Sustavsko dinamicko simulacijsko modeliranje je jedna od najprimjerenijih i najuspjesnijih znanst... more Sustavsko dinamicko simulacijsko modeliranje je jedna od najprimjerenijih i najuspjesnijih znanstvenih nacina modeliranja dinamike složenih, nelinearnih, prirodnih, tehnickih i organizacijskoh sustava. Proucavanje dinamike ponasanja brodskog pogonskog sustava, ako jednog od složenih, dinamickih, nelinearmih, tehnickih sustava, zahtijeva primjenu najucinkovitijih metoda modeliranja. U vremenskom peridu od 1991-2001., prilikom izrade diplomskih radova, na Pomorskom fakultetu u Splitu, koristila se sustavska dinamicka kompjuterska simulacijska metodologija za modeliranje dinamike ponasanje veceg broj nelinearnih brodskih elektroenergentskih, termodinamickih, hidraulicnih, mehanickih i pneumatskih sustava. Svrha ovog djela jest: pokazati uspjesnost primjene sustavsko dinamickog simulacijskog modeliranja pri istraživanju dinamike ponasanja pogonskog sustava BSVPAM-a. Brodko sidrene vitlo i njegov pogonski asinkroni motor bit ce predstavljeni mentalno-verbalnim, strukturnim i matematicko-kompjuterskim modelima! Sustavsko dinamicki modeli su u sustini kontinuirani modeli jer se realiteti predstavljaju skupom nelinearnih diferencijalnih jednadžbi, tj. "jednadžbi stanja"! Međutim, oni su istovremeni i diskretni jer im se osnovni vremenski korak racunanja, tj. diskretizacije (uzorkovanja) "DT" određuje u potpunom skladu s "Teoremom o uzorkovanju" (Sampling Teorem) Shannona i Koteljnikova! Ovakav odabir osnovnog vremenskog koraka DT omogucuje kompjtersko modeliranje kontinuiranih simulacijskih modela na digitalnom racunalu, sto je veoma primjereno za edukaciju studenata pomorstva, strojarstva i elektrotehnike, te za teoretsko i prakticno trenažiranje brodskih sustava, jer im omogucuju stjecanje novih znanja i vjestina o složenoj dinamici ponasanja sustava i provesa
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
International Conference on Software, Telecommunications and Computer Networks, 1999
Satellites are more and more used every day. We considered satellite transmission coding in case ... more Satellites are more and more used every day. We considered satellite transmission coding in case of sensitive data, i.e. telemedicine data. Wavelet compression gives an opportunity to prevent unwanted reception by unauthorised parties, as well as the compression of the data. Wavelet properties enable coding usage in the transmission of sensitive data, such as patients' documentation in the telemedicine systems. A new way of three-level coding is proposed. An example of the X-ray pulmonary images has been shown.
Alati kvalitete u određivanju karakteristika usluge u pomorskom putničkom prometu KEY WORDS marit... more Alati kvalitete u određivanju karakteristika usluge u pomorskom putničkom prometu KEY WORDS maritime passenger transport fast passenger transport quality function deployment (QFD) Ishikawa diagram characteristics of maritime passenger transport service
This paper presents the measurement process of the emissions from marine diesel engines. The emis... more 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 (CO 2), oxygen (O 2) and sulfur dioxide (SO 2). 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".
Elektromotorna propulzija prosla je u svom razvoju kroz nekoliko faza koje su vezane za dostignuc... more Elektromotorna propulzija prosla je u svom razvoju kroz nekoliko faza koje su vezane za dostignuca proizvodnih snaga i pripadajucih tehnickih sustava. Najznacajnija dostignuca su povezana s razvojem energetske elektronike koja doprinosi fleksibilnosti, sigurnosti, cijeni, smanjenim troskovima održavanja i sl. Elektricni porivni pogon nude neke znacajne prednosti, tj. nadilaze prvi trosak, te se koriste kada njihova lakoca kontrole, smjestaj i upotrebljivost može postici određene prednosti pa je zbog toga vec u prvoj fazi (fazi projektiranja) potrebno izvrsiti pravilan odabir propulzijskog sustava.
The integrated ship networks connected via satellite and terrestrial networks become an integral ... more The integrated ship networks connected via satellite and terrestrial networks become an integral part of the global network. In this way, participants in marine traffic are offered the benefits of broadband integrated services regardless of distance or position of their vessels. This paper deals with the need for introducing integrated network and multimedia services into the Croatian Merchant Navy ships. The basic criteria to be used in evaluating high-speed LAN technologies for supporting multimedia applications are given and their usage in the evaluation of these technologies when used in the ship LAN backbones is shown. The appropriate LAN backbone technology for ships of the Croatian Merchant Navy is proposed.
TransNav: International Journal on Marine Navigation and Safety of Sea Transportation, 2020
Traffic congestion is a wide problem in many tourist destinations. Airports are usually distant f... more Traffic congestion is a wide problem in many tourist destinations. Airports are usually distant from the city centers. Hence, road and rail traffic are widely used to connect airports and city centers. In this paper, we propose zero-emission solution for connection between airport and the center at the example of Croatian city Split. Since Split has become a popular tourist destination, the number of vehicles during summer season increases. As a measure to decrease air pollution, in this paper the marine traffic by electric vessels is proposed for the route Split-airport. Seven all-electrical vessels are presented with their technical characteristics. The idea is to have zero emission transfers by sea from the center of the Split to the airport. The criteria for minimum cruising speed is set to 13 knots, which ensures that one crossing takes 30 minutes and makes it competitive with other forms of transport.
The paper discusses the contribution to energy efficiency by reducing the dimensions of the main ... more The paper discusses the contribution to energy efficiency by reducing the dimensions of the main switchboard (medium voltage or High Voltage-used on ship). Reducing the dimensions of the switchboards can be achieved by reducing the dimensions of the bus bars, while fully satisfying the conditions with regard to thermal and mechanical stresses. The same can be achieved by modifying some other components, such as the application of new technology for measuring current and voltage, using current and voltage sensors that fall into the category of completely new technological solutions. By replacing conventional measuring transformers (IT), compact and efficient sensor technology significantly contributes to reducing the dimensions and mass of switchboards, which ultimately contributes to energy efficiency. Previous applications, the possibility of improving existing solutions, especially in applications in marine power systems, and new technological solutions that contribute to the efficiency of the marine power system using the Rogowski coil sensor and voltage divider voltage sensors are also considered.
Brodski elektroenergetski sustav je znatno jednostavnije analizirati na nekom od simulatora ili o... more Brodski elektroenergetski sustav je znatno jednostavnije analizirati na nekom od simulatora ili odgovarajucim simulacijskim modelima pratiti promjen
ABSTRACT Technological improvements and innovations slowly and hardly penetrate into the power sy... more ABSTRACT Technological improvements and innovations slowly and hardly penetrate into the power system on floating object. It is necessary to establish a system of testing and proving of innovation that the new system more secure and reliable, especially those that are fully automated. Automation is increasingly applied to the board and although there are great benefits and obstacles that if not well prepared may lead to reduced rather than enhanced operational efficiency, and even to large additional costs of repairs and serious accidents. Efficient automation depends on the expertise of the staff, which in turn depends on the education of the crew. It is important to know what level of competence has the current crew, which the crew on arrival. It is impossible to link one crew with concrete ship, but it is important that the ships have similar characteristics to obtain a general conclusion of the implementation of modern technology. Electronic components and computer technology are going through a dynamic development and there are reasons for the increased use of electronic equipment in marine systems, even for less complex tasks. This requires considerable efforts in training the crew in order to monitor the development and application of new technologies, especially for the engineer officers. UTJECAJI AUTOMATIZACIJE NA EDUKACIJU BRODSKE POSADE SAŽETAK Tehnološki razvoj i novine koje on donosi polako i teško prodiru u elektroenergetske sustave na plovnim objektima. Potrebno je uspostaviti sustav ispitivanja i dokazivanja inovacija kako bi novi sustavi postali sigurni i pouzdani, posebno oni koji su u potpunosti automatizirani. Automatizacija se sve više primjenjuje na brodu pa iako je korist velika tu su i zapreke za koje ako nismo dobro pripremljeni mogu dovesti 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. Važno je znati koju razinu osposobljenosti ima trenutna posada, a koju posada na dolasku. Nemoguće je ostvariti povezanost posade s konkretnim brodom, ali je važno da brodovi budu sličnih karakteristika da bi se dobio opći zaključak implementacije modernih elektroničkih uređaja. 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 časnike stroja.
Mjerno osjetilo svakog pretvornika tlaka fluida s elektrootpornim mjernim trakama, koje se korist... more Mjerno osjetilo svakog pretvornika tlaka fluida s elektrootpornim mjernim trakama, koje se koristi u brodskim postrojenjima, najkriticnija je njegova mehanicka komponenta. U radu je data usporedna analiza naprezanja i deformacija jednog novog konstrukcijskog rjesenja mjernog osjetila, oblika kružne membrane ojacane koncentricnim rebrima zbog povecanja krutosti na savijanje. Kako egzaktno rjesenje ne postoji , na osnovi analitickog rjesenja koje se temelji na metodi pocetnih parametara, te odgovarajuceg programa za racunalo, dobivene su ekstremne vrijednosti naprezanja i progibi membrane. Kao eksperimentalna metoda koristena je fotoelasticna metoda zamrzavanja naprezanja posebno izrađenog i opterecenog modela. Potvrđena je valjanjost razmatranog konstrukcijskog rjesenja i predložene proracunske metode.
Najkriticnija mehanicka komponenta svakog pretvornika tlaka fluida je njegovo mjerno osjetilo, ci... more Najkriticnija mehanicka komponenta svakog pretvornika tlaka fluida je njegovo mjerno osjetilo, cija je zadaca da reagira na narinuto opterecenje. U ovom je radu provedena elastomehanicka analiza jednog novog konstrukcijskog rjesenja mjernog osjetila oblika orebrene kružne ploce. Rezultati predloženog analitickog rjesenja uspoređeni su s eksperimentalnim rezultatima dobivenim fotoelasticnim postupkom zamrzavanja naprezanja. Potvrđena je valjanost predložene konstrukcije kao i proracunski postupci.
International Conference on Systems, Signals and Image Processing, 1998
The integrated ship networks connected via satellite and terestrial networks become an integral p... more The integrated ship networks connected via satellite and terestrial networks become an integral part of the global etwork. in this way, participants in marine traffic are offered the benefits of broadband integrated services regardless of distance or position of their vessels. This paper deals with the need for introducing integrated network and multimedia services into the Croatian Merchant Navy ships. The basic criteria to be used in evaluating high-speed LAN technologies for suporting multimedia applications are given and their usage in the evaluation of these technologies ewhen used in the ship LAN backbones is shown. The appropriate LAN backbone technology for ships of the Croatian Merchant Navy is proposed.
Sustavsko dinamicko simulacijsko modeliranje je jedna od najprimjerenijih i najuspjesnijih znanst... more Sustavsko dinamicko simulacijsko modeliranje je jedna od najprimjerenijih i najuspjesnijih znanstvenih nacina modeliranja dinamike složenih, nelinearnih, prirodnih, tehnickih i organizacijskoh sustava. Proucavanje dinamike ponasanja brodskog pogonskog sustava, ako jednog od složenih, dinamickih, nelinearmih, tehnickih sustava, zahtijeva primjenu najucinkovitijih metoda modeliranja. U vremenskom peridu od 1991-2001., prilikom izrade diplomskih radova, na Pomorskom fakultetu u Splitu, koristila se sustavska dinamicka kompjuterska simulacijska metodologija za modeliranje dinamike ponasanje veceg broj nelinearnih brodskih elektroenergentskih, termodinamickih, hidraulicnih, mehanickih i pneumatskih sustava. Svrha ovog djela jest: pokazati uspjesnost primjene sustavsko dinamickog simulacijskog modeliranja pri istraživanju dinamike ponasanja pogonskog sustava BSVPAM-a. Brodko sidrene vitlo i njegov pogonski asinkroni motor bit ce predstavljeni mentalno-verbalnim, strukturnim i matematicko-kompjuterskim modelima! Sustavsko dinamicki modeli su u sustini kontinuirani modeli jer se realiteti predstavljaju skupom nelinearnih diferencijalnih jednadžbi, tj. "jednadžbi stanja"! Međutim, oni su istovremeni i diskretni jer im se osnovni vremenski korak racunanja, tj. diskretizacije (uzorkovanja) "DT" određuje u potpunom skladu s "Teoremom o uzorkovanju" (Sampling Teorem) Shannona i Koteljnikova! Ovakav odabir osnovnog vremenskog koraka DT omogucuje kompjtersko modeliranje kontinuiranih simulacijskih modela na digitalnom racunalu, sto je veoma primjereno za edukaciju studenata pomorstva, strojarstva i elektrotehnike, te za teoretsko i prakticno trenažiranje brodskih sustava, jer im omogucuju stjecanje novih znanja i vjestina o složenoj dinamici ponasanja sustava i provesa
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
International Conference on Software, Telecommunications and Computer Networks, 1999
Satellites are more and more used every day. We considered satellite transmission coding in case ... more Satellites are more and more used every day. We considered satellite transmission coding in case of sensitive data, i.e. telemedicine data. Wavelet compression gives an opportunity to prevent unwanted reception by unauthorised parties, as well as the compression of the data. Wavelet properties enable coding usage in the transmission of sensitive data, such as patients' documentation in the telemedicine systems. A new way of three-level coding is proposed. An example of the X-ray pulmonary images has been shown.
Alati kvalitete u određivanju karakteristika usluge u pomorskom putničkom prometu KEY WORDS marit... more Alati kvalitete u određivanju karakteristika usluge u pomorskom putničkom prometu KEY WORDS maritime passenger transport fast passenger transport quality function deployment (QFD) Ishikawa diagram characteristics of maritime passenger transport service
This paper presents the measurement process of the emissions from marine diesel engines. The emis... more 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 (CO 2), oxygen (O 2) and sulfur dioxide (SO 2). 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".
Elektromotorna propulzija prosla je u svom razvoju kroz nekoliko faza koje su vezane za dostignuc... more Elektromotorna propulzija prosla je u svom razvoju kroz nekoliko faza koje su vezane za dostignuca proizvodnih snaga i pripadajucih tehnickih sustava. Najznacajnija dostignuca su povezana s razvojem energetske elektronike koja doprinosi fleksibilnosti, sigurnosti, cijeni, smanjenim troskovima održavanja i sl. Elektricni porivni pogon nude neke znacajne prednosti, tj. nadilaze prvi trosak, te se koriste kada njihova lakoca kontrole, smjestaj i upotrebljivost može postici određene prednosti pa je zbog toga vec u prvoj fazi (fazi projektiranja) potrebno izvrsiti pravilan odabir propulzijskog sustava.
The integrated ship networks connected via satellite and terrestrial networks become an integral ... more The integrated ship networks connected via satellite and terrestrial networks become an integral part of the global network. In this way, participants in marine traffic are offered the benefits of broadband integrated services regardless of distance or position of their vessels. This paper deals with the need for introducing integrated network and multimedia services into the Croatian Merchant Navy ships. The basic criteria to be used in evaluating high-speed LAN technologies for supporting multimedia applications are given and their usage in the evaluation of these technologies when used in the ship LAN backbones is shown. The appropriate LAN backbone technology for ships of the Croatian Merchant Navy is proposed.
TransNav: International Journal on Marine Navigation and Safety of Sea Transportation, 2020
Traffic congestion is a wide problem in many tourist destinations. Airports are usually distant f... more Traffic congestion is a wide problem in many tourist destinations. Airports are usually distant from the city centers. Hence, road and rail traffic are widely used to connect airports and city centers. In this paper, we propose zero-emission solution for connection between airport and the center at the example of Croatian city Split. Since Split has become a popular tourist destination, the number of vehicles during summer season increases. As a measure to decrease air pollution, in this paper the marine traffic by electric vessels is proposed for the route Split-airport. Seven all-electrical vessels are presented with their technical characteristics. The idea is to have zero emission transfers by sea from the center of the Split to the airport. The criteria for minimum cruising speed is set to 13 knots, which ensures that one crossing takes 30 minutes and makes it competitive with other forms of transport.
The paper discusses the contribution to energy efficiency by reducing the dimensions of the main ... more The paper discusses the contribution to energy efficiency by reducing the dimensions of the main switchboard (medium voltage or High Voltage-used on ship). Reducing the dimensions of the switchboards can be achieved by reducing the dimensions of the bus bars, while fully satisfying the conditions with regard to thermal and mechanical stresses. The same can be achieved by modifying some other components, such as the application of new technology for measuring current and voltage, using current and voltage sensors that fall into the category of completely new technological solutions. By replacing conventional measuring transformers (IT), compact and efficient sensor technology significantly contributes to reducing the dimensions and mass of switchboards, which ultimately contributes to energy efficiency. Previous applications, the possibility of improving existing solutions, especially in applications in marine power systems, and new technological solutions that contribute to the efficiency of the marine power system using the Rogowski coil sensor and voltage divider voltage sensors are also considered.
Brodski elektroenergetski sustav je znatno jednostavnije analizirati na nekom od simulatora ili o... more Brodski elektroenergetski sustav je znatno jednostavnije analizirati na nekom od simulatora ili odgovarajucim simulacijskim modelima pratiti promjen
ABSTRACT Technological improvements and innovations slowly and hardly penetrate into the power sy... more ABSTRACT Technological improvements and innovations slowly and hardly penetrate into the power system on floating object. It is necessary to establish a system of testing and proving of innovation that the new system more secure and reliable, especially those that are fully automated. Automation is increasingly applied to the board and although there are great benefits and obstacles that if not well prepared may lead to reduced rather than enhanced operational efficiency, and even to large additional costs of repairs and serious accidents. Efficient automation depends on the expertise of the staff, which in turn depends on the education of the crew. It is important to know what level of competence has the current crew, which the crew on arrival. It is impossible to link one crew with concrete ship, but it is important that the ships have similar characteristics to obtain a general conclusion of the implementation of modern technology. Electronic components and computer technology are going through a dynamic development and there are reasons for the increased use of electronic equipment in marine systems, even for less complex tasks. This requires considerable efforts in training the crew in order to monitor the development and application of new technologies, especially for the engineer officers. UTJECAJI AUTOMATIZACIJE NA EDUKACIJU BRODSKE POSADE SAŽETAK Tehnološki razvoj i novine koje on donosi polako i teško prodiru u elektroenergetske sustave na plovnim objektima. Potrebno je uspostaviti sustav ispitivanja i dokazivanja inovacija kako bi novi sustavi postali sigurni i pouzdani, posebno oni koji su u potpunosti automatizirani. Automatizacija se sve više primjenjuje na brodu pa iako je korist velika tu su i zapreke za koje ako nismo dobro pripremljeni mogu dovesti 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. Važno je znati koju razinu osposobljenosti ima trenutna posada, a koju posada na dolasku. Nemoguće je ostvariti povezanost posade s konkretnim brodom, ali je važno da brodovi budu sličnih karakteristika da bi se dobio opći zaključak implementacije modernih elektroničkih uređaja. 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 časnike stroja.
Mjerno osjetilo svakog pretvornika tlaka fluida s elektrootpornim mjernim trakama, koje se korist... more Mjerno osjetilo svakog pretvornika tlaka fluida s elektrootpornim mjernim trakama, koje se koristi u brodskim postrojenjima, najkriticnija je njegova mehanicka komponenta. U radu je data usporedna analiza naprezanja i deformacija jednog novog konstrukcijskog rjesenja mjernog osjetila, oblika kružne membrane ojacane koncentricnim rebrima zbog povecanja krutosti na savijanje. Kako egzaktno rjesenje ne postoji , na osnovi analitickog rjesenja koje se temelji na metodi pocetnih parametara, te odgovarajuceg programa za racunalo, dobivene su ekstremne vrijednosti naprezanja i progibi membrane. Kao eksperimentalna metoda koristena je fotoelasticna metoda zamrzavanja naprezanja posebno izrađenog i opterecenog modela. Potvrđena je valjanjost razmatranog konstrukcijskog rjesenja i predložene proracunske metode.
Najkriticnija mehanicka komponenta svakog pretvornika tlaka fluida je njegovo mjerno osjetilo, ci... more Najkriticnija mehanicka komponenta svakog pretvornika tlaka fluida je njegovo mjerno osjetilo, cija je zadaca da reagira na narinuto opterecenje. U ovom je radu provedena elastomehanicka analiza jednog novog konstrukcijskog rjesenja mjernog osjetila oblika orebrene kružne ploce. Rezultati predloženog analitickog rjesenja uspoređeni su s eksperimentalnim rezultatima dobivenim fotoelasticnim postupkom zamrzavanja naprezanja. Potvrđena je valjanost predložene konstrukcije kao i proracunski postupci.
International Conference on Systems, Signals and Image Processing, 1998
The integrated ship networks connected via satellite and terestrial networks become an integral p... more The integrated ship networks connected via satellite and terestrial networks become an integral part of the global etwork. in this way, participants in marine traffic are offered the benefits of broadband integrated services regardless of distance or position of their vessels. This paper deals with the need for introducing integrated network and multimedia services into the Croatian Merchant Navy ships. The basic criteria to be used in evaluating high-speed LAN technologies for suporting multimedia applications are given and their usage in the evaluation of these technologies ewhen used in the ship LAN backbones is shown. The appropriate LAN backbone technology for ships of the Croatian Merchant Navy is proposed.
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