Thesis is focused on design of production, material specifications and construction technology simplifications of school chairs and seats for developing countries. The use of locally available materials and equipment of local industry with application of low-technology manufacturing processes are emphasized. In developing areas this functional school furniture represents the basic comfort for pupils and facilitates the learning process. The thesis consists of three parts. The first part is focused on and deals with experimental assessment of mechanical parameters of various rectangular joint designs. In this case joints are stress-loaded in transversal direction. The second (practical part) of the thesis deals with designing the functional shape of seats with use of joints described and tested in the first part. The third part of thesis deals with manufacturing of designed chair model due to specifications mentioned in first part of thesis and also with design of simple tool for manufacturing the joints with low-end and low-cost technology. Further the thesis introduces my own design of simple seat construction made from massive wood material manufactured by low-end technology with regards to achieving the due specifications. The task of this thesis is to design the viable manufacturing process of seats and chairs from raw wood and scrap material. Essential part of thesis is also manufacturing of seat prototype and simplified model of proposed mortise and tenon drill. The thesis encloses the literature overview, experiment methodology, description of potentially usable and really used materials. In last chapter the testing results are summarized and the sample of manufacturing is documented.

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This thesis deals with the determination of mechanical properties of Norway spruce wood attacked by spruce bark beetle at various stages of damage by means of bending tested samples and impact strenght according to European standards. Due to the current occurrence of bark beetle calamities is only wood from these logs largely marketed. The main objective was to find out whether the wood affected by spruce bark beetle has comparable mechanical properties with undemaged wood and its subsequent use in construction as a construction timber. We did not notice any significant changes in the bending test where the modulus of rupture and modulus of elasticity of the wood affected by spruce bark beetle were comparable to those of the undamaged. On the contrary the impact strength test showed a decrease in the values for the maximum strength and toughness of the damaged wood compared to the undamaged. This shows us that wood affected by spruce bark beetle is becoming more fragile than undamaged trees. By done research we have found out that the bending strength of the wood affected by spruce bark beetle is not significantly different compared with undamaged trees. The theoretical part includes issues related to the testing of wood and its strength characteristics. Afterwards, there are listed the results of a statistical evaluation.

Master thesis analyzes rotary draw bending of the tubes without using a mandrel. Bending process is accompanied by many defects due to large displacement of formed material. One of the major defects is flattering of the cross section also called ovality. In order to decrease ovality comes up a proposal of the changes to the tool design. Modifications of tool’s geometry are numerically analyzed by finite element method in software ANSYS. According to the results of the simulations an optimized pressure die is manufactured. Several experimental tests are accomplished to verify the effect of the optimized tool design. Approximately 100 bends confirm a decrease of ovality using modified pressure die.

This diploma thesis deals with a mechanical analysis of bonded joints between timber and carbon fibres. Bending, shear and compression tests were chosen to describe the bonded joint's behaviour. The experiments were filmed by cameras for further evaluation of relative deformation and relative shear deforation, a well as movement. The measured data were used for analysis of deformation and specimen behaviour, comparison of different wood types and specimen results, and numerical three-dimensional model compilation.

Heat-treatment belongs to the most ecological methods of wood preservation methods and increase of its natural stability in exposition to outdoor conditions. Research of mechanical properties opens new possibilities of thermowood usage in general. Wood appertains to viscoelastic materials and due to long-term loading creeps. There currently rise both elastic deformation, deformation elastic in time and plastic deformation. Partially there are irreversible changes due to stress even after unloading. This work presents first insight to the matters of thermowood rheology and inspects its behavior under long-term loading in bending. This paper compares ratio of these three types of deformation in untreated wood and thermally modified wood in seven different temperatures (140; 160; 180; 190; 200, 210°C). The samples were exposed to 600 hours applied loading covering 40% of ultimate stress (modulus of rapture). Test were performed under constant conditions in special creep units in conditioning kiln. Increasing deformation under constant load was analyzed by Burger rheological model. The results show that samples treated under lower temperatures (140 and 160°C) exhibit greater creep than untreated wood. This result is positive for structural usage of wood. On the other hand the samples treated under higher temperatures levels (200 an 210°C) display deterioration of mechanical properties. This is due to changes in wood structures caused by heat-treatment. The most important impact of this work goes to future research of this field. Next development has to apply for the best quality of samples and also select rather prismatic parallelism than transversal one. Also application of 40% ultimate stress loading appeared as too high and together with wood defects led to destruction of samples.

KAMENÍK Tomáš: Bending technology profile of steel The project has been elaborated within the master's of studies of the subject M-STG manufacturing technology and it presents the lay-out of the bending technology profile of steel from the material S235JRG2. The bend is made by the bending and the press tools. The press tools and the bending profile were suggested on the bases of the literature study of technology bending. In consideration of the calculated bending power and the dimension profile will be made profile on the hydraulic press CYS 320 ( the manufacturer ŠMERAL Brno a.s.). At the end of the the thesis there are performed calculations of the technical and economic evaluation for the machine press and the bending .

This diploma thesis deals with the effects on a type of selected wood joint within a specific exposure to natural external climatic conditions on the 3-point bending strength of the bonded joint. The solid robinia wood specimens were glued together with one component polyurethane adhesive. The specimens were joined in width using finger joint, edge joint and dowel joint. The glued joints were exposed to natural external climatic conditions for eight months and later tested for flexural strength every two months.

The master thesis deals with the influence of heat treatment and storage time on microstructure and mechanical properties of 26MnB5 steel, which is used in the production of tubular components in the quenched and tempered state. The objective was to increase the plasticity of the steel by the definition of new process parameters of the induction heat treatment line. New tempering diagrams of 26MnB5 steel for two various speeds of the heat treatment line were established and used to determine new tempering temperature and speed of the heat treatment line. Observation of the influence of storage time on mechanical properties of the steel did not reveal that it is liable to ageing.

Title: Theoretical studies of rolled-up and wrinkled nanomembranes Author: Mgr. Peter Cendula Department: Department of Condensed Matter Physics Thesis Supervisors: Prof. Dr. Oliver G. Schmidt, Prof. RNDr. Václav Holý, CSc. Abstract : The thesis is devoted to three similar topics from the field of rolled-up and wrinkled nanomembranes. We start by recalling classical theory of thin plates, which will be used to describe deformation of nanomembranes. In the first topic, relaxation of internal strain is studied when a flat film is partially released from the substrate by etching the sacrificial layer underneath. Energetic competition of the tube and wrinkle shape is quantitatively investigated. Similar model is used to investigate the limiting maximum value of tube rotations. In the second topic, roll-up of initially wrinkled film is shown to favor tubes forming on the flat edge of rectangular wrinkled pattern, enabling precise control of tube position. Experiment is provided to justify our theoretical predictions. In the third topic, quantum well is assumed inside a wrin- kled nanomembrane. Shift of transition energy induced by lateral modulation due to bending strain is quantified, being of interest for strain-sensitive optical detectors and emitters. In addition, lateral localization of electron and hole due to...