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Efforts to reduce global greenhouse gas (GHG) emissions have significant implications for the maritime sector. Reducing global emissions requires that newly built ships become more energy efficient or that all subcomponents of ship systems improve their individual or overall energy efficiency. As a result, ship electrification, which is considered to be the most viable proposed method to achieve the emissions reduction goal, will place a large burden on the ship electrical system. The projected load will lead to improvements in all aspects of the electrical system (power generation, distribution, and consumption). This paper addresses the optimization of the distribution system, or specifically the important subcomponent, the main switchboard, through previously developed improvements, starting from the definition of the switchboard parameters, through the modification of the busbar configuration area and the implementation of novel sensor technology, to ultimately optimize the design compared to an existing solution.

The laboratory facilities of the faculty play an important role in training future maritime electrical engineers. With the electrification of the marine industry, the importance of understanding electrical laboratory equipment is increasing. Technological advances will expose future maritime electrical engineers to increasingly complex systems, circuits, and topologies. In this paper, the focus is on a widely used component, the self-commutated power converter. The aim of the paper is to familiarize the students with the topology of the converter used in the laboratory exercises. The used converter is built on black-box principle i.e., the students cannot see the discrete components. The schematic that can be seen on the converter itself represents the mains filter and the dU/dt filter on blackbox principle, i.e. the manufacturer does not provide any technical details about the filters. The model of the converter with mains and dU/dt filters is created using Matlab/Simulink Simscape components. To validate the model, the voltage and current waveforms measured on the actual device using an oscilloscope and the original manufacturer's software are compared with the simulated output waveforms.

Optimization of a ship's high voltage (HV) switchboard at the individual switchgear level with the aim of improving the overall energy efficiency is achieved by reducing various influencing factors. The optimized switchgear design still has to meet the conditions regarding thermal, electrical and mechanical stress. Therefore, new designs of AirInsulated Switchgear (AIS) are subjected to various type tests to verify their compliance with the relevant standards before they can be used in an electrical system. In preparation for type testing, various computer- based simulations must be performed to predict the behaviour of the proposed design. These predictions help to keep the overall production cost to a minimum, as various problems that lead to type test failure can be identified in advance. One of the type tests to be fulfilled is the temperature rise test, where the thermal stress of the busbars at rated current is analysed, with rise limits defined according to IEC 62271-1. In this paper, the temperature rise analysis of several selected three-phase busbar systems for use in a newly proposed AIS design using FEM and CFD is presented. In order to save computational time, simplified models are used for the first selection, where the electromagnetic losses of the busbars are used as the source of heating and natural air convection is also considered. The objective of the simulation is to select a busbar configuration that has the lowest temperature rise and electromagnetic losses, which ultimately contributes to the overall energy efficiency of a ship's electrical distribution system.

This paper presents the measurement process of the emissions from marine diesel engines. The emission measurement was carried out by the certified TESTO 350 Maritime exhaust gas analyzer on the Juraj Dalmatinac ferry Caterpillar C32 engines. The gas analyzer records the concentrations of nitrogen oxides (NOx), carbon monoxide (CO), carbon dioxide (CO₂), oxygen (O₂) and sulfur dioxide (SO₂). TESTO 350 emission sampling probe was set at the end of the exhaust pipe. A combustion emission measurement was performed during a Split – Supetar (Brač) trip and backwards with the total duration of 110 min. The emissions are estimated for two trip phases: “maneuvering” and “at sea”.

Air pollution, which has been identified as a global concern, has a significant influence on human health and environment. Human health is affected differently by long and short-term exposure to air pollution causing respiratory and cardiovascular disorders, long-term chronic diseases like cancer and different diseases. Ships emit significant amounts of pollutants into the atmosphere, primarily sulphur (SOX) and nitrogen oxides (NOX), as well as particulate matter (PM). Shipping emissions of sulphur and nitrogen oxides have consistently increased over the last thirty years, despite efforts in lowering emissions from land-based sources. As a result, the purpose of this research is to determine main ship air pollutants, their effects on human health, and proposing measures of prevention.

Additive manufacturing, commonly known as 3D printing, is the technique of creating three-dimensional solid objects from a digital file.There are many potential benefits of 3D printing for the maritime industry such as 3D printing spare components ashore for delivery to ships, and 3D printing spare parts onboard ships. Small replacement parts such as impellers, valves, and pipe fittings can be printed onboard by ships equipped with appropriate 3D printers. This minimizes wait times and allows the rapid and geographically independent supply of replacement parts and components. Since 2017, 3D printed high-load items such as propellers and crane hooks have been authorized by DNV, RINA, Lloyds Register, and ABS meaning that when printed parts are properly built, they are able to meet Class standards. With the permission of major classification organizations and numerous important marine enterprises, 3D printing in the maritime industry can only grow in popularity as it matures. This paper aims to show the principle of work of the 3D printer, possibilities of integration, and application in the maritime sector with the example of 3D printing in the maritime industry.

The training and practice of future marine engineers in the field of marine electrical systems in realistic conditions presents several risks, especially if the training is regarding high voltage electrical systems. In order to minimize the aforementioned risks, the training should be conducted on a simulation model that can adequately simulate the behaviour of the analysed systems so that the quality of the training is not affected. In this paper, the steady-state behaviour of an induction motor fed by a two-level voltage source inverter (2L-VSI) is investigated. Lucas-Nulle devices allow the measurement and recording of a large number of values such as voltage, current, slip, power factor, active power, reactive power, power, voltage and current frequency spectrum, modulation signal. In this work, the objective is to build a simple space vector modulation signal generator using "black box" library components in Simulink and use the measurement to validate the parameters of the inverter and induction motor. The results of the Simulink model on the motor side show good agreement with the measurement result, indicating that the motor parameters are correctly determined.

Usage of renewable energy sources is something that modern shipping tends to, therefore naval shipbuilding shouldn't be excluded from it's implementation. This paper shows an example of possible implementation of „green energy“ on logistic support vessel PT-71, that is a part of Coast Guard of Republic of Croatia. It presents the possibility of installation of renewable energy sources and its economic and ecological effectiveness. The system is made of photovoltaic panels, batteries, solar „all in one “inverter and wiring. Considering the possibilities of positioning the photovoltaic panels on ship's outer free surfaces, it is estimated to install 56 panels of total nominal power 9240 W. The features of all other system elements are fitted to photovoltaic panels. The paper specifies costs of acquiring all system elements, and it also considers the costs of installation and maintenance of the entire renewable energy source. Conclusion shows the advantages of applying this kind of renewable energy system on vessels.

The ISO 9001 standard is the fundamental standard for quality management systems and is used by over one million organizations around the world, regardless of the size and type of activity they are doing. Seafarer training and training institutions must have one of the quality management systems, usually ISO 9001. Due to this, it is of great importance to introduce this standard and to maintain it. Quality is today one of the most important characteristics of successful business, and by implementing the ISO 9001 standard, a high degree of quality of products and services is achieved. The paper describes the standard ISO 9001: 2015, its advantages and disadvantages. An emphasis is put on determining the risks and measures that need to be taken to minimize such risks. The risks are analysed, on few institutions that organizations face, the problems that arise in risk management, and the risks that the company takes with regard to the organization's operations.

U radu je predstavljen koncept električnog katamarana za liniju Split – Zračna luka “Split”. Navedena linija posebno je zanimljiva u ljetnim mjesecima kada može pružiti alternativu cestovnom prometu. Tehnologija također pruža mogućnost transporta bez emisije štetnih plinova. U radu je predočen pojednostavljeni proračun dimenzija katamarana za 152 putnika. Brzina katamaran je određena tako da se jedan prijelaz linije odvije u 30 min, uz poštivanje pravilnika koji određuju brzinu plovila blizu obalnog područja i u luci Split. Na temelju proračuna dimenzija uz poznatu brzinu određena je snaga pogonskog stroja. Za pogonski stroj odabran je asinkroni kavezni elektromotor. Napravljen je simulacijski model porivnog sustava u simulacijskom okružju Simulink, programskog paketa Matlab. Na kraju su prikazani rezultati simulacije, odnosno prikazan je odziv brzine, snaga i energija elektromotornog pogona porivnog sustava.

The recent global economic crisis started in 2008 as a subprime (high-risk) mortgage market crisis in the USA and developed into a large- scale international economic crisis, affecting banking systems, financial institutions, insurance, funds and stock exchange. The crisis was followed by the Great Recession and the Eurozone crisis, impacting both the service and production sectors. The global crisis was a very complex phenomenon, not only with regard to its scope and scale, but also due to the complexity of global economic relationships. International companies and all companies performing on international markets have been affected by the events, directly or indirectly related to the crisis, which have been occurring on their respective markets. After a brief overview of the causes, scope and consequences of the global economic recession, this paper provides an analysis of the effects of the offshore market crisis on the performance of Croatian maritime shipping companies (in this paper that are Atlanska plovidba d.d., Jadroplov d.d., Lošinjska - Holding d.d., Brodospas d.d.).

This book appeared at the right time given the recent emphasis on curriculum reform of the education system in the Republic of Croatia. Its intention is to incorporate technology into the education system together with abundance of significant opportunities and challenges. ICT plays a significant role in education of the digital age, and learning is structured through transformation of various educational technology innovations.This book introduces innovations in the form of quality practices from different parts of educated community in Croatia. This book presents some issues that institutions can take into account in developing their strategies in this fast digital world of education.

Automatizacija se sve više primjenjuje na brodu pa iako je korist velika tu su i zapreke za koje ako posada nije dobro pripremljena može doći do smanjene, a ne poboljšane operativne učinkovitosti, pa čak do velikih dodatnih troškova popravaka i ozbiljnih nesreća. Učinkovita automatizacija ovisi o stručnosti osoblja, što zauzvrat ovisi o edukaciji članova posade. Novi sustavi, navigacijski i oni koji su vezani uz strojarnicu, moraju biti sigurni i pouzdani, posebno oni koji su u potpunosti automatizirani. Elektroničke komponente, kao i računalne tehnologije prolaze kroz dinamičan razvoj i postoje razlozi za povećanu primjenu elektroničke opreme u brodskim sustavima čak i za manje složene zadatke. To zahtijeva znatne napore u obuci posade u cilju praćenja razvoja i primjene nove tehnologije, koji se osobito odnose na časnička zvanja. Primjena digitalnog okruženja za obrazovanje pomoraca je nezaobilazna, što nameće potrebu za nadogradnjom alata za e-učenje, ali isto tako i za razvijanjem novih. U radu su predstavljeni različiti aspekti i mogućnosti primjene digitalnog okruženja za obrazovanje pomoraca.

Povećanju ekonomske djelotvornosti i životnog standarda društva doprinosi obalna plovidba kao dio pomorskog prometa. Nastojanja Europske komisije usmjerena su na oživljavanje obalne plovidbe kao novog, alternativnog i održivog načina prijevoza. Održivi prijevoz podupire gospodarsku aktivnost, ograničava ispuštanje štetnih tvari u mjeri koju okoliš može apsorbirati, minimizira potrošnju neobnovljivih izvora energije do razine održivog iskorištavanja, ponovno koristi i upotrebljuje njihove sastojke. Značajna pažnja se posvećuje poboljšanju Energy Efficiency Design Index-a (EEDI) na koji utječe instalirana snaga broda, brzina kojom se brod kreće i karakteristike tereta koje prevozi. U radu je prikazana pojednostavljena formula za EEDI koja opisno prikazuje koji sve sustavi, odnosno faktori sudjeluju pri izračunu same vrijednosti indeksa. Manja vrijednost indeksa znači veću energetsku efikasnost broda. Također, EEDI je i mjera utjecaja broda na okoliš što se može vidjeti iz same mjerne jedinice indeksa: masa emitiranog ugljičnog dioksida po jedinici prenesene mase tereta i brzine plovila. U radu je analizirano stanje u RH u usporedbi s prvim plovilom s obnovljivim izvorima energije. Analizirana je primjena električnih plovila obzirom na energetsku učinkovitost i primjenu u lukama. Razrađenim mjerama koje potiču inovaciju i nova tehnološka rješenja i strateškim mjerama otvara se prostor ili dio prostora u kojem ćemo moći biti konkurentni i kompetitivni.

There is a wide field of technologies like low- sulphur fuels, internal engine modifications (such as water injection and exhaust gas recirculation), humid air motors, selective catalytic reduction, duel-fuel engines that are contributing to air pollution reduction caused by ships. With growing concern for environmental air pollution, there is also a growing interest for the application of renewable energy technologies on ships. These technologies are not new to the world, but when considering the ship as the place of the installation this raises the question regarding the ship overall design and the impact on fuel consumption and air pollution. In this paper the concepts of wind and solar energy production on ships are presented. The overview of the experimental ships that are harvesting the renewable energy is given in the text. Also, the new concept of wind and solar combined in the form of rigid sail is presented. The concept of medium voltage direct current distribution system application is presented in the paper. Traditional electrical distribution system on ships is low voltage AC system. This concept is very different from renewable energy technology but also provides fuel saving thus providing less air pollutants.

Brod se može smatrati jednom pokretnom elektranom gdje se proizvodnja, razdioba i potrošnja električne energije odvija na jednom mjestu. Kako većinu potrošača električne energije na brodu predstavljaju električni strojevi te je njihovom snagom određena i snaga brodske električne centrale. Razvojem tehnologije brodski elektroenergetski sustavi postaju sve složeniji sve više zahtjeva se postavlja pred posadom od koje se traži sve više znanja, vještina i sve veći broj ovlaštenja. Značajna pažnja se posvećuje poboljšanju Energy Efficiency Design Index (EEDI) na koji utječe instalirana snaga broda, brzina kojom se brod kreće i karakteristike tereta koje prevozi. Primjenom obnovljivih izvora energije doprinosi se povećanju proizvodnje zelene energije i uz razvoj energetske elektronike pruža se mogućnost implementacije srednjenaponske istosmjerne mreže na brodu - MVDC (Medium - Voltage DC). Na brodovima se implementira sustav za skladištenje električne energije. U radu su navedene prednosti istosmjernog sustava za razdiobu električne energije u odnosu na izmjenični sustav koje se ogledaju u smanjenju sveukupne mase električne opreme i smanjenju potrošnje goriva što doprinosi energetskoj učinkovitosti.

This paper deals with improving the curriculum for the Marine Electrical Engineering and Information Technologies Department at the Faculty of Maritime Studies in Split, with a particular focus on the master level. While the BSc level is defined by the STCW 7.03 (lower level) and 7.08 (higher level) requirements, the MSc level structure is largely blurred. So, finding a right niche in the labor market ashore should be the goal of the curriculum improvements. It is important to assist the 3 year program students in finding shorebased jobs by introducing adjustments to the current curriculum. Nowadays, it is not expected that any one will remain aboard for the entire work life. It is more natural to keep developing various skills and, at some point, start working ashore at private or government agencies / services, possibly in the area of inspection, education, logistics, fleet management or other related professions. For electrotechnical officers (ETOs) it is even possible to find work in the fields that are not directly related to marine technologies, but rather to the electrical know-how. A new curriculum for the master level should enable such engagements but also, at the same time, it should avoid parallelism problems with pure electrical engineering studies at similar higher education institutions, e.g. electrical engineering faculties. One of the fields that lack skilled employees is the IT and software industry. When dealing with software requirements, the ability to function in different working and business environments should be an imperative in future traffic applications. These skills will also help in finding jobs in shore-based and IT businesses. The paper presents a workflow of the plans to change the curriculum for the Marine Electrical Engineering and Information Technologies (MEEIT) Department in order to position MEng of MEEIT clearly at the EU labor market.

Elektromotorni pogoni zauzimaju značajni udio u potrošnji proizvedene električne energije na brodovima. U pogonima sa teškim uvjetima rada kao što su brodogradilišta, radni brodovi, cementare, čeličane i slično, zahtjeva se visoki stupanj pouzdanosti, te se klizno kolutni asinkroni motori zadržavaju u upotrebi kao sigurno i pouzdano rješenje. Sigurnosni, tehnološki i ekonomski zahtjevi traže poboljšanje u upravljanju radom motora što je u ovom radu i prikazano primjenom tiristorskih regulatora napona kojima se regulira napon na statoru motora i doprinos se upravljanju uz postojeće upravljanje u rotorskom krugu motora. U radu su opisani razlozi, postupak i rezultati ugradnje uređaja na motorima koji služe za pogon dizanja / spuštanja i otvaranja / zatvaranja grabilice mosne dizalice za rasute terete.

The advantage of a simulation is the level of detail that can be obtained from it. A simulation yields results that are not experimentally measurable with our current level of technology. Most of the time, simulation testing is cheaper and faster than performing multiple tests of the real design. Designing and testing is becoming much easier with development of simulation tools. The pretesting while the model is still under construction can eliminate the different oversights that can be made. Three of the most commonly used types of converters used as motor drives for AC motors in electric propulsion are presented in this paper: cyclo-converters, PWM converters and synchro-converters. Modelling the frequency convertors in simulation software, it is possible to define which converter is suitable for a given power system.

U skladu s STCW konvencijom nastavni program pomorskih studija zahtijeva realne softverske alate za rješavanje inženjerskih problema. Ovi programski alati moraju uzeti u obzir ograničene resurse na brodu. Pomorski inženjeri su skloniji uporabi vizualnih resursa kao što je MS Excel. Excel je proračunska tablica koja omogućava komunikaciju s raznim eksternim aplikacijama te može poboljšati nastavni program pomorskih studija. Zbog izbjegavanja monotonih računanja i ponavljanja istovjetnih radnji kod pomorskih inženjera uočena je potreba za automatizacijom kalkulacija. U tom kontekstu, VBA se pokazao kao dobro rješenje. VBA je programski jezik integriran u MS Excela koji omogućava programiranje funkcija koje nisu standardno uključene u Excel. U ovom radu se ističe uporaba Excel-a i VBA u rješavanju pomorskih inženjerskih problema i prezentirani su slikoviti primjeri. Rješavanjem zadataka pomoću Excela i VBA, studenti i pomorski inženjeri bi imali korist u svom daljnjem radu.

Container terminal logistics has been a prominent field of research and the term Automated Guided Vehicle Systems has become a keyword in publications. This paper is devoted to the modelling and control of automatic guided vehicles (AGVs) assuming that the transportation system configuration is given as well as transportation task. AGVs follow a guide-path while controlled by a computer that assigns route, tasks, velocity, etc. The AGV motion can be described as the set of discrete events and states. Some of these states can be undesirable such as deadlocks and collisions. By applying adequate control policy to avoid such states and block the vehicles motion only in the case of dangerous situation it is able to improve the container terminal's overall logistic efficiency. The Coloured Petri net is used for the process control specification.

Electrical system of ships is autonomous systems. The prime movers including diesel engines, gas/steam turbines, are integral parts of the systems which produce energy for large consumers (for example thrusters, propulsion systems, drilling systems ect.) and "small" consumers (navigation, lights...). The complexity of vessels such as cruise vessels, ice breakers or vessels where much maneuvering is required (frequent change in propulsion load) requires dependable electrical power for operation, integrity of the well and safety - of both the installation and its personnel. Safe, secure and efficient shipping on clean ocean, suggested by International Maritime Organization (IMO), requires the development of appropriate design, operational knowledge and assessment tools for energy efficient design and operation of ships. In this paper we analysed the hybrid renewable energy system. The design of future ship will require the development of new and increasingly sophisticated methods for the modelling and simulation of the complex systems that must be integrated in order to produce the total energy for the ship. Control architecture for power distribution systems has to be hierarchical, distributed and easy to adapt. A complete logistic chain of this control architecture will be modeled by Colored Petri Net (CPN), which connects effective agents for autonomous control of complex distributed systems which agents for the control of power management systems.

Ovaj se rad bavi upravljanjem prometom i optimizacijom rasporeda poslova u sustavu prometa autonomnih vozila (eng. automatic guided vehicle, AGV) na kontejnerskom terminalu. Primjena autonomnih vozila uvelike smanjuju troškove i povećavaju učinkovitost modernih industrijskih postrojenja pa i velikih pomorskih luka. U ovom radu je primjenom Petrijevih mreža prikazan model AGV sustava kontejnerskog terminala i implementirana je strategija upravljanja prometom AGV vozila koji se koriste na kontejnerskom terminalu. Cilj je upravljanja riješiti konflikte, uz izbjegavanje zaglavljenja u sustavu. Nadalje, u radu je primjenom više-objektnog genetskog algoritma određen optimalan raspored poslova AGV- ova. Glavni cilj optimiranja je minimalizirati ukupno vrijeme izvođenja svih poslova, kao i vrijeme čekanja AGV-ova na dizalice, jer se na taj način povećava protočnost cijelog terminala. Sporedni cilj je minimalizirati broj AGV koji su uključeni i održavaju protok u sustavu. Razvijeni algoritam je testiran primjenom računalne simulacije koristeći program MATLAB. U radu su prikazani rezultati simulacije i eksperimenta na stvarnom kontejnerskom terminalu.

New technologies in shipping fundamentally alter the activity of the maritime economy, and changing the world of maintenance and maintenance philosophy. Competition on the global shipping market, great complexity and dynamism of the ship and its environment, require efficient management and effective decision-making. Based on the information about the technology used by maritime companies and data on the impact of technology on business and strategic development of companies in the shipping industry analysis will determine the extent of the technological environment in the strategic development of companies in the shipping industry. The analysis will show the importance of technology for business, the risks that entails, and the connection between technology and strategic development of the company. The aim of this paper is to analyse the impact of technological environment on business strategy of shipping company i.e. to analyze the impact of new technologies on decision-making and business management which is reflected in the overall operations and the development of enterprises. Also, the aim of this paper is to explore, evaluate and define the methods and computational procedures that will improve management strategies for maintenance of ships and manage risk and improve performance information support.

In the Republic of Croatia, over the last fifteen years, nautical tourism has been experiencing a strong expansion. Despite the general recession that prevails on the global market, nautical tourism in Croatia, according to the recent studies, has been recording high annual growth rates. In order to maintain competitive position on the market of the nautical port services which become highly dynamic and demanding, supply of such services should be continuously adapted to the increasing nautical tourists` demands as the main beneficiaries of the nautical port services. In order to enable optimal development of nautical tourism ports as the major accelerators of the nautical tourism prosperity, in this paper the factors that indicate the competitiveness of the nautical tourism ports have been determined and defined. Also, systematic analyses of elements which contribute to the overall competitiveness of the nautical tourism ports have been performed. Number of berths, price of berths, marinas` infrastructure and catering facilities are just some of the evaluated parameters. Such analysis is carried out with a goal dedicated to improvement of the long-term sustainability of the nautical services quality in the Croatian nautical tourism ports.

Computer simulation models represent important field in many aspects of vessel traffic, thus in a vessel collision occurrence aspect as well. Modern technology base and it’s advantage in terms of functionality capabilities, graphics and user interface over some conventional approaches is pointed in this paper through a discrete – event vessel collision simulation model. Vessel collision simulation model is custom – developed using one of modern object oriented programming languages – C#. Special case of vessel collision occurrence in straits where two vessels approach from opposing directions is taken as an example to present this model’s reliability. Results obtained by simulation are within the scope of verified analytical solutions.

Brodski elektroenergetski sustav je znatno jednostavnije analizirati na nekom od simulatora ili odgovarajućim simulacijskim modelima pratiti promjene stanja jer se ne ugrožava pogonsko stanje, nema oštećenja na značajnim dijelovima postrojenja (generator), može se ići do krajnjih granica ispitivanja (kratki spoj , a da se pri tom ne ugrožavaju životi posade i sama postrojenja. Simulacijom je omogućena kvantitativna analiza procesa koji podrazumijeva da se taj proces odvija u vremenu, uključuje slučajne veličine , koristi resurse sustava, veliki broj međusobno povezanih elemenata. Simulirajući određene procese, pokušava se odgovoriti na pitanje što ako je stroj u pogonu pokvaren, što ako poraste potreba za većom potrošnjom goriva i slično. Za pojedine sustave korišteno je više metoda, ali teško ih je uspoređivati. U stvaranju modela bili su uključeni samo oni parametri koji su doprinosili ostvarivanju ciljeva istraživanja, dok su neki bili zanemareni ili svedeni na najmanji utjecaj kako bi model postigao lakše rješenje. Vrednovanje simulacijskih modela zahtijevalo je stvaranje niza modela. Svaki od njih nastajao je u posebnim uvjetima, a neki su preuzeti kao gotovi i poslužili su samo kao dio stvaranja većeg broja simulacijskih modela. Veći broj uzoraka dovodi do boljih rješenja. U radu su obavljena određena simuliranja kao i mjerenja na simulatoru. Kreiranjem novijih modela dolazi se do optimiziranja brodskog elektroenergetskog sustava, predlažu se učinkovitija rješenja, pokušava se stvoriti okruženje u kojem posada može udovoljiti zahtjevima novih tehnologija, izraditi smjernice za dijagnostiku, kreirati suvremeni simulator kojim se osigurava redudandnost. It is considerably easier to analyze a maline power system on one of the simulators and to follow the state changes by the appropriate simulation model. The simulation model does not endanger operating conditions, the parts of the plant (generator) do not suffer significant damage, the test limits can be reached (short circuit), and there is no danger for the lives of the crew and the plant itself. Simulation ensures quantitative analysis of the process, which implies that this process takes place over a period of time, that it includes random variables, and uses system resources and a large number of intenelated elements. Simulation of ce1tain processes will provide us with answers to the questions such as: What if the machine in operation fails? What if the need for greater fuel efficiency increases? ... For certain systems, several methods were used, but they are difficult to compare. When creating the model, only those parameters that contributed to achieving the research objectives were included. Some other parameters were either ignored or their impact reduced to minimum, so that the model could achieve easier solution. The evaluation of simulation models required creation of a series of models. Each of them was created in special conditions. Some of them were even taken as finished and served only as one part in creation of a larger number of simulation models. Larger number of samples leads to better solutions. This paper deals with simulations as well as measurements in the simulator. Creating new models results in optimizing the marine power system and proposing more efficient solutions, with intention to create an environment in which crew can meet the demands of new technologies, to develop guidelines for diagnosis and to create a modem simulator which provides redundancy.

This paper presents the results of a field study about the domestic shipping companies, in conditions of globalization, in terms of business complexity and of quality of cost systems. The most important is to explore their impact on the quality of managerial decision making. In the eighties, many companies experienced that their traditional cost systems were unable to provide the relevant cost information in the business decision-making process. Traditional cost systems, in terms of business complexity, were unable to estimate the effect of strategic choices based on costs and profits.

Izravna primjena pojedinih simulacijskih modela ne može se odmah provjeriti u konkretnim sustavima. Naime kvarovi, učestala stanja kvara, neefikasnost sustava su upravo doveli do stvaranja modela i provjera sa izmjerenim vrijednostima upućuje efikasnost i znatno bolja tehnička rješenja...

Electrical power system of ship is consisted of power generators, consumers and distribution system. All parts of power system onboard, with or without its own controllers, are interconnected with control system – hardwired or field bus. That provides enormous possibilities for advanced overall control system functionality. The Power Management System (PMS) is a critical part of the control equipment in the ship. It is usually distributed on various control stations that can operate together and share information between each other or independently in case of special emergency situations in which ship have to operate. The equipment within the PMS includes the engines, generators, switchboards and controls along with the automation equipment that perform the calculation algorithms. The design of future ship will require the development of new and increasingly sophisticated methods for the modeling and simulation of the complex systems that must be integrated in order to produce the total ship. Control architecture for power distribution systems has to be hierarchical, distributed and easy to adapt. A complete logistic chain of this control architecture will be modeled by Colored Petri Net (CPN), which connects effective agents for autonomous control of complex distributed systems with agents for the control of power management systems. After introducing the basic Petri Nets concepts, the cooperation and optimization process among the agents is modeled by the CPN Tools developed. The interdependency between these agents is mainly related through information and orders. The goal is to develop the model necessary to study the characteristics of complex systems and support the validity of the integrated control architecture. The results should show that the CPN model provides an effective simulation environment and enhances the power management system on ships.