Aspect-oriented Approach to Metamodel Abstraction

A software system maintenance represents an important part of software system's lifetime. The most common reasons to change a software system are bug fixes and adding of a new functionality. Software maintenance itself is a difficult and complex process. Before applying a change, it is important to understand the software system's source code as well as the application domain. This paper presents our innovative approach to improve software system comprehension in order to simplify its maintenance. Instead of analyzing all the program code, our approach focuses on parts which are built using predefined well known software libraries. The knowledge of both -- the libraries and the way they are used in software systems -- allows us to identify certain concepts of the software system. This information is used to create metamodels of these concepts. The metamodel is created at a higher level of abstraction than the level of concept implementation

Combined Approach to Program and Language Evolution

Program can be viewed as a sequence of statements that are aimed to produce some result. The execution is done by a platform that interprets the program sequence of statements. The new result of a computation can be achieved by modification of a program, a language interpreter, or both. Software evolution as long-term process can be supported by adaptive language and by environment, which offers reflective possibilities. This paper presents our adaptive approach to both program and language modification in order to support dynamic evolution. Effective software evolution needs to be supported by appropriate execution environment. We have proposed such experimental execution environment, which allows both run-time program and language modification. As we hope, mutating a programming language to a higher abstraction may decrease structural complexity of programs in the future

High-resolution numerical modelling of altimetry-derived gravity data

VEGA 1/0486/2

Influence of domain walls thickness, density and alignment on Barkhausen noise emission in low alloyed steels

This study deals with the characterization of low alloyed steels of diferent yield strengths (varying in the range of 235–1100 MPa) via Barkhausen noise emission. The study investigates the potential of this technique to distinguish among the low alloyed steels and all signifcant aspects contributing to Barkhausen noise, such as the residual stress state, microstructure expressed in terms of dislocation density, grain size, prevailing phase, as well as associated aspects of the domain wall substructure (domain wall thickness, energy, their spacing and density in the matrix). Barkhausen noise in the rolling as well as transversal direction grows along with the yield strength (up to 500 MPa) and the corresponding grain refnement of ferrite. As soon as the martensite transformation occurs in a high strength matrix, this evolution saturates, and remarkable magnetic anisotropy is developed when Barkhausen noise in the transversal direction grows at the expense of the rolling direction. The contribution of residual stresses as well as the domain wall thickness is only minor, and the evolution of Barkhausen noise is driven by the density of the domain walls and their realignment.Web of Science131art. no. 568

Atom transfer radical polymerization of pyrrole-bearing methacrylate for production of carbonyl iron particles with conducting shell for enhanced electromagnetic hielding

The conducting polymer poly(2-(1H-pyrrole-1-yl)ethyl methacrylate (PPEMA) was synthesized by conventional atom transfer radical polymerization for the first time from free as well as surface-bonded alkyl bromide initiator. When grafted from the surface of carbonyl iron (CI) a substantial conducting shell on the magnetic core was obtained. Synthesis of the monomer as well as its polymer was confirmed using proton spectrum nuclear magnetic resonance (H-1 NMR). Polymers with various molar masses and low dispersity showed the variability of this approach, providing a system with a tailorable structure and brush-like morphology. Successful grafting from the CI surface was elucidate by transmission electron microscopy and Fourier-transform infrared spectroscopy. Very importantly, thanks to the targeted nanometer-scale shell thickness of the PPEMA coating, the magnetization properties of the particles were negligibly affected, as confirmed using vibration sample magnetometry. Smart elastomers (SE) consisting of bare CI or CI grafted with PPEMA chains (CI-PPEMA) and silicone elastomer were prepared and dynamic mechanical properties as well as interference shielding ones were investigated. It was found that short polymer chains grafted to the CI particles exhibited the plasticizing effect, which might be interesting from the magnetorheological point of view, and more interestingly, in comparison to the neat CI-based sample, it provided enhanced electromagnetic shielding of nearly 30 dB in thickness of 500 mu m. Thus, SE containing the newly synthesized CI-PPEMA hybrid particles also exhibited considerably enhanced damping factor and proper mechanical performance, which make the material highly promising from various practical application points of view.Ministry of Education, Youth and Sports of the Czech Republic-DKRVO [RP/CPS/2022/003]; Internal Grant Agency of Tomas Bata University in Zlin [IGA/CPS/2021/003]; Integrated Infrastructure Operational Programme - ERDF [313021T081]; Slovak Research and Development Agency [APVV-19-0338]; Slovak Grant Agency VEGA [2/0129/19]; Qatar University Grant [QUCG-CAM-22/23-504]RP/CPS/2022/003; Slovenská Akadémia Vied, SAV: 313021T081; Tomas Bata University in Zlin, TBU: IGA/CPS/2021/003; Qatar University, QU: QUCG-CAM-22/23-504; Agentúra na Podporu Výskumu a Vývoja, APVV: APVV-19-0338; Vedecká Grantová Agentúra MŠVVaŠ SR a SAV, VEGA: 2/0129/19; European Regional Development Fund, ERD

Discontinuous wave equations and a topological degree for some classes of multi-valued mappings

summary:The Leray-Schauder degree is extended to certain multi-valued mappings on separable Hilbert spaces with applications to the existence of weak periodic solutions of discontinuous semilinear wave equations with fixed ends

Abstraction of Meaningful Symbolized Objects

We describe the notion of abstraction and conceptualization of information obtained by symbolization of letters. We are able to recognize already observed information with those abstracted concepts. Further more, we are also able to recognize similar meaningful objects. Similarities identification is based on a repetition in the structure of information symbolized as a regular language string. We discuss approaches of repetition identification, i.e., longest repeating non-overlapping subsequence and longest common subsequence. Then we apply those approaches to the symbolized letters, thus obtaining abstracted information in the form of concepts