Research of Protective Coatings Application on Polymer Formulations Made by Additive Technology

Injection molding of polymer moldings has proven to be a fast way of making products for medium and high series production for many years. In order to produce a quality product, all stages of the process must be under control (tools, materials, injection molding machine, etc.). In the last two decades, additive technology for the production of prototypes and, more recently, finished products has been developing intensively. The biggest disadvantage of additive technology is the limited choice of polymer materials and different mechanical properties of products compared to products produced by injection molding technology. Making a mold for the injection molding process is time consuming and expensive, and for smaller batches, an unprofitable process. By making molds for injection molding with additive technology, we accelerate the process of production of finished products. One of the disadvantages of making molds in this way is their durability. In order to increase the durability of the mold, the area of coating application will be investigated. The research was conducted as part of the application for a doctoral thesis. The paper will be divided into three key sections. The first part of the paper will explain the research conducted so far. In the second part, the examination of the surface parameters that are necessary for us to obtain the connection between the additive material and the coating will be presented. Taking into consideration the first two units, the third unit will explain: the selection of the experiment plan, input factors, output factors as well as the method of conducting the experiment

Postupci primjene norme ISO/TS 29001:2010 u proizvodnim tvrtkama RH

Tvrtke koje posluju i djeluju u industriji kritičnoj s aspekta sigurnosti kao što je proizvodnja nafte i plina imaju potrebe za mnogo specifičnijim sustavom upravljanja kvalitetom od onog definiranog normom ISO 9001:2008. Sadašnji općeprihvaćeni standard sustava upravljanja kvalitetom ISO 9001:2008 koji je prihvaćen širom svijeta treba zadovoljiti potrebe i zahtjeve tvrtki različitih djelatnosti što zbog specifičnosti djelatnosti nije uvijek lako. Stoga je uspostavljena norma ISO/TS 29001:2010 kao rezultat direktne suradnje između organizacije ISO (International organization for Standardization) i industrije nafte i plina. Norma ISO/TS 29001:2010 predstavlja proširenje sveobuhvatno prihvaćene norme ISO 9001:2008 za sustave upravljanja kvalitetom, prvenstveno u dodatnim zahtjevima s aspekta prevencija nesukladnosti i smanjenja varijacija u realizaciji proizvoda, odnosno izvođenju procesa. Rad prezentira proces implementacije i certifikacije zahtjeva norme ISO/TS 29001:2010 u postojeći integrirani sustav upravljanja kvalitetom i okolišem hrvatske tvrtke IMG koja proizvodi visokotlačne igličaste ventile i ostalu tlačnu opremu za industriju nafte i plina. U radu se detaljno opisuju dodatni zahtjevi norme ISO/TS 29001 kao i način implementacije istih u tvrtku IM

Analysis of Surface Curvature Influence on 3D Scanning Accuracy of Dental Castings

The main goal of this study is determining the influence of surface curvature on 3D scanning accuracy of dental castings. The hypothesis is that 3D scanning errors occur on the geometry (surfaces) of a higher curvature on the dental anatomy. Ten dental castings (five mandibular and five maxillar) were 3D scanned with four different dental 3D scanners. As a reference device Atos Core industrial 3D scanner was used. Using a qualitative-quantitative approach of dividing every tooth in three areas (OS – occlusal surface, CSB – crown surface buccal side, CSP – crown surface palatal side) and observing the frequency of maximal deviation for each area a deviation map was obtained, which shows on what area, are the biggest deviations and in which frequency they emerge. In total 160 teeth were analysed. To conclude, 3D scanning errors occur more frequently on the geometry (surfaces) of a higher curvature on the dental anatomy. Future work suggests conducting a full numerical analysis to find a correlation between the accuracy of 3D scanned teeth surface and a surface curvature. Comparing the 3D scanning deviation to the calculated curvature of the surface could unveil which curvature is hard to 3D scan and generates errors

Uzroci radikalizacije terorista

Autorica obrađuje uzroke radikalizacije današnjih terorista, i to: s aspekta pravnih znanosti s područja sigurnosti, psihologije, sociologije, teologije, povijesti. Pritom se koristi sljedećim metodama istraživanja: analizom i sintezom sadržaja, komparativnom metodom te metodom generalizacije. Predmet istraživanja određen je po sadržaju i u užem smislu predstavlja uzroke radikalizacije džihadističkih terorista na području Europske unije, a vrijeme istraživane pojave kraće je od njezina trajanja. Prema postavljenoj tezi radikalne ideje ne dovode nužno do nasilnog radikalnog ponašanja

Measurement of casting parameters in ZnAlCu3 molds created by additive technology

This paper examines the parameters of casting ZnAl4Cu3 alloy (volume, castability, density and occupancy of the mold) in mold made additive technology. Molds made by additive technology are: cheaper in production of a small number of castings, geometrically more accurate and faster made. From obtained results of this paper it is clearly seen that printed mold must be protected with thermal coating because liquid adhesive of powder otherwise evaporates during casting and creates additional moisture in the mold, as it was noted

Modeling and Simulation of a Hard Real-Time Processor

Hard real-time systems are increasingly used in various areas of human activity justifying their implementation by means of specialized solutions, mostly of a suitable hardware/software combination. A frequently adopted approach to the realization of the hardware part is based on ASIC, usually a “general purpose” processor which operates according to real-time constraints. In this work the modeling of a processor for the hard real-time domain is described. It is structured as a collection of “task processors” being supervised by another one dedicated to the “kernel” functions. Specifically the behavior of the task processors is modeled using VHDL and subsequently simulated and tested. The paper also addresses the modeling process by determining the detailed requirements on the behavior of the task processor. The outcome of this step influenced the modeling process as the tools used were of restricted functionality and processor behavior enforced a particular decomposition. Because of a restricted VHDL subset available, it was necessary to model the task processor on the lowest level of behavioral abstraction. The task processor has been tested against chosen test programs written in an appropriate assembly language being specially developed for this purpose