Planning of the modern manufacturing systems that would be suitable for the most demanding cutting processes requires analysis of all technical and technological process parameters by applying scientific methods, modeling and optimal conditions of machining process and systems defining. In order to secure the planned functioning of machine tools they need to be sufficiently resistant and stable at all influences which are exposed in the cutting process. Because high number of influence factors to the cutting process, it is very difficulty to determine most influence parameters of the cutting process by analytical model. For this reason it is necessary to apply the experimental measurements and analysis of the results which will be used for creating fudantion for cutting force identification and which is indispensable in the development of new machine tools and improving existing machining systems. Objective of this paper is to find mathematical algorithm of tool holder acceleration aNA = f(σz, v, δ) in function of machined material strength, cutting velocity and depth of cut. Experimental investigation of tool holder acceleration during turning process has done for three different types of steel: 9SMn28, S355JOG3 and C45E.

In this paper we present and elaborate one research example when bauxite was the main target of the investigation. During reprocessing and reinterpretation of the original data from the “Crvene stijene” locality near Jajce in Bosnia and Herzegovina, it was established that bauxite hanging wall and footwall rocks in fact represent an even more valuable mineral resource, as “dimension stone”. The final goal of the research was to optimize the ratio between research and exploration costs and total profit by exploration of all available mineral resources in the area. For that purpose, a new research evaluation method encompassing both bauxite (primary resource) and associated deposits was developed and named the “integrated approach”. Integrated, joint evaluation of bauxite and associated deposits (dimension stone), gives a far greater economic significance to whole area. Finally, with this new method, the ratio between overall profit and cost will be optimized which results in significant increase in profit because all available deposits are considered for exploitation. Also this method can be applied on abandoned mining sites if there is some secondary profitable mineral deposit in the mine area.

Neophodna interdisciplinarna istraživanja u cilju ocuvanja parka odnosno njegovog temeljnog fenomena, pocinju s geodetskom studijom koja treba prikupiti i sistematizirati sve dostupne podatke o digitalnom modelu terena (kopneni dio) i hidrografske podatke (podrucja pod vodom - dubine), te ih spojiti u jedinstveni digitalni model reljefa (DMR) parka prirode "Kopacki rit". Radi se o heterogenim podatcima koji su nastali u razlicitim vremenskim periodima, i najcesce su obuhvacali parcijalne dijelove Parka te su ih izrađivali razliciti izvođaci. Podatci se sastoje od klasicnih topografskih karata i planova, fotogrametrijskih snimaka, djelomicne hidrografske izmjere i podataka zracnog laserskog skeniranja. Svaki od tih setova prostornih podataka u sebi sadrži određene nedostatke s obzirom na prednosti i mane pojedinih tehnologija potrebnih za njihovo prikupljanje. To se prvenstveno odnosi na karakteristike pojedinih setova prostornih podataka po pitanju detaljnosti (razlucivosti) i pokrivenosti (obuhvacenosti) mjernim vrijednostima svih reljefnih oblika. Jednako znacajan je i vremenski cimbenik s obzirom da podatci nisu prikupljani u isto vrijeme (sve od jednom), nego u određenim vremenskim razmacima - epohama. To znaci da je moguce, cak i vrlo izgledno, da je između dvije epohe mjerenja doslo do promjena reljefnih oblika dijelova Parka (sedimentacija i erozija npr.), te da ce podatci mjereni u razlicitim epohama prikazivati razlicite oblike na istim podrucjima. Stoga je potrebno prikupljene podatke sistematizirati, ukloniti uocene pogreske, analizirati te provesti potrebne transformacije i zatim po prvi puta formirati jedinstveni DMR. S obzirom da se radi o zaista velikom podrucju (17.700 ha), izrada novog detaljnog DMR-a za kompletno podrucje Parka zahtijevala bi velika financijska sredstva te je prethodno potrebno izraditi ovaj prvi cjeloviti DMR, koji ce se sastojati od svih dosadasnjih postojecih mjerenja iz razlicitih epoha koje je za sada moguce prikupiti. Ovakav DMR je osnova za provođenje geodetskih i geoloskih istraživanja. Primjer su simulacije plavljenja, simulacije sedimentacije i erozije odnosno izrada matematickih i statistickih modela i varijanti neophodnih za donosenje odluka o rjesenjima i mjerama revitalizacije vodenih eko-sustava i vlažnih stanista poplavnog podrucja. Isto tako ce poslužiti i za pocetne procjene i modele određivanja ukupnih volumena vodenih i kopnenih dijelova Parka prirode "Kopacki rit". Ocekivani rezultat ce biti prvi cjeloviti DMR sa analizom i procjenom potrebne razlucivosti i tocnosti eventualno potrebnog detaljnog DMR-a, za krajnja racunanja i potrebe projektiranja.

The development of technology and the means of labour in the technological process of forest harvesting in FBiH mainly depends on the factors related to the specific manner of forest management. The dominant share of mixed tall forests with natural regeneration, the selective manner of management and rather difficult natural conditions have resulted in the application of the cut-to-length method and to a lesser extent, the tree-length and semi-tree-length methods. On the basis of expert classification of the development phases in forest harvesting, it can be noted that wood assortment production in FBiH is currently partially mechanised. With the aim of defining measures for increasing productivity, lowering the costs and a greater humanisation of work, there has been an analysis of the current state of the means of work in all three phases of forest harvesting. The analysis included the following parameters: number of means in different phases, the type, the average age, ownership and technical planned obsolescence. All the data were collected through a survey which included all stakeholders (cantonal forest companies and private contractors). The results showed a satisfactory state only when chainsaws are concerned, i.e. the rather cheap tools. Other equipment (adapted tractors, skidders, trucks, etc.) has largely reached planned obsolescence. Their old age results in a low level of utilisation, i.e. an insufficient amount of working hours per year which eventually leads to a decrease in productivity and increase in expenses. Based on the data, it can be concluded that it is necessary to begin the process of new mechanisation procurement and the replacement of existing, time-worn and technologically obsolete machines with new ones. At the same time, it is clear that, in the conditions of low availability of investment capital and cheap labour force, this has to be a gradual process. In relation with this, the process should start in the most expensive phase - timber extraction, i.e. the phase in which the economic efficiency is unquestionable.

s of Croatian Periodontology Days 2015 congress Zagreb, Croatia, April 10-11, 2015 Predsjednik • President: