Enhancing Interoperability of Digital Twins Based on Digital Twins

Definition Language

Salvatore Cavalieri

and Salvatore Gambadoro

Department of Electrical Electronic and Computer Engineering, University of Catania, Catania-95125, Italy

Keywords: Interoperability, Digital Twin, DTDL, OPC UA, Industry 4.0.

Abstract: The Industry 4.0 is featured by a continuously-evolving digital transformation, aiming to automate all the

traditional industrial practices. Digital Twin is one of the most important solutions to reach this aim. Among

the standards currently available to realize Digital Twins there is the Digital Twins Definition Language.

Digital Twin requires exchange of data with the real system it models and with other applications which use

the digital replica of the system. In the context of Industry 4.0, a reference standard for an interoperable

exchange of information between applications, is Open Platform Communications Unified Architecture. The

idea behind the paper is to exploit this standard to allow a Digital Twin based on Digital Twins Definition

Language to exchange data with any applications compliant to the Open Platform Communications Unified

Architecture. A proposal about the mapping from Digital Twins Definition Language to Open Platform

Communications Unified Architecture will be presented and discussed in this paper.

1 INTRODUCTION

Industry 4.0 is featured by a continuously-evolving

digital transformation, aiming to automate all the

traditional industrial practices. Among the several

solutions to reach this aim, there is the Digital Twin

(DT), bringing as much of the equipment from the

physical space into the virtual domain. Digital Twins

emerged as an experimental technology set to enable

replication of elements, functions, operations and

dynamics of physical systems into digital world, with

better control at testing, analysis, prediction and

hazard prevention for sensitive processes (Mihai,

2022; Rocha, 2022).

Digital Twins are used in different industrial

settings, including health surveillance, agriculture,

smart cities, smart grids, manufacturing,

meteorology, education and automobiles. Digital

Twins support the development of production

processes making them reliable and flexible, enabling

to visualise, monitor and optimize processes (Mihai,

2022; Rocha, 2022; Rasheed, 2020).

Different organisations are currently working

aiming to standardize Digital Twin definition,

interoperability and how to interact with these Digital

https://orcid.org/0000-0001-9077-3688

https://orcid.org/0000-0001-9840-1379

Twins. Two notable projects in this area are the Asset

Administration Shell (AAS) (Plattform Industrie 4.0,

2020; Pribiš, 2021; Jacoby, 2020) and the Digital

Twin Definition Language (DTDL) (DTDL, 2023).

The DTDL was born as an open source initiative by

Microsoft and it is already used in many commercial

services offered by Microsoft like IoT Hub, IoT

Central, and Azure Digital Twins (Jacoby, 2020;

DTDL, 2023).

One of the main features of a Digital Twin is the

communication with the physical world, from which

a Digital Twin must receive the current state (e.g.,

collection of data measured by sensors). At the same

time, a Digital Twin may have the need to exchange

data with different applications in order to realize

particular processes according to the aims to be

reached (e.g., monitoring, testing, analysis,

prediction, maintenance). Finally, the output data

produced as a result of the processes done by the

Digital Twin must be sent to the physical system for

which it realizes a replica. For this reason, data

exchange must be considered an important part of a

Digital Twin; without data exchange, most of

functions of a Digital Twin could not be realized (Qi,

2018). Interoperability of the data exchange seems a

Cavalieri, S. and Gambadoro, S.

Enhancing Interoperability of Digital Twins Based on Digital Twins Deﬁnition Language.

DOI: 10.5220/0011981000003467

In Proceedings of the 25th International Conference on Enterprise Information Systems (ICEIS 2023) - Volume 1, pages 741-748

ISBN: 978-989-758-648-4; ISSN: 2184-4992

 2023 by SCITEPRESS – Science and Technology Publications, Lda. Under CC license (CC BY-NC-ND 4.0)

741

very important requirement, allowing a Digital Twin

to communicate with a multitude of physical systems

and applications.

Interoperability between applications is

considered one of the main goals of Industry 4.0

(Liao, Ramos, et ali. 2017; Liao, Deschamps, et ali.

2017; Lelli, 2019). Open Platform Communications

Unified Architecture (OPC UA), is considered one of

the main reference standards for an interoperable

exchange of information between applications inside

Industry 4.0 (Ladegourdie, 2022; Ferrari, 2018;

González, 2019). The OPC UA is based on two

communication models: client/server and

publish/subscribe; a comprehensive information

model allows to represent data and the relevant

semantics.

The idea behind the paper is to enhance the

interoperability of a Digital Twin through integration

into the OPC UA domain. Figure 1 shows a Digital

Twin exchanging data with the real system it models,

and with applications using the DT. Data exchange

with applications based on OPC UA communication

system may be enabled through a solution able to map

the entire set of information maintained by a Digital

Twin into the OPC UA domain. Mapping should

include every semantic aspect of the Digital Twin, in

order to really enable an interoperable data exchange

between the two domains. The proposal presented in

this paper is based on the definition of a custom OPC

UA information model able to realize this mapping.

Figure 1 shows only an example of interoperability;

in this example, the information model of the OPC

UA Server shown by Figure 1, is able to represent

each element of the Digital Twin in the OPC UA

domain, making available the Digital Twin and its

relevant content to whatever application based on

OPC UA client role. The mapping solution here

presented enables a Digital Twin to have a

counterpart in the OPC UA domain; each information

(including semantic) maintained in a Digital Twin can

be accessed by a plethora of OPC UA-compliant

applications.

Figure 1: Graphical representation of the proposal.

Among the available Digital Twins, the Digital

Twin Definition Language model will be considered

in this proposal. The definition of a custom data

structures in the OPC UA information model, able to

represent each element of the original DTDL-based

Digital Twin, will be introduced in this work. The

proposed mapping has been implemented in order to

be validated; the relevant implementation and

validation will be introduced in the paper.

2 RELATED WORK

Current literature provides a lot of publications about

the use of OPC UA information model to structure

and expose data coming from different domains of

interest in order to achieve fully interoperability.

Considering mapping between Digital Twin and

OPC UA, several proposals are also present in the

current literature. Mapping of AAS to OPC UA is

proposed by (Cavalieri, 2020). Another example of

integration of AAS with OPC UA is given by (Arm,

2021). Integration of AAS and OPC UA is also

subject of the official specifications (Plattform

Industrie 4.0, 2020; OPC 30270, 2023), which define

an OPC UA model to expose AAS information to

OPC UA applications.

To the best of authors’ knowledge, considering

the integration of DTDL with OPC UA, only the

software solution, called OPCUA2DTDL

(OPCUA2DTDL, 2023), is currently available. This

solution aims to convert an OPC UA information

model into DTDL constructs; a DTDL digital model

can be built starting from its definition based on OPC

UA specification. The main limit of this solution is

that mapping in the opposite direction is not allowed.

In other terms, given an already defined DTDL-based

Digital Twin is not possible to achieve its counterpart

in the OPC UA domain. Introduction pointed out that

the paper has this aim, proposing an integration able

to map a Digital Twin realised by DTDL into OPC

UA information model. This is a very important

consideration which allows to point out the originality

of the proposed solution made in this paper.

3 OPC UA INFORMATION

MODEL

The OPC UA provides a semantically enriched

information model in order to represent data. The

OPC UA Information Model allows a server to

expose information to clients; publish/subscribe

Data from

real system

Applications

using DT

Digital Twin

OPC UA domain

OPC UA

Server

Client

OPC UA

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communication model is based on the same

information model used for the client/server

communication model.

The OPC UA Information Model is organized by

OPC UA Nodes grouped together to compose the so-

called OPC UA AddressSpace (Mahnke, 2009; OPC

Unified Architecture Part 3, 2023; OPC Unified

Architecture Part 5, 2023).

Each OPC UA Node belongs to a class named

NodeClass. In (OPC Unified Architecture Part 3,

2023; OPC Unified Architecture Part 5, 2023) it is

possible to have detailed information about the OPC

UA NodeClasses.

OPC UA defines standard graphical

representation for OPC UA NodeClasses. The reader

should refer to Annex C of (OPC Unified

Architecture Part 3) to have a complete description of

this representation, which will be used in this paper.

4 DTDL

The Digital Twins Definition Language (DTDL)

(DTDL, 2023) is a formalism capable of describing

Digital Twin devices and assets. DTDL uses JSON-

LD (JSON-LD, 2023).

According to DTDL, the structure and behaviour

of a Digital Twin is fully described by six classes of

metamodels: Interface, Telemetry, Property, Control,

Relationship and Component.

Every resource is modelled by an interface which

can contain a set of telemetry, properties, commands,

relationship and components. Telemetry describes

data emitted by a resource, whether it is a regular

stream of sensor readings or a calculated data stream;

Telemetry does not store any data.

Properties define values within a Digital Twin;

these values can be read-only or have read and write

states. Properties have a backing storage.

Commands correspond to functions that can be

invoked with optional input and output parameters.

Relationship describes a link to another digital twin

and makes it possible to create graphs of digital twins.

Component models the entities that exist in the DT,

including sensors, gateways, and digital systems.

5 MAPPING DTDL TO OPC UA

As it was pointed out in Section 2, literature provides a

lot of publications featuring the use of OPC UA

Information Model to structure and expose information

coming from different domains of interest. The reader

may refer to (Cavalieri, Salafia, 2020) to have an

overview of the common practices adopted when OPC

UA Information Model is used to model a generic

system. In this proposal, these common practices have

been taken into account to map the DTDL metamodel

classes into OPC UA Information Model; in particular,

custom OPC UA types have been defined through an

extension of the current OPC UA Information Model,

able to represents the DTDL metamodel classes and the

relevant properties.

The following subsections will present the

mapping of the six DTDL metamodels classes,

introducing the custom OPC UA types defined to

realize the proposal.

5.1 Interface

It has been assumed to map the Interface class with a

custom OPC UA ObjectType, called

DTDLInterfaceType. Some of the attributes of this

type were used to represent a subset of the properties

of the Interface class. Other properties of Interface

class were mapped using OPC UA Nodes connected

to the OPC UA DTDLInterfaceType ObjectType, as

shown by Figure 2.

Figure 2: OPC UA DTDLInterfaceType.

Among the DTDL properties of the Interface class

there is the property “contents”, which allows to

define a set of objects representing the contents of an

Interface; these objects belong to the other DTDL

classes (i.e., telemetry, properties, commands,

relationship and components). In order to map this set

Enhancing Interoperability of Digital Twins Based on Digital Twins Deﬁnition Language

743

of objects, a particular folder (named Contents in

Figure 2) is used. It contains several other folders (i.e.

Telemetries, Properties, Commands, Relationships

and Components), each of which organizes the OPC

UA Nodes used to represent the other DTDL classes;

the relevant mappings will be described in the

following subsections.

Another DTDL property is called “schemas”; it

represents the set of reusable data types which are

used in a digital twin interface. In OPC UA the

DataType NodeClass may be used to define the

representation of the DTDL data types. The OPC UA

FolderType Object called Schemas, shown in Figure

2, has been used to organize the OPC UA Property

Nodes, each containing the description of the OPC

UA DataType mapping the DTDL schemas featured

by the current interface.

Another folder present in Figure 2 is the Extends

FolderType Object. It maps the “extends” property of

the Interface Class. In DTDL, Interfaces can inherit

from multiple interfaces; for this reason, the DTDL

“extends” property is used to maintain details of the

set of interfaces each interface inherits from. As

shown by Figure 2, the use of a particular reference,

called HasAddIn, allows the Extends folder to point

to the DTDLInterfaceType Objects modelling the

DTDL Interfaces the current interface inherits from.

5.2 Telemetry

The metamodel class Telemetry describes the data

emitted by any digital twin. Telemetry does not store

any data.

Due to the lack of data stored by a DTDL

Telemetry element, it has been assumed to map it

with a custom OPC UA ObjectType, called

DTDLTelemetryType. Some of its basic attributes

were used to represent a subset of the properties of the

DTDL Telemetry class. Other properties were

mapped by OPC UA Nodes as shown by Figure 3.

As it can be seen, the DTDLTelemetryType

ObjectType has two optional properties, Comment

and Unit, mapping the Telemetry Class properties

“comment” (which allows to define a comment for

model authors) and “unit” (which defines a semantic

type of the Telemetry), respectively.

The DTDL “schema” property represents the data

type of the Telemetry; OPC UA DataType seems

suitable to represent this property, as said before. In

other to have a mapping from DTDL to OPC UA

domain, the OPC UA Property Node, called Schema

in Figure 3, is considered; it contains the description

of the OPC UA DataType mapping the DTDL

schemas featured by the current property.

Figure 3: OPC UA DTDLTelemetryType.

5.3 Property

The metamodel class Property allows to store values

within a digital twin. These values can be read-only

or have read and write states. For example, a device

serial number may be a read-only value that can be

read at any time; the desired temperature on a

thermostat may be a read-write value that can be

updated.

As DTDL Property class is used to store values, it

seems that it may be represented very well by the

OPC UA DataVariable Node. For this reason, it has

been assumed to map the DTDL Property class with

a custom OPC UA DataVariableType, called

DTDLPropertyType. Some of the basic attribute of

the DTDLPropertyType were used to represent

properties of the Property class. Other properties have

been mapped as shown by Figure 4. The

DTDLPropertyType VariableType features two

optional properties, Comment and Unit, mapping the

DTDL Property class properties “comment” and

“unit”, respectively.

Figure 4: OPC UA DTDLPropertyType.

It is important to point out that the proposed

modelling of DTDL Property class with the custom

DTDLPropertyType DataVariableType, allows to

make available the OPC UA attribute Value, which

may be used to contain the real value of the digital twin.

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5.4 Command

The metamodel class DTDL Command allows to

describe a function or operation that can be performed

on digital twins.

It was assumed to represent the Command class

through a custom OPC UA ObjectType, called

DTDLCommandType, featuring the structure shown

by Figure 5.

Figure 5: OPC UA DTDLCommandType.

As shown, the DTDLCommandType ObjectType

features a property and a method. The property called

Comment models the DTDL “comment” property of

the DTDL Command class. The OPC UA method

called Command represents the function/operation

modelled by the DTDL Command class; it features

optional input and output parameters (called Request

and Response, respectively).

5.5 Relationship

The metamodel class DTDL Relationship describes a

link to another (separate) digital twin and enables

graphs of digital twins to be created.

As done for other DTDL metamodel classes, this

class has been mapped using an OPC UA

ObjectType. A custom ObjectType has been defined

and called DTDLRelationshipType, shown by Figure

6. In particular, it features the three properties

Comment, MinMultiplicity and MaxMultiplicity.

They model the DTDL properties “comment”,

“minMultiplicity” and “maxMultiplicity”,

respectively.

The DTDL property named “properties”

represents the set of elements of Property class that

define relationship-specific state. In order to represent

this set, a folder has been considered in OPC UA; in

the Figure 6 it is called Properties. This folder will

contain OPC UA Nodes each modelling an element

of Property class, using OPC UA Property Nodes

belonging to DTDLPropertyType.

Figure 6: OPC UA DTDLRelationshipType.

The last DTDL property to be mapped is the

“target”, representing the link to a metamodel class

Interface. In OPC UA links between Nodes are

realized using References; for this reason, the DTDL

“target” was mapped into OPC UA through a

Reference pointing to the OPC UA Node modelling

the Interface to which the Relationship refers. A

custom Reference, called DTDLHasTarget has been

defined.

5.6 Component

The metamodel class Component enables interfaces

to be composed of other interfaces.

A custom OPC UA ObjectType called

DTDLComponentType has been defined, as shown

by Figure 7.

Figure 7: OPC UA DTDLComponentType.

It has an optional property called Comment,

modelling the DTDL property “comment”. The other

Enhancing Interoperability of Digital Twins Based on Digital Twins Deﬁnition Language

745

DTDL property to be mapped is the “schema”, which

defines the DTDL Interface of the component. As the

DTDL Interface has been modelled in OPC UA by an

Object of DTDLInterfaceType type, Figure 7 shows

the presence of a mandatory Object of this type. In

order to allow the DTDLComponentType Object to

point to the DTDLInterfaceType Object, a custom

Reference has been defined called DTDLHasSchema,

as shown by the Figure 7.

6 IMPLEMENTATION

The custom OPC UA Information Model presented in

the previous section has been implemented by the

authors and the software implementation is freely

available at the GitHub repository (DTDL-OPCUA-

Information-Models-Mapping, 2023).

7 CASE STUDY

Using the software implementation, the proposal has

been validated considering several case studies. In the

following subsections details about the different steps

followed in the validation procedure will be given.

Details will refer to a very simple scenario,

considered in order to be easily read and understood.

It has been assumed to take into consideration a

Digital Twin of a building. In particular, a basic

model of a room has been defined and its extension to

a meeting room has been considered. Figure 8 shows

the description of the DT model called “Room”,

modelling a room; the model is made up by the DTDL

Interface “Room” featuring only one Property (i.e.

“setlight”).

Figure 8: DTDL model of a room.

Another DTDL model has been considered, called

“MeetingRoom”; it models a meeting room and

includes all the properties of the “Room” model,

adding other ones. As shown by Figure 9, the DTDL

Interface called “MeetingRoom” features a contents

property made up by two Property elements (i.e.,

“occupied” and “tempValue”). This interface extends

the simpler interface called “Room”.

Figure 9: DTDL model of a meeting room.

7.1 Digital Twin in Azure Platform

The DTDL model “MeetingRoom” shown by Figure

9 was implemented inside Microsoft Azure Digital

Twin platform available at (Microsoft Azure, 2023).

A particular tool named “Azure Digital Twin

Explorer” is available in this platform to import

DTDL models and to create instance of Digital Twins

based on DTDL. The “Room” and “MeetingRoom”

DTDL models were uploaded in this tool, and a single

instance of the “MeetingRoom” Interface has been

created; the instance was named “MeetingRoomA”.

7.2 OPC UA Server

The next step of the proposed mapping is the

definition of an OPC UA Server able to map each

Digital Twin instance into the OPC UA Information

Model. In our simple case study, the Digital Twin

instance is the “MeetingRoomA”.

OPC UA Server was implemented in NodeJS

using the NodeOPCUA (NodeOPCUA, 2023), which

is an OPC UA SDK making available the OPC UA

communication stack written in TypeScript for

NodeJS.

According to the mapping solution presented in

Section 5, the OPC UA AdressSpace mapping the

“MeetingRoomA” instance may be achieved, as

shown by Figure 10. The OPC UA Object

{

"@id": "dtmi:example:Room;1",

"@type": "Interface",

"@context": "dtmi:dtdl:context;2",

"displayName": "Room",

"contents": [

{

"@type": "Property",

"name": "setlight",

"schema": "boolean",

"writable": true

}

]

}

{

"@id": "dtmi:example:MeetingRoom;1",

"@type": "Interface",

"@context": "dtmi:dtdl:context;2",

"extends": [ "dtmi:example:Room;1" ],

"displayName": "MeetingRoom",

"contents": [

{

"@type": "Property",

"name": "occupied",

"schema": "boolean",

"writable": true

{

"@type": "Property",

"name": "tempValue",

"schema": "double",

"writable": true

}

]

}

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“MeetingRoomA” is an instance of the

DTDLInterfaceType ObjectType. It features the

folder Contents, containing the folder Properties,

which organizes two OPC UA DataVariable Nodes

instances of the DTDLPropertyType type. They

model the two DTDL properties “occupied” and

“tempValue”, shown by Figure 9. Figure 10 points

out the main attributes of these Objects. The OPC UA

Object “MeetingRoomA” features another

component made up by the mandatory folder

Extends; the HasAddIn reference allows this folder to

point to the DTDLInterfaceType Object modelling the

DTDL Interfaces the current interface inherits from, i.e.

the Interface named “Room”. This interface is

modelled by the OPC UA DTDLInterfaceType

Object “Room”, featuring one OPC UA DataVariable

Node organized by the Properties folder. This Node

represents the DTDL property named “setlight”

shown in Figure 8.

Figure 10: Mapping the instance of the meeting room model

using the OPC UA DTDL InterfaceType.

The OPC UA AddressSpace shown by Figure 10

was implemented using the UaModeler (UaModeler,

2023) tool. Figure 11 shows the graphical

representations of the OPC UA Nodes that have been

created using the UaModeler tool.

Figure 11: OPC UA Nodes created for this case study.

Data values maintained by a Digital Twin instance

changes over the time due to updates of the real

system for which the Digital Twin realizes a digital

replica. It is clear that information maintained by the

Digital Twin instance and by the OPC UA Server

must be consistent. This means that each change in a

property of the Digital Twin instance must be updated

into the OPC UA Server, and vice versa. For this

reason, a custom program was implemented inside

the server in order that each time an information

changes inside the Digital Twin instance, the same

change must be reflected in the OPC UA Server, and

vice versa. This code has been developed in NodeJS,

as said; the Azure SDK for NodeJS (azure-sdk-for-js,

2023) has been also used; this software realizes the

communication stack needed by a NodeJS program to

the access to the Digital Twin instances.

7.3 Validation

The last step followed in the validation procedure

adopted by the author was the execution of several

tests aimed to verify the consistency between

information maintained by Digital Twin instance and

OPC UA AddressSpace. Considering the simple case

study here presented, several changes in the

properties of the DT instance “MeetingRoomA” were

performed, verifying that the consistent changes

occurred in the OPC UA Server, accessing the

information by OPC UA client applications.

Enhancing Interoperability of Digital Twins Based on Digital Twins Deﬁnition Language

747

8 CONCLUSIONS

The paper has introduced a solution of mapping from

DTDL to OPC UA Information Model. The proposal

allows to enable interoperability from DTDL-based

Digital Twins and OPC UA. The article is original as

the issue has not been dealt with so far. The

implementation of the mapping here proposed, has

been done by the authors in order to demonstrate the

feasibility of the proposed solution.

REFERENCES

azure-sdk-for-js (2023). Available online: https://github.

com/Azure/azure-sdk-for-js/tree/%40azure/digital-

twins-core_1.1.0/sdk (accessed on 24 February 2023).

Arm, J., Benesl, T., Marcon, P., Bradac, Z., Schröder, T.,

Belyaev, A., Werner, T., Braun, V., Kamensky, P.,

Zezulka, F., Diedrich, C., Dohnal, P. (2021).

Automated Design and Integration of Asset

Administration Shells in Components of Industry 4.0.

Sensors, 21(6), 2004.

Cavalieri, S., Salafia, M.G. (2020) Insights into Mapping

Solutions Based on OPC UA Information Model

Applied to the Industry 4.0 Asset Administration Shell.

Computers, 9, 28.

DTDL (2023). Digital Twins Definition Language.

Available online: https://github.com/Azure/opendigital

twins-dtdl/blob/master/DTDL/v2/dtdlv2.md (accessed

on 24 February 2023).

DTDL-OPCUA-Information-Models-Mapping (2023).

Available online: https://github.com/OPCUAUniCT/

DTDL-OPCUA-Information-Models-Mapping

(accessed on 24 February 2023).

Ferrari, P., Flammini, A., Rinaldi, S., Sisinni, E., Maffei,

D., Malara, M. (2018). Impact of Quality of Service on

Cloud Based Industrial IoT Applications with OPC UA.

Electronics, 7(7), 109.

González, I., Calderón, A.J., Figueiredo, J., Sousa, J.M.C.

(2019). A Literature Survey on Open Platform

Communications (OPC) Applied to Advanced

Industrial Environments. Electronics, 8(5), 510.

Jacoby, M., Usländer, T. (2020). Digital Twin and Internet

of Things—Current Standards Landscape. Applied

Sciences, 10(18), 6519.

JSON-LD 1.1-A JSON-based Serialization for Linked

Data. Available online: https://www.w3.org/TR/json-

ld11/ (accessed on 24 February 2023).

Ladegourdie, M., Kua, J. (2022). Performance Analysis of

OPC UA for Industrial Interoperability towards

Industry 4.0. IoT, 3(4), 507–525.

Lelli, F. (2019). Interoperability of the Time of Industry 4.0

and the Internet of Things. Future Internet, 11(2), 36.

Liao, Y., Deschamps, F., Loures, E.F.R., Ramos, L.F.P.

(2017). Past, present and future of Industry 4.0 - a

systematic literature review and research agenda

proposal, International Journal of Production Research,

55:12, 3609-3629

Liao, Y., Ramos, L.F.P., Saturno, M., Deschamps, F.,

Loures, E.F.R., Szejka, A.L. (2017) The Role of

Interoperability in The Fourth Industrial Revolution

Era,IFAC-PapersOnLine,50(1)12434-12439.

Mahnke, W., Leitner, S.H., Damm, M. (2009). OPC

Unified Architecture; Springer.

Microsoft Azure (2023). Available online: https://portal.

azure.com/#home (accessed on 24 February 2023).

Mihai, S., et al. (2022). Digital Twins: A Survey on

Enabling Technologies, Challenges, Trends and Future

Prospects. IEEE Communications Surveys and

Tutorials, 24(4), 2255-2291.

NodeOPCUA (2023). Available online: https://node-

opcua.github.io/ (accessed on 24 February 2023).

OPC 30270 (2023). OPC UA for I4 Asset Administration

Shell. Available online: https://opcfoundation.org/

developer-tools/documents/view/273 (accessed on 24

February 2023).

OPCUA2DTDL (2023). OPC UA to DTDL Conversion

Tool. Available online: https://github.com/khilscher/

OPCUA2DTDL (accessed on 24 February 2023).

OPC Foundation. OPC Unified Architecture Part 3:

Address Space Model. Available online: https://opc

foundation.org/developer-tools/documents/view/160

(accessed on 24 February 2023).

OPC Foundation. OPC Unified Architecture Part 5:

Information Model. Available online: https://opcfoun

dation.org/developer-tools/documents/view/162

(accessed on 24 February 2023).

Plattform Industrie 4.0 (2020), ZVEI. Details of the Asset

Administration Shell—Part 1. Available online:

https://www.zvei.org/en/press-

media/publications/details-of-the-asset-administration-

shell/ (accessed on 24 February 2023).

Pribiš, R., Beňo, L., Drahoš, P. (2021). Asset

Administration Shell Design Methodology Using

Embedded OPC Unified Architecture Server.

Electronics, 10(20), 2520.

Qi, Q., Tao, F. (2018). Digital twin and big data towards

smart manufacturing and industry 4.0: 360 degree

comparison. IEEE Access, 6, 3585–3593.

Rasheed, A., San, O., Kvamsdal, T. (2020). Digital Twin:

Values, Challenges and Enablers. IEEE Access 2020, 8,

21980–22012.

Rocha, H.d., Pereira, J., Abrishambaf, R., Espirito Santo, A.

(2022). An Interoperable Digital Twin with the IEEE

1451 Standards. Sensors, 22(19), 7590.

UaModeler (2023). Available online: https://documen

tation.unified-automation.com/uamodeler/1.3.0/html/

index.html (accessed on 24 February 2023).

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