# Yuriy Yashchuk

Position: Associate Professor, Applied Mathematics Department

Scientific degree: Candidate of Physical and Mathematical Sciences

Phone (office): (032) 239-43- 23

Email: yuriy.yashchuk@lnu.edu.ua

## Research interests

Mainly introducing and developing mesh adaptation algorithms in boundary and finite element methods. Ph. D. thesis concerns comparison of FEM and BEM results with the aim of obtaining error estimation and constructing h-adaptive schemes.

## Courses

## Publications

- Dyyak I. Combined Algorithm of Domain Decomposition and h -Adaptation for the Solution of Contact Problems of Elasticity / I. Dyyak, I. Prokopyshyn, Yu. Yashchuk // Journal of Mathematical Sciences. – 2015. – 208(4). – P. 383-399.

2. Dyyak I. Domain decomposition adaptivity schemes for contact problems of laminated composites / I. Dyyak, S. Matysiak, I. Prokopyshyn, Yu. Yashchuk // Conference Proceedings. VII-th International Symposium on Mechanics of Materials and Structures. June 3-6, 2013. – Augustow, Poland, 2013. – P. 59.

3. Dyyak I. FEM-BEM based error estimator in elasticity problems / I. Dyyak, S. Matysiak, Yu. Yashchuk // 19th International Conference on Computer Methods in Mechanics. Short Papers. – Warszawa: Warsaw University of Technology, 2011. – P. 175-176.

4. Dyyak I. Investigation of stress error estimator in elasticity problems / I. Dyyak, Yu. Yashchuk // Сontemporary problems of mathematics, mechanics and computing sciences. Editors N.N.Kizilova, G.N.Zholtkevych. – Kharkov: Apostrof, 2011. – P. 33-43.

5. Dyyak I. The error estimation for elasticity problems / I. Dyyak, Yu. Yashchuk, A. Torskyy // VIII International Conference Porous Materials & Symposium “Mathematical Modeling and Optimization in Mechanics”. Extend Abstracts – Lviv-Briukhovychi, 2011. – P.41.

In Ukrainian

6. Dyyak I. Adaptive heterogeneous numerical schemes via domain decompositions methods / I. Dyyak, I. Makar, I. Prokopyshyn, M Shahin, Yu Yashchuk // Papers of XXI national scientific conference “Contemporary problems of applied mathematics and informatics”. – Lviv, 2016. – P. 31-33.

7. Dyyak I. Adaptive scheme of finite-boundary element solving of elasticity problems / І. Dyyak, Yu. Yashchuk // VIII International scientific conference “Mathematical problems of inhomogeneous structutes”. Conference materials. – Lviv: Pidstrygach IAPMM NAS of Ukraine, 2010. – P. 27-28.

8. Dyyak I. Investigation of aposteriori finite element error estimator using boundary element method / I. Dyyak, I. Makar, Yu. Yashchuk // Reports of National scientific conference “Contemporary problems of mathematical modeling and numerical methods”. – Rivne, 2013. – P. 67.

9. Dyyak I. Study and application of finite-boundary element error estimator / І. Dyyak, Yu. Yashchuk // VI Lyashko International scientific conference “Numerical and applied mathematics”. – Kyiv, 2013. – P. 115.

10. Dyyak I. Construction and investigation of numerical solutions of elasticity problems based on h-adaptive approximations / І. Dyyak, І. Makar, Yu. Yashchuk // Mathematical and computer modeling. Physics and mathematics series. – Ogienko national university of Kamyanets-Podilskyy, 2010. – Vol. 4. – P. 76-85.

11. Dyyak I. Construction of h-adaptive schemes of finite element method for elasticity problems / І. Dyyak, Ya. Savula, Yu. Yashchuk // Physical and mathematical modeling and information technologies. – 2011. – Vol. 13. – P. 60-66.

12. Dyyak I. About local stress errors in terms of construction of finite element adaptive schemes for elasticity problems / І. Dyyak, Yu. Yashchuk // Mathematical modeling of complex systems. Papers of scientific conference. – Lviv, 2009. – P. 41.

13. Dyyak I. Finite- boundary element error estimator for elasticity problems / І. Dyyak, Yu. Yashchuk // Visnyk of Lviv University. Series applied mathematics and informatics. – 2013. – Vol. 19. – P. 47-55.

14. Dyyak I. Numerical solution of construction mechanics problem using mortar FEM / І. Dyyak, Ya. Savula, Yu. Yashchuk, А. Styahar // Mathematical modeling and mathematical physics. Reports. – Ostrogradskyy National University of Kremenchuk, 2011. – P. 32-33.

15. Dyyak I. Combined algorithm of domain decomposition and h-adaptation for solving elastic contact problems / I. Dyyak, I. Prokopyshyn, Yu. Yashchuk // Mathematical methods and physicomechanical fields. – Vol. 56. – No. 4. – P. 96-109.

16. Prokopyshyn І. Solving of problems of contact of two elastic bodies using h- adaptive finite element method / І. Prokopyshyn, Yu. Yashchuk // Papers of XIX national scientific conference “Contemporary problems of applied mathematics and informatics”. – Lviv, 2013. – P. 113.

17. Yashchuk Yu. Adaptive algorithm of numerical investigation of elasticity problem // Visnyk of Lviv University. Series applied mathematics and informatics. – 2010. – Vol. 16. – P. 96– 105.

18. Yashchuk Yu. Using BEM for elementwise error estimationі //Conference of young scientists and specialists “Contemporary problems of engineering”. Reports. – Kharkiv: Pidgornyy Institute of Engineering, 2012. – P. 47.

19. Yashchuk Yu. Utilizing nonconforming finite element approximations in modeling of elasticity problems // Conference of young scientists and specialists “Contemporary problems of engineering”. Reports. – Kharkiv: Pidgornyy Institute of Engineering, 2011. – P. 43.

20. Yashchuk Yu. Local stress errors generated by mortar functions utilization in finite element grid adaptation // Papers of XVI national scientific conference “Contemporary problems of applied mathematics and informatics”. – Lviv, 2009. – P. 235-236.

21. Yashchuk Yu. Construction of adaptive algorithm of solving elasticity problems using mortar functions // IV Conference of young scientists on contemporary problems of mechanics and mathematics. Reports. – Lviv: Pidstrygach IAPMM, 2011. – P. 27-28.

22. Yashchuk Yu. Theoretical aspects of construction of FEM error estimator in elasticity problems // Contemporary problems of mechanics and mathematics. Scientific digest. Vol 3. – Lviv, 2013. – P. 70-72.

23. Yashchuk Yu. h-adaptive scheme of boundary element method for solving 2D elasticity problem // XIII National student scientific conference on applied mathematics and informatics SSCAMI-2010. Proceedings. – Lviv, 2010. – P. 133-134.

24. Yashchuk Yu. h-adaptive scheme of numerical solving of elasticity problem // Computer sciences and engineering: Proceedings of IV International conference of young scientists CSE-2010. – Lviv, 2010. – P. 258-259.

In Russian

25. Yashchuk Yu. Solving of contact mechanics problem using h-adaptive finite

element method / Yu. Yashchuk, I. Prokopyshyn // Siberian electronic mathematical reports. – 2014. – Vol. 11. – P. 220-228.

## Biography

2007 – B.Sc. in Applied Mathematics (with Honors), Ivan Franko National University of Lviv.

2008 – M.Sc. in Applied Mathematics (with Honors), Ivan Franko National University of Lviv.

2014 – Ph.D. in Mathematical Modelling and Numerical Methods, Pidstryhach Institute for Applied Problems of Mechanics and Mathematics, National Academy of Sciences of Ukraine.

Working Experience

Since 2015 – Associate Professor at Department of Applied Mathematics, Ivan Franko National University of Lviv.

Giving studies in different courses:

• Software development: .NET Framework, C# language, Windows Forms, WPF.

• .NET technologies: ASP.NET MVC, Entity Framework.

• Databases: designing databases, basics of Structured Query Language, Microsoft Access, Microsoft SQL Server.

2010-2015 – Assistant Professor at Department of Applied Mathematics, Ivan Franko National University of Lviv.

Conducting laboratory and seminar classes in Functional Analysis, Numerical methods of mathematical physics, Object-oriented programming, Software development, Numerical methods of mathematical physics.

2009-2011 – Junior Scientific Worker at Ivan Franko National University of Lviv.

Developing finite element method (FEM) and boundary element method (BEM) based software in C# and Object Pascal (Delphi).

2008-2011 – Ph. D. Student at Ivan Franko National University of Lviv, specialty: mathematical modeling and computational methods.

Awards and Scholarships

2011 – Scholarship from Cosbild Fund (Canada) as a Ph. D. student.

April – May 2015 – Erasmus Mundus scholar-scholarship, University of L’Aquila (Italy).

2015 – Lviv regional award for talented young scientists (Ukraine).

June – September 2016 – 3-months scholarship as a visiting professor, University of L’Aquila (Italy).

2016 – President’s of Ukraine Award for Young Scientists.

January 2017 – One-month OeAD (Austrian agency for international mobility and cooperation in education, science and research) scholarship for research in Vienna Technical University.

Supervising

Master Thesis: Natalia Tycejko “Online resource for finite element modelling of heat transfer processes with aposteriori error estimation”, 2013.

Local project: Victoria Volyanska, Andriy Havrylyak “Interactive university navigation service”.

Volyanska V. Interactive university navigation service / V. Volyanska, A. Havrylyak // XIV International student scientific conference on Applied Mathematics and Informatics “SSCAMI-2016”. Conference materials. – Lviv: Ivan Franko National University of Lviv, 2016. – P. 16-17.

Other Information

Since 2015 – Executive Coordinator of Double Degree Master Program in Applied and Interdisciplinary Mathematics (“InterMaths”, http://intermaths.eu) from Ukrainian side: co-developing agreements and study plans; ranking and selection.

Since 2012 – Scientific Secretary of the Department of Applied Mathematics, Ivan Franko National University of Lviv.