Search results for: P. Mazal

Authors: Krisstalova Dana, Mazal Jan

Abstract:

This article deals with geographical conditions in terrain and their effect on the movement of vehicles, their effect on speed and safety of movement of people and vehicles. Finding of the optimal routes outside the communication is studied in the army environment, but it occur in civilian as well, primarily in crisis situation, or by the provision of assistance when natural disasters such as floods, fires, storms etc., have happened. These movements require the optimization of routes when effects of geographical factors should be included. The most important factor is the surface of a terrain. It is based on several geographical factors as are slopes, soil conditions, micro-relief, a type of surface and meteorological conditions. Their mutual impact has been given by coefficient of deceleration. This coefficient can be used for the commander`s decision. New approaches and methods of terrain testing, mathematical computing, mathematical statistics or cartometric investigation are necessary parts of this evaluation.

Keywords: movement in a terrain, geographical factors, surface of a field, mathematical evaluation, optimization and searching paths

Procedia PDF Downloads 393

Authors: Hannah Riva, Sarah Mazal, Jessica L. Marquez, Michael Rains

Abstract:

A 70-year-old female with a Fitzpatrick skin phenotype II presented with a 13-year history of a scaly rash located on the left breast and bilateral pretibial regions. The patient’s past medical history was otherwise unremarkable, with the exception of surgery involving the left breast. Physical examination revealed infiltrative hyperpigmented scaly plaques and nodules located on the left breast and pretibial regions bilaterally. A negative systemic workup excluded organ involvement. A clinical diagnosis of cutaneous sarcoidosis was made. Prior treatments included triamcinolone 0.1% topical cream and clobetasol 0.05% ointment, which failed to show improvement. Full-body narrow-band UVB (NBUVB) treatment was performed on a tri-weekly basis for eight months. NBUVB dosage was slowly titrated from 300 mJ/cm2 to a final dose of 1800 mJ/cm2 to prevent discomfort and burning sensations. Throughout the duration of her treatment, the patient adhered to a regimen of clobetasol 0.05% topical ointment applied twice daily in two-week intervals. Improvement was noticed after two months, with continued improvement up to eight months. The patient is continuing NBUVB phototherapy treatments for maintenance. In our case, NBUVB phototherapy treatment demonstrated promising results with improvement after two months of treatment. Physicians should consider NBUVB phototherapy as an effective option for patients presenting with cutaneous sarcoidosis.

Keywords: dermatology, sarcoidosis, phototherapy, ultraviolet

Procedia PDF Downloads 38

Authors: V. Mentl, V. Koula, P. Mazal, J. Volák

Abstract:

Nowadays, the acoustic emission is a widely recognized method of material damage investigation, mainly in cases of cracks initiation and growth observation and evaluation. This is highly important in structures, e.g. pressure vessels, large steam turbine rotors etc., applied both in classic and nuclear power plants. Nevertheless, the acoustic emission signals must be correlated with the real crack progress to be able to evaluate the cracks and their growth by this non-destructive technique alone in real situations and to reach reliable results when the assessment of the structures' safety and reliability is performed and also when the remaining lifetime should be evaluated. The main aim of this study was to propose a methodology for evaluation of the early manifestations of the fatigue cracks and their growth and thus to quantify the material damage by acoustic emission parameters. Specimens made of several steels used in the power producing industry were subjected to fatigue loading in the low- and high-cycle regimes. This study presents results of the crack growth rate measurement obtained by the classic compliance change method and the acoustic emission signal analysis. The experiments were realized in cooperation between laboratories of Brno University of Technology and West Bohemia University in Pilsen within the solution of the project of the Czech Ministry of Industry and Commerce: "A diagnostic complex for the detection of pressure media and material defects in pressure components of nuclear and classic power plants" and the project “New Technologies for Mechanical Engineering”.

Keywords: fatigue, crack growth rate, acoustic emission, material damage

Procedia PDF Downloads 333