Web-based Digital Twins for Smart Cities

14 September 2022


Bladley_Needham, Daihei_Shiohama, Dan_Duruta, David_Ezell, Debbie_Dahl, Eric_Siow, Gyu_Myoung_Lee, Hiroshi_Ota, Jim_Luth, Kaz_Ashimura, Kunihiko_Toumura, Michael_Cooper, Michel_McCool, Phil_Archer, Shuji_Hirakawa, Takashi_Kasuya, Tantek Çelik, Tetsushi_Matsuda, Tomoaki_Mizushima, Yan_Zhang

Meeting minutes

Kaz: thank you for coming
… (self-introduces)
… would like to talk about web-based digital twins

<kaz> https://www.w3.org/2022/Talks/0914-smartcities-ka/20220914-dt-sc-ka.pdf

Kaz: will first define scope, what has been done so far, what is missing, then discussion on how to resolve gaps
… as background, we had a workshop and identified a LOT of problems
… and we also need feedback from stakeholders, including smart cities
… out of this we generated a charter, but still need to identify and include more stakeholders, so are revisiting

Kaz: (summarizes presentations from workshop)

Kaz: summarize what has been done
… we have been working with ECHONET, IoT SDO from Japan
… working with IEC SC3D, working on IoT ontologies
… and IPA, Takanaka has been working on BIM, and now working on a smart city project in Osaka, already using WoT
… TC1/JG11 also working on some projects
… ITU-T SG20 and some related groups
… and there is a prototype smart sity

Kaz: what is missing?
… (slides)
… OGC standards and digital twins
… finally W3C: not just HTML, but lots of other data transfer technologies
… and web standards have been applied to various industries
… still have a big problem with IoT silos and fragmentation
… Takanaka has demonstrated integration
… but still have a problem with common semantic vocabulary
… still need guidelines for discovery, inter-system binding, ID auth and management, standard vocabulary, accessibility, geolocation
… governance of data distribution: security, where to start with data search

Kaz: how can be organize the discussion to resolve these gaps?

Kaz: "Digital Twins" is commonly mentioned, might be a good place to start
… would like therefore to start with web-based digital twins
… since we already had a workshop, and we already have a lot of use cases, we should consolidate
… so should we start with a CG or IG?
… this morning we also talked with DID/VC, and can integrate with WoT to create a common framework
… WoT can be used for devices, DID can be used for other entities

McCool: we generated a draft Charter for the potential IG

McCool: why did we not just proceed with an IG and the charter we developed?

Kaz: need more stakeholders

McCool: perhaps we should reopen the charter and revise it as needed

Kaz: think "smart cities" is still too broad, want to narrow further

Jim: OGC has also been doing work in smart cities
… but there is no clear definition of "smart city", but we also have been looking at digital twins
… better connected to goals of data sharing and analysis (esp spatial-temporal) of OGC

<Zakim> MichaelC, you wanted to ask more about what the web-based digital twin proposal is and to ask how digital twin differs from other exchange mechanisms

Jim: agree that DT is a good focus, will help clarify smart city concept

McCool: coming from outside, want to understand how smart cities and digital twins connect

Kaz: DT is basically a virtualization of actual environment
… such a mechanism should be useful for managing and providing services

McCool: to me twin meant "city twinning" which I understand is different concept

Jim: many tools enable a digital representation of various aspects of the real system: looks the same, behaves the same, but is not the same

Jim: also recognition that social dimension is also important
… connection between physical and digital is still important
… has an affinity with concepts of models

McCool: even "Digital Twins" may be still too broad
... we should narrow the purpose and clarify our points
... also different kind of data to be handled
... not only geolocation but also temporal data, etc.
... combination of IoT device and geolocation, for example

Jim: totally agree
... absolutely right
... for example, it comes to my mind around energy consumption
... take action to solve problems
... there are sensors and actuators

Yan: do have projects for smart cites in did/vc
… looking at metaverse applications, in particular event management, stadiums, temples
… part missing in all projects is confidential computing
… need privacy protection
… need secure enclaves
… need to add this aspect
… ex project in Toronto got a lot of complaints for not respecting privacy
… mapping people into virtual worlds can "trap" them
… feel there are two direction: privacy, and then a focus on users

Kaz: many similar discussions in workshop

<Zakim> kaz, you wanted to react to YanZhang

GyuMyoung: regarding digital twin, is important direction to compose physical and cyber space
… but how to do that is the important thing
… there are lots of efforts and different dimensions
… also in case of web3 and metaverse, lots of things to consider

<Zakim> dezell, you wanted to ask about twins in retail

David: wanted to second some comments; here representing retail
… stores care about similar things as cities
… have traffic, cameras, making sure that things that are supposed to happen do happen
… other similar environments would be a laboratory, or a kitchen
… point about confidential computing
… iot is the physical reality input into the DT
… two big problems
… one is replay
… can imagine an attacker spoofing data

<Josh-OGC> The chain of links between a sensor reading and an interpretation of the world is described by the OGC/ISO standard Observations and Measurements, also modeled by the W3C ontology SOSA/SSN

David: and the other is fingerprinting, AI can watch that data and make inferences
… both those things are hard to get around

<tantek_> +1 concerned about fingerprinting

Yan: and all that data needs to be processed, typically with an AI algorithm
… often want to use a cloud services, but too much bandwidth, need edge computing

McCool: part of the draft IG Charter suggests we collaborate with the related groups

<Josh-OGC> Important to remember that there is an inevitable tension between confidentiality of data and transparency of (e.g. ML) interpretations.

<kaz> Draft IG Charter

McCool: thinking about digital twins, can use for modelling
… who are the users? metaverse visitors? citizens?

<Zakim> MichaelC, you wanted to ask if digital twins and metaverse would intersect

Jim: talked about different representations
… DT is useful just as an organizing concept
… consistency between DT and world
… also clear there will not be one DT but different aspects
… but do need to use consistent data, e.g. the same maps

Kaz: consistency also arises in ontologies as well. how to choose necessary ontologies/DTs is a good question

<Josh-OGC> The basis of any start in digital twins is indeed a consistent spatial data framework.

David: does current charter include digital twin
… but wonder if smart city should be in quotes, and focus be on digital twins
… from the marketing point of view, smart cities is a useful concept

McCool: agree the target is still too broad
... all of stores, buildings and cities are important

<Josh-OGC> The different scales of digital twins benefit and suffer from the same scale and unit area concerns of classical spatial analysis, just in more dimensions.

McCool: worried about scope, different technologies for retail, BIM, smart cities
... for example, building is part of cities

McCool: would prefer narrow scope, but don't know if we CAN decouple buildings and cities

Dan: we have digital twins for networks
… use simulation all the time in other areas

<Josh-OGC> OGC is supporting activities in both "Urban" Digital Twins and "Environmental" Digital Twins. Jet engines, a bit less so.

Dan: parallel that david was using for retail is interesting
… but in city are talking about different sensor networks owned by different owners
… in retail, single owner
… this needs to be taken into account, data sharing is much harder

McCool: I agree
... different smart cities use different mechanisms and don't share information with each other

McCool: cities are also very fragmented
… even hard to get departments to work together
… silos

Yan: agree with that, have seen that as well
… not only departments, but adjacent regions may not use the same standards

<DanD> https://www.atis.org/resources/smart-cities-data-catalog-specification/

<Josh-OGC> Successful smart cities have a data "czar" with some authority to collect, harmonize, and disseminate data, really creating incipient UDT's

Yan: even time series database sharing

McCool: reminded me of the WoT Demo
... what we're still missing is expressing transformation data ... mapping into common construction ... the way to express the structure ... maybe we need to look into some kind of transmation mechanism like XSL

McCool: I do think data alignment and mapping are one of the key problems

Kaz: agree we should look at mechanisms to connect different silos
… this morning we had a discussion with did/vc, and internal collaboration

<Zakim> kaz, you wanted to react to YanZhang

Jim: another aspect is bilateral transformation are a dead end

Jim: having an integration model that other silos can converge on
… have been working on such common models for infrastructure
… but so far have only got one model built
… not for lack of tools, but from lack of culture

McCool: honestly, the workshop was great but no citizens attended
... that is a big problem
... number of effort for citizens is quite low

McCool: do think big problem is getting cities to the table

Jim: plug for OGC, group has been working on developing a set of practices
… then there is a set of expectations and appropriate tools to accomplish various missions

Kaz: I would like to ask SDO people who have not yet raised their hands
… if they have any comments or questions, for example, regarding BIM

<Josh-OGC> Just to clarify, Spatial Data on the Web is a joint OGC - W3C group with shared membership.

Yamashita: IEC, not only focused on smart city, but providing common ontologies for devices and sensors

<Josh-OGC> Sorry: https://www.w3.org/groups/wg/sdw

Yamashita: common understanding of available devices and assets
… is necessary and related to data models for digital twin, should be included in this group
… digital twin is not only for smart cities, already widely used in manufacturing
… and we can refer to existing use cases in other domains

Kaz: collecting that kind of existing best practices will be important

Kasuya: I think web based technologies are necessary for digital twins and for smart buildings
… so we definitely want to keep in touch

Kaz: also, you are working on actual smart city projects so should have some concrete goals

Kasuya: we must use automation to create data models
… we are currently researching this topic

Kaz: need some kind of organization

<tantek_> +1 McCool_ create a CG before considering creating an IG

McCool: what are next steps? Can we send invitation to people here to another meeting?

Kaz: will do that
... I'll generate a ML including people here, and also we can use GitHub for further discussion, e.g., reviewing the draft Charter

<kaz> [adjourned]

Minutes manually created (not a transcript), formatted by scribe.perl version 192 (Tue Jun 28 16:55:30 2022 UTC).