Using global characteristics of a centrifuge outflow experiment to determine unsaturated soil parameters

Several centrifugation scenarios enabling the determination of soil parameters for saturated-unsaturated flow in porous media are presented, investigated, and discussed. Only global characteristics of the infiltration process in a sample are used, so that only simple, noninvasive measurements are performed. The characteristics can be transient measurements of the rotational momentum, or of the gravitational center, or of the water amount injected and expelled from the sample. No information about the saturation or the head distribution in the sample is required. This setup is different from the common multioutflow experiments. We give numerical proof that this method allows for fast determination of soil parameters in comparison to traditional measurements based on equilibrium conditions. The mathematical model of infiltration is represented by Richards' strongly nonlinear and degenerate equation expressed in terms of soil parameters in the van Genuchten-Mualem ansatz. The parameter identification process is realized in an iterative way applying the Levenberg-Marquardt method. Numerical experiments support the efficiency of the analyzed method and allow one to identify the optimal centrifugation scenario for imbibition and drainage to be applied when using global characteristics

Numerical model for the determination of the soil retention curve from global characteristics obtained via a centrifuge

A novel centrifuge set-up for the study of unsaturated flow characteri\-stics in porous media is examined. In this set-up, simple boundary conditions can be used, but a free moving boundary between unsaturated-saturated flow arises. A precise and numerically efficient approximation is presented for the mathematical model based on Richards' nonlinear and degenerate equation expressed in terms of effective saturation using the Van Genuchten-Mualem approach for the soil parameters in the unsaturated zone. Sensitivity of the measurable quantities (rotational moment, center of gravity and time period to achieve quasi steady state) on the soil parameters is investigated in several numerical experiments. They show that the set-up is suitable for the determination of the soil parameters via the solution of an inverse problem in an iterative way

Game 128kB Using OpenGL

Bakalářská práce se zabývá tvorbou hry s omezenou velikostí . Práce popisuje metody pro omezení velikosti výsledné aplikace . Hlavní část práce popisuje metody pro generování grafického obsahu , pohybu po něm a reakce s ním . Zabývá se tvorbou textur a terénu .Bachelor thesis deal with creation of the game with limited memory space. It describes methods for reducing the size of the final application. Main part of the thesis describes methods for generating graphic content, as well as movement and interactions within it. It also deals with making of textures and terrain.

Convergence of Rothe's method in Hölder spaces

summary:The convergence of Rothe’s method in Hölder spaces is discussed. The obtained results are based on uniform boundedness of Rothe’s approximate solutions in Hölder spaces recently achieved by the first author. The convergence and its rate are derived inside a parabolic cylinder assuming an additional compatibility conditions

APPROACHES TO THE GAS CONTROL IN UCG

Underground Coal Gasification represents an alternative for conventional coal mining. This technology is also less expensive than traditional mining. It is expected that coal will be an important energy source in the coming decades. In requirement to improve the gasification process we must ensure that the combustion reactions generated enough energy to heat the reactants. This can be achieved by controlling the flow of oxidizing agents and the underpressure control at the exit of the reactor UCG. This paper aims to propose the stabilization of air flow as a main gasification agent injected to the gasifier, underground temperature and concentration of O2 in syngas. Also there is proposed the mechanism that could cope with uncertainties in the process of UCG and its control on stabilization level. Paper presents utilization of discrete controller with adaptation in order to stabilization of UCG process variables. The controllers were verified on experimental ex-situ reactor (generator)

Social work at the context of the comprehensive rehabilitation of people with disabilities

V této práci se zabývám rolí sociální práce v procesu koordinované rehabilitace osob se zdravotním, zjm. tělesným postižením, který nahlížím dvojím úhlem. Jednak jako plošnou snahu propojit jednotlivé rehabilitační segmenty (léčebný, pracovní, sociální a pedagogický) v jeden zákonem zaštítěný celistvý, prostupný celek dostupných služeb směřující k dosažení co nejvyššího funkčního potenciálu jedince a co nejvyšší míry jeho zapojení do života. Jednak jako se stejným cílem lokálně vznikající síť služeb rehabilitačního charakteru ve smyslu welfare mix. Ve výzkumné části se budu věnovat pozici sociálního pracovníka v instituci Jedličkova ústavu a školy, resp. v organizacích Centra služeb Vyšehrad.AJ In my theses I look into the problematic of comprehensive rehabilitation of people with health handicap from the perspective of social work by two different ways. Once as a trial to connect all the rehabilitation segments into one comprehensive by the law shielded unity with a goal to achieve the highest possible function potential of individual and the widest possible integration of person, once as a local welfare mix site of services with rehabilitation character with the same goal as in the first case. At the researche part I will focuse on a role of social workers in the institution of Jedličkův ústav a školy and Centrum služeb Vyšehrad, considered as institution providing services of comprehensive rehabilitation.HTF - Katedra psychosociálních věd a etikyHusitská teologická fakultaHussite Theological Facult

Convergence of a method for solving the magnetostatic field in nonlinear media

summary:For solving the boundary-value problem for potential of a stationary magnetic field in two dimensions in ferromagnetics it is possible to use a linearization based on the succesive approximations. In this paper the convergence of this method is proved under some conditions

A COMPARATIVE STUDY OF DATA-DRIVEN MODELING METHODS FOR SOFT-SENSING IN UNDERGROUND COAL GASIFICATION

Underground coal gasification (UCG) is a technological process, which converts solid coal into a gas in the underground, using injected gasification agents. In the UCG process, a lot of process variables can be measurable with common measuring devices, but there are variables that cannot be measured so easily, e.g., the temperature deep underground. It is also necessary to know the future impact of different control variables on the syngas calorific value in order to support a predictive control. This paper examines the possibility of utilizing Neural Networks, Multivariate Adaptive Regression Splines and Support Vector Regression in order to estimate the UCG process data, i.e., syngas calorific value and underground temperature. It was found that, during the training with the UCG data, the SVR and Gaussian kernel achieved the best results, but, during the prediction, the best result was obtained by the piecewise-cubic type of the MARS model. The analysis was performed on data obtained during an experimental UCG with an ex-situ reactor