Different HVDC grid types and the respective protection options are discussed. An earthed bi-pole HVDC grid was modeled in PSCAD, and using simulation results, the necessity of di/dt limiting inductors to contain the rise of fault currents within the capacity of current hybrid DC breakers is demonstrated. The impact of different inductor sizes on current rise was studied. A fault detection and localization scheme using the rate of change of voltage (ROCOV) measured at the line side of the di/dt limiting inductors is proposed. The protection system was modeled and tested under different fault types and locations. The results show that the proposed method of HVDC grid protection is feasible using the current hybrid DC breaker technology. A systematic procedure for setting the necessary protection threshold values is also demonstrated.

Thesis (Ph. D.)--University of Chicago, The Divinity School, August 2000. / Includes bibliographical references. Also available on the Internet.

The thesis analyzes the temperature field in construction details in an envelope of a wooden house. The fundamental task is a comparison of steady and unsteady calculation taking into account or disregarding the material properties depending on temperature. The partial task was to design a construction of envelope for wooden building and on the basis of this construction to create 2-D geometric models in the software Comsol Multiphysics which is based on the finite element method. For the calculation of the temperature field is applied boundary condition of the third order with actual values of the exterior temperature in winter. To maximize the credibility of simulation software are included the equation expressing the dependence on the temperature of material constants of timber and mineral wool. As the final result to the temperature field numerical models of the peripheral wall between stationary and non-stationary plot is analyzed mutual description of the behavior of thermal processes. In the results are further clarified the cause of the construction physical phenomena.

This diploma thesis deals with selection, construction and realization of measuring device of magnetostatic field and description of the basic laws used in magnetism. It also describes principles and functions of particular sensors and probes curently used for measuring of magnetic fields, especially fluxgate magnetometer, which has been constructed. The result of this work is a particular realisation of measuring device with functional testing measurements.

Presented dissertation discusses the influence of electromagnetic fields on the weight of the particles, which are considered in this work as substances with the hub. Theoretical knowledge was practically tested on plant organisms (early somatic embryos, fungal pathogens), theoretically the influence of electromagnetic field on cell structure was modeled. It was subsequently confirmed by a practical experiment assumption about the influence of electromagnetic fields on the weight of the particles. These experiments were preceded by a theoretical study of the problem and the formulation of a solution using Maxwell's equations, from which other descriptive equations and formulas were derived. The results of the experiments were presented at several professional conferences and published in professional journals and proceedings.

Aim. The take-off is regarded as the most important phase of the pole vault yet there is an insufficient amount of research on the ground reaction forces of the pole vault takeoff. At this time there is not any scientific research comparing force and time between takeoffs that are out, on and under. The purpose of this study is to compare the differences in ground reaction forces between pole vault take-offs that are out, on or under. Methods. Over five days, 15 male and female college pole vaulters completed 226 vaults on a (AMTI Accupower) force plate. The jumps were put into categories of out, on and under and analyzed by Accupower, and Dartfish software. Separate mixed modal ANOVAs (SAS 9.3) were applied (P≤.05) for comparison between jump types. Conclusions. There is no significant difference between ground reaction forces of the three jump types.

The thesis is focused on the design of a wideband detector used for detection of HIRF field. The detector, which is based on PICA antenna, was deeply examined and its´shape was also modificated for the purpose of achieving better omnidirectional and impedance characteristics. The thesis also deals with the design of cross PICA antenna variations, which purpose is to improve pattern bandwith. The PICA antenna variations mentioned were compared with one another at the end of the work. The end of the thesis also deals with the comparison of measured results gained from the specimen made with the results gained from the simulations.

Diploma thesis deal with measuring air-jet generated by low-velocity outlet. Diploma thesis piles of several part. First part includes velocity measurment (flow volumes) single ventilators. Follows measuring velocity distribution in air-jet generated by low-velocity outlet, his vizualization by the smoke method. Last point is problems errors and uncertainties measuring. Thesis likewise includes appendices, where there are mentioned tables from single maesuring and setting frequency transducers.

This thesis is focused influence of external electromagnetic fields to function of speed sensors. In this work is created summary of individual principles speed sensors and possible sources electromagnetic fields.

This diploma thesis examines current phenomenon of pole dance/sport. This activity which was originally performed in strip clubs was relatively recently redefined as a fitness activity offered at pole dancing studios initially for women, but now also for men. Despite the efforts to redefined pole dance as a fitness activity in the eyes of the public pole dance is still associated with its erotic roots and (therefore) with women. According to previous research pole dance is seen as a feminine and feminized activity. Men's participation in these activities is, according to studies, associated with the belief that those men are effeminate or homosexual and therefore construct their gender identity in ways which are inconsistent with the social ideas of masculinity. In this thesis I explore the ways in which male pole dancers construct their masculinity within this unique environment. I also explore what participation in the world of pole dance mean to men who take pole dancing classes and/or who teach them as well as the stereotypes placed upon men to act in a certain way to be considered masculine. In this research I also discuss the role of the body on construction of masculinity. Data were collected via semi-structured interviews with six Czech male pole dancers over the age of 18 and examined...