Impact of shipbuilding cycle and regulations on shipowner´s operations

Brodogradnja opskrbljuje tržište novim brodovima dok rezališta otkupljuju brodove koji više nisu isplativi na tržištima. Što se tiče njihove gospodarske strukture, te dvije industrije su vrlo različite. Brodogradnja je inženjerski posao koja prodaje velike i sofisticirane proizvode koje se uglavnom grade u industrijskim zemljama: Južnoj Koreji, Japanu, Kini, Europi i SAD-u. Zahtijevaju se značajna ulaganja i visoka razina tehničke i upravljačke stručnosti za projektiranje i proizvodnju trgovačkog broda. Industrija rezališta brodova uglavnom je smještena u zemljama niskih troškova rada. U nekim državama rezanje brodova odvija se na obali. Pritom se koristi primitivan ručni alat i alat za rezanje

Database security

Baza podataka je najsloženiji oblik strukture i organizacije podataka te ju možemo definirati kao jedinicu u koju se skladište sve informacije i podatci u svrhu jednostavnog pristupanja i upravljanja istima. Zbog povećanja količine podataka s kojom raspolažu tvrtke i organizacije, raste i važnost očuvanja sigurnosti baza podataka kako bi se spriječio neovlašteni pristup od strane zlonamjernih korisnika. Ugrađivanje sigurnosnih elemenata u Sustave za upravljanje bazama podataka predstavlja važan način za povećanje njene sigurnosti. Razinu sigurnosti informacijskog sustava, tehnologije i informacija koje informacijski sustav sadrži određuje sigurnosna politika. U ovom završnom radu cilj je prikazati koje sigurnosne prijetnje postoje, te koji su mogući načini sprječavanja napada i zaštite podataka.Database is the most complex form of data structure and organization, which can be defined as a unit in which all information and data are stored for the purpose of easy access and management. Due to the increase in the amount of data that companies and organizations posses, it is important to maintain the security of databases in order to prevent unauthorized access by malicious users. Incorporating security elements into Database Management Systems is an important way to increase its security. The level of security of the information system, technology, and information that the information system contains is determined by the security policy. In this final paper, the aim is to present what security threats exist, as well as possible ways to prevent the attack on the database or how to protect data

Quantitative Analysis of Fuel Consumption and Fuel Sediments Separation as a Function of Fuel Type and Ship Operation Mode on Product/Chemical Tanker Example

Fuel consumption onboard is influenced on several factors but most crucial is ship operation mode and fuel type in use. Conventual fuel preparation process onboard consists of several stages. One of the most essential processes is centrifugal separation treatment operation onboard, which consists of introducing fuel into the field of high centrifugal field, where impurities and sediments are separated from fuels. The quantity of separated sediments and impurities from the fuel is essential for accurate calculating the remaining fuel quantity on board (ROB). The purpose of this paper is to determine and verify the influence of potential factors that can affect the quantity of fuel consumption and separated sediments quantity from the fuel based on actual data from real product/chemical tanker powered by conventional fuels. By means of statistical analysis the average values, minimums, maximums, standard deviations, and variations, median and modes, standard errors for separated sludge from fuel, heavy fuel consumption (HSHFO) and diesel fuel consumption (LSMGO) during entire observed period and during specific operations modes are obtained. Furthermore, regression formulas between separated sediments from fuel vs fuel consumption during each ship operation mode are generated. Finally, by means of single and multifactorial analysis significant influence of ship operations mode on fuel consumption and separated quantity has been confirmed. This research contributed to find relations more accurately between separated sediments quantity to fuel consumption that might be used for more accurate emission calculation

Characteristics of air freight transport in integrated and multimodal transportation

Zračni prijevoz tereta ima značajnu ulogu u globalnom transportnom sustavu. Kao dio prometnog sustava konstantno je podložan razvitku i prilagodbi suvremenim transportnim tehnologijama. Karakteristike zračnog prijevoza tereta omogućuju brz i siguran prijevoz gotovo svih vrsta tereta. Zrakoplovi za prijevoz tereta svojim tehničko-tehnološkim obilježjima omogućuju brzu i jednostavnu manipulaciju tereta te sa gotovo potpunom paletizacijom i kontejnerizacijom tereta predstavljaju odličan primjer integralnog prijevoza. Uključenost zračnog prijevoza u multimodalni transport nije u potpunosti definirana i može se proučavati sa različitih stajališta ovisno o načinu tumačenja same definicije.Air freight transport plays a significant role in the global transport system. As part of the transport system, it is constantly subject to development and adaptation to modern transport technologies. The characteristics of air freight transport enable the fast and safe transport of almost all types of cargo. Cargo aircraft, with their technical and technological features, enable quick and easy cargo handling and with almost complete palletization and containerization of cargo, represent an excellent example of integrated transport. The inclusion of air transport in multimodal transport is not fully defined and can be studied from various standpoints depending on the interpretation of the definition itself

The influence of exhaust valve burnout on main engine operation

Rad daje kratki opis ispušnog ventila dvotaktnog sporookretnog dizelskog brodskog motora, opisuje njegovu ulogu, princip rada te osnovne dijelove. Cilj ovog rada je istražiti utjecaj različitih postotaka nagorenosti ispušnog ventila na rad glavnog motora i njegovih osnovnih parametara. U radu su dane tablice s vrijednostima dobivenih uz pomoć simulacija različitih stanja nagorenosti ispušnog ventila. Na temelju dobivenih vrijednosti izrađeni su dijagrami koji prikazuju utjecaj nagorenosti ventila na rad glavnog motora.The paper gives an insight into the two-stroke slow-speed diesel marine engine exhaust valve, it's task, how it works and the basic parts. The purpose of this paper is to investigate the influence of different percentages of exhaust valve burnout on the operation of the main engine and its basic parameters. The paper presents tables with values obtained by simulation, at different conditions of the exhaust valve. Based on the obtained values, flow charts are drawn to show the impact of burnt exhaust valves on the main engine operation

European plans for the recovery of maritime after the COVID-19 pandemic

Pojavom korona virusa cijeli svijet suočio se njegovim utjecajima na razne aspekte ljudskog života. Tako je ova bolest imala utjecaja i na pomorstvo. U ovome radu opisani su utjecaji pandemije COVID-a 19 na pomorstvo koji su uglavnom negativni, no kroz rad prikazane su i neke pozitivne promjene. Negativni učinci su pogodili cijeli svijet, pa tako i Europsku uniju. Stoga je Europska unija donijela određene planove za oporavak, kojima želi pomoći svojim državama članicama da se što prije i lakše oporave od ove krize uzrokovane pandemijom. Također su prikazani i utjecaji na pomorstvo u Republici Hrvatskoj kao članici Europske unije te na koji način će raditi na oporavku. Rad sagledava sve planove oporavka te daje uvid u to kako ti planovi utječu na pomorstvo.With the appearance of the corona virus, the whole world faced its effects on various aspects of human life. This disease has also had an impact on maritime and shipping. This paper describes the impacts of the COVID-19 pandemic on shipping, which are mostly negative, but it also shows some positive changes. The negative effects hit the entire world, including the European union. Therefore, the European union has adopted certain recovery plans to help its member states recover as quickly and easily as possible from this crisis caused by the pandemic. Also there are shown the impacts on shipping in the Republic of Croatia as a member of the European union and how they will work towards recovery. The paper examines all recovery plans and provides insight into how these plans affect maritime and shipping

Permament data storage technologies

Ovaj završni rad temelji se na istraživanju trajne pohrane podataka. U radu će se obraditi princip rada trajnih memorija, način izvedbe memorija, njihova primjena i najznačajnije vrste trajnih memorija. Medija za trajnu pohranu podataka je jedan od najvažnijih elemenata u osobnom računalu. Da nema trajnih memorija ne bi bilo moguće pohraniti operativne sustave, programe, slike, video zapise itd. Razvitkom ove tehnologije kroz vrijeme kapacitet za pohranu je rastao a cijena samih uređaja je padala. Danas postoje različite tehnologije za zapis podataka neke od njih su novije a neke starije koje još uvijek nalaze svoju primjenu.This thesis is based on the research of permanent data storage. The paper will cover the working principle of non-volatile memories, the way memories are made, their application and the most important types of non-volatile memories. Media for permanent data storage is one of the most important elements in a personal computer. If there were no permanent memories, it would not be possible to store operating systems, programs, images, videos, etc. With the development of this technology over time, the storage capacity grew and the price of the devices themselves fell. Today there are various technologies for recording data, some of them are newer and some are older which still find their application

On Detection of Anomalous VHF Propagation over the Adriatic Sea Utilising a Software-Defined Automatic Identification System Receiver

This paper represents observations on detection of Very High Frequency (VHF) anomalous propagation over the area of the Adriatic Sea. During the research campaign, a Software Defined Radio (SDR) Automatic Identification System (AIS) receiver was employed for collection of AIS data packets at a fixed location in the Northern Adriatic. Data were collected during the 24-h period (25 February 2023 15:32 LT to 26 February 2023 15:32 LT), providing information from 115 AIS targets, or 159 965 AIS packets with 54.3% Packet Error Rate (PER), respectively. Subsequent analysis and post- processing of successfully demodulated signals and decoded packets was presented further. In certain instances, the SDR AIS receiver detected, received and decoded data packets from AIS targets distant several orders of magnitude larger than the VHF nominal ranges. To determine the magnitude of line-of-sight and over-the-horizon radio waves propagation, the great circle distances between the SDR AIS receiver antenna and AIS packets’ decoded positions were calculated, revealing hundreds of Nautical Miles (NM). Possible reasons for these occurrences, including tropospheric scattering, diffraction, ionospheric sporadic E layer and refraction were discussed and evaluated, in accordance, among others, with the previous research. By exclusion criteria and neglection of possible causes, it was concluded that the enhanced, over-the-horizon propagation of AIS signals occurred as a result of refraction effects, namely trapping/ducting, subrefraction and superrefraction. Data from nine World Meteorological Organization (WMO) radiosondes surrounding the greater reception area were collected for the same observation periods. Atmospheric profiles were created using Advanced Refractive Effects Prediction System (AREPS) program, and analysed for each individual station measurement. The results confirmed anomalous, over-the-horizon enhanced propagation and their probable origins, i.e., the occurrence of refractive conditions in the atmosphere over the Adriatic Sea area. These findings provide a solid foundation for further research in the area of propagation of VHF signals and their anomalous features caused by the atmospheric phenomenon effects

Container ship fleet route evaluation and similarity measure-ment between two shipping line ports

The characterization of ship routes and route similarity measurement based on Automatic Identification System (AIS) data are topics of various scientific interests. Common route research approaches use available AIS identifiers of ship types. However, assessing route and similarity profiles for individual fleets requires collecting data from secondary sources, dedicated software libraries or the creation of specific methods. Using an open-source approach, public AIS and ship data, we evaluate route characteristics for the container ships of a single fleet in a six-month period, calling on two selected ports of the shipping line on the USA East Coast. We evaluate the routes in terms of length, duration and speed, whereas for the similarity measurement we employ the discrete Fréchet distance (DFD). The voyage length, duration and average speed distributions were observed to be moderately positive (0.77), negative (−0.62), and highly positively skewed based on the adjusted Fisher– Pearson coefficient of skewness (1.23). The most similar voyages were from the same ships, with the lowest discrete Fréchet distance similarity value (0.9 NM), whereas 2 different ships had the most dissimilar voyages, with the highest DFD value (14.1 NM). The proposed methodology enables assessment of similarities between individual ships, or between fleets

Analysis of Zadar airport

Zračni promet kao jedna od grana prometa zadnjih godina bilježi veliki porast u odnosu na druge vrste prometa. U pružanju kvalitetnih, sigurnih i brzih usluga najvažniju ulogu imaju zračne luke u kojima se odvija proces prihvata i otpreme putnika, prtljage, tereta i pošte. Sve usluge koje se pružaju u zračnim lukama izuzetno su brze i bitne u vremenu, zbog toga infrastruktura i kapaciteti zračne luke imaju veliku ulogu u procesima tehnologije prihvata i otpreme. Temelj kvalitetnog procesa prihvata i otpreme putnika i prtljage obuhvaća registraciju putnika, provjeru dokumentacije, zaštitne preglede, ukrcaj putnika i prtljage, obavješćivanje posade, zatvaranje leta, aktivnosti pri dolasku ili odlasku zrakoplova. Zračna luka Zadar od svog otvaranja do danas bilježi stalan porast prometa i pruža svim putnicima vrhunsku uslugu i sigurnost. U cilju što boljeg, sigurnijeg i bržeg funkcioniranja Zračne luke Zadar javlja se i potreba za proširenjem postojećih kapaciteta kako bi se pravodobno i sigurno moglo što većem broju putnika pružiti kvalitetna i sigurna usluga. Analizom povijesnog razvoja Zračne luke Zadar od njezine izgradnje, potpune devastacije u Domovinskom ratu, obnove nakon razaranja pa do respektabilne zračne luke danas, obraditi će se svi aspekti koji pokazuju kako je potrebno planski i učinkovito donositi rješenja i ostvarivati buduće projekte za proširenje postojećih kapaciteta i na taj način osigurati kvalitetu usluga svim korisnicima zračne luke.Air traffic is one type of transportation that in the last few years marks huge growth in relation on other types of transportation. In giving the quality, safe and fast service , the most important role is on airports, in which services like reception and dispatch of passengers, luggage, cargo and mail is taking places. All services given in airport are quick and essential in time, because of that infrastructure and capacity of airports have great role in process of reception and dispatch. Foundation of quality process of reception and dispatch of passengers and luggage, includes registration of passengers, document verification, security check, embarkment of passengers, loading of luggage, informing the crew, closing the flight, and activity's on planes arrival and departure. Zadar airport from its beginnings till this day marks constant increase of traffic, and provides all its passengers excellent service and safety. In order to function better, safer and faster, Zadar airport needs to expand existing capacities, in order to be able to provide quality and safe service to as many passengers as possible in timely and safe manner. Analyzing the historical development of Zadar airport from its construction, complete devastation in Croatian war of independence, renovation after destruction, all the way to respectable airport it is today, all aspects will be processed that's show how it is necessary to plan and effectively bring solutions and implement future projects to expand existing capacities, and thus ensure the quality of services for all airports users