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Marine hydraulic ramp
No full textRasprostranjenost hidraulike u današnjem vremenu u raznim područjima od alatnih strojeva pa sve do brodova, pogotovo važnost koju ima automatizacija potrebno je poznavanje hidraulike. Primjena automatizacije gdje hidraulični uređaji automatskim putem mogu biti isprogramirani da obavljaju funkciju bez prisutnosti operatera osim kod pokretanja, zaustavljanja i održavanja strojeva, uređaja i njenih komponenti gdje isti operater vrši regulaciju sustava. Jedan primjer hidraulike kod brodova je „brodska hidraulična rampa na RO-RO brodovima gdje će dalje u radu biti opisana konstrukcija i funkcija brodske rampe. RO-RO brodovi koji imaju mogućnost rampi na pramcu, krmi i boku za ukrcaj tereta na kotačima su najefikasnijih zbog te lakoće ukrcaja/iskrcaja. Rad se sastoji od uvoda, pet poglavlja i zaključka, kao i dopunska pod poglavlja, popis korištene literature, elektronskih izvora i popis slika.Prevalence of hydraulics in today´s times in various fields, from machinery tools to ships, especially an importance which automatization offers with knowledge of hydraulics. The use of automatization where hydraulic machinery through automatic means can be programmed to solve tasks without presence of the operator except in starting, stopping and maintenance of machines, devices and their components where same operator performs system regulation. One example of hydraulics in ships is the „ship hydraulic ramp on RO-RO vessels, where the construction and function of the ship ramp will be described further in this work. RO-RO vessels, which have ramps at the bow, stern, and side for loading wheeled cargo, are the most efficient because of ease of loading/unloading. The work consists of an introduction, five chapters and the conclussion, as well as supplementary subchapters, a list of references, electronic sources, and a list of figures
Primjena računalnog vida za detekciju podvodnog otpada
No full textThis master’s thesis explores the application of computer vision and Deep Learning (DL) for the detection of underwater litter, which represents a growing global environmental concern. Traditional monitoring methods, such as diver-based surveys and the use of Remotely Operated Vehicles (ROVs), are often expensive, time-consuming, and only able to cover relatively small areas. The goal of this thesis is to examine how modern computer vision techniques can support more efficient and scalable approaches to underwater litter detection. The thesis provides an overview of key topics including data acquisition technologies, environmental and technical challenges, underwater image preprocessing and enhancement methods, as well as the most commonly used object detection models like You Only Look Once (YOLO), Faster Region-based Convolutional Neural Network (Faster R-CNN), and Single Shot MultiBox Detector (SSD). Special attention is given to the analysis of available datasets, their limitations, and how synthetic data and augmentation techniques can improve training and model performance. Practical applications and case studies are also presented, where computer vision models have been integrated with platforms such as ROVs, Autonomous Underwater Vehicles (AUVs), Unmanned Aerial Vehicles (UAVs), and surface robots. In the final part, it discusses potential future developments, including semi-supervised learning (SSL), transformer-based architectures, integration with autonomous systems, and multi-modal sensing strategies. The overall objective is to highlight the potential of computer vision as a valuable tool in addressing the challenge of underwater litter monitoring and contributing to the protection of marine environments.Ovaj diplomski rad istražuje primjenu računalnog vida i dubokog učenja (engl. Deep Learning, DL) za detekciju podvodnog otpada, koji predstavlja sve veći globalni ekološki problem. Tradicionalne metode nadzora, poput ronilačkih pregleda i korištenja daljinski upravljanih podvodnih vozila (engl. Remotely Operated Vehicle, ROV), često su skupe, vremenski zahtjevne i mogu pokriti samo relativno mala područja. Cilj ovog rada je ispitati kako moderne tehnike računalnog vida mogu podržati učinkovitije i skalabilnije pristupe detekciji podvodnog otpada. Rad pruža pregled ključnih tema, uključujući tehnologije prikupljanja podataka, okolišne i tehničke izazove, metode predobrade i poboljšanja podvodnih slika, kao i najčešće korištene modele za detekciju objekata poput poput You Only Look Once (YOLO), Faster Region-based Convolutional Neural Network (Faster R-CNN) i Single Shot MultiBox Detector (SSD). Posebna pažnja posvećena je analizi dostupnih skupova podataka, njihovim ograničenjima i načinima na koje sintetički podaci i tehnike augmentacije mogu poboljšati treniranje i performanse modela. Također su predstavljene praktične primjene i studije slučaja u kojima su modeli računalnog vida integrirani s platformama poput ROV-ova, autonomnih podvodnih vozila (engl. Autonomous Underwater Vehicle, AUV), bespilotnih letjelica (engl. Unmanned Aerial Vehicle, UAV) i robotskih površinskih sustava. U završnom dijelu raspravlja se o potencijalnim budućim razvojnim smjerovima, uključujući polunadzirano učenje, arhitekture temeljene na transformerima, integraciju s autonomnim sustavima i višemodalne senzorske strategije. Sveukupni cilj rada je istaknuti potencijal računalnog vida kao vrijednog alata za rješavanje izazova praćenja podvodnog otpada i doprinos očuvanju morskog okoliša
Comparative analysis of the protection of the underwater part of the ship's hull by sacrificial anodes and impressed current
No full textKorozija podvodnog dijela broda čest je problem koji može uzrokovati velika oštećenja i povećati troškove održavanja. Kako bi se brodovi zaštitili, koriste se različite metode katodne zaštite, a najčešće su to sustavi sa žrtvovanim anodama i sustavi s narinutom strujom. U ovom radu analiziraju se obje metode i uspoređuju prema učinkovitosti, cijeni, održavanju i primjeni na različitim vrstama brodova. Također se razmatraju njihovi utjecaji na okoliš i tehnički zahtjevi koje traže. Na temelju prikupljenih podataka i primjera iz prakse, daju se preporuke koja je metoda prikladnija za određene uvjete. Cilj rada je pružiti jasan pregled prednosti i nedostataka obje metode zaštite te pomoći u odabiru optimalnog rješenja.Corrosion of the underwater part of a ship is a common issue that can lead to serious damage and increased maintenance costs. To protect vessels, different methods of cathodic protection are used, with sacrificial anodes and impressed current systems being the most common. This paper analyzes and compares these two methods in terms of effectiveness, cost, maintenance, and their application on different types of ships. Environmental impact and technical requirements of each system are also considered. Based on collected data and real-life examples, recommendations are provided on which method is more suitable for specific conditions. The goal of this paper is to give a clear overview of the advantages and disadvantages of both protection methods and assist in choosing the optimal solution
Nondestructive testing of a pressure vessel
No full textCilj ovog diplomskog rada je određivanje stanja i daljnje upotrebljivosti zadane posude pod tlakom upotrebljavajući dostupne nerazorne metode ispitivanja materijala. U teoretskom dijelu rada opisani su osnovni dijelovi posude pod tlakom, pravilnici o ispitivanju posuda pod tlakom, vrste nerazornih metoda ispitivanja posuda pod tlakom, opisani su postupci vizualnog i ultrazvučnog nerazornog ispitivanja te ispitivanja tlakom jer će se oni primijeniti u eksperimentalnom dijelu. Također opisana su i moguća oštećenja posuda pod tlakom i uzroci njihovog nastajanja. U eksperimentalnom dijelu navedeni su opći podaci o posudi pod tlakom, dostupne nerazorne metode ispitivanja materijala koje su se primijenile poput vizualnog i ultrazvučnog ispitivanja, navedeni su svi uređaji i oprema koja se koristila prilikom ispitivanja, opisan i dokumentiran je sam tijek ispitivanja, prikazani su rezultati na osnovu kojih je donijeta odluka o daljnjoj upotrebljivosti posude pod tlakom.The aim of this thesis is to determine the condition and further usability of a given pressure vessel using available non-destructive material testing methods. In the theoretical part of the work, the basic parts of the pressure vessel are described, the regulations on the testing of pressure vessels, the types of non-destructive testing methods of pressure vessels, the procedures of visual and ultrasonic non-destructive testing along with the pressure test are described because they will be applied in the experimental part. Possible damage to pressure vessels and the causes of their occurrence are also described. In the experimental part, general information about the pressure vessel is listed, available non-destructive material testing methods that were applied, such as visual and ultrasonic testing, all the devices and equipment used during the test are listed, the test process itself is described and documented, and the results are presented on the basis of which a decision was made on the further usability of the pressure vessel
Potential cyber threats to certain systems on board ships
No full textRad objasnjava potencijalne prijetnje u pomorskoj industriji kroz sigurnosne izazove u vezi s informacijskim sustavima. S obzirom na razinu razvoja digitalizacije i automatizacije brodskih operacija, naglasena je potreba za ucinkovitom zastitom od kibernetickih napada da bi se umanjila mogucnost ugrozavanja sigurnosti. Rad se temelji na analizi kibernetickih napada i ranjivosti sustava kao sto su Sustav za automatsku identifikaciju, Globalni sustav za odredivanje polozaja i Informacijski sustav i prikaz elektronickih karata. Cilj je povecati svijest o vaznosti sigurnosti u pomorskom sektoru i na temelju toga razviti strategije zastite informacijskih sustava na moru.The paper explains potential threats in the maritime industry through security challenges related to information systems. Given the level of development of digitalization and automation in ship operations, the need for effective protection against cyberattacks is emphasized in order to reduce the risk of compromising security. The paper is based on the analysis of cyberattacks, vulnerabilities in systems such as Automatic Identification System, Global Positioning System, and Electronic Chart Display and Information System. The goal is to raise awareness about the importance of security in the maritime sector and, based on this, develop strategies for protecting information systems at sea
Safety margin in ECDIS
No full textU ovom završnom radu se obrađuje sigurnosna margina Informacijskog sustava i prikaza elektroničkih karata (engl. Electronic Chart Display and Information System – ECDIS). Glavni cilj rada je razjasniti značajke sigurnosne margine ECDIS sustava koje su od izuzetne važnosti za pravovremeno otkrivanje opasnosti i minimaliziranje ljudskih pogrešaka u navigaciji. Sigurnosna margina može se podijeliti na horizontalnu i vertikalnu komponentu. U radu će naglasak biti na primjeni i postavljanju sigurnosnih margina. U horizontalnom smislu razjasnit će se postavke kako bi brod plovio na sigurnoj udaljenosti od navigacijskih opasnosti, dok će se u vertikalnom smislu, razjasniti postavljanje parametra vezanih za sigurnosnu dubinu. Analizirat će se i određene nezgode koje su nastale upravo zbog nepravilnog korištenja i postavljanja sigurnosnih parametara vezanih za dubinu zbog kojih je došlo do nasukavanja brodova.This thesis addresses the safety margin of the Electronic Chart Display and Information System (ECDIS). The main goal of the thesis is to clarify the safety margins of the ECDIS system, which are crucial for the timely detection of hazards and minimizing
human errors in navigation. Safety margin can be divided into horizontal and vertical component. The emphasis of the thesis will be on the application and setting of safety margin. In the horizontal sense, it will explain the settings required for the vessel to navigate at a safe distance from navigational hazards, while in the vertical sense, it will clarify the parameters related to safety depth settings. The thesis will also analyze accidents that occurred due to improper configuration of safety margins, which led to the grounding of vessels
Abandoned, lost or otherwise discharged fishing gear
No full textNapuštena, izgubljena ili odbačena ribolovna oprema (ALDFG) predstavlja ozbiljan problem za morski okoliš, sigurnost plovidbe i održivost ribarstva. Ova oprema često ostaje u moru zbog loših vremenskih uvjeta, tehničkih kvarova, navigacijskih pogrešaka ili namjernog odbacivanja. Najveći problem predstavlja tzv. fantomski ribolov – proces u kojem izgubljena oprema nastavlja hvatati morske organizme, uključujući zaštićene i neciljane vrste, uzrokujući ekološku i ekonomsku štetu. Rad analizira uzroke ALDFG-a, njegov utjecaj na okoliš, pravni okvir i moguće mjere prevencije i ublažavanja. Poseban naglasak stavljen je na važnost označavanja opreme, biorazgradivih materijala i sustava povrata alata kako bi se spriječila daljnja degradacija morskih ekosustava.Abandoned, lost or otherwise discarded fishing gear (ALDFG) represents a serious threat to the marine environment, navigational safety, and the sustainability of fisheries. This gear often remains in the sea due to bad weather conditions, technical failures, navigational errors, or intentional disposal. A major issue is ghost fishing – a process in which lost gear continues to catch marine organisms, including protected and non-target species, causing both ecological and economic damage. This thesis analyzes the causes of ALDFG, its environmental impact, the legal framework, and possible prevention and mitigation measures. Special attention is given to gear marking, biodegradable materials, and retrieval systems to prevent further degradation of marine ecosystems
World shipping fleet and shipbuilding
No full textNeminovna je važnost stanja svjetske trgovačke flote i njenog utjecaja na globalnu
ekonomiju. Ova pitanja stoga se ne tiču samo stručnjaka, već i svih ljudi pute kreiranja
svakodnevnih tržišnih cijena kao odgovora na stanje u pomorskom i vozarinskom tržištu. Ova
tržišta zato je važno pažljivo analizirati i pratiti trendove i kretanja kako bi se osigurala
održivost pomorskog transporta. Cilj ovog diplomskog rada stoga je dati pregled aktualnog
stanja svjetske pomorske trgovine i svjetske flote te problema koji ih snalaze. Stanje svjetske
flote direktno je povezano s globalnom industrijom brodogradnje. Aktualnosti u brodogradnji
u najvećoj su mjeri povezane s pokušajima ostvarenja što je više moguće održivijih brodova u
smislu zaštite okoliša. Takvi novi brodovi sada predstavljaju napretke u svjetskoj floti i imaju
mogućnost ostvarenja povoljnijeg položaja i benefita na svjetskom pomorskom tržištu. Stoga
je pomak prema zelenoj tranziciji jedan od glavnih koraka prema ostvarenju stabilnog
pomorskog brodarstva i svjetske flote kojemu je potrebno težiti.The importance of the world's merchant fleet and its impact on the global economy is
inevitable. These questions therefore concern not only experts, but also all people through the
creation of daily market prices in response to the state of the maritime and freight markets.
Because of that it is important to carefully analyze these markets and monitor trends and
developments in order to ensure the sustainability of maritime transport. The aim of this thesis
is to provide an overview of the current state of world maritime trade, the world fleet and the
problems that they face. The state of the world fleet is directly related to the global shipbuilding
industry. Current events in shipbuilding are largely related to attempts to create as many
sustainable ships as possible in terms of environmental protection. Such new ships now
represent advances in the world fleet and have the possibility of achieving a more favorable
position and benefits in the global maritime market. Therefore, the move towards a green
transition is one of the main steps towards achieving a stable maritime shipping and world fleet
that we need to strive for
The importance of teamwork organization in the prevention of accidents at sea
No full textUčinkovit timski rad ključan je u sprječavanju nesreća na moru, jer promiče bolju komunikaciju, koordinaciju i donošenje odluka. Nedostatak ovih elemenata bio je faktor koji je doprinio velikim pomorskim katastrofama kao što su Exxon Valdez, Costa Concordia i MV Herald of Free Enterprise. Primjenom praksi kao što su obuka za upravljanje resursima posade i sustavi upravljanja sigurnošću, sigurnosne performanse posade mogu se značajno poboljšati. Standardizirani postupci, stalna obuka, simulacije i poticaji za kontinuirano učenje igraju ključnu ulogu u održavanju visokih sigurnosnih standarda i operativne učinkovitosti na brodovima. Slijedeći ove strategije, rizik od nesreća može se smanjiti, osiguravajući sigurnu i uspješnu plovidbu.Effective teamwork is crucial in preventing accidents at sea, as it promotes better communication, coordination and decision-making. The lack of these elements has been a contributing factor to major maritime disasters such as the Exxon Valdez, Costa Concordia and the MV Herald of Free Enterprise. By implementing practices such as crew resource management training and safety management systems, crew safety performance can be significantly improved. Standardized procedures, ongoing training, simulations and incentives for continuous learning play a key role in maintaining high safety standards and operational efficiency on board ships. By following these strategies, the risk of accidents can be reduced, ensuring safe and successful navigation
Environmental aspects of sea pollution with oils from ships
No full textU ovom radu se objašnjavaju ekološki aspekti onečišćenja mora uljem ujedno se tumači i sastav ulja i njegove glavne karakteristike. Onečišćenje mora uljem predstavlja ozbiljan ekološki problem koji nastaje kao rezultat nekontroliranog ispuštanja nafte ili naftnih derivata u morski okoliš. Ovakva onečišćenja mogu imati ozbiljne posljedice na morski ekosustav, ugrožavajući morske organizme, ptice, biljke i ukupnu biološku raznolikost. Opisuju se i navode glavne međunarodne organizacije i propisi u slučaju onečišćenja mora uljem. Temeljna tema diplomskog rada je sama konstrukcija tankera koji mora biti građen po svim zakonima i pravilima konvencija i klasifikacijskim društava koje se brinu o sigurnosti u plovidbi i sprječavanju onečišćenja mora.This work explains the ecological aspects of oil pollution in the sea while also interpreting the composition of oil and its main characteristics. Oil pollution in the sea represents a serious environmental problem that arises as a result of uncontrolled release of oil or oil derivatives into the marine environment. Such pollution can have severe consequences on the marine ecosystem, endangering marine organisms, birds, plants, and overall biodiversity. The main international organizations and regulations in the case of oil pollution in the sea are described and referenced. The central theme of the graduation thesis is the construction of oil tankers, which must be built in accordance with all laws, conventions, and classification societies that ensure safety in navigation and prevention of sea pollution