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Production and distribution of electrical and heat energy in the Rijeka oil Refinery
No full textU završnom radu opisana je proizvodnja i distribucija električne i toplinske energije u Rafineriji nafte Rijeka, pogonima lokacije Urinj i Mlaka. Ukratko je opisana povijest Rafinerije nafte Rijeka s osvrtom na prvu električnu centralu u Rijeci na Mlaci, koja se i danas nalazi u krugu Rafinerije, te modernizacija Rafinerije na lokaciji Urinj (Kostrena). Također, u radu su navedene i opisane industrijske energane i toplane, poglavito Energana Rafinerije nafte Rijeka. U dijelu rada opisna je distribucija električne energije (distribucijska mreža, trafostanice, transformatori i sl.) s osvrtom na distribuciju električne energije u Rafineriji nafte Rijeka.The final paper describes the production and distribution of electrical and thermal energy in the Rijeka Oil Refinery, Urinj and Mlaka locations. The history of the Rijeka Oil Refinery is briefly described with reference to the first electric power plant in Mlaka (city of Rijeka), which is still located in the vicinity of the Refinery, and the modernization of the Refinery at the Urinj (Kostrena) location. Also, the paper lists and describes industrial power plants and heating plants, especially Power plant of Rijeka Oil Refinery. The part of the paper describes the distribution of electricity (distribution network, substations, transformers, etc.) with reference to the distribution of electricity in the Rijeka Oil Refinery
Sustainable activities in Croatian marinas – towards the “green port” concept
No full textDue to the intensity of marina activities and global climate change, marinas are facing the challenge of sustainability. Therefore, the concept of “green port” has now become a requirement. In practice, the term “green port” describes the activities of all stakeholders involved in the port business towards a sustainable development of the port. This paper aims to provide an insight into the current application of sustainability principles and the concept of “green port” in Croatian marinas. Therefore, the concept of “green port” is described. Furthermore, the framework (regulations, policies, international and national certificates and programs) for sustainable activities in Croatian marinas are analyzed. The main part of the paper is the analysis of sustainable activities, i.e. practices in Croatian marinas related to eco-spatial design, standardization and awarding system, energy transition, sustainable waste, water and air systems. Therefore, positive sustainable practices in selected Croatian marinas and aspects that need improvement are identified
Model for port service quality and intermodality assessment applying fuzzy logic
No full textPort terminals, as the starting and ending points of the technological process in the transport of goods, are also logistic centers for the provision of services of loading/unloading and storage of goods. Improving the process of transporting goods and achieving competitiveness is not possible without quality port service and customer satisfaction with the service provided, and reduction of traffic congestion and environmental pollution within the guards in which the ports are positioned.
This scientific research aimed to analyze, using scientific methodology, the factors influencing the assessment of port service quality and intermodality in the Port of Rijeka and to develop a model for port service quality assessment by implementing fuzzy logic. The model was tested by simulation based on the evaluation of the criteria of influential parameters with inaccurate and indeterminate input data. The test results provide an assessment of the quality provided by port service and intermodality. The results of the research will be used to improve the transport service planning process to achieve greater competitiveness for the port
Control of electric motor drives, "frequency regulator"
No full textSuvremeno doba okarakterizirano je primjenom elektromotornih pogona, kako u industrijskim postrojenjima, tako i u domaćinstvima. Industrijski pogoni se kao velika postrojenja veliki potrošači električne energije te je, s obzirom na razna ograničenja po pitanju zagađenja okoliša i potrošnje energije (energetske efikasnosti), bilo potrebo uvesti neke novitete unutar takvih postrojenja radi smanjenja potrošnje električne energije. Smanjenje potrošnje električne energije ostvareno je uvođenjem noviteta u obliku tehnologije upravljanja elektromotornim pogonima koji se zasnivaju na promjenama brzine okretaja elektromotora. Takvi uređaji doprinose znatnom unapređenju, kako u smislu smanjenja potrošnje energije, tako i u smislu manjeg opterećenja određenih dijelova elektromotornog sustava koji uz korištenje nove tehnologije radi glatko i većinu vremena aktivno, bez gašenja. Promjene brzine okretaja ostvareno je suvremenom tehnologijom pretvarača frekvencije čija se ugradnja sve više počela ostvarivati u domaćinstvima unutar klimatizacijskih sustava. U diplomskom radu prikazani su razni sustavi elektromotornih pogona, njihova teorija rada, način rada u praksi te njihova modernizacija ugradnjom pretvarača frekvencije unutar elektromotornih sustava. Teorija pretvarača frekvencije prikazana je detaljno čija se upotreba u praksi predočuje daljnjim primjerom na kojem je u jednostavnom obliku uz proračun troška ugradnje i isplativosti prikazan utjecaj pretvarača frekvencije na energetsku efikasnost jednog kućnog sustava.The modern era is characterized by the use of electric drives, both in industrial plants and in households. Industrial plants, as large plants, are large consumers of electricity and, given the various restrictions on environmental pollution and energy consumption (energy efficiency), there was a need to introduce some novelties within such plants in order to reduce electricity consumption. The reduction in electricity consumption was achieved by the introduction of innovations in the form of electric motor drive management technology based on changes in the speed of rotation of the electric motor. Such devices contribute to significant improvement, both in terms of reducing energy consumption, and in terms of less load on certain parts of the electric motor system, which with the use of new technology works smoothly and most of the time actively, without shutting down. Changes in the speed of rotation are achieved by modern technology of frequency converters, the installation of which has increasingly started to be implemented in households within air conditioning systems. The thesis presents various systems of electric motor drives, their theory of operation, how they work in practice, and their modernization by installing frequency converters within electric motor systems. The theory of frequency converters is presented in detail, the use of which in practice is represented by a further example in which the influence of frequency converters on the energy efficiency of a home system is shown in a simple form along with the calculation of the cost of installation and profitability
SCADA system and his usage in Croatian railways
No full textSCADA je sustav nadzorne kontrole i prikupljanja podataka, a njezine su glavne funkcije: prikaz podataka u stvarnom vremenu, alarmiranje, trendovi i izvješćivanje s udaljenih uređaja. SCADA je sustav značajno olakšao upravljanje industrijskih postrojenja zbog efikasnije komunikacije i mogućnosti vizualizacije procesa te daljinskog upravljanja. Sastoji se od brojnih hardverskih i softverskih komponenti koje djeluju sinkronizirano na prikupljanju, obradi i prikazu podataka. SCADA se razvijala unutar tri generacije : prva- monolitička arhitektura gdje su sustavi bili samostalni bez povezanosti s drugim sustavima, druga- distribuirani SCADA sustavi gdje su postrojenja bila povezana LAN- mrežom i ostvarivala komunikaciju u stvarnom vremenu i treća- mrežna, koju koriste Hrvatske željeznice, a ona je nadogradnja druge s osnovnom razlikom u otvorenosti sustava.SCADA is a system of surveillance control and data collection, and its main functions are: real-time data display, alarms, trends and reporting from remote devices. SCADA system has significantly facilitated the management of industrial plants due to more efficient communication and the possibility of process visualization and remote control. It consists of a number of hardware and software components that operate in sync on data collection, processing and display. SCADA was developed within three generations: the first - monolithic architecture where the systems were independent without connection to other systems, the second - distributed SCADA systems where the plants were connected by LAN and real-time communication and the third - network, used by Croatian Railways , and it is an upgrade of the second with a fundamental difference in the openness of the system
Assessing the Possibilities of Integrating Ports into the Circular Economy
No full textPorts are very important international hubs within transport networks where various industrial and logistical activities are performed. However, by use of the closed-loop mechanism the circular economy would reduce the need for imported primary raw materials because it would treat waste as a secondary raw material. This would greatly affect the way in which ports operate because primary raw materials make up most of their cargo volume. Therefore, it is essential to evaluate the possibilities of integrating ports into the circular economy. This paper aims to use the descriptive research method to assess ports on their role in the circular economy, and based on the SWOT analysis has highlighted the key elements of circular analysis of waste streams to objectively evaluate the closed - loop mechanism. The conclusion is that due to the decline in primary raw material volumes within the circular economy, ports would therefore become centers of innovation in order to attract as many new industries as possible within their sector. The circular business model of ports would also require renewed cooperation from key actors within the port sector, the most important being the port authority, industrial clusters and academic institutions
Analysis of curriculum and ship stability teaching at maritime schools
No full textKroz ovaj diplomski rad analizira se kurikulum i koncept nastave iz područja stabilnosti broda te prijedlozi za moguća poboljšanja i izmjene. Prva dva poglavlja pobliže objašnjavaju samu nauku o stabilnosti, kodekse i zahtjeve koje studenti trebaju savladati, a koje određeni brod treba zadovoljavati uz povijesni pregled razvoja stabilnosti, teorija i poučaka. Kada se govori o nastavi i učilištima ne smije se zanemariti percepcija učenika i studenata o materiji, kao ni njihovo zadovoljstvo u vezi provođenja nastave, stoga je tome pridana pažnja u sljedećem poglavlju. Nadalje, pruža se uvid u strukovne kurikulume srednjih pomorskih škola u hrvatskoj, posebno predmete koji su u nekom pogledu vezani uz stabilnost broda. Hrvatska pomorska učilišta nalaze se u Rijeci, Zadru, Splitu i Dubrovniku, a kolegij stabilnost broda izučava na gotovo svim navedenim učilištima. U radu je također dan uvid u kurikulume nekih učilišta u inozemstvu koja imaju različit, ali zanimljiv koncept izučavanja stabilnosti broda. Na kraju samog rada, uz zaključak, dan je i osobni osvrt na moguća poboljšanja i izmjene.This thesis analyzes the curriculum and concept of teaching in the field of ship stability and suggestions for possible improvements and changes. The first two chapters explain in more detail the very science of stability, the codes and requirements that students need to master, and which a particular ship needs to meet with a historical overview of the development of stability, theories and lessons learned. When it comes to teaching and colleges, the perception of pupils and students about the subject, as well as their satisfaction with the teaching process, should not be neglected, so attention is paid to this in the next chapter. Furthermore, there is an insight into the vocational curricula of secondary maritime schools in Croatia, especially subjects that are in some respects related to the stability of the ship. Croatian Maritime Colleges are located in Rijeka, Zadar, Split and Dubrovnik, and the course studies ship stability at most of these colleges. The paper also provides an insight into the curricula of some universities abroad that have a different but interesting concept of studying ship stability. At the end of the paper, in addition to the conclusion, a personal review of possible improvements and changes is given
Market evaluation of ships in overseas trade
No full textPandemija COVID-19 utjecala je na sve gospodarske sektore na globalnoj razini. U tome nije izuzetak ni međunarodni pomorski promet. Prije pandemije COVID-19 međunarodni pomorski promet bilježio je kontinuirani rast. S pojavom pandemije, smanjena je potražnja za međunarodnim pomorskim prometom. Navedeno smanjenje identificirano je kod svih vrsta međunarodnog pomorskog prijevoza. Pandemija je smanjila i potražnju za novim brodovima kao i općenitu svjetsku flotu brodova. Takve okolnosti međunarodni pomorski promet suočile su s velikim izazovom i potrebom da se pronađu načini za realizaciju međunarodnog pomorskog prometa u uvjetima krize. Pandemija je ukazala i na ranjivost međunarodnog pomorskog prometa i na njegovu zavisnost o brojnim čimbenicima, poput, slobodi kretanja, otvorenosti nacionalnih granica i dr. Posljedično, pandemija je imala i negativne učinke na evaluaciju brodova u prekomorskoj trgovini.The COVID-19 pandemic has affected all economic sectors globally. International maritime transport is no exception. Prior to the COVID-19 pandemic, international maritime traffic grew steadily. With the onset of the pandemic, the demand for international maritime transport decreased. This reduction has been identified in all types of international maritime transport. The pandemic has also reduced demand for new ships as well as the general world fleet of ships. Such circumstances have faced international maritime transport with a great challenge and the need to find ways to realize international maritime transport in times of crisis. The pandemic also pointed to the vulnerability of international maritime traffic and its dependence on numerous factors, such as freedom of movement, openness of national borders, etc. Consequently, the pandemic had negative effects on the evaluation of ships in overseas trade
Green logistics
No full textU današnje vrijeme, u doba u kojem se iskorištavaju sva prirodna bogatstva i blaga koja nam stoje na raspolaganju, naši postupci i propusti dovode u sumnju opstanak okoline, ali i ljudi. Gomilanje i neodgovarajuće odlaganje otpada može imati vrlo velik utjecaj na buduće generacije. Kako broj stanovnika raste, tako raste i količina otpada. Potreba za ekološki prihvatljivim i održivim lancem opskrbe je neosporna. S tim na umu ne čudi što se u posljednje vrijeme sve više koristi pojam „zelene“ logistike. Logističke aktivnosti uključuju prijevoz tereta, skladištenje, upravljanje zalihama, rukovanje materijalima i svu srodnu obradu informacija. Glavni je cilj zelene logistike koordinirati ove aktivnosti na način koji zadovoljava zahtjeve kupaca uz minimalne troškove.Uzimajući primjer svijeta i pametnih zelenih gradova oko nas, trebamo se zapitati što možemo učiniti bolje i učinkovitije za poboljšanje okoliša. Koncept „zelena“ logistika kreće od nas samih. Svi koji se bave nekom vrstom logistike, trebali bi voditi računa o tome da osim zadovoljenja potreba potrošača, moraju misliti na zaštitu životne sredine. Velike kompanije moraju svojim primjerom pokazati koliko je bitno živjeti u skladu s okolinom
Reverse logistic
No full textUzimajući u obzir činjenicu da je povratna logistika relativno mlada grana gospodarstva, za koju još nisu provedena velika istraživanja u okviru njezina unaprjeđenja, ne čudi podatak da je upravo ona tek unazad nekoliko godina postigla status sve većeg broja istraživanja u aktualnim znanstvenim radovima. Sama struktura ovog rada temelji se na nekoliko poglavlja, čime su obuhvaćena područja logistike i njezina razvoja, zatim podsustavi poslovne logistike čime dolazimo do pojma povratne logistika koja je ujedno i glavni predmet istraživanja ovog diplomskog rada. U okviru povratne logistike, navode se njezina glavna obilježja, te nositelji, kao i ključna područja povratne logistike a koja se tiču povrata proizvoda kao i njihovo recikliranje. U okviru pojma reciklaže koji se danas sve više koristi navode se i neke ekonomske koristi i sama budućnost reciklaže, kao i mogući pravci razvoja zelene logistike. Kako bi se ova problematika vezala uz primjenu u praksi, navodi se što je to održivo gospodarenje otpadom na europskoj razini, ali i na razini Republike Hrvatske, čime se ističe i plan sprječavanja nastanka otpada. U okviru gospodarenja otpadom na razini područja Grada Rijeke, navodi se i primjer rada u praksi društva za gospodarenje otpadom tvrtke Metis d.d.Taking into account the fact that return logistics is a relatively young branch of the economy, for which no major research has yet been carried out as part of its improvement, it is not surprising that it has only recently achieved the status of an increasing number of researches in current scientific works. The very structure of this work is based on several chapters, which cover the areas of logistics and its development, then the subsystems of business logistics, which brings us to the concept of reverse logistics, which is also the main subject of research in this thesis. In the framework of return logistics, its main features and carriers are listed, as well as the key areas of return logistics that concern the return of products as well as their recycling. Within the concept of recycling, which is used more and more today, some economic benefits and the very future of recycling are mentioned, as well as possible directions for the development of green logistics. In order to relate this issue to its application in practice, it is stated what sustainable waste management is at the European level, but also at the level of the Republic of Croatia, which highlights the waste prevention plan. Within the scope of waste management at the level of the City of Rijeka, an example of the work in practice of the waste management company Metis d.d