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V diplomski nalogi sem obravnaval dve definirani paličji, kjer so prvo paličje sestavljali odprti prerezi z vijačenimi spoji (tradicionalna zasnova). Drugo paličje so sestavljali zaprti prerezi (cevi) z varjenimi spoji. Paličji sem analiziral z globalno elastično analizo. Pri modeliranju vozlišč sem vsako paličje razširil na tri različne tipe vozlišč. Prvi model je temeljil na principu togih vozlišč z oznako (RMT), drugi model na principu togega pasu po celotni dolžini, kjer so polnilni elementi priključeni členkasto (RMK), tretji model pa je na principu členkastih vozlišč (RMČ). Zasnoval in dimenzioniral sem elemente in vozlišča vseh modelov. Obtežba je bila podana in je bila enaka za vse modele. Namen te diplomske naloge je bila primerjava rezultatov pri dveh različnih zasnovah s tremi različnimi modeliranji vozlišč. Postopki kontrol pri nosilcu iz cevi so veliko bolj enostavni in transparentni kot pri tradicionalni zasnovi. Pri modeliranju vozlišč se notranje statične veličine in rezultati kontrol nosilnosti ne razlikujejo veliko glede na različne modele. Vsi modeli imajo zadostno duktilnost za razvoj rotacij, ki so majhne. Kontrole nosilnosti pri modelu s togimi vozlišči se ponekod zapletejo na račun razvoja sekundarnih momentov, ki so majhni. Najboljša opcija za projektiranje je bilo paličje sestavljeno iz cevi po modelu (RMK). The diploma thesis deals with analysis of two defined trusses. The first truss is assembled with open cross sections with bolted connections (traditional design), while the second one is assembled with welded tubes. Both trusses were analysed with the elastic global analysis. While designing the trusses, each truss was expanded according to three different types of nodes. The first design was based on the numerical model with rigid nodes (RMT), the second design on the model with continuous upper and lower chords, while the verticals and diagonals were hinged to the chords (RMK), the third design was based on the model considering ideal truss system (RMČ). The purpose of this thesis was to compare the results of two different truss structures with three different numerical models. The control procedures for the tubular truss beam were much simpler and more transparent in comparison to the structure with angle and U profiles. The internal forces were similar in all cases. Both structural systems had sufficient ductility to develop rotations and therefore reduce the secondary moments.. The design of bolted joint was complicated, because the secondary moments and the moments due to load eccentricity had to be taken into account. For this reason, the truss made of tubes was better option.

V diplomskem delu smo opisali podjetje Impol PCP, d. o. o., eno izmed trinajstih podjetij v družbi Impol, d. o. o. Impol ima večletno tradicijo, ustanovljen je bil že leta 1825. V tem času, se je podjetje razvijalo in širilo, sedaj ima tudi podjetja v Srbiji ter na Hrvaškem. Podjetje se ukvarja s predelavo aluminija. Kot problem v diplomskem delu smo izpostavili nepotrebne manipulacije med proizvodnim obratom in skladiščem ter tudi skladiščenjem samim. Predlagamo novo nakladalno ploščad, s katero bi se izdatno zmanjšale manipulacije med proizvodnim obratom in skladiščem. Izračunali smo tudi čas, v katerem naj bi se investicija, ki bi jo podjetje namenilo za novo nakladalno ploščad, tudi povrnila. In this diploma, we described the company Impol PCP d.o.o., one of the thirteen companies in the company Impol d.o.o.. Impol deals with the processing of aluminum. Impol has a long tradition, it was founded in 1825. At this time, the company has developed and expanded, and now there are companies in Serbia and Croatia. As a problem in the diploma we pointed out the unnecessary manipulations between the production and the warehouse, as well as the storage in the warehouse itself. We tried to solve this problem by suggesting that we need a new loading dock, which would reduce manipulation between the production plant and the warehouse. We also calculated the time whenh this investment intended for the new loading dock could be repaid.

In order to obtain input data for numerical simulations of tube forming, the material properties of tubes need to be determined. A tube tensile test can only be used to measure yield stress and ultimate tensile stress. For tubes with a large diameter/thickness ratio (D/t), tensile specimens are cut out and processed in a similar way as with sheet metal. However, for thin tubes with a diameter/thickness ratio below 10, the tensile specimens could not be cut out. The flow curve of the analyzed tube with a small diameter and D/t ratio of 7 was determined with a ring-shaped specimen. The experimental force-travel diagram was acquired. A reverse-engineering method was used to determine flow curves by numerical simulations. Using an L$_{25}$ orthogonal array of the Taguchi method different flow curve parameters and friction coefficient combinations were selected. Tube upsetting with determined parameter combinations was performed with the finite element method. With analysis of variance influential equations among selected input parameters were determined for the force levels at six upsetting states. With the evaluation of known friction coefficients and flow curve parameters, K, n, and ε$_0$ according to the Swift approximation were determined and proved by the final shape of the workpiece.

Cet article porte sur la perception qu'ont les individus des changements qui les affectent, et tout particulièrement sur leur identification et leur évaluation. L'étude porte sur 622 personnes distribuées en cinq classes d'âge couvrant la vie adulte. Les résultats montrent qu'au cours de la première moitié de la vie adulte les changements identifiés sont de bons indicateurs des principaux domaines d'activités et de leurs enjeux, mais qu'au cours de la seconde, ils découlent principalement de la fragilité et de la finitude de la nature humaine. Globalement considéré, le changement dans la vie est avant tout perçu comme un fait positif; le rapport entre gains et pertes présente des modalités différentes selon le groupe d'âge, et si les pertes viennent à l'emporter chez les plus âgés, aucun âge n'est épargné par la perte, comme aucun âge n'est privé de gain. This paper deals with the perception that individuals have of the changes that affect them, more precisely with their identification and evaluation. The sample comprised 622 subjects from five age groups covering adult life. The results show that during the first half of adult life, self-reported changes are related to the main domains of activities and their stakes; during the second part, they mainly have to do with the frailty and finitude of human nature. Altogether, change in life is mainly seen as positive. The ratio of gains to losses varies according to the age group, losses overweighting gains among the oldest, but no age is saved from losses, and no age is deprived of gains. Dieser Artikel befasst sich mit der Wahrnehmung Erwachsener ihrer eigenen Veränderungen, insbesondere mit deren Identifizierung und Bewertung. Die Studie basiert auf einer Stichprobe von 622 erwachsenen Personen, verteilt auf fünf Alterklassen. Die Ergebnisse zeigen, dass während der ersten Hälfte des Erwachsenenalters die wahrgenommenen Veränderungen die wichstigsten Tätigkeitsfelder widerspiegeln. In der zweiten Hälfte stehen sie jedoch vor allem im Zusammenhang mit der Anfälligkeit und Endlichkeit des Lebens. Allgemein betrachtet werden die Veränderungen im Lebensverlauf positiv bewertet. Das Verhältnis zwischen Gewinnen und Verlusten hängt von der jeweiligen Altersgruppe ab. Obwohl bei den ältesten die Verluste überwiegen, bleibt keine Altersklasse von Einbussen verschont, sowie auch keine ohne Gewinn dasteht.

The goal was to, using the numerical simulation of an on-line consolidation process, analyze the influence of process parameters on residual stresses in composite part, regarding composite mechanical properties. In this part was performed the analysis of the thermal stress distribution in the composite part during the manufacturing process. A mathematical model was developed and used to calculate the temperature distribution through the wall thickness of the produced composite part. The model was based on knowledge about the thermal influence on a single constituent tube. Under uneven heating and different coefficients of linear thermal expansion of the constituent materials, thermal stresses were induced. For the process-induced thermal stress analysis and their distribution through the composite pipe thickness a mathematical calculation was performed based on previous data about the temperature distribution. Cilj rada je da se na osnovu matematičkog modela procesa namotavanja kompozitnih cevi izvrši numerička simulacija procesa, kako bi se sagledao uticaj procesnih parametara na zaostale napone u kompozitnoj cevi, odnosno na njena mehanička svojstva. U ovom delu je izvršena analiza raspodele unutrašnjih termičkih napona u kompozitnoj cevi u toku njenog formiranja. Da bi se predvidela raspodela temperatura unutar dobijenih kompozitnih cevi razvijen je matematički model na bazi postojećih znanja o uticaju termičkih promena na jednokomponentne cevi. Usled nejednakog zagrevanja i različitih koeficijenata termičkog širenja konstitutivnih materijala kompozitne cevi dolazi do pojave termičkih napona. Radi analize nastalih termičkih napona izvršen je proračun njihove raspodele po debljini dobijene kompozitne cevi na osnovu prethodno dobijenih podataka o temperaturnom profilu.

When considering replacing conventional materials with composite ones, costs are the major concerns. While the cost of raw materials will usually decline as demand goes up, the production costs of composites can be reduced only through the use of low-cost, automated manufacturing technology, while maintaining good quality. For the thermoplastic composites, the newly developed on-line consolidation technique may have the potential to achieve both desired quality and lower production costs. The great number of commercial used composites have a thermosetting polymer matrix, while the most common reinforcement material is glass fibre. Since in the last couple of years the use of thermoplastic instead of thermosetting polymer materials as the composite matrix is rapidly increasing, hence this study will try to assess the possibility of using polyethylene (high and low density) as a thermoplastic composite matrix. In this part theoretical basis of on-line consolidation process will be given as well as the experimental procedure. Odlučujući faktor prilikom zamene konvencionalnih materijala sa kompozitima su troškovi. Dok cena sirovih materijala obično opada sa porastom potražnje, kod kompozita je potrebno smanjiti troškove proizvodnje automatizovanim procesom uz održavanje dobrog kvaliteta. Kod termoplastičnih kompozita, novorazvijena tehnika kontinualnog toplog presovanja ima mogućnosti dostizanja oba željena cilja: dobrog kvaliteta i niske cene proizvodnje. Najveći broj kompozita koji se nalaze u komercijalnoj upotrebi ima polimernu matricu od termoreaktivnih materijala, dok se kao ojačanje najčešće koriste staklena vlakna. Poslednjih godina je počeo nagli razvoj primene termoplastičnih polimernih materijala umesto termoreaktivnih materijala, pa će u ovom radu biti sagledana mogućnost primene termoplastičnih polimera, konkretno polietilena (visoke i niske gustine) kao kompozitne matrice. U ovom delu će ukratko biti prikazane teorijske osnove procesa namotavanja uz kontinualno toplo presovanje i opis eksperimenta.