Nonabelian dualization of plane wave backgrounds

We investigate plane-parallel wave metrics from the point of view of their (Poisson-Lie) T-dualizability. For that purpose we reconstruct the metrics as backgrounds of nonlinear sigma models on Lie groups. For construction of dual backgrounds we use Drinfel'd doubles obtained from the isometry groups of the metrics. We find dilaton fields that enable to satisfy the vanishing beta equations for the duals of the homogenous plane-parallel wave metric. Torsion potentials or B-fields, invariant w.r.t. the isometry group of Lobachevski plane waves are obtained by the Drinfel'd double construction. We show that a certain kind of plurality, different from the (atomic) Poisson-Lie T-plurality, may exist in case that metrics admit several isometry subgroups having the dimension of the Riemannian manifold. An example of that are two different backgrounds dual to the homogenous plane-parallel wave metric.Comment: 18 page

Classical solutions of sigma models in curved backgrounds by the Poisson-Lie T-plurality

Classical equations of motion for three-dimensional sigma-models in curved background are solved by a transformation that follows from the Poisson-Lie T-plurality and transform them into the equations in the flat background. Transformations of coordinates that make the metric constant are found and used for solving the flat model. The Poisson-Lie transformation is explicitly performed by solving the PDE's for auxiliary functions and finding the relevant transformation of coordinates in the Drinfel'd double. String conditions for the solutions are preserved by the Poisson-Lie transformations. Therefore we are able to specify the type of sigma-model solutions that solve also equations of motion of three dimensional relativistic strings in the curved backgrounds. Simple examples are given

Flat coordinates and dilaton fields for three--dimensional conformal sigma models

Riemannian coordinates for flat metrics corresponding to three--dimensional conformal Poisson--Lie T--dualizable sigma models are found by solving partial differential equations that follow from the transformations of the connection components. They are then used for finding general forms of the dilaton fields satisfying the vanishing beta equations of the sigma models.Comment: 16 pages, no figure

The educational computer program for assignment task analyses

Předkládaná diplomová práce se zabývá problematikou distribučních úloh, přesněji přiřazovacím problémem řešeným Maďarskou metodou a okružním dopravním problémem ("problém obchodního cestujícího"). Cílem této práce je praktické zpracování daných úloh v jazyce C++. Přiřazovací problém formou výukového programu, pomocí kterého by měl být uživatel schopen pochopit a naučit se dané problematice. Druhá část programu se zaměřuje na eliminaci parciálních smyček u okružního dopravního problému vznikajících při řešení obecnou Maďarskou metodou.ObhájenoThe present thesis deals with the distribution problems, more specificly assignment problem to be solved by Hungarian method and traveling salesman problem. The aim of this work is the practical solution of these tasks in C ++. Assignment problem through the educational program thanks to which the user should be able to understand and learn the issue. The second part of the program focuses on the elimination of partial loops in traveling salesman problem arising in dealing with the general Hungarian method

The conception of sport training for young judoists

Title: The Conception of Sports Training for Young Judoists Objectives: The main aim of this work is to describe and assess a suitable conception of training for young judoists. The paper also points out the effective methods of training and the aspects that need to be prioritized and avoided by the judo instructor. The focus is also on the control of training and the levels of general movement skills of the selected group. Methods: The author used various methods of data collection and the analysis of technical bibliografy which was focused on general sports preparations, study of available materials for judo training and own practice of the author. The materials and the bibliography were analyzed and structured according to applicability to the specific subjects. Results: The results of this paper emphasize the importance of development of various aspects while training young pupils. The results also stress the necessity of frequent training controls. Keywords: judo, training, young judoists, conception, batery of test

The conception of sport training for young judoists

Title: The Conception of Sports Training for Young Judoists Objectives: The main aim of this work is to describe and assess a suitable conception of training for young judoists. The paper also points out the effective methods of training and the aspects that need to be prioritized and avoided by the judo instructor. The focus is also on the control of training and the levels of general movement skills of the selected group. Methods: The author used various methods of data collection and the analysis of technical bibliografy which was focused on general sports preparations, study of available materials for judo training and own practice of the author. The materials and the bibliography were analyzed and structured according to applicability to the specific subjects. Results: The results of this paper emphasize the importance of development of various aspects while training young pupils. The results also stress the necessity of frequent training controls. Keywords: judo, training, young judoists, conception, batery of test

Rotating machines and their insulation systems

Bakalářská práce se věnuje izolačnímu systému točivých elektrických strojů. Práce pojednává o točivých elektrických strojích, jejich rozdělení, principy a konstrukcemi. Dále se věnuje vlastnostem izolačních materiálů (elektrická pevnost, rezistivita, relativní permitivita, dielektrické ztráty, ztrátový činitel tg?), popisuje výbojovou činnost vznikající u vedení strojů. Popisuje a porovnává hlavní výrobní technologie izolací točivých elektrických strojů Resin ? Rich a VPI a materiály použité pro jejich výrobu.Katedra technologií a měřeníObhájenoBachelor thesis deals with insulation system of electrical rotating machines. The work discusses the rotating electrical machines, their classification, principles and structures. Further, the work deals with the properties of insulating materials (dielectric strength, resistivity, relative permittivity, dielectric loss, disipation factor tg?). The thesis describes the partial discharge activity in the machines machines. The work compares the main production technology of rotating electrical machines insulation - Resin - Rich and VPI and also materials which are used for their production

Influence of body composition on explosive power of elite judokas

Title: Influence of body composition on explosive power of elite judokas Objectives: The main aim of the thesis is to discover whether the body composition effects the explosive power of elite judokas. The work also depicts the development of the explosive power during training and describes how to measure and compare the explosive power in upper limbs of a selected group of professional judo fighters within a general and specific exercise. Another aim of the thesis is to determine which weight categories are characterized by the biggest explosive power in upper limbs and whether this power mounts with the increasing weight category. Methods: The thesis has an empirical and theoreticalcharacter. Methods of data collecting, analysis of technical literature in the field of general sports preparation and judo training were used for the research. For the evaluation, the basic statistic methods and Spearman correlative coefficient were applied. Results: The results of the thesis point out the fact that the explosive power doesn't depend on the amount of active substance in the body of a contestant. The best results in the amount of explosive power from the testing exercises were achieved by the individuals within the weight category up to 90 kg, 81 kg and 100 kg. It has also been affirmed that the..