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- СтавкаDETERMINATION OF LOAD SPECTRUM OF BUCKET WHEEL EXCAVATOR SRS 1300 IN COAL STRIP MINE DRMNO(University of Zagreb, Croatia, 2013) Milčić, Dragan S.; Miladinović, Slobodan M.; Mijajlović, Miroslav M.; Marković, Biljana S.Toothed gear power transmissions are complex mechanical systems and their design is a very challenging engineering task that requires the application of common calculation procedures and contemporary designing methods. Operating conditions of the gear power transmission are important for the design process from the aspect of overload prediction and they are defined within the design process by the operating condition factor KA, which has a wide range of values (1 to 2.5), prescribing various operating situations. However, a good design of the toothed gear power transmission can be achieved if operating conditions are simulated and as such implemented in the calculation/design procedure. Such improvement in the design process can be done with the use of defined load spectra that accurately describe realistic operating conditions. The paper presents the results of tensiometric measurements of torque at the output shaft of the working wheel gearbox of the bucket wheel excavator SRs 1300 TAKRAF in the coal strip mine Drmno, and gives a definition of appropriate load spectra based on these tensiometric measurements. The load spectra are defined by applying the full cycle discretization method and as such afterwards used for the calculations/design of the working wheel of the bucket wheel excavator (gears, shafts, shaft keys etc.).
- СтавкаDesign for Reliability Based Methodology for Automotive Gearbox Load Capacity Identification(Assoc. of Mechanical Eng. and Technicians of Slovenia, 2013) Ognjanovic, Milosav; Milutinovic, MiroslavRobust and Axiomatic design, a property-based approach in design, is applied and integrated into a new methodology for developing Functional Requirements (FR) or Design Parameters (DP). The reliability of the design structure and the elementary reliability of the design components are used as a functional requirement of the automotive gearbox, in relation to the service life and operation conditions, and also as a design constraint in analytical relationships. For this purpose, elementary reliability and allowable stress are defined in a specific way. The automotive gearbox, operating under varying and random operation conditions, is used as a case study. The same design structure has to operate under different operation conditions. In these circumstances, the carrying capacity as a functional requirement is related to the operation conditions and operation regime. The model presented in this paper, as well as a computer program, enable identification of this carrying capacity. This paper discusses an interdisciplinary and multi-methodological integrated approach to the presented task. Experimental data regarding the failure probability of gearbox components and the probability of operation conditions processing, the decomposition of gearbox structure, and the elementary reliability treatment as a component of design property are only some of the methods applied.
- СтавкаModelling and Enhancement of Organizational Resilience Potential in Process Industry SMEs(MDPI, 2015) Arsovski, Slavko; Putnik, Goran; Arsovski, Zora; Tadic, Danijela; Aleksic, Aleksandar; Djordjevic, Aleksandar; Moljevic, SlavisaThe business environment is rapidly changing and puts pressure on enterprises to find effective ways to survive and develop. Since it is almost impossible to identify the multitude of complex conditions and business risks, an organization has to build its resilience in order to be able to overcome issues and achieve long term sustainability. This paper contributes by establishing a two-step model for assessment and enhancement of organizational resilience potential oriented towards Small and Medium Enterprises (SMEs) in the process industry. Using a dynamic modelling technique and statistical tools, a sample of 120 SMEs in Serbia has been developed as a testing base, and one randomly selected enterprise was used for model testing and verification. Uncertainties regarding the relative importance of organizational resilience potential factors (ORPFs) and their value at each level of business are described by pre-defined linguistic expressions. The calculation of the relative importance of ORPFs for each business level is stated as a fuzzy group decision making problem. First, the weighted ORPFs’ values and resilience potential at each business level are determined. In the second step, near optimal enhancement of ORPFs’ values is achieved by applying a genetic algorithm (GA).
- СтавкаFuzzy Approach in Ranking of Banks according to Financial Performances(Hindawi, 2016) Jakšić, Milena; Moljević, Slaviša; Aleksić, Aleksandar; Misita, Mirjana; Arsovski, Slavko; Tadić, Danijela; Mimović, PredragEvaluating bank performance on a yearly basis and making comparison among banks in certain time intervals provide an insight into general financial state of banks and their relative position with respect to the environment (creditors, investors, and stakeholders).The aim of this study is to propose a new fuzzy multicriteria model to evaluate banks respecting relative importance of financial performances and their values. The relative importance of each pair of financial performance groups is assessed linguistic expressions which are modeled by triangular fuzzy numbers. Fuzzy Analytic Hierarchical Process (FAHP) is applied to determine relative weights of the financial performances. In order to rank the treated banks, new model based on Fuzzy Technique for Order Performance by Similarity to Ideal Solution (FTOPSIS) is deployed. The proposed model is illustrated by an example giving real life data from 12 banks having 80% share of the Serbian market. In order to verify the proposed FTOPSIS different measures of separation are used. The presented solution enables the ranking of banks, gives an insight of bank’s state to stakeholders, and provides base for successful improvement in a field of strategy quality in bank business.
- СтавкаINFLUENCE OF QUALITY INFRASTRUCTURE ON REGIONAL DEVELOPMENT(University of Montenegro, 2016) Moljevic, SlavisaQuality infrastructure is developed on state level and covers standardization, accreditation, metrology and certification. It is a “hard” part of quality infrastructure. On the regional level there are “soft” factors such as quality level in organizations, education and training level, state support and so on. The key role of quality infrastructure is to be a basis for all quality improvement actions on lower i.e. organizational levels. It is also a basis for regional development. The influence of quality infrastructure on regional development has not been investigated enough, especially in transition states. That serves as motivation to the authors trying to define an integrative model of quality infrastructure and regional development. This model is partially verified in Bosnia and Hercegovina, being an example of transition economy. A part of the research has been presented in the paper