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Subject: RE: [emergency] RE: Sample email to interestedpartiesWRTgeoenhancements to CAP
As I said in an earlier email, support of the new Chinese datum in gospatial data formats, encodings, or software is a mandate in China. This is a perfect example of what Ron is referring to as a local requirement. The rationale for the Chinese requirement is that th new datum is much more accurate than WGS 84 for the majority of China. Carl > Art: > > Then one says that for such devices there is only one CRS and this is > specified by a particular CRS registry entry. In either case the > specification of the CRS MUST be unambiguous, Just agreeing on say > (lat,lon) will not be enough if the different users select for example > different datums as this will lead to the same (lat,lon) corresponding > to different places on the earth. > > Since at the present time, there are not a great number of truly global > alerts - it could make sense to have the single CRS used in one part of > the world differ from that in another part of the world - I think the > key issue is to eliminate ambiguity in the meaning of coordinates. > > Ron > > -----Original Message----- > From: Art Botterell [mailto:ABott@so.cccounty.us] > Sent: November 26, 2007 5:17 PM > To: Ron Lake; emergency@lists.oasis-open.org; sandro@oss.com > Subject: Re: [emergency] RE: Sample email to > interestedpartiesWRTgeoenhancements to CAP > > Ron, that makes perfect sense for full-blown GIS installation, but what > about cellphones and wristwatches and mass-market alerting devices? > What about systems that receive broadcast, one-way signals? If they > can't access these remote lookup/conversion services, significant errors > could result. > > I'd encourage any of us who weren't around for our earlier CAP > proceedings to at least review the introductory text of the current > spec. I suspect some aspects of the application domain that may not be > obvious, especially for folks who come from an IT background more than a > telecommunications perspective. > > - Art > -----Original Message----- > From: "Ron Lake" <rlake@galdosinc.com> > To: <emergency@lists.oasis-open.org> > To: <sandro@oss.com> > To: Botterell, Art <ABott@so.cccounty.us> > > Sent: 11/26/2007 5:03:20 PM > Subject: RE: [emergency] RE: Sample email to interested > partiesWRTgeoenhancements to CAP > > Hi Art: > > I think this is a good point. Suppose you use GML geometries in CAP > constructs. For example, a GML point is encoded as follows: > > <gml:Point srsName = "urn:x-ogc:def:crs:EPSG:4326"> > <gml:pos>45.7 110.6</gml:pos> > </gml:Point> > > The srsName attribute indicates the CRS in use. This does NOT need to > be resolved in real time, but those wishing to consume or generate this > data may wish to look this up. This can be done using a registry such as > > at http://www.epsg-registry.org and entering the URN string or the EPSG > code. A giving alerting community (the whole world or the US or > whatever) can select the set of CRS definitions that they permit. > > If you do not understand the srsName (there could be a default value > also) then you need to talk to a conversion service or request the data > in an srsName you do understand. > > Cheers > > Ron > > > -----Original Message----- > From: Art Botterell [mailto:ABott@so.cccounty.us] > Sent: November 26, 2007 4:38 PM > To: emergency@lists.oasis-open.org; sandro@oss.com > Subject: Re: [emergency] RE: Sample email to interested > partiesWRTgeoenhancements to CAP > > Let's keep our eye on the ball here. Our goal isn't adoption of CAP for > > its own sake and at any cost. The purpose of CAP is to achieve > interoperability among warning systems globally. > > If we start to sacrifice interoperability in pursuit of nominal > adoptions that can't actually communicate with each other, I'm afraid > we'll be justly criticised for having lost sight of our real mission. > > - Art > > > --------------------------------------------------------------------- > To unsubscribe from this mail list, you must leave the OASIS TC that > generates this mail. You may a link to this group and all your TCs in > OASIS > at: > https://www.oasis-open.org/apps/org/workgroup/portal/my_workgroups.php > > > --------------------------------------------------------------------- > To unsubscribe from this mail list, you must leave the OASIS TC that > generates this mail. You may a link to this group and all your TCs in > OASIS > at: > https://www.oasis-open.org/apps/org/workgroup/portal/my_workgroups.php > > >
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