=Paper=
{{Paper
|id=Vol-3762/520
|storemode=property
|title=Empowering e-services through the Semantic Web
|pdfUrl=https://ceur-ws.org/Vol-3762/520.pdf
|volume=Vol-3762
|authors=Raffaella Maria Aracri,Dario Frisardi,Roberta Radini,Valerio Santarelli
|dblpUrl=https://dblp.org/rec/conf/ital-ia/AracriFRS24
}}
==Empowering e-services through the Semantic Web==
https://ceur-ws.org/Vol-3762/520.pdf
Empowering e-services through the Semantic Web
Raffaella Maria Aracri1,† , Dario Frisardi1,† , Roberta Radini1,*,† and Valerio Santarelli2,†
1
Italian National Institute of Statistics (ISTAT), Italy
2
OBDA Systems s.r.l., Italy
Abstract
This article illustrates how to enhance data interoperability among Public Administrations (PPAA) by
leveraging the publication of e-services based on Semantic Web (SW) technologies such as ontologies, controlled
vocabularies, and data schemas, which, through standard languages like OWL [6], RDF[12], and SPARQL [5],
ensure harmonization, integrability, and unique semantics for representing administrative data. Furthermore,
the potential benefits of implementing semantic e-services through Ontology-based Data Management (OBDM),
a data governance methodology that enables data services through ontologies, decoupling their implementation
from the physical data sources of PPAA, are discussed. Additionally, the advantages for PPAA of data
exchange through semantic e-services utilizing concepts published in the Schema platform, developed by the
National Data Catalog project funded through PNRR funds, will be highlighted in the presented use case.
Keywords
PPAA, PNRR, Semantic Web, e-service, ontology, controlled vocabulary, data schema, OBDM
1. Introduction provides semantic clarity to administrative data
through an extensive network of Ontologies, Con-
As part of the investment initiatives delineated trolled Vocabularies, and data schemas [7]. These
within the National Recovery and Resilience Plan are facilitated by standard languages such as OWL,
(PNRR), which is part of the Next Generation EU RDF, and SPARQL, ensuring harmonization, in-
(NGEU) program, a measure concerning the dig- tegrability, and a unified semantics to represent
ital transition of Public Administrations (PPAA) administrative data information.
in data management and interoperability has been The adoption of these standards ensures the acces-
designated referred to as the National Digital Data sibility, reusability, and inferential capacities across
Platform (PDND). This platform acts as the tool data originating from various sources, processes,
to centralize the authentication and authorization and domains. To fully realize the benefits of these
methods for data exchange among parties. There- technologies, data ideally should be accessible via
fore, PDND manages the authorization phase of ac- standard data access protocols, such as SPARQL
cessing the Application Program Interfaces (APIs), [5], the W3C’s reference language for querying RDF
while PPAA set up their automatic connectors to datasets and OWL ontologies. Among the solu-
make data accessible and interoperable, promot- tions to ensure adherence to these protocols is
ing their sharing among administrations, as well the Ontology-based Data Management (OBDM)
as between citizens and enterprises. Particularly, paradigm [8], which advocates for a virtual approach
this approach avoids citizens from having to pro- to data governance, and consequently, data access,
vide the same information multiple times to various through ontologies.
administrations. The rest of this paper is structured as follows. In
Additionally, investments aimed at enhancing Section 2, we will introduce Schema, the National
data interoperability within the PDND also encom- Data Catalog for semantic interoperability, and ex-
pass the development of Schema, the National Cat- plain how the semantic assets published therein can
alog of data for semantic interoperability, which assist PPAA in the implementation of semantic e-
services according to data schemas, leading to full
Ital-IA 2024: 4th National Conference on Artificial In- data interoperability. Section 3 will illustrate the po-
telligence, organized by CINI, May 29-30, 2024, Naples, tential benefits of implementing e-services through
Italy
*
OBDM, primarily by decoupling the service layer
Corresponding author.
† from the data layer. In Section 4, we will provide
These authors contributed equally.
$ aracri@istat.it (R. M. Aracri); dario.frisardi@istat.it
an example, through a use case, of the benefits
(D. Frisardi); radini@istat.it (R. Radini); guaranteed to individuals by data interoperability.
santarelli@obdasystems.com (V. Santarelli)
0009-0005-4399-7589 (D. Frisardi)
© 2024 Copyright for this paper by its authors. Use permitted under
Creative Commons License Attribution 4.0 International (CC BY
4.0).
CEUR
ceur-ws.org
Workshop ISSN 1613-0073
Proceedings
2. Schema and the semantic Person :
type : o b j e c t
e-services d e s c r i p t i o n : h t t p s : / / w3id . o r g /
Within the framework of semantic interoperability i t a l i a / onto /CPV/ Person
enhancement, as delineated and overseen by the x−j s o n l d −c o n t e x t :
National Data Catalog (NDC) project [7], the de- ...
velopment of the portal, Schema, aims to make tax_code : h t t p s : / / w3id . o r g / i t a l i a /
the semantic resources of PPAA available. Schema onto /CPV/ taxCode
catalogs semantic assets, such as ontologies, con- d a t e _ o f _ b i r t h : h t t p s : / / w3id . o r g /
trolled vocabularies, and data schemas, making i t a l i a / onto /CPV/ d a t e O f B i r t h
them searchable, reusable, and thus fostering in- family_name : h t t p s : / / w3id . o r g /
teroperability. The semantic structures of Schema i t a l i a / onto /CPV/ familyName
enable the definition of a unified semantics that ...
harmonizes data representation and facilitates in- properties :
formation exchange for Italian PPAA. For further tax_code :
information about Schema and the available seman- $ r e f : "#/components / schemas /
tic assets, additional online resources can be found TaxCode "
in Appendix A. date_of_birth :
By leveraging ontology semantics, coherence and format : d a t e
consistency in data are ensured, significantly en- type : s t r i n g
hancing interoperability. Within ontologies, there is pattern :
uniformity in the description and referencing of en- [0 −9]{4} −[0 −1][0 −9] −[0 −3][0 −9]
tities present, supported by cardinality constraints family_name :
that govern the relationships among them. type : s t r i n g
Data schemas become an essential tool for PPAA ...
to expose their data and facilitate communication TaxCode :
through shared channels, exploiting the fundamen- type : s t r i n g
tal principle of a unified semantics. The strength of d e s c r i p t i o n : h t t p s : / / w3id . o r g /
data schemas lies in their ability to expose the data i t a l i a / onto /CPV/ taxCode
structure and enforce type and format constraints, ...
ensuring not only syntactic but also semantic inter- where the type is reported, as well as the URI
operability, targeting entities and concepts defined pointing to the semantic resource is included in
within ontologies and controlled vocabularies [10]. description. All the properties, whether re-
In the context of e-services, the accurate defini- quired or necessary for the service, are inserted
tion of data schemas plays a fundamental role in after specifying the corresponding semantic refer-
ensuring data coherence and complete interoper- ence. Thus, it can be observed how data schemas
ability. Establishing a shared ontological semantics, incorporate format and type constraints, as well
therefore, becomes crucial to guarantee a uniform in- as references to other components (e.g., tax_code),
terpretation of data by all involved parties. Through which will then reference a semantic resource defin-
a proper implementation of data schemas, e-services ing its concept. Currently, JSON-LD standard [13]
become essential tools for promoting the effective does not allow to define in a unique way the con-
utilization of semantic technologies within the realm text for primitive values, i.e. string, and in such
of public administration. cases it is necessary to adopt an ad-hoc shared strat-
The data schema format for the e-service must egy. More detailed data schemas are available in
adhere to the specifications of a YAML file [2] (if Appendix A.
version 3.0 of OpenAPI is utilized, the YAML file
should be named with an extension oas3.yaml).
Within the e-service data schema, the main com- 3. Implementation of e-services
ponents of the service in question must be defined,
taking into account the semantic references of on-
with OBDM
tologies and controlled vocabularies. An example The Ontology-based Data Management (OBDM)
of how the data schema should be structured to [4, 8, 9] is a paradigm introduced and promoted by
define the concept of “Person” is provided below, the Department of Computer, Control, and Man-
showcasing some of the key commands: agement Engineering “Antonio Ruberti” (DIAG) at
Sapienza University of Rome and by OBDA Sys- with mappings serving the role of reconciliation be-
tems1 . Its aim is the integration and governance of tween these levels. In this scenario, the ontology
data stored in an organization’s information system and corresponding mappings to the sources provide
through an ontology. The purpose of this approach not only a tool for data access but also a common
is to create a single conceptual access point to the basis for documenting an enterprise’s information
organization’s information assets, enabling the con- assets. This approach brings significant benefits
ceptual realization of all data governance services for governance and management of the information
within a complex system. system.
Indeed, OBDM can be viewed as a form of virtual E-services represent an opportunity to leverage
data integration. However, it is based on the notion the wealth of shared ontological models and con-
of replacing the global schema, which represents the trolled vocabularies in Schema, not only as tools for
unified view of the domain, with a conceptual and conceptual sharing, but also as a means of semanti-
formal representation formulated through an ontol- cally accessing data according to standardized and
ogy expressed in a logical language. This choice en- shared models. The value added by implementing
sures that the integrated view offered by an OBDM e-services through OBDM techniques is two-fold.
system is not limited to a structure accommodating Firstly, it resides in the capability to decouple
data from sources but constitutes a semantically the implementation of e-services from the physical
rich description of the relevant concepts within the sources of repositories that host the data of PPAA.
domain of interest and the relationships between In this scenario, the realization of e-services could
them. Similarly to how it occurs in data integra- potentially be accomplished solely through the artic-
tion systems, conceptual relationships, or mappings, ulation of requirements or queries on the ontological
are utilized to establish semantic correspondences models published on Schema by the data-owning
between the global schema and the data in the PPAA. This approach delegates the task of medi-
sources. ating with the data structures of individual PPAA
When seeking information, a query is expressed to the mappings, while the ontological reasoning
on the ontology (rather than on the information engine is entrusted with leveraging ontologies and
system’s databases), and the correspondences estab- mappings to translate the ontological requirement
lished between the data and the ontology’s concepts into queries on the physical data.
enable the ontological reasoning engine [11, 3] to Secondly, OBDM provide the possibility to ac-
derive the response. This relieves the user from the cess data using SPARQL [5], the W3C standard
necessity of understanding the technical aspects of language for querying ontologies and RDF datasets,
data storage and the specifics of where and how without the implementation of data transformation
data is storage. Similarly, when carrying out a and migration processes from their sources, typi-
data governance task (such as quality assessment, cally consisting relational DBMS, to triple stores
re-engineering, data cleaning, etc.), direct access for formatted RDF data. Given the complexity and
to the informational sources is bypassed, and the the volume of such data commonly managed by
appropriate functions are performed through the the information systems of PPAA, such processes
domain ontology. naturally require significant efforts, including infras-
The latter aspect not only formally describes the tructural ones. OBDM, on the other hand, offers
enterprise’s information model but also serves as a a solution distinct from this scenario, favoring a
means to embrace a declarative approach to data virtual approach to data access, where queries ex-
governance. Through the explicit delineation of pressed in SPARQL on the ontology are transformed
the domain representation, knowledge reusability into SQL queries on the physical sources at query
is achieved, a feat not achieved when the global time.
schema merely provides a unified description of the The decision to employ OBDM presents clear
underlying sources. advantages both in terms of e-service implementa-
OBDM systems generally have a common struc- tion, utilizing standard Semantic Web languages for
ture divided into three layers or tiers: ontology, map- querying ontologies, i.e. SPARQL, and in terms of
pings, and data sources. The distinction between their maintenance and evolution.
ontology and data sources reflects the separation The decoupling from the physical layer would
between the conceptual or semantic level, which allow isolating the e-service layer from the usual dy-
is presented to users, and the logical and physical namics of reorganization, restructuring, distribution,
level of the information system, stored in the sources, or replication typically encountered by databases
in information systems, particularly in the case of
1
www.obdasystems.com large organizations. In light of these developments,
adjustments to ensure the consistency of data shar- i. an e-service, S1, exposed by the National
ing services would be confined to the mapping layer, Register of the Resident Population (ANPR)
thus modifying the assertions that express the cor- system, which returns a confirmation if the
respondences between elements of the data layer person’s current municipality of residence
and those of the semantic layer. matches that of the cultural asset;
ii. an e-service, S2, provided by the Ministry
for Universities and Research (MUR), con-
4. A use case of semantic firming that the person is a student enrolled
interoperability in a High-Level Education course.
Based on what has been introduced in the previous The e-service S12, after retrieving the validations
sections, we aim to introduce an illustrative use case returned by the e-services S1 and S2, returns to
of data interoperability among PPAA and a valuable the requesting institution the authorization for the
aid to citizens by implementing the principle of once promotion for the individual.
only [1]. It can be hypothesized that the Ministry of An example of the YAML code configuration for
Culture, MiC, intends to offer a promotional service the e-service S1 is provided below, with the key
for the enjoyment of cultural assets (such as certain commands:
museums) by high-level education students from the components :
local area, i.e., their municipality of residence. schemas :
This use case involves an exchange of informa- RegisteredResidentPerson :
tion between e-services exposed by the relevant x−j s o n l d −c o n t e x t :
PPAA. For its modeling, as introduced in Section 2, RPO: h t t p s : / / w3id . o r g / i t a l i a /
a portion of the Schema semantic network is uti- onto /RPO/
lized, particularly the core Location (CLV), People tax_code : h t t p s : / / w3id . o r g /
(CPV), and Organization (COV) ontologies, along i t a l i a / onto /CPV/ taxCode
with domain-specific ontologies, such as the Italian currently_registered_residence :
Learning Ontology (Learning), Resident Population " @id " : "RPO:
Ontology (RPO), and the Cultural Heritage Ontol- currentlyHasRegistered
ogy (CulturalHeritage). All the reported ontologies ResidenceIn "
are available in Appendix A, while in Figure 1 there " @context " :
is a portion of the semantic network. " @base " : " h t t p s : / / w3id . o r g /
i t a l i a / controlled −
vocabulary / t e r r i t o r i a l −
classifications/cities "
type : o b j e c t
d e s c r i p t i o n : h t t p s : / / w3id . o r g /
i t a l i a / onto /RPO/
RegisteredResidentPerson
required :
− tax_code
properties :
taxCode :
$ r e f : "#/components / schemas /
TaxCode "
currently_registered_residence :
type : s t r i n g
Figure 1: Extract of Schema’s semantic network. enum : [ . . . ]
example : ’058103 −(1871 −01 −15) ’
TaxCode :
To achieve this, the Ministry of Culture, MiC, can
type : s t r i n g
provide an e-service, S12, to a cultural institution
d e s c r i p t i o n : h t t p s : / / w3id . o r g /
(e.g., a museum), which, given the unique identifier
i t a l i a / onto /CPV/ taxCode
of a person (tax code) and the municipality where
the cultural asset subject to promotion is located, The addressing to the tax code concept is
retrieves: ensured by the URI identifying the concept
(https://w3id.org/italia/onto/CPV/taxCode), simi- quently data, can fully achieve the objective of “dig-
larly to the use of the controlled vocabulary of cities italization, innovation and security in the Public
(https://w3id.org/italia/controlled-vocabulary/ Administration.” This could be the prompting for
territorial-classifications/cities) for current reg- the digitalization of the entire Italian country.
istered residence. Therefore, unique semantics
emerge as a fundamental tool that, in the reported
use case, enables interoperability among the 3 References
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A. Online Resources
The National Data Catalog (NDC) platform:
• Schema
The sources for data schemas in Schema:
• INAIL
• INPS
The mentioned ontologies in Section 4:
• CLV
• COV
• CPV
• CulturalHeritage
• L0
• Learning
• RPO