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On jet like bundles of vector bundles
(Mathematical Society of Serbia, 20211101)We describe completely the so called jet like functors of a vector bundle E over an mdimensional manifold M, i.e. bundles FE over M canonically depending on E such that F(E1 x(M) E2) = FE1 x(M) FE2 for any vector bundles ... 
Maxwell Points of Dynamical Control Systems Based on Vertical Rolling DiscNumerical Solutions
(MDPI, 20210712)We study two nilpotent affine control systems derived from the dynamic and control of a vertical rolling disc that is a simplification of a differential drive wheeled mobile robot. For both systems, their controllable Lie ... 
Connections in control strategy
(Estonian Academy of Sciences, 20140314)We present an infinitesimal interpretation of the control theory, particularly of the part concerning dynamic systems. We use the original concept of a bundle connection, which lies in the idea of fibre transportation along ... 
MultiScale Gaussian Normalization for Solar Image Processing
(Springer, 20140801)Extreme ultraviolet images of the corona contain information over a wide range of spatial scales, and different structures such as active regions, quiet Sun, and filament channels contain information at very different ... 
Existence and exact multiplicity of positive periodic solutions to forced nonautonomous Duffing type differential equations
(Bolyai Institute, University of Szeged, 20210908)The paper studies the existence, exact multiplicity, and a structure of the set of positive solutions to the periodic problem u''=p(t)u+q(t,u)u+f (t); u(0)=u(\omega), u'(0)=u'(\omega), where p, f\in L([0,\omega]) and q : ... 
Discrete Riccati matrix equation and the order preserving property
(Elsevier, 20210203)It is known that if a symmetric matrix differential equation has the order preserving property and the matrix dimension is at least 2, then this equation is the Riccati matrix differential equation (see A.N. Stokes, A ... 
Cuberootsubgroups of SL_2 over imaginary quadratic integers
(Vladimir Andrunakievich Institute of Mathematics and Computer Science, 20210901)All cube roots of the identity in the special linear group of $2\times 2$matrices with entries in the ring of integers in $\mathbb Q[\sqrt{d}]$ are described. These matrices generate subgroups of the third order; it is ... 
Identifying the Coronal Source Regions of Solar Wind Streams from Total Solar Eclipse Observations and in situ Measurements Extending over a Solar Cycle
(IOP PUBLISHING LTD, 20210412)This letter capitalizes on a unique set of total solar eclipse observations acquired between 2006 and 2020 in white light, Fe xi 789.2 nm (Tfexi = 1.2 0.1 MK), and Fe xiv 530.3 nm (Tfexiv = 1.8 0.1 MK) emission complemented ... 
On Münchhausen numbers
(Bulgarian Academy of Sciences, 20210316)The remarkable property of the number 3435, namely 3435 = 3^3 + 4^4 + 3^3 + 5^5, was formalized to the notion of Münchhausen numbers. Properties of these numbers are studied and it is showed that although there are only ... 
Decaying positive global solutions of second order difference equations with mean curvature operator
(University of Szeged, 20201221)A boundary value problem on an unbounded domain, associated to difference equations with the Euclidean mean curvature operator is considered. The existence of solutions which are positive on the whole domain and decaying ... 
Solvability of a nonlocal boundary value problem for linear functional differential equations
(Springer, 20130814)In the paper, the problem on the existence and uniqueness of a solution to the nonlocal problem u'(t)=l(u)(t)+q(t), u(a)=h(u)+c is studied. They are found conditions guaranteeing the unique solvability of considered problem. 
A Simple Drug Delivery System for PlateletDerived Bioactive Molecules, to Improve Melanocyte Stimulation in Vitiligo Treatment
(MDPI, 20200910)Vitiligo is the most common depigmentation disorder of the skin. Currently, its therapy focuses on the halting of the immune response and stimulation of the regenerative processes, leading to the restoration of normal ... 
WEDM used for machining high entropy alloys
(MDPI, 20201025)Unconventional wire electrical discharge machining technology (WEDM) is a key machining process, especially for machining newly emerging materials, as there are almost no restrictions (only at least minimal electrical ... 
A Spectral Emissivity Library of Spoil Substrates
(MDPI, 20160910)Postmining sites have a significant impact on surrounding ecosystems. Afforestation can restore these ecosystems, but its success and speed depends on the properties of the excavated spoil substrates. Thermal infrared ... 
Sharp Feature Detection as a Useful Tool in Smart Manufacturing
(MDPI, 20200630)Industry 4.0 comprises of wide spectrum of developmental processes within the management of manufacturing and chain production. This intension leads to the increased need for highquality methods for digitization and object ... 
A mixed integer linear programming model applied in barge planning for Omya
(Elsevier, 20151201)The article presents a mathematical model for barge transport planning, which is part of a decision support system recently taken into use by the Swiss company Omy. The bargeplanning problem falls in the category of ... 
Straddled numbers: numbers equal to the sum of powers of consecutive primes from the least prime factor to the largest prime factor
(Bulgarian Academy of Sciences, 20190702)Positive integers equal to the sum of powers of consecutive primes from the least prime factor to the largest prime factor are studied. They are called the straddled numbers and their properties are derived. There are also ... 
Dual Numbers Approach in Multiaxis Machines Error Modeling
(Hindawi, 20140601)Multiaxis machines error modeling is set in the context of modern differential geometry and linear algebra. We apply special classes of matrices over dual numbers and propose a generalization of such concept by means of ... 
Precision Machining of Nimonic C 263 Super AlloyUsing WEDM
(MDPI, 20200624)Wire electrical discharge machining (WEDM) is an unconventional and very efficient technology for precision machining of the Nimonic C 263 super alloy, which is very widespread, especially in the energy, aerospace and ... 
Analysis of Machinability and Crack Occurrence of Steels 1.2363 and 1.2343ESR Machined by DieSinking EDM
(MDPI, 20200419)Diesinking electric discharge machining (EDM) is an indispensable technological operation, especially in the production of molds and all internal and external shapes and cavities. For this reason, the effect of machine ...