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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.
51

Optimalizace rozvozu a svozu infuzních roztoků / Optimization distribution and collection of infusion solutions

Kravciv, Zbyněk January 2009 (has links)
There are many distribution tasks, that vary in a number of vehicles, time windows, dividend or undivided delivery or if it is static problems or dynamic problems. In this essay I focus just on few of them. At first I put my mind to simple statistic distribution task with one vehicle. Later I extend it with time windows, when the point can be served by one car and by many cars. In the essay it will be solved the real task of distribution and delivery transportation of infusion in the hospitals. Because of the difficulty of solution I have to use the heuristic methods - Method of nearest neighbour, Savings method and Insert method. All these methods are modified by capacity requirements, time windows and also observence of the rules, which the drivers have to keep during a distribution. The aim is to minimize the distance travelled by the vehicles. And at least the company could be recommended the best solution.
52

Leia (e entenda) a bula: estudo da compreensibilidade em bulas de medicamentos brasileira e alemã / Read (and understand) the package insert: study of the comprehensibility in Brazilian and German package inserts

Cintra, Adriana Dominici 23 September 2015 (has links)
Nesta dissertação, foi desenvolvida uma análise linguística contrastiva de bulas de medicamento brasileiras e alemãs. O principal objetivo dessa análise era identificar o grau de compreensibilidade de cada um dos textos, segundo as dimensões do modelo de Karlsruhe: Concisão, Correção, Motivação, Estrutura, Simplicidade e Perceptibilidade. Para isso, foram retomados conceitos da Linguística Textual e procedimentos da Textologia Contrastiva, como as definições de texto e gênero textual, o método de comparação de textos paralelos e o estabelecimento de um termo de comparação. De maneira geral, os resultados da análise contrastiva indicaram que termos técnicos (no âmbito da simplicidade) e fonte pequena (no âmbito da perceptibilidade) não são as principais causas de incompreensão na leitura das bulas, como se supôs inicialmente. O estudo evidenciou que desvios na estrutura e na concisão das bulas podem ter um impacto tão ou mais negativo na compreensão desses textos do que os aspectos anteriormente citados. Além disso, foi possível constatar que cada uma das dimensões possui um peso diferente na compreensibilidade das bulas analisadas devido a diferenças linguísticas e culturais entre os pares alemão/português e Alemanha/Brasil. / In this research, a contrastive linguistic analysis of German and Brazilian package inserts was developed. The main aim of this analysis was to identify the degree of comprehensibility in each text, according to the Karlsruhe model dimensions: concision, correctness, motivation, structure, simplicity and perceptibility. To achieve this aim, it was necessary to review some concepts of the Textual Linguistics and procedures of the Contrastive Textology, such as the definitions of text and textual genre, the method of comparing parallel texts and the establishment of a point of comparison. In general, the results of the contrastive analysis have shown that technical terms (in the scope of simplicity) and small font (perceptibility) are not the main causes of misunderstanding of package inserts, as it was supposed initially. The study has highlighted that deviances in the structure and in the concision of package inserts may have an impact in the comprehension of these texts as negative as the aspects forementioned, if not more. Moreover, it was possible to notice that each dimension has a different weight in the comprehensibility of the analyzed package inserts because of the linguistic and cultural differences between German/Portuguese and Germany/Brazil.
53

Volba optimálního nástroje pro vybranou technologii obrábění / Selection of an optimal tool for the selected machining technology

Podstata, Jan January 2020 (has links)
This thesis compares the properties of four types of replaceable cutting tool inserts from different suppliers during milling. The comparative factors are cutting force, material loss of the insert and the roughness of the resulting surface. The thesis is divided into two parts - a comprehensive overview of the current state of knowledge and an experiment. The first part analyzes the load, the possibility of its measurement, surface treatment of tools, milling cutters and replaceable inserts. The experiment took the form of measuring the load during face milling, measuring the surface roughness of the machined material and measuring the material loss of the inserts on an optical strain gauge. The replaceable cutting tool inserts were compared based on the performed measurements.
54

Aplikace elektroerozivního hloubení při technologii výroby vyměnitelných břitových destiček SK / The application of electrical discharge sinking at technology of production of indexable insert cemented carbide

Gábor, Radek January 2008 (has links)
This diploma thesis view to problem electrical discharge sinking. Forth with deal production of indexable insert cemented carbide and application electrical discharge sinking at this technology.
55

Moderní řezné nástroje ze slinutých karbidů / Modern cutting cemented carbide tools

Štefek, Jaromír January 2010 (has links)
This thesis deals with modern cutting cemented carbide tools. In the first section are stated several basic innovations already used tools for basic machining operations, which is turning, milling and drilling. It continues with analysis of single materials for production of cemented carbides, non coated as well as coated and with comparing of their properties. There are listed the basic cutting properties of the cutting tools after that. The penultimate point of the work is optimization of the basic machining operations, namely roughing and finishing, for a given application, which is in this case turning on the lamp stand. Finally, everything is summed up and evaluated in the conclusion.
56

Výroba závitové vložky objemovým tvářením / Bulk forming technology of thread insert

Ostřížek, Lukáš January 2010 (has links)
OSTŘÍŽEK Lukáš: Bulk forming technology of thread insert The Master's degree project, 2nd form, summer semester, academic year 2009/2010, educational group 5O/60 Mechanical Engineering - Manufacturing Technology, Brno University of Technology, Faculty of Mechanical Engineering, Institute of Manufacturing Technology, Dept. of Metal Forming and Plastics, May 2010. This project solves the manufacturing process of " Thread insert " part by technology of bulk forming. Part is made of 11 320 5R steel. Semifinished product has cylinder shape with dimensions of O13,5h11 – 9,1±0,2 mm. This part is made during five bulk forming operations on the HATEBUR AKP 3-5.
57

Trvanlivost destiček ADMX při frézování materiálů skupiny S / Tool life of ADMX inserts for milling of the S-grade materials

Tejkl, Jakub January 2014 (has links)
This diploma thesis studies the machining of group S materials. In the theoretical part of this thesis these materials were divided into groups and subsequently analyzed. These materials were also analyzed in terms of their impaired machinability. In the practical part of this thesis experimental tests were conducted to determine tool life, tool wear and in the case of testing titanium alloy surface roughness too.
58

Konstrukce stanice pro montáž závitových vložek do automobilových klik / Design of stand for assembly of screw-inserts into car door handles

Kulčar, Vojtěch January 2014 (has links)
The subject of this thesis is design of stand for assembly of srew-inserts into car door handles. It contains of search of possible technical solutions of part handling and available technologies of screw-insert instalation. In design part of thesis contains of analysis of construction and choice of technologies. In construction part of my thesis u can find description construction of stand and risk analysis of this machine. Moreover there are calculations, drawings of main assemblies of machine and model of stand modeled in Autodesk Inventor.
59

Moderní technologické prvky pro trubkové výměníky tepla / Modern technological elements for tubular heat exchangers

Plánková, Tereza January 2020 (has links)
The aim of this diploma thesis is to get acquainted with modern technological elements currently used in shell-and-tube heat exchanger in the shell-side and tube-side, thermal-hydraulic calculation of selected elements and comparison of thermal-hydraulic properties with classically used competing technological elements. The work deals mainly with EM baffle in the tube-side and tube inserts like the twisted tape type (and its modifications) and coiled wire in the tube-side. The theoretical part is focused on acquaintance with classical technological elements in shell-and-tube heat exchanger and with basic thermal-hydraulic calculations, practical part then on acquaintance with modern elements and thermal-hydraulic calculation of selected elements. These calculations are then compared with the results of the thermo-hydraulic calculation of similar elements.
60

Efeito de tratamentos térmicos em insertos de assentos de válvulas sinterizados / Effect of heat treatments on sintered valve seat inserts

Gomes, Maurilio Pereira 28 August 2017 (has links)
Atualmente, uns dos grandes desafios para a indústria automobilística é aumentar o desempenho do conjunto mecânico responsável por selar a câmara de combustão interna de motores automotivos e também reduzir os seus custos de obtenção. O objetivo deste trabalho foi o de tratar termicamente insertos de assentos de válvulas (do inglês valve seat insert, VSI) obtidos pela rota de metalurgia do pó. Esta técnica possibilitou a substituição do cobalto e do chumbo, devido ao seu elevado custo e efeito toxicológico, respectivamente. Ao longo do trabalho foram avaliados VSI obtidos com três misturas de pós diferentes, sendo que os elementos comuns nestas três misturas foram os pós de ferro, sulfeto de manganês, carboneto de nióbio, grafite, estearato de zinco e cobre. Em cada uma destas misturas variou-se apenas os tipos de pós de aços rápidos e aço ferramenta utilizado, sendo estes o aço rápido AISI M3:2 (Mistura 1), aço rápido AISI M2 (Mistura 2) e aço ferramenta AISI D2 (Mistura 3). Os tratamentos térmicos aplicados aos VSI consistiram em têmpera ao ar e têmpera ao óleo, ambas seguidas de duplo revenimento em sete temperaturas equidistantemente diferentes, variando de 100 °C a 700 °C. Os ciclos dos tratamentos térmicos foram determinados por meio da utilização de termopares do tipo k acoplados à um sistema de aquisição de dados. As propriedades físicas e mecânicas dos VSI foram determinadas através da dureza aparente, densidade aparente e resistência à ruptura radial. A caracterização microestrutural foi realizada utilizando-se a microscopia óptica e microscopia eletrônica de varredura. A composição química foi determinada por meio da análise elementar e por espectrometria de fluorescência de energia dispersiva de raios X. Os melhores resultados em relação às propriedades mecânicas dos VSI foram obtidas para os insertos temperados ao ar e duplamente revenido a 600 °C para a Mistura 1 e Mistura 2, e a 500 °C para Mistura 3. Já para a têmpera ao óleo, as melhores respostas foram para os VSI obtidos com a Mistura 1 duplamente revenida a 400 °C e a, 300 °C para os componentes obtidos com a Mistura 2 e Mistura 3. / Currently, one of the biggest challenges for the automobile industry is to increase the performance of the mechanical set responsible for sealing the internal combustion chamber in automotive engines and reduce its cost of production. The aim of the present work was to heat treat valve seat inserts (VSI) obtained through the powder metallurgy route. This procedure made possible the substitution of cobalt and lead, due to its high cost and toxicological effect, respectively. Throughout the work, it was evaluated VSI obtained with three different types of powders mixtures, and common elements at the three different powders mixtures were iron powder, manganese sulfide, niobium carbide, graphite, zinc stearate and copper. In each of these powders mixtures, it was changed only the type of high-speed steels and tool steel, consisting of high-speed steel AISI M3:2 (Mixture 1), high-speed steel AISI M2 (Mixture 2) and tool steel AISI D2 (Mixture 3). The heat treatments applied to the VSI were air quenching and oil quenching, both followed by double tempering at seven different equidistantly temperatures, ranging from 100 °C up to 700 °C. The heat treatments thermal cycles were determined using a thermocouple type k attached to a data acquisition system. The physical and mechanical properties of the VSI were measured in terms of apparent hardness, apparent density and crush radial strength. Microstructural characterization was performed using optical and scanning electron microscopy. The chemical composition was determined using gas analysis and energy dispersive X-ray fluorescence spectrometry. The best results regarding the mechanical properties of the VSI were obtained for the VSI air-quenched and double tempered at 600 °C for the powder Mixture 1 and Mixture 2, and at 500 °C for Mixture 3. For the oil quenching, the best response was reached for the VSI obtained with Mixture 1 double tempered at 400 °C, and at 300 °C for the components obtained with Mixture 2 and Mixture 3.

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