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Sun tracking solar panel
No full textU ovom završnom radu razrađena je tema solarne ploče za praćenje Sunca. Početak rada
ukazuje na važnost Sunčeve energije i korištenja solarnih ploča. Radi lakšeg razumijevanja
objašnjen je princip rada solarnih ploča, njihovi tipovi te princip rada komponenti koje su
potrebne za izradu sklopa. Svrha rada je povećanje iskoristivosti solarnih ploča ukoliko one
prate Sunce u odnosu na slučaj kada su fiksirane. Sklop je izrađen tako da se sa odabranim
komponentama i odgovarajućim Arduino kodom solarna ploča okreće prema istočnoj ili
zapadnoj strani što ovisi o položaju Sunca. Tako se dodatno povećava izvor Sunčeve energije
koja je obnovljiva i neiscrpna.In this final work, the topic of solar panels for sun tracking is explored. The beginning of
the paper highlights the importance of solar energy and the use of solar panels. To facilitate
understanding, the working principle of solar panels, their types, and the working principles of
the components necessary for assembling the system are explained. The purpose of the study is
to increase the efficiency of solar panels when they track the Sun compared to when they are
fixed. The system is designed so that, with the selected components and the appropriate Arduino
code, the solar panel rotates towards the east or west, depending on the position of the Sun. This
further increases the utilization of solar energy, which is renewable and inexhaustible
Emission of harmful gases with the example of public city transport in Pula
No full textStaklenički plinovi te njihov utjecaj na klimu i globalno zatopljenje uz mikroplastiku predstavljaju najveće ekološke probleme današnjice. Gospodarski rast i porast stanovništva imaju za posljedicu prekomjerno korištenje resursa, stvaranje otpada i emisiju stakleničkih plinova. Povećana razina ugljikovog dioksida u atmosferi uzrokuje porast temperature uz velike klimatske promjene. Stalnim krčenjem šuma radi izgradnje stambenih objekata, prometnica i industrijskih postrojenja znatno se umanjuje sposobnost prirode da kroz fotosintezu regulira razinu ugljika u atmosferi. Nužno je poduzeti mjere kako bi se smanjila razina stakleničkih plinova, očuvala bioraznolikost i osigurala klimatska stabilnost na dulji vremenski period. Jedna od mjera je i uporaba goriva za vozila u cestovnom prometu s nižim stupnjem emisije stakleničkih plinova. U radu je prikazan iluistrativni primjer odabira optimalnog broja vozila u gradskom prijevozu primjenom metode linearnog programiranja.Greenhouse gases and their impact on the climate and global warming, along with microplastics, represent the biggest environmental problems of today. Economic growth and population growth result in overuse of resources, generation of waste and emission of greenhouse gases. The increased level of carbon dioxide in the atmosphere causes an increase in temperature with major climate changes. The constant clearing of forests for the construction of residential buildings, roads and industrial plants significantly reduces nature's ability to regulate the level of carbon in the atmosphere through photosynthesis. It is necessary to take measures to reduce the level of greenhouse gases, preserve biodiversity and ensure climate stability for a longer period of time. One of the measures is the use of fuel for vehicles in road traffic with a lower level of greenhouse gas emissions. The paper presents an illustrative example of selecting the optimal number of vehicles in city transport using the linear programming method
Napredni model širenja požara u brodskoj strojarnici primjenom virtualne stvarnosti
No full textThe occurrence of fire on a ship poses a significant safety risk as the limited space and evacuation options can quickly increase the risk. The implementation of sound fire prevention and management strategies is critical in marine settings to protect human life, the cargo, and the vessel itself from the destructive effects of fire. To reduce the risk of fatal situations, ship owners and operators are focusing, among other things, on consistently improving the firefighting and evacuation skills of their crew members. Virtual reality (VR) fire training provides a risk-free and controlled environment in which ship personnel can practise handling real-life fire emergencies without the hazards that occur in real fire situations. This approach to training improves overall safety by providing hands-on experience and immediate feedback, which is essential for equipping crews with the skills required to deal effectively with on-board emergencies. The main limitation of conventional VR training scenarios is that they cannot accurately simulate the dynamics of fire spread. Generally, generic fire and smoke simulations based on computer games are used for these VR scenarios, which do not do justice to the true nature of real fires. However, this shortcoming can be effectively addressed by integrating computational fluid dynamics-based (CFD) models of fire spread into VR training simulations, significantly increasing the realism and educational value of these scenarios. Based on the probability of occurrence, the CFD software defines and models the three most likely fire scenarios (fire of the main engine fuel line, fire of the fuel oil purifier, and fire of oily rags left in a bucket) in the ship engine room. A software interface was developed to link CFD results and VR environment to create an advanced fire spread model in the ship engine room. In addition, a survey was conducted to determine the difference between a CFD-modelled fire in VR and a generic computer game fire in VR. According to the survey results, a group of test subjects who already have experience with fires in enclosed spaces found that the CFD-modelled fire looks more realistic than the generic fire in VR.Pojava požara na brodu predstavlja značajan sigurnosni rizik zbog ograničenog prostora i limitiranih mogućnosti evakuacije. Primjena strogih strategija prevencije i upravljanja požarima ključna je u pomorskom okruženju kako bi se zaštitili životi, teret i sam brod od destruktivnog utjecaja požara. Da bi se smanjio rizik od smrtonosnih situacija, vlasnici i posade brodova se, među ostalima, fokusiraju i na kontinuirano poboljšanje vještina gašenja požara i evakuacije svojih članova posade. Protupožarni trening unutar virtualne stvarnosti (engl. virtual reality, VR) pruža sigurno i regulirano okruženje, omogućujući posadi uvježbavanje upravljanjem stvarnim hitnim situacijama s požarom, bez opasnosti koje dolaze u stvarnim požarnim situacijama. Ovaj pristup poboljšava sigurnost nudeći praktično iskustvo i trenutnu povratnu informaciju, što je bitno za usvajanje vještina potrebnih za učinkovito suočavanje s hitnim situacijama na brodu. Glavno ograničenje konvencionalnih scenarija VR treninga leži u nemogućnosti točnog simuliranja dinamike širenja požara unutar VR okruženja. Takvi VR scenariji koriste generičke simulacije požara i dima, temeljene na principima računalnih igara, koji ne uspijevaju adekvatno replicirati pravu prirodu požara. Međutim, ovaj se nedostatak može učinkovito riješiti integracijom modela širenja požara temeljenog na računalnoj dinamici fluida (engl. computational fluid dynamics, CFD) u VR okruženje, čime se značajno pojačava realističnost i edukativna vrijednost ovih scenarija protupožarnog treninga. Koristeći takav pristup, u ovom su radu modelirana tri scenarija požara u strojarnici broda, temeljena na iskustvenoj vjerojatnosti njihova nastanka (požar na glavnoj liniji goriva motora, požar na pročišćivaču goriva i požar na zauljenim krpama u kanti). Rezultati širenja požara dobiveni računalnom dinamikom fluida preneseni su u VR okruženje posebno razvijenim programskim sučeljem, što predstavlja jedan od doprinosa ovoga rada. Time je stvoren napredni model širenja požara u brodskoj strojarnici u VR okruženju temeljen na računalnoj dinamici fluida. Nadalje, provedena je anketa među korisnicima kako bi se utvrdila uspješnost odabranog pristupa modeliranja požara nasuprot onom generičkom koji se temelji na principima računalnih igara. Prema rezultatima ankete, grupa ispitanika koji su imali prethodno iskustvo požara u zatvorenim prostorima primijetila je da požar u VR okruženju modeliran pomoću računalne dinamike fluida daje realističniji dojam od onoga generički modeliranog
Information technologies in the function of optimizing loading and transport of cargo
No full textU suvremenom poslovanju, informacijske tehnologije (IT) igraju ključnu ulogu u optimizaciji raznih segmenata, posebno u sektorima ukrcaja i prijevoza tereta. Ovaj rad istražuje kako IT tehnologije transformiraju i unapređuju procese u vezi s ukrcajem i prijevozom, te kako dovode do veće efikasnosti u odnosu na tradicionalne metode koje nisu koristile IT. Jedan od ključnih aspekata ovog rada jest analiza upotrebe proširene stvarnosti (AR), virtualne stvarnosti (VR) i mješovite stvarnosti (MR) u kontekstu skladišnog poslovanja. Ove tehnologije omogućavaju brže i preciznije planiranje ukrcaja, bolju vizualizaciju prostora skladišta i optimizaciju rasporeda tereta. Također, pružaju mogućnost za trening zaposlenika kroz simulirane scenarije, što rezultira smanjenjem pogrešaka i povećanjem produktivnosti. Osim toga, rad se osvrće na ulogu "big data" i umjetne inteligencije (AI) u unapređenju procesa. Korištenjem velikih skupova podataka i naprednih analitičkih alata, kompanije sada mogu bolje predviđati trendove, pratiti i optimizirati rute prijevoza, kao i precizno planirati kapacitete. Umjetna inteligencija, s druge strane, omogućava automatizaciju određenih procesa, predikciju potreba i personalizirano prilagođavanje rješenja za svaku specifičnu situaciju.In modern business, information technologies (IT) play a pivotal role in optimizing various segments, especially in the sectors of loading and cargo transportation. This paper explores how IT technologies transform and enhance processes related to loading and transport, leading to greater efficiency compared to traditional methods that did not utilize IT. A key aspect of this paper is the analysis of the use of augmented reality (AR), virtual reality (VR), and mixed reality (MR) in the context of warehouse operations. These technologies enable faster and more accurate planning of loading, better visualization of warehouse spaces, and optimization of cargo arrangements. Additionally, they provide opportunities for employee training through simulated scenarios, resulting in a reduction of errors and an increase in productivity. Furthermore, the paper touches upon the role of "big data" and artificial intelligence (AI) in process improvement. Using vast datasets and advanced analytical tools, companies can now better predict trends, monitor and optimize transport routes, and accurately plan capacities. Artificial intelligence, on the other hand, facilitates the automation of certain processes, predicts needs, and tailors solutions for every specific situation
Measurements of the optical communication system for port video surveillance
No full textOvaj se rad bavi detaljnom analizom i mjerenjem optičkog komunikacijskog sustava koji se koristi za video nadzor luke. Optičke niti predstavljaju suvremeno rješenje koje nudi brojne prednosti u usporedbi s tradicionalnim bakrenim kablovima, kao što su veća brzina prijenosa podataka, otpornost na elektromagnetske smetnje i veća sigurnost. Pri tome se ukazuje na različite aspekte optičkih komunikacijskih sustava, uključujući vrste optičkih vlakana, njihove karakteristike i načine spajanja. Posebna pažnja posvećena je tehnologijama spajanja vlakana, budući da kvaliteta spajanja značajno utječe na ukupne performanse sustava. Detaljno su opisane metode mjerenja performansi optičkih sustava, s posebnim naglaskom na korištenje OTDR (engl. Optical Time-Domain Reflectometer) uređaja. OTDR uređaji omogućuju precizno mjerenje dužine optičkog vlakna, otkrivanje gubitaka signala i identifikaciju kvarova duž vlakna.This paper deals with the detailed analysis and measurement of the optical communication system used for video surveillance of ports. Optical fibers represent a modern solution that offers numerous advantages compared to traditional copper cables, such as higher data transmission speed, resistance to electromagnetic interference and greater security. Various aspects of optical communication systems are presented, including types of optical fibers, their properties and connection methods. Particular attention is paid to fiber splicing technologies, as the quality of the splice has a significant impact on the overall performance of the system. Methods for measuring the performance of optical systems are described in detail, with a focus on the use of OTDR (Optical Time-Domain Reflectometer) devices. OTDR devices allow precise measurement of the length of the optical fiber, detection of signal loss and identification of faults along the fiber
Advanced microprocessor architecture
No full textCilj ovog završnog rada je prikazati napredne arhitekture mikroprocesora. U prvom
poglavlju opisano je što je integrirani krug i kako je nastao. Osim toga, navodi se kako se
integrirani krugovi mogu klasificirati ovisno o vrsti signala, kućištu ili stupnju integracije.
Također, u prvom poglavlju opisan je povijesni razvoj mikroprocesora koji je podijeljen na
pet generacija. Za svaku generaciju opisano je razdoblje trajanja, koji modeli
mikroprocesora su bili značajni za to razdoblje i koja su tehnološka postignuća ostvarena.
U drugom poglavlju uz pomoć općeg modela mikroprocesora opisani su dijelovi
mikroprocesora, a to su: aritmetičko-logička jedinica, upravljačka jedinica i registarski
skup. Za kraj drugog poglavlja, opisan je princip rada mikroprocesora tijekom izvođenja
programa. U trećem poglavlju opisane su arhitekture CISC i RISC koje se nalaze u
današnjim mikroprocesorima te njihov princip rada. Osim toga, opisano je nekoliko
tehnologija koje se koriste kod današnjih mikroprocesora poput: višejezgreni procesori,
hiperdretvenost, turbo ubrzanje i sl.The goal of this undergraduate thesis is to present advanced architectures of
microprocessors. The first chapter describes what an integrated circuit is, how it was
created. and how integrated circuits can be classified depending on the type of signal,
package or degree of integration. Also, the historical development of the microprocessor is
described, which is divided into five generations. For each generation, the period of
duration is described, as well as significant microprocessor models and technological
achievements. In the second chapter, using the general microprocessor model, the parts of
the microprocessor are described, namely: arithmetic-logic unit, control unit and register
set. At the end of the chapter, the work principle of microprocessor during program
execution is described. The third chapter describes the CISC and RISC architectures found
in today's microprocessors and their operating principles, and several technologies used in
today's microprocessors such as: multicore processors, hyperthreading, turbo boost and etc
Corpus-based analysis of potential hedges in maritime legal texts in English
No full textOgrade (engl. hedges) su epistemički jezični elementi kojima se ublažavaju kategoričke tvrdnje, odnosno izražava mogućnost, nesigurnost, neodređenost ili stupanj opredijeljenosti govornika ili autora teksta prema istinitosti iskaza. Jezično ograđivanje jedna je od temeljnih značajki znanstvenog diskursa. No, isto tako, ograđivanje se javlja i u specijaliziranim tekstovima pravnog diskursa, u kojima ovakvi epistemički izrazi obavljaju specifične komunikacijske i žanrovske funkcije. U radu su prikazani rezultati istraživanja jezičnih sredstava koja mogu potencijalno vršiti funkciju ograda u pomorskopravnim tekstovima na engleskom jeziku, pri čemu je analiza provedena na jezičnom korpusu sastavljenom od četiriju pomorskopravnih tekstova. Tekstovi obuhvaćaju dvije međunarodne konvencije, jedan pravilnik i jedan kodeks. Na temelju popisa potencijalnih leksičkih ograda i strategija ograđivanja do sada zabilježenih u prethodnim sličnim istraživanjima, provedena je kvantitativna analiza s pomoću računalno-jezikoslovnog alata Sketch Engine te su ponuđeni i kvalitativno analizirani odabrani primjeri ograda iz korpusa. Najčešće potencijalne leksičke ograde zabilježene u korpusu jesu epistemički modalni glagoli, dok su od potencijalnih strategija najznačajnije pogodbene rečenice i pasiv. Ograde se koriste kao tekstualna sredstva za izražavanje (ne)preciznosti, ograničavanje opsega primjene pravnih propisa i ublažavanje stava prema istinitosti ili vjerojatnosti iskaza te impliciraju da određeni iskaz nije utemeljen na pouzdanom znanju, već plauzibilnom i/ili hipotetičkom rasuđivanju.Hedges are epistemic linguistic devices that mitigate categorical claims by expressing the possibility, uncertainty, vagueness, or a degree of commitment of the speaker or author of the text towards the truth value of the proposition. Previous research has shown that hedges are one of the fundamental features of scientific discourse. Howe¬ver, hedges also occur in legal discourse, in which such epistemic expressions perform specific communicative functions. The paper presents the results of the analysis of po¬tential hedges carried out on a corpus of four maritime legal texts written in English. The texts include two international conventions, one set of regulations, and one code. Based on the list of potential lexical hedges and hedging strategies identified in previ¬ous similar research, a quantitative analysis was carried out using the Sketch Engine tool and examples of actual hedges were extracted from the corpus and analysed quali¬tatively. The most common potential lexical hedges recorded in the corpus are epistemic modal verbs, while the most significant potential hedging strategies are con¬ditional clauses and the passive voice. Hedges are used to express (im)precision, limit the legal scope, and soften the author’s commitment to the truth value or probability of a proposition, implying that a particular statement is not based on reliable knowled¬ge, but rather on plausible and/or hypothetical reasoning
Analysis of Beaches and Beach Managing in Context of New Maritime Domain and Sea Ports Act
No full textBeaches are a resource that often captures public interest, especially in local communities, due to the various roles they play in people's lives. Interest in beaches is continuous and diverse, while the pressure on them is increasing. Economic interest, as a result of tourist demand, is evident both globally and in Croatia. Simultaneously, there is a growing interest in beaches among the experts and scientists, considering various issues, including the economic impacts on beaches and their effects on the environment. Although various laws and directives regulate the management and protection of beaches as a resource, the approaches vary. In 2023, the Croatian Parliament amended a new Maritime Domain and Sea Ports Act (MDSPA), which introduces different approaches to beaches beyond their classification.
The subject of this research is beaches in general, and open questions in the new legal framework. The purpose of the research is to analyse the institutional framework and how beaches are managed in Croatia. The authors analyse the new legal solutions in MDSPA, explaining the jurisdiction, form of using and managing, protection, and the economic use of beaches. The aim of the research is to analyse the theoretical and legal aspects of beaches, identify open questions, propose methodology and measures to improve the beach managing model in Croatia
Improved estimation of exhaust gases emission factors in the ship's real-time exploitation conditions
No full textIstraživanje u ovom doktorskom radu obuhvaća područje emisija ispušnih plinova iz brodskih dizelskih motora i problematiku procjene količine emisija. Kvantifikacija emisija iz brodskih postrojenja predstavlja izazov prilikom izrade inventara emisija za pomorski promet. Jedna od najvažnijih varijabli prilikom izračuna ukupne količine emisija je emisijski faktor za određene ispušne plinove. Emisijski faktori ovise o parametrima kao što su vrsta korištenog goriva, karakteristike pogonskih i pomoćnih motora, opterećenje motora i kvaliteta procesa izgaranja. U radu je provedeno istraživanje na tri Ro-Pax broda koji plove na području Jadranskog mora između luka Hrvatske, Italije i Crne Gore. Istraživanje uključuje mjerenja koncentracije ispušnih plinova na brodovima u stvarnim uvjetima eksploatacije prilikom različitih aktivnosti broda. Mjerenja su izvršena s Testo 350 Maritime v2 uređajem za mjerenje sastava ispušnih plinova, te je prikupljena CO2 i NOx baza podataka u fazama plovidbe i manevriranja. Rezultati mjerenja predstavljaju emisije ispušnih plinova iz glavnih motora ovisno o opterećenju motora i aktivnosti broda. Nakon procesa mjerenja i prikupljanja baze podataka, podaci su obrađeni s metodom strojnog učenja koristeći Gaussovu nelinearnu regresiju, gdje CO2 i NOx varijable ovise o opterećenju glavnih motora, temperaturi ispušnih plinova i udjelu kisika u ispušnim plinovima, što predstavlja tri nezavisne varijable. Rezultati modeliranja su prikazani na dijagramima gdje su uspoređene izmjerene vrijednosti s procijenjenim vrijednostima. Optimizacija modela ovisi o izboru odgovarajuće kovarijance, te su dobiveni CO2 i NOx modeli optimizirani u fazama plovidbe i manevriranja, što je prikazano s visokim koeficijentom determinacije. Nadalje, predloženi modeli omogućavaju odabir emisijskih faktora ovisno o onečišćivaču, opterećenju motora i aktivnosti broda. Procijenjeni emisijski faktori uspoređeni su s emisijskim faktorima iz relevantnih studija inventara emisija, gdje su opisane njihove prednosti i mogućnosti upotrebe. U rad je dokazana korelacija između emisijskih faktora i promjenjivih uvjeta eksploatacije, te predloženi modeli omogućavaju vjerodostojnije CO2 i NOx emisijske faktore od trenutno dostupnih. Upotrebnom adekvatnih emisijskih faktora moguće je unaprijediti procjenu ukupnih emisija iz brodskih postrojenja, te su predložene dodatne mogućnosti unapređenja istraživanja na ovu temu.The research in this doctoral thesis covers the area of exhaust gas emissions from marine diesel engines and the problem of estimating the amount of emissions. The quantification of emissions from ship powerplant is a challenge when creating an emissions inventory for maritime transport. One of the most important variables when calculating the total amount of emissions is the emission factor for certain exhaust gases. Emission factors depend on parameters such as the type of used fuel, the characteristics of the main and auxiliary engines, the engine load and the quality of the combustion process. In the thesis, research was carried out on three Ro-Pax ships sailing in the area of the Adriatic Sea between the ports of Croatia, Italy and Montenegro. The research includes measurements of the concentration of exhaust gases on ships in real-time exploitation conditions during various ship activities. Measurements were conducted with a Testo 350 Maritime device for measuring the content of exhaust gases, and a CO2 and NOx database was collected during the cruising and maneuvering phases. The measurement results represent exhaust gas emissions from the main engines depending on the engine load and the ship's activity. After the measurement and database collection process, the data was processed with the machine learning method using Gauss nonlinear regression, where the CO2 and NOx variables depend on the load of the main engines, the exhaust gas temperature and the oxygen content in the exhaust gas, which represents three independent variables. The modeling results are shown in diagrams where the measured values are compared with the estimated values. The optimization of the model depends on the choice of the appropriate covariance, and the obtained CO2 and NOx models were optimized in the cruising and maneuvering phases, which was indicated with a high coefficient of determination. Furthermore, the proposed models enable the selection of emission factors depending on the pollutant, engine load and ship activity. The estimated emission factors were compared with the emission factors from the relevant emissions inventory studies, where their advantages and possibilities of use were described. The correlation between emission factors and variable exploitation conditions was proven in the thesis, and the proposed models enable more reliable CO2 and NOx emission factors than currently available. By using adequate emission factors, it is possible to improve the estimation of total emissions from ship powerplants, and additional possibilities for improving research on this topic are proposed
Modeling of Actuation Force, Pressure and Contraction of Fluidic Muscles Based on Machine Learning
No full textIn this paper, the dataset is collected from the fluidic muscle datasheet. This dataset is then used to train models predicting the pressure, force, and contraction length of the fluidic muscle, as three separate outputs. This modeling is performed with four algorithms—extreme gradient boosted trees (XGB), ElasticNet (ENet), support vector regressor (SVR), and multilayer perceptron (MLP) artificial neural network. Each of the four models of fluidic muscles (5-100N, 10-100N, 20-200N, 40-400N) is modeled separately: First, for a later comparison. Then, the combined dataset consisting of data from all the listed datasets is used for training. The results show that it is possible to achieve quality regression performance with the listed algorithms, especially with the general model, which performs better than individual models. Still, room for improvement exists, due to the high variance of the results across validation sets, possibly caused by non-normal data distributions