This thesis deals with the cutting of steel thin-walled parts by slitting saw. Its subject is to study and test of cutting edges of slitting saws with a goal to reduce cutting forces to a minimum. The thesis is divided into the theoretical and practical part. In the theoretical part, existing knowledge about slitting saws and general cutting technology is analyzed. In the practical part testing of four slitting saws with different geometries of cutting edges during machining of chosen thin-walled part is performed. The performed measurements show that by the proper choice of the geometry of cutting edge, the cutting force can be reduced approximately by 30 %.

The thesis deals with the transformation of the former sawmill located in the center of the village of Bílá in Beskydy. The proposal addresses the gradual integration of the complex into the ski resort development structure.

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El reformado catalítico de hidrocarburos con vapor de agua es una de las tecnologías más utilizadas para la obtención de hidrógeno, materia prima muy importante para la industria química, petroquímica y también como combustible limpio en las pilas electroquímicas. El uso de hidrocarburos líquidos se beneficia de la infraestructura ya creada para el almacenamiento y distribución de combustibles. Para este proceso se emplean catalizadores de tipo metal/soportado basados en níquel. Los esfuerzos actuales de investigación se centran en el desarrollo de nuevos catalizadores más activos y estables en un rango amplio de condiciones de operación, así como flexibles para reformar distintos hidrocarburos. En este trabajo doctoral se ha estudiado el comportamiento de óxidos mixtos de níquel, magnesio y aluminio, obtenidos mediante descomposición térmica de hidróxidos dobles laminares que ofrecen la oportunidad de controlar la naturaleza de los centros activos, de su entorno, así como la textura y estabilidad del catalizador, en la reacción de reformado de nafta con vapor de agua. Se ha estudiado el efecto de las condiciones de operación sobre la conversión de hidrocarburo y distribución de productos de reacción. Y también el efecto de algunas variables modificadas durante la síntesis del catalizador, así como la composición e introducción de promotores, sobre la actividad catalítica que muestran los materiales preparados. De los mejores catalizadores se ha estudiado su estabilidad y se ha realizado un estudio cinético y mecanístico del proceso. Por último se ha estudiado la actividad de estos materiales en el reformado de gas natural, diesel y aceite de girasol. / Morlanes Sanchez, N. (2007). Obtención de hidrógeno mediante reformado catalítico de nafta con vapor de agua [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/2185

There now exists an abundant collection of conjectures and results, of various complexities, regarding the diophantine properties of Shimura varieties. Two central such statements are the Andre-Oort and Zilber-Pink Conjectures, the first of which is known in many cases, while the second is known in very few cases indeed. The motivating result for much of this document is the modular case of the Andre-Oort Conjecture, which is a theorem of Pila. It is most commonly viewed as a statement about the simplest kind of Shimura varieties, namely modular curves. Here, we tend instead to view it as a statement about the properties of the classical modular j-function. It states, given a complex algebraic variety V, that V contains only finitely many maximal special subvarieties, where a special variety is one which arises from the arithmetic behaviour of the j-function in a certain natural way. The central question of this thesis is the following: what happens if in such statements we replace the j-function with some other kind of modular function; one which is less well-behaved in one way or another? Such modular functions are naturally called nonclassical modular functions. This question, as we shall see, can be studied using techniques of o-minimality and point-counting, but some interesting new features arise and must be dealt with. After laying out some of the classical theory, we go on to describe two particular types of nonclassical modular function: almost holomorphic modular functions and quasimodular functions (which arise naturally from the derivatives of the j-function). We go on to prove some results about the diophantine properties of these functions, including several natural Andre-Oort-type theorems, then conclude by discussing some bigger-picture questions (such as the potential for nonclassical variants of, say, Zilber-Pink) and some directions for future research in this area.

The thesis deals with the optimization of project activities in the software EPLAN Electric P8. First part introduces electrotechnical software EPLAN, the basic functions, and explains the methodology of the work in the program environment. This is followed by an analysis of the state of the electrical documentation of the TAC 75 circular saw manufactured by Exactcut s. r. o., and the method of designing. The thesis is also focused on the individual problems that make barriers between the average and the high quality level of design and the ability to use the available features of the purchased software. Thereafter, individual optimization steps and partial methods of reaching aims are described. Part of the thesis is devoted to finding solutions for interconnection of two engineering branches, which are electric and fluid technologies and in the end are revealed expansion modules of software, which can be used to achieve a higher level of professional planning activity.

This Master's thesis summarizes the current legislative requirements resulting from the Directives of the European Parliament and Council and the legislative requirements of the Czech Republic in the field of cutting machines, with a focus on band saws. Furthermore, there is also an analysis of the requirements of the relevant harmonized standards. For information sorting, check lists for the construction of a band saw and a process map of the construction of the saw have been made. In the last part of this work, the selected safety applications were completed for the band saw.

This work is focused on the design and construction of component parts of resistance saw. Mechanical parts consist of a movable bracket and a taut cutting wire of Constantan. Electrical parts are designed to supply and control temperature of the cutting wire. The current intensity in the cutting wire is compared with the required current intensity. The difference of these two measurements is fed into a PI - controller. The next part is a PWM generator which generates the square wave signal. The pulse ratio of this signal is proportional to the required temperature of the cutting wire. This signal switches a switching converter that consists of a power transistor P-MOSFET IRF5210 and a diode MBR20100CT. Choking coil with a ferrite E core and with the cutting wire is connected to the output of the converter.

The diploma thesis is focused on the use of technical innovation as a tool for increasing competitiveness of the wire saw for cutting silicon. In the paper are described theoretical bases for solving of product innovation. Based on market analysis, customer feedback and the results of functional analysis, in the diploma thesis are proposed innovations, which should contribute to increase competitiveness of the product on the global market.

The thesis deals with possibilities of using of mobile band saws. An economic analysis of band saw utilization for woodworking was carried out. Further the work evaluates and analyses the technological string of lumber production in a selected area. In the first part there is a study of current state of technological string of saw timber production. The second chapter deals with the evaluation of state in consideration of woodworking in relation to selected location of production facilities. The third part is focused on evaluation of possibilities of mobile band saw utilization that is carried out on Husqvarna SMB - 70. The fourth section describes technological variations and tries to determine criteria for choosing of the best variant. It details opportunities of a small - grower that tries to find the most suitable variant by selling a wood, so as it brings the maximum profit. The work deals with various possibilities of timber production in which the band saw is included. Technical parameters of particular saws are described here. And by means of economic parameters the most suitable technology for sawn wood production is determined. The goal of this thesis is to choose a suitable technology for timber production based on economic analysis and with regard to conditions of the processing plant.