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The Use of Biomechanics as Supporting Argumentation for Expert Opinion Conclusions
Veselý, Vratislav ; Ravnik, David (advisor) ; Maršík, František (referee) ; Horák, Zdeněk (referee)
of the dissertaton Title: The use of biomechanics as a supportng argumentaton for the conclusions of expert opinions Auhtor: Ing. Vratslav Veselý, MBA Keywords: trafc accident, mechanism of injury, head injury, pedestrian, car windscreen, head impact velocity, deformaton zones The aim of this dissertaton is to map the mechanical propertes of the bones of the face and skull from the available literature and to describe the mechanisms of brain and cervical spine injuries. The descripton of these mechanisms contributes to the elucidaton of the origin of injuries from a purely mechanical/biomechanical perspectve, and in forensic practce contributes to the understanding of the situaton by other engineering professions not involved in forensic medicine. The strength and stfness parameters of the bones of the face and skull are used to determine the magnitude, directon and locaton of possible forces for fracture formaton, etc. Another objectve is to propose and describe a simple analytcal approach for determining the velocity of the head when striking the windshield of an automobile. To address the dependence of head impact velocity and car speed, and the efect of windscreen tlt. Using experimental testng, to describe the defects produced on the windscreen of a car afer a crash of...
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Information Extraction from structured business documents by learning from similarity
Holeček, Martin ; Maršík, František (advisor) ; Liwicki, Marcus (referee) ; Mesiti, Marco (referee)
The automation of document processing is gaining recent attention due to the great potential to reduce manual work through improved methods and hardware. In this area, neural networks have been applied before - even though they have been trained only on relatively small datasets with hundreds of documents so far. To successfully explore deep learning techniques and improve the information ex- traction results, a dataset with more than twenty-five thousand documents (pro forma invoices, invoices and debit note documents) has been compiled, anonymized and is published as a complement of this work. In the first part of the research, we will examine the documents from the point of view of table detection, present a survey on table detection methods and ultimately rephrase the table detection as a text box labelling problem to optimize micro F1 score of per-word classification. We will show that we can extract specific information from structurally different tables or table-like structures with one trainable model that features a comprehen- sive representation of a page using graph over word-boxes, positional embeddings and trainable textual features. The first part is concluded with a novel neural network model that beats multiple baselines and achieves strong, practical results on the presented dataset....
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The connection between the principle of the least action and the thermodynamic condition of stability
Maršík, František ; Trávníček, Zdeněk ; Antošová, Zuzana
The extended principle is formulated for a material point (M.P.) X, which has nonzero mass, temperature, and trajectory x(X,t). The Lagrangian of this variation principle is equal to the kinetic energy from which, the internal energy of the material point (which depends on the entropy) and the additional energy caused by the frictional force are subtracted. The relation between the inertial force and the entropy gradient is found and the gravitational force is completely replaced by the entropy gradient. Thanks to the mentioned properties of the total enthalpy, the Thermodynamic criterion of stability of the state of M.P., is formulated.
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Analysis of spontaneous collapse in elastic tubes
Netušil, Marek ; Maršík, František (advisor) ; Horný, Lukáš (referee)
Interaction of fluid with elastic tube is complicated issue studied by many scientific departments around the world. Object of this thesis is to analyze simplified one-dimensional model. At the beginning, used balance equations and basics of hyper-elasticity are presented. Then we review three most common materials used for the description of blood vessels and other soft tissues. For these materials we introduce a method which we use to derive a relation between tube deformation and transmural pressure (i.e. difference between inner and outer pressure). In mathematical section we give brief review of theory of nonlinear hyperbolic equations and some relatively new results in the field of existence and uniqueness of a solution of one-dimensional hyperbolic system. The "building stone" of these results is a solution of the so-called Riemann problem. We use a method for finding exact solutions to the Riemann problem to analyze studied model of fluid-tube interaction and study dependence of the qualitative behavior of the solution on the material properties of the tube wall.
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Suggestion of an optimal numerical method for solution of the Rayleigh-Plesset equation with rebounding
Petrík, Peter ; Maršík, František (advisor) ; Zima, Patrik (referee)
Na/ev pram: X a v i l i opt.inia.lm niunericke metody pro le.^ loviuce s pmdkyini kavil acni'mi kolapsx Autor: Peter Peln'k Katedra (usl.av): Malemalickv uslav I ' K Vedouci bakalafske prace: Piol. hit!,. Marsik Fianlisek. UrSc. e-mail vodouci'lio: marsik'nt .ras.c/ Abstrnkt: V praci si ndnicme presnost a casovou miioenosl jednokrokovvch ex- plicit niVh I l i r t u d ( Klin;!,c-l\UtT;i. Bulirscll-St oer) s ;id;ipt a h i l l l l l l l klokem v Kayleijdl- Plesselove lovnici, ktera popiMije vyvoj polomei n pi v nne l)iil)iiii\ \ kapalinr sc /nicnaini tln.ku. McUidv pndcriiujf lok/ilni chybii \ nn.stccli kdlapsu hiihlin. av^ik ^lobi'ilnf c!i\'l)a /usta"\;i \ nidu pou/itc tulcrancc, Bulii'scli-St.ocr inctdda \a ncjiiKMis] CMSOVOH nai'ociK)St. V pfi'padr [^ini^c-Kullii iiK'tnd /;i.\isi \ylicr o|itiiiuil)ii nirtdd\ na pou/itr lolcranci. Pli slrcdnicli tnln ancich ur\'i lilujc \-vpocc! i pnuxiti iT^ukiri/acr. (j. xavcdciii niA'f'1 jicx/ixihlr pmiiirnnr nii'slo rasu. ('MSOV-'I ii/irocno^l poti/,it(' i)nMod\c tiicni' s ruxnynii pou/Jtyini vaiiatil a.nii rovtiicc (i/u(cnuick;i aproxi- inacr/adialiat ick/i aproxiniacc plvniic sln/ky olisa.hu luililiiiy. si lacilt'lun./ nest a.rit.clna kapalina)- I'l'i nekteryeh naslavcniYli \st ilpni'eli paranirl I'll \ i/,ol enilirkc vai'iatile io\"iiice doelii'txi k padu \'ypoelu...
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Metoda vrstevnic a modelování proudění nemísitelných nestlačitelných tekutin
Čapek, Marek ; Hron, Jaroslav (advisor) ; Maršík, František (referee)
The focus of this thesis are three-dimensional simulations of flow of two immiscible incompressible viscous fluids and distribution of concentration transported by the flow where the free interface between the fluids is realized by level-set method. It is applied to blood flow and coagulation. The blood flow is described using Navier-Stokes equations for incompressible fluids, numerical method is done by finite element method with Q2 - Q1 elements and the problem is solved as coupled. The distribution of concentration is described using transport equation, discretization is done using Q1 elements.
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Matematická analýza a výpočtový algoritmus Rayleighovy-Plessetovy rovnice v okolí prudkého kolapsu bublinky.
Petrík, Peter ; Maršík, František (advisor) ; Rudolf, Pavel (referee)
The Rayleigh-Plesset equation is commonly used to describe the dynamics of spherical bubbles in water. However, as high-speed observations show, the bubble looses its spherical shape during the violent collapse and often ssions into a number of smaller bubbles before it rebounds again or dissolves completely. The objective of the work is to bridge the gap between the \spherical\ Rayleigh-Plesset approach and the \non-spherical\ behavior of the collapsing bubble in conditions when the Rayleigh-Plesset equation is no longer valid. The objective is achieved in 3 steps. First, the new criterion for the assessment of the reliability of the Rayleigh-Plesset equation is proposed. Second, the analysis of the shape stability of the spherical surface of the bubble during the collapse lead to the development of a physical model, which incorporates the loss of shape stability, surface energy dissipation and the ssion process. Moreover it estimates the number of bubble fragments as well as conditions when the ssion occurs. Finally, theoretical results are incorporated into the complex numerical code, with the focus on error estimation, specially propagation of rounding error. The sample numerical results for typical hydrodynamic cavitation situations were calculated. The results of this work have to be further con rmed...
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