The main objective of this research is to establish a connection between orthodontic mini-implant design, pull-out force and primary stability by comparing two commercial mini-implants or temporary anchorage devices, Tomas®-pin and Perfect Anchor. Mini-implant geometric analysis and quantification of bone characteristics are performed, whereupon experimental in vitro pull-out test is conducted. With the use of the CATIA (Computer Aided Three-dimensional Interactive Application) CAD (Computer Aided Design)/CAM (Computer Aided Manufacturing)/CAE (Computer Aided Engineering) system, 3D (Three-dimensional) geometric models of mini-implants and bone segments are created. Afterwards, those same models are imported into Abaqus software, where finite element models are generated with a special focus on material properties, boundary conditions and interactions. FEM (Finite Element Method) analysis is used to simulate the pull-out test. Then, the results of the structural analysis are compared with the experimental results. The FEM analysis results contain information about maximum stresses on implant–bone system caused due to the pull-out force. It is determined that the core diameter of a screw thread and conicity are the main factors of the mini-implant design that have a direct impact on primary stability. Additionally, stresses generated on the Tomas®-pin model are lower than stresses on Perfect Anchor, even though Tomas®-pin endures greater pull-out forces, the implant system with implemented Tomas®-pin still represents a more stressed system due to the uniform distribution of stresses with bigger values.

The main objective of this research was to propose a light and practical design solution for electric bike front drive with bottom bracket electric motor. The initial design needs to be redesigned so it can enable simultaneous use of the electric drive and pedal drive, with integration of the front gear shifter. After gathering the basic information linked to the problem and inspecting the initial design solution, the assets and flaws have been identified. The CAD models of the considered possible solutions were developed into FEM models which were used for structural analysis in CAD/CAE software system CATIA. On the basis of the FEM analysis and additional criteria, the optimal solution was chosen, and structural optimization, based on FEM model, was performed. A prototype was manufactured and a mounting process in a place of the initial design was performed. Afterwards, electric bike with mounted prototype was tested under real conditions.

Intensive utilization of computers is especially emphasized in the field of industrial production, where use of computer applications achieves significant savings in regard to the time required for manufacturing of products. Shortening of the production time decreases the production costs and new products are faster introduced to the market, thus making the company more competitive. In addition to the shorter time for production, better precision and accuracy is also accomplished, resulting with better product quality at the end. Due to the fact that, for the reason of cost-effectiveness of manufacturing of tools, processing of sheet metal on presses is primarily performed in the course of serial production, this paper focuses on an analysis of the use of computers in the process of design of tools for punching and cutting of sheet metal on presses. The presented methodology encompasses all phases in the process of design of tools – from planning the work piece until the final design of the tool for punching and cutting, with an emphasis on the activities performed exclusively by computer applications. The result of this research is a 3D geometrical model of a tool for punching and cutting, with an explanation of characteristics of its construction parts, calculation of its executive parts, analysis and simulation of operation of the tool, and finally the conclusion on the representation and importance of the utilization of computer applications in the process of design of such tools.