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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Ontology-Driven eMobility Booking Management in the Energy Data Space</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Sarra Ben-Abbès</string-name>
          <email>benabbessarra@gmail.com</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Marion Arlès</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jean-Marc Rives</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>GIREVE</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>France</string-name>
        </contrib>
      </contrib-group>
      <abstract>
        <p>The Energy Data Space provides a collaborative framework for data sharing and management, ofering a promising foundation for advancing electromobility services. This paper examines the role of semantic interoperability within the Energy Data Space to enhance eMobility booking management. We propose a domain-specific ontology tailored to standardize knowledge representation, facilitating seamless integration of booking platforms, Electric Vehicle charging infrastructure, tarifs, and user preferences. A structured methodology is presented for the design and construction of semantic data models, encompassing requirements analysis, ontology engineering, iterative validation with competency questions, and data-driven testing with real-world scenarios. The resulting ontology forms the backbone of a knowledge graph, supported by a scalable data ingestion workflow designed to harmonize and integrate heterogeneous datasets, enabling functionalities such as real-time reservations, tarif optimization, and personalized services. Practical use cases are explored to demonstrate the applicability of the ontology and knowledge graph, including multi-provider booking harmonization and charging station optimization. In addition, the paper reviews relevant standards and best practices to address implementation challenges and opportunities in leveraging semantic technologies within the Energy Data Space. Our findings highlight the transformative impact of semantic interoperability, structured methodologies, and knowledge graph technologies on the eficiency, accessibility, and sustainability of eMobility services. By adopting collaborative frameworks and semantic solutions, stakeholders can unlock the innovation and integration potential in the evolving electromobility ecosystem.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Ontology</kwd>
        <kwd>Semantic Interoperability</kwd>
        <kwd>eMobility</kwd>
        <kwd>Booking Management</kwd>
        <kwd>Energy Data Space</kwd>
        <kwd>Electric Vehicle Charging</kwd>
        <kwd>Semantic Data Ingestion</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        The transition towards electromobility represents a fundamental shift in transportation paradigms,
driven by imperatives for sustainability, energy eficiency, and environmental stewardship. Electric
vehicles (EVs) and their associated infrastructure promise to revolutionize urban mobility, ofering
cleaner, quieter, and more cost-efective alternatives to traditional combustion engine vehicles [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ].
However, the realization of this vision hinges not only on technological advancements but also on the
efective management of the vast amounts of data generated and exchanged within the electromobility
ecosystem [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ].
      </p>
      <p>
        A critical aspect of this transformation is semantic interoperability, which enables diverse systems,
platforms, and stakeholders to exchange, interpret, and utilize data seamlessly. In the context of
electromobility, semantic interoperability ensures smooth communication and collaboration among
vehicle manufacturers, charging infrastructure providers, energy utilities, policymakers, and end
users [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. This facilitates essential real-time services such as electric vehicle charging reservations,
tarif optimization, personalized user experiences, and the seamless integration of charging networks
between providers.
      </p>
      <p>Semantic interoperability relies on standardized vocabularies, ontologies, and data models. By
utilizing semantic technologies such as RDF (Resource Description Framework) and OWL (Web Ontology
Language), stakeholders can overcome interoperability barriers, enabling eficient data exchange across
heterogeneous platforms [4]. These technologies promote data reuse and integration, aligning with
the FAIR principles — Findable, Accessible, Interoperable, and Reusable [5]. However, while semantic
technologies significantly contribute to the interoperability and reusability aspects, they are not suficient
on their own to guarantee that data is truly findable and accessible, which also requires appropriate
data governance policies, persistent identifiers, and data publication infrastructures [ 6]. Furthermore,
knowledge management plays a pivotal role in this context. It involves the processes, tools, and
methodologies used to capture, organize, and leverage knowledge from diverse data sources. In the
energy data space, this includes the development of domain-specific ontologies, knowledge graphs, and
semantic annotations to provide valuable insights and support informed decision-making [7]. Through
semantic technologies, stakeholders can extract actionable intelligence from complex, fragmented data
landscapes, paving the way for improved planning, optimization, and policy-making.</p>
      <p>At the core of electromobility’s evolution is the rise of EVs, which promises significant environmental
and economic benefits, such as reducing greenhouse gas emissions and decreasing reliance on fossil
fuels. However, for electromobility to succeed, robust and interoperable charging infrastructure is
required to meet the growing global demand for EVs [8]. The widespread adoption of electromobility
will depend on overcoming various challenges, including range anxiety, infrastructure limitations, and
interoperability constraints.</p>
      <p>The Energy Data Space provides a collaborative framework for addressing these challenges. It
facilitates standardized data management and exchange, ofering a foundation for advancing electromobility
services. By leveraging semantic technologies, stakeholders can harmonize diverse datasets across the
electromobility ecosystem, enabling more eficient and reliable services.</p>
      <p>This paper explores the integration of semantic interoperability principles within the Energy Data
Space to address the unique challenges of electromobility. Specifically, we propose an electromobility
ontology designed to support electric vehicle charging booking services. This ontology is complemented
by a scalable knowledge graph and an agile methodology to design and build semantic data models.
This methodology, an extension of prior research, incorporates iterative validation with competency
questions, real-world scenario testing, and FAIR compliance, ensuring applicability in dynamic,
realworld contexts. Practical use cases, such as multi-provider booking harmonization and charging station
optimization, are examined to demonstrate the transformative potential of semantic technologies in
electromobility. The paper also addresses the broader implications of semantic interoperability, focusing
on its role in driving sustainability, accessibility, and innovation in the sector.</p>
      <p>The remainder of this paper is structured as follows. Section 2 provides an overview of the
foundational concepts and background relevant to semantic interoperability in electromobility. Section
3 introduces a motivating scenario to highlight the pressing need for eficient data exchange and
interoperability. Section 4 presents the requirements for interoperable booking services and outlines
our proposed methodology for semantic data model design, highlighting its FAIR compliance and
agile approach. Section 5 elaborates on the development and implementation of the Electromobility
Ontology and its associated knowledge graph. Section 6 details data ingestion workflows, federated
query processing, and decision-making applications within the Energy Data Space. Section 7 engages
in a critical discussion of the results and addresses the challenges and opportunities for future research.
Finally, Section 8 concludes the paper with reflections on the transformative potential of semantic
interoperability to advance electromobility and recommendations for future work.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Related Work</title>
      <p>Previous research has explored various aspects of electromobility and EV charging infrastructure.
Although existing studies have made significant contributions to the field, gaps remain in standardizing
knowledge representation and ensuring interoperability across diverse electromobility platforms. This
paper aims to bridge these gaps by proposing a novel ontology-driven approach to improve the eficiency
of EV charging booking services, focusing on improving data integration, decision-making, and user
experience.</p>
      <p>The intersection of semantic interoperability, knowledge management, and electromobility has
garnered significant attention from researchers, practitioners, and policy makers who seek to address
the complex challenges of sustainable transportation. This section reviews the existing literature and
research initiatives that have contributed to our understanding of these interconnected domains.</p>
      <p>Semantic interoperability has become a cornerstone of modern data management systems, enabling
seamless communication and collaboration between heterogeneous environments. Smith et al. [9]
emphasize the importance of semantic technologies, particularly ontologies and semantic web standards,
in facilitating data integration and knowledge sharing in smart transportation systems. Using ontologies,
linked data, and semantic models, systems can better interpret, exchange, and integrate data from
diverse sources, driving more efective decision-making processes and improving system performance.</p>
      <p>Further research by Garcia et al. [10] has focused on the challenges of semantic interoperability in the
context of electromobility, particularly in the integration of EV charging stations into broader smart city
ecosystems. They argue that developing a shared vocabulary and a set of standards for data exchange is
crucial to ensuring seamless communication between charging stations, vehicle management systems,
and user interfaces. They propose a set of semantic models to support these interactions and enhance
interoperability between public and private charging infrastructures.</p>
      <p>In the context of energy management, some studies have explored how integrating EV-related data
into broader energy grids can facilitate demand response and optimize energy usage. The European
Union-funded E-Mobility Observatory project (European Commission, 2021) aims to establish standards
for data exchange and interoperability in electromobility. This initiative, which includes collaboration
with industry leaders and government agencies, has worked to create open-source tools for harmonizing
data formats and protocols, which could be crucial for improving the interoperability of charging services
across diferent platforms. Garcia et al. [11] examine how interoperable booking services can influence
user adoption and satisfaction in electric vehicle sharing programs. Their study emphasizes that technical
interoperability—ensuring consistent data exchange across systems—is a necessary foundation, but
not suficient on its own. User-centric design plays an equally critical and complementary role in
ensuring adoption and usability. Designing intuitive interfaces and ensuring seamless user journeys are
crucial for bridging the gap between technical standards and actual user experience. Ontology-driven
approaches can support this balance by ofering structured, machine-readable representations of data
while also enabling flexible, personalized service configurations that meet user needs. In a similar
line, the work of Zheng et al. [12] focuses on the role of semantic web technologies in enhancing the
user experience of electric vehicle charging systems. They argue that by adopting semantic standards,
users could benefit from more accurate and personalized booking services that integrate with other
transportation modes, further improving the accessibility and convenience of electromobility solutions.</p>
      <p>Ontologies have been proposed as a solution to the challenges of standardizing EV charging data.
Several studies [13, 14] have explored how ontologies can provide a structured framework to represent
complex data on charging stations, connectors, vehicle types, and user preferences. These semantic
models can ensure a common understanding of key concepts between diferent systems and platforms,
facilitating data sharing and integration.</p>
      <p>Miller et al. [15] present an ontology for the electric vehicle charging infrastructure that includes
various categories of charging stations, such as public, private, fast and slow chargers, along with
detailed specifications on power ratings, connector types, and payment methods. This model is
designed to promote standardization in the way charging data is captured, stored, and exchanged,
allowing for more eficient and user-friendly booking systems.</p>
      <p>In addition to individual research eforts, collaborative initiatives have played an important
role in advancing knowledge and best practices for electromobility. The E-Mobility Observatory, for
example, serves as a key platform for the exchange of research findings and the development of policy
recommendations on the future of electromobility. Its focus on data harmonization, interoperability,
and open standards aligns with the goals of this paper, which advocates the use of ontologies to
streamline and standardize EV charging data exchanges.</p>
      <p>Furthermore, the work of the European Commission (2021) highlights the growing importance of
cross-sector collaborations in the electromobility ecosystem. Policies aimed at promoting interoperable
charging networks, including the standardization of data formats and protocols, are essential to foster a
sustainable and scalable transition to electromobility. These policy frameworks provide the regulatory
foundation needed for the widespread adoption of interoperability standards, as well as for ensuring
privacy, security, and governance in the exchange of energy and vehicle data. Despite the advancements
in knowledge management and semantic interoperability, several challenges remain. Privacy and
security concerns, particularly in the context of sensitive user data and payment systems, must be
addressed through robust encryption and governance mechanisms. Scalability also remains a critical
issue, as solutions need to be adaptable to diferent geographical regions and charging infrastructures,
each with varying technical standards and user needs. Additionally, while semantic technologies
provide a powerful tool for data integration, their application to real-time decision-making in dynamic
environments such as EV charging stations requires further research. Real-world implementations and
pilot projects are necessary to validate the efectiveness of ontology-driven solutions in improving EV
charging booking systems and ensuring seamless interoperability across platforms.
The literature on semantic interoperability, knowledge management, and electromobility
illustrates the importance of developing standardized frameworks and semantic models to address
the complexities of the EV ecosystem. While significant strides have been made, there is still a
need for comprehensive, ontology-driven approaches that can provide the necessary structure and
standardization for data exchange across diverse electromobility platforms. This paper contributes to
this ongoing conversation by proposing a novel approach to enhance the eficiency and scalability of
EV charging booking services, laying the foundation for future research and development in this area.</p>
    </sec>
    <sec id="sec-3">
      <title>3. Methodology for Semantic Data Model Design and Construction</title>
      <p>Developing ontologies is a complex and time-consuming task with no universally agreed-upon
methodology [16]. Various methodologies have been proposed, including Cyc [17], KACTUS [18],
METHONTOLOGY [19], and others [20, 21]. Each has its strengths, but none are universally superior, and the
choice often depends on the specific requirements. For the electromobility use case, we adapt the
methodologies of [20] and [21] to design a semantic data model. The methodology follows five steps, as
shown in Fig. 1:
1. Ontology Requirements Specification : Analyze use cases, collaborate with domain experts,
develop interaction models, define the ontology’s scope, formulate competency questions, and
identify relevant terms.
2. Ontology Analysis: Identify key concepts/relationships, reuse/extend existing ontologies, and
construct the ontology by structuring concepts and relationships.
3. Ontology Diagrams Design: Create visual diagrams to represent the ontology and collaborate
with stakeholders for validation and refinement.
4. Ontology Formalization: Ensure diagram consistency, formalize new modules for integration,
and align the ontology with existing models.
5. Ontology Population/Querying: Gather and integrate data to populate the ontology, generate
semantic data, store it in a triplestore (e.g., GraphDB), and implement SPARQL queries for data
retrieval.</p>
    </sec>
    <sec id="sec-4">
      <title>4. Motivating Scenario and Data Exchange Requirements</title>
      <p>In a bustling urban environment, electromobility is increasingly embraced, requiring eficient data
exchange to support services like vehicle charging, route planning, and fleet management.
Seamless data flow across heterogeneous systems demands well-defined data exchange requirements and
interoperability standards to ensure compatibility, scalability, and reliability.</p>
      <sec id="sec-4-1">
        <title>4.1. Scenario: Interoperable Booking in Electromobility</title>
        <p>A common challenge for electric vehicle users is the uncertainty of charging point availability. This
use case envisions a booking service where Electric Mobility Service Providers (eMSPs) enable users
to locate, reserve, and access charging points across multiple providers and national borders. The
scenario emphasizes semantic interoperability for enabling unified access to distributed data sources
and heterogeneous systems.</p>
      </sec>
      <sec id="sec-4-2">
        <title>4.2. Functional and Semantic Requirements</title>
        <p>To support this scenario, several functional and semantic data exchange requirements have been
identified. First, real-time availability synchronization (R1) is essential to ensure that systems can
exchange up-to-date status information—such as whether a charging station is occupied, reserved,
or available. Second, user identity and authentication exchange (R2) must be supported through
cross-provider mechanisms like OAuth2 or eIDAS to enable secure booking across diferent eMSPs.
Third, there is a need for unified service descriptions (R3), whereby charging stations and services are
semantically described—covering plug types, power levels, and pricing models—using shared ontologies
to facilitate automated discovery and reasoning.</p>
        <p>Fourth, cross-border interoperability (R4) must be achieved by ensuring that data exchange complies
with regional policies and standards, such as OCPI or ISO 15118, to guarantee service continuity across
countries. Fifth, booking lifecycle integration (R5) is required, meaning that systems should support
all stages of the booking process—including initiation, confirmation, cancellation, and updates—via
interoperable APIs and ontology alignment. Finally, user-centric service adaptation (R6) must be enabled
by semantically representing user preferences, such as preferred charging speed or payment method, to
ensure personalized service selection.</p>
      </sec>
      <sec id="sec-4-3">
        <title>4.3. Transferring Knowledge Graph</title>
        <p>Transferring knowledge graphs within the energy data space ofers opportunities for efective
knowledge exchange, but challenges such as data quality, consistency, and privacy must be addressed. By
adopting standardized ontologies, stakeholders can improve data integration and system compatibility.
Privacy concerns arise due to the inclusion of sensitive user data (e.g., identities, locations, usage
patterns) in booking services; to mitigate these, the system applies data minimization, anonymization
or pseudonymization techniques, role-based access control, and consent management aligned with
GDPR principles. These mechanisms ensure secure data handling and build user trust. The use of
standardized, privacy-aware knowledge graphs enhances interoperability and fosters a reliable and
seamless electromobility ecosystem.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>5. Building a Semantic Data Pipeline for Electromobility</title>
      <p>In this paper, we present the Semantic Data Pipeline developed for the booking use case in the Omega-X
project1, focusing on the semantic transformation, storage, and querying of data related to electric
vehicle (EV) charging services. The pipeline is designed to integrate real datasets and simulation datasets,
using electromobility ontology modules to structure and represent the domain’s data efectively. We
implemented this pipeline by leveraging the SPARQL-Generate tool2, an extension of the SPARQL
query language, to convert data into RDF graphs in a flexible and expressive manner. The RDF data is
stored in a GraphDB triplestore3 in Turtle format. This semantic data can be queried using SPARQL
and shared in JSON-LD format to facilitate smooth data exchange across diferent systems and services
in the broader data space. This semantic data pipeline (see Fig. 2) ofers a comprehensive, flexible, and
interoperable solution for managing and exchanging electromobility data in a standardized manner,
ensuring compatibility with multiple partners and systems in the sector.</p>
      <sec id="sec-5-1">
        <title>5.1. Electromobility Ontology Development</title>
        <p>The implementation of the Electromobility Ontology is pivotal to ensuring scalability, interoperability,
and extensibility within the electromobility ecosystem. Developed using standardized semantic web
technologies such as OWL and Protégé, the ontology facilitates seamless integration by providing a
shared, machine-interpretable vocabulary that aligns heterogeneous data formats and terminologies.
This standardization allows diferent EV charging booking systems to interpret and exchange data
consistently, regardless of their internal data structures or protocols.</p>
        <p>A structured approach was adopted for the ontology design, guided by key questions about its
purpose, scope, and application. This approach involves utilizing various resources such as IEC-62559</p>
        <sec id="sec-5-1-1">
          <title>1https://omega-x.eu/</title>
          <p>2https://ci.mines-stetienne.fr/sparql-generate/
3https://www.ontotext.com/telechargez-graphdb/
templates4, interactions with domain experts, OCPI standard5, and the eMIP Protocol6, among others.
These include: (1) What are the primary objectives of the ontology?, (2) What is the scope of the
ontology?, (3) Who are the end-users, and how will the ontology be applied?, (4) What information
should the ontology capture?, and (5) What competency questions should the ontology answer?. The
answers to these questions formed the foundation for constructing the semantic data model, ensuring
alignment with real-world applications and addressing the critical needs of the electromobility sector.
Ontology Design Principles: The ontology design process adhered to key principles, prioritizing
the reuse of existing ontologies where possible. First, existing ontologies were thoroughly analyzed to
ensure clarity in concept hierarchies, such as subsumption and part-whole relationships. New concepts
were added where existing ontologies proved insuficient, covering only a portion of the use case. In
cases where existing ontologies did not address specific requirements, new modules were developed
to cater to electromobility-specific use cases while maintaining interoperability within the broader
ecosystem.</p>
          <p>Ontology Components: The Electromobility Ontology (see Fig. 3) is structured into several key
modules, each addressing distinct aspects of the ecosystem. The first module, Physical concepts,
represents tangible entities like Pool, Station, EVSE (Electric Vehicle Supply Equipment), and Connector,
describing the physical components of EV charging infrastructure. The second module, Abstract
concepts, encompasses generic properties such as Payment, Authentication, Price, and Status, which are
foundational for electromobility applications and extendable to other domains. Finally, the
Applicationspecific concepts module focuses on use-case-specific entities like Booking and Charging session, enabling
eficient scheduling and management of charging operations.</p>
        </sec>
        <sec id="sec-5-1-2">
          <title>4https://syc-se.iec.ch/deliveries/iec-62559-use-cases/ 5https://github.com/ocpi/ocpi 6https://www.gireve.com/wp-content/uploads/2022/09/Gireve_Tech_eMIP-V0.7.4_ImplementationGuide_1.0.7_en.pdf</title>
          <p>Key Ontology Modules: Diferent modules are designed to structure and streamline knowledge in
the use case of electromobility, addressing specific needs such as managing charging infrastructure,
optimizing bookings, facilitating stakeholder coordination, and ensuring interoperability across systems.
• EV Charge Infrastructure module: Provides detailed information on charging stations,
including location, charger types, capacity, and technical specifications. This module supports accurate
decision-making and infrastructure management (see Fig. 4).
• EV Charging Booking module: Facilitates slot reservations, availability checks, booking
confirmations, and cancellations, optimizing the utilization of charging infrastructure (see Fig. 5).
• Player module: Defines stakeholders such as EV users, service providers, and regulatory bodies,
enhancing coordination and communication across the ecosystem such as charge point operator
(CPO), eMobilityServiceProvider (eMSP).
• Status module: Tracks the operational status of charging points, providing real-time updates on
availability, usage, and equipment conditions.
• Tarif Pricing module: Captures pricing models (e.g., time-based, energy-based,
subscriptionbased) and supports dynamic pricing strategies to ensure transparency and user satisfaction.
• Generic Property module: Includes common attributes shared across modules to ensure
consistency and reduce redundancy.
• Alignment module: Ensures compatibility and alignment with existing ontologies and standards.</p>
          <p>It incorporates mappings and relationships to other established ontologies, enabling broader
interoperability within the electromobility sector and beyond. This module plays a critical role
in ensuring that the developed ontology can integrate seamlessly with other systems and data
sources, promoting a unified approach to data management in electromobility.</p>
          <p>This modular approach to ontology development allows for scalable and flexible enhancements, ensuring
that the ontology can evolve with the growing and changing needs of the electromobility sector. By
addressing each aspect comprehensively, this ontology not only enhances data exchange and
interoperability but also significantly improves the user experience and operational eficiency of electromobility
services.</p>
          <p>Ontology Evaluation: The ontology was evaluated based on three key criteria: Completeness, which
ensured the coverage of all relevant domains and concepts; Consistency, confirming the absence of
contradictory relationships; and Alignment with Domain Requirements, ensuring the reflection of
real-world needs in electromobility. Feedback from business experts and performance benchmarks
validated the ontology’s practical utility in enhancing EV charging services.</p>
          <p>Competency Questions and SPARQL Queries: A set of competency questions was developed
to ensure the ontology captures essential electromobility aspects and supports practical applications.
SPARQL queries were created to retrieve information about charging stations, check slot availability
and manage bookings, monitor EVSE status and operational conditions, and analyze pricing models
and user preferences. These queries enable seamless data integration, enhancing interoperability and
supporting eficient decision-making. The ontology optimizes infrastructure management and improves
the user experience in electromobility services.</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>6. Evaluation and Validation</title>
      <p>This section evaluates the semantic ontology and data pipeline for modeling and querying EVSE data
from the Gireve database, ensuring logical soundness, completeness, and competency question support.</p>
      <sec id="sec-6-1">
        <title>6.1. Dataset Description</title>
        <p>The Gireve dataset includes data from 17,986 pools across France and Belgium, covering 18,064 charging
stations, 53,105 EVSEs, and 54,169 connectors. It contains key attributes such as pool locations, EVSE
configurations, authentication modes, payment methods, and tarifs. While the dataset was partially
harmonised according to Gireve’s internal data standards, it required further semantic alignment and
transformation within our pipeline to ensure full interoperability with the Omega-X Electromobility
Ontology and support seamless integration with other heterogeneous data sources.</p>
      </sec>
      <sec id="sec-6-2">
        <title>6.2. Ontology Design and Development</title>
        <p>The ontology represents the charging infrastructure with key classes such as
:ElectricVehicleChargingStationPool, :ElectricVehicleChargingStation, :EVSE,
:EVSEConnector, :AuthenticationMode, :PaymentMethod, and :TarifProperty , defining relationships like
:hasEVSE and :appliesTarif , as well as properties such as connectorFormat and powerRating. It was
implemented using Protégé, OWL 2, and SPARQL, with reasoning engines Pellet and HermiT ensuring
logical consistency.</p>
      </sec>
      <sec id="sec-6-3">
        <title>6.3. Ontology Validation and Evaluation</title>
        <p>The ontology was validated through competency questions (CQs), such as the total EVSEs per CPO,
supported authentication methods, and connector availability. Logical consistency was ensured using
Pellet, which confirmed there were no contradictory relationships or axioms. Additionally, the mapping
of Gireve data to ontology classes was validated, as shown in Table 6.3.</p>
        <p>Metric
Total Pools Mapped
Total Stations Mapped
Total EVSEs Mapped
Total Connectors Mapped
Consistency Errors</p>
        <p>Value
17,986
18,064
53,105
54,169</p>
        <p>0</p>
        <p>Ontology Validation Metrics
Query Performance SPARQL queries were eficiently executed on GraphDB with response times
under 0.2 seconds for datasets with over 50,000 entities.</p>
      </sec>
    </sec>
    <sec id="sec-7">
      <title>7. Discussion</title>
      <p>Semantic interoperability in electromobility ofers significant innovation potential. Common standards
and protocols unify data, advancing infrastructure, user services, and regulations. The Electromobility
Ontology plays a central role in data integration and insight extraction, though challenges like data
silos and technical interoperability remain. Overcoming these requires coordinated eforts, robust
technologies, and governance structures.</p>
      <p>An additional challenge is the accessibility of semantic technologies for stakeholders who may not
have expertise in ontology design or semantic data transformation. Although our pipeline demonstrates
successful integration with familiar datasets, applying it to external or unfamiliar data sources requires
mapping eforts and domain knowledge. Lowering the entry barrier through tools, templates, and
documentation is therefore essential for widespread adoption.</p>
    </sec>
    <sec id="sec-8">
      <title>8. Conclusion and Perspectives</title>
      <p>The development of the Electromobility Ontology represents a milestone in standardizing knowledge
representation within the electromobility sector. By providing a structured framework for organizing
and querying data, the ontology improves the eficiency of electric vehicle charging services and
supports informed decision-making across the ecosystem. This initiative demonstrates how semantic
technologies can address practical challenges and unlock new opportunities in the energy data domain.</p>
      <p>To ensure broader applicability, future work will explore the ease of use and adaptability of the
pipeline with third-party datasets and by users unfamiliar with semantic tools. This includes evaluating
its usability in realistic deployment scenarios and designing intuitive user interfaces to simplify data
integration and transformation.</p>
      <p>Future research will also expand the ontology’s scope to include emerging trends such as smart grid
integration and real-time data analytics. Enhancing scalability and performance to accommodate
growing datasets will be prioritized. Continued collaboration among industry, academia, and policymakers
is essential to maintain the ontology’s relevance and adoption.</p>
      <p>Leveraging semantic principles and advanced tools, stakeholders can foster collaboration, drive
innovation, and pave the way for a sustainable and resilient transportation system. A shared commitment
to innovation and inclusivity will be crucial in shaping the future of mobility.</p>
    </sec>
    <sec id="sec-9">
      <title>Acknowledgments</title>
      <sec id="sec-9-1">
        <title>This work was supported by the EU-funded OMEGA-X project, ID: 101069287.</title>
      </sec>
    </sec>
    <sec id="sec-10">
      <title>Declaration on Generative AI</title>
      <p>The authors did not use any Generative AI tools (as defined in ceur-ws.org/genai-tax.html) during the
writing of this paper. Only non-generative tools such as DeepL were used for translation assistance.
The authors reviewed all content manually and take full responsibility for the final version.
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