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Logistics and logistics processes in correlation with sustainable business
No full textLogistika uključuje upravljanje tokovima roba, usluga i informacija od proizvodnje do krajnjeg korisnika. Logistički procesi imaju određena štetna djelovanja, najviše na okoliš, a time i na čovjeka i gospodarstvo, zbog čega se uvodi održivo poslovanje u poduzeća. U završnom radu nastoji se definirati pojmove logistike, logističkih procesa, održivosti i održivog razvoja, te objasniti sve usko povezane pojmove. Cilj završnog rada je analizirati i dobiti uvid o negativnim utjecajima logističkih procesa i načinima na koje ih poduzeća nastoje smanjiti. Nabrojani su i objašnjeni najvažniji elementi i značajke održivosti. Također su osim teorijskih pojmova i definicija analizirani primjeri iz prakse – DHL, UPS i IKEA, te načini na koje se navedena poduzeća trude smanjiti negativan utjecaj, a pritom ostati konkurenti.Logistics involves the management of the flow of goods, services, and information from production to end-users. Logistic processes have certain harmful effects, primarily on the environment, and thereby on people and the economy, which is why sustainable business practices are being introduced into companies. This final paper aims to define the concepts of logistics, logistic processes, sustainability, and sustainable development, and explain all closely related terms. The goal of the final paper is to analyze and gain insight into the negative impacts of logistic processes and the ways in which companies try to reduce them. The most important elements and features of sustainability are listed and explained. In addition to theoretical concepts and definitions, practical examples are analyzed - DHL, UPS, and IKEA, and the methods these companies employ to reduce their negative impact while remaining competitive
Features of traditional and ECDIS-based voyage planning
No full textEvolucija planiranja pomorskog putovanja donijela je značajnu promjenu u tradicionalnom
oslanjanju na papirnate pomorske karte do modernog doba ECDIS sustava i elektroničkih
navigacijskih karata. Ova transformacija temeljno je promijenila način na koji pomorci
planiraju putovanje brodom. Iako papirnate karte imaju dugu povijest i služe kao pouzdana
osnova, ECDIS, opremljen elektroničkim kartama i naprednim informacijskim sustavima,
donio je niz prednosti. ECDIS ne samo da pruža stvarno vrijeme pozicioniranja, već nudi i
dinamičko planiranje, sigurnost te integraciju vitalnih navigacijskih podataka. Kroz ovaj rad
prikazan je proces planiranja putovanja općenito, dok su specifičnosti planiranja putovanja
tradicionalnim načinom i uz pomoć ECDIS sustava opisana pojedinačno. Značajke u vidu
prednosti i mana oba načina također su prikazane te se može se reći da su papirnate pomorske
karte i tradicionalni način planiranja pomorskog putovanja i dalje sveprisutni u pomorskoj
navigaciji te čine temelj i osnovu razvoja ECDIS sustava i elektroničkih navigacijskih karata.The evolution of maritime voyage planning has brought about a significant change, shifting from traditional reliance on paper nautical charts to the modern era of ECDIS and electronic navigation charts. This transformation has fundamentally altered how mariners plan their ship voyage. While paper charts have a long history and serve as a reliable foundation, ECDIS, equipped with electronic charts and advanced information systems, has introduced a range of advantages. ECDIS not only provides real-time positioning but also offers dynamic route planning, safety features, and integration of vital navigational data. This final work shows the process of passage planning in general, while the specificities of planning in the traditional way and using ECDIS are described individually. Features in terms of advantages and disadvantages of both methods are also presented and it can be said that paper nautical charts and the traditional approach to maritime voyage planning remain pervasive in maritime navigation, serving as the foundation and basis for the development of ECDIS systems and electronic navigation charts
Numerical protection relay
No full textU brodskom elektroenergetskom sustavu pojava kvara ima za posljedicu ozbiljne prekide u snabdijevanju električnom energijom i direktno utječe ne sigurnost posade i broda. Zbog toga je nužno realizirati sustave električnih zaštita koji će omogućiti da se utjecaj kvara u sustavu svede na takvu mjeri, da ne nastanu štetne posljedice većeg obujma ni na postrojenjima niti bilo kakva opasnost po ljude. Ovo se može ostvariti jedino na taj način što će se usvojiti odgovarajuća koncepcija zaštite, sa brižljivo odabranim elementima, koja će neprestano pokrivati proizvodne, prijenosne i distributivne sustave. Tema ovog rada su numerički zaštitni releji kao ključne komponente za realizaciju naprednih sustava električnih zaštita u modernim brodskim elektroenergetskim mrežama.In the ship's electrical power system, the occurrence of a malfunction results in serious interruptions in the supply of electricity and directly affects the safety of the crew and the ship. For this reason, it is necessary to implement electrical protection systems that will enable the impact of a malfunction in the system to be reduced to such an extent that there are no large-scale harmful consequences for plants or any danger to people. This can only be achieved by adopting a suitable protection concept, with carefully selected elements, which will continuously cover the production, transmission and distribution systems. The topic of this paper is numerical protective relays as key components for the implementation of advanced electrical protection systems in modern marine electrical power grids
Telemetry and measuring systems
No full textTema ovog završnog rada je daljinska mjerenja i mjerni sustavi. Mjerenje igra ključnu ulogu u mehatroničkim sustavima, jer omogućuje prikupljanje vitalnih informacija o stanju sustava. Glavna svrha mjernih sustava jest prikupljanje podataka o stanju sustava i njihova obrada radi upravljanja cijelim sustavom. Daljinsko mjerenje u nekim knjigama može se susresti pod nazivom telemetrija. Daljinsko mjerenje ima veliku ulogu u svakodnevnome životu svih ljudi te zadire u većinu znanosti o Zemlji, poput geologije, hidrologije, meteorologije, ekologije, zemljopisa... Daljinsko mjerenje koristi se i u vojne svrhe te mnoge druge. Razvijanjem novih tehnologija napreduje također i sama tehnologija daljinskoga mjerenja te se onda stalno mijenja i nadograđuje.The topic of this final paper is remote measurement and measuring systems. Measurement is one of the most important subsystems that goes under mechatronic system. One of the most important and the main role of measuring system is gathering data about the system which are delivered to the microprocessors so they can control the entire system. Remote measurement is also known as telemetry. It has an important role in the everyday life of every human, and it relates to most of the science disciplines such as: geology, hydrology, meteorology, ecology, geography, oceanography, it is also being used for military purposes and many others. As the technology itself is advancing so is the technology of remote measurement, it is being changed and upgraded constantly
Overview of technologies for the exploitation of sea waves and the possibility of their application in the Republic of Croatia
No full textPovijest uređaja za iskorištavanje energije valova obilježena je napretkom, izazovima i istraživanima koja su u tijeku. Iako je komercijalna implementacija ograničena, potraga za načinom iskorištavanja energije valova ostaje aktivno područje, s ciljem razvoja održivih i pouzdanih rješenja za obnovljivu energiju iz snage valova. U radu je dan pregled tehnologija iskorištavanja energije valova s naglaskom na mogućnosti primjene u Republici Hrvatskoj. Rad započinje opisom osnovnih značajki energije valova i njihove upotrebe u svijetu. Nadalje su u radu opisane tehnologije uzimajući u obzir ključna pitanja njihovih prednosti, nedostataka i ograničenja. Metodologija istraživanja uključuje pregled literature, analizu podataka i studija slučaja postojećih projekata. Za lokaciju u blizini otoka Palagruže napravljena je analiza i usporedba uređaja Archimedes Waveswing, AquaBuoy i Wave Dragon. Rad također istražuje potencijalnu mogućnost umrežavanja s postojećim objektima kako bi se povećala učinkovitost i smanjili troškovi rada.The history of wave energy devices is marked by progress, challenges, and ongoing research. Although commercial implementation is limited, the search for a way to harness wave energy remains an active field, with the aim of developing sustainable and reliable solutions for renewable energy from wave power. The thesis presents an overview of technologies for the use of marine energy with an emphasis on possibilities of application in the Republic of Croatia. The paper begins with a description of the basic characteristics of wave energy and its use in the world. Furthermore, the paper describes the technologies in terms of the direction of the incident wave and the mode of operation, considering the key issues of their strengths, weaknesses, and limitations. Research methodology includes literature review, data analysis and case studies of existing projects. An analysis and comparison of Archimedes Waveswing, AquaBuoy and wave Dragon was made for a location near the island of Palagruza. The work also explores the potential for networking with existing facilities to increase efficiency and reduce operating costs
Steering gear hydraulic system stuwa
No full textIako hidraulični sustavi zahtjevaju prilično preciznu izradu zbog tlakova koji djeluju unutar njih, princip rada im je prilično jednostavan. Osnova svakog hidrauličnog sustava je cilindar. Kormilo je na neki način centar broda jer određuje smjer u kojemu će se okrenuti naš pramac. Dok se do prije nekoliko godina plovilo na manjim brodicama bez hidraulike kormila, danas se ugrađuju pogonski strojevi velike snage i na manjim brodicama što je donijelo i potrebu za kvalitetnijom i tehnološki naprednijim sustavom upravljanja koji ne prestavlja samo pitanje komoditeta već i sigurnost.
Ovdje su nabrojani sastavni dijelovi ovog sustava, prikazan je sistem rada hidraulike i obrađeni su kvarovi koji se javljaju na hidrauličnom cilindru. Neki dijelovi sustava hidraulike su prikazani izvornim slikama. Svrha kormila je stvoriti poprečnu silu pomoću vode propelera ili uzdužnim vodom vode kako bi brod mogao manevrirati. Kormilo je dizajnirano da drži brod na kursu uz minimalan otpor.Although hydraulic system require quite precise manufacturing due to the pressures that act within them, their working principle is quite simple. The basis of every hydraulic system is a cylinder. The ruddern is in a way the center of the ship because it determines the direction in which our bow will turn. While until few years ago, smaller boats were sailed without hydraulic rudder, today high powered propulsion machines are also installed on smaller boats, which has brought the need for a higher quality and technologically advanced managementsystem that is not only a matter of convenience but also of safety.
The components of this system are listed here, the hydraulic system is shown, and malfunctions that occur on the hydraulic cylinder are discussed. Some parts of the hydraulic system are shown in the original pictures. The purpose of the rudder is to create transverse force using the water of the propeller or longitudinal water so that the ship can maneuver. The rudder is designed to keep the ship on course with minimal resistance
Electrical energy storage systems
No full textSkladišta električne energije su vrlo važna tehnologija za rješavanje problema proizvodnje i distribucije el. energije u današnjem svijetu, te je njihova primjena sve veća. Postoji mnogo različitih vrsta skladišta energije, što uključuje baterije, super kondenzatore, reverzibilne hidroelektrane, zamašnjaci, itd. Ovaj će se rad većinom fokusirati na baterijska skladišta električne energije. Unutar su istog opisane vrste baterijskih skladišta energije, njihov princip rada, prednosti i mane. Detaljno su opisani kriteriji vrednovanja skladišta energija kao što su učinkovitost, kapacitet, životni vijek, pouzdanost, sigurnost, troškovi, ekološki utjecaj, itd. Zatim je objašnjena primjena na brodovima, te način spajanja i upravljanje skladištima energije. Na kraju rada dan je zaključak o istraživanju te o mogućim budućim smjerovima ovih tehnologija.Electric energy storage is a highly important technology for solving the problem of electricity production and distribution. of energy in todays world, and their application is increasing. There are many different types of energy storage, including batteries, super capacitors, reversible hydroelectric power plants, flywheels, etc. This paper will mostly be focused on battery energy storage. It describes the types of battery energy storage, their working principle, and advantages and disadvantages. The evaluation criteria of energy storage are described in detail, such as efficiency, capacity, lifetime, reliability, safety, costs, environmental impact, etc. Then the application on ships, and the way of connecting and managing energy storage are explained. At the end of the paper, a conclusion is given on the research and on the possible future directions of these technologies
Passage planning optimization based on discrete global path planning methods
No full textGlobalno planiranje puta odnosi se na određivanje geometrijskog puta u statičkome i poznatome prostoru, najčešće koristeći diskretne metode i pripadajuće algoritme kojima se stvarno okružje pretvara u oblik prikladan za pretraživanje rješenja. Kako su osnovne metode i algoritmi globalnog planiranja puta proizašli iz teorije grafova, robotike, teorije upravljanja i automatizacije, njihova prilagodba značajkama klasičnog pomorskog planiranja uz korištenje elektroničkih navigacijskih karata nije dovoljno razmatrana. Vrlo skromne mogućnosti i složenost korištenja elektroničkih navigacijskih karata izvan osnovnog navigacijskog okružja i ograničenja trenutno važećih standarda otežavaju istraživačke pristupe i primjenu modernih tehnoloških rješenja, naročito besplatnih i otvorenog koda. Za navedene izazove u ovome doktorskome radu stvorena je metodologija koja se sastoji od nekoliko sastavnica. Prva se odnosi na unos, pohranu i prilagodbu objekata elektroničkih navigacijskih karata u objektno-relacijskoj bazi podataka koje se može prilagoditi prema navigacijskoj primjeni, području plovidbe ili vrsti objekta. Sljedeća sastavnica se odnosi na korištenje prostornih proširenja kojima je moguće modelirati prostor te ograničiti i ubrzati pretraživanje rješenja u plovidbenom području i odrediti globalni put. Uz navedeno, primijenjena su ograničenja i postupci prema standardnim postupcima iz planiranja putovanja, što je u prethodnim istraživačkim pristupima vrlo skromno razmatrano. Posljednja sastavnica odnosi se na korištenje podataka automatskog identifikacijskog sustava, statističke i usporedbe sličnosti putova korištenjem diskretne Fréchetove udaljenosti. Za primjenu diskretnih metoda razmatralo se područje između luka Savannah i Charleston u SAD-u. Prostor je modeliran korištenjem šesterokutnih H3 rešetki veličina definiranih odabranom rezolucijom dok je put određen korištenjem Dijkstrinog algoritma koji je pojednostavljen Ramer, Douglas i Peucker te Visvalingam i Whatt algoritmima, i izglađen Bsplajnovima. Obilježja određenog globalnog puta uspoređena su sa putovima stvarnih brodova i provjerena u navigacijskom simulatoru, čime je potvrđena primjenjivost metodologije u okružju pomorskog planiranja putovanja. U budućim istraživanjima razmotrit se će unapređenje određivanja, pojednostavljivanje i izglađivanje putova, korištenje većeg broja elektroničkih navigacijskih karata i pripadajućih objekata te primjena ostalih izvora navigacijskih podataka.Global path planning refers to the determination of the geometric path in static and known environment, most often using discrete methods and associated algorithms on the environment model suitable for searching of global path planning solutions. As the basic methods and algorithms of global path planning originate from graph theory, robotics, control theory and automation, their adaptation to the features of classical maritime voyage planning with the use of electronic navigational charts has not been sufficiently researched. The very modest possibilities and complexity of using electronic navigational charts outside the basic navigational environment and the limitations of currently valid standards makes the research and application of modern technological solutions difficult, notably free, and open source. For these challenges in this doctoral thesis, a methodology consisting of several components has been created. The first refers to importing, storing, and modification of electronic navigational chart objects in the object-relational database that can be adapted according to the navigational purpose, navigation area or type of an object. The following component refers to spatial extensions that can be used for environment modelling, limiting, and speeding up of solution search in the navigational area and determination of the global path. In addition, constraints and standard procedures from voyage planning have been applied, which has been very modestly considered in previous research approaches. The last component refers to the use of automatic identification system data, statistical and comparison of path similarities using discrete Fréchet distance. For the application of discrete methods, the area between the ports of Savannah and Charleston in the USA was considered. Static environment was modelled using hexagonal H3 grids defined by the selected predefined resolution. The path was determined using Dijkstra's algorithm and simplified with Ramer, Douglas and Peucker and Visvalingam and Whatt algorithms, further smoothed by B-splines. The characteristics of a particular global path were compared with the paths of actual ships and validated in the navigation simulator, which confirmed the applicability of the methodology in the maritime voyage planning environment. In future research, the improvement of path determination, simplification and smoothing will be considered, with use of larger number of electronic navigational charts with associated objects, along with the application of other navigational data sources
Bearings and their failures
No full textU ovom radu biti će pobliže opisani neki od ležajeva u brodskom sustavu te njihov značaj u funkcioniranju cijelog brodskog sustava. U početku rada pobliže opisujemo vrste i karakteristike ležajeva. U daljnjem tekstu detaljnije prikazujemo samim izborom materijala, nadalje način proizvodnje te moguće i potencijalne kvarove koji ne mogu dogoditi zasebno u razmatranju kliznih i Valjnih ležajeva. Također, pokušano je objasniti zašto se javlja trenje u ležajevima i na koje načine ga možemo smanjiti. U radu su spomenute neke vrste specifičnih ležaja
On Detection of Anomalous VHF Propagation over the Adriatic Sea Utilising a Software-Defined Automatic Identification System Receiver
No full textThis 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