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            <front>

                <journal-meta>
                                                                <journal-id>jaem</journal-id>
            <journal-title-group>
                                                                                    <journal-title>TWMS Journal of Applied and Engineering Mathematics</journal-title>
            </journal-title-group>
                            <issn pub-type="ppub">2146-1147</issn>
                                        <issn pub-type="epub">2587-1013</issn>
                                                                                            <publisher>
                    <publisher-name>Işık University Press</publisher-name>
                </publisher>
                    </journal-meta>
                <article-meta>
                                        <article-id/>
                                                                <article-categories>
                                            <subj-group  xml:lang="en">
                                                            <subject>Combinatorics and Discrete Mathematics (Excl. Physical Combinatorics)</subject>
                                                    </subj-group>
                                            <subj-group  xml:lang="tr">
                                                            <subject>Kombinatorik ve Ayrık Matematik (Fiziksel Kombinatorik Hariç)</subject>
                                                    </subj-group>
                                    </article-categories>
                                                                                                                                                        <title-group>
                                                                                                                        <article-title>$S_{4}$ SEPARATION AND P-PARTITION IN ALL-PATH AND DETOUR CONVEXITIES</article-title>
                                                                                                    </title-group>
            
                                                    <contrib-group content-type="authors">
                                                                        <contrib contrib-type="author">
                                                                    <contrib-id contrib-id-type="orcid">
                                        https://orcid.org/0009-0001-1064-2512</contrib-id>
                                                                <name>
                                    <surname>Haponenko</surname>
                                    <given-names>Vladyslav</given-names>
                                </name>
                                                                    <aff>National University of Kyiv-Mohyla Academy &amp; Kyiv School of Economics</aff>
                                                            </contrib>
                                                                                </contrib-group>
                        
                                        <pub-date pub-type="pub" iso-8601-date="20260407">
                    <day>04</day>
                    <month>07</month>
                    <year>2026</year>
                </pub-date>
                                        <volume>16</volume>
                                        <issue>4</issue>
                                        <fpage>443</fpage>
                                        <lpage>456</lpage>
                        
                        <history>
                                    <date date-type="received" iso-8601-date="20250306">
                        <day>03</day>
                        <month>06</month>
                        <year>2025</year>
                    </date>
                                                    <date date-type="accepted" iso-8601-date="20250730">
                        <day>07</day>
                        <month>30</month>
                        <year>2025</year>
                    </date>
                            </history>
                                        <permissions>
                    <copyright-statement>Copyright © 2010, TWMS Journal of Applied and Engineering Mathematics</copyright-statement>
                    <copyright-year>2010</copyright-year>
                    <copyright-holder>TWMS Journal of Applied and Engineering Mathematics</copyright-holder>
                </permissions>
            
                                                                                                <abstract><p>In this work, we consider problems of $S_{4}$ and $p$-convex partition separations with respect to the all-path and the detour convexities. We give characterizations of $p$-all-path convex and $p$-detour convex graphs. With respect to all-path convexity $S_{2}$, $S_{3}$, and $S_{4}$ separable graphs are characterized. Also, we present necessary and sufficient conditions for two sets to be $S_{4}$ separable, for both convexities. Moreover, we prove that in all-path convexity the time complexity of those problems is linear, and it is NP-hard for detour convexity. Finally, we give an algorithm for determining whether two sets in graph are $S_{4}$ separable with respect to all-path convexity.</p></abstract>
                                                            
            
                                                            <kwd-group>
                                                    <kwd>all-path convexity</kwd>
                                                    <kwd>  graph convexity</kwd>
                                                    <kwd>  detour convexity</kwd>
                                                    <kwd>  convex separation</kwd>
                                                    <kwd>  $p$-partition</kwd>
                                            </kwd-group>
                            
                                                                                                                        </article-meta>
    </front>
    <back>
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    </article>
