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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Podpora JavaScriptu v zobrazovacím stroji HTML / JavaScript Support in an HTML Rendering Engine

Loskot, Radim January 2014 (has links)
This Master's thesis was written to create the extension for an experimental rendering engine CSSBox about scripting support in JavaScript language. In the theoretical section the thesis describes the architecture of the rendering engine and introduces problems of the scripting in HTML documents according to the recommended HTML 5 specification. This thesis deals with thorough analysis of existing scripting engines and their interfaces, which could be used for the extension implementation. Depending on the knowledge gained from the previous parts this thesis focuses only on the scripting engine Rhino and introduces an abstract design of its integration into the CSSBox project. At the end it evaluates the reliability and efficiency of the implemented functionalities and considers possibilities of their further development.
142

Simulátor Turingových strojů popsaných pomocí kompozitních diagramů / Simulator of Turing Machines Described by Means of Composite Diagrams

Siska, Josef January 2014 (has links)
In this thesis, the theory related to Turing machines and means of their description (with focus on composite diagrams) is presented. The aim of this work is to create an application that allows editing Turing machines described by means of composite diagrams and simulating their computation on specified input configuration (including non-deterministic and multi-tape machines). Furthermore, within the application it will be possible to run the termination analysis of Turing machine in order to determine whether this machine or any of its parts always halt. The resulting application is implemented in Java and the termination analysis is performed using the well-founded orders. And so, one of the results created during this work is a software tool which allows designing and testing of Turing machines described by means of composite diagrams. Resulting application may be used especially during lectures on theoretical computer science, where it can be used to demonstrate computation of some Turing machine.
143

Rizika skladování zásob náhradních dílů strojů a strojního zařízení ve výběhu / Risk of spare part of machines and equipment inventory control in decommissioning

Jirka, Lukáš January 2016 (has links)
This thesis deals with design of a suitable approach for managing the supply of spare parts for machines approaching decommissioning. The appropriate balance between outstanding risks related to equipment downtime and costs of holding spare parts is predicted by proposed systematic algorithm. Determination of key parameters affecting the whole process of spare parts inventory management and their subsequent use as a basis for Event Tree Analysis lead to finding an optimum set-up, which mitigates the overall impact of the planned reduction in spare parts storage levels. The new approach has a number of advantages including versatility of application for many types of machines, as well as a different outlook on a solution for the current issue in spare parts management.
144

Volba řezných nástrojů, podmínek a obráběcího stroje pro soustružení cívek / Choice of Cutting Tools, Conditions and Machine Tool for Turning of Coil

Skládaný, Jakub January 2016 (has links)
The purpose of work is to provide a manufacturing processes, cutting and machine tools for machining of small parts. The proposals are designed for high volume production with a maximum productivity. The first half is largely nature of the search, which analyzes issue of tools and machines for production of rotary parts. Further proposals are developed manufacturing processes for different types of machines including multi-spindle lathes. The main result of this work is to determine appropriate type of machine for the production of specified parts.
145

Analýza návrhu šroubového přípoje otočné desky kolesového skládkového stroje / Analysis of the design of the bolted connection pivot plate-wheel of bucket wheel stacker-reclaimerLoader

Šrajer, Jan January 2016 (has links)
This thesis describes an analysis of the design of the bolted connection pivot plate-wheel of bucket wheel stacker-reclaimer loader. The challenge solution is to decide whether the current design is suitable. The thesis contains comparison of calculation according to VDI regulation with the ČSN, performing stress analysis using FEM calculation model and a design of changes, joint bearings with steel structures.
146

Posouzení koncepce nového řešení kluzného kontaktu v elektrických strojích / Assessment of the design of the new solution sliding contact in electrical machines

Záhejský, Petr January 2016 (has links)
The thesis is devoted to assessing the concept of a new solution to the sliding contact in electrical machines. The work is focused mainly on the issue of collector engines, which are almost exclusively used in electric hand tools. Much of the work is devoted to angle grinders, which are usually used in extreme conditions and demands for seamless operation are enormous. In order partial insight into the problems in the introduction are studied phenomena acting on the sliding contact, wear and durability. Then further materials and diagnostic methods for increasing the transfer efficiency brush - commutator brush - ring. The following sections of this thesis is also considered a proposal innovated brush along with the practical verification and evaluation of the suitability of the use of innovative sliding contact.
147

Diagnostika vibrací elektrických strojů / Vibration diagnostics of electrical machines

Lexa, Jakub January 2016 (has links)
This thesis deals with vibration diagnostics of electrical machines. The thesis describes vibrations and their measurement. The next section concernes the diffrent modes of elctrical machines. Vibration of machines are divided into electrical causes and mechanical causes. Practical part deals with the measurement of vibration on the machines and their subsequent analysis. The result of the practical part is determining the fault of the measured induction motors.
148

Technické vylepšení obráběcího stroje NAKAMURA – TOME / Technical improvements of the machine tool NAKAMURA – TOME

Novák, Tomáš January 2016 (has links)
The subject of this engineer´s thesis is a design proposal for technical upgrade of chosen CNC turning center design groups. The choice of design groups is based on user´s and author´s practical knowledge gained from machine´s workings. For each of these groups, there is a function description, actual state of design solution and problematic behaviour description. The follow up consists of given problems solving with more possible variations taken into consideration, including economic evaluation of chosen solution.
149

Vybrané problémy s diagnostiky izolačních systémů točivých elektrických strojů / Selected Problems of Diagnosis of Insulation Systems for Rotating Electrical Machines

Pavlík, Josef January 2011 (has links)
This dissertation thesis deals with the measurement of insulation resistance for rotating electrical machines and polarization indices calculated from them. The first part contains a short theoretical introduction, methods of measurement and basic formulas for calculations. The second part discusses the results obtained in laboratory measurements in both the model and the real coil of high voltage machine. There are also elucidated some of the principles and causes of some phenomena with which the measurement of insulation resistance is encountered. The third part deals with the results of measurements on real machines. There are mainly discussed the dependences of insulation resistance and polarization index on the influences that occur in measurements such as temperature measured insulation, moisture in the insulation, but also the influence of measuring instruments on the measured values. It is also expressed how much these factors affect the measurement results. In addition, this part deals with some other influences that have a negative affect on the measurement of insulation resistance. There is processed a new methodology for measuring insulation resistence in the fourth part of this thesis. The need to develop a metodology of measuring is based on the needs of engineering practice, where is considerable inconsistency of measurement in the present time. Measurement, and often performed on the same machine, are not nowadays often comparable, because measurements are not met even the basic rules resulting from the findings of research and development, which were discovered in the last few decades. Measurement of insulation resistance in our nowdays methodology stagnated on the level of the seventies of 20th century. For this reason, we have developed a new methodology of measurement that takes into account all significant influences affecting the measurement. The purpose of the methodology is to ensure full repeatability and comparability of measurements not only on the same machine but on machines of the same type, in optimal cases, the machines of different types. There are the chapters "The objectives of the work" and "Conclusion" the part of the work. A very important chapter is "The contribution of thesis", which summarizes the original results of this work and results, the use of which is expected in engineering practice.
150

Analýza stability řezného procesu obráběcího stroje vzhledem k samobuzenému kmitání / STABILITY ANALYSIS OF CUTTING PROCESS OF MACHINE TOOL WITH RESPECT TO CHATTER

Vetiška, Jan January 2013 (has links)
The thesis deals with building and utilization of mechatronic models which are based on modeling of system of rigid and flexible bodies. Such models are then used for analysis of behavior of complex systems, for instance machine tools. The work is concentrated on analysis of self-excitation of a machine tool. The appearance of the self-excitation during the machining may be influenced by several methods described in the work. The evaluation of the appearance of the self-excitation is analyzed via so called lobe diagram. It is necessary to know transfer function describing the impact of acting forces on the deformation of the system (machine tool in this case) for compilation of the lobe diagram. The whole structure of the model shows compliant behavior which dramatically influences the transfer function thus the approach to the modeling of mechanical parts as flexible bodies is proposed. There are created models of modally reduced flexible bodies based on modified CAD models which have same modal properties as non-reduced FEM models up to the maximal excitation frequency. The reduced models have significantly lower number of degrees of freedom and it is possible to work with them in multi-body simulation tools and at the same time they contain the information about the deformations. The work utilizes Graig-Bamton method which is implemented to the ANSYS. The whole model is consequently built and analyzed in ADAMS. It is possible to export the linearized model of the system in form of state matrices which are used for writing of the transfer function. The conditions of stability of the machining process are then evaluated via the lobe diagram. The proposed thesis presents the modeling of mechatronic systems with stiff and rigid bodies. The approach may be used for analysis of machining tools as well as for development of advanced mechatronic systems with active damping, etc.

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