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Contribution of renewable energy sources in electrical balance of the Republic of Croatia
No full textUzimajući u obzir porast cijena fosilinih goriva, kao i sve veću potrebu za
provođenjem mjera za očuvanje okoliša, u Hrvatskom kao i u globalnom gospodarstvu
dolazi do sve veće svijesti o važnosti korištenja energije iz obnovljivih izvora. Većina
zemalja, među kojima je i Hrvatska, imaju cilj povećati udio obnovljivih izvora energije u
energetskoj bilanci, glavni razlozi za to su smanjenje negativnog utjecaja na okoliš, te
smanjenje ovisnosti o fosilnim gorivima. Za ostvarenje postavljenog cilja veliki značaj ima
primjena energetskih sustava u kojim se direktno ili indirektno koristi energija Sunca.
Republika Hrvatska ima znatan potencijal za korištenje energije iz obnovljivih izvora, te bi
povećanje udjela takvih izvora, doprinjelo energetskoj neovisnosti i smanjenju emisije
štetnih tvari.
U radu je dat pregled tehnologija za dobivanje električne energije iz obnovljivih
izvora, kao i pojedinačni i ukupni doprinos obnovljivih izvora energetskoj bilanci. Na
raspoloživost i isplativost korištenja obnovljivih izvora energije znatan utjecaj imaju
geografske značajke i klimatski uvjeti. Električna energije iz obnovljivih izvora u Hrvatskoj
se uglavnom dobija iz hidroelektrana, vjetroelektrana i solarnih fotonaponskih elektrana, dok
ostali obnovljivi izvori imaju zanemarivi udio ili se uopće ne koriste. U radu se analizira
pojedinačni i ukupni doprinos energetskoj bilanci hidroelektrana, vjetroelektrana i solarnih
fotoelektričnih elektrana za razdoblje od pet godina. Prikazani su i planovi za dobivanje
električne energije iz obnovljivih izvora u Hrvatskoj, gdje će se nastojati poduzimati mjere
koje vode prema održivom razvoju. Iz provedene analize proizlaze smjernice za povećanje
kapaciteta za dobivanje električne energije iz obnovljivih izvora.Considering the rise of fossil fuel prices, as well as the increasing needs to implement
measures for environmental preservation, there is a growing awareness in the Croatian and
global economy on importance of using energy from renewable sources. Most countries,
including Croatia, have a goal to increase the share of renewable energy in their energy
balance, with the main reasons being to reduce negative impact on the environment and
reduce dependence on fossil fuels. The implementation of energy systems that directly or
indirectly use solar energy is of great importance in achieving this goal. The Republic of
Croatia has significant potential for using energy from renewable sources, and increasing the
share of such sources would contribute to energy independence and reducing harmful
emissions.
This paper provides an overview of technologies for generating electricity from
renewable sources, as well as individual and total contributions of renewable sources to the
energy balance. The availability and cost-effectiveness of renewable energy sources are
greatly influenced by geographical features and climate conditions. Electricity from
renewable sources in Croatia is mainly generated from hydroelectric power plants, wind
turbines, and solar photovoltaic power plants, while other renewable sources have a
negligible share or are not used at all. This paper analyze the individual and total
contributions of hydroelectric power plants, wind turbines, and solar photovoltaic power
plants to the energy balance over a five-year period. Plans for generating more electricity
from renewable sources in Croatia are also presented, and measures leading to sustainable
development that will be taken are also presented. The analysis might provide guidelines for
increasing the capacity for generating electricity from renewable sources
The role of intelligent transport systems in reducing pollution
No full textPredmet ovog diplomskog rada su inteligentni transportni sustavi i njihov utjecaj na onečišćenje
okoliša. Općenito, uloga inteligentnih transportnih sustava je postizanje smanjenja prometnih
nesreća, povećanje efektivnog kapaciteta cesta, ušteda vremena provedenog na putu i sl., ali
važan aspekt inteligentnih transportnih sustava je i utjecaj na zaštitu okoliša, odnosno na
onečišćenje okoliša. U radu je opisani utjecaj prometa na onečišćenje okoliša i utjecaj
inteligentnih transportnih sustava pri smanjenju onečišćenja okoliša, kao i izazovi i ograničenja
s kojima se mogu susresti pri korištenju inteligentnih transportnih sustava te se analizira
inteligentni transportni sustav kao smart mobility rješenje za smanjenje onečišćenja okoliša.
Također, provedeno je primarno istraživanje o primjeni inteligentnih transportnih sustava u
određenom području.The subject of this thesis is intelligent transport systems and their impact on environmental
pollution. In general, the role of intelligent transport systems is to reduce traffic accidents,
increase the effective capacity of roads, save time spent on the road, etc., but an important
aspect of intelligent transport systems is also the impact on environmental protection, i.e.
environmental pollution. The paper describes the impact of traffic on environmental pollution
and the impact of intelligent transport systems in reducing environmental pollution, as well as
the challenges and limitations we face when using intelligent transport systems, and analyzes
the intelligent transport system as a smart mobility solution to reduce environmental pollution.
Also, primary research was conducted on the application of intelligent transport systems in a
certain area
Multi-Criteria Analysis of Coast Guard Resource Deployment for Improvement of Maritime Safety and Environmental Protection: Case Study of Eastern Adriatic Sea
No full textEuropean maritime states are facing increasing challenges that threaten national security, maritime traffic safety, and environmental protection: increasing maritime traffic, increase in nautical tourism, oil spills, migrant boats, drug smuggling, etc. The Coast Guard is one of the most important government agencies to respond to these challenges. However, the speed of response to incidents depends on the geographical and geostrategic deployment of Coast Guard resources, especially of its homeports. The main objective is to have the Coast Guard’s homeports as close as possible to the national border at sea so that the response time to an incident is as fast as possible. However, there are many other criteria that affect the selection of the maritime location of the Coast Guard homeport. These other criteria (security issues, logistic issues, hydrographic and oceanographic features, and similar) are often in conflict with geographical locations on small remote islands that are close to the state border at sea. Therefore, this research analyzed and proposed the criteria set used to assess the maritime locations that could be potential Coast Guard homeports. A large sample of experts has been interviewed to evaluate the proposed criteria set and to propose criteria weights, thus creating the multi-criteria analysis model for the improvement of the spatial distribution of Coast Guard resources. The proposed model is based on the PROMETHEE method and provides evaluation and ranking of the maritime locations in order to help the Government prioritize the development of the maritime locations into the homeports for the deployment of Coast Guard resources. The case study of the eastern Adriatic Sea with real-world maritime locations and data was used to test the proposed model. The results have shown that, with proper strategic planning of the deployment of Coast Guard resources, the sustainability, safety, and security of the sea and the coast can be increased
The impact of transporation on society and the environment
No full textPromet je neizostavan element modernog društva, omogućujući povezivanje ljudi, kultura, gradova, država i kontinenata. Njegova uloga u ekonomskom razvoju, dostupnosti javnih usluga i poboljšanju kvalitete života je neprocjenjiva. Podjela prometa na prometne grane pokazuje kompleksnost i raznolikost transportnih sustava koji zadovoljavaju različite potrebe za kretanjem ljudi i roba. Onečišćenja izazvana nesrećama i havarijama, posebno u pomorskom prometu, predstavljaju ozbiljan rizik za okoliš. Izlijevanje nafte i kemikalija može imati dugoročne posljedice na morske ekosustave, dok gubitak tereta u more dodatno ugrožava morski okoliš. Prema tome, ključne mjere uključuju stroge regulative, primjenu naprednih sigurnosnih tehnologija i efikasne planove za hitne intervencije. Zaključno, prometni sustavi moraju se razvijati u smjeru održivosti kako bi se smanjili negativni utjecaji na okoliš i zdravlje ljudi. To uključuje prijelaz na čišća goriva, unapređenje energetske efikasnosti transportnih sredstava i povećanje udjela javnog prijevoza i aktivne mobilnosti.This final paper aims to highlight the importance and usefulness of transportation, but also its harmful effects on the environment and human health. Transportation is an essential element of modem society, enabling the connection of people, cultures, cities, countries, and continents. Its role in economic development, access to public services, and the improvement of quality of life is invaluable
Attitudes towards Electronic Voting and Commenting in Business, Private and Public Meetings
No full textThis paper analyses attitudes toward meeting app features that support collaboration in business, private, and public affairs and offers an entity relationship diagram of an electronic meeting system (EMS) that can be successfully applied in those three spheres. An empirical research was conducted on a sample of 120 (N) respondents from the Republic of Croatia, while the research instrument was an online questionnaire containing 15 mandatory and 2 open-ended questions. The analysis revealed a statistically significant positive and strong relationship between organisations that should use an EMS but do not use it and organisations that spend too much time and resources on managing official meetings (τb = .576, p < .01). 48.3% of respondents claim that their organisations should use an EMS in business operations, while 57.5% of respondents believe that the EMS improves productivity. 65% of respondents agree and strongly agree that it is desirable to use authorised electronic voting in public affairs, while 33.4% of respondents agree and strongly agree that they would like to use the electronic voting system in private affairs. The conducted research shows that followers are more inclined to vote anonymously (U = 1109, z = -2.947, p = .003, r = .07) and comment anonymously (U = 1178, z = -2.580, p = .010). , r = .06) from their leaders. For this reason, authors have designed an entity relationship diagram of an EMS that supports both anonymous and transparent interaction
Intelligent traffic management systems
No full textInteligentni sustavi upravljanja prometom (ITS) predstavljaju ključnu komponentu modernizacije prometne infrastrukture i povećanja učinkovitosti transportnih mreža. U Republici Hrvatskoj, ITS sustavi su rano prepoznati i uvedeni u cestovni i željeznički promet. Intenzivna implementacija ITS sustava započela je s razvojem autocesta početkom 21. stoljeća, no nedostatak sustavnog pristupa na nacionalnoj razini još uvijek rezultira umanjenom interoperabilnošću, povećanim troškovima održavanja i lošom koordinacijom.
Ulazak Hrvatske u Europsku uniju omogućio je unapređenje zakonodavnog okvira i donošenje planskih smjernica za ITS projekte. Unatoč zadovoljavajućim istraživačko-razvojnim kapacitetima, najveći izazov ostaje nedovoljna povezanost s gospodarstvom. Osnivanje Koordinacijskog tijela za razvoj inteligentnih transportnih sustava u Hrvatskoj 2021. godine označava korak naprijed u postizanju sustavnog pristupa, poboljšanju interoperabilnosti i integracije s europskim standardima, te jačanju veze između obrazovanja i industrije.Intelligent traffic management systems (ITS) represent a key component of the modernization of transport infrastructure and the increase of the efficiency of transport networks. In the Republic of Croatia, ITS systems were early recognized and introduced primarily in scientific and secondary education. Intensive implementation of ITS applications began with the development of highways at the beginning of the new millennium, but the lack of a systematic approach at the national level resulted in reduced interoperability, increased maintenance costs and poor coordination.
Croatia's entry into the European Union enabled the improvement of the legislative framework and the adoption of planning guidelines for ITS projects. Despite satisfactory research and development capacities, the biggest challenge remains the insufficient connection with the economy. The establishment of the Coordination Body for the Development of Intelligent Transport Systems in Croatia in 2021 marks a step forward in achieving a systematic approach, improving interoperability and integration with European standards, and strengthening the connection between education and industry
Quantification of Expert Knowledge in Describing COLREGs Linguistic Variables
No full textThe International Regulations for Preventing Collisions at Sea 1972 (COLREGs) have been the cornerstone of maritime navigation since their introduction. Knowledge and implementation of these rules are paramount in collision avoidance at sea. However, terms found in these rules are sometimes imprecise or fuzzy, as they are written by humans for humans, giving them some freedom in interpretation. The term Very Large Ship used in Rule 7 of the COLREGs is, by its nature, fuzzy. While human navigators understand this term’s meaning, it could be challenging for machines or autonomous ships to understand such an unprecise expression. Fuzzy sets could easily describe unprecise terms used in maritime navigation. A fuzzy set consists of elements with degrees of membership in a set, making them perfect for interpreting some terms where boundaries are unclear. This research was conducted among 220 navigational experts to describe linguistic variables used in maritime regulations. This research consists of an internationally distributed questionnaire. Membership data were collected with the adapted horizontal method, and the results were statistically analyzed, followed by regression analyses to describe the range and shape of membership functions. A conceptual model of the implementation of linguistic variables is presented. The novelty of this study derives from the data collecting, modeling, and quantification of the important but neglected linguistic term Very Large Ship based on a large number of navigational experts. The same quantification method could be easily used for other COLREGs linguistic variables, which could easily lift barriers to advances in intelligent solutions based on fuzzy sets. The obtained quantified fuzzy sets can be used in decision support or control systems used by conventional or autonomous ships in the future
The Influence of Reduction in Sailing Speed on the Efficiency and Energy Potential of the Waste Heat of the Marine Diesel Engine
No full textOne of the essential conditions for the sustainable development of maritime transport is the increase
of energy efficiency, which contributes not only to economic efficiency but also to the reduction of
pollutant emissions. Reduction of pollutant emissions can be achieved by adjusting the combustion
process in the engine cylinder, after-treatment of exhaust gases, use of alternative fuels or reduction
of sailing speed. Reduction of sailing speed is widely used in container ships, as it does not require
additional investment and, if applied reasonably, has a positive effect on reducing fuel consumption
and pollutant emissions. However, it leads to an increase in sailing time, and a greater reduction in
sailing speed leads to a reduction in main engine efficiency and a reduction in the energy potential of the
waste heat. In this paper, the effects of reducing the sailing speed on the efficiency and energy potential
of the waste heat of a low-speed marine engine are investigated. The waste heat from the exhaust
gases and the engine cooling system is used to generate steam and electricity and for desalination. In
the examples studied, a 30.4% reduction in sailing speed from the planned speed results in a 53.1%
reduction in fuel consumption and a 43.8% increase in sailing time. When determining the optimal
sailing speed, it is also important to consider the specific fuel consumption data, which shows that
an engine load of 60% to 80% is optimal for efficiency. Data from the manufacturer WinGD on fuel
consumption and available waste heat for various engine loads as a function of the container ship’s
sailing speed were used for the study
The impact of the COVID-19 pandemic on maritime passenger traffic in the European Union
No full textPomorskoputnički promet je grana pomorstva koja je vrlo uspješna, posebice kada je riječ o kružnim putovanjima. Međutim, pojava COVID-19 pandemije uzrokovala je brojne negativne utjecaje na cjelokupnu pomorsku industriju. Predviđanja su ukazivala da je pomorska industrija trebala biti u znatnom porastu 2020. godine, no neočekivanom pojavom pandemije ona se nisu ostvarila. Prema provedenim istraživanjima i dostupnim podatcima, industrija se nakon popuštanja epidemioloških mjera postepeno oporavlja, ali da bi promet prometovao intenzitetom kao nekada, luke i svi ostali sudionici bi trebali težiti za unaprijeđenjem cijelog pomorskog sustava. U ovom radu usporedit će se kretanje pomorskoputničkog prometa u odabranim zemljama Europske unije u razdoblju prije pandemije, tijekom pandemije i poslije pandemije. Posebno će se istaknuti promjene koje su vidljive u ponašanju putnika na kružnim putovanjima i u primjeni novih pomorskih tehnologija.Maritime passenger traffic is a branch of shipping that is very good, especially when it comes to successful cruises. However, the emergence of the COVID-19 pandemic caused numerous negative impacts on the entire maritime industry. Predictions indicated that the maritime industry would grow significantly in 2020, but not a single unexpected pandemic has materialized. According to the conducted research and the available data, the industry is gradually recovering after the release of epidemiological measures, but in order for traffic to flow as intensively as before, ports and all other participants should strive to improve the entire maritime system. This paper will compare the movement of maritime passenger traffic in selected countries of the European Union in the period before the pandemic, during the pandemic and after the pandemic. The changes that are visible in the behavior of passengers on cruises through maritime technologies will be highlighted in particular
Operational parameters of the transportation process in one direction
No full textSvrha i cilj svakog transportnog poduzeća je da pruži što bolju uslugu prijevoza uz što manje troškove. Jedan od načina postizanja tog cilja je ostvarenje što veće iskoristivosti kapaciteta prijevoznog sredstva. Međutim, to nije uvijek moguće te prijevozna sredstva voze prazna i to uglavnom u povratnoj vožnji od mjesta istovara do početnog ishodišta. U tim povratnim vožnjama prelaze se prazni kilometri odnosno kilometri bez prihoda. U radu se istražuju razlozi i moguća rješenja za problem praznih vožnji kroz pregled jednog znanstvenog istraživanja. Nadalje, za više različitih odabranih ruta prijevoza kamene vune izračunati su eksploatacijski parametri prijevoznog procesa na temelju kojih se izvode zaključci o realiziranim rutama. Rezultati izračuna mogu biti dobre polazne smjernice za daljnja poboljšanja u smislu povećanja iskristivosti nosivosti i smanjenja koeficijenta prazne vožnje.Companies strive to provide the best possible transport service at the lowest possible cost. One of the ways to achieve this goal is to achieve the greatest possible utilization of the capacity of the means of transport. However, this is not always possible and means of transport drive empty, mostly on the return trip from the place of unloading to the starting point. In these return trips, empty kilometers are traveled, i.e. kilometers without income. The paper explores the reasons and possible solutions for the problem of empty rides through a review of a scientific paper. Furthermore, the exploitation parameters of the transport process were calculated for several different selected rock wool transport routes, on the basis of which conclusions are drawn about the realized routes. The results of the calculations can be good initial guidelines for further improvements in terms of increasing the load capacity and reducing the idle coefficient