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        <h1><a href="index.html"><span class="logo_colour">Svajūnas Sajavičius</span></a></h1>
		<h2>Associate Professor @ Kaunas University of Technology</h2>
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        <h1>Research interests</h1>
        <ul>
            <li>Discretization methods for PDEs (isogeometric analysis, meshless methods)</li>
            <li>Computer aided geometric design (applications in isogeometric analysis)</li>
        </ul>

        <h1>Publications</h1>
        <h2>Submitted preprints</h2>
        <ol reversed>
            <li>S. Sajavičius. AdagradLSPIA: Integrating adaptive optimization into least squares progressive iterative approximation, 2025. <a href="https://doi.org/10.48550/arXiv.2501.10170" target="_blank">https://doi.org/10.48550/arXiv.2501.10170</a> <a href="https://arxiv.org/abs/2501.10170" target="_blank">[arXiv:2501.10170]</a></li>
	</ol>
	      
        <h2>Journal publications</h2>
        <ol reversed>
            <li>S. Sajavičius. Hyperpower least squares progressive iterative approximation. <em>Journal of Computational and Applied Mathematics</em>, <strong>422</strong>, 2023, 114888. <a href="https://doi.org/10.1016/j.cam.2022.114888" target="_blank">https://doi.org/10.1016/j.cam.2022.114888</a> [<a href="https://bit.ly/3NBk8G2" target="_blank">Download&nbsp;PDF</a>]</li>
	    <li>S. Sajavičius, T. Takacs. Imposing nonlocal boundary conditions in Galerkin-type methods based on non-interpolatory functions. <em>Computers and Mathematics with Applications</em>, <strong>80</strong>(12), 2020, pp. 2877–2895. <a href="https://doi.org/10.1016/j.camwa.2020.09.016" target="_blank">https://doi.org/10.1016/j.camwa.2020.09.016</a> [<a href="https://www.sciencedirect.com/science/article/pii/S0898122120303783/pdfft?md5=fb2fe224afd6c39a2d422778736e531a&pid=1-s2.0-S0898122120303783-main.pdf" target="_blank">Download&nbsp;PDF</a>]</li>
            <li>J. Mart&iacute;n-Vaquero, S. Sajavičius. The two-level finite difference schemes for the heat equation with nonlocal initial condition. <em>Applied Mathematics and Computation</em>, <strong>342</strong>, 2019, pp. 166–177. <a href="https://doi.org/10.1016/j.amc.2018.09.025" target="_blank">https://doi.org/10.1016/j.amc.2018.09.025</a> [<a href="files/papers/Martin-Vaquero_Sajavicius_2019a_Appl_Math_Comput.pdf" target="_blank">Download&nbsp;PDF</a>]</li>
            <li>S. Sajavičius. Radial basis function collocation method for an elliptic problem with nonlocal multipoint boundary condition. <em>Engineering Analysis with Boundary Elements</em>, <strong>67</strong>, 2016, pp. 164–172. <a href="https://doi.org/10.1016/j.enganabound.2016.03.010" target="_blank">https://doi.org/10.1016/j.enganabound.2016.03.010</a> [<a href="files/papers/Sajavicius_2016a_Eng_Anal_Bound_Elem.pdf" target="_blank">Download&nbsp;PDF</a>]</li>
            <li>S. Sajavičius. Radial basis function method for a multidimensional linear elliptic equation with nonlocal boundary conditions. <em>Computers and Mathematics with Applications</em>, <strong>67</strong>(7), 2014, pp. 1407–1420. <a href="https://doi.org/10.1016/j.camwa.2014.01.014" target="_blank">https://doi.org/10.1016/j.camwa.2014.01.014</a> [<a href="https://www.sciencedirect.com/science/article/pii/S0898122114000261/pdfft?md5=729cb1e50aa41f8d6d0b1d600af48101&pid=1-s2.0-S0898122114000261-main.pdf" target="_blank">Download&nbsp;PDF</a>]</li>
            <li>S. Sajavičius. Optimization, conditioning and accuracy of radial basis function method for partial differential equations with nonlocal boundary conditions—A case of two-dimensional Poisson equation. <em>Engineering Analysis with Boundary Elements</em>, <strong>37</strong>(4), 2013, pp. 788–804. <a href="https://doi.org/10.1016/j.enganabound.2013.01.009" target="_blank">https://doi.org/10.1016/j.enganabound.2013.01.009</a> [<a href="files/papers/Sajavicius_2013b_Eng_Anal_Bound.pdf" target="_blank">Download&nbsp;PDF</a>]</li>
            <li>S. Sajavičius. Stability of the weighted splitting finite-difference scheme for a two-dimensional parabolic equation with two nonlocal integral conditions. <em>Computers and Mathematics with Applications</em>, <strong>64</strong>(11), 2012, pp. 3845-3899. DOI: <a href="https://doi.org/10.1016/j.camwa.2012.08.009" target="_blank">https://doi.org/10.1016/j.camwa.2012.08.009</a> [<a href="https://www.sciencedirect.com/science/article/pii/S0898122112005445/pdfft?md5=5736b63666ca85152f1b5e835253c898&pid=1-s2.0-S0898122112005445-main.pdf" target="_blank">Download&nbsp;PDF</a>] </li>
            <li>S. Sajavičius. On the eigenvalue problems for differential operators with coupled boundary conditions.<em> Nonlinear Analysis: Modelling and Control</em>, <strong>15</strong>(4), 2010, pp. 493-500. <a href="https://doi.org/10.15388/NA.15.4.14320" target="_blank">https://doi.org/10.15388/NA.15.4.14320</a> [<a href="http://www.journals.vu.lt/nonlinear-analysis/article/download/14320/13208/" target="_blank">Download&nbsp;PDF</a>]</li>
            <li>S. Sajavičius. On the eigenvalue problems for finite-difference operators with coupled boundary conditions. <em>Šiauliai Mathematical Seminar</em>, <strong>5</strong>(<strong>13</strong>), 2010, pp. 87-100 [<a href="https://web.archive.org/web/20180421063738/http://siauliaims.su.lt/pdfai/2010/Saja-2010.pdf" target="_blank">Download&nbsp;PDF</a>]</li>
            <li>S. Sajavičius, M. Sapagovas. Numerical analysis of the eigenvalue problem for one-dimensional differential operator with nonlocal integral conditions. <em>Nonlinear Analysis: Modelling and Control</em>, <strong>14</strong>(1), 2009, pp. 115-122. <a href="https://doi.org/10.15388/NA.2009.14.1.14535" target="_blank">https://doi.org/10.15388/NA.2009.14.1.14535</a> [<a href="http://www.journals.vu.lt/nonlinear-analysis/article/download/14535/13462/" target="_blank">Download&nbsp;PDF</a>]</li>
        </ol>

        <h2>Book chapter</h2>
        <ol reversed>
            <li>S. Sajavičius, B.Jüttler, J. Špeh. Template mapping using adaptive splines and optimization of the parameterization. In: C. Giannelli and  H. Speleers (eds.)  <em><a href="https://www.springer.com/book/9783030273309" target="_blank">Advanced Methods for Geometric Modeling and Numerical Simulation</a></em>, Springer INdAM series, Vol. 35, pp. 217–238, Springer, Cham, 2019. <a href="https://doi.org/10.1007/978-3-030-27331-6_9" target="_blank">https://doi.org/10.1007/978-3-030-27331-6_9</a> [<a href="http://gs.jku.at/pubs/NFNreport78.pdf" target="_blank">Download&nbsp;PDF</a>]</li>
        </ol>
        
        <h2>Conference publications</h2>
        <ol reversed>
            <li>S. Sajavičius. The splitting finite-difference scheme for two-dimensional heat conduction equation with four nonlocal integral conditions. In: J. Eberhardsteiner, H. J. Böhm, F. G. Rammerstorfer (eds.) <em>CD-ROM Proceedings of the 6th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012), Vienna, Austria, September 10–14, 2012, CD-ROM</em>, Paper ID 1081, 12 p., Vienna, Austria, 2012.</li>
            <li>S. Sajavičius. On the stability of fully-explicit finite-difference scheme for two-dimensional parabolic equation with nonlocal conditions. In: B. Murgante, O. Gervasi, A. Iglesias, D. Taniar, B. O. Apduhan (eds.) <em>Computational Science and Its Applications &#8211; ICCSA 2011, International Conference, Santander, Spain, June 20-23, 2011, Proceedings, Part IV. Lecture Notes in Computer Science</em>, <strong>6785</strong>, pp. 1-10, Springer-Verlag Berlin Heidelberg, 2011. <a href="https://doi.org/10.1007/978-3-642-21898-9_1" target="_blank">https://doi.org/10.1007/978-3-642-21898-9_1</a></li>
            <li>S. Sajavičius. On the stability of locally one-dimensional method for two-dimensional parabolic equation with nonlocal integral conditions. In: J. C. F. Pereira, A. Pereira, J. M. C. Sequeira  (eds.) <em>Proceedings of the V European Conference on Computational Fluid Dynamics (ECCOMAS CFD 2010)</em>, Paper ID 01668, 11 p., Lisbon, Portugal, 2010.</li>
            <li>S. Sajavičius. On the stability of alternating direction method for two-dimensional parabolic equation with nonlocal integral conditions. In: V. Kleiza, S. Rutkauskas, A. Štikonas (eds.) <em>Proceedings of International Conference Differential Equations and Their Applications (DETA 2009)</em>, pp. 42-48, Technologija, Kaunas, Lithuania, 2009.</li>
        </ol>

        <h2>Technical reports</h2>
        <ol reversed>
            <li>S. Sajavičius, B.Jüttler and J. Špeh. Template mapping using adaptive splines and optimization of the parameterization. <em>NFN Technical Report No. 78</em>, 2019 [<a href="http://gs.jku.at/pubs/NFNreport78.pdf" target="_blank">Download&nbsp;PDF</a>]</li>
            <li>Optimization framework integrating the volumetric approaches, adaptive refinement procedures and the new shape deformation techniques. <em>MOTOR Project D5.2</em>, 2018 [Confidential]</li>
            <!-- <li>Report on shape deformation techniques based on volumetric approaches. <em>MOTOR Project D2.4</em>, 2018 [<a href="http://motor-project.eu/wp-content/uploads/2018/08/MOTOR_D2.4.pdf" target="_blank">Download PDF</a>]<br/></li>-->
            <li>Report on shape deformation techniques based on volumetric approaches. <em>MOTOR Project D2.4</em>, 2018 [<a href="https://ec.europa.eu/research/participants/documents/downloadPublic?documentIds=080166e5bc6b857b&appId=PPGMS" target="_blank">Download&nbsp;PDF</a>]<br/></li>
            <!-- <li>Report and prototype software for geometry-aware block structuring and volume parameterization <em>MOTOR Project D2.3</em>, 2017 [<a href="http://motor-project.eu/wp-content/uploads/2017/09/MOTOR_D2.3.pdf" target="_blank">Download PDF</a>]<br/></li>-->
            <li>Report and prototype software for geometry-aware block structuring and volume parameterization <em>MOTOR Project D2.3</em>, 2017 [<a href="https://ec.europa.eu/research/participants/documents/downloadPublic?documentIds=080166e5b4cbe817&appId=PPGMS" target="_blank">Download&nbsp;PDF</a>]<br/></li>
            <!-- <li>Report and prototype software for multivariate adaptive spline technology. <em>MOTOR Project D2.1</em>, 2016 [<a href="http://motor-project.eu/wp-content/uploads/2016/10/MOTOR_D2.1.pdf" target="_blank">Download PDF</a>]<br/></li>-->
            <li>Report and prototype software for multivariate adaptive spline technology. <em>MOTOR Project D2.1</em>, 2016 [<a href="https://ec.europa.eu/research/participants/documents/downloadPublic?documentIds=080166e5acd8dc04&appId=PPGMS" target="_blank">Download&nbsp;PDF</a>]<br/></li>
        </ol>

        <h2>Extended abstracts</h2>
        <ol reversed>
            <li>S. Sajavičius. The splitting finite-difference schemes for two-dimensional parabolic equation with nonlocal weighted integral conditions. In: S. Repin, T. Tiihonen, T. Tuovinen (eds.) <em>Proceedings of ECCOMAS Thematic Conference on Computational Analysis and Optimization (ECCOMAS CAO 2011)</em>, pp. 81–84, Jyväskylä, Finland, 2011.</li>
            <li>S. Sajavičius. The splitting finite-difference schemes for two-dimensional parabolic equation with nonlocal conditions. In:  A. Eriksson and G. Tibert (eds.) <em>Proceedings of NSCM23: the 23rd Nordic Seminar on Computational Mechanics / Technical report 2010:07</em>, pp. 345-348, Stockholm, Sweden, 2010.</li>
            <li>S. Sajavičius. The stability of alternating direction method for two-dimensional parabolic equation with nonlocal integral conditions. In: E. Lund, L. Damkilde, A. S. Andersen, E. Kristensen (eds.) <em>DCE Technical Memorandum No. 11 / Proceedings of the Twenty Second Nordic Seminar on Computational Mechanics</em>, pp. 87-90, Aalborg, Denmark, 2009.</li>
        </ol>
        
        <h1>Participation in international conferences</h1>
        <ul>
            <li><a href="http://iga2020.usacm.org/" target="_blank">Virtual Isogeometric Analysis 2020 (VIGA 2020)</a>, August 11–12, 2020 (online)</li>
            <li><a href="http://www.iciam2019.com/" target="_blank">9th International Congress on Industrial and Applied Mathematics (ICIAM 2019)</a>, 15–19 July, 2019, Valencia, Spain</li>
            <li><a href="http://www.mn.uio.no/MMCS9/" target="_blank">9th International Conference on Mathematical Methods for Curves and Surfaces (MMCS9)</a>, 23–28 June, 2016, Tønsberg, Norway</li>
            <li><a href="http://equadiff.zcu.cz/" target="_blank">Equadiff'13 conference</a>, 26–30 August, 2013, Prague, Czech Republic</li>
            <li><a href="http://congress.cimne.com/metnum2013/eng/" target="_blank">Congress on Numerical Methods in Engineering (CMN 2013)</a>, 25–28 June, 2013, Bilbao, Spain</li>
            <li><a href="http://eccomas2012.conf.tuwien.ac.at/" target="_blank">6th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012)</a>, 10–14 September, 2012, Vienna, Austria</li>
            <li><a href="http://amat2012.etu.edu.tr/" target="_blank">International Conference on Applied Mathematics and Approximation Theory (AMAT2012)</a>, 17–20 May, 2012, Ankara, Turkey</li>
            <li><a href="http://www.iciam2011.com/" target="_blank">7th International Congress on Industrial and Applied Mathematics (ICIAM 2011)</a>, 18–22 July, 2011, Vancouver, BC, Canada</li>
            <!--<a href="http://www.mit.jyu.fi/CAO2011/" target="_blank"><i>ECCOMAS Thematic Conference Computational Analysis and Optimization</i></a>, 9–11 July, 2011, Jyväskylä, Finland--><!--<a href="http://www.iccsa.org/"  target="_blank"><i>International Conference on Computational Science and Its Applications (ICCSA 2011)</i></a>, 20–23 June, 2011, Santander, Spain-->
            <li><a href="http://mma2011.lu.lv/" target="_blank">16th International Conference Mathematical Modelling and Analysis</a>, 25–28 May, 2011, Sigulda, Latvia</li>
            <li><a href="http://congress.cimne.com/nscm-23/frontal/default.asp"  target="_blank">23rd Nordic Seminar on Computational Mechanics</a>, 21–22 October, 2010, Stockholm, Sweden</li>
            <li><a href="http://www.eccomas-cfd2010.org" target="_blank">V European Conference on Computational Fluid Dynamics (ECCOMAS CFD 2010)</a>, 14–17 June, 2010, Lisbon, Portugal</li>
            <li><a href="http://inga.vgtu.lt/~art/konf/" target="_blank">15th International Conference Mathematical Modelling and Analysis</a>, 26–29 May, 2010, Druskininkai, Lithuania</li>
            <li><a href="http://www.civil.aau.dk/nscm22/" target="_blank">22nd Nordic Seminar on Computational Mechanics</a>, 22–23 October, 2009, Aalborg, Denmark</li>
            <li><i>International Conference Differential Equations and Their Applications dedicated to Professor M. Sapagovas 70th  anniversary</i>, 10–12 September, 2009, Panevėžys, Lithuania</li>
            <li><a href="http://www.de.dau.lv/mma2009/" target="_blank">14th International Conference Mathematical Modelling and Analysis</a>, 27–30 May, 2009, Daugavpils, Latvia</li>
        </ul>      
        
        <h1>Projects</h1>
        <ul>
            <li><a href="https://web.archive.org/web/20180723152319/http://motor-project.eu/" target="_blank">MOTOR – Multi-ObjecTive design Optimization of fluid eneRgy machines</a> (funded by European Commission through Horizon 2020 programme, project reference: 678727), 2015–2018
            <div align="center">
                <a href="https://web.archive.org/web/20180723152319/http://motor-project.eu/" target="_blank"><img alt="" style="max-width: 75%;" src="https://web.archive.org/web/20180830110116if_/http://motor-project.eu/wp-content/uploads/2015/11/MOTOR-Logo-Colour-CMYK.png"/></a>
            </div>
            More information: <a href="https://cordis.europa.eu/project/rcn/198350/" target="_blank">CORDIS</a>
            </li>            
            <li>
            <div class="hover_img_top">
                <a href="http://www.balticgrid.org/" target="_blank">BalticGrid-II project<img src="style/icons8-diploma-40.png" width="18px" align="top"/><span><img src="files/certificates/Certificate_2010_Apr_BalticGrid.jpg" alt="image" width="613px" /></span></a> (funded by the EU within the framework of the 7th Framework Programme, Contract No. 223807), 2010
            </div>
            </li>
            <li>Development of Bioelectrocatalysis for Synthesis and Analysis (BIOSA), #N–08007, Lithuanian State Science and Studies Foundation, 2008</li>
            <li>Computer Simulation of the Behavior of Heterogeneous Processes and Systems (MODELITA), #C–03048, Lithuanian State Science and Studies Foundation, 2005, 2006</li>
        </ul>     
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