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      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:<br>
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        <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">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.<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">urn:iso:
            ... is a well-defined identifier form, and ISO CS is the
            registry for it.  See IETF RFC 5141.
            (<a class="moz-txt-link-freetext" href="http://www.rfc-editor.org/info/rfc5141">http://www.rfc-editor.org/info/rfc5141</a>)<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">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.<o:p></o:p></span></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):<o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">   
            urn:iso:std:iso:31:term:metre<o:p></o:p></span></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.<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">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:<o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">  
            urn:iso:std:iso:10303:tech: xxx<o:p></o:p></span></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.<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">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:<o:p></o:p></span></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
            <o:p></o:p></span></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<o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> 
            <a class="moz-txt-link-freetext" href="http://iso.org/std/iso/15926/-4#">http://iso.org/std/iso/15926/-4#</a> INCHES_PER_SECOND<o:p></o:p></span></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.<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">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. 
            <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>
        <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">
          <div>
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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">
                  wg11 [<a class="moz-txt-link-freetext" 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<o:p></o:p></span></p>
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          <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%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%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%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%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><span
                            style="font-size:13.5pt;font-family:"Times","serif""><o:p></o:p></span></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%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%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%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><span
                            style="font-size:13.5pt;font-family:"Times","serif""><o:p></o:p></span></p>
                        <div>
                          <p class="MsoNormal"><u><span
                                style="font-size:13.5pt;font-family:"Times","serif"">EXPRESS
                                specification:</span></u><span
                              style="font-size:13.5pt;font-family:"Times","serif""><o:p></o:p></span></p>
                        </div>
                        <p><code><span style="font-size:10.0pt">*)</span></code><span
                            style="font-size:10.0pt;font-family:"Courier
                            New""><br>
                            <code>ENTITY conversion_based_unit</code><br>
                            <code>  SUBTYPE OF (</code></span><a
                            moz-do-not-send="true"
href="file:///%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"">named_unit</span></a><code><span
                              style="font-size:10.0pt">);</span></code><span
                            style="font-size:10.0pt;font-family:"Courier
                            New""><br>
                            <code>  name : </code></span><a
                            moz-do-not-send="true"
href="file:///%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"">label</span></a><code><span
                              style="font-size:10.0pt">;</span></code><span
                            style="font-size:10.0pt;font-family:"Courier
                            New""><br>
                            <code>  conversion_factor : </code></span><a
                            moz-do-not-send="true"
href="file:///%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"">measure_with_unit</span></a><code><span
                              style="font-size:10.0pt">;</span></code><span
                            style="font-size:10.0pt;font-family:"Courier
                            New""><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><span
                            style="font-size:13.5pt;font-family:"Times","serif""><o:p></o:p></span></p>
                        <p><u><span
                              style="font-size:13.5pt;font-family:"Times","serif"">Attribute
                              definitions:</span></u><span
                            style="font-size:13.5pt;font-family:"Times","serif""><o:p></o:p></span></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%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.<o:p></o:p></span></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%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.<o:p></o:p></span></p>
                        <p><u><span
                              style="font-size:13.5pt;font-family:"Times","serif"">Formal
                              propositions:</span></u><span
                            style="font-size:13.5pt;font-family:"Times","serif""><o:p></o:p></span></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%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"">.<o:p></o:p></span></p>
                        <div>
                          <p class="MsoNormal"><span
                              style="font-size:12.0pt"><o:p> </o:p></span></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 </span><span
style="font-size:13.5pt;font-family:"Times","serif"">  
                            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%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%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><span
                            style="font-size:13.5pt;font-family:"Times","serif""><o:p></o:p></span></p>
                        <p><u><span
                              style="font-size:13.5pt;font-family:"Times","serif"">EXPRESS
                              specification:</span></u><span
                            style="font-size:13.5pt;font-family:"Times","serif""><o:p></o:p></span></p>
                        <p><code><span style="font-size:10.0pt">*)</span></code><span
                            style="font-size:10.0pt;font-family:"Courier
                            New""><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""><br>
                            <code>  offset : <a moz-do-not-send="true"
href="file:///%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><span
                            style="font-size:13.5pt;font-family:"Times","serif""><o:p></o:p></span></p>
                        <p><u><span
                              style="font-size:13.5pt;font-family:"Times","serif"">Attribute
                              definitions:</span></u><span
                            style="font-size:13.5pt;font-family:"Times","serif""><o:p></o:p></span></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.<o:p></o:p></span></p>
                        <p class="expressdescription"><u><span
                              style="font-size:13.5pt;font-family:"Times","serif"">Formal
                              propositions:</span></u><span
                            style="font-size:13.5pt;font-family:"Times","serif""><o:p></o:p></span></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><span
style="font-size:13.5pt;font-family:"Times","serif""><o:p></o:p></span></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><span style="font-size:12.0pt"><o:p></o:p></span></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>
                        <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>
                          <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>
                          <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-numeric
                          ideograph-other">As recorded by Martin
                          Hardwick
                          <a moz-do-not-send="true"
                            href="mailto:hardwick@steptools.com"><hardwick@steptools.com></a>
                          <br>
                          <br>
                          <span style="font-size:12.0pt"><o:p></o:p></span></p>
                      </div>
                      <p class="MsoNormal"
                        style="text-autospace:ideograph-numeric
                        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"
                            href="mailto:wg11@steptools.com">wg11@steptools.com</a><br>
                          <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></span></p>
                    </div>
                    <p class="MsoNormal"
                      style="text-autospace:ideograph-numeric
                      ideograph-other"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
                    <div>
                      <p class="MsoNormal"
                        style="text-autospace:ideograph-numeric
                        ideograph-other"><span class="apple-style-span"><span
                            style="font-size:12.0pt">Notice: This e-mail
                            (including attachments) is covered by the
                            Electronic Communications Privacy Act, 18
                            U.S.C. 2510-2521, is confidential and may
                            be legally privileged.  If you are not the
                            intended recipient, you are hereby notified
                            that any retention, dissemination,
                            distribution, or copying of this
                            communication is strictly prohibited.
                             Please reply to the sender that you have
                            received the message in error, then delete
                            it.  Thank you.</span></span><span
                          style="font-size:12.0pt"><br>
                          <br>
                          <br>
                          <o:p></o:p></span></p>
                    </div>
                    <p class="MsoNormal"
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                      ideograph-other"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
                  </div>
                </div>
              </div>
              <p class="MsoNormal"
                style="text-autospace:ideograph-numeric ideograph-other"><span
                  style="font-size:12.0pt"><br>
                  <br>
                  <br>
                  <o:p></o:p></span></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-numeric
              ideograph-other"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
            <div>
              <p class="MsoNormal"
                style="text-autospace:ideograph-numeric ideograph-other"><span
                  style="font-size:12.0pt">--
                  <o:p></o:p></span></p>
              <p>beste Grüße / kind regards<br>
                <br>
                Dr.-Ing. Thomas Liebich<br>
                Geschäftsführer / Director <o:p></o:p></p>
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                </span></div>
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                  <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<o:p></o:p></span></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<o:p></o:p></span></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>
                           <o:p></o:p></span></p>
                    </td>
                  </tr>
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                      .75pt">
                      <p style="color:grey"><span
                          style="font-size:7.5pt">Der Inhalt dieser
                          E-Mail (einschließlich etwaiger beigefügter
                          Dateien) ist vertraulich und nur für den
                          Empfänger bestimmt. Sollten Sie nicht der
                          bestimmungsgemäße Empfänger sein, ist Ihnen
                          jegliche Offenlegung, Vervielfältigung,
                          Weitergabe oder Nutzung des Inhalts untersagt.
                          Bitte informieren Sie in diesem Fall
                          unverzüglich den Absender und löschen Sie die
                          E-Mail (einschließlich etwaiger Anhänge) von
                          Ihrem System. |
                          <em>This email and any attachments are
                            confidential to the intended recipient and
                            may also be privileged. If you are not the
                            intended recipient please delete it from
                            your system and notify the sender. You
                            should not copy it or use it for any purpose
                            nor disclose or distribute its contents to
                            any other person.</em> <o:p></o:p></span></p>
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              </table>
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                <span style="font-size:12.0pt">
                  <hr align="center" size="2" width="100%">
                </span></div>
            </div>
            <p class="MsoNormal" style="text-autospace:ideograph-numeric
              ideograph-other"><span style="font-size:12.0pt"><br>
                <br>
                <br>
                <o:p></o:p></span></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-numeric
            ideograph-other"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
        </div>
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    </blockquote>
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