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Sea Beaches Near Coal Mine Water: Emphasis on Selenium
No full textGroundwater and surface streams draining abandoned seleniferous coal mines and ash piles are among
major causes of environmental exposure to selenium (Se). One such scenario is located on the eastern
Adriatic coastline of the Istrian Peninsula (western Croatia), where the legacy of the former Raša
coal industry is reflected in elevated levels of Se in key environmental media and biota. Selenium
in animals and humans is an essential nutrient that has a quite narrow window between deficiency
and toxicity. Geology exerts a fundamental control on the environmental Se concentrations, but
aquatic contamination with Se has gained widespread concerns because Se is derived from the largest
production activities, such as coal-fired power plants, oil refining, mining, and agriculture. Hence,
Se was periodically found to be the cause of the devastating impacts to local ecosystems. Therefore,
the objectives of this paper are as follows: 1) to provide a brief overview of coal-derived selenium
in the environment, 2) to present basic principles of selenium geochemistry entailing environmental
implications, and 3) to show variability of Se levels in ambient water samples collected by authorities
of the coal-fired power plant Plomin during the period 2013-2023 for the monitoring purposes. This
paper warrants further research of the Raša coal area which is close to beaches very popular among
tourists and locals
Application of sliding and rolling bearings in marine system
No full textLežajevi su ključni strojni elementi koji omogućuju relativno gibanje dijelova uz minimalno trenje, podupiru osovine i prenose opterećenja. Dijele se na klizne i valjne. Klizni ležajevi koriste klizni kontakt i pogodni su za sustave s visokim opterećenjima i tihim radom, dok valjni smanjuju trenje kotrljajućim elementima, omogućuju veću energetsku učinkovitost pri višim brzinama. Njihova primjena ovisi o radnoj brzini, vrsti opterećenja i zahtjevima održavanja. U pomorstvu su ključni za pouzdan rad brodskih sustava, a njihov kvar može uzrokovati ozbiljne probleme, uključujući povećano trenje, pregrijavanje i oštećenja mehaničkih sklopova, što dovodi do zastoja i povećanja troškova održavanja.Bearings are essential machine elements that enable relative motion between parts with minimal friction, support shafts, and transmit loads. They are classified as sliding or rolling bearings. Sliding bearings use direct surface contact and are ideal for high-load, low-noise applications, while rolling bearings reduce friction with rolling elements, improving energy efficiency at higher speeds. Their selection depends on operational speed, load type, and maintenance requirements. In maritime applications, bearing ensure reliable operation of ship systems, and their failure can lead to friction increase, overheating, and mechanical damage, causing downtime and high maintenance cost
Economic justification of sailing tourism
No full textOvaj rad obrađuje jedriličarski turizam kao specifičan i sve značajniji segment nautičkog
turizma u Republici Hrvatskoj, s posebnim naglaskom na njegovo gospodarsko iskorištavanje.
Analiziran je zakonodavni i tehnički okvir registracije jedrilica za gospodarske svrhe,
uključujući proces izrade potrebne dokumentacije, tehničke preglede te proračun stabiliteta s
jedrima. Posebna pažnja posvećena je tržištu Istre kao jednoj od najrazvijenijih regija za
nautički turizam te je obrađen konkretan primjer poslovanja jedrilice Nelson 46. U radu su
također predstavljeni najnoviji statistički podaci o prihodima luka nautičkog turizma,
popunjenosti kapaciteta i strukturi plovila u tranzitu. Rezultati ukazuju na stabilan rast prihoda
i povećanje interesa za jedriličarskim aktivnostima, pri čemu se naglašava potreba za daljnjim
ulaganjem u infrastrukturu, modernizaciju usluga i održivi razvoj sektora. Jedriličarski turizam
pokazuje visoki gospodarski potencijal te značajno doprinosi produljenju turističke sezone,
zapošljavanju i jačanju lokalnih ekonomija.This paper explores sailing tourism as a specific and increasingly significant segment of
nautical tourism in the Republic of Croatia, with a particular emphasis on its economic
utilization. The legislative and technical framework for registering sailboats for commercial
purposes is analyzed, including the process of preparing the necessary documentation,
conducting technical inspections, and calculating sail stability. Special attention is given to the
market of the Istrian region, one of the most developed areas for nautical tourism, with a case
study of the business operations of the sailboat Nelson 46. The paper also presents the latest
statistical data on the revenues of nautical tourism ports, berth occupancy rates, and the structure
of vessels in transit. The results indicate a stable increase in revenue and growing interest in
sailing activities, highlighting the need for further investment in infrastructure, service
modernization, and sustainable sector development. Sailing tourism demonstrates high
economic potential and significantly contributes to the extension of the tourist season,
employment, and the strengthening of local economies
Maritime bulk cargo market
No full textOvaj rad istražuje pomorsko tržište rasutog tereta, analizirajući ključne ekonomske, tehničke i
operativne aspekte s posebnim naglaskom na 2023. godinu. U radu su objašnjeni temelji
sezonalnosti i cikličnosti tržišta, karakteristike brodova te globalni tokovi sirovina poput
ugljena, željezne rude i žitarica. Posebna pažnja posvećena je poslovanju vodećih brodarskih
kompanija i njihovoj prilagodbi izazovima poput ekoloških standarda i volatilnosti tržišta.
Zaključno, rad naglašava ulogu inovacija, održivosti i strateškog planiranja za budući razvoj
sektora te njegovu otpornost na globalne promjeneThis paper examines the maritime bulk market, analyzing key economic, technical and
operational aspects with a particular focus on the year 2023. The paper explains the basis of
seasonality and cyclicality of the market, the characteristics of ships and the global flows of
raw materials such as coal, iron ore and grain. Special attention is paid to the operations of
leading shipping companies and their adaptation to challenges such as environmental
standards and market volatility. In conclusion, the paper emphasizes the role of innovation,
sustainability and strategic planning for the future development of the sector and its resistance
to global changes
Burners on marine boilers
No full textBrodski generatori pare proizvode paru koja se koristi za pogon parnih turbina, pomoćnih uređaja (poput crpki i separatora) te za grijanje različitih sustava na brodu. Oni omogućuju stabilnu i učinkovitu pretvorbu energije iz goriva u toplinsku i mehaničku energiju unutar brodskog energetskog sustava. Gorači brodskih generatora pare ključna su komponenta sustava za proizvodnju pare jer osiguravaju učinkovito izgaranje goriva i stabilan rad generatora pare. Njihov razvoj usko je povezan s napretkom pomorske tehnologije i prilagodbom različitim vrstama goriva, loživog ulja, boil-off plina (BOG) na LNG brodovima te kombiniranog izgaranja ulja i plina.Marine steam generators produce steam that is used to power steam turbines, auxiliary equipment (such as pumps and separators), and for heating various systems on board. They enable stable and efficient conversion of energy from fuel into thermal and mechanical energy within the ship’s power system. Burners in marine steam generators are a key component of the steam production system, ensuring efficient fuel combustion and stable operation of the steam generator. Their development is closely linked to advances in marine technology and adaptation to different types of fuel, including fuel oil, boil-off gas (BOG) on LNG carriers, and combined oil-gas combustion
Risks and risk assessment in crude oil ship-to-ship (STS) transfer operations
No full textOvaj završni rad obrađuje operacije prekrcaja sirove nafte s jednog tankera na drugi (STS – Ship-to-Ship transfer), s naglaskom na prepoznavanje i procjenu rizika povezanih s takvim postupcima. STS operacije predstavljaju važan dio međunarodnog pomorskog prijevoza nafte, ali istovremeno donose određene sigurnosne i okolišne izazove. U radu su analizirani ključni tehnički, organizacijski i ljudski čimbenici koji mogu utjecati na sigurnost tijekom STS operacija, kao i međunarodni propisi i preporučene prakse koje ih reguliraju. Poseban naglasak stavljen je na proces procjene rizika, uključujući analizu mogućih nezgoda, njihovih posljedica te mjera za prevenciju i odgovor. Cilj rada je dati jasan i sveobuhvatan pregled sigurnosnih zahtjeva potrebnih za kvalitetno planiranje i provođenje STS operacija, uz nastojanje da se smanji rizik po ljude, okoliš i brodove.This final thesis explores the operations of crude oil transfer between tankers (STS – Ship-to-Ship transfer), with a particular focus on identifying and assessing the risks associated with this process. STS operations represent a significant part of international maritime oil transportation but also pose various safety and environmental challenges. The paper analyzes the key technical, organizational, and human risk factors, as well as international regulations and best practices that govern these types of operations. Special attention is given to the risk assessment process, including the analysis of potential incidents, their consequences, and the preventive and response measures. The aim of this work is to provide a clear and comprehensive overview of the safety requirements necessary for effective planning and execution of STS operations, while minimizing potential hazards to people, the environment, and property
Components of the ECDIS system and its integration in maritime navigation
No full textECDIS (Electronic Chart Display and Information System) sustav integracija je većeg broja sustava u funkcionalnu cjelinu koja donosi korisniku mogućnost brzog pristupa svim željenim informacijama u svrhu pomorske površinske navigacije.
ECDIS sustav sastoji se od više dijelova. Ti dijelovi su zasebni sustavi koji se koriste u navigaciji, u radiokomunikaciji, te satelitski i ultrazvučni sustavi poput elektroničkih navigacijskih karata, odgovarajućeg programskog rješenja s prikazom informacija u zadovoljavajućoj rezoluciji, pozicijskih sustava, žirokompasa, senzora brzine, AIS-a (Automatski indetifikacijski sustav) i RADAR-a (Radio Detecting and Ranging).
Glavne karakteristike i funkcije su mu brza obrada podataka i njihov prikaz na zaslonu koji omogućuje upravitelju broda brzo i točno informiranje uz jednostavno korištenje.
Koristi se na svim trgovačkim i vojnim brodovima jer je tako određeno SOLAS (Safety of Life at Sea) konvencijom pa se da zaključiti da je osim u eksploatacijske svrhe, koristan u svrhu sigurnosti plovidbe i posade broda.The ECDIS (Electronic Chart Display and Information System) system is an integration of a number of systems into a functional unit that gives the user the ability to quickly access all desired information for the purpose of maritime surface navigation.
The ECDIS system consists of several parts. These parts are separate systems used in navigation, radio communication, satellite and ultrasonic systems such as electronic navigation charts, appropriate software solutions with information display in satisfactory resolution, positioning systems, gyrocompasses, speed sensors, AIS (Automated Indetification System) and RADAR.
Its main characteristics and functions are fast data processing and their display on the screen, which enables the ship captain to be informed quickly and accurately as it is simple to use.
It is used on all commercial and military vessels, as mandated by the SOLAS (Safety of Life at Sea) convention, which indicates that, in addition to its operational role, it is also important for the safety of navigation and the ship’s crew
Autonomous vehicle technology
No full textU ovom završnom radu obrađena je tematika budućnosti bez vozača. U današnjem svijetu postoje značajne tendencije da se u potpunosti prijeđe na potpuno autonomno upravljanje. Ovaj završni rad prikazuje razvoj vozila kroz povijest te ključne događaje. Rad analizira osnovna obilježja sigurnosti u prometu te njihove najbitnije čimbenike. U pogledu autonomnih vozila ovaj rad detaljno obrađuje sve vrste tehnologija (senzora) rada kod autonomnih automobila današnjice te su navedene prednosti i nedostaci autonomnih vozila kao takvih. Detaljnom analizom razina autonomije evidentna je tendencija da budućnost leži u području autonomnih tehnologija te se očekuje njihov daljnji razvoj.In this thesis, the topic of the autonomous vehicles is discussed. Nowadays, there are significant trends that are moving towards autonomous control. This thesis shows the development of the vehicle through history including the key events. The thesis analyzes the basic features of traffic safety and their most important factors. In terms of autonomous vehicles, this thesis describes in detail all types of technologies (sensors) used in today's autonomous cars and lists the advantages and disadvantages of autonomous vehicles as such. A detailed analysis of the level of autonomy shows a tendency that the future lies in the field of autonomous technologies and their further development can be expected
Maritime Liquid Cargo Market
No full textOvaj diplomski rad bavi se analizom pomorskog tržišta tekućeg tereta, s posebnim osvrtom na tankersko brodarstvo i čimbenike koji oblikuju njegovu dinamiku. U radu se razmatraju podjela i karakteristike pomorskog tržišta, uključujući cikličnost i sezonalnost, razrađuje se pojam učinkovitog tržišta. Poseban dio rada namijenjen je brodovima za prijevoz tekućih tereta poput ''prljavih'' i ''čistih'' tankera te LNG/LPG brodova. Analizira se i uloga međunarodnih organizacija poput IMO-a, BIMCO-a i INTERTANKO-a, te se prilažu privitci ugovora koji se koriste u prijevozu tekućih tereta. Završni dio rada posvećen je analizi tržišta tekućeg tereta u 2024. godini, pri čemu se koriste statički podatci i grafikoni za prikaz aktualnih trendova i kretanje vozarina. Rad pruža cjelovit uvid u strukturu i funkcioniranje tržišta tekućeg tereta, uz prikaz glavnih izazova i prednosti koje utječu na njegov razvoj.This thesis focuses on the analysis of the maritime liquid cargo market, with particular emphasis on tanker shipping and the factors that shape its dynamics. The thesis examines the structure and characteristics of the maritime market, including its cyclicality and seasonality, and elaborates on the concept of an efficient market. A dedicated section of the thesis addresses ships used for transporting liquid cargoes, such as ''dirty'' and ''clean'' tankers, as well as LNG and LPG carriers. The role of international organizations such as the IMO, BIMCO and INTERTANKO is also analysed, and attachments of contracts used in liquid cargo transport are included. The final part of the thesis is devoted to an analysis of the liquid cargo market in 2024, using statistical data and charts to illustrate current trends and freight rate developments. The thesis provides a comprehensive overview of the structure and the functioning of the liquid cargo market, highlighting the main challenges and advantages that influence its development
FLNG Facilities as a Solution for Natural Gas Liquefaction
No full textU završnom radu analizirani su dizajn, koncept i operativni segmenti plutajućih postrojenja za ukapljivanje prirodnog plina. Obrađen je povijesni razvoj FLNG tehnologije te razlozi prihvaćanja takve tehnologije u industriji. Opisane su ključne tehnološke komponentne od samog dizajna, spremnika, sustava za iskrcaj LNG-a do sustava sidrenja. Naročita pažnja je posvećena procesu ukapljivanja prirodnog plina na FLNG postrojenjima, uključujući pripremu plina za ukapljivanje i same tehnologije ukapljivanja. U radu su dodatno razmotrene prednosti FLNG postrojenja, poput efikasnosti, manjeg utjecaja na kopnenu infrastrukturu, tehnička ograničenja i utjecaja na okoliš. Peto poglavlje donosi pregled trenutnih FLNG postrojenja u svijetu i nakon toga dolazi analiza FLNG postrojenja u zaključku.The final paper analyzes the design, concept and operational segments of floating liequefied natural gas (FLNG) facilities. It covers the historical development of FLNG technology and the reasons for the adoption of FLNG in the industry. Key technological components are disracebed, from the design itself, storage tanks, LNG offloading systems, to mooring systems. Particular attention is given to the process of natural gas liquefaction on FLNG units, including gas pre-treatment and liquefaction technologies. The advantages of FLNG facilities are discussed, such as efficiency, reduced impact on onshore infrastructure, technical limitations and enviromental impact. Chapter five provides an overview of current FLNG facilities in the world, followed by an analysis of the entire content in the conclusion