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            <front>

                <journal-meta>
                                    <journal-id></journal-id>
            <journal-title-group>
                                                                                    <journal-title>Hacettepe Journal of Mathematics and Statistics</journal-title>
            </journal-title-group>
                            <issn pub-type="ppub">2651-477X</issn>
                                        <issn pub-type="epub">2651-477X</issn>
                                                                                            <publisher>
                    <publisher-name>Hacettepe University</publisher-name>
                </publisher>
                    </journal-meta>
                <article-meta>
                                        <article-id pub-id-type="doi">10.15672/hujms.1285069</article-id>
                                                                <article-categories>
                                            <subj-group  xml:lang="en">
                                                            <subject>Mathematical Sciences</subject>
                                                    </subj-group>
                                            <subj-group  xml:lang="tr">
                                                            <subject>Matematik</subject>
                                                    </subj-group>
                                    </article-categories>
                                                                                                                                                        <title-group>
                                                                                                                        <article-title>Unique recovery of the initial state of distributed order time fractional diffusion equation</article-title>
                                                                                                                                        </title-group>
            
                                                    <contrib-group content-type="authors">
                                                                        <contrib contrib-type="author">
                                                                    <contrib-id contrib-id-type="orcid">
                                        https://orcid.org/0009-0008-8095-3245</contrib-id>
                                                                <name>
                                    <surname>Liu</surname>
                                    <given-names>Hui</given-names>
                                </name>
                                                                    <aff>Ningbo University</aff>
                                                            </contrib>
                                                    <contrib contrib-type="author">
                                                                    <contrib-id contrib-id-type="orcid">
                                        https://orcid.org/0000-0002-5961-7211</contrib-id>
                                                                <name>
                                    <surname>Li</surname>
                                    <given-names>Zhiyuan</given-names>
                                </name>
                                                                    <aff>Ningbo University</aff>
                                                            </contrib>
                                                    <contrib contrib-type="author">
                                                                    <contrib-id contrib-id-type="orcid">
                                        https://orcid.org/0000-0001-9024-8242</contrib-id>
                                                                <name>
                                    <surname>Ruan</surname>
                                    <given-names>Zhousheng</given-names>
                                </name>
                                                                    <aff>East China University of Technology</aff>
                                                            </contrib>
                                                                                </contrib-group>
                        
                                        <pub-date pub-type="pub" iso-8601-date="20241228">
                    <day>12</day>
                    <month>28</month>
                    <year>2024</year>
                </pub-date>
                                        <volume>53</volume>
                                        <issue>6</issue>
                                        <fpage>1560</fpage>
                                        <lpage>1574</lpage>
                        
                        <history>
                                    <date date-type="received" iso-8601-date="20230418">
                        <day>04</day>
                        <month>18</month>
                        <year>2023</year>
                    </date>
                                                    <date date-type="accepted" iso-8601-date="20231118">
                        <day>11</day>
                        <month>18</month>
                        <year>2023</year>
                    </date>
                            </history>
                                        <permissions>
                    <copyright-statement>Copyright © 2002, Hacettepe Journal of Mathematics and Statistics</copyright-statement>
                    <copyright-year>2002</copyright-year>
                    <copyright-holder>Hacettepe Journal of Mathematics and Statistics</copyright-holder>
                </permissions>
            
                                                                                                <abstract><p>We use Phragmén-Lindelöf-Liouville argument to prove the uniqueness for the determining the initial state of solution for the time fractional diffusion equation with distributed order derivative.  Several numerical experiments are presented to show the accuracy and efficiency of the algorithm.</p></abstract>
                                                                                    
            
                                                            <kwd-group>
                                                    <kwd>ultraslow diffusion</kwd>
                                                    <kwd>  inverse problem</kwd>
                                                    <kwd>  regularization method</kwd>
                                            </kwd-group>
                                                        
                                                                                                                                                <funding-group specific-use="FundRef">
                    <award-group>
                                                    <funding-source>
                                <named-content content-type="funder_name">National Natural Science Foundation of China</named-content>
                            </funding-source>
                                                                            <award-id>12271277; 12061008</award-id>
                                            </award-group>
                </funding-group>
                                </article-meta>
    </front>
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