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Thickness measurement is one of the commonly used control measurements in sheet metal forming. Ultrasonic thickness measurement systems demand access to the material only from one side which makes them very useful for this purpose. Distortion of grain structure of the workpiece influences ultrasonic velocity and in that way directly influences ultrasonic thickness measurement. Three different ultrasonic thickness measurement systems are examined on the same working sample. Two systems are defined by standard EN14127. The third system is not defined by the standard and includes previously measured ultrasonic velocity in specific direction of grain elongation. Statistical analysis shows relations between measurement results obtained by all three systems and highlights the third system as the most accurate one.

In this study the original method has been derived from well known hydraulic bulging test, with a purpose of recording the true stress – strain curves. New method allows more accurate determination of membrane stress in the deforming material. Assumption on the bulk geometry is no longer needed since modification, using sphere as an obstacle, determines the radius of curvature needed in acquisition of membrane stress. Performing modified hydraulic bulging upon just one test specimen yields three points of stress-strain curve. Two different sheet thickness and two different sphere diameters have been researched in attempt to establish whether the assumption of membrane stress can be somewhat neglected. The modified method has proved to be adequate for checking the numerical model, because it enables direct experimental measurement of the true stresses in the material, which cannot be obtained when classical hydraulic bulging test is performed.

Based upon the 3D FEM research into standard spur gear stress field and the determined maximum tooth fillet stress for the meshing phase, the stress analysis at the bottom centres of the loaded and adjacent teeth spaces, was performed. The stresses have been separated for characteristic points of single pair tooth contact: the outer, inner and pitch point. The results of the stress analysis primarily indicate the manner a gear rim thickness effects maximum tooth-root stress position and the possibility of tooth-root stress alternation intensification at the tooth bottom centres i.e. tooth fillets.

Good information about friction force generated in contact between wheel and road significant importance in many active safety systems in modern vehicles (anti-lock brake systems, traction control, vehicle dynamic systems, etc.). For this purpose two different approaches has been presented. First approach is based on modification of extended Kalman filter by augmenting it by integral action (PI Kalman filter), in order to estimate additional model parameter. Second estimation scheme is based on RBF neural network. The neural network is added to the estimator to compensate the effects of the friction model uncertainties to the estimation quality. An adaptation law for the neural network parameters is derived using Lyapunov stability analysis. Quality of the estimation for both of estimators is examined through simulations using one wheel friction model.

Model Predictive Control (MPC) is conceptually very attractive control method, since it can be applied for controlling a broad classs of systems, such as linear, constrained linear, piece-wise affine (PWA) and hybrid systems. All constraints on system states, inputs and outputs can be met, and on the other hand one gets optimal behavior according to certain mathematical criterion and a stability guarantee for the closed loop system. As an example of MPC application, in this paper we use MPC on an electronic throttle, highly nonlinear process from the automotive industry that can be approximated as a PWA system.

The objective of the entrepreneurial sector regeneration can be, and is, production for export. To export onto the internal European Union market, product's compatibility with the appropriate EU regulations on product safety must be proven. Products made according to the EU regulations are the driving engine of European integrations. Federation B&H economy is comprised mainly of small and medium enterprises (SME). Successful SMEs form clusters by networking, and accomplish the following objectives: creation of added value, improving their competitiveness and innovative power. Clusters are a path to transforming a small economy into a "large" one. Only successful and powerful economic subjects can find partners in the European regional system, and assure sustainable development.

The application of CAD/CAM techniques has significantly contributed to development of new tools, and application of new technologies in design and production of orthoses and prostheses. This paper gives an short overview obout CAD/CAM system for design and manufacturing of insoles. It presents biomechanical characteristics of the foot which directly implies the features of the future insole. Because of the unity of each foot, the principle of universality, i.e. confectional production of insoles, does not give the expected results. Therefore, the advantage is given to production of insoles according to the clinical and pedobarographic finding of the individual. It also includes the necessity of measurement of static and dynamic stresses on the foot. The paper presents the developed CAD/CAM system, enabling efficient interfacing of all production phases. The system is developed by applying Open GL, Visual C++ and consists of five modules: module for foot scanning and processing of foot images, module for receveing and manipulating of input data, module for creating, modification and final adjustments of the insole, postprocessor module, and database module.

The paper shows a connection between a quality subsystems and a product design system, as well as reflection of the mentioned systems on the menagement costs. The importance of quality in the product development phase is analysed, and especially the problem of developing a new product for high quality is described.

Product recyclability determines recycling costs of end-of-life products. Easy of dessasembly has very important influance on ability for recycling of product. The main area of the research has been to establish a set of guidelines that could be used by designers to ensure that products are designed to meet the requirements for disassembly and recycling. This paper illustrates some of those guidelines and design examples.

The process of transition is characterized by structural changes throughout the economy. The changing economic structure is reflected in the structure of labour market and employment. If we presume the employment structure of the EU countries as a long-term target of the transition, than it is required a comparative analysis of the Croatian labour market among the EU countries and the transition economies of Central and Eastern Europe. The analysis of the labour market is derived from the analysis of the economy and its development. Disparity between Croatia and the EU countries is significant, therefore, Croatia will be compared with EU-15 average and less developed EU countries: Greece, Ireland, Portugal and Spain. Among the transitional economies Croatia will be compared with the most developed: Czech Republic, Hungary, Slovak Republic and Poland. Economic transformation into a market economy accompanied by a series of shocks and the most evident shock for the labour market is the shock of high unemployment. The high unemployment rate is a result of the overall decrease in the demand for labour. The economic structure of unemployment shows that in the Republic of Croatia it is mainly a question of cyclical unemployment, and it is expected to be reduced with the economic upswing.

Industrial robot and laser technique in an interaction are taking key role in almost all fields of techniques. To achieve high performance of manufacturing system ; laser ; robot ; , advantages of laser (high welding or cutting velocity, low heat input, narrow heat affected zone) and robot (high flexibility, low capital costs) should be combined together. The laser- robot manufacturing system for 3D cutting or welding of steel or aluminum plates is most often applied in production of automotive bodies. Several possibilities of linking robot and laser into a complex manufacturing system are presented. Components of laser processing system are discussed. Possibility of combining CO2 and NdYAG laser with robot, and auxiliary devices required for producing the high quality joints at 3D processing are analysed.

In this paper two very important multivariante statistical methods are presented, in one hand discriminant analysis as representative of dependent and in other hand factor analysis as representative of independent methods. The basic aims and the basic mathematical and geometrical concepts for both methods are pointed out. Besides, very briefly are presented two examples of problems from technical practice on which these methods could be favorable applied. For discriminant analysis the problem from production management field, and for factor analysis the problem condition based maintenance field are presented.

In HP fuel pumps, inner surface grinding quality influence is essential for its exploitation characteristics. Monitored roughness is defined by two roughness parameters: maximum uneven spot heights and average arithmetical profile`s deviation from the middle line. Besides influence on exploitation characteristic, quality of ground surface also has influence on dynamic strength of the part, especially monitored in recess part, where it may create strain concentration. This is why a correlation between uneven spot`s maximum height (Rmax) and middle arithmetical profile deviation (Ra) must be known. This paper`s task is to investigate correlation Rmax and Ra for inner grinding of different materials, from which a rectilinear correlation of Rmax and Ra with a strong correlation connection is made. By using different materials, it is proven that material type does not influence this correlation.

The field-related explorations are often concentrated on particular planning elements such as assembly sequence or process simulation, sometimes neglecting the urge of integral and more general approach, which involves still uncovered and computer non-implemented aspects of the process planning. The paper presents the possibility of assembly process representation and modeling using generic structures. The issue is considered on the basis of its combinatorial complexity. In contrary to usual approaches, an assembly plan is not seen as an assembly sequence, but as a sequence of operations. An example will demonstrate that despite the use of only few constraints and formalisms (a quite small planning content considered) leads to the threat of combinatorial explosion and too general and abstracts solutions, proposed approach offers potentials for full covering (enumeration) of the problem space.

Od uporeabe u vojnim pitanjima logistika se razvila u sveprisutnu disciplinu koja bitno doprinosi svekolikom društvenom i tehničko-tehnološkom razvitku. Logistika se pojavljuje na mikro, mezo i makrorazinama. U nizu sastojaka podudara se s organizacijskim znanostima, vrlo često je sinonim za fizičku distribuciju i transport. U najnovije vrijeme sve se više globalizira, što je uvjetovano brzim razvitkom računarsko-informacijske i komunikacijske tehnologije, međunarodnoga korporativnog kapitalizma i prometa. Logistička podrška osobito u prometu i prijevozu sve je važniji činitelj kompetitivnosti na tržištu.

Mould development for injection moulding of polymers is very complex process. The main task of mould designer and mould maker is to produce an optimal mould for certain moulded part. Therefore, mould development can be divided into a few basic phases. One of these phases consists of certain number of mould calculations. Mould calculations can be performed analytically, but because of very fast computers and computer programs development, simulation (numerical) methods becomes more important. Thus, it is possible to carry out with simulation methods mould elements dimensioning, but also to simulate mould cavity filling with polymer melt. With correct simulation it is possible even in this early phase of mould development to avoid faults in mould design, which later can cause many difficulties to mould makers and thus unnecessary make higher the costs of mould manufacturing. This paper shows few examples of simulation in mould development for injection moulding of polymers.

Die Anwendung des Konzepts des Prozeßmanagements und in dessen Rahmen auch des Konzepts des Total Quality Management (TQM) ist in den gegenwärtigen Bedingungen sowohl in der Unternehmen entwickelter Marktwirtschaften als auch in den Unternehmen der Transitionsländer, bzw. der Republik Kroatien, unentbehrlich. Um das Konzept des Prozeßmanagements verstehen zu können, ist es vorerst nootwendig, da damit verbundenen Begriffe zu analysieren: Restrukturierung, ganzheitliche Prozeßgestltung, Revitaliesierung, TQM. Um jedoch kroatische Unternehmen zu ermöglichen, ihre eigene Strategie auszusuchen, müssen ihre Führungskräfte des Gesamtkonzept des Prozeßmanagements verstehen.

The paper deals with the analysis of medium speed diesel engines with a controller, which is a complex system. The System Dynamics Computer Simulation Modelling is one of the most suitable and effective ways of dynamic modelling of complex non-linear, natural, technical and organisation systems. In analysing, system dynamics and simulation models are used as follows: ˇ System dynamics mathematical model ˇ System dynamics structural model ˇ System dynamics computer simulation model Authors suggest using the represented models in engine construction designing, in University education process and diagnosing.

Rad tretira pitanje mjesta i uloge računovodstvenog sustava u poslovnom sustavu poduzeća. Ukazuje na posebno značenje računovodstva i poslova koje ono obavlja (obrada dokumentacije, planiranje i kontrola poslovnog procesa). Naročita je pozornost posvećena informacijama koje računovodstvo pruža a koje su osnova za odlučivanje ne samo menedžmenta već i potencijalnih investitora, poslovnih partnera, države i drugih zainteresiranih subjekata. Računovodstvo je potrebito stalno usavršavati i osuvremenjivati kako bi moglo odgovoriti svim zahtijevima suvremenog, tržišno orijentiranog gospodarstva.

Prikaz normative o upravljanju kakvoćom i osiguravanju kakvoće započinje ukazivanjem na značaj ovog područja i važnosti pravilnog pristupa normativi. Nakon toga daje se u kratkim crtama razvoj normative o kakvoći od prvih izdanja američkih vojnih normi do najnovijih izdanja normi niza ISO 9000. ISO norme o upravljanju kakvoćom i osiguravanju kakvoće podijeljene su prema tematici i numeraciji. Ista podjela je zadržana kod prikaza hrvatskih normi o upravljanju kakvoćom HRN EN ISO 8402:1996, HRN EN ISO 9000-1:1996, HRN ISO 9000-2:1996, HRN EN ISO 9001:1996. i HRN ISO 10012-1:1996. Na kraju se navode norme najavljene za objavljivanje u Hrvatskoj među kojima je i norma HRN EN 45020 o terminima i izrazima iz područja normizacije. Zaključeno je da raspoloživa opsežna normativa o upravljanju kakvoćom na engleskom jeziku, kao i prva izdanja hrvatskih normi o upravljanju kakvoćom, dosad objavljeni radovi i stečena iskustva predstavljaju solidnu osnovu za usvajanje i iskorištavanje tih normi u cilju sveopćeg napretka.

In the paper the utilization of orgnic waste is briefly described, for investigating a number of parameters by which a group of machines for utilizing the organic waste is defined. These parameters are needed in developing and constructing the macines for smashing biomass. taking into consideration all know input-outout parameters,a total function deveeloping into partial ones is defined. The partial functions define partial tasks, solvations of which all the technical functions of a particular smashing machine are realized. By applaying the method of morphological matrix the suitableconstruction solutions are found.

In the field of structural engineering in past time design philosophy was based on the analytical procedure. In present time according to the high speed computers, numerical methods become powerful tool in any structural analysis. Because of the fact that the most engineering systems operate under multiaxial stress conditions as well as under special environment conditions, the prediction of their behaviour under such conditions are of importance. Using elasto-viscoplastic models, overlay method based on the finite element procedure provides the numerical modelling of the viscoplastic material response. This general method is proposed in the presented paper and for its justification some examples are presented.

Using explosive as a source of energy in the processes of processing metals is possible in volume shaping process as well as in other processes of metal processing, e.g. making holes, riveting, calibration, surface hardening, plating, etc. In our case, a 200-mm base of Č 4580 was being drawn by an explosion and the structure of the material was being examined. Detonation velocity of the explosive was 2994 m/s and 6105 m/s. The used explosive was Vitezit 20, and medium for transmission of energy was water. The mentioned steel, before it was drawn had austenitic structure and it belogs to the group of non-magnetic metals, it has unhardenability, it is difficult to process by cutting, but it is good to be drawn.