HISPANA | Directorio nacional de recursos digitales > Record data

Está en:  › Record data

Linked Open Data

∃-STRIPS: existential quantification in planning and constraint satisfaction

Identificadores del recurso

Francès G, Geffner H. ∃-STRIPS: existential quantification in planning and constraint satisfaction. In: Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.

http://hdl.handle.net/10230/34084

Origin

(e-Repositori: Repositori digital de la UPF)

File

Title:: ∃-STRIPS: existential quantification in planning and constraint satisfaction
Tema:: Intel·ligència artificial
Description:: Comunicació presentada a la Twenty-Fifth International Joint Conference on Artificial Intelligence, celebrada els dies 9 a 15 de juliol de 2016 a Nova York.; Existentially quantified variables in goals and action preconditions are part of the standard PDDL planning language, yet few planners support them, while those that do compile them away at an exponential cost. In this work, we argue that existential variables are an essential feature for representing and reasoning with constraints in planning, and that it is harmful to compile them away or avoid them altogether, since this hides part of the problem structure that can be exploited computationally. We show how to do this by formulating an extension of the standard delete-relaxation heuristics that handles existential variables. While this extension is simple, the consequences for both modeling and computation are important. Furthermore, by allowing existential variables in STRIPS and treating them properly, CSPs can be represented and solved in a direct manner as action-less,fluent-less STRIPS planning problems, something important for problems involving restrictions. In addition, functional fluents in Functional STRIPS can be compiled away with no effect on the structure and informativeness of the resulting heuristic. Experiments are reported comparing our native ∃-STRIPS planner with state-of-the-art STRIPS planners over compiled and propositional encodings, and with a Functional STRIPS planner.; This work is partially supported by the M. de Maeztu Programme (MDM-2015-0502) and by grants TIN2015-67959 and CSD2010-00034, MEC, Spain.
Idioma:: English
Relation:: Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.; info:eu-repo/grantAgreement/ES/1PE/TIN2015-67959; info:eu-repo/grantAgreement/ES/3PN/CSD2010-00034
Autor/Productor:: Francès, Guillem; Geffner, Héctor
Publisher:: IJCAI & AAAI Press
Rights:: Copyright © 2016 International Joint Conferences on Artificial Intelligence; info:eu-repo/semantics/openAccess
Date:: 2016
Tipo de recurso:: info:eu-repo/semantics/conferenceObject; info:eu-repo/semantics/publishedVersion
Format:: application/pdf

oai_dc

<?xml version="1.0" encoding="UTF-8" ?>

<oai_dc:dc schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
1. <dc:title>∃-STRIPS: existential quantification in planning and constraint satisfaction</dc:title>
2. <dc:creator>Francès, Guillem</dc:creator>
3. <dc:creator>Geffner, Héctor</dc:creator>
4. <dc:subject>Intel·ligència artificial</dc:subject>
5. <dc:description>Comunicació presentada a la Twenty-Fifth International Joint Conference on Artificial Intelligence, celebrada els dies 9 a 15 de juliol de 2016 a Nova York.</dc:description>
6. <dc:description>Existentially quantified variables in goals and action preconditions are part of the standard PDDL planning language, yet few planners support them, while those that do compile them away at an exponential cost. In this work, we argue that existential variables are an essential feature for representing and reasoning with constraints in planning, and that it is harmful to compile them away or avoid them altogether, since this hides part of the problem structure that can be exploited computationally. We show how to do this by formulating an extension of the standard delete-relaxation heuristics that handles existential variables. While this extension is simple, the consequences for both modeling and computation are important. Furthermore, by allowing existential variables in STRIPS and treating them properly, CSPs can be represented and solved in a direct manner as action-less,fluent-less STRIPS planning problems, something important for problems involving restrictions. In addition, functional fluents in Functional STRIPS can be compiled away with no effect on the structure and informativeness of the resulting heuristic. Experiments are reported comparing our native ∃-STRIPS planner with state-of-the-art STRIPS planners over compiled and propositional encodings, and with a Functional STRIPS planner.</dc:description>
7. <dc:description>This work is partially supported by the M. de Maeztu Programme (MDM-2015-0502) and by grants TIN2015-67959 and CSD2010-00034, MEC, Spain.</dc:description>
8. <dc:date>2016</dc:date>
9. <dc:type>info:eu-repo/semantics/conferenceObject</dc:type>
10. <dc:type>info:eu-repo/semantics/publishedVersion</dc:type>
11. <dc:identifier>Francès G, Geffner H. ∃-STRIPS: existential quantification in planning and constraint satisfaction. In: Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</dc:identifier>
12. <dc:identifier>http://hdl.handle.net/10230/34084</dc:identifier>
13. <dc:language>eng</dc:language>
14. <dc:relation>Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</dc:relation>
15. <dc:relation>info:eu-repo/grantAgreement/ES/1PE/TIN2015-67959</dc:relation>
16. <dc:relation>info:eu-repo/grantAgreement/ES/3PN/CSD2010-00034</dc:relation>
17. <dc:rights>Copyright © 2016 International Joint Conferences on Artificial Intelligence</dc:rights>
18. <dc:rights>info:eu-repo/semantics/openAccess</dc:rights>
19. <dc:format>application/pdf</dc:format>
20. <dc:publisher>IJCAI & AAAI Press</dc:publisher>
</oai_dc:dc>

didl

<?xml version="1.0" encoding="UTF-8" ?>

<d:DIDL schemaLocation="urn:mpeg:mpeg21:2002:02-DIDL-NS http://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-21_schema_files/did/didl.xsd">
1. <d:DIDLInfo>
  1. <dcterms:created schemaLocation="http://purl.org/dc/terms/ http://dublincore.org/schemas/xmls/qdc/dcterms.xsd">2018-03-12T10:49:54Z</dcterms:created>
  </d:DIDLInfo>
2. <d:Item id="hdl_10230_34084">
  1. <d:Descriptor>
    1. <d:Statement mimeType="application/xml; charset=utf-8">
      1. <dii:Identifier schemaLocation="urn:mpeg:mpeg21:2002:01-DII-NS http://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-21_schema_files/dii/dii.xsd">urn:hdl:10230/34084</dii:Identifier>
      </d:Statement>
    </d:Descriptor>
  2. <d:Descriptor>
    1. <d:Statement mimeType="application/xml; charset=utf-8">
      1. <oai_dc:dc schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
        <dc:title>∃-STRIPS: existential quantification in planning and constraint satisfaction</dc:title>
        <dc:creator>Francès, Guillem</dc:creator>
        <dc:creator>Geffner, Héctor</dc:creator>
        <dc:description>Comunicació presentada a la Twenty-Fifth International Joint Conference on Artificial Intelligence, celebrada els dies 9 a 15 de juliol de 2016 a Nova York.</dc:description>
        <dc:description>Existentially quantified variables in goals and action preconditions are part of the standard PDDL planning language, yet few planners support them, while those that do compile them away at an exponential cost. In this work, we argue that existential variables are an essential feature for representing and reasoning with constraints in planning, and that it is harmful to compile them away or avoid them altogether, since this hides part of the problem structure that can be exploited computationally. We show how to do this by formulating an extension of the standard delete-relaxation heuristics that handles existential variables. While this extension is simple, the consequences for both modeling and computation are important. Furthermore, by allowing existential variables in STRIPS and treating them properly, CSPs can be represented and solved in a direct manner as action-less,fluent-less STRIPS planning problems, something important for problems involving restrictions. In addition, functional fluents in Functional STRIPS can be compiled away with no effect on the structure and informativeness of the resulting heuristic. Experiments are reported comparing our native ∃-STRIPS planner with state-of-the-art STRIPS planners over compiled and propositional encodings, and with a Functional STRIPS planner.</dc:description>
        <dc:date>2018-03-12T10:49:54Z</dc:date>
        <dc:date>2018-03-12T10:49:54Z</dc:date>
        <dc:date>2016</dc:date>
        <dc:type>info:eu-repo/semantics/conferenceObject</dc:type>
        <dc:identifier>Francès G, Geffner H. ∃-STRIPS: existential quantification in planning and constraint satisfaction. In: Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</dc:identifier>
        <dc:identifier>http://hdl.handle.net/10230/34084</dc:identifier>
        <dc:language>eng</dc:language>
        <dc:relation>Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</dc:relation>
        <dc:relation>info:eu-repo/grantAgreement/ES/1PE/TIN2015-67959</dc:relation>
        <dc:relation>info:eu-repo/grantAgreement/ES/3PN/CSD2010-00034</dc:relation>
        <dc:rights>info:eu-repo/semantics/openAccess</dc:rights>
        <dc:rights>Copyright © 2016 International Joint Conferences on Artificial Intelligence</dc:rights>
        <dc:publisher>IJCAI & AAAI Press</dc:publisher>
        </oai_dc:dc>
      </d:Statement>
    </d:Descriptor>
  3. <d:Component id="10230_34084_1">
    1. <d:Resource mimeType="application/pdf" ref="http://repositori.upf.edu/bitstream/10230/34084/1/Frances_IJCAI2016_stri.pdf" />
    </d:Component>
  </d:Item>
</d:DIDL>

dim

<?xml version="1.0" encoding="UTF-8" ?>

<dim:dim schemaLocation="http://www.dspace.org/xmlns/dspace/dim http://www.dspace.org/schema/dim.xsd">
1. <dim:field element="contributor" lang="ca" mdschema="dc" qualifier="author">Francès, Guillem</dim:field>
2. <dim:field element="contributor" lang="ca" mdschema="dc" qualifier="author">Geffner, Héctor</dim:field>
3. <dim:field element="date" mdschema="dc" qualifier="accessioned">2018-03-12T10:49:54Z</dim:field>
4. <dim:field element="date" mdschema="dc" qualifier="available">2018-03-12T10:49:54Z</dim:field>
5. <dim:field element="date" mdschema="dc" qualifier="issued">2016</dim:field>
6. <dim:field element="identifier" mdschema="dc" qualifier="citation">Francès G, Geffner H. ∃-STRIPS: existential quantification in planning and constraint satisfaction. In: Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</dim:field>
7. <dim:field element="identifier" mdschema="dc" qualifier="uri">http://hdl.handle.net/10230/34084</dim:field>
8. <dim:field element="description" mdschema="dc">Comunicació presentada a la Twenty-Fifth International Joint Conference on Artificial Intelligence, celebrada els dies 9 a 15 de juliol de 2016 a Nova York.</dim:field>
9. <dim:field element="description" lang="en" mdschema="dc" qualifier="abstract">Existentially quantified variables in goals and action preconditions are part of the standard PDDL planning language, yet few planners support them, while those that do compile them away at an exponential cost. In this work, we argue that existential variables are an essential feature for representing and reasoning with constraints in planning, and that it is harmful to compile them away or avoid them altogether, since this hides part of the problem structure that can be exploited computationally. We show how to do this by formulating an extension of the standard delete-relaxation heuristics that handles existential variables. While this extension is simple, the consequences for both modeling and computation are important. Furthermore, by allowing existential variables in STRIPS and treating them properly, CSPs can be represented and solved in a direct manner as action-less,fluent-less STRIPS planning problems, something important for problems involving restrictions. In addition, functional fluents in Functional STRIPS can be compiled away with no effect on the structure and informativeness of the resulting heuristic. Experiments are reported comparing our native ∃-STRIPS planner with state-of-the-art STRIPS planners over compiled and propositional encodings, and with a Functional STRIPS planner.</dim:field>
10. <dim:field element="description" lang="en" mdschema="dc" qualifier="provenance">Made available in DSpace on 2018-03-12T10:49:54Z (GMT). No. of bitstreams: 1 Frances_IJCAI2016_stri.pdf: 576057 bytes, checksum: f1d269d70142e6eaa4c3464ae461bfda (MD5) Previous issue date: 2016</dim:field>
11. <dim:field element="description" mdschema="dc" qualifier="sponsorship">This work is partially supported by the M. de Maeztu Programme (MDM-2015-0502) and by grants TIN2015-67959 and CSD2010-00034, MEC, Spain.</dim:field>
12. <dim:field element="format" mdschema="dc" qualifier="mimetype">application/pdf</dim:field>
13. <dim:field element="language" mdschema="dc" qualifier="iso">eng</dim:field>
14. <dim:field element="publisher" lang="ca" mdschema="dc">IJCAI & AAAI Press</dim:field>
15. <dim:field element="relation" mdschema="dc" qualifier="ispartof">Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</dim:field>
16. <dim:field element="relation" mdschema="dc" qualifier="projectID">info:eu-repo/grantAgreement/ES/1PE/TIN2015-67959</dim:field>
17. <dim:field element="relation" mdschema="dc" qualifier="projectID">info:eu-repo/grantAgreement/ES/3PN/CSD2010-00034</dim:field>
18. <dim:field element="rights" mdschema="dc">Copyright © 2016 International Joint Conferences on Artificial Intelligence</dim:field>
19. <dim:field element="rights" mdschema="dc" qualifier="accessRights">info:eu-repo/semantics/openAccess</dim:field>
20. <dim:field element="subject" mdschema="dc" qualifier="other">Intel·ligència artificial</dim:field>
21. <dim:field element="title" lang="ca" mdschema="dc">∃-STRIPS: existential quantification in planning and constraint satisfaction</dim:field>
22. <dim:field element="type" mdschema="dc">info:eu-repo/semantics/conferenceObject</dim:field>
23. <dim:field element="type" mdschema="dc" qualifier="version">info:eu-repo/semantics/publishedVersion</dim:field>
</dim:dim>

etdms

<?xml version="1.0" encoding="UTF-8" ?>

<thesis schemaLocation="http://www.ndltd.org/standards/metadata/etdms/1.0/ http://www.ndltd.org/standards/metadata/etdms/1.0/etdms.xsd">
1. <title>∃-STRIPS: existential quantification in planning and constraint satisfaction</title>
2. <creator>Francès, Guillem</creator>
3. <creator>Geffner, Héctor</creator>
4. <description>Comunicació presentada a la Twenty-Fifth International Joint Conference on Artificial Intelligence, celebrada els dies 9 a 15 de juliol de 2016 a Nova York.</description>
5. <description>Existentially quantified variables in goals and action preconditions are part of the standard PDDL planning language, yet few planners support them, while those that do compile them away at an exponential cost. In this work, we argue that existential variables are an essential feature for representing and reasoning with constraints in planning, and that it is harmful to compile them away or avoid them altogether, since this hides part of the problem structure that can be exploited computationally. We show how to do this by formulating an extension of the standard delete-relaxation heuristics that handles existential variables. While this extension is simple, the consequences for both modeling and computation are important. Furthermore, by allowing existential variables in STRIPS and treating them properly, CSPs can be represented and solved in a direct manner as action-less,fluent-less STRIPS planning problems, something important for problems involving restrictions. In addition, functional fluents in Functional STRIPS can be compiled away with no effect on the structure and informativeness of the resulting heuristic. Experiments are reported comparing our native ∃-STRIPS planner with state-of-the-art STRIPS planners over compiled and propositional encodings, and with a Functional STRIPS planner.</description>
6. <date>2018-03-12</date>
7. <date>2018-03-12</date>
8. <date>2016</date>
9. <type>info:eu-repo/semantics/conferenceObject</type>
10. <identifier>Francès G, Geffner H. ∃-STRIPS: existential quantification in planning and constraint satisfaction. In: Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</identifier>
11. <identifier>http://hdl.handle.net/10230/34084</identifier>
12. <language>eng</language>
13. <relation>Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</relation>
14. <relation>info:eu-repo/grantAgreement/ES/1PE/TIN2015-67959</relation>
15. <relation>info:eu-repo/grantAgreement/ES/3PN/CSD2010-00034</relation>
16. <rights>info:eu-repo/semantics/openAccess</rights>
17. <rights>Copyright © 2016 International Joint Conferences on Artificial Intelligence</rights>
18. <publisher>IJCAI & AAAI Press</publisher>
</thesis>

marc

<?xml version="1.0" encoding="UTF-8" ?>

<record schemaLocation="http://www.loc.gov/MARC21/slim http://www.loc.gov/standards/marcxml/schema/MARC21slim.xsd">
1. <leader>00925njm 22002777a 4500</leader>
2. <datafield ind1=" " ind2=" " tag="042">
  1. <subfield code="a">dc</subfield>
  </datafield>
3. <datafield ind1=" " ind2=" " tag="720">
  1. <subfield code="a">Francès, Guillem</subfield>
  2. <subfield code="e">author</subfield>
  </datafield>
4. <datafield ind1=" " ind2=" " tag="720">
  1. <subfield code="a">Geffner, Héctor</subfield>
  2. <subfield code="e">author</subfield>
  </datafield>
5. <datafield ind1=" " ind2=" " tag="260">
  1. <subfield code="c">2016</subfield>
  </datafield>
6. <datafield ind1=" " ind2=" " tag="520">
  1. <subfield code="a">Existentially quantified variables in goals and action preconditions are part of the standard PDDL planning language, yet few planners support them, while those that do compile them away at an exponential cost. In this work, we argue that existential variables are an essential feature for representing and reasoning with constraints in planning, and that it is harmful to compile them away or avoid them altogether, since this hides part of the problem structure that can be exploited computationally. We show how to do this by formulating an extension of the standard delete-relaxation heuristics that handles existential variables. While this extension is simple, the consequences for both modeling and computation are important. Furthermore, by allowing existential variables in STRIPS and treating them properly, CSPs can be represented and solved in a direct manner as action-less,fluent-less STRIPS planning problems, something important for problems involving restrictions. In addition, functional fluents in Functional STRIPS can be compiled away with no effect on the structure and informativeness of the resulting heuristic. Experiments are reported comparing our native ∃-STRIPS planner with state-of-the-art STRIPS planners over compiled and propositional encodings, and with a Functional STRIPS planner.</subfield>
  </datafield>
7. <datafield ind1="8" ind2=" " tag="024">
  1. <subfield code="a">Francès G, Geffner H. ∃-STRIPS: existential quantification in planning and constraint satisfaction. In: Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</subfield>
  </datafield>
8. <datafield ind1="8" ind2=" " tag="024">
  1. <subfield code="a">http://hdl.handle.net/10230/34084</subfield>
  </datafield>
9. <datafield ind1="0" ind2="0" tag="245">
  1. <subfield code="a">∃-STRIPS: existential quantification in planning and constraint satisfaction</subfield>
  </datafield>
</record>

mets

<?xml version="1.0" encoding="UTF-8" ?>

<mets ID=" DSpace_ITEM_10230-34084" OBJID=" hdl:10230/34084" PROFILE="DSpace METS SIP Profile 1.0" TYPE="DSpace ITEM" schemaLocation="http://www.loc.gov/METS/ http://www.loc.gov/standards/mets/mets.xsd">
1. <metsHdr CREATEDATE="2022-11-15T19:44:55Z">
  1. <agent ROLE="CUSTODIAN" TYPE="ORGANIZATION">
    1. <name>Repositori digital de la UPF</name>
    </agent>
  </metsHdr>
2. <dmdSec ID="DMD_10230_34084">
  1. <mdWrap MDTYPE="MODS">
    1. <xmlData schemaLocation="http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-1.xsd">
      1. <mods:mods schemaLocation="http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-1.xsd">
        <mods:name>
        <mods:role>
        <mods:roleTerm type="text">author</mods:roleTerm>
        </mods:role>
        <mods:namePart>Francès, Guillem</mods:namePart>
        </mods:name>
        <mods:name>
        <mods:role>
        <mods:roleTerm type="text">author</mods:roleTerm>
        </mods:role>
        <mods:namePart>Geffner, Héctor</mods:namePart>
        </mods:name>
        <mods:extension>
        <mods:dateAccessioned encoding="iso8601">2018-03-12T10:49:54Z</mods:dateAccessioned>
        </mods:extension>
        <mods:extension>
        <mods:dateAvailable encoding="iso8601">2018-03-12T10:49:54Z</mods:dateAvailable>
        </mods:extension>
        <mods:originInfo>
        <mods:dateIssued encoding="iso8601">2016</mods:dateIssued>
        </mods:originInfo>
        <mods:identifier type="citation">Francès G, Geffner H. ∃-STRIPS: existential quantification in planning and constraint satisfaction. In: Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</mods:identifier>
        <mods:identifier type="uri">http://hdl.handle.net/10230/34084</mods:identifier>
        <mods:abstract>Existentially quantified variables in goals and action preconditions are part of the standard PDDL planning language, yet few planners support them, while those that do compile them away at an exponential cost. In this work, we argue that existential variables are an essential feature for representing and reasoning with constraints in planning, and that it is harmful to compile them away or avoid them altogether, since this hides part of the problem structure that can be exploited computationally. We show how to do this by formulating an extension of the standard delete-relaxation heuristics that handles existential variables. While this extension is simple, the consequences for both modeling and computation are important. Furthermore, by allowing existential variables in STRIPS and treating them properly, CSPs can be represented and solved in a direct manner as action-less,fluent-less STRIPS planning problems, something important for problems involving restrictions. In addition, functional fluents in Functional STRIPS can be compiled away with no effect on the structure and informativeness of the resulting heuristic. Experiments are reported comparing our native ∃-STRIPS planner with state-of-the-art STRIPS planners over compiled and propositional encodings, and with a Functional STRIPS planner.</mods:abstract>
        <mods:language>
        <mods:languageTerm authority="rfc3066">eng</mods:languageTerm>
        </mods:language>
        <mods:accessCondition type="useAndReproduction">Copyright © 2016 International Joint Conferences on Artificial Intelligence</mods:accessCondition>
        <mods:titleInfo>
        <mods:title>∃-STRIPS: existential quantification in planning and constraint satisfaction</mods:title>
        </mods:titleInfo>
        <mods:genre>info:eu-repo/semantics/conferenceObject</mods:genre>
        </mods:mods>
      </xmlData>
    </mdWrap>
  </dmdSec>
3. <amdSec ID="FO_10230_34084_1">
  1. <techMD ID="TECH_O_10230_34084_1">
    1. <mdWrap MDTYPE="PREMIS">
      1. <xmlData schemaLocation="http://www.loc.gov/standards/premis http://www.loc.gov/standards/premis/PREMIS-v1-0.xsd">
        <premis:premis>
        <premis:object>
        <premis:objectIdentifier>
        <premis:objectIdentifierType>URL</premis:objectIdentifierType>
        <premis:objectIdentifierValue>http://repositori.upf.edu/bitstream/10230/34084/1/Frances_IJCAI2016_stri.pdf</premis:objectIdentifierValue>
        </premis:objectIdentifier>
        <premis:objectCategory>File</premis:objectCategory>
        <premis:objectCharacteristics>
        <premis:fixity>
        <premis:messageDigestAlgorithm>MD5</premis:messageDigestAlgorithm>
        <premis:messageDigest>f1d269d70142e6eaa4c3464ae461bfda</premis:messageDigest>
        </premis:fixity>
        <premis:size>576057</premis:size>
        <premis:format>
        <premis:formatDesignation>
        <premis:formatName>application/pdf</premis:formatName>
        </premis:formatDesignation>
        </premis:format>
        </premis:objectCharacteristics>
        <premis:originalName>Frances_IJCAI2016_stri.pdf</premis:originalName>
        </premis:object>
        </premis:premis>
        </xmlData>
      </mdWrap>
    </techMD>
  </amdSec>
4. <amdSec ID="FT_10230_34084_2">
  1. <techMD ID="TECH_T_10230_34084_2">
    1. <mdWrap MDTYPE="PREMIS">
      1. <xmlData schemaLocation="http://www.loc.gov/standards/premis http://www.loc.gov/standards/premis/PREMIS-v1-0.xsd">
        <premis:premis>
        <premis:object>
        <premis:objectIdentifier>
        <premis:objectIdentifierType>URL</premis:objectIdentifierType>
        <premis:objectIdentifierValue>http://repositori.upf.edu/bitstream/10230/34084/2/Frances_IJCAI2016_stri.pdf.txt</premis:objectIdentifierValue>
        </premis:objectIdentifier>
        <premis:objectCategory>File</premis:objectCategory>
        <premis:objectCharacteristics>
        <premis:fixity>
        <premis:messageDigestAlgorithm>MD5</premis:messageDigestAlgorithm>
        <premis:messageDigest>90b7fcd31253344ab4496c090879f87e</premis:messageDigest>
        </premis:fixity>
        <premis:size>39154</premis:size>
        <premis:format>
        <premis:formatDesignation>
        <premis:formatName>text/plain</premis:formatName>
        </premis:formatDesignation>
        </premis:format>
        </premis:objectCharacteristics>
        <premis:originalName>Frances_IJCAI2016_stri.pdf.txt</premis:originalName>
        </premis:object>
        </premis:premis>
        </xmlData>
      </mdWrap>
    </techMD>
  </amdSec>
5. <fileSec>
  1. <fileGrp USE="ORIGINAL">
    1. <file ADMID="FO_10230_34084_1" CHECKSUM="f1d269d70142e6eaa4c3464ae461bfda" CHECKSUMTYPE="MD5" GROUPID="GROUP_BITSTREAM_10230_34084_1" ID="BITSTREAM_ORIGINAL_10230_34084_1" MIMETYPE="application/pdf" SEQ="1" SIZE="576057">
      1. <FLocat LOCTYPE="URL" href="http://repositori.upf.edu/bitstream/10230/34084/1/Frances_IJCAI2016_stri.pdf" type="simple" />
      </file>
    </fileGrp>
  2. <fileGrp USE="TEXT">
    1. <file ADMID="FT_10230_34084_2" CHECKSUM="90b7fcd31253344ab4496c090879f87e" CHECKSUMTYPE="MD5" GROUPID="GROUP_BITSTREAM_10230_34084_2" ID="BITSTREAM_TEXT_10230_34084_2" MIMETYPE="text/plain" SEQ="2" SIZE="39154">
      1. <FLocat LOCTYPE="URL" href="http://repositori.upf.edu/bitstream/10230/34084/2/Frances_IJCAI2016_stri.pdf.txt" type="simple" />
      </file>
    </fileGrp>
  </fileSec>
6. <structMap LABEL="DSpace Object" TYPE="LOGICAL">
  1. <div ADMID="DMD_10230_34084" TYPE="DSpace Object Contents">
    1. <div TYPE="DSpace BITSTREAM">
      1. <fptr FILEID="BITSTREAM_ORIGINAL_10230_34084_1" />
      </div>
    </div>
  </structMap>
</mets>

mods

<?xml version="1.0" encoding="UTF-8" ?>

<mods:mods schemaLocation="http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-1.xsd">
1. <mods:name>
  1. <mods:namePart>Francès, Guillem</mods:namePart>
  </mods:name>
2. <mods:name>
  1. <mods:namePart>Geffner, Héctor</mods:namePart>
  </mods:name>
3. <mods:extension>
  1. <mods:dateAvailable encoding="iso8601">2018-03-12T10:49:54Z</mods:dateAvailable>
  </mods:extension>
4. <mods:extension>
  1. <mods:dateAccessioned encoding="iso8601">2018-03-12T10:49:54Z</mods:dateAccessioned>
  </mods:extension>
5. <mods:originInfo>
  1. <mods:dateIssued encoding="iso8601">2016</mods:dateIssued>
  </mods:originInfo>
6. <mods:identifier type="citation">Francès G, Geffner H. ∃-STRIPS: existential quantification in planning and constraint satisfaction. In: Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</mods:identifier>
7. <mods:identifier type="uri">http://hdl.handle.net/10230/34084</mods:identifier>
8. <mods:abstract>Existentially quantified variables in goals and action preconditions are part of the standard PDDL planning language, yet few planners support them, while those that do compile them away at an exponential cost. In this work, we argue that existential variables are an essential feature for representing and reasoning with constraints in planning, and that it is harmful to compile them away or avoid them altogether, since this hides part of the problem structure that can be exploited computationally. We show how to do this by formulating an extension of the standard delete-relaxation heuristics that handles existential variables. While this extension is simple, the consequences for both modeling and computation are important. Furthermore, by allowing existential variables in STRIPS and treating them properly, CSPs can be represented and solved in a direct manner as action-less,fluent-less STRIPS planning problems, something important for problems involving restrictions. In addition, functional fluents in Functional STRIPS can be compiled away with no effect on the structure and informativeness of the resulting heuristic. Experiments are reported comparing our native ∃-STRIPS planner with state-of-the-art STRIPS planners over compiled and propositional encodings, and with a Functional STRIPS planner.</mods:abstract>
9. <mods:language>
  1. <mods:languageTerm>eng</mods:languageTerm>
  </mods:language>
10. <mods:accessCondition type="useAndReproduction">info:eu-repo/semantics/openAccess</mods:accessCondition>
11. <mods:accessCondition type="useAndReproduction">Copyright © 2016 International Joint Conferences on Artificial Intelligence</mods:accessCondition>
12. <mods:titleInfo>
  1. <mods:title>∃-STRIPS: existential quantification in planning and constraint satisfaction</mods:title>
  </mods:titleInfo>
13. <mods:genre>info:eu-repo/semantics/conferenceObject</mods:genre>
</mods:mods>

ore

<?xml version="1.0" encoding="UTF-8" ?>

<atom:entry schemaLocation="http://www.w3.org/2005/Atom http://www.kbcafe.com/rss/atom.xsd.xml">
1. <atom:id>http://oai-repositori.upf.edu/oai/metadata/handle/10230/34084/ore.xml</atom:id>
2. <atom:link href="http://hdl.handle.net/10230/34084" rel="alternate" />
3. <atom:link href="http://oai-repositori.upf.edu/oai/metadata/handle/10230/34084/ore.xml" rel="http://www.openarchives.org/ore/terms/describes" />
4. <atom:link href="http://oai-repositori.upf.edu/oai/metadata/handle/10230/34084/ore.xml#atom" rel="self" type="application/atom+xml" />
5. <atom:published>2018-03-12T10:49:54Z</atom:published>
6. <atom:updated>2018-03-12T10:49:54Z</atom:updated>
7. <atom:source>
  1. <atom:generator>Repositori digital de la UPF</atom:generator>
  </atom:source>
8. <atom:title>∃-STRIPS: existential quantification in planning and constraint satisfaction</atom:title>
9. <atom:author>
  1. <atom:name>Francès, Guillem</atom:name>
  </atom:author>
10. <atom:author>
  1. <atom:name>Geffner, Héctor</atom:name>
  </atom:author>
11. <atom:category label="Aggregation" scheme="http://www.openarchives.org/ore/terms/" term="http://www.openarchives.org/ore/terms/Aggregation" />
12. <atom:category scheme="http://www.openarchives.org/ore/atom/modified" term="2018-03-12T10:49:54Z" />
13. <atom:category label="DSpace Item" scheme="http://www.dspace.org/objectModel/" term="DSpaceItem" />
14. <atom:link href="http://repositori.upf.edu/bitstream/10230/34084/1/Frances_IJCAI2016_stri.pdf" length="576057" rel="http://www.openarchives.org/ore/terms/aggregates" title="Frances_IJCAI2016_stri.pdf" type="application/pdf" />
15. <oreatom:triples>
  1. <rdf:Description about="http://oai-repositori.upf.edu/oai/metadata/handle/10230/34084/ore.xml#atom">
    1. <rdf:type resource="http://www.dspace.org/objectModel/DSpaceItem" />
    2. <dcterms:modified>2018-03-12T10:49:54Z</dcterms:modified>
    </rdf:Description>
  2. <rdf:Description about="http://repositori.upf.edu/bitstream/10230/34084/3/Frances_IJCAI2016_stri.pdf.jpg">
    1. <rdf:type resource="http://www.dspace.org/objectModel/DSpaceBitstream" />
    2. <dcterms:description>THUMBNAIL</dcterms:description>
    </rdf:Description>
  3. <rdf:Description about="http://repositori.upf.edu/bitstream/10230/34084/2/Frances_IJCAI2016_stri.pdf.txt">
    1. <rdf:type resource="http://www.dspace.org/objectModel/DSpaceBitstream" />
    2. <dcterms:description>TEXT</dcterms:description>
    </rdf:Description>
  4. <rdf:Description about="http://repositori.upf.edu/bitstream/10230/34084/1/Frances_IJCAI2016_stri.pdf">
    1. <rdf:type resource="http://www.dspace.org/objectModel/DSpaceBitstream" />
    2. <dcterms:description>ORIGINAL</dcterms:description>
    </rdf:Description>
  </oreatom:triples>
</atom:entry>

qdc

<?xml version="1.0" encoding="UTF-8" ?>

<qdc:qualifieddc schemaLocation="http://purl.org/dc/elements/1.1/ http://dublincore.org/schemas/xmls/qdc/2006/01/06/dc.xsd http://purl.org/dc/terms/ http://dublincore.org/schemas/xmls/qdc/2006/01/06/dcterms.xsd http://dspace.org/qualifieddc/ http://www.ukoln.ac.uk/metadata/dcmi/xmlschema/qualifieddc.xsd">
1. <dc:title>∃-STRIPS: existential quantification in planning and constraint satisfaction</dc:title>
2. <dc:creator>Francès, Guillem</dc:creator>
3. <dc:creator>Geffner, Héctor</dc:creator>
4. <dcterms:abstract>Existentially quantified variables in goals and action preconditions are part of the standard PDDL planning language, yet few planners support them, while those that do compile them away at an exponential cost. In this work, we argue that existential variables are an essential feature for representing and reasoning with constraints in planning, and that it is harmful to compile them away or avoid them altogether, since this hides part of the problem structure that can be exploited computationally. We show how to do this by formulating an extension of the standard delete-relaxation heuristics that handles existential variables. While this extension is simple, the consequences for both modeling and computation are important. Furthermore, by allowing existential variables in STRIPS and treating them properly, CSPs can be represented and solved in a direct manner as action-less,fluent-less STRIPS planning problems, something important for problems involving restrictions. In addition, functional fluents in Functional STRIPS can be compiled away with no effect on the structure and informativeness of the resulting heuristic. Experiments are reported comparing our native ∃-STRIPS planner with state-of-the-art STRIPS planners over compiled and propositional encodings, and with a Functional STRIPS planner.</dcterms:abstract>
5. <dc:date>2016</dc:date>
6. <dc:type>info:eu-repo/semantics/conferenceObject</dc:type>
7. <dc:identifier>Francès G, Geffner H. ∃-STRIPS: existential quantification in planning and constraint satisfaction. In: Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</dc:identifier>
8. <dc:identifier>http://hdl.handle.net/10230/34084</dc:identifier>
9. <dc:language>eng</dc:language>
10. <dc:relation>Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</dc:relation>
11. <dc:relation>info:eu-repo/grantAgreement/ES/1PE/TIN2015-67959</dc:relation>
12. <dc:relation>info:eu-repo/grantAgreement/ES/3PN/CSD2010-00034</dc:relation>
13. <dc:rights>info:eu-repo/semantics/openAccess</dc:rights>
14. <dc:rights>Copyright © 2016 International Joint Conferences on Artificial Intelligence</dc:rights>
15. <dc:publisher>IJCAI & AAAI Press</dc:publisher>
</qdc:qualifieddc>

rdf

<?xml version="1.0" encoding="UTF-8" ?>

<rdf:RDF schemaLocation="http://www.openarchives.org/OAI/2.0/rdf/ http://www.openarchives.org/OAI/2.0/rdf.xsd">
1. <ow:Publication about="oai:repositori.upf.edu:10230/34084">
  1. <dc:title>∃-STRIPS: existential quantification in planning and constraint satisfaction</dc:title>
  2. <dc:creator>Francès, Guillem</dc:creator>
  3. <dc:creator>Geffner, Héctor</dc:creator>
  4. <dc:description>Comunicació presentada a la Twenty-Fifth International Joint Conference on Artificial Intelligence, celebrada els dies 9 a 15 de juliol de 2016 a Nova York.</dc:description>
  5. <dc:description>Existentially quantified variables in goals and action preconditions are part of the standard PDDL planning language, yet few planners support them, while those that do compile them away at an exponential cost. In this work, we argue that existential variables are an essential feature for representing and reasoning with constraints in planning, and that it is harmful to compile them away or avoid them altogether, since this hides part of the problem structure that can be exploited computationally. We show how to do this by formulating an extension of the standard delete-relaxation heuristics that handles existential variables. While this extension is simple, the consequences for both modeling and computation are important. Furthermore, by allowing existential variables in STRIPS and treating them properly, CSPs can be represented and solved in a direct manner as action-less,fluent-less STRIPS planning problems, something important for problems involving restrictions. In addition, functional fluents in Functional STRIPS can be compiled away with no effect on the structure and informativeness of the resulting heuristic. Experiments are reported comparing our native ∃-STRIPS planner with state-of-the-art STRIPS planners over compiled and propositional encodings, and with a Functional STRIPS planner.</dc:description>
  6. <dc:date>2016</dc:date>
  7. <dc:type>info:eu-repo/semantics/conferenceObject</dc:type>
  8. <dc:identifier>Francès G, Geffner H. ∃-STRIPS: existential quantification in planning and constraint satisfaction. In: Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</dc:identifier>
  9. <dc:identifier>http://hdl.handle.net/10230/34084</dc:identifier>
  10. <dc:language>eng</dc:language>
  11. <dc:relation>Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</dc:relation>
  12. <dc:relation>info:eu-repo/grantAgreement/ES/1PE/TIN2015-67959</dc:relation>
  13. <dc:relation>info:eu-repo/grantAgreement/ES/3PN/CSD2010-00034</dc:relation>
  14. <dc:rights>info:eu-repo/semantics/openAccess</dc:rights>
  15. <dc:rights>Copyright © 2016 International Joint Conferences on Artificial Intelligence</dc:rights>
  16. <dc:publisher>IJCAI & AAAI Press</dc:publisher>
  </ow:Publication>
</rdf:RDF>

xoai

<?xml version="1.0" encoding="UTF-8" ?>

<metadata schemaLocation="http://www.lyncode.com/xoai http://www.lyncode.com/xsd/xoai.xsd">
1. <element name="dc">
  1. <element name="contributor">
    1. <element name="author">
      1. <element name="ca">
        <field name="value">Francès, Guillem</field>
        <field name="value">Geffner, Héctor</field>
        </element>
      </element>
    </element>
  2. <element name="date">
    1. <element name="accessioned">
      1. <element name="none">
        <field name="value">2018-03-12T10:49:54Z</field>
        </element>
      </element>
    2. <element name="available">
      1. <element name="none">
        <field name="value">2018-03-12T10:49:54Z</field>
        </element>
      </element>
    3. <element name="issued">
      1. <element name="none">
        <field name="value">2016</field>
        </element>
      </element>
    </element>
  3. <element name="identifier">
    1. <element name="citation">
      1. <element name="none">
        <field name="value">Francès G, Geffner H. ∃-STRIPS: existential quantification in planning and constraint satisfaction. In: Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</field>
        </element>
      </element>
    2. <element name="uri">
      1. <element name="none">
        <field name="value">http://hdl.handle.net/10230/34084</field>
        </element>
      </element>
    </element>
  4. <element name="description">
    1. <element name="none">
      1. <field name="value">Comunicació presentada a la Twenty-Fifth International Joint Conference on Artificial Intelligence, celebrada els dies 9 a 15 de juliol de 2016 a Nova York.</field>
      </element>
    2. <element name="abstract">
      1. <element name="en">
        <field name="value">Existentially quantified variables in goals and action preconditions are part of the standard PDDL planning language, yet few planners support them, while those that do compile them away at an exponential cost. In this work, we argue that existential variables are an essential feature for representing and reasoning with constraints in planning, and that it is harmful to compile them away or avoid them altogether, since this hides part of the problem structure that can be exploited computationally. We show how to do this by formulating an extension of the standard delete-relaxation heuristics that handles existential variables. While this extension is simple, the consequences for both modeling and computation are important. Furthermore, by allowing existential variables in STRIPS and treating them properly, CSPs can be represented and solved in a direct manner as action-less,fluent-less STRIPS planning problems, something important for problems involving restrictions. In addition, functional fluents in Functional STRIPS can be compiled away with no effect on the structure and informativeness of the resulting heuristic. Experiments are reported comparing our native ∃-STRIPS planner with state-of-the-art STRIPS planners over compiled and propositional encodings, and with a Functional STRIPS planner.</field>
        </element>
      </element>
    3. <element name="provenance">
      1. <element name="en">
        <field name="value">Made available in DSpace on 2018-03-12T10:49:54Z (GMT). No. of bitstreams: 1 Frances_IJCAI2016_stri.pdf: 576057 bytes, checksum: f1d269d70142e6eaa4c3464ae461bfda (MD5) Previous issue date: 2016</field>
        </element>
      </element>
    4. <element name="sponsorship">
      1. <element name="none">
        <field name="value">This work is partially supported by the M. de Maeztu Programme (MDM-2015-0502) and by grants TIN2015-67959 and CSD2010-00034, MEC, Spain.</field>
        </element>
      </element>
    </element>
  5. <element name="format">
    1. <element name="mimetype">
      1. <element name="none">
        <field name="value">application/pdf</field>
        </element>
      </element>
    </element>
  6. <element name="language">
    1. <element name="iso">
      1. <element name="none">
        <field name="value">eng</field>
        </element>
      </element>
    </element>
  7. <element name="publisher">
    1. <element name="ca">
      1. <field name="value">IJCAI & AAAI Press</field>
      </element>
    </element>
  8. <element name="relation">
    1. <element name="ispartof">
      1. <element name="none">
        <field name="value">Kambhampati S, editor. Twenty-Fifth International Joint Conference on Artificial Intelligence; 2016 Jul 9-15; New York, NY. Palo Alto (CA): AAAI Press / IJCAI; 2016. p. 3082-8.</field>
        </element>
      </element>
    2. <element name="projectID">
      1. <element name="none">
        <field name="value">info:eu-repo/grantAgreement/ES/1PE/TIN2015-67959</field>
        <field name="value">info:eu-repo/grantAgreement/ES/3PN/CSD2010-00034</field>
        </element>
      </element>
    </element>
  9. <element name="rights">
    1. <element name="none">
      1. <field name="value">Copyright © 2016 International Joint Conferences on Artificial Intelligence</field>
      </element>
    2. <element name="accessRights">
      1. <element name="none">
        <field name="value">info:eu-repo/semantics/openAccess</field>
        </element>
      </element>
    </element>
  10. <element name="subject">
    1. <element name="other">
      1. <element name="none">
        <field name="value">Intel·ligència artificial</field>
        </element>
      </element>
    </element>
  11. <element name="title">
    1. <element name="ca">
      1. <field name="value">∃-STRIPS: existential quantification in planning and constraint satisfaction</field>
      </element>
    </element>
  12. <element name="type">
    1. <element name="none">
      1. <field name="value">info:eu-repo/semantics/conferenceObject</field>
      </element>
    2. <element name="version">
      1. <element name="none">
        <field name="value">info:eu-repo/semantics/publishedVersion</field>
        </element>
      </element>
    </element>
  </element>
2. <element name="bundles">
  1. <element name="bundle">
    1. <field name="name">THUMBNAIL</field>
    2. <element name="bitstreams">
      1. <element name="bitstream">
        <field name="name">Frances_IJCAI2016_stri.pdf.jpg</field>
        <field name="originalName">Frances_IJCAI2016_stri.pdf.jpg</field>
        <field name="description">IM Thumbnail</field>
        <field name="format">image/jpeg</field>
        <field name="size">21257</field>
        <field name="url">http://repositori.upf.edu/bitstream/10230/34084/3/Frances_IJCAI2016_stri.pdf.jpg</field>
        <field name="checksum">4d2042155c2527f858d36b6aa551a94e</field>
        <field name="checksumAlgorithm">MD5</field>
        <field name="sid">3</field>
        </element>
      </element>
    </element>
  2. <element name="bundle">
    1. <field name="name">TEXT</field>
    2. <element name="bitstreams">
      1. <element name="bitstream">
        <field name="name">Frances_IJCAI2016_stri.pdf.txt</field>
        <field name="originalName">Frances_IJCAI2016_stri.pdf.txt</field>
        <field name="description">Extracted text</field>
        <field name="format">text/plain</field>
        <field name="size">39154</field>
        <field name="url">http://repositori.upf.edu/bitstream/10230/34084/2/Frances_IJCAI2016_stri.pdf.txt</field>
        <field name="checksum">90b7fcd31253344ab4496c090879f87e</field>
        <field name="checksumAlgorithm">MD5</field>
        <field name="sid">2</field>
        </element>
      </element>
    </element>
  3. <element name="bundle">
    1. <field name="name">ORIGINAL</field>
    2. <element name="bitstreams">
      1. <element name="bitstream">
        <field name="name">Frances_IJCAI2016_stri.pdf</field>
        <field name="format">application/pdf</field>
        <field name="size">576057</field>
        <field name="url">http://repositori.upf.edu/bitstream/10230/34084/1/Frances_IJCAI2016_stri.pdf</field>
        <field name="checksum">f1d269d70142e6eaa4c3464ae461bfda</field>
        <field name="checksumAlgorithm">MD5</field>
        <field name="sid">1</field>
        </element>
      </element>
    </element>
  </element>
3. <element name="others">
  1. <field name="handle">10230/34084</field>
  2. <field name="identifier">oai:repositori.upf.edu:10230/34084</field>
  3. <field name="lastModifyDate">2018-03-13 03:31:38.53</field>
  </element>
4. <element name="repository">
  1. <field name="name">Repositori digital de la UPF</field>
  2. <field name="mail">repositori@upf.edu</field>
  </element>
</metadata>