schema.htm#measure_schema.measure_with_unit.value_component"><b>value_component</b></a> attribute

                                            of the <a
                                              moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresources%5Cmeasure_schema%5Cmeasure_schema.htm#measure_schema.measure_with_unit"><b>measure_with_unit</b></a> defines
                                            the conversion factor.</span><o:p></o:p></p>
                                        <p class="example"><a
                                            moz-do-not-send="true"
                                            name="example_"><span
                                              style="font-family:"Times","serif"">EXAMPLE   
                                              An inch is a <b>conversion_based_unit</b>.
                                              It is from the Imperial
                                              system, its name is
                                              "inch", and it can be
                                              related to the </span></a><a
                                            moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresources%5Cmeasure_schema%5Cmeasure_schema.htm#measure_schema.si_unit"><b><span
style="font-family:"Times","serif"">si_unit</span></b></a><span
style="font-family:"Times","serif"">, millimetre,
                                            through a </span><a
                                            moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresources%5Cmeasure_schema%5Cmeasure_schema.htm#measure_schema.measure_with_unit"><b><span
style="font-family:"Times","serif"">measure_with_unit</span></b></a><span
style="font-family:"Times","serif""> whose value is
                                            25.4 millimetre. A foot is
                                            also a <b>conversion_based_unit</b>.
                                            It is from the Imperial
                                            system, its name is "foot",
                                            and it can be related to an </span><a
                                            moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresources%5Cmeasure_schema%5Cmeasure_schema.htm#measure_schema.si_unit"><b><span
style="font-family:"Times","serif"">si_unit</span></b></a><span
style="font-family:"Times","serif"">, millimetre,
                                            either directly or through
                                            the unit called "inch".</span><o:p></o:p></p>
                                        <div>
                                          <p class="MsoNormal"><u><span
style="font-size:13.5pt;font-family:"Times","serif"">EXPRESS
                                                specification:</span></u><o:p></o:p></p>
                                        </div>
                                        <p><code><span
                                              style="font-size:10.0pt">*)</span></code><span
                                            style="font-size:10.0pt;font-family:"Courier
                                            New","serif""><br>
                                            <code>ENTITY
                                              conversion_based_unit</code><br>
                                            <code>  SUBTYPE OF (</code></span><a
                                            moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresource_docs%5Cfundamentals_of_product_description_and_support%5Csys%5C18_schema.htm#measure_schema.named_unit"><span
                                              style="font-size:10.0pt;font-family:"Courier
New","serif"">named_unit</span></a><code><span
                                              style="font-size:10.0pt">);</span></code><span
                                            style="font-size:10.0pt;font-family:"Courier
                                            New","serif""><br>
                                            <code>  name : </code></span><a
                                            moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresource_docs%5Cfundamentals_of_product_description_and_support%5Csys%5C25_schema.htm#support_resource_schema.label"><span
                                              style="font-size:10.0pt;font-family:"Courier
New","serif"">label</span></a><code><span
                                              style="font-size:10.0pt">;</span></code><span
                                            style="font-size:10.0pt;font-family:"Courier
                                            New","serif""><br>
                                            <code>  conversion_factor : </code></span><a
                                            moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresource_docs%5Cfundamentals_of_product_description_and_support%5Csys%5C18_schema.htm#measure_schema.measure_with_unit"><span
                                              style="font-size:10.0pt;font-family:"Courier
New","serif"">measure_with_unit</span></a><code><span
                                              style="font-size:10.0pt">;</span></code><span
                                            style="font-size:10.0pt;font-family:"Courier
                                            New","serif""><br>
                                            <code>WHERE</code><br>
                                            <code>  WR1:
                                              SELF\named_unit.dimensions
                                              =
derive_dimensional_exponents(conversion_factor\measure_with_unit.unit_component);</code><br>
                                            <code>END_ENTITY;</code><br>
                                            <code>(*</code></span><o:p></o:p></p>
                                        <p><u><span
                                              style="font-size:13.5pt;font-family:"Times","serif"">Attribute
                                              definitions:</span></u><o:p></o:p></p>
                                        <p class="expressdescription"><b><span
style="font-size:13.5pt;font-family:"Times","serif"">name: </span></b><span
style="font-size:13.5pt;font-family:"Times","serif"">the </span><a
                                            moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresources%5Csupport_resource_schema%5Csupport_resource_schema.htm#support_resource_schema.label"><b><span
style="font-size:13.5pt;font-family:"Times","serif"">label</span></b></a><span
style="font-size:13.5pt;font-family:"Times","serif""> by

                                            which the <b>conversion_based_unit</b> is
                                            known.</span><o:p></o:p></p>
                                        <p class="expressdescription"><a
                                            moz-do-not-send="true"
                                            name="measure_schema.conversion_based_unit.con"><b><span
style="font-size:13.5pt;font-family:"Times","serif"">conversion_factor: </span></b></a><span
style="font-size:13.5pt;font-family:"Times","serif"">the </span><a
                                            moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresources%5Cmeasure_schema%5Cmeasure_schema.htm#measure_schema.measure_with_unit"><b><span
style="font-size:13.5pt;font-family:"Times","serif"">measure_with_unit</span></b></a><span
style="font-size:13.5pt;font-family:"Times","serif""> that

                                            specifies the physical
                                            quantity from which the <b>conversion_based_unit</b> is
                                            derived.</span><o:p></o:p></p>
                                        <p><u><span
                                              style="font-size:13.5pt;font-family:"Times","serif"">Formal
                                              propositions:</span></u><o:p></o:p></p>
                                        <p class="expressdescription"><b><span
style="font-size:13.5pt;font-family:"Times","serif"">WR1: </span></b><span
style="font-size:13.5pt;font-family:"Times","serif"">The
                                            dimensional exponents shall
                                            be equal to those from the </span><a
                                            moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresources%5Cmeasure_schema%5Cmeasure_schema.htm#measure_schema.conversion_based_unit.conversion_factor"><b><span
style="font-size:13.5pt;font-family:"Times","serif"">conversion_factor</span></b></a><span
style="font-size:13.5pt;font-family:"Times","serif"">.</span><o:p></o:p></p>
                                        <div>
                                          <p class="MsoNormal"><span
                                              style="font-size:12.0pt"> </span><o:p></o:p></p>
                                        </div>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">=========proposed
                                          addition to part 41=========<o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal"><span
                                            style="font-size:13.5pt;font-family:"Times","serif"">A <b>conversion_based_unit_with_offset</b> is
                                            a type of <b>conversion_based_unit</b> that
                                            includes a scale offset.</span><o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="note"><span
                                            style="font-size:13.5pt;font-family:"Times","serif"">EXAMPLE   
                                            A Fahrenheit is a <b>conversion_based_unit_with_offset</b>.
                                            It is from the Imperial
                                            system, its name is
                                            “fahrenheit", and it can be
                                            related to the <a
                                              moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresources%5Cmeasure_schema%5Cmeasure_schema.htm#measure_schema.si_unit"><b>si_unit</b></a>,
                                            degree Celsius, through a <a
                                              moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresources%5Cmeasure_schema%5Cmeasure_schema.htm#measure_schema.measure_with_unit"><b>measure_with_unit</b></a> whose
                                            value is 1.8 degree Celsius.
                                            The offset is 32 degree
                                            Celsius.</span><o:p></o:p></p>
                                        <p><u><span
                                              style="font-size:13.5pt;font-family:"Times","serif"">EXPRESS
                                              specification:</span></u><o:p></o:p></p>
                                        <p><code><span
                                              style="font-size:10.0pt">*)</span></code><span
                                            style="font-size:10.0pt;font-family:"Courier
                                            New","serif""><br>
                                            <code>ENTITY
                                              conversion_based_unit_with_offset</code><br>
                                            <code>  SUBTYPE OF (</code></span><code><b><span
style="font-size:10.0pt;font-family:"Times","serif"">conversion_based_unit</span></b></code><code><span
                                              style="font-size:10.0pt">);</span></code><span
                                            style="font-size:10.0pt;font-family:"Courier
                                            New","serif""><br>
                                            <code>  offset : <a
                                                moz-do-not-send="true"
href="file:///%5C%5C%5C%5C%5C%5C%5C%5CUsers%5Ctom%5CDocuments%5C2013%5CSMRLv5%5CSMRL_v5_rc5%5Cdata%5Cresource_docs%5Cfundamentals_of_product_description_and_support%5Csys%5C18_schema.htm#measure_schema.measure_with_unit">R</a>EAL;</code><br>
                                            <code>WHERE</code><br>
                                            <code>  WR1: offset <>
                                              0.0;</code><br>
                                            <code>END_ENTITY;</code><br>
                                            <code>(*</code></span><o:p></o:p></p>
                                        <p><u><span
                                              style="font-size:13.5pt;font-family:"Times","serif"">Attribute
                                              definitions:</span></u><o:p></o:p></p>
                                        <p class="expressdescription"><a
                                            moz-do-not-send="true"
                                            name="measure_schema.conversion_based_unit.nam"><b><span
style="font-size:13.5pt;font-family:"Times","serif"">offset: </span></b></a><span
style="font-size:13.5pt;font-family:"Times","serif"">the value
                                            of the offset represented in
                                            the units of the
                                            conversion_factor inherited
                                            from
                                            the conversion_based_unit.</span><o:p></o:p></p>
                                        <p class="expressdescription"><u><span
style="font-size:13.5pt;font-family:"Times","serif"">Formal
                                              propositions:</span></u><o:p></o:p></p>
                                        <p class="expressdescription"><a
                                            moz-do-not-send="true"
                                            name="measure_schema.conversion_based_unit.wr:"><b><span
style="font-size:13.5pt;font-family:"Times","serif"">WR1: The
                                                offset shall not be
                                                zero.</span></b></a><o:p></o:p></p>
                                        <div>
                                          <p class="MsoNormal">Note: If
                                            the offset is zero, then the
                                            supertype <b><span
                                                style="font-family:"Times","serif"">conversion_based_unit
                                              </span></b><span
                                              style="font-family:"Times","serif"">is
                                              used.</span><o:p></o:p></p>
                                        </div>
                                      </div>
                                      <div>
                                        <div>
                                          <p class="MsoNormal">=========end
                                            proposed addition to part
                                            41=========<o:p></o:p></p>
                                        </div>
                                      </div>
                                      <div>
                                        <p class="MsoNormal"> <o:p></o:p></p>
                                      </div>
                                      <div>
                                        <p class="MsoNormal">On Jun 6,
                                          2014, at 3:29 PM, Martin
                                          Hardwick <<a
                                            moz-do-not-send="true"
                                            href="mailto:hardwick@steptools.com">hardwick@steptools.com</a>>
                                          wrote:<o:p></o:p></p>
                                      </div>
                                      <p class="MsoNormal"><br>
                                        <br>
                                        <br>
                                        <br>
                                        <br>
                                        <o:p></o:p></p>
                                      <div>
                                        <div
                                          style="margin-left:-.5in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-align:center"
                                            align="center"><b><span
                                                style="font-size:16.0pt">P21
                                                e3 DIS Testing</span></b><o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:-.5in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-align:center"
                                            align="center"><span
                                              style="font-size:14.0pt">Minutes
                                              of June 5, 2104 Telecon</span><o:p></o:p></p>
                                        </div>
                                        <h2>Attendees<o:p></o:p></h2>
                                        <p class="MsoNormal"
                                          style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Martin
                                          Hardwick
                                          <a moz-do-not-send="true"
                                            href="mailto:hardwick@steptools.com"><hardwick@steptools.com></a>
                                          <br>
                                          Robert Lipman <a
                                            moz-do-not-send="true"
                                            href="mailto:robert.lipman@nist.gov"><robert.lipman@nist.gov></a>
                                          <br>
                                          Michael Benda <a
                                            moz-do-not-send="true"
                                            href="mailto:mjbenda@rockwellcollins.com"><mjbenda@rockwellcollins.com></a>
                                          <br>
                                          Hedlind Mikael <a
                                            moz-do-not-send="true"
                                            href="mailto:mikael.hedlind@scania.com"><mikael.hedlind@scania.com></a>
                                          <br>
                                          Dave Loffredo <a
                                            moz-do-not-send="true"
                                            href="mailto:loffredo@steptools.com"><loffredo@steptools.com></a>
                                          <br>
                                          Ed Paff  <a
                                            moz-do-not-send="true"
                                            href="mailto:ejp@transcendata.com"><ejp@transcendata.com></a>
                                          <br>
                                          Tom Thurman <a
                                            moz-do-not-send="true"
                                            href="mailto:thomas.r.thurman@imonmail.com"><thomas.r.thurman@imonmail.com></a><o:p></o:p></p>
                                        <h2>Apologies for Absence<o:p></o:p></h2>
                                        <p class="MsoNormal"
                                          style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Jochen
                                          Fritz
                                          <a moz-do-not-send="true"
                                            href="mailto:jfritz@steptools.com"><jfritz@steptools.com></a>
                                          <o:p></o:p></p>
                                        <p class="MsoNormal"
                                          style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Nicolas
                                          Figay
                                          <a moz-do-not-send="true"
                                            href="mailto:nicolas.figay@eads.net"><nicolas.figay@eads.net></a>
                                          <br>
                                          <br>
                                          <br>
                                          <br>
                                          <br>
                                          <o:p></o:p></p>
                                        <h2>PMI Splitting<o:p></o:p></h2>
                                        <p class="htmlbody">ITI has
                                          split the sp3_boxy file
                                          produced by NIST into a
                                          geometry file and a pmi file.
                                          STEP Tools has viewed the
                                          geometry file and is working
                                          on a viewer for the separated
                                          pmi file. The two files and
                                          the original NIST data can be
                                          found at the following URL:<o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody"><a
                                            moz-do-not-send="true"
                                            href="ftp://www.steptools.com/private/P21e3_DIS_testing/PMI/">ftp://www.steptools.com/private/P21e3_DIS_testing/PMI/</a><o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody">STEP Tools
                                          is sponsoring the development
                                          of open source programs to
                                          split and merge P21 files
                                          using the Edition 3
                                          specification. The programs
                                          are available at the following
                                          URL:
                                          <a moz-do-not-send="true"
                                            href="http://tinyurl.com/thundercode">http://tinyurl.com/thundercode</a>.<o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <h2>ZIP Assemblies<o:p></o:p></h2>
                                        <p class="htmlbody">No visible
                                          progress has been made on this
                                          test case since the last
                                          telecom, but the PMI merge and
                                          split code is being updated to
                                          handle this case as well.<o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody"><a
                                            moz-do-not-send="true"
                                            href="ftp://www.steptools.com/private/P21e3_DIS_testing/ZIP_Assembly/">ftp://www.steptools.com/private/P21e3_DIS_testing/ZIP_Assembly/</a><o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody">In the last
                                          telecom:<o:p></o:p></p>
                                        <div
                                          style="margin-left:.5in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-.25in"><span
                                              style="font-family:Symbol">·</span><span
                                              style="font-size:7.0pt">        
                                            </span>We decided the
                                            sub-tree directory names
                                            should include the NUAO
                                            identifier(s) for their
                                            corresponding node in the
                                            assembly tree.<o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:.5in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-.25in"><span
                                              style="font-family:Symbol">·</span><span
                                              style="font-size:7.0pt">        
                                            </span>We learned that the
                                            LZMA algorithm has been
                                            shown to make STEP files
                                            three times more compressed
                                            than the more commonly used
                                            deflate algorithm, but at
                                            the cost of an increase in
                                            the compression time.<o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:.5in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-.25in"><span
                                              style="font-family:Symbol">·</span><span
                                              style="font-size:7.0pt">        
                                            </span>We learned that each
                                            compressed file is required
                                            to document the algorithm
                                            used for its compression in
                                            its header and that
                                            different components in the
                                            same ZIP can used different
                                            compression algorithms.<o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:.5in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-.25in"><span
                                              style="font-family:Symbol">·</span><span
                                              style="font-size:7.0pt">        
                                            </span>We recommended that
                                            the choice of the best
                                            compression algorithm should
                                            be left to the end user and
                                            that the standard should be
                                            silent on the matter.
                                            <o:p></o:p></p>
                                        </div>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody"><b> </b><o:p></o:p></p>
                                        <h2>Unit Definitions<o:p></o:p></h2>
                                        <p class="htmlbody">The unit
                                          definitions have been merged
                                          into a single file called
                                          units.stp.<o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody"><a
                                            moz-do-not-send="true"
                                            href="ftp://www.steptools.com/private/P21e3_DIS_testing/Units/">ftp://www.steptools.com/private/P21e3_DIS_testing/Units/</a><o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody">We continued
                                          our discussion on whether unit
                                          references should be encoded
                                          as a URL or a URN. The
                                          following two lines of code
                                          show equivalent URL’s and
                                          URN’s.<o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody"><a
                                            moz-do-not-send="true"
href="http://standards.iso.org/iso/10303/tech/reference_data/41/si_base_units.stp#METRE"><http://standards.iso.org/iso/10303/tech/reference_data/41/si_base_units.stp#METRE></a>;<o:p></o:p></p>
                                        <p class="htmlbody"><urn:iso:std:iso:10303:-41:tech:unit:metre>;<o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <div
                                          style="margin-left:63.0pt;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-63.0pt">Explanation
                                            of URN: <o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:1.0in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-1.0in">urn                         
                                            Indicates this URI is a URN,
                                            instead of the more common
                                            URL (http)<o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:1.0in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-1.0in">iso                          
                                            URN namespace  (other
                                            examples are oid, usbn)<o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:1.0in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-1.0in">std                          
                                            ISO standard  <o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:1.0in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-1.0in">iso                          
                                            originating organization
                                            (other examples are iec,
                                            iso-ies, iso-cie)<o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:1.0in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-1.0in">10303                   
                                            STEP standard
                                            <o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:1.0in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-1.0in">-41                         
                                            part of multipart standard
                                            (hyphens required)
                                            <o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:1.0in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-1.0in">Tech                      
                                            associated or embedded
                                            resource defined by
                                            committee that created the
                                            standard
                                            <o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:1.0in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-1.0in"><the
                                            rest>             
                                            unspecified -- controlled by
                                            committee.<o:p></o:p></p>
                                        </div>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody">In the above
                                          example, the URN has small
                                          advantage over the URL but
                                          perhaps the following URN will
                                          be acceptable because a file
                                          does not have to exist to
                                          define a URN.<o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody"><urn:iso:metre>;<o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody">It is also
                                          conceivable that the following
                                          URN might be acceptable even
                                          though there are currently
                                          small technical issues
                                          stopping the deployment of
                                          unit definitions for a
                                          Fahrenheit measure in a STEP
                                          file.<o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody"><urn:iso:Fahrenheit>;
                                          <o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody">We further
                                          discussed the requirements if
                                          all the unit definitions are
                                          to be defined in STEP files.
                                          The definition of literal
                                          constants such as PI, and
                                          EXPRESS constants such as
                                          negri_pi, have both led to
                                          extensive additions to the
                                          edition 3 format for which
                                          other strong use cases are
                                          currently lacking.<o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody">On the other
                                          hand the problem might be that
                                          we have not been sufficiently
                                          ambitious. It was pointed out
                                          that if constants can be
                                          defined then we are close to
                                          allowing expressions to be
                                          defined. The use of the PLIB
                                          schema for expressions has
                                          never been very satisfactory
                                          because the expressions are
                                          too hard to read when encoded
                                          into the STEP files. However,
                                          if Part 21 has an expression
                                          evaluation capability
                                          (probably in the anchors) then
                                          potential STEP applications
                                          such as parametrics and
                                          construction history might
                                          become more tractable. One
                                          interesting possibility might
                                          be to use Modelica as the
                                          expression language.<br>
                                          <br>
                                          <br>
                                          <br>
                                          <br>
                                          <o:p></o:p></p>
                                        <h2>Digital Signatures<o:p></o:p></h2>
                                        <p class="htmlbody">STEP Tools
                                          gave a demonstration of how to
                                          make a digital signature using
                                          a private key and a signing
                                          certificate and how to verify
                                          that a file has not been
                                          edited since it was signed
                                          using a public key.<o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody"><a
                                            moz-do-not-send="true"
href="ftp://www.steptools.com/private/P21e3_DIS_testing/Digital_signatures/">ftp://www.steptools.com/private/P21e3_DIS_testing/Digital_signatures/</a><o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody">We discussed
                                          white space and the issues
                                          that might arise if a file is
                                          read into Notepad/Wordpad and
                                          converted from line-feeds to
                                          carriage returns or vice
                                          versa. These characters are
                                          explicitly excluded from the
                                          Part 21 character set so they
                                          will not be included when
                                          computing and verifying the
                                          hash value.<o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody">We discussed
                                          supporting multiple
                                          signatures. The easiest
                                          procedure is for each
                                          signature to be applied to all
                                          of the characters that precede
                                          that signature. Thus each new
                                          signee is also verifying the
                                          signature of the previous
                                          signees.
                                          <o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <p class="htmlbody">For this to
                                          be consistent it would be best
                                          if the signatures came after
                                          the END-ISO-10303-21 keyword
                                          as shown in the example on the
                                          ftp site.<o:p></o:p></p>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <div
                                          style="margin-left:.5in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-.25in"><span
                                              style="font-family:Symbol">·</span><span
                                              style="font-size:7.0pt">        
                                            </span>The next conference
                                            call will be held on Friday
                                            June 27 at 4PM Paris, 3PM
                                            London, 10AM New York and
                                            7AM Seattle.<o:p></o:p></p>
                                        </div>
                                        <p class="htmlbody"> <o:p></o:p></p>
                                        <h2>Action Items<o:p></o:p></h2>
                                        <p class="htmlbody"
                                          style="margin-left:.5in;text-indent:-.25in">1.<span
                                            style="font-size:7.0pt">   
                                          </span>Complete the first ZIP
                                          assembly example.<o:p></o:p></p>
                                        <p class="htmlbody"
                                          style="margin-left:.5in;text-indent:-.25in">2.<span
                                            style="font-size:7.0pt">   
                                          </span>Consider the best
                                          approach for unit definitions:
                                          URN’s or URLs’?<o:p></o:p></p>
                                        <div
                                          style="margin-left:.5in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-.25in">3.<span
                                              style="font-size:7.0pt">   
                                            </span>Consider if Edition 3
                                            should offer any support to
                                            the definition of
                                            parametrics and if so how?<o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:.5in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-.25in">4.<span
                                              style="font-size:7.0pt">   
                                            </span>Extend the digital
                                            signatures example to
                                            include the creation of
                                            signing certificates.<o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:.5in;margin-right:-.5in">
                                          <p class="MsoNormal"
                                            style="text-indent:-.25in">5.<span
                                              style="font-size:7.0pt">   
                                            </span>Demonstrate signing
                                            at one site (ITI) and
                                            verification at another site
                                            (STEP Tools).<o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:.25in;margin-right:-.5in">
                                          <p class="MsoNormal"> <o:p></o:p></p>
                                        </div>
                                        <div
                                          style="margin-left:.25in;margin-right:-.5in">
                                          <p class="MsoNormal"> <o:p></o:p></p>
                                        </div>
                                        <p class="MsoNormal"
                                          style="text-autospace:ideograph-other">As
                                          recorded by Martin Hardwick
                                          <a moz-do-not-send="true"
                                            href="mailto:hardwick@steptools.com"><hardwick@steptools.com></a>
                                          <br>
                                          <br>
                                          <br>
                                          <br>
                                          <br>
                                          <o:p></o:p></p>
                                      </div>
                                      <p class="MsoNormal"
                                        style="text-autospace:ideograph-other"><span
                                          style="font-size:12.0pt"><Minutes_p21e3_DIS_conference_call_05062014.docx>_______________________________________________<br>
                                          wg11 mailing list<br>
                                          <a moz-do-not-send="true"
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                                            href="http://lists.steptools.com/mailman/listinfo/wg11">http://lists.steptools.com/mailman/listinfo/wg11</a></span><o:p></o:p></p>
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                                      style="text-autospace:ideograph-other"><span
                                        style="font-size:12.0pt"> </span><o:p></o:p></p>
                                    <div>
                                      <p class="MsoNormal"
                                        style="text-autospace:ideograph-other"><span
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                                        style="font-size:12.0pt"> </span><o:p></o:p></p>
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                              <p class="MsoNormal"
                                style="text-autospace:ideograph-other"><span
                                  style="font-size:12.0pt"><br>
                                  <br>
                                  <br>
                                  <br>
                                  <br>
                                  <br>
                                </span><o:p></o:p></p>
                              <pre>_______________________________________________<o:p></o:p></pre>
                              <pre>wg11 mailing list<o:p></o:p></pre>
                              <pre><a moz-do-not-send="true" href="mailto:wg11@steptools.com">wg11@steptools.com</a><o:p></o:p></pre>
                              <pre><a moz-do-not-send="true" href="http://lists.steptools.com/mailman/listinfo/wg11">http://lists.steptools.com/mailman/listinfo/wg11</a><o:p></o:p></pre>
                            </blockquote>
                            <p class="MsoNormal"
                              style="text-autospace:ideograph-other"><span
                                style="font-size:12.0pt"> </span><o:p></o:p></p>
                            <div>
                              <p class="MsoNormal"
                                style="text-autospace:ideograph-other"><span
                                  style="font-size:12.0pt">--
                                </span><o:p></o:p></p>
                              <p>beste Grüße / kind regards<br>
                                <br>
                                Dr.-Ing. Thomas Liebich<br>
                                Geschäftsführer / Director <o:p></o:p></p>
                              <div class="MsoNormal"
                                style="text-align:center;text-autospace:ideograph-other"
                                align="center">
                                <span style="font-size:12.0pt">
                                  <hr align="center" size="2"
                                    width="100%">
                                </span></div>
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                                <tbody>
                                  <tr>
                                    <td style="width:40.0%;padding:.75pt
                                      .75pt .75pt .75pt" valign="top"
                                      width="40%">
                                      <p><span style="font-size:10.0pt">AEC3
                                          Deutschland GmbH<br>
                                          AG München, Handelsregister
                                          HRB 164221<br>
                                          Geschäftsführer: Dr. Thomas
                                          Liebich, Kerstin Hausknecht</span><o:p></o:p></p>
                                    </td>
                                    <td style="width:40.0%;padding:.75pt
                                      .75pt .75pt .75pt" valign="top"
                                      width="40%">
                                      <p><span style="font-size:10.0pt">Wendl-Dietrich-Str.
                                          16, D-80634 München<br>
                                          Tel: +49-89-18703223<br>
                                          Fax: +49-89-18703224</span><o:p></o:p></p>
                                    </td>
                                    <td style="width:20.0%;padding:.75pt
                                      .75pt .75pt .75pt" valign="top"
                                      width="20%">
                                      <p><span style="font-size:10.0pt">E-Mail:
                                          <a moz-do-not-send="true"
                                            href="mailto:tl@aec3.de">tl@aec3.de</a><br>
                                          Internet: <a
                                            moz-do-not-send="true"
                                            href="http://www.aec3.de">www.aec3.de</a><br>
                                           </span><o:p></o:p></p>
                                    </td>
                                  </tr>
                                  <tr>
                                    <td colspan="3" style="padding:.75pt
                                      .75pt .75pt .75pt">
                                      <p style="color:grey"><span
                                          style="font-size:7.5pt">Der
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                                          (einschließlich etwaiger
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                                          löschen Sie die E-Mail
                                          (einschließlich etwaiger
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                                          <em>This email and any
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                              </table>
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                                style="text-align:center;text-autospace:ideograph-other"
                                align="center">
                                <span style="font-size:12.0pt">
                                  <hr align="center" size="2"
                                    width="100%">
                                </span></div>
                            </div>
                            <p class="MsoNormal"
                              style="text-autospace:ideograph-other"><span
                                style="font-size:12.0pt"><br>
                                <br>
                                <br>
                                <br>
                                <br>
                                <br>
                              </span><o:p></o:p></p>
                            <pre>_______________________________________________<o:p></o:p></pre>
                            <pre>wg11 mailing list<o:p></o:p></pre>
                            <pre><a moz-do-not-send="true" href="mailto:wg11@steptools.com">wg11@steptools.com</a><o:p></o:p></pre>
                            <pre><a moz-do-not-send="true" href="http://lists.steptools.com/mailman/listinfo/wg11">http://lists.steptools.com/mailman/listinfo/wg11</a><o:p></o:p></pre>
                          </blockquote>
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                            style="text-autospace:ideograph-other"><span
                              style="font-size:12.0pt"> </span><o:p></o:p></p>
                        </div>
                      </blockquote>
                      <p class="MsoNormal"
                        style="text-autospace:ideograph-other"><span
                          style="font-size:12.0pt"> </span><o:p></o:p></p>
                    </div>
                  </blockquote>
                  <blockquote
                    style="margin-top:5.0pt;margin-bottom:5.0pt">
                    <div>
                      <p class="MsoNormal"
                        style="text-autospace:ideograph-other"><span
                          style="font-size:12.0pt">_______________________________________________<br>
                          wg11 mailing list<br>
                          <a moz-do-not-send="true"
                            href="mailto:wg11@steptools.com">wg11@steptools.com</a><br>
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                            href="http://lists.steptools.com/mailman/listinfo/wg11">http://lists.steptools.com/mailman/listinfo/wg11</a></span><o:p></o:p></p>
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                  style="text-autospace:ideograph-other"><span
                    style="font-size:12.0pt"> </span><o:p></o:p></p>
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                style="text-autospace:ideograph-other"><span
                  style="font-size:12.0pt"> </span><o:p></o:p></p>
            </div>
          </blockquote>
          <p class="MsoNormal" style="text-autospace:ideograph-numeric
            ideograph-other"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
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