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<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Publishing DTD v1.0 20120330//EN" "JATS-journalpublishing1.dtd"><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" article-type="research-article"><front><journal-meta><journal-id journal-id-type="publisher-id">INFORMATICA</journal-id><journal-title-group><journal-title>Informatica</journal-title></journal-title-group><issn pub-type="epub">0868-4952</issn><issn pub-type="ppub">0868-4952</issn><publisher><publisher-name>VU</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">inf14307</article-id><article-id pub-id-type="doi">10.15388/Informatica.2003.027</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research article</subject></subj-group></article-categories><title-group><article-title>Absolute Stability of Single‐Input Single‐Output Systems with Constant Internal Point Time Delays</article-title></title-group><contrib-group><contrib contrib-type="Author"><name><surname>de la Sen</surname><given-names>Manuel</given-names></name><email xlink:href="mailto:msen@we.lc.ehu.es">msen@we.lc.ehu.es</email><xref ref-type="aff" rid="j_INFORMATICA_aff_000"/></contrib><aff id="j_INFORMATICA_aff_000">Instituto de Investigación y Desarrollo de Procesos, Facultad de Ciencias, Universidad del Pais Vasco, Leioa (Bizkaia), Aptdo, 644 de Bilbao, 48080‐Bilbao, Spain</aff></contrib-group><pub-date pub-type="epub"><day>01</day><month>01</month><year>2003</year></pub-date><volume>14</volume><issue>3</issue><fpage>357</fpage><lpage>374</lpage><history><date date-type="received"><day>01</day><month>03</month><year>2003</year></date></history><abstract><p>This paper deals with the absolute stability of single‐input single‐output time‐delay systems with, in general, a finite number of non commensurate constant internal point delays for any nonlinearity satisfying a time positivity inequality related to the first and third quadrants. The results are obtained based on Lyapunov's stability analysis via appropriate Lyapunov's functions and the related stability study is performed to obtain both delay independent and delay dependent results.</p></abstract><kwd-group><label>Keywords</label><kwd>absolute stability</kwd><kwd>dynamic systems</kwd><kwd>nonlinear feedback</kwd><kwd>time‐delay systems</kwd></kwd-group></article-meta></front></article>