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Sparse Time-Frequency Distribution Reconstruction Using the Adaptive Compressed Sensed Area Optimized with the Multi-Objective Approach
No full textCompressive sensing (CS) of the signal ambiguity function (AF) and enforcing the sparsity constraint on the resulting signal time-frequency distribution (TFD) has been shown to be an efficient method for time-frequency signal processing. This paper proposes a method for adaptive CS-AF area selection, which extracts the magnitude-significant AF samples through a clustering approach using the density-based spatial clustering algorithm. Moreover, an appropriate criterion for the performance of the method is formalized, i.e., component concentration and preservation, as well as interference suppression, are measured utilizing the information obtained from the short-term and the narrow-band Rényi entropies, while component connectivity is evaluated using the number of regions with continuously-connected samples. The CS-AF area selection and reconstruction algorithm parameters are optimized using an automatic multi-objective meta-heuristic optimization method, minimizing the here-proposed combination of measures as objective functions. Consistent improvement in CS-AF area selection and TFD reconstruction performance has been achieved without requiring a priori knowledge of the input signal for multiple reconstruction algorithms. This was demonstrated for both noisy synthetic and real-life signals
Environmental Requirements for Passenger Terminal Development (Case Study of Zadar County)
No full textCruising as part of nautical tourism is an important segment of maritime passenger transportation. Nautical tourism and cruise tourism have developed over the years and are experiencing increasing demand, with the exception of the pandemic period, when cruise tourism did not experience positive trends. In normal tourism conditions, high growth requires an increase in supply, which can have negative consequences for the environment. This is especially true when the destination where cruise tourism is developing has a fragile ecosystem. At a time when environmental sustainability and responsibility are becoming increasingly important, tourism supply is implementing the parameters of sustainability in its development, and cruise tourism is no exception. However, the fact is that the development of passenger terminals inevitably changes the view of the coast. The aim of this paper is to thoroughly define the parameters whose reconstruction is necessary for the construction of a passenger terminal and for which it is necessary to analyze the impact on the environment in order to make the construction itself environmentally friendly. Systematic analysis is the most appropriate method for delineating the parameters whose reconstruction could harm the environment and have negative effects on the sustainability of the ecosystem as well as on tourism and locals in the area. The results of the analysis conducted on the example of capacity construction in the coastal region of Zadar County show that special consideration must be given to protected natural values, landscape properties, population, purpose and use of space, noise and air. It can be concluded that disregarding all the construction parameters described in the study and emphasizing the financial benefits could affect the ecosystem in the long run. Besides the analyses, the proposal for the environmental monitoring program was elaborated on in this paper
Loading, transport and delivery of cargo to the consignee
No full textU radu se analiziraju i tumače svi potrebni koraci i dokumentacija u pomorskom ugovaranju. Pomorska trgovina je vrlo složen transportni proces u kojem se razna roba i teret brodovima prevoze diljem svijeta. Ukoliko takav sustav ne bi bio pravno i administrativno organiziran moguće je da se s obzirom na neizostavnost pomorskog transporta iz svjetskog gospodarstva isti vrlo otežano odvijao. Kao i u ostalim gospodarskim granama tako i u transportu bitno je pravno regulirati samo poslovanje. U radu će biti riječ prije svega o brodarskim ugovorima, ali i od drugim sličnim dokumentima. Isto tako vrlo je važno objasniti i tko su sudionici u prijevozu stvari morem te koje su njihove obaveze i prava. U radu se kroz pravno-administrativne aspekte analizira ukrcaj, prijevoz i predaja tereta primatelju.This paper analyzes and interprets all the necessary steps and documents in maritime contracting. Maritime trade is a very complex transport process in which various goods and cargo are transported around the world by ship. If such a system were not legally and administratively organized, it is possible that, given the indispensability of maritime transport in the world economy, it would be very difficult to proceed. As in other economic branches, in transport it is important to legally regulate the business itself. The paper will deal primarily with shipping contracts, but also with other similar documents. It is also very important to explain who are the participants in the transport of goods by sea and what are their obligations and rights. The paper analyzes the loading, transportation and delivery of cargo to the recipient through legal and administrative aspects
The influence of the VIT system and fuel oil temperature on main engine parameters
No full textGlavni predmet istraživanja u ovom radu je utjecaj „VIT“ sustava (eng. „Variable
Injection Timing” – hrv. Sustav za promjenjivo vrijeme ubrizgavanja) i promjene
temperature goriva na parametre rada glavnog motora. Istraživanje je provedeno na
Kongsberg-ovom simulatoru (MC90-V), na način da su objašnjene kemijske i fizikalne
karakteristike teškog goriva, koje ujedno služi i kao glavni radni medij, kao i princip
rada samog sustava goriva. Zatim su provedena ispitivanja na raznim opterećenjima
kroz raspon temperatura goriva s uključenim i isključenim VIT-om.Main subject of research in this final thesis is influence of the VIT system and change
of the fuel temperature on operating parameters of the main engine. Research was
carried out on Kongsberg's simulator (MC90-V), in such a way that the chemical and
physical characteristics of heavy fuel oil are explained, which is used for operation of
the main engine, as well as the working principle of the fuel oil system. Tests were then
performed at various engine loads across different fuel temperatures with VIT system
turned on and off
Cruise ship companies
No full textU radu je obrađen povijesni razvoj kompanija za kružna putovanja, opis i stanje trenutno vodećih kompanija te predviđanja za daljnji razvoj kompanija. Cilj rada je objasniti svrhu određene kompanije, ponudu koju nudi te usporedba trenutno najrazvijenijih kompanija za kružna putovanja glede prihoda i broja putnika prethodnih godina. Konkretno, u radu je obrađeno top 25 vodećih kompanija, te usporedba i prostorni razmještaj istih. Objašnjeni su segmenti tržišta te politika vođenja svake od kompanije. Moje mišljenje je da je rad vrlo koristan osobama koje su izrazile želju otići na kružno putovanje, a nisu sigurne koja bi kompanija najviše odgovarala njihovim zahtjevima. Stoga u radu mogu sažeto dobiti dojam o svim vodećim kompanijama na jednom mjestu i tako uštedjeti vrijeme na vlastita istraživanja i analize.The paper discusses the historical development of cruise companies, their descriptions, and the current status of the leading companies, as well as predictions for their further development. The aim of the papir is to explain the purpose of each company, the services they offer, and to compare currently most developed cruise companies in terms of revenue and the number of passengers in previous years. Specifically, the paper covers the top 25 leading companies and compares and analyses their spatial distribution. It also explains market segments and the management policies of each company. In my opinion, the paper is very useful for individuals who have expressed a desire to go on a cruise but are unsure which company would best suit their needs. By reading the paper they can quickly get an overview of all the leading companies in one place and save time on their own research and analysis
Automatic marine engine control − UNIC
No full textCilj ovog završnog rada je detaljnije istražiti UNIC sustav za automatsko upravljanje brodskim motorom i analizirati njegove ključne značajke, prednosti i primjenu u pomorskoj industriji. Ovaj rad će pružiti uvid u funkcioniranje UNIC sustava, njegove komponente i način rada te će istražiti kako se on integrira u šire kontekst automatiziranog upravljanja brodovima. U nastavku rada, analizirat će se različite vrste senzora koje se koriste u UNIC sustavu za nadzor i prikupljanje podataka o radu motora, kao i aktuatori koji omogućuju upravljanje različitim aspektima rada motora.The aim of this undergraduate final thesis is to investigate in more detail the UNIC system for automatic marine engine control and analyze its key features, advantages and application in maritime industry. This final thesis will provide an insight into the functioning of the UNIC system, its components and mode of operation and will explore how it integrates into the wider context of automated ship management. Moreover, in this final thesis the different types of sensors used in the UNIC system for monitoring and collecting data on the operation of the engine will be analyzed, as well as the actuators that enable the control of different aspects of the engine operation
Modern city delivery solutions and urban consolidation centers
No full textTemelj ovoga rada s jedne strane predstavlja funkcioniranje sustava gradskih dostava i načina na koji se ta djelatnost odvija, dok će se s druge strane temeljito izložiti i ostale operacije povezane s tom djelatnošću kojima se može učinkovito unaprijediti funkcioniranje iste. Osim općenitih činjenica o djelovanju ove grane gospodarstva, također će se što detaljnije prikazati elementi navedenog sustava na primjerima urbanih konsolidacijskih centara diljem Europe, ali isto tako će se predstaviti čimbenici funkcioniranja last – mile dostave te će se uz to povući određene paralele s implementacijom električnih dostavnih vozila u taj sustav. Na taj će se način ustanoviti zašto je korisno ulagati u moderna rješenja za obavljanje djelatnosti gradske dostave, čime se efektivno postiže održivost i smanjuje se negativan utjecaj na okoliš i stanovništvo.The basis of this paper, on the one hand, is the functioning of the city delivery system and the way in which this activity is carried out, while on the other hand, other operations related to this activity, which can improve its functioning, will be presented. In addition to general facts about the operation of this branch of economy, the elements of the mentioned system will also be presented in more detail using the examples of urban consolidation centers throughout Europe, but also the factors of the functioning of last-mile delivery will be presented, and certain parallels will be drawn with the implementation of electric delivery vehicles into that system. In this way, it will be established why it is useful to invest in modern solutions for performing urban delivery activities, which effectively achieves sustainability and reduces the negative impact on the environment and the population
Development of the maritime market in the recent period with a special reference on the transport of liquefied gases
No full textSvjetsko je tržište i roba i usluga pogođeno značajnim brojem trendova. Jedan od najboljih primjera je razdoblje u posljednjih 5 godina u kojemu su značajne stope rasta naglo obustavljene svjetskom pandemijom, da bi u konačnici iste ponovno nastavile svoj razvoj u periodu postpandemijskog oporavka. Zahvaljujući povezanosti svih tržišta, i razvoj pomorskog tržišta obilježen je globalnim kretanjima i to u kontekstu promjena u razinama vozarina i transportnih troškova, nestabilnosti i kretanja u ponudi i potražnji na ključnim pomorskim tržištima, promjenama u učinkovitosti i performansama svjetske flote, zahtjevima za izmjenom međunarodnih propisa i nacionalnih zakonskih regulativa kao i ugovora o pomorskom prijevozu robe. S druge strane tržište ukapljenog plina jednako je pogođeno svim navedenim kretanjima, no postpandemijski oporavak rezultirao je povećanjem potreba za obogaćivanjem svjetske flote povećanjem broja plovila te ispunjavanjem različitih propisa koji proizlaze iz područja zaštite okoliša i smanjenja emisije stakleničkih plinova.The world market of both goods and services is affected by a significant number of trends. One of the best examples is the period in the last 5 years in which significant growth rates were abruptly stopped by the global pandemic, only to eventually resume their development in the post-pandemic recovery period. Thanks to the connection of all markets, the development of the maritime market is also marked by global trends in the context of changes in the levels of freight rates and transport costs, instability and movements in supply and demand in key maritime markets, changes in the efficiency and performance of the world fleet, requests for changes in international regulations and national legal regulations as well as contracts on maritime transport of goods. On the other hand, the liquefied gas market was equally affected by all of the aforementioned trends, but the post-pandemic recovery resulted in an increase in the need to enrich the world fleet by increasing the number of vessels and fulfilling various regulations arising from the area of environmental protection and reduction of greenhouse gas emissions
Technology of autonomous vehicles and their use in ports
No full textLuke su lokacije na obali gdje brod može pristati i iskrcati ili ukrcati svoj teret, a služe kao ključni čvorovi u globalnoj trgovačkoj mreži te njihov strateški položaj duž obale olakšava kretanje robe povezujući proizvođače i potrošače s različitih kontinenata. Autonomna vozila su nova primjena automobilske tehnologije te uključuju svako vozilo koje ima mogućnost navigirati prometnicama i interpretirati prometne znakove bez aktivnog sudjelovanja vozača. Tehnologije koje koriste autonomna vozila su senzori, kamere, LIDAR, radar, GNSS i druge. Kako bi se osigurao manji broj pogrešaka, oštećenja i kašnjenja isporuke, ali i nesreća i ozljeda radnika, koriste se autonomna vozila i strojevi cestovnog i željezničkog prometa te bespilotne letjelice.Ports are locations on the coast where a ship can dock and load or unload its cargo. They serve as key nodes in the global trade network and their strategic location along the coast facilitates the movement of goods, connecting producers and consumers from different continents. Autonomous vehicles are a new application of automotive technology and include any vehicle that has ability to navigate roads and interpret road signs without active participation of the driver. The technologies used by autonomous vehicles are sensors, cameras, LIDAR, radar, GNSS and others. To ensure a smaller number of errors, damages and delivery delays, as well as accidents and injuries of workers, autonomous vehicles and machines for road and rail transport and unmanned aerial vehicles are being used
Hydraulic fluids and fluid flow elements
No full textOvaj završni rad opisuje svojstva i vrste fluida, te elemenata za protok fluida u
hidraulici. U prvom dijelu je objašnjeno samo nastajanje tlaka, Pascalov zakon, hidraulički
prijenosi snage i određivanje promjera cijevi. Nadalje rad obrađuje svrhe fluida, gdje su
objašnjene najvažnije djelotvornosti fluida, te karakteristike fluida, prednosti fluida, aditivi
koji pospješuju rad fluida i vrste fluida u hidraulici. U poglavlju elementi za protok fluida su
opisane cijevi, brtve, crijeva i spojnice. Navedeno je i sprječavanje propuštanja u kojem su
opisane vrste ugradbe ventila.This final work decribes properties of fluids, their types and fluid flow elements in
hydraulics. In the first chapter it is explained how is pressure being created, Pascal-s law,
hydraulic power transmissions and determination of pipe diameter. Furthermore the work
covers purposes of fluids, where the most important fluid performances are explained, as
well as characteristics of fluids, advatages of fluids, aditives which enhances the fluid
performance and types of fluids in hydraulics. In the chapter fluid flow elements are decribed
pipes, seals, hoses and connectors. Leak prevention is mentioned in which valve assemblies
are described