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61	Approche granulaire des objets pédagogiques en vue de l'adaptabilité dans les EIAHs Battou, Amal, Cherkaoui, C., Mammass, Driss 21 January 2012 (has links) (PDF) Le travail que nous présentons dans cette thèse s'intègre dans une problématique générale des Environnements Informatiques pour l'Apprentissage Humain (EIAH). Il s'intéresse plus particulièrement aux Systèmes Hypermédias Adaptatifs Dynamiques (SHAD). Le but principal est d'examiner l'intérêt de la granularité fine pour l'adaptation des parcours dans ces systèmes. Il s'agit, en fait, de la génération automatique de cours adaptés à un apprenant particulier, à partir d'un ensemble de ressources pédagogiques et en fonction de ses besoins, ses préférences et ses pré-requis. Les ressources pédagogiques appelés actuellement objets pédagogiques sont indexés en utilisant des normes et des standards de métadonnées éducatifs comme LOM et SCORM. Ces objets pédagogiques, qui constituent le contenu à apprendre, sont assemblés à partir de grains pédagogiques puis associées pour constituer des parcours individuels de formation avec une présentation de type hypermédia. Nous proposons dans le cadre de ce travail, une nouvelle approche de la granularité des ressources pédagogiques basée sur la taille, le contenu et le type de média utilisé. Cette modélisation granulaire propose une décomposition du contenu en fragments ou grains pédagogiques de type introduction, définition, exemple, remarque, etc. Chacun de ces fragments est représenté par des briques multimédia de type : texte, image, son, vidéo, etc. Tous ces éléments servent à améliorer l'adaptabilité, à la fois du contenu, de sa présentation et de la navigation dans un environnement d'apprentissage hypermédia. En résumé, à partir d'un ensemble de ressources élémentaires et granulaires, de leurs descriptions sémantiques et du profil de l'apprenant, le système attendu doit être capable de générer des ressources adaptées (cours, exercices, etc.) avec une interface de navigation sur le Web. Dans ce sens nous avons mis en place les premières briques de réalisation d'un SHAD, que nous avons baptisé Adaptive Learning System for the "C" Programming Language (ALS-CPL). Ce système spécifique vise tout d'abord à mettre en application nos recherches sur les environnements d'apprentissage de programmation, dans le cadre d'un large projet intitulé Adaptive Learning System for Programming Languages (ALS-PL). Il a également pour but particulier de mettre en pratique l'approche granulaire des contenus pour l'adaptabilité. EIAH SHAD granularité fine adaptabilité ressources pédagogiques objets pédagogiques normes standards metadonnées LOM SCORM parcours individuel profil de l'apprenant ALS CPL ALS-PL
62	Systém navigace pomocí GPS pro účely cementárenské technologie / GPS Navigation system for cement technology Mináč, Ján January 2009 (has links) This diploma work deals with proposal and implementation GPS navigation system. Work includes described basic types of cement quarry and proposal to create mathematical and software model of quarry. Then work is devoted to possibilities of basic described algorithms for searching the shortest way in graph and two algorithms are described. They are Floyd-Warshall and Dikjstra algorithms. The work describe implementation of Dijkstra algorithm to model of quarry and description of the programs Autec RouteEditor and AQL Control Library. MINÁČ, J. GPS navifgation system for cement for cement technology. Brno: Brno university of technology, Faculty of electrical engineering and communication, 2009. 90 p. Supervisor prof. Ing. František Zezulka, CSc.
63	Římské lázně a saunový svět / Roman spa and sauna world Olšáková, Pavla January 2014 (has links) The specified location for the design is located in the street Hády near the former quarries -Hády and Růženin lom. The place is surrounded by suburban recreational greenery and has sufficient accessibility. On a dedicated site is considered new and existing applications. The new use of the buildings includes a water park and Roman bath and the sauna world. The building of the Roman bath and sauna world will contain, in addition to the main operations also ancillary services and hydrotherapy treatments. The object is oriented at the southern edge of the land between the parking lot and the building of the Aqua Park. The object is designed as a three-storey with basement (1S), 1st floor (1NP) and 2nd floor (2NP). Mass solution is the arc plan. The input section is designed as a contiguous solid mass. The rear part is then designed as two separate halls. From the perspective of the construction is a reinforced concrete skeleton. Surface materials are plaster with metallic paint, glass and wood.
64	Vliv zakončení výztužné lopatky u Francisovy turbíny na tvorbu Karmánových vírů / Influence of the Francis turbine stay vane trailing edge shape on generation of Karman vortex street Novotný, Vojtěch January 2015 (has links) In the flow past bluff bodies for a certain range of velocity a periodical vortex shedding emerges which is known as von Kármán vortex street. This phenomenon causes the periodical alteration of pressure field which affects the body. Should the vortex shedding frequency be similar to the body natural frequency, the amplitude of vibration significantly increases which can lead to fatigue cracking. In the case of water turbines, this phenomenon often affects the stay vanes. Both the vortex shedding frequency and the lift force amplitude can be influenced by the modification of the trailing edge geometry. The aim of this thesis is to use CFD computation in order to find the optimal geometry of the stay vane trailing edge for the specific Francis turbine unit.
65	Analýza účinku koncentrace slunečního záření na degradaci tepelných izolací ve skladbách plochých střech / Analysis of effect of solar radiation concentration on the thermal insulation degradation in the flat roof construction Židek, Ondřej January 2016 (has links) The master´s thesis analyzes influence of direct and reflected solar radiation to heat strain and degradation of thermal insulation in the flat roof construction. In many building was a problem in a significant degradation of thermal insulation made from expanded polystyrene in the vicinity of glass surfaces. To determine the causes of this problem, it was necessary to study and test the properties of building materials and the physical nature of the effect of solar radiation on the building structure. In the introductory section lists the cases of buildings with degradation of thermal insulation and existing knowledge on this issue. The theoretical part describes the technical properties of thermal insulating materials used in the flat roof construction, nature and division of solar radiation, optical laws of light reflection and physical theory to explain the technical thermal behavior of building materials and structures. The last part describes a practical model and analyzing measured data in thermal stress in the flat roof construction. The practical part also determines the importance of different influences configuration structures using to dynamic simulations. At the end of the practical part they are validated theoretical knowledge obtained by analyzing data from a practical model.
66	Welds in the lean duplex stainless steel LDX 2101 : effect of microstructure and weld oxides on corrosion properties Westin, Elin M. January 2008 (has links) Duplex stainless steels are a very attractive alternative to austenitic grades due to their higher strength and good corrosion performance. The austenitic grades can often be welded autogenously, while the duplex grades normally require addition of filler metal. This is to counteract segregation of important alloying elements and to give sufficient austenite formation to prevent precipitation of chromium nitrides that could have a negative effect on impact toughness and pitting resistance. The corrosion performance of the recently-developed lean duplex stainless steel LDX 2101 is higher than that of 304 and can reach the level of 316. This thesis summarises pitting resistance tests performed on laser and gas tungsten arc (GTA) welded LDX 2101. It is shown here that this material can be autogenously welded, but additions of filler metal, nitrogen in the shielding gas and use of hybrid methods increases the austenite formation and the pitting resistance by further suppressing formation of chromium nitride precipitates in the weld metal. If the weld metal austenite formation is sufficient, the chromium nitride precipitates in the heat-affected zone (HAZ) could cause local pitting, however, this was not seen in this work. Instead, pitting occurred 1–3 mm from the fusion line, in the parent metal rather than in the high temperature HAZ (HTHAZ). This is suggested here to be controlled by the heat tint, and the effect of residual weld oxides on the pitting resistance is studied. The composition and the thickness of weld oxide formed on LDX 2101 and 2304 were determined using X-ray photoelectron spectroscopy (XPS). The heat tint on these lean duplex grades proved to contain significantly more manganese than what has been reported for standard austenitic stainless steels in the 300 series. A new approach on heat tint formation is consequently presented. Evaporation of material from the weld metal and subsequent deposition on the weld oxide are suggested to contribute to weld oxide formation. This is supported by element loss in LDX 2101 weld metal, and nitrogen additions to the GTA shielding gas further increase the evaporation. / QC 20101126 Duplex stainless steel welding weld metal HAZ nitrogen manganese austenite formation phase balance precipitates pitting resistance heat input solidification element loss evaporation deposition weld oxides discoloration mechanical properties thermo-mechanical simulation Geeble GTA laser LOM SEM EDS TEM Leco EPMA ferroxyl test XPS post weld cleaning pickling Materials Engineering Materialteknik
67	Napjatostní aspekty kvazikřehkého lomu / Stress state aspects of quasi-brittle fracture Sobek, Jakub January 2015 (has links) The presented dissertation thesis is focused, as the title suggests, on the analysis of stress state aspects of quasi-brittle fracture. That means the fracture of composite materials with cement matrix (such as concrete, mortar, plaster, etc.), ceramics and other composites. Used methods are based on the theory of multi-parameter linear elastic fracture mechanics, which highlights the importance of considering of several initial terms of Williams power series, approximating the stress and displacement fields in a cracked body, within conducted fracture analyses. Determination of values of coefficients of terms of this series, recalculated into the shape functions serving in most of the conducted stress state analyses, is performed via the so called over-deterministic method. Another tool for the problem solving is nonlinear fracture mechanics, represented primarily by the cohesive crack model, namely the crack band model implemented in the used ATENA software. For the backward reconstruction of stress field in the cracked bodies the application ReFraPro is used. The analytical part deals with various aspects of wedge-splitting test – from the boundary conditions, though various possibilities of nodal selection (required as input variables for the over-deterministic method) up to the advanced (automated) analysis of numerical model. Special chapter includes atypical test specimens designed for adjusting of various levels of constraint of stress and deformation at the propagating crack tip. The study of this geometry and also the subsequent detail analysis reveals important information for real experiments. Backward reconstruction of stress field presents analysis on suitable possibilities of nodal selections as inputs into the procedure of approximation of the crack tip fields and answers the question of the necessity of application of the multi-parameter linear elastic fracture mechanics for certain fracture analyses of specimens from quasi-brittle materials. The th
68	Friction and wear study of lean powder metallurgy steel in a lubricated sliding contact Lejonklo, Caroline January 2019 (has links) A fairly new technology used to produce metallic components is powder metallurgy (PM). Among the advantages with this technique are decreased cost of production for complex-shaped parts, new alloys are made possible, reduced end processing, less material loss, and vibrational damping effects. The downside is the number of pores created which can alter the tribological properties of the material. The focus of this report is to investigate how lean PM steel behaves under tribological contacts. Friction and wear will be investigated using a pin-on-disc setup to mimic the sliding part of a gear tooth mesh. Previous studies show that the amount of wear, and if the wear increases or decreases with increased density is dependent on the degree of porosity and the pore size. This means that the wear might be minimized by optimizing the number of pores in the material and their shape and size. The result of this study shows that the friction coefficient decreases with increasing density. The wear coefficient show signs of the same correlations but further tests are needed. The main wear comes from adhesive wear, with signs of abrasive wear. The amount of abrasive wear seems to increase with an increase in density, supporting previous studies claiming that pores can trap wear debris and decrease the number of abrasive particles in the contact. Lean steel Powder metallurgy (PM) Powder metallurgy steel (PM steel) Friction Wear Sliding contact Lubricated Porosity Tribology Adhesive wear Abrasive wear Gear Gear tooth Particles Polyalphaolefin 8 (PAO 8) Contact pressure Density Light optical microscopy (LOM) Scanning electron microscopy (SEM) Vertical svanning interferometry (VSI) Pin on disc Pin-on-disc Materials Chemistry Materialkemi Inorganic Chemistry Oorganisk kemi Other Chemistry Topics Annan kemi Other Engineering and Technologies Annan teknik Chemical Engineering Kemiteknik Materials Engineering Materialteknik
69	Ohýbaná tělesa: Numerická podpora v software ANSYS / Bend specimens: Numerical support in software ANSYS Viszlay, Viliam January 2016 (has links) The aim of the thesis is the investigation of fracture-mechanics parameters on specimens made of quasi-brittle materials. The principles of two-parameter fracture mechanics are used. Couple of numerical simulations were done and their outputs are used for two main analysed specimen geometries. For simulations the finite element method software ANSYS is used. In the first part, the thesis focuses on bended specimens. The influence of different geometric parameters on fracture mechanics behaviour of cracked specimen is investigated. For model calibration the outputs of other authors are used. In the second part the specimens for modified compact-tension test (CT test) are analysed. Similar to the first part, the influence of geometric parameters of the specimen (in this case, the specimen size) on fracture mechanics parameters were investigated. The modified CT test was derived from CT test which is commonly used for metal materials testing as the suitable geometry for cement-based composite materials testing. The outputs of both parts are calibration polynomials, which are expressions obtained for different specimen geometries, giving the value of fracture mechanics parameter as the function of specimen geometry. As the example, calibration curves are used to obtain fracture toughness of tested material using the outputs from recent experiment.

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