ANALYSING THE CHARACTERISTICS OF STUDENT-EMPLOYER INTERACTION - THE CASE STUDY FROM CROATIA

The main objective of the paper is to examine a specialized mechanism for encouraging cooperation between entrepreneurs and students in Zagreb, the capital city of Croatia. By using a specialized mechanism, the students could have the opportunity to complete their internships and work on student jobs within their chosen fields, which means they will be able to apply their knowledge and skillsets on appropriate tasks. At the same time, perspective employers could assess potential employees more effectively and easily define appropriate tasks for them. We argue that the mechanism is suitable for application on a regional (subnational) level in Croatia, as a dimension of the Regional innovation system (Edquist, 2004). Presence of appropriate institutions as well as the availability of adequate skills aimed at facilitating employment of personnel for appropriate job positions is a prerequisite for the functionalizing of mechanism. Regarding the results of analysis of the interaction between students and employers, we conclude that both groups recognize the importance of the students’ proactive behavior in seeking jobs, internships and apprenticeships

Z similarity measure among Fuzzy sets

U radu se najpre analiziraju postojeće mere povezanosti između fuzzy skupova Postojeće mere definisane su kao mere povezanosti dva fuzzy skupa. Ograničenja koja ove mere imaju su da se one primenjuju za fuzzy skupove čije funkcije pripadnosti su prekidne. Takođe, analizirane su osobine postojećih mera. Uočeno je da najčešće ni osnovne osobine, koje bi ove mere trebalo da zadovoljavaju, nisu ispunjene. Na osnovu postojećih mera, analizirana je i Z A,B - mera povezanosti između dva fuzzy skupa. Ova mera zadovoljava osnovne osobine. U određenim slučajevima ova mera daje neodređeni rezultat oblika ∞/∞. U radu je dato rešenje ovog problema. Ovim rešenjem mera Z A,B, u potpunosti je određena u svakom slučaju, a ograničenja koja su nametnuta u postupku njenog izračunavanja, ne utiču na kvalitet rešenja. Koristeći meru Z A,B definisana je nova mera kojom se može utvrditi povezanost između više fuzzy skupova. Sa uvedenim ograničenjima za meru Z A,B, koja je prilagođena za novu meru povezanosti između više fuzzy skupova, nova mera daje kvalitativno dobre rezultate u svim slučajevima.The existing similarity measures between fuzzy sets have been analyzed at the beginning of the paper. The existing measures have been defined as the similarity measures of the two fuzzy sets. The constraints these measures include are that they are applied for the fuzzy sets whose membership functions are discontinuous. Likewise, the properties of the existing measures have been analyzed. It has been noted that in most frequent cases not even the basic properties these measures should fulfill have been fulfilled. On the basis of the existing measures, the similarity measure Z A,B between two fuzzy sets has been analyzed. This measure fulfills the basic properties. In certain cases this measure gives the indefinite result ∞/∞. The solution to this problem has been presented in this paper. With this solution, the measure Z A,B has been determined to the full in each case, and the constraints do not affect the quality of the solution. The new measure with which we can determine the similarity measure of more fuzzy sets has been defined using the measure Z A,B. With the introduction of the constraints for the new similarity measure among more fuzzy sets the new measure provides good results in all cases

Control function on active tilting train based on an appropriate multibody mechanical system

U radu se razmatra problem optimizacije funkcije upravljanja kontrolera aktivnog sistema naginjanja kod vozova velikih brzina, zasnovan na analizi različitih mehaničkih modela železničkih vozila velikih brzina sa samonaginjanjem. U skladu sa klasičnim mehaničkim modelom vozila formiran je odgovarajući mehanički model u obliku sistema krutih tela predstavljenog u vidu kinematičkih lanaca. Formiran je odgovarajući blok dijagram i funkcija upravljanja aktivnog sistema samonaginjanja vozila sa elektrohidrauličkim aktuatorima, za čiju osnovu je predložen osavremenjeni mehanički model vozila, koji omogućava optimalnu formu diferencijalnih jednačina kretanja vozila u koje je integrisana odgovarajuća upravljačka funkcija. .The present paper deals with the problem of controller function in active system of tilting in high speed railway vehicles, which is based on different mechanical models of railway vehicles. According to the classical mechanical model of the vehicle, an appropriate mechanical multibody system is formed in this paper. In conformity with the basic constructive parameters of the active system of tilting, guidance control function of actuator operating process is formed. Basic mechanical model, in dependence of characteristic constructive parameters, according to the theory of robust robotic control is given in the form of closed kinematics chain with branching. For the concrete model of high speed railway vehicle, differential equations of motion are obtained in the form optimal for control function evaluation and calculation

PASSENGER CAR USAGE FOR COMMUTING TO WORK AS A FUNCTION OF LIMITED STAY AT CAR PARKS

The analysis of the experiences in European cities, following the implementation of different transport policy measures, has led to a conclusion that parking policy measures have the dominant effect on the choice of private car as a mode of transport. This effect is the greatest for the commutes to work, characterized by the longest duration of parking space occupancy. Given the aforementioned experiences in developed European cities, the main aim of the study presented here was the determination of a relationship between limiting the duration of parking space occupancy in the Novi Sad city centre and the transport participants’ decision whether or not to use passenger car to commute to work. Based on the established interdependence between these parameters, we developed a mathematical model for calculating a number of expected car (commuting) journeys that terminate in the city centre as a function of limited duration of parking space occupancy.  </p

Analysis of grease contamination influence on the internal radial clearance of ball bearings by thermographic inspection

One of the most important factors influencing ball bearings service life is its internal radial clearance. However, this parameter is also very complex because it depends on applied radial load and ball bearings dimensions, surface finish, and manufacturing materials. Thermal condition of ball bearings also significantly affects internal radial clearance. Despite many researches performed in order to find out relevant facts about different aspects of ball bearings thermal behaviour, only few of them are dealing with the real working conditions, where high concentration of solid contaminant particles is present. That is why the main goal of research presented in this paper was to establish statistically significant correlation between ball bearings temperatures, their working time, and concentration of contaminant particles in their grease. Because of especially difficult working conditions, the typical conveyor idlers bearings were selected as representative test samples and appropriate solid particles from open pit coal mines were used as artificial contaminants. Applied experimental methodology included thermographic inspection, as well as usage of custom designed test rig for ball bearings service life testing. Finally, by obtained experimental data processing in advanced software, statistically significant mathematical correlation between mentioned bearings characteristics was determined and applied in commonly used internal radial clearance equation. That is the most important contribution of performed research the new equation and methodology for ball bearings internal clearance determination which could be used for eventual improvement of existing bearings service life equations

Control function on active tilting train based on an appropriate multibody mechanical system

U radu se razmatra problem optimizacije funkcije upravljanja kontrolera aktivnog sistema naginjanja kod vozova velikih brzina, zasnovan na analizi različitih mehaničkih modela železničkih vozila velikih brzina sa samonaginjanjem. U skladu sa klasičnim mehaničkim modelom vozila formiran je odgovarajući mehanički model u obliku sistema krutih tela predstavljenog u vidu kinematičkih lanaca. Formiran je odgovarajući blok dijagram i funkcija upravljanja aktivnog sistema samonaginjanja vozila sa elektrohidrauličkim aktuatorima, za čiju osnovu je predložen osavremenjeni mehanički model vozila, koji omogućava optimalnu formu diferencijalnih jednačina kretanja vozila u koje je integrisana odgovarajuća upravljačka funkcija. .The present paper deals with the problem of controller function in active system of tilting in high speed railway vehicles, which is based on different mechanical models of railway vehicles. According to the classical mechanical model of the vehicle, an appropriate mechanical multibody system is formed in this paper. In conformity with the basic constructive parameters of the active system of tilting, guidance control function of actuator operating process is formed. Basic mechanical model, in dependence of characteristic constructive parameters, according to the theory of robust robotic control is given in the form of closed kinematics chain with branching. For the concrete model of high speed railway vehicle, differential equations of motion are obtained in the form optimal for control function evaluation and calculation

A FIXED POINT THEOREM FOR F-CONTRACTION MAPPINGS IN PARTIALLY ORDERED BANACH SPACES

In this paper, we first introduce a new notion of an F-contraction mapping, also we establish a fixed point theorem for such mappings in partially ordered Banach spaces. Moreover, two examples are represented to show the compatibility of our results

The Results on Coincidence and Common Fixed Points for a New Type Multivalued Mappings in b-Metric Spaces

In this paper, we obtain the results of coincidence and common fixed points in b-metric spaces. We work with a new type of multivalued quasi-contractive mapping with nonlinear comparison functions. Our results generalize and improve several recent results. Additionally, we give an application of the obtained results to dynamical systems

Distributed control of manufacturing resources: Security related issues

Paradigma industrije 4.0 diktira visoko efikasnu i fleksibilnu proizvodnju uvođenjem konfigurabilnih proizvodnih sistema i resursa koji odlikuju modularnost, interoperabilnost, skalabilnost i mogućnosti komunikacije. Trenutno se širom sveta istražuju različiti pristupi u nastojanju da se dostigne sledeći nivo proizvodnih tehnologija bez ugrožavanja same proizvodnje. Razmatrani pristupi podrazumevaju implementaciju Ciber Phisical Sistem-a, Interneta stvari i generacije proizvodnih sistema Digital Tvins. Složeni industrijski upravljački sistemi, koji su tradicionalno ožičeni i smatraju se sigurnim, sada postaju distribuirani, povezani na internet, obično se zasnivaju na bežičnoj komunikaciji i širom su otvoreni za sve vrste zlonamjernih podviga s potencijalno fatalnim posledicama. U ovom radu predstavljen je pregled bezbednosnih pitanja koja su ključna za razvoj sigurnije bežične distribucije kontrole proizvodnih resursa, pogodnih za izazove u narednim vremenima.Industry 4.0 paradigm dictates highly efficient and flexible production through introduction of reconfigurable manufacturing systems and resources characterized by modularity, interoperability, scalability and communication capabilities. Various approaches are currently researched worldwide in an effort to achieve the next level of production technologies without compromising the production itself. Considered approaches imply implementation of Cyber Physical Systems, Internet of Things and generation of manufacturing systems Digital Twins. Complex industrial control systems, which were traditionally wired and considered safe, are now becoming distributed, internet-connected, usually based on wireless communication and wide open for all kinds of malicious exploits with potentially fatal consequences. This paper presents a review of security related issues that are crucial in developing safer wireless distributed control of manufacturing resources, ADEPT for challenges in coming times