00:01I’ve chosen to spend my five minutes telling you about something that’s very exciting that I think we can all use. CityGML.

00:09I’m not an author of CityGML; I played a small role in its development and application and...as can we all. I think the importance...

00:18...of this...this modeling idea in...in this environment is that I see that the difficulty of sharing and integrating our knowledge about places...

00:33...and processes is one of the biggest impediments to realizing the vision of GeoDesign.

00:41Each of us is working on a piece of the puzzle.

00:44Each of us has our own area of expertise and uses our own tools to understand a piece of this puzzle.

00:52And if we can better join our forces and share our information, we will soon be able to combine our ideas and our knowledge into...

00:58...something much greater than what Jack has called “societal GIS.”

01:05The workflows in...in GeoDesign have been talked about a lot in this conference.

01:10They begin by pulling data out of an information infrastructure, usually, and a cycle of representation and evaluation that ends up...

01:19...with generating new knowledge about places and processes.

01:23Hopefully, that new knowledge will make it into...back into the information infrastructure, so that it can be reused, instead of simply...

01:33...starting from scratch each time.

01:35Today most of us are takers from the information infrastructure.

01:38Hopefully in the future we’ll contribute our pieces to a greater knowledge of places and processes.

01:45If we look a little bit more closely at these workflows, we can see often, in...in my case always...

01:52...they involve a community of different specialized tools.

01:56There’s no one package that has all of the knowledge that we need in it.

02:01And so, part of the puzzle is connecting these tools together.

02:06And currently one of the gigantic frustrations is that, in moving information from one tool to another, we throw away important...

02:14...critical knowledge.

02:17An example. GIS to CAD or to BIM.

02:22A lot of information goes into the semantic trash bin as we try to move data from...

02:27...about context into more specific modeling tools, like BIM.

02:33And actually, as we move it back, there’s often another semantic dump that happens.

02:38Very annoying.

02:41If...just to think about this more systematically involves thinking about, what are the concepts that are critical to our understanding of a place?

02:51And so, here’s a very simple example. We’ve got a building probably coming from a BIM tool.

02:57We’ve got terrain that’s probably coming from a GIS tool.

03:01And there’s the relationships between the building and the terrain.

03:04The designer has designated that the terrain should meet the building along a specific line.

03:09So even though these concepts are coming from different tools, we can formalize these relationships in a conceptual model that we can share.

03:21And if that conceptual model is instantiated in software, then that software, it doesn’t need to be open source software...

03:31...it just needs to substantiate some subset of these concepts, and to meet its business processes.

03:38But as a result, if we have two tools that instantiate the same subsets of concepts from this shared model, say the GIS tool...

03:48...with its terrain and the BIM tool with its buildings these tools can interoperate, and a third tool will be able to render the...

03:55...building on the terrain with the terrain meeting the building as the designer intended.

04:02These are two...three simple concepts from CityGML.

04:06Now I just want to show you a couple of examples of how we all are contributing pieces to the puzzle.

04:13In an urban setting, in an urban government, we have these different departments, all using their own tools, all contributing...

04:20...their knowledge from specific areas of expertise.

04:24And, in some cities, they are able to integrate this into a...an operational picture of the city, and that’s great, and that’s thanks largely to...

04:35...the efforts of...of the Esri folks and others.

04:40Now, if we look more broadly, here’s Boston, we’ve got a multitude of different territorial domains.

04:48And they’re all using different tools, they all have different conceptual models of what’s going on, and this is a much diff...

04:55...more difficult problem.

04:57If we want to have an operational picture of the metropolitan region, we need to settle on some common terms for how to...we identify the city.

05:07Another dimension of GeoDesign that hasn’t really come up that often here at this conference is the time dimension.

05:13If we can express our view of the city in common terms consistently, eventually we’ll be able to compare the current scenario with...

05:24...various past scenarios to get a better knowledge to use our memory to get an understanding of urban mechanics...

05:32...and how the context of change leads to one situation or another, and therefore we’ll be able to model possible scenarios...

05:40...and planned scenarios using that same terminology to get a better idea of the probable consequences of our decisions.

05:49So, how does CityGML relate to this?

05:52CityGML is a framework for conceptual models and for exchange encodings.

05:59Within CityGML, there are submodels that are componentized, for example, the building model, and this will relate...

06:06...to something that John said.

06:08Buildings can be rep...any particular building can be represented at multiple levels of detail, from a...just a blocky massing...

06:16...model to a level of detailed floor model that includes interior spaces and rooms.

06:22And so, this is information that, as John said, comes from...is also modeled in the Kobe specification, also modeled in BISDM, and if...if these different...

06:34...communities can agree on a subset of concepts that they have in common, CityGML can be a framework for allowing people to...

06:44...contribute their building models to this...this conglomeration of ideas.

06:49Other subsets of CityGML include a hydrological model, allowing us also to represent terrain at different levels of detail, to bring terrain...

06:58...in from different sources, and have them overlap in some logical fashion.

07:04We can model the forest, we can model the trees.

07:08Currently, the subgroup is working on a transpiration...transportation network model.

07:14And the beauty of having a master model with simple subset components that we can pull out is that one group can be working on the...

07:25...transportation model, another group can be working on the landscape model, and each of those groups will know that their investments...

07:31...of time and knowledge will accumulate to a logically consistent, coherent model of the city that we can all use to...

07:42...as a framework for attaching our own ideas about places and processes.

07:48Of course, the model is never finished.

07:51And model like this has to have a government’s process for developing, extending it.

07:58So, with CityGML, it’s being managed by OGC CityGML working group, a collaboration of all sorts of domain communities, you can...

08:09...join this to extend CityGML.

08:12You can extend CityGML right now for your own purposes, but if you feel like your extensions are worthy of...

08:18...being...coming ens...ensconced in the standard, then you can join this process.

08:25Assured stable environments and...for exchange and encoding of our knowledge will lead to more confidence, people inve...making substantial...

08:35...investments in encoding their knowledge and sharing it, making specialized tools that can do really specialized things with this knowledge...

08:47...and lots of interoperable content, better understanding of the world.

08:53So, let’s get it together.

08:57I encourage you to explore all the different open standards for encoding and exchanging knowledge, including CityGML.

09:06When you’re developing your own conceptual models, try to use conceptual models that have already been hammered out...

09:12...by...through this process.

09:15That will enable you to...to integrate your knowledge with others more easily.

09:19Participate in the development of standards, and develop and demand that your tools that you buy be able to exchange knowledge...

09:28...using open standards.

09:31Here’s some references, and if you’re looking at this on the video, you can go to that link to get this PDF.