an egovernment system for temporal- and semantic-aware access to norms sweg 2006 – the semantic...

An eGovernment system An eGovernment system for temporal- and semantic-aware for temporal- and semantic-aware

access to normsaccess to norms

SWSWEGEG 200 20066 – – The Semantic Web meets eGovernmentThe Semantic Web meets eGovernment

2006 AAAI Spring Symposium Series2006 AAAI Spring Symposium Series, Stanford University, CA, March 2006, Stanford University, CA, March 2006

Fabio GrandiFabio Grandi

Maria Rita ScalasMaria Rita ScalasUniversità degli Studi di BolognaUniversità degli Studi di Bologna

Federica MandreoliFederica Mandreoli

Riccardo MartogliaRiccardo Martoglia

Enrico RonchettiEnrico Ronchetti

Paolo TiberioPaolo TiberioUniversità degli Studi diUniversità degli Studi di

Modena e Reggio EmiliaModena e Reggio Emilia

SWSWEGEG 200 20066 An eGovernment system for temporal- and semantic-aware access to norms An eGovernment system for temporal- and semantic-aware access to norms

OverviewOverview

Our research activities concern the implementation of Our research activities concern the implementation of Web information systems for Web information systems for eGovernmenteGovernment applications applications

Development of eGovernment initiatives: Development of eGovernment initiatives: more and more on-line more and more on-line resourcesresources and and servicesservices are are being made available by Public Administrations (PAs)being made available by Public Administrations (PAs)

We make use of We make use of temporal databasetemporal database and and semantic Websemantic Web techniques to provide techniques to provide personalized accesspersonalized access to such to such resources and servicesresources and services

In particular, we consider In particular, we consider multi-version norm textsmulti-version norm texts (stored in XML format) available in Web repositories(stored in XML format) available in Web repositories


timetime

Original Original normative textnormative text 11 22

new new versionversion

33

new new versionversion

Importance of versioningImportance of versioning Temporal concernsTemporal concerns are ubiquitous in the law domain are ubiquitous in the law domain

Each normative text changes in time due to different Each normative text changes in time due to different modificationsmodifications, , but keeps its but keeps its identityidentity

The ability to model The ability to model temporal dimensiontemporal dimensionss is essential for the is essential for the management of evolving normsmanagement of evolving norms

it is crucial to reconstruct the it is crucial to reconstruct the consolidated versionconsolidated version of a norm of a norm also also past versionspast versions are still important are still important


Importance of versioningImportance of versioning

Applicability (semantic) versioningApplicability (semantic) versioning also plays an important role also plays an important role some norms or some of their parts have or acquire a some norms or some of their parts have or acquire a limited limited

applicabilityapplicability personalized versionpersonalized version of the normof the norm

A version only containing articles which are applicable to a A version only containing articles which are applicable to a citizen’s personal casecitizen’s personal case

Self-employedSelf-employed

Art. 1 (unemployed)Art. 1 (unemployed)

xxy yyx yxyx yyyxx xyyxxxy yyx yxyx yyyxx xyyx

Art. 2 (self-employed)Art. 2 (self-employed)

aab bbab abab abba abaab bbab abab abba ab

Art. 3 (retired)Art. 3 (retired)

qwqq ww wqqw wq wwqwqq ww wqqw wq ww


MotivationMotivation

Large XML collections of norms Large XML collections of norms are made available by the PA on the Web are made available by the PA on the Web but but personalizationpersonalization is:is:

AbsentAbsent, e.g. , e.g. http://www.normeinrete.ithttp://www.normeinrete.it(temporal versioning partially supported)(temporal versioning partially supported)

PredefinedPredefined in the Website structure and contents, in the Website structure and contents, e.g. e.g. http://www.italia.gov.ithttp://www.italia.gov.it(hardwired by human experts following the life-events approach)(hardwired by human experts following the life-events approach)

Lack of an effective, flexible, on-demand Lack of an effective, flexible, on-demand (“intelligent”, efficient) personalization facility(“intelligent”, efficient) personalization facility


ObjectivesObjectives

Development of an Development of an effectiveeffective and and efficientefficient Web information systemWeb information system where where:: norms are represented as norms are represented as XML documentsXML documents dynamics of norms in timedynamics of norms in time is captured is captured limited applicabilitylimited applicability of normsof norms (and their parts) (and their parts)

is capturedis captured selective accessselective access and and reconstruction of versionsreconstruction of versions

is supported by a query engineis supported by a query engine

Aimed at:Aimed at: enabling citizens to access enabling citizens to access personalizedpersonalized versions of versions of

multiversionmultiversion resources resources improving and optimizing the improving and optimizing the involvementinvolvement of citizens of citizens

in the eGovernance processin the eGovernance process


Personalized access to multi-version normsPersonalized access to multi-version norms

Classification of the citizenClassification of the citizenwrt anwrt an ontologyontology

on the basis of his/her on the basis of his/her digital identitydigital identity

Retrieval and reconstructionRetrieval and reconstructionof a of a personalized versionpersonalized version

of the norm to be deliveredof the norm to be delivered

Citizen logged on Citizen logged on to the Web repositoryto the Web repository

looking for a normlooking for a normof interestof interest


The Technological InfrastructureThe Technological Infrastructure

WEB SERVICESWEB SERVICESOF PUBLICOF PUBLIC

ADMINISTRATIONADMINISTRATION

WEB SERVICESWEB SERVICESWITH ONTOLOGYWITH ONTOLOGY

OOCC

XML REPOSITORY OF XML REPOSITORY OF ANNOTATED NORMSANNOTATED NORMS

SIMPLESIMPLEELABORATIONELABORATION

UNITUNIT

1 – 1 – identification phaseidentification phase: reconstruction : reconstruction on-the-flyon-the-fly of the digital of the digital identity of the authenticated useridentity of the authenticated user

11

classclass CCxx

2 – 2 – classification phaseclassification phase: use of the collected digital identity to : use of the collected digital identity to classify the citizen with respect to the classify the citizen with respect to the civic ontology Ocivic ontology Occ

22

Public Public Administration Administration DBDB

creation creation /update/update

3 – 3 – querying phasequerying phase: access and reconstruction of all and only : access and reconstruction of all and only norms which are applicable to the norms which are applicable to the class Cclass Cxx

33 Querying phaseQuerying phase


Definition of a Definition of a temporal XML modeltemporal XML model including including a temporal multi-version XML schemaa temporal multi-version XML schema

is based on the is based on the hierarchical organizationhierarchical organization of normative texts: of normative texts: contents-section-article-paragraphcontents-section-article-paragraph

at each level of the hierarchy, the history of changes is at each level of the hierarchy, the history of changes is represented by the (time-stamped) represented by the (time-stamped) versionsversions produced produced

it supports it supports ancestor-descendant inheritanceancestor-descendant inheritance temporal manipulation operationstemporal manipulation operations

Extension of the XML model with applicability Extension of the XML model with applicability annotations in order to support annotations in order to support semantic versioningsemantic versioning

DesignDesign,, implementation implementation and evaluation and evaluation of of system system prototypesprototypes supporting the model supporting the model

ApproachApproach


The temporal XML The temporal XML schemaschema

4 Temporal Dimensions:4 Temporal Dimensions:

Publication timePublication time

time of publication time of publication on the Official Journalon the Official Journal

Validity timeValidity time

time the norm is in forcetime the norm is in force

Efficacy timeEfficacy time

time the norm time the norm can be appliedcan be applied

Transaction timeTransaction time

time the norm is storedtime the norm is storedin the systemin the system

Law

Title Contents

Publication – R Vt_Start – RVt_End – OTt_Start – RTt_End – OEt_Start – REt_End – O

An_ref – O Ver

Section

Ver

Article

Ver

Heading

Paragraph

Ver

Heading

Num – R

Num – R

Num – R

Num – R

Num – R

An_ref – O

Num – R

An_ref – O

Num – R

An_ref – O

Num – R

Type – R

Vt_Start – RVt_End – OTt_Start – RTt_End – OEt_Start – REt_End – O

TA


TA


TA


TA


Semantic versioningSemantic versioning

Extension of the multi-version model based on temporal Extension of the multi-version model based on temporal dimensions to include a dimensions to include a semantic versioningsemantic versioning dimension to dimension to provide provide personalized accesspersonalized access to norm texts to norm texts

Civic ontologyCivic ontology: a classification of citizens based on the distinctions : a classification of citizens based on the distinctions introduced by successive norms (founding acts) that imply some introduced by successive norms (founding acts) that imply some limitations in their applicabilitylimitations in their applicability

Citizen

EmployeeUnemployed Retired

Self-employedSubordinate

PrivatePublic


Semantic versioningSemantic versioning

At this stage of the project, we manage “tree-like” ontologies class taxonomies induced by the IS-A relationship we exploit the pre-order and post-order properties of trees

New versioning dimension: applicability of different parts of a norm text to the relevant classes of the civic ontology

Applicability annotations (AA) are added to semantic versions

Citizen



PrivatePublic

Citizen



PrivatePublic

(2,1) (3,6) (8,7)

(4,4) (7,5)

(5,2) (6,3)

(1,8)


Semantic versioningSemantic versioning Applicability is inherited by descendant nodes unless locally redefined By means of redefinitions we can also introduce, for each part of a

document, complex applicability properties Restrictions with respect to ancestors Extensions with respect to ancestors

<article num="1"><ver num="1">

<aa applies_to="3"/>[… Temporal attributes … ]<paragraph num="1">

<ver num="1"> [ … Text … ]<aa applies_to="4"/>[… Temporal attributes … ]

</ver></paragraph><paragraph num="2">

<ver num="1"> [ … Text … ]<aa applies_also="8"/>[… Temporal attributes … ]

</ver></paragraph>

</ver></article>

Citizen



PrivatePublic

(2,1) (3,6) (8,7)

(4,4) (7,5)

(5,2) (6,3)

(1,8)


John Smith is a self-employed citizen.John Smith is a self-employed citizen.

He is interested in the text of all the norms ...He is interested in the text of all the norms ...

... which contain paragraphs dealing with health care, ...... which contain paragraphs dealing with health care, ...

... which were valid and in effect between 2002 and 2004, ...... which were valid and in effect between 2002 and 2004, ...

... and which are applicable to his ... and which are applicable to his case (civic class 7).case (civic class 7).

Example of Example of full searchfull search

Structural constraintStructural constraint

Textual constraintTextual constraint

Temporal constraintTemporal constraint

Applicability constraintApplicability constraint

4 orthogonal constraints4 orthogonal constraints


FOR $a IN normsFOR $a IN norms

WHERE textConstr ($a//paragraph//text(), ’health AND care’)WHERE textConstr ($a//paragraph//text(), ’health AND care’)

AND tempConstr (’vTime OVERLAPS PERIOD(’2002-01-01’,’2004-12-31’)’)AND tempConstr (’vTime OVERLAPS PERIOD(’2002-01-01’,’2004-12-31’)’)

AND tempConstr (’eTime OVERLAPS PERIOD(’2002-01-01’,’2004-12-31’)’)AND tempConstr (’eTime OVERLAPS PERIOD(’2002-01-01’,’2004-12-31’)’)

AND applConstr (’class 7’)AND applConstr (’class 7’)

RETURN $aRETURN $a


Structural constraintStructural constraint

Textual constraintTextual constraint

Temporal constraintTemporal constraint

Applicability constraintApplicability constraint

4 orthogonal constraints4 orthogonal constraints


Norm

Article 1

Par 1

Ver 1AA=3

Ver 1

Par 2

Article 2

Health care…Health care………text Xtext X

Ver 2

Public health…Public health………text Ytext Y


TA

AA

TAAA=4

TAVer 1

AA=3,8

TA

Health care…Health care………text Ztext Z

Citizen



PrivatePublic

(2,1) (3,6) (8,7)

(4,4) (7,5)

(5,2) (6,3)

(1,8)

Civic ontologyCivic ontology Normative DBNormative DB

……norm//paragraph//text()norm//paragraph//text()

……‘‘class 7’class 7’

……


Our prototype system (“native” approach)Our prototype system (“native” approach)

The query engine is able to access and retrieve only the strictly necessary data

selection relies on ad-hoc data structures supporting multi-versioning storage granularity is finer than the entire documents used by standard XML engines

Only the parts which satisfy the temporal and applicability constraints are used for the reconstruction of the retrieved documents

There is no need to retrieve whole XML documents and build space-consuming structures such as DOM trees

Enhanced query processing efficiency

Reduced memory requirements


Evaluation benchmarkEvaluation benchmark

Three XML document setsThree XML document sets 5000 documents 5000 documents (120MB) (120MB) 10000 documents 10000 documents (240MB) (240MB) 20000 documents 20000 documents (480MB) (480MB)

Variable document sizeVariable document size min = 2KBmin = 2KB avg = 24KBavg = 24KB max = 125KBmax = 125KB

Five different query typesFive different query types Queries on keywords (structural + textual constraints)Queries on keywords (structural + textual constraints)

Q1Q1 – keywords in contents – keywords in contents Q2Q2 – keywords in type and contents – keywords in type and contents

Temporal queries (structural + temporal constraints)Temporal queries (structural + temporal constraints) Q3Q3 – conditions on publication, validity and transaction time – conditions on publication, validity and transaction time

Mixed queries (structural + textual + temporal constraints)Mixed queries (structural + textual + temporal constraints) Q4Q4,, Q5 Q5 – with keywords and temporal conditions – with keywords and temporal conditions

Five variants with semantic constraintsFive variants with semantic constraints Qx-AQx-A – with additional – with additional applicability constraintsapplicability constraints

PERSONALIZATION PERSONALIZATION OF THE QUERIESOF THE QUERIES


Performance evaluationPerformance evaluation

Very high Very high personalizationpersonalization query query efficiencyefficiency The system is able to solve personalization problems by means The system is able to solve personalization problems by means

of simple comparisons involving pre-post encodingsof simple comparisons involving pre-post encodings 0.5-1%0.5-1% more more timetime than for the original versions than for the original versions 3-4%3-4% storagestorage space overhead space overhead


Performance evaluationPerformance evaluation

Scalability testsScalability tests The computing time grows The computing time grows sublinearlysublinearly with the number of with the number of

documentsdocuments Good scalabilityGood scalability of the system in every type of query context of the system in every type of query context

5000 5000 docsdocs

10000 10000 docsdocs

20000 20000 docsdocs

timetime

1046 1046 msecmsec

1366 1366 msecmsec

1741 1741 msecmsec


ConclusionsConclusions

We presented our research work concerning the design and implementation of efficient Web-based information systems for eGovernment applications

We introduced a personalized access to resources on the basis of the digital identity of citizens relying on semantic versioning and ontology mapping

We developed a efficient platform (“native” approach) for which a specialized Multi-version XML Query Processor has been designed and implemented

We proved our approach to be very efficient in a large set of experimental situations and showed excellent scale-up figures with varying load configurations


Future WorkFuture Work

Extensions of the current framework more advanced application requirements may include a more

sophisticated ontology definition, possibly versioned, and more advanced reasoning services

Development of a complete technological infrastructure usable in a large Web-based eGovernment scenario, including

identification, classification and reconstruction services

Assessment of our prototype systems in a concrete working environment

with real users and with a large repository of real norms

Extension to a more general application domain(Web personalization via ontology-based user profiling)

an egovernment system for temporal- and semantic-aware access to norms sweg 2006 – the semantic...

Documents

norms sweg

semanticaware access

egovernment system

temporal versioning

semantic web meets egovernment

personalized access

temporal dimensions

limited applicability