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Sažetak Međunarodna regulativa sve je strožija u pogledu sigurnosti plovidbe i zagađivanja okoliša. Mogućnost rješavanja problematike leži u poboljšanju funkcija upravljanja i održavanja broda uz široko korištenje informacijske tehnologije što je omogućio napredak u komunikacijskoj tehnologiji. Na osnovu prikaza automatizacije brodskih sustava u prethodnom periodu u ovom radu razmatraju se poboljšanja koja se mogu očekivati u skoroj budućnosti. Razvoj automatizacije na brodu prikazan je kroz četiri generacije. Dane su karakteristike pojedinih generacija i zahtjevi koje sustav upravljanja i nadzora mora ispuniti da bi pripadao određenoj generaciji. Razmatraju se buduća područja poboljšanja sustava upravljanja i nadzora koja će biti odlučujuća za povećanje efikasnosti poslovanja i sigurnosti broda. Da bi se poduprla navedena razmatranja prikazana su i trenutna kretanja u razvoju standarda, opreme i sustava, kao i utjecaji na brodovlasnika i posadu. S u m m a r y The international legislation places strict requirements on the safety of navigation and the marine environment. One of the solutions to the problem is to enhance the ship navigation control and maintenance, with extensive use of information technology which has largely contributed to the growth of communication technology. On the basic of an analysis of ship systems automation existing in the past, this paper deals with the developments and improvements to be expected in the near future. Four generations of shipboard automation are shown, including the characteristics and requirements that the automation of ship control and monitoring systems must meet in order to be classified under a particular generation. Fields of futher enhancement are considered as these will be decisive in increasing the efficiency of the business operations and safety of the ship. For the purpose of supporting the claims above, actual trends in the development of standards, equipment and systems have been analysed as well as their impact on the ship owner and the crew.

Different approaches to teaching the same known things presented through the case study in this paper resulted in better student class attendances, their successful efforts and increased motivation when dealing with tasks, and finally higher exam grades.

By adjusting the maintenance approach towards the significant components of the ship’s engines and equipment, through the use of operation data from the ship machinery's daily reports, a higher operability and navigation safety can be achieved. The proposed maintenance adjustment model consists of an operation data analysis and a risk analysis. The risk analysis comprises the definition of the upper and the lower risk criterion, as well as the definition of a risk index. If the risk index is higher than the lower risk criterion, the component is significant, while it is not significant and has an acceptable risk index if the risk index is lower than the lower risk criterion. For each significant component with a risk index found to be "unacceptable" or "undesirable", an efficient maintenance policy needs to be adopted. The assessment of the proposed model is based on data regarding the power engine original operation throughout a 13-year period. Results of engine failure examinations reveal that the exhaust valve is the most vulnerable component with the highest rate of failure. For that reason the proposed model of adjusting the maintenance approach has been tested on the exhaust valve sample. We suggest that the efforts to achieve a higher ship operability and navigation safety should go in the direction of periodical adjustments of the maintenance approach i.e. choosing an efficient maintenance policy by reducing the risk indices of the significant engine components.

Sve stroži propisi o zaštiti okoliša, a i potreba za što boljim iskorištavanjem goriva postavljaju pred konstruktore motora sve veće zahtjeve. Razvoj numeričkih metoda, a istovremeno i porast snage računala omogućavaju provjeru novih ideja još u ranoj fazi razvoja motora. U radu je dan pregled mogućnosti programskog paketa AVL-BOOST firme AVL iz Graza. Opisano je grafičko sučelje koje omogućava korisnicima s osnovnim znanjem o simulacijskoj tehnologiji da u kratkom vremenu ovladaju programom. Predstavljen je model jednocolindričnog motora, izvršena je simulacija rada te analizirani dobiveni rezultati., The more and more rigorous regulations on the environmental protection, as well as the need for a much better fuel exploitation, have raised greater demands on the designer. The development of numerical methods and, at the same time, a computing power growth, makes the checking of new ideas possible, even in the early stage of the engine development. The paper aims at presenting a survey of all the possibilities offered by the AVL-BOOST software produced by the firm AVL from Graz: A graphical interface, that enables the user with only a basic knowledge of a simulation technology to master the computer programme in a very short time, has been described too. A one-cylinder engine model has been presented and its operation simulated. The results thus obtained have been analyzed.

U radu izložen je način održavanja brodskog pogona, koji obuhvaća sistem brodskog održavanja, pristupe brodskog održavanja i održavanje u brodskom životnom ciklusu. U sistem brodskog održavanja ulaze četiri glavna faktora koji utječu na funkcionalnost održavanja broda. To su operater, okolina (luke pristajanja, luke u slučaju potrebe, klima, uvjeti na moru), zakoniost (propise koje brod mora zadovoljiti) i samo održavanje. Predočen je pregled pristupa održavanja u poslijednjih trideset godina. Korektivno održavanje je najstariji model održavanja opreme, a izvodi se nakon što je došlo do kvara. Preventivno održavanje može biti periodično i preventivno održavanje prema stanju. Kod periodičnog PM održavanja interval održavanja može biti baziran na kalendaru ili vremenu rada (vijeku). Politika periodičnog održavanja bazirana na vijeku (periodi održavanja po instrukcijskim knjigama proizvođača) općenito se koristi na brodovima. Preventivnog održavanja prema stanju može biti povremeno i kontinuirano. Prikazana je struktura troškova održavanja, kao i sve faze održavanja u brodskom životnom ciklusu

On-board ship, the integrated platform control and monitoring systems (IPCMS) would undertake and manage all activities associated with the administration of the vessel, including stores and provisions management, work requests, logs, equipment tag outs and calling up and display of diagnostics, drawings and work procedures for engineering repair teams. Because of the growing amount of data and the evolving technology, the operators have to deal with more and faster information streams. The decision-making processes will become more complicated, the IPCMS systems more extensive. Furthermore there is a growing demand for reduction of the number of crewmembers onboard. New technology and new IPCMS functions will handle these issues. The next paragraphs describe the authors view regarding the trends in IPCMS systems.

Selecting of proper maintenance strategy for ship systems, we are faced with a two important problems, merely technological in nature. First problem is to define optimal inspection interval for equipment. Few mathematical models have been developed, and because of complexity of it, it is very important to understand a “ key” signals which defines a state of the equipment. Second problem is how to optimise a preventive maintenance actions. Following instructions of producers, additional maintenance action are performed, which are unnecessary under real exploitation conditions. Rationalisation of maintenance preventive actions has been discussed and their effects have been done in present work.

Every maintenance system can be improved, as is selecting a choice of improving and obtaining better results. Because of that it is necessary to analyse a problem and tray to apply other modern strategy and approaches, based on experience and research by others authors and data from word literature. On base of analysed strategy a proposal has been made for selecting a maintenance strategy based on conditions and different combinations.

If we are to enable the marine engineer to operate effectively in the electronic age, we must first understand the factors that influence this objective. The solution obviously lies in the successful integration of people and technology, but we often think of systems (specifically automation systems) as comprising only hardware and software. Current generation control systems, including those aboard the “ Smart Ships” , place an ever-increasing amount of sensory information in front of the operator, and generally require sharply increased manning in the event of control system malfunctions. Furthermore there is a growing demand for reduction of the number of crewmembers onboard. The control system designer faces the challenge of designing a robust and increasingly autonomous automation system that is scalable and affordable. Research suggests these challenges will be met by three - tiered control architecture – a strategic layer that focuses on setting resource goals and priorities for machinery systems based on the ship’ s current mission. This will enhance the features of currently available systems by allowing direct addressing of any system component, sensor or actuator from anywhere in a vessel. This permits system self-reconfiguration on failure or in the event of damage to segments of the system.

Analysis of surface ships and submarines loss has shown that the ship survivability is very much dependent on the possibility of the mechanical engineer on watch and the ship commanding officer to take fast and adequate decisions in the emergency situation aimed at its localization and elimination under conditions of the rapidly changing enormous flow of incoming information. Wide introduction of computers on ships makes it possible to realize the complicated task under consideration ensuring efficiency and safety of the modern ship control.

Studije dokazuju da mnoge vrste bakteria- patogena, biljaka i životinja mogu preživjeti u balastnoj vodi i sedimentu koji se prenosi brodom, čak i nakon putovanja u trajanju od nekoliko tjedana. Naredni iskrcaj balastne vode ili sedimenta u luci može rezultirati utemeljenjem štetih vrsta, koje mogu ozbiljno poremetiti ekološku ravnotežu. Premda su i drugi mediji označeni za prijenos organizama između geografski odvojenih vodenih masa, iskrcaj balastne vode iz brodova javlja se među najistaknitijima. Unos bolesti može se također pojaviti kao rezultat voda u luci u koju je ulivena znatna količina balastne vode koja sadrži viruse, bakterije i druge škodljive organizme i zato treba zaštititi prirodni ljudski, životinjski, biljni život i morski okoliš. Odabir odgovarajuće metode za minimiziranje rizika ovisi od nekoliko faktora, uključujući: vrste ciljanih organizama, nivo rizika, njihove prihvatljivosti u okolišu, ekonomskih i ekoloških troškova i sigurnosti brodova.

In the 21st centry the integrated of propulsion, auxillary, energy, sensor and systems on board of ships will make these systems more complex and interdependent. Furthermore the growing importance of economic interests and growth of technical possibilites to fulfil modern requirements as well as further technology and legislation evolution make the design decision process more difficult. Simulation tools are uttilized for the design and analysis of specific aspects of the propulsion and energy system. Simulation tools have their own capabilities, specialities, adventages and disadventages. It is simply not possible or to complicated to have a single tool that combines all the capabilities of the different tools. It is therefore necessary to have different tools to study different aspects of a system. At research laboratories and industry several other simulation are utilised for studying electrical energy systems, such as MATLAB/Simulink, PSCAD/EMTDC, Flux2D, PSpice - The Design Centre and a number of other programs. Linking the several simulation tools and models has become an important step in the design process.

Lead-acid batteries dominate marine energy-storage, althougt they have some widely recognised weaknesses of perfomance and reliability. This paper present an overview of alternative technologies and thier advantages to the marine engineer. Some technologies are identifield as particulary suitable for specific duites, from the range of new requirements emerging from the development of ship platform concepts.

Where a loss of propulsion, even for a short period of time, may not be tolerated due to the possible undesirable consequences in commercial and environmental terms, then ship owners are driven to resort to more rigorous redundant design in order to reduce the risk. Some tanker owners are currently considering various different redundant solutions. This paper investigates the potential weaknesses of the conventional propulsion systems, and narrowed down the areas of enhancement which can be made in order to make the vessels’ propulsion system even more fault tolerant.

Reliability Centered Maintenance (RCM) method has been approved as very successful in various industry fields, increasing the reliability and safety of equipment and systems, by better quality of maintenance. The basic goal of RCM method is to find out a most effective maintenance task and actions optimized with respect to the criticality of unplanned failures, and improving availability of equipments and systems, and reduced costs. To reach this goal RCM needs to collect continuously operational data and make eficient analisys to find most effective maintenance tasks and actions, what is well suited for maintenance information system software. Maintenace information system software are analized and some proposal of their improvement are done.

Reliability Centered Maintenance (RCM) method has been approved as very successful in aircraft industry and power plant industry, increasing the reliability and safety of equipment and systems, by betteris quality of maintenance. In the recent time the RCM method has been introduced also in commercial shipping. The basic goal of RCM method is to find out a most effective maintenance tasks and actions optimized with respect to the criticality of unplanned failures, and improving availability of equipments and systems, and reduced costs. This requires continues collection of operational data and a tool for efficient analysis to find the most effective maintetnance tasks and actions to avoid systems and equipment failures. Computere-based model are proposed for efficient onboard data acquisition, efficient information flow between the ship and the owner`s office and further to external parties like suppliers and classifcation societies. The attributes of model are: interface to ship control system for automated data acquisition, possibility for reporting of conditions of equipment and systems and open structure of model. The goal of model is to present a engineer tool for RCM application in commercial shipping.

Electric power system stability and integrity have great importance for the ship's safety. The most serious fault in the electrical system is a short circuit fault. It can cause an explosion, fire, mechanical and thermic damages, the system instability and the loss of services. Harmful effects of the short circuit fault depend on its duration. Numerical protection, thanks to the fully adjustable cut-off characteristic and intelligent operation based on data exchange, disconnects the short circuit much faster than classic protection relays. It is simpler for use, and has high reliability as well as the possibilities of data collection and integration into the complex systems for both, electric power and technological systems control and monitoring. Highly valuable information achieved by numerical relays can be used for fast fault diagnosis and the technical and economical analyses of the ship's electric power system.

This paper describes a proposal of maintenance system improvements applying RCM method in order to achieve better quality of maintenance of ship systems and equipment. Increased requirements for safety and environmental control, and growing competition on the market, have challenged commercial shipping to cope with new developments. One choice is the improvement of safety and reliability as wellas increased efficiency, apppling the RCM method. RCM method was born as a need of continuous improvements on reliability and safety in air transport, and recently it has found numerous applications in other fields. A great advantage of RCM method lies in the fact that it gives a maintenance plan, optimised with respect to the criticality of unplanned failures. It also improves the availability of equipment and systems and reduces cost. The work described in this paper focuses on the use of RCM method for criticality assesment of equipment and systems, and criticality assesement of functions. According to the application of the above method, an initial maintenance plan is created which however, is subject to modification according to back information obtained from its application.