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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 ... 
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 ... 
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 ... 
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 ... 
Simulation of the acoustic wave propagation using a meshless method
(EDP Sciences, 20170512)This paper presents numerical simulations of the acoustic wave propagation phenomenon modelled via Linearized Euler equations. A meshless method based on collocation of the strong form of the equation system is adopted. ... 
On a product of universal hyperalgebras
(Faculty of Mathematics and Computer Science, Ovidius University, 20150515)We introduce and study a new operation of product of universal hyperalgebras which lies, with respect to set inclusion, between the cartesian product of the hyperalgebras and the cartesian product of their idempotent hulls. ... 
On the stability of some properties of partial algebras under powers
(SAV, 20140401)In the paper, we study eight properties of partial algebras most of which are related to diagonality. For each of the properties, we give sufficient conditions under which this property is preserved by powers of partial algebras. 
Local controllability of trident snake robot based on subRiemannian extremals
(Universit`a del Salento, 20170524)To solve trident snake robot local controllability by differential geometry tools, we construct a privileged system of coordinates with respect to the distribution given by Pffaf system based on local nonholonomic conditions ... 
Threeaxes error modeling based on second order dual numbers
(SpringerVerlag, 20151117)The aim of the paper is to employ the dual numbers in the multi axes machine error modelling in order to apply the algebraic methods in computations. The calculus of higher order dual numbers allows us to calculate with ... 
Applications of the discontinuous Galerkin method to propagating acoustic wave problems
(SAGE Publishing, 20170616)The purpose of this article is to demonstrate that the discontinuous Galerkin method is efficient and suitable to solve linearized Euler equations, modelling sound propagation phenomena. 
Reconstruction of an ellipse from its raster image
(Academic Publications, Ltd, 20150414)Motivated by practical application, we investigate the ways how to obtain a description of an ellipse whose circumscribed rectangle is known exactly and whose coordinates of touching points are known up to a certain ... 
Pool & Discard Algorithm for Chance Constrained Optimization Problems
(IEEE, 20200427)In this paper, we describe an effective algorithm for handling chance constrained optimization problems, called the Pool & Discard algorithm. The algorithm utilizes the scenario approximation framework for chance constrained ...