Repository of the University of Rijeka, Faculty of Maritime Studies
Not a member yet
3513 research outputs found
Sort by
A contribution to the improvement of collision alerting at sea
No full textSudari na moru predstavljaju jedne od najtežih vrsta nezgoda s obzirom na to da mogu dovesti u opasnost ljude i okoliš te nanijeti veliku ekonomsku štetu. Međusobni odnosi brodova te potrebne radnje kako bi se izbjegli sudari uređeni su pravilima o izbjegavanju sudara na moru. Pravila, nastala u prošlom stoljeću, upućena su članovima plovidbene straže koji donose odluke na temelju vlastitog znanja, iskustva i vještina, imajući na umu sigurnost plovidbe. Međutim, pravila kao takva često koriste pojmove koji su nejasni ili neizraziti te njihova kvantifikacija predstavlja poteškoće razvoju modernih inteligentnih navigacijskih sustava. Neizraziti pojmovi mogu se jednostavno matematički opisati koristeći svojstva neizrazitih skupova i neizrazitih sustava. Budući da je procjena rizika sudara na moru stvar odluke člana plovidbene straže, u ovom se radu pristupilo modeliranju indeksa rizika sudara koristeći ekspertna znanja uz neizraziti pristup. Istraživanje u svom prvom dijelu određuje čimbenike koje eksperti smatraju bitnima pri procjeni rizika sudara. Rezultati ukazuju na to da su eksperti kao vrlo važne čimbenike pored uobičajenih odabrali i neke druge čimbenike koji imaju utjecaj na procjenu rizika sudara. Svi odabrani čimbenici, u svojoj naravi neizraziti, predstavljaju lingvističke varijable, te su se u drugom dijelu istraživanja kvantificirali koristeći teoriju neizrazitih skupova. Pri tome su se rasponi i oblik lingvističkih varijabli odredili koristeći ekspertno znanje ispitanika, upotrebom trapezoidnih i Gaussovih funkcija pripadnosti. Koristeći odabrane čimbenike, pristupilo se izradi modela neizrazitog sustava zaključivanja za određivanje neizrazitog indeksa rizika sudara. Kako bi se prikazale razlike pri procjeni rizika koje proizlaze iz različitih međusobnih odnosa brodova, potrebno je bilo odrediti više podmodela. Dodatno, s obzirom na mišljenje eksperata, bilo je potrebno kreirati modele u uvjetima smanjene vidljivosti, modelirajući tako poseban oprez kako je on propisan pravilima. Validacijom modela na neovisnom skupu uzoraka odabrani su oni koji su koristili trapezoidne funkcije pripadnosti kao povoljniji. Verifikacijom rezultata studijama slučajeva prikazane su mogućnosti modela neizrazitog sustava zaključivanja. Rezultati indiciraju kako je ostvareno unapređenje protusudarnog uzbunjivanja. Među ostalim, postignuto je pravovremeno uzbunjivanje u nekim situacijama u kojima postojeći sustavi ne bi alarmirali člana plovidbene straže na vrijeme. Dodatno prikazani indeks rizika sudara nije binaran, te dopušta usporedbu brodova s obzirom na neizraziti indeks rizika sudara. Na taj način, model pruža prikaz hijerarhije indeksa rizika sudara. Prikazani neizraziti sustav mogao bi se koristiti kao sustav potpore odlučivanju brodovima s ljudskom posadom. Sustav je također moguće primijeniti za upotrebu autonomnim brodovima. Karakteristike neizrazitih sustava dopuštaju u budućim istraživanjima uvesti dodatne ulazne varijable.Dodatno, moguće je još detaljnije prikazati razlike u procjeni rizika koje proizlaze iz međusobnih odnosa brodova koristeći finiju podjelu podmodela u budućim istraživanjima.Collisions at sea represent one of the most serious types of accidents, considering that they can put people and the environment at risk and cause significant economic damage. The mutual relations of ships and the necessary actions to avoid collisions are governed by the International Regulations for Preventing Collisions at Sea. The rules, created in the last century, are addressed to the members of the navigation watch who make decisions based on their own knowledge, experience and skills, keeping in mind the safety of navigation. However, rules often use unclear or vague concepts, and their quantification presents difficulties for the development of modern intelligent navigation systems. Vague concepts can be easily described mathematically using the properties of fuzzy sets and fuzzy systems. Since the assessment of the risk of collision at sea is a matter of the decision of a member of the navigational watch, in this research, the modelling of the index of collision risk was approached using expert knowledge with a fuzzy approach. In its first part, the research determines the factors that experts consider important when assessing the risk of a collision. The results indicate that the experts choose some other factors that impact the collision risk assessment as very important in the last century, are addressed to the members of the navigation watch who make decisions based on their own knowledge, experience and skills, keeping in mind the safety of navigation. However, rules often use unclear or vague concepts, and their quantification presents difficulties for the development of modern intelligent navigation systems. Vague concepts can be easily described mathematically using the properties of fuzzy sets and fuzzy systems. Since the assessment of the risk of collision at sea is a matter of the decision of a member of the navigational watch, in this research, the modelling of the index of collision risk was approached using expert knowledge with a fuzzy approach. In its first part, the research determines the factors that experts consider important when assessing the risk of a collision. The results indicate that the experts choose some other factors that impact the collision risk assessment as very important in addition to the usual ones. All selected factors, fuzzy in nature, represent linguistic variables and were quantified in the second part of the research using the theory of fuzzy sets. In doing so, the ranges and shapes of the linguistic variables were determined using the respondents' expert knowledge and trapezoidal and Gaussian membership functions. A fuzzy inference system model was created using the selected factors to determine the fuzzy collision risk index. In order to show the differences in risk assessment resulting from different ship relationships, it was necessary to define several sub-models. Additionally, considering the opinion of experts, it was necessary to create models in conditions of reduced visibility, thus modelling due regard as prescribed by the rules. By validating the model on an independent set of samples, those that used trapezoidal membership functions were selected as more favourable. The possibilities of the fuzzy inference system model are shown by verifying the results with case studies. The results indicate that the collision alerting has been improved. Among other things, timely alerting was achieved in some situations where the existing systems would not have alerted the navigation watch member in time. The additionally presented collision risk index is not binary and allows the comparison of ships with regard to the fuzzy collision risk index. In this way, the model provides a representation of the hierarchy of collision risk indices. The presented fuzzy system could be used as a decision support system for manned ships. The system can also be used by autonomous ships. The characteristics of fuzzy systems allow the introduction of additional input variables in future research. Additionally, it is possible to show in more detail the differences in risk assessment arising from ship relationships using a finer subdivision of submodels in future researc
Macroscopic model of transport demand in nautical tourism for the purpose of quantification of traffic volumes and environmental pressures
No full textObalni i pomorski turizam čine najveći sektor plavog gospodarstva Europske unije u smislu bruto društvenog proizvoda i zaposlenosti, pri čemu su upravo obalna područja Europske unije izrazito tražena odredišta kako za europske, tako i za međunarodne putnike. Vrlo često, a posebno tijekom ljetnih mjeseci izražen je pritisak koji rekreacijska plovila vrše na morski okoliš. Povećana prometna potražnja po pojedinim zonama na obali često dovodi do prometnog zagušenja i pratećih negativnih posljedica, pri čemu se pretjeranim iskorištavanjem obale u prirodnom, ali i prometnom smislu narušava atraktivnost određene destinacije što je i primarni razlog zbog kojih su nautičari i odabrali određenu destinaciju. S druge pak strane, neujednačeni načini statističkog praćenja, nedostatak statističkih informacija o ukupnoj populaciji koja ostvaruje putovanja nautičkim plovilima između luka, kao i činjenica da rekreacijska plovila nisu obvezna imati AIS uređaj dodatno otežavaju mogućnost utvrđivanja dinamike kretanja plovila između luka, odnosno utvrđivanja prometnog toka plovila. Kako bi se pokušao riješiti identificirani problem, koristeći se metodologijom prometnog modeliranja te adaptacijom klasičnih metoda prometnog modeliranja ovim doktorskim radom razvijen je prometni model kojim je moguće prije svega utvrditi prijevoznu potražnju u nautičkom turizmu, identificirati zone privlačenja i generiranja putovanja te u konačnici utvrditi prometne rute i količine prometnih tokova za plovila u nautičkom turizmu. Za korak koji uključuje generiranje putovanja, radom su razvijene funkcije za proračun produkcije i atrakcije putovanja, pri čemu se produkcija inicijalnih putovanja izvodi na temelju kreirane regresijske jednadžbe, a kreirane funkcije atrakcije razlikuju se u ovisnosti o vrsti putovanja. Distribucija inicijalnih putovanja, kao i putovanja između luka, napravljena je uz pomoć gravitacijskog modela, pri čemu je ključan doprinos ovog rada proračun i validacija kalibracijske konstante unutar gravitacijskog modela. Testiranjem modela na odabranom području interesa te dobivenim rezultatima dokazano je kako je razvijenim prometnim modelom, uspostavljenim matricama prometne potražnje i raspodjelom potražnje prema rutama i prometnim entitetima moguće riješiti ključan problem vezan uz nedostatak zapisa o stvarnim kretanjima plovila u nautičkom turizmu. Dodatna vrijednost modela uključuje razvijenu mogućnost za odvojeno dodjeljivanje putovanja između luka, točnije mogućnost utvrđivanja količine prometa između luka odvojeno za plovila u charteru te vlastita plovila. Nadalje, ovim radom istaknuti su i ekološki deskriptori u kontekstu nautičkog turizma te je predložen metodološki okvir za penalizaciju pojedinih morskih područja u skladu s kategorijom zaštite. U ovom kontekstu model predstavlja osnovnu bazu koja može poslužiti kao početni alat za upravljanje prometnim opterećenjem pojedinih makro i mikro plovnih područja, pri čemu se dobiveni rezultati mogu koristiti kod planiranja i optimizacije u kontekstu identifikacije vršnih opterećenja u prometnom i ekološkom smislu. Rezultati dobiveni ovim modelom široko su primjenjivi, a mogu služiti i kao potpora u odlučivanju svim dionicima u sektoru nautičkog turizma.Coastal and maritime tourism is the largest sector of the European Union's blue economy in terms of gross domestic product and employment, with the European Union's coastal areas being a highly desirable destination for both European and international travelers. Very often, especially in the summer months, recreational vessels are observed to have a major impact on the marine environment. More specifically, the increased traffic demand in certain coastal areas very often leads to traffic congestion and the associated negative consequences, whereby the excessive use of the coast in the natural, but also in the traffic sense, impairs the attractiveness of a particular destination, which was also the main reason why sailors chose a particular destination. On the other hand, the inconsistent methods of statistical monitoring, the lack of statistical information on the total population traveling by vessels between ports and the fact that recreational vessels are not obliged to have an AIS device make it difficult to determine the dynamics of vessel movements between ports, i.e. the vessel traffic flow. To solve the identified problem, by using the methodology of transport modeling and adapting classical methods of transport modelling, this dissertation developed a transport model that can be used to determine traffic demand in nautical tourism, to identify zones of attraction and generation of trips, and finally to determine traffic routes and traffic flows for vessels in nautical tourism. For the step involving the generation of trips, production and attraction functions were developed as part of the work, whereby the production of the initial trips is based on the regression equation created and the attraction functions created differ depending on the type of trip. The distribution of initial trips and port-to-port trips was done using a gravity model, with the main contribution of this thesis being the calculation and validation of the calibration constant within the gravity model. An additional value of the model is the developed possibility of separate trip assignment between ports, more precisely the possibility to determine the traffic volume between ports separately for charter vessels and privately owned vessels. By testing the model in the selected area of interest, the results obtained have proven that the developed transport model is able to solve the main problem related to the lack of records of actual vessel movements in nautical tourism through the generated traffic demand matrices and the distribution of demand among routes and traffic entities. In addition, this paper also highlighted environmental descriptors related to nautical tourism and proposed a methodological framework for sanctioning certain marine areas according to their protection category. In this context, the model represents a fundamental basis that can serve as an initial tool for the traffic flow management of individual macro and micro sailing areas. The results obtained can be used for planning and optimization in the context of determining traffic and ecological peaks. The present results are applicable and can serve as a decision-making aid for all stakeholders in the field of nautical tourism
Interpretable Machine Learning: A Case Study on Predicting Fuel Consumption in VLGC Ship Propulsion
No full textThe integration of machine learning (ML) in marine engineering has been increasingly subjected to stringent regulatory scrutiny. While environmental regulations aim to reduce harmful emissions and energy consumption, there is also a growing demand for the interpretability of ML models to ensure their reliability and adherence to safety standards. This research highlights the need to develop models that are both transparent and comprehensible to domain experts and regulatory bodies. This paper underscores the importance of transparency in machine learning through a use case involving a VLGC ship two-stroke propulsion engine. By adhering to the CRISP-DM standard, we fostered close collaboration between marine engineers and machine learning experts to circumvent the common pitfalls of automated ML. The methodology included comprehensive data exploration, cleaning, and verification, followed by feature selection and training of linear regression and decision tree models that are not only transparent but also highly interpretable. The linear model achieved an RMSE of 23.16 and an MRAE of 14.7%, while the accuracy of decision trees ranged between 96.4% and 97.69%. This study demonstrates that machine learning models for predicting propulsion engine fuel consumption can be interpretable, adhering to regulatory requirements, while still achieving adequate predictive performance
Multifunctional Analysis of the State Administration Bodies of the Republic of Croatia in the Implementation of Control and Protection of the Rights and Interests in the East Coast of the Adriatic Sea
No full textThe paper has conducted a structural analysis of the relevant state administration bodies of the Republic of Croatia regarding the operational efficiency of implementing the protection of rights and interests in the marine and underwater areas of the semi-enclosed Adriatic Sea, where the respective coastal state (the Republic of Croatia) exercises jurisdiction in accordance with international law. A comprehensive overview of all components of the system, as well as some sensors of the state administration bodies of the Republic of Croatia involved in the implementation of control, monitoring, and protection of rights and interests in the Adriatic Sea – the eastern part, has been synthesized. An analysis of maritime traffic security was conducted. Data on ship, cargo, and passenger traffic in the seaports of the respective coastal state were collected. The analysis covered a four-year period between 2019 and 2022
Analysis of the capacity and operation of nautical tourism ports and development tendencies
No full textLuke nautičkog turizma ključni su element razvoja nautičkog turizma pružajući nautičarima mogućnost boravka u određenoj destinaciji što ukazuje na potrebu njihovog analiziranja. U radu se kao uvod u razradu teme daju teorijske odrednice luka nautičkog turizma. Pri tome se ukazuje na pojam i značajke luka nautičkog turizma, njihovo razvrstavanje i kategorizacija u skladu sa zakonskom regulativom u Republici Hrvatskoj. Pod lukama nautičkog turizma u kontekstu ovog rada podrazumijevaju se luke posebne namjene koje se koriste za prihvat i smještaj plovila, a opremljene su u svrhu pružanja usluga korisnicima i plovilima. Poseban fokus u radu dan je analizi kapaciteta i poslovanja luka nautičkog turizma u Republici Hrvatskoj. Kapaciteti luka nautičkog turizma promatraju se korištenjem kvantitativnih podataka broja vezova i broja plovila te se podaci uspoređuju s drugim zemljama članicama Europske unije kako bi se došlo do zaključka o razini razvijenosti prihvatnih kapaciteta i konkurentnosti hrvatskog nautičkog turizma. Osim kvantitativnih pokazatelja razvijenosti luka nautičkog turizma u Republici Hrvatskoj, analiziraju se usluge koje luke nautičkog turizma nude, te poslovni rezultati luka nautičkog turizma (prihodi i rashodi). Na temelju provedene analize i trendova prisutnih u na tržištu nautičkog turizma, u radu se istražuju tendencije budućeg razvoja nautičkog turizma u Republici Hrvatskoj. Pri tome se naglasak stavlja na primjenu načela održivog razvoja kao kompromisa između potreba očuvanja prirodnog prostora i potrebe za gospodarskim razvojem, što podrazumijeva utvrđivanje nosivog kapaciteta prostora i određivanja granice rasta novih prihvatnih kapaciteta.Nautical tourism ports are a key element in the development of nautical tourism, as they offer sailors the opportunity to stay in a particular place, which points to the need to analyse them. In the paper, as an introduction to the elaboration of the topic, the theoretical determinants of nautical tourism ports are mentioned. At the same time, the concept and characteristics of nautical tourism ports, their classification and categorisation in accordance with the legal provisions in the Republic of Croatia are given. In this work, nautical tourism ports are understood as special ports used for receiving and accommodating vessels and equipped to provide services for users and vessels. The main focus today is on the analysis of the capacity and operation of nautical tourism ports in the Republic of Croatia. The capacity of ports for nautical tourism is monitored using quantitative data on the number of berths and the number of vessels, and compared with other EU Member States in order to make a statement about the level of development of reception capacity and the competitiveness of Croatian nautical tourism. In addition to the quantitative indicators of the development of nautical tourism ports in the Republic of Croatia, the services offered by nautical tourism ports and the business results of nautical tourism ports (revenues and expenses) are analysed. Based on the analysis and trends on the nautical tourism market, the tendencies of the future development of nautical tourism in the Republic of Croatia are examined. Emphasis is placed on the application of the principles of sustainable development as a compromise between the need to preserve natural space and the need for economic development, which implies the determination of the carrying capacity of space and the definition of the growth limit for new reception capacities
Cooperative urban traffic systems
No full textKooperativni sustavi u urbanom prometu predstavljaju napredne tehnološke pristupe koji povezuju vozila, prometnu infrastrukturu i informacijske tehnologije radi poboljšanja mobilnosti, sigurnosti i učinkovitosti u urbanim sredinama kako bi se unaprijedila protočnost prometa, smanjile gužve, poboljšala sigurnost i potaknula održivost u gradskim okruženjima. Kooperativni sustavi također podržavaju održive opcije prijevoza, kao što su dijeljenje vožnji i javni prijevoz, smanjujući emisije i potrebu za osobnim automobilima. Integracija autonomnih vozila i tehnologije interneta stvari (IoT) otvara put prema prometnoj revoluciji, pružajući priliku za stvaranje pametnih i učinkovitih gradova budućnosti. Ključni elementi uključuju razmjenu informacija o brzinama, gužvama, prometnim signalima i drugim prometnim uvjetima. Kooperativni sustavi predstavljaju ključni korak prema pametnim i održivim urbanim prometnim rješenjima, poboljšavajući mobilnost, smanjujući zagađenje i potičući razvoj inovativnih tehnologija.Cooperative systems in urban transport represent advanced technological approaches that connect vehicles, transport infrastructure and information technologies to improve mobility, safety and efficiency in urban environments to improve traffic flow, reduce traffic jams, improve safety and promote sustainability in urban environments. Cooperative systems also support sustainable transportation options, such as ride-sharing and public transportation, reducing emissions and the need for personal cars. The integration of autonomous vehicles and Internet of Things (IoT) technology is paving the way for a transportation revolution, providing an opportunity to create smart and efficient cities of the future. Key elements include sharing information about speeds, jams, traffic signals and other traffic conditions. Cooperative systems represent a key step towards smart and sustainable urban transport solutions, improving mobility, reducing pollution and encouraging the development of innovative technologies
PUP_ENGRI_HRZZ_UIP-2019-04-1576_49_60
No full textPlan upravljanja istraživačkim podacima za projekt ENGRI (ENGLESKE RIJEČI U HRVATSKOME JEZIKU: IDENTIFIKACIJA, AFEKTIVNO-SEMANTIČKO NORMIRANJE I ISPITIVANJE KOGNITIVNE OBRADE BIHEVIORALNIM I NEUROZNANSTVENIM METODAMA), financiran od strane Hrvatske zaklade za znanost, za 5. projektno razdoblje (49-60)
Systems for abandoning large passenger ships
No full textNa svim brodovima je najbitnija sigurnost, a pogotovo na putničkim brodovima zbog
putnika na tim brodovima. Iz tog razloga ulaže se veliki trud i novac u sigurnosnu opremu
na putničkim brodovima. U ovome završnom radu navedeni su sustavi za napuštanje velikih
putničkih brodova i opisana njihova funkcija. Sustavi za napuštanje velikih putničkih
brodova su ključni u operacijama napuštanja broda radi olakšanog i brzog napuštanja broda.
Za uspješno napuštanje broda potrebna je uvježbana posada i dobro očuvana oprema za
spašavanje.Safety is the most important thing on all ships, especially on passenger ships because of the passengers on those ships. For this reason, a lot of effort and money is invested in safety equipment on passenger ships. In this final paper, the systems for abandoning large passenger ships are listed and their function is described. Abandonment systems for large passenger ships are essential in abandonment operations for easy and quick abandonment of the ship. Successful abandonment requires a trained crew and well-preserved rescue equipment
Smart ports
No full textKroz povijest pa do današnjeg dana luke su važno središte za prihvat, transakciju,
prijevoz i skladištenje robe i tereta. Veliki kapaciteti tereta i brobova, velika gustoća prometa
te briga za okoliš glavni su razlozi luka da usvoje nove tehnologije i postanu pametne luke.
Pametne luke koriste tehnologije koje pomažu kod optimizacije poslovanja, smanjenja gužvi
te pomoću automatiziranih terminala povećavaju sigurnost i smanjuju negativan utjecaj na
okoliš. Pametne luke su isto tako i konkurentnije na tržištu što im pomaže kod daljnjeg
razvoja te prate svijetske trendove i primjenjuju politike održivog razvoja.Throughout history and today, ports have been crucial hubs for receiving, transacting,
transporting, and storing goods and cargo. The large capacities of cargo and ships, high
traffic density, and environmental concerns are the main reasons for ports to adopt new
technologies and become smart. Smart ports utilize technologies that help optimize
operations, reduce congestion, and increase safety through automated terminals while
minimizing negative environmental impacts. Smart ports are also more competitive in the
market, which aids in their further development, and they follow global trends and
implement sustainable development policies
Dry stack boat storage system : a sustainability and efficiency approach
No full textOvaj diplomski rad istražuje skladištenje plovila u suhim marinama, s posebnim fokusom na pristup održivosti i operativnoj učinkovitosti te regalno skladištenje. Istraživanjem su proučeni i definirani inovativni pristupi koji poboljšavaju održivost i učinkovitost operacija u suhim marinama. Inovativna rješenja, poput regalnog skladištenja plovila, pokazala su se ključnima za povećanje operativne učinkovitosti jer omogućavaju optimalno korištenje prostora i smanjuju troškove održavanja. Rad obuhvaća planiranje suhih marina, inovativna rješenja za skladištenje plovila poput regalnih skladišta, te SWOT analizu koja identificira snage, slabosti, prilike i prijetnje skladištenja plovila u suhim marinama s prikazanim primjerima dobre prakse iz industrije. Snage ponajviše ukazuju na to da suhe marine smanjuju troškove održavanja i povećavaju sigurnost dok slabosti ukazuju na visoka početna ulaganja no dugoročnu isplativost. Cilj rada je pružiti sveobuhvatan pregled kako suhe marine mogu postati model održivog razvoja u nautičkom turizmu, uz maksimizaciju operativne učinkovitosti.This master thesis covers the storage of vessels in dry marinas, with a particular focus on the approach to sustainability and operational efficiency, and dry rack storage. The research studied and defined innovative approaches that improve the sustainability and efficiency of operations in dry marinas. Innovative solutions, such as dry stack boat storage system, have proven to be key in increasing operational efficiency by optimizing space usage and reducing maintenance costs. Thesis includes dry marina planning, innovative solutions for vessel storage such as dry stacks, and a SWOT analysis that identifies the strengths, weaknesses, opportunities and threats of vessel storage in dry marinas with examples of good practice from the industry. The strengths mainly indicate that dry marinas reduce maintenance costs and enhance security, while the weaknesses point to high initial investments but long-term profitability. Purpose of the thesis is to provide a comprehensive overview of how dry marinas can become a model of sustainable development in nautical tourism, while maximizing operational efficiency