WEEK OF MATHEMATICS AND INFORMATICS 2024

Sunday, September 22

Arrival day

16:00 -- 18:00 Registration of participants

Monday, September 23

08:00 -- 09:00 Registration of participants

Plenary hall

09:00 -- 09:30 Opening
09:30 -- 10:00 Invited talk: 135 years Faculty of Mathematics and Informatics: Origins and yearly development

Tinko Tinchev

Section: Variational Analysis and Applications

Chair: Mikhail Krastanov

10:00 -- 10:50 Invited talk: On second order sufficient condition for a minimum

Alexander Ioffe
11:00 -- 11:30 Metric slopes

Nadia Zlateva, Milen Ivanov
11:30 -- 12:00 Dual-based methods for the exponential stabilization of nonlinear dynamical systems

Sabine Pickenhain
12:00 -- 12:30 A variational condition in optimal control problems

Mikhail Krastanov, Nadezhda Ribarska
12:30 -- 14:00 Lunch

Hall А

Section: Challenges of the Digital World Traditions and Innovative Solutions in Research and Education

Chair: Mariana Atanassova

14:00 -- 14:50 Invited talk: Generative AI for learning, teaching and research -- examples and tools

Slavi Stoyanov

Parallel sessions:

Hall А

Section: Variational Analysis and Applications

Chair: Vladimir Veliov

15:00 -- 15:30 Variational principles for monotone variational inequalities: The multivalued case

Pando Georgiev
15:30 -- 16:00 Differential inclusions and quasi-Lyapunov functions

Martin Ivanov, Mikhail Krastanov, Nadezhda Ribarska
16:00 -- 16:30 Coffee Break
16:30 -- 17:00 A continuous linear-quadratic optimal control problem under external disturbances

Mikhail Krastanov, Boyan Stefanov
17:00 -- 17:30 Simultaneous perturbed minimization of a convergent sequence of functions

Hristina Topalova, Nadia Zlateva
17:30 -- 18:00 Transversality and subtransversality of closed convex cones

Nadezhda Ribarska, Maria Tasheva

Hall B

Section: Challenges of the Digital World Traditions and Innovative Solutions in Research and Education

Chair: Mariana Atanassova

15:00 -- 15:30 Programming in elementary education in the context of building 21st century competencies

Georgi Hristov
15:30 -- 16:00 Digital learning environment for pre-laboratory activities of the students in chemical education

Tanya Monova, Oleg Konstantinov, Stefan Tsakovski
16:00 -- 16:30 Coffee Break
16:30 -- 17:00 Empathy and teamwork as successful approaches for digital media education

Oleg Konstantinov
17:00 -- 17:30 Online digital resources for mental health literacy and resilience as a priority of the Me_Heli-D project

Dafinka Miteva, Elitsa Peltekova, Ioannis Patias
17:30 -- 18:00 High school education approach to development of industrial robot that uses Artificial Intelligence

Ianislav Kartelov, Ivan Shepelev
19:30 -- 20:30 Welcome party

Tuesday, September 24

Parallel sessions

Hall A

Section: Algebra and coding theory

Dedicated to the memory of Kerope Tchakerian (1944 -- 2012)

Chair: Maya Stoyanova

09:00 -- 09:50 Invited talk: Optimal polarization (PULB) pairs of codes found in the Leech lattice

Sergiy Borodachov, Peter Boyvalenkov, Peter Dragnev, Douglas Hardin, Edward Saff, Maya Stoyanova
10:00 -- 10:30 A kissing number with forbidden distances

Peter Boyvalenkov, Danila Cherkashin
10:30 -- 11:00 Theorems of Erdos-Ko-Rado type in ring geometries

Ivan Landjev, Emiliyan Rogachev, Assia Rousseva
11:00 -- 11:30 Coffee break

Chair: Ivan Landjev

11:30 -- 12:00 Noncommutative alternating polynomials in free associative algebras

Silvia Boumova, Vesselin Drenski, Deyan Dzhundrekov, Martin Kassabov
12:00 -- 12:30 A Diophantine problem with two primes and a square of prime of a special form

Tatiana Todorova
12:30 -- 13:00 Divisors of codes

Azniv Kasparian
13:00 -- 14:00 Lunch

Section: Differential Equations and Applications

Chair: Virginia Kiriakova

14:00 -- 14:50 Invited talk: Pohožaev identities and some applications in nonlinear PDE

Nedyu Popivanov
15:00 -- 15:30 Fractional differential equations with the general fractional derivatives with the Sonin kernels

Yuri Luchko
15:30 -- 16:00 Semi-global symplectic invariant of the champagne bottle

Ognyan Christov
16:00 -- 16:30 Coffee break

Chair: Nedyu Popivanov

16:30 -- 17:00 Analytical properties and examples of the generalized Fox-Wright function

Jordanka Paneva-Konovska, Virginia Kiriakova
17:00 -- 17:30 Multidimensional Protter-Morawetz problems for degenerate hyperbolic equations

Tsvetan Hristov
17:30 -- 18:00 Non-integrability of the Sasano systems

Tsvetana Stoyanova

Hall B

Section: Information Science and e-Society (UNITe)

Chair: Evgeniy Krastev

09:30 -- 10:00 The Centre of excellence Unite in the Knowledge Triangle

Elissaveta Gourova
10:00 -- 10:30 Cross-modal data representation through vectorization: a case study with vector forge

Simeon Emanuilov, Aleksandar Dimov
10:30 -- 11:00 Neural networks for ovary diseases recognition

Yasmina Osmandzhikova, Sotir Sotirov
11:00 -- 11:30 Coffee break
11:30 -- 12:00 Machine learning reveals specific blood microbial profiles in pulmonary sarcoidosis patients

Maya Zhelyazkova, Y. Hodzhev, B. Tsafarova, V. Tolchkov, N. Yanev, V. Youroukova, S. Ivanova, D. Kostadinov, M. Nacheva-Sokolova, S. Tsonev, S. Panaiotov
12:00 -- 12:30 Investigation of the scalability of a parallel system based on the sieve of Eratosthenes

Dobromir Petrov, Stanislav Simeonov
12:30 -- 13:00 Advanced models for text summarization: A comparative study

Maria Nisheva
13:00 -- 14:00 Lunch

Section: Mechatronics and Robotics

Chair: Ivan Chavdarov

14:00 -- 14:30 Motion design of an open-chain redundant robot arm using factor group technique

George Boiadjiev, Ivan Chavdarov, Evgeniy Krastev, Lyubomira Miteva
14:30 -- 15:00 Nonlinear regression and sensitivity analysis for continuous approximation of TBP data for crude oils

Dimitar Nedanovski, Svetoslav Nenov
15:00 -- 15:30 Investigation of motion planning algorithms for a mobile robot under incomplete environmental information

Vasil Ninov, Ivan Chavdarov, Kaloyan Yovchev
15:30 -- 16:00 Design and control of 3D printed parallel robot with a delta structure

Vladislav Hrosinkov, Ivan Chavdarov, Kaloyan Yovchev
16:00 -- 16:30 Coffee break
16:30 -- 17:00 Enhancing the education in mathematics and informatics by using ROS (Robot operating system) for interdisciplinary projects

Simeon Tsvetanov, Albena Antonova
17:00 -- 17:30 Dynamical model and control of a simple 3D printed walking robot

Aleksander Stefanov, Ivan Chavdarov, Dimitar Nedanovski, Kaloyan Yovchev
19:30 Dinner

Wednesday, September 25

Parallel sessions

Hall А

Section: Numerical Methods and Theory of Approximations

Dedicated to the memory of Borislav Bojanov (1944 -- 2009)

Chair: Geno Nikolov

09:00 -- 09:50 Invited talk: Some remarks on the B-spline basis condition number

Alexei Shadrin
10:00 -- 10:30 Monotonicity and unimodality of ratios of integral transforms and applications

Dmitrii Karp, Anna Vishnyakova, Yi Zhang
10:30 -- 11:00 Chebyshev B-splines with Birkhoff-type of knots

Rumen Uluchev
11:00 -- 11:30 Coffee break

Chair: Rumen Uluchev

11:30 -- 12:00 On the regularity of some Birkhoff interpolation problems induced by three-row almost Hermitian incidence matrices

Geno Nikolov, Borislava Konstantinova
12:00 -- 12:30 Weighted approximation of functions in L_p-norm by Kantorovich modifications of some classical operators

Ivan Gadjev
13:00 -- 14:00 Lunch

Section: Variational Analysis and Applications

Chair: Nadya Zlateva

14:00 -- 14:50 Invited talk: Frechet versus Gateaux differentiability -- Counter-example

Marián Fabian, Jan Kolář
15:00 -- 15:30 An immuno-epidemiological model with dynamic immunity

Vladimir Veliov
15:30 -- 16:00 On the problem of calculus of variations with pure state constraints of equality type

Mikhail Krastanov
16:00 -- 16:30 Coffee break
16:30 -- 17:00 High-order small-time local controllability

Margarita Nikolova, Mikhail Krastanov
17:00 -- 17:30 Fixed Point Theorems in Premetric Spaces

Milen Ivanov, Detelina Kamburova, Nadia Zlateva

Hall B

Section: Differential Equations and Applications

Chair: Tsvetan Hristov

09:30 -- 10:00 Differential equations in vertex algebras and deformations

Nikolay M. Nikolov
10:00 -- 10:30 Role of dielectric permittivity on plasma behaviour in surface-wave discharge

Mariana Atanasova, A. Stefanov, E. Benova, J. J. A. M. van der Mullen
10:30 -- 11:00 Meromorphic non-integrability of a Hamiltonian system with a sixth-order homogeneous potential

Georgi Georgiev, Dessislava Neykova
11:00 -- 11:30 Coffee break
11:30 -- 12:00 On the uniqueness of the solutions of some non-local BV problems for second order linear PDE of changing type

Mariya Karatopraklieva
12:00 -- 12:30 Singular solutions to Protter's boundary-value problem for the wave equation

Todor Popov
12:30 -- 13:00 A continuous-time OLG model with human capital - exploring the interplay of qualification and demographic developments

Andrey Vassilev
13:00 -- 14:00 Lunch

Section: Numerical Methods and Theory of Approximations

Dedicated to the memory of Borislav Bojanov (1944 -- 2009)

Chair: Alexei Shadrin

14:00 -- 14:30 Fourier quasicrystals, crystalline measures and their generalizations

Serhii Favorov
14:30 -- 15:00 Multiclass approximation and subspace clustering in reproducing kernel Hilbert spaces

Pando Georgiev
15:00 -- 15:30 Instability analysis of a diffusion-reaction PDE model describing immune cell dynamics

Tihomir Ivanov, Georgi Bazlyankov
15:30 -- 16:00 Markov interlacing property for generalized polynomials

Lozko Milev, Nikola Naidenov
16:00 -- 16:30 On the critical points of oscillating polynomials with Laguerre weight

Lozko Milev, Nikola Naidenov
16:30 -- 17:00 Coffee break

Section: Probabilities and Statistics

Chair: Pando Georgiev

17:00 -- 17:30 Transformations of discrete stable process via branching reproduction of particles

Maroussia Slavtchova-Bojkova, Penka Mayster
17:30 -- 18:00 Modelling longitudinal cognitive test data with ceiling effects and left skewness

Denitsa Grigorova, Dean Palejev, Ralitza Gueorguieva
18:00 -- 18:30 Generalization of multitype branching processes with immigration generated by point processes

Martin Minchev, Maroussia Slavtchova-Bojkova
18:30 -- 19:00 Branching processes with random migration

Tsvetomira Zlatkova, Vessela Stoimenova

Hall C

Section: Challenges of the Digital World Traditions and Innovative Solutions in Research and Education

09:00 -- 11:00 Workshop: Digital competence in the (Future-Directed) University Curricula for teachers of mathematics and informatics

Nikolina Nikolova, Olga Firssova, Temenuzhka Zafirova-Malcheva, Borislava Videnova, Russi Kararusinov
11:00 -- 11:30 Coffee break
11:30 -- 13:00 Workshop: Modern-@ Masters' programs rethinking

Nikolina Nikolova, Olga Firssova, Temenuzhka Zafirova-Malcheva
13:00 -- 14:00 Lunch
14:00 -- 14:45 Workshop: Educational storytelling using generative AI & HI

Trayan Iliev
15:00 -- 16:00 Workshop: Interactive content creation: A beginner's guide to creating, sharing and reusing digital resources

Elitsa Peltekova
19:30 -- 22:00 Dinner

Thursday, September 26

Parallel sessions

Hall A

Section: Geometry and Topology

Chair: Peter Boyvalenkov

09:00 -- 09:50 Invited talk: 130+ Years of the Hadamard conjecture

Ilias Kotsireas

10:00 -- 10:30 The Riemannian curvature identities on almost complex Calabi-Yau with torsion 6-manifold and generalized Ricci solitons

Stefan Ivanov, Nikola Stanchev

10:30 -- 11:00 Li-Yau Sub-gradient estimates and Perelman-type entropy formulas for the heat equation in quaternionic contact geometry

Alexander Petkov

11:00 -- 11:30 Coffee break

Chair: Stefan Ivanov

11:30 -- 12:00 Geometry of paraquaternionic contact structures

Stefan Ivanov, Marina Tchomakova, Simeon Zamkovoy

12:00 -- 12:30 Nonlocal analogues of the Lidstone polynomials

Yulian Tsankov

12:30 -- 13:00 The Riemannian Bianchi identities of metric connections with skew torsion and generalized Ricci solitons

Stefan Ivanov, Nikola Stanchev

13:00 -- 14:00 Lunch

Section: Mathematical Logic and its Applications

Dedicated to the memory of Dimiter Vakarelov (1938 -- 2023)

Chair: Tinko Tinchev

14:00 -- 14:30 How to make AI with a good character?

Dimiter Dobrev

14:30 -- 15:00 Geometric constructions without ruler and compass

Vladimir Sotirov

15:00 -- 15:30 Modal logic with bi-implication is exponentially more succinct on BT and S4 models

Petar Iliev

15:30 -- 16:00 New subrecursive degrees of representations of irrational numbers based on Weihrauch intersections and trace functions

Ivan Georgiev

16:00 -- 16:30 Coffee break

Chair: Ivan Georgiev

16:30 -- 17:00 Measurable contact algebras

Philippe Balbiani, Quentin Gougeon, Tinko Tinchev

17:00 -- 17:30 Monadic second-order theories of postlinear orders and preorders

Grigor Kolev, Tinko Tinchev

17:30 -- 18:20 Invited talk: Real numbers and their representations

Lars Kristiansen

Hall B

Section: Challenges of the Digital World - Traditions and Innovative Solutions in Research and Education

Chair: Nikolina Nikolova

09:00 -- 09:30 Game as a learning, learning as a game

Trayan Iliev

09:30 -- 10:00 Need of problem solving courses

Ivan Tonov

10:00 -- 10:30 Innovation and the Cultural-Historical context in Mathematics education

Tanya Tonova

10:30 -- 11:00 Innovative practical pedagogical tools for CS and IT education

Yavor Papazov, Stanimira Jelezova

11:00 -- 11:30 Coffee break

11:30 -- 12:00 Cyber security concepts in the software development process

Mariya Harseva, Milen Petrov

12:00 -- 12:30 Innovative solutions in mental and educational health: Development of a mobile application for tracking daily activities

Viktoriya Pepieva, Milen Petrov

12:30 -- 13:00 Corporate E-learning based on organizational development vision

Lilyana Russeva

13:00 -- 14:00 Lunch

Section: Variational Analysis and Applications

Chair: Marian Fabian

14:00 -- 14:30 Fedorchuk compacta and LUR renormability

Todor Manev

14:30 -- 15:00 Metric embeddings of Laakso graphs into Banach spaces

Stephen J. Dilworth, Denka Kutzarova, Svetozar Stankov

15:00 -- 15:30 Lipschitz continuity of the regular graphical derivative

Stoyan Apostolov

15:30 -- 16:00 Continuity of the solutions of parametric optimization problems

Stoyan Apostolov, Dimitar Georgiev

20:00 Official dinner

Friday, September 27

Departure day

Up to 11:30 Check out