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This paper presents a synchronic and diachronic computer corpus of Makarska littoral dialects. This corpus was created as part of the project to explore the ikavian neoštokavian dialects of the narrow coastal area in Croatian region of Dalmatia around the town of Makarska. The dialectological characteristics of the dialects studied are briefly presented first, followed by presentation of the digital system. The system is logically organized in first part as a corpus of literary texts created from 1729 to 1803 and digitally processed, and in the second part from the materials collected through dialectological questionnaires prepared and methodologically adapted as part of the creation of the Croatian Linguistic Atlas. Methods of collecting linguistic data, method of input into the digital form and methods and possibilities of data processing will be explained. Based on the input and search strategies within the system, the examples will prove the origin of the dialects of the Makarska littoral to be that of the ikavian neoštokavian dialect described in the dialectological literature. This computer-based principle of work is a novelty in Croatian dialectology which has not been digitally processed so far and offers a basis for future dialectological research. This platform can be used in order to shorten the time of data processing and to analyse them more systematically and more efficiently. So far, there has been no such digital repository for any Croatian speech. This project represents a thorough synchronic and diachronic study of one rounded language area.

Tema ovoga završnoga rada je prikaz, osvrt i kritika naturalističke pozicije P. Kropotkina. Kroz ovaj rad naglašeno je koji su motivi bili za izradu Kropotkinova interdisciplinarnog rada te je objašnjeno kako je ono odgovaralo duhu vremena doba u kojem je nastalo. Osvrtom i kritikom njegove teorije, pokazano je koji su njeni mogući nedostatci u današnjim okvirima, no i jednako tako koliko je takav rad bio prijeko potreban kao posljednje njegovo djelo s kojim je trebao okruniti svoje stvaralašvo. Kroz interpretaciju njegove teorije, korišteni su njegovi tekstovi i naglašeno je kako su argumenti za dokazivanje njegove teorije tekli te kako se time teorija s njenom formom i sadržajem gradila.

U ovoj disertaciji istražena je klasa izravno pogonjenih hidrauličkih sustava upravljanih dvjema pumpama. Sustav je analiziran s aspekta regulacije položaja, energetske učinkovitosti te interneta stvari. Predložen je nelinearni dinamički model sustava, gdje su glavne nelinearnosti trenje u cilindru te protoci kroz proporcionalni ventil. Za regulaciju sustava predložene su četiri različite metode. Prve dvije metode odnose se na linearne regulatore, a to su ISA PID i LQR-I regulator. Iz nelinearne teorije upravljanja odabran je SMC regulator i metoda povratnog koraka. Za sve predložene upravljačke metode dobiveni su simulacijski rezultati za dvije sinusne pobude i jednu skokovitu. Dobiveni simulacijski rezultati usporedeni su sa simulacijskim rezultatima proporcionalnog elektrohidrauličkog sustava te eksperimentalnim rezultatima za oba sustava. Iz eksperimentalnih rezultata, koji su dobiveni za različita opterečenja, izračunato je šest parametara pomoču kojih se usporedivala statička i dinamička točnost sustava. Iz odziva sustava na sinusne pobude izračunate su pogreške u fazi i amplitudi te kumulativna pogreška sustava, dok je za skokovitu pobudu izračunato vrijeme porasta i vrijeme smirivanja odziva te kumulativna pogre_ska sustava. Pomoću navedenih parametara komentirana je statička i dinamička točnost sustava u odnosu na različite regulatore i klasični elektrohidraulički sustav. Energetska učinkovitost sustava izračunata je za različita opterečenja sustava i sve predložene regulatore. Dan je primjer seta mjerenih podataka iz kojih je izračunata energetska učinkovitost sustava kao omjer izlazne i ulazne energije sustava. Dobiveni rezultati međusobno su usporedeni za pojedine regulatore i sustave te su pokazali da je DDH sustav energetski učinkovitiji od klasičnog elektrohidrauličkog sustava. Sa stanovišta IoT-a predloženo je rješenje za udaljeni nadzor i upravljanje sustavom. Razvijen je model baze podataka i web aplikacija te su istraženi mrežni industrijski protokoli. Na kraju, dan je zaključak ovog rada te su predložene smjernice za daljnja istraživanja. In this thesis, comprehensive investigation of a class of direct-driven hydraulic (DDH) systems controlled by two pumps is carried out. The DDH system is investigated from the standpoints of control theory, energy efficiency, and the Internet of Things (IoT). A nonlinear dynamical model of the system is proposed, wherein the main nonlinearities in the proposed model are friction inside the cylinder and ow through the proportional valve. Four different methods have been proposed for solving of fixed and variable setpoint (dynamic trajectory) tracking problems. The first two methods are chosen from the linear control theory, and they are the ISA PID and LQR-I controllers. The SMC controller and backstepping control were chosen from the nonlinear control theory. Simulation results were obtained for the step and dual sine wave reference trajectory for all proposed control methods. Simulation results were compared with ones obtained for proportional electrohydraulic systems, and with experimental results for both systems. Six parameters were calculated from obtained experimental results for different cylinder payloads. Based on these six parameters, the static and dynamic accuracy of the system is evaluated and compared. From the results obtained for the sine wave reference trajectory, phase, amplitude, and cumulative control system error were calculated. The rise and settling time together with cumulative system error were calculated from system response to stepwise reference (setpoint) change. With given parameters, steady-state and dynamical accuracy of the system is evaluated for different control methods and compared to the classical electrohydraulic system. The energy efficiency of the proposed system was calculated for different cylinder payloads and proposed control methods. Energy efficiency has been calculated as the ratio of the output and input system energy based on a measured data set. The obtained results for proposed control methods are mutually compared for DDH and classical hydraulic systems. Results showed that the DDH system's energy efficiency is higher in comparison to the classical electrohydraulic system. From the aspect of IoT, a solution for remote system monitoring and control has been proposed. Web application and database model were developed while network-specific industry protocols have been investigated. Finally, the main contributions of this thesis have been summarized in the conclusion section, which has also given guidelines for further research. This thesis is organized in eight chapters, whose contents are outlined below. Chapter 1: Introduction. In this chapter, a detailed literature review on the topic of this thesis is presented. Motivation for this research is given alongside an overview of the previous work. Based on the detailed literature review, hypotheses and scientific contributions are defined. The outline of the thesis also provided herein. Chapter 2: Experimental setup. This chapter describes the experimental setup used to carry out all the tests presented in this thesis. Hydraulic schematics for proportional and DDH system are also shown. A detailed description of all used components is given along with their technical specifications. Chapter 3: Mathematical modeling. The nonlinear mathematical model of the system is derived in this chapter. First, the dynamical model of the hydraulic cylinder is given, incorporating the nonlinear LuGre friction model. Proportional valve dynamics are modeled as the second-order lag term while the flows through the valve are represented by a nonlinear static function normalized over the maximum range of the control spool movement. A proportional term with volumetric efficiency is used for describing the dynamical behavior of the gear pump. Finally, state-space models of the DDH and classical hydraulic system are given as fifth-order and seventh-order lag terms respectively. Chapter 4: Classical control methods. From the linear control theory, two control methods are chosen for solving of fixed and variable setpoint (dynamic trajectory) tracking problems. The first control method is widely used the ISA PID controller. The controller parameters are obtained with the Ziegler-Nichols method. Simulation results are given for the case of a fully loaded cylinder and comparison has been carried out between the classical system and DDH system through experimental results. For different proportional-integral-derivative (PID) controller structures experimental results are given and mutual comparison between individual PID controller types has been performed. Linear quadratic regulator (LQR) type state controller with integral action (LQR-I) is chosen as the alternative linear control method, with parameters for the proposed control method obtained from a linearized dynamic process model. Obtained experimental results indicated superior control performance (i.e. faster response and smaller control error) compared to the PID controller. Chapter 5: Nonlinear control methods. The sliding mode controller (SMC) and backstepping state-space controller are selected from the nonlinear control system methods in order to further improve set point accuracy and trajectory tracking ability. For both controllers, simulations are carried out and their results compared to those obtained for the classical system, as well as with experimental results for the fully loaded cylinder. In particular, the obtained experimental results show excellent response and tracking capabilities for sine wave reference input. For the case of step reference input signal, both controllers showed roughly the same transient dynamics and obtained similar results as ISA PID and LQR-I controllers. Chapter 6: Energy efficiency. In this chapter, the energy efficiency of the proposed system is investigated. The equations used for calculating the system power and energy are defined. For the cylinder velocity estimation, an algebraic approach is used to determine signal time-derivatives of arbitrary order. An example set of measured data from which energy efficiency is calculated is given for both the DDH and classical hydraulic system. Thus obtained results are mutually compared for both systems and different control methods used in this thesis. Finally, some general conclusion on energy efficiency have been given. Chapter 7: Remote system control and monitoring. An Internet of Things (IoT) solution for remote system control and monitoring is presented in this chapter. Firstly, a schematic representation of the proposed setup is given. Connections between programmable logic controller (PLC), human-machine interface (HMI), camera, web server and, user are defined and explained. A detailed literature review on industrial network protocols is also given herein. Modbus TCP protocol is chosen, as the most suitable protocol for communication between PLC and web server. A suitable database model is designed for continuous data logging and system overall monitoring, with the user administration database model is adopted from the Web2py framework. The developed web application is user-friendly and easy to use. It provides for sending the information to the PLC and monitoring of all relevant data in real-time, with easy integration of new systems being possible through the system administration page. Chapter 8: Conclusion. In this chapter main contributions of the dissertation have been listed, and all hypotheses are confirmed. Several recommendations are given for future research.

In this paper, a new concept of the fuzzy logic controller is presented. The proposed concept is called fuzzy ontology controller and it's based on an ontology description of the Fuzzy Logic Controller (FLC). In this concept, the SPARQL query sent to the ontology replaced the fuzzification process, fuzzy interface, and rules of the fuzzy controller while defuzzification is done on an obtained response. Fuzzy ontology is designed with Prot'{;e};g'{;e}; and hosted in the Virtuoso database on a remote server. Simulation results obtained with the proposed fuzzy ontology controller are compared to ones obtained with the classical fuzzy logic controller. Both controllers obtained the same simulation results due to the same membership function and defuzzification process. The results showed that this concept can be used as a part of some IoT solution within the vision of Industry 4.0. Also, results confirmed that the ontology-based controller works properly and gives the same output as FLC. The experiment is carried out on a heat exchange process controlled with a PLC. Modbus TCP protocol is used for communication between the server PC and a PLC. Experimental results show that only slow processes are controllable for now due to slow communication between PLC and server and the time needed for execution of SPARQL queries.

Increasing demands in terms of reducing the cost of running forestry machines along with the regulatory pressures for lower exhaust emissions encourages the usage of hybrid powertrains in field applications. Hybrid power-trains consist of two or more different energy sources, which leads to many open questions in terms of energy management control, which have significant influence on the power-train, efficiency, fuel consumption and consequently on the operating cost and emissions of greenhouse gasses. Therefore, this paper proposes the optimal energy management control strategy intended to be used in hybridized articulated forestry tractor, also known as skidder. The proposed control strategy is verified on the previously developed skidder model by a comprehensive simulations over realistically recorded field data. The simulation results are used to gain insights about the possible advantages of proposed optimal control strategy in terms of feasible reduction of fuel consumption and related CO2 emissions.

By using built-in or cartridge valves, it is possible to realize cheaper hydraulic systems, which need less space, have a short switching time and less fluid leakage, less time for assembly and installation, and give a better appearance of the hydraulic system, because they are usually installed in an aluminium block. The paper presents a laboratory setup of a hydraulic servo system using cartridge 2/2 valves to achieve precise positioning of the hydraulic cylinder, with the aim of clearly demonstrating the application of these valves in industrial plants, as well as their use in various mobile systems. The article describes the implementation of a control algorithm for the realization of manual and automatic mode of operation of the system and several ways to realize the precise movement of the hydraulic cylinder and simulation of the actuator load.

Forestry vehicles have been increasingly equipped with hybrid electric power-trains in order to provide significant gains in fuel economy, and also to facilitate reductions in greenhouse gases emissions. Due to the fact that hybrid power-trains consist of two or more different energy sources, many questions in terms of power-train components sizing and energy management control are opened, and all of them have influence on the power-train purchase cost and operating efficiency. Therefore, this paper propose an combined optimization approach of powertrain components size along with energy management rules. The hybrid skidder powertrain components are optimized by parametric optimization algorithm with the aim to minimize their size while maintain comparable traction characteristics as conventional forestry vehicle. Optimal control rules are also optimized by recently introduced cascade optimization algorithm with the aim to reduce powertrain fuel consumption. The obtained optimization results are verified by a comprehensive computer simulations, and are also used to gain insights about the possible advantages of optimized powertrain in terms of fuel consumption reduction and related CO2 emissions. The optimization results are also used to provide recommendations for design of a realistic (online) control strategy.

In this paper, a novel energy-efficient Direct Driven Hydraulic (DDH) drive is made in parallel with a classical valve-controlled proportional electrohydraulic system. In the proposed concept asymmetrical hydraulic cylinder is controlled with two reversible pumps directly connected to a servo motor. Due to direct control of the oil flow, such system provides higher energy efficiency in comparison to a valve-controlled hydraulic system. The experimental setup is designed with the possibility of easy switching between both systems, which enables an exact comparison of the experimental results. Sliding Mode Controller (SMC) is designed for the DDH system and also for the classical proportional electro-hydraulic system. A comparison study of two systems is done based on the experimental results obtained with the SMC while reference results are obtained with a widely used PID controller. Parameters for the PID controller are obtained with the Ziegler-Nichols method. The same parameters are used for both controllers in all test cases. The performance and energy efficiency of the proposed system is evaluated through a step and sine wave reference signal with different payloads varying from 0 to 200 kg with 20 kg increments. Additionally, system performance is evaluated based on six parameters calculated from the system response while energy efficiency is calculated based on input and output powers of the systems.

Nowadays there are increasing demands in terms of reducing the cost of running forestry machines along with the regulatory pressures for lower exhaust emissions to improve the ecological indices and reduction of acoustic noise in order to comply with increasingly more stringent industry ergonomic guidelines. Therefore, the producers of forestry equipment are increasingly interested to make such heavy machinery more efficient, which can already be seen with the emergence of certain hybrid and electric powertrain-based forestry vehicles. However, many tools and accessories used by these heavy vehicles are still powered by hydraulics systems. For example, articulated forestry tractor known as skidder uses hydraulic steering, hydraulic lifting for front pushing plate or rear protection plate, and also uses a hydraulic double-drum winch. Having this in mind, this paper investigates the possible use of direct driven electro-hydraulic system instead of the classical one in order to increase the skidder’s operating efficiency. Both the classical and direct driven electro-hydraulic systems are modeled, simulated and experimentally verified for the purpose of comparative analysis of their efficiency. Experiments are carried out under laboratory conditions and experimental results are obtained both for the unloaded cylinder and different payloads. The obtained simulation results are used to gain insights about the possible advantages of the directly driven electro-hydraulic system.

The paper presents the speed control system design and simulation verification of a petroleum drilling system aimed at effective suppression of drill-string torsional vibrations in legacy drilling drives featuring mature series-wound direct-current motor drive technology. The vibration suppression system is based on the external damping feedback loop using a straightforward low-pass filter-based drill-string torque estimator and a reference correction term in the motor speed target path, with the motor speed feedback control system featuring a proportional-integral controller tuned for stiff disturbance rejection. The control system design is based on the damping optimum criterion, which results in straightforward analytical expressions for controller parameters. The effectiveness of the proposed control strategy is verified by means of comprehensive simulations.

Hybrid powertrain presents a viable solution for reducing fuel consumption achieved by a powertrain electrification while maintaining the independence from the electric grid or a charging station. Due to the fact that skidders belong to the class of forestry machinery which is intended for field use, this operating independence is very important. A simple backward-looking model of a series hybrid powertrain skidder is developed and presented in this paper. The model is then simulated over a number of previously-defined operating missions which include realistic track slopes and variable loads. The results are compared with the results of conventional and parallel hybrid powertrains proposed in previous works. Simulation results show that 17% fuel efficiency improvement is obtainable with the proposed series configuration over the conventional skidder in skid trail driving. Finally, the return of investment period of series hybrid and parallel-hybrid configurations are compared, and their respective advantages and disadvantages are listed and discussed.

Nowadays there are increasing demands in terms of reducing the cost of running forestry machines along with the regulatory pressures for lower exhaust emissions to improve the ecological indices and reduction of acoustic noise in order to better comply with industry ergonomic guidelines. Therefore, the producers of forestry equipment are increasingly interested in electrification of heavy machinery, which can already be seen as appearance of the certain hybrid and electric forestry vehicles. The hybrid power-train apparently offers a favourable solution that can meet the above requirements for the propulsion of articulated forestry tractors, also known as skidders, due to the possibility of using a lower-power diesel engine, along with an additional energy storage system (e.g. battery) and driveline power source (i.e. electric motor). This allows the considered hybrid power-train configuration to operate with higher overall energy efficiency and higher mechanical performance indices over the conventional (diesel engine-based) propulsion system, and notably extended autonomy compared to fully-electrified power-trains. Moreover, hybrid power-train requires a smaller battery with less energy then its purely electric counterpart, which results in lower power-train weight and total installation cost. The precise determination of the energy consumption of different types of forest vehicles working in different operating regimes and under different terrain conditions is necessary to select the proper power-train for a specific application. The future development of electrified forestry vehicles is also a very important research topic in the field of sustainable forestry engineering. Having this in mind, this paper presents a literature review on existing solutions for hybrid forestry vehicle propulsion.

This paper based on M-theory wants to show the correlation of Cartesian product of elements of ordered set with a basic, multi-value logic. Using simple algorithms discovered by M. Sare in the natural laws of electrical networks, it is possible to construct logical tables, i.e. grids, for all logic functions of n variables.

Fluid power networks : proceedings : 19th - 21th March 2018 : 11th International Fluid Power Conference / editor: Hubertus Murrenhoff 11th International Fluid Power Conference, 11. IFK, Aachen, Germany, 19 Mar 2018 - 21 Mar 2018; Aachen : [Mainz], 386-395 (2018)., Published by [Mainz], Aachen

Zbog malog vidnog kuta kamere u odnosu na ljudsko oko došlo se je na ideju da se načini uređaj koji će pomicati kameru na transportnom sredstvu, a bit će upravljan pomacima čovjekove glave (gore-dolje i lijevo-desno). U radu je razrađena ideja te je na kraju i realiziran sam sustav. Sustav se sastoji od dva dijela. Prvi dio zove se sklop za mjerenje kuta zakreta glave i on se sastoji od žiroskopa, kontrolera, bluetooth modula i kacige na koju su smještene sve komponente. Ulaz u sustav je kut zakreta glave, koji se potom obrađuje i šalje bežično na drugi dio sustava. Drugi dio naziva se sklop za pomicanje kamere. On se sastoji od bluetooth modula, kontrolera, dva servo motora i kamere. Ulaz u drugi sustav su podatci pristigli preko bluetooth veze između dva sustava te se pomoću njih moduliraju dva signala koji upravljaju servo motorima i pomiču kameru u željenom smjeru. Due to the small visual angle of a camera in relation to the human eye an idea occurred to make a device that will move the camera on the mobile transport device and it will be controlled by rotating the human head in desired direction. In this paper we elaborated the idea and realization of the system. The whole system consists of two parts. The first part is called an assembly for measuring the head rotation angle. It consists of a gyroscope, controller, Bluetooth module and of a helmet on which all components are placed. The inputs of the system are two angles of head rotation which are then processed and sent wirelessly to the another part of the system. The second part is called an assembly for moving a camera. It consists of Bluetooth module, controller, two servomotors and a camera. Inputs to the second system are data received via Bluetooth connection between the two systems, which are then used for modeling two signals for servo motors that are rotating the camera to the desired direction.

In this paper we describe an online application which connects various Croatian lexicographical sources (the standard dictionary, professional terminology, and encyclopedias) into a new network framework, which solves the problems of the currently available network solutions and offers new features. Although developed for the formation and processing of the professional terminology of technical sciences (primarily engineering), this framework is easily extensible to all other science areas (humanities, medicine, architecture, etc.). From a word formation standpoint, this framework provides an automatic generation of a temporary dictionary of a given text (entered or taken from the web), comparison of and updating a permanent dictionary with a temporary one (detection of neologisms), an automatic display (standard, professional and encyclopedic) of definitions of the words from the main dictionary or external (network) sources of a given text. From the point of view of processing, the framework enables a classic text analysis (frequency, concordances, statistics), converting the collected data (e.g. technical words) to the linked open data (LOD), and storing it into the Virtuoso triplestore repository. On this data, a variety of professional ontologies for viewing and searching can be developed.

U ovom radu proučiti ce se mogućnosti Python-a i web2py-a za obradu i izvlačenje informacija iz teksta. Na početku će biti dan kratki uvod u rad sa bazama podataka u Python-u. Zatim će se pokazati web2py. U tom dijelu pokazuje se veza između modela, kotntrolera i pregleda, te kako su oni međusobno povezani. To će se ilustrirati malim primjerom u web2py-u. U trećem dijelu će se razraditi ideja kako iz teksta izvući tehničke pojmove koji se nalaze u bazama podataka te kako prikazati korisniku na jednostavan način te mu uz to omogućiti interakciju s rezultatima. Za kraj dati će se algoritam koji će biti u mogućnosti izvlačiti informacija iz teksta (subjekt, objekta....) uz pomoć regularnih izraza i gramatičkih oblika riječi. In this paper we examine the possibilities of Python and web2py for processing and extracting information from text. At the beginning of the paper we will give a brief introduction for work with databases in Python. After, we present web2py. This part show relation between the model, controller and view.That will be illustrated with a simple web2py application.The third part will elaborate the idea of extracting technical terms from text which are found in databases and how to display it to the user in a simplest possible way and also allowing him to interact with results. At the end will give the algorithm that will be able to extract information from text (subject, object ....) with the help of regular expressions and grammatical forms of a word.

Cilj ovog rada je projektiranje, izrada i upravljanje nastavne makete rotacijskog zamašnjaka. Realizirana nastavna maketa sastoji se od konstrukcijskih elemenata, upravljačkih komponenti, mjernih komponenti i programske podrške (Matlab / Simulink). U zadatku je najprije bilo potrebno izraditi nastavnu maketu mehaničke konstrukcije zamašnjaka pogonjenog električnim motorom preko zupčanog prijenosnika. Zatim, izvesti matematički model sustava i simulirati njegovo ponašanje u programu Matlab Simulink te ugraditi komponente mjernog i upravljačkog dijela sustava na maketu. Potom, razmotriti moguće načine regulacije sustava, odabrati regulator i izvršiti simulaciju sustava. Naposljetku, bilo je potrebno provjeriti odabrani regulator eksperimentalno na nastavnoj maketi. Sustav je najprije modeliran u programskom alatu SolidWorks, zatim je provjeren matematički model u Matlab Simulinku i nakon što su svi podaci bili zadovoljavajući, krenulo se na izradu makete. Regulacija sustava realizirana je korištenjem PI regulatora. Rezultati eksperimenata dokazuju primjenjivost nastavne makete u ispitivanju utjecaja pojedinih komponenti u mehaničkim sustavima. The purpose of this study was designing, production and control of rotational flywheel. The realized model consists of constructional elements, control components, measuring components and software support. In this work we had to create mechanical construction model of flywheel powered by electrical motor using a gear transmission. Mathematical model and simulation had to be tested in Matlab Simulink and components of measurement and control systems were added to the model. Various system control methods regulations were considered, the controller was chosen and system was simulated. In the end the chosen controller was experimentally tested on the educational setup. The system was modeled in SolidWorks software and the mathematical model was tested in Matlab simulink programme. The model creation was started after all data was satisfactory. The flywheel speed was controlled using PI controller. The results of this experiment proved applicability of this model in testing of impact of components in mechanical system.