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Determination od the exhaust gases composition of an aircraft piston engine in flight
No full textObzirom na zaštitu okoliša i klimatske promjene, napori ljudske vrste usmjereni su ka smanjenju koncentracije ispušnih plinova u atmosferi. U ovom radu će biti opisan rad i mogućnost korištenja sustava za mjerenje ispušnih plinova zrakoplovnog klipnog motora pomoću sustava PEMS (Portable Emission Measurment System). Taj sustav se već uspješno koristi na većini strojeva i vozila, a prednost njegova korištenja je što omogućava praćenje i mjerenje ispušnih plinova tijekom rada samog stroja ili vozila. Time je omogućena bolja slika i vidljivost podataka koji se ne mogu dobiti u laboratorijskim istraživanjima. U literaturi nisu pronađeni zapisi o mjerenju ispušnih plinova zrakoplovnih motora pomoću ovog sustava te se u ovom radu opisuje prijedlog ugradnje sustava PEMS na zrakoplove s klipnim motorom.With the goal of environment protection and climate change, human efforts are directed towards reducing the concentration of exhaust gasses in the atmosphere. This thesis will present the ability and work in using the system for exhaust gas measurment with the usage of the PEMS (Portable Emission Measurment System) system. The system has already been successfully used on the majority of ground machines and vehicles, and its advantage is the ability of measurment and study of the exhaust gases during the work of the vehicle or the machine, which allowes better perception of the data which can't be received in laboratory experiments. Although, there aren't any written examples of exhaust gas measurments of aircraft using the system, so this thesis will describe an attempt at the usage of the PEMS system onto the piston engine aircraft
Analysis of e distribution System-Case Study
No full textRazvoj e – trgovine u posljednjih desetak godina doživio je značajn skok. Sve više ljudi se okreće kupovini proizvoda, roba, usluga i informacija putem interneta, pomoću pametnih telefona i tableta. To sve dovodi do novih logističkih izazova, od koji je najbitnije spomenuti brzu dostavu uz najniže troškove. U ovom radu opisan je proces od narudžbe proizvoda do dostave paketa na kućnu adresu u sklopu tvrtke dm Hrvatska koja također posluje i putem online shopa-a. Analiziran je logistički sustav dm online shopa, manipulacija u skladištu, pakiranje proizvoda te dostava putem vanjskog dostavljača. Prikazan je sustav koji se koristi unutar skladišta te mogući prijedlozi unaprijeđenja sustava.The development of e-commerce in the last ten years has seen a significant jump. More and more people are turning to buying products, goods, services and information online, using smart phones and tablets. Therefore, logistics faces new problems such as fast delivey at the lowest cost. This paper describes the proces from product order to delivery od package to home adress within the company dm Hrvatska, which also operates via an online shop. The logistics system od dm online shop, warehousing, manipulation, packaging of products and delivery via external suppliers were analysed in this paper. The system used in the warehouse and possible suggestions for system improvement are presented
Fleet Management of Electric Mopeds in Intelligent Transport Systems
No full textTehnologija pogona električnih mopeda je znatno drugačija u odnosu na klasične mopede, te dolazi sa svojim pozitivnim i negativnim stranama. Upravljanje flotom električnih mopeda specifično je u odnosu na klasične mopede pogonjene otto-motorima. Takav inovativni koncept donosi svoje prednosti, ali i ograničenja u eksploataciji. U ovom završnom radu analiziran je koncept upravljanja flotom električnih mopeda.The technology that powers electric mopeds differs significantly compared to classic mopeds, and comes with its positive and negative sides. Fleet management of electric mopeds is specific in relation to classic propulsion mopeds. Such an innovative concept brings its advantages, but also limitations in exploitation. In this final paper, the concept of fleet management of electric mopeds is analyzed
Data Transfer Technology in 5G Mobile Networks
No full textU ovom radu obrađena je tema razvojnog puta mobilnih mreža s naglaskom na posljednju, odnosno petu generaciju mobilnih mreža. Mobilne mreže su tijekom posljednjih nekoliko desetljeća doživjele veliki napredak. Kategorizirane su po generacijama, a svaka od njih je nastala kao nadogradnja na prethodnu. Pojedinačno su obrađene prva, druga, treća i četvrta generacija mobilnih mreža. Za svaku od generacija navedene su specifikacije te nadogradnje koje su učinjene u odnosu na prethodnu generaciju. Fokus ovog rada usmjeren je na petu generaciju mobilnih mreža, a shodno tome je razrađen njen razvoj, ali i specifikacije, mrežna arhitektura te naposljetku korištenje na globalnoj razini. Slijedom navedenog, objašnjena je tehnika multipleksiranja te neki od tipova multipleksiranja koji se koriste u 5G mreži. Nadalje, obrađene su tehnike prijenosa podataka, kao i uporaba antenskih nizova i pametnih antena koje su od izuzetne važnosti za 5G mrežu.This paper deals with the topic of the development of mobile networks with an emphasis on the last, fifth generation of mobile networks. Mobile networks have experienced great progress over the last few decades. They are categorized by generations, and each of them was created as an upgrade to the previous one. The first, second, third and fourth generation of mobile networks are processed individually. For each of the generations, the specifications and upgrades made in relation to the previous generation are listed. The focus of this paper is on the fifth generation of mobile networks, and its development is elaborated, as well as its specifications, network architecture and lastly its use on a global level. Following the above, the multiplexing technique and some of the types of multiplexing used in the 5G network are explained. Furthermore, data transmission techniques are covered, as well as the use of antenna arrays and smart antennas that are of utmost importance for the 5G network
Application of Antenna Arrays for Directional Communication in 5G Systems
No full textRazvojem tehnologije i sve većom potrebom za velikim kapacitetom mreže, antene koje su se koristile za dosadašnje komunikacije više nisu dostatne. Komunikacije u milimetarskom frekvencijskom spektru omogućile su smanjenje fizičkih dimenzija antena i tako su nastali antenski nizovi koji mogu postići veliki kapacitet i efikasnost kanala. Tehnikama prostornog diverzitija smanjeni su utjecaji fedinga i količina generiranih grešaka u urbanim sredinama. Kako bi komunikacija između mobilni uređaji i bazne stanice bila moguća, mobilni uređaji moraju biti opremljeni posebno dizajniranim antenskim nizovima koji zadovoljavaju proporcije pametnih uređaja i baznih stanica. Zbog nemogućnosti odašiljanja signala na velike udaljenosti, bazne stanice moraju biti efikasno dizajnirane da se uklope u ljudsko okruženje.With the development of technology and the growing need for large network capacity, the antennas used for previous communications are no longer sufficient. Communications in the millimeter frequency spectrum have made it possible to reduce physical dimensions of the antennas and thus have created antenna arrays that can achieve high channel capacity and efficiency. Spatial diversity techniques have reduced the impacts of fading and the amount of errors generated in urban areas. For communication between mobile devices and the base stations to be possible, cellular devices must be equipped with specially designed antenna arrays that meet the proportions od smart devices and base stations. Due to the inability to transmit signals over long distances, base stations must be efficiently designed to fit into human environment
Geografical and Traffic Analysis of the Adriatic-Ionian Highway
No full textCestovni promet je najrazvijeniji i najvažniji oblik prometa kojim se prevozi najviše robe i putnika. Jadransko-jonska autocesta je najznačajniji gospodarski projekt čiji su dijelovi izgrađeni u Hrvatskoj te prolazi kroz sedam zemalja čiju gradnju smatramo jednim od najvećih investicijskih i građevinskih poduhvata ikad ostvarenih u Hrvatskoj. Također imamo i jedan vrlo bitan dio cestovne mreže koridora Jadransko-jonske autoceste, a to je most Pelješac čijom se izgradnjom žele riješiti prometni problemi na području Dubrovačko-neretvanske županije te je on ujedno i najvažnija investicija u novom vremenu. Jako bitan je i Jadransko – jonski koridor jer ima važan utjecaj na zemlju kako zbog gospodarstva, tako i zbog turizma koji je cilj naše turistički aktivne regije.A road traffic is the most developed and the most important form of transport by which the most goods and passengers are transported. The Adriatic-Ionian highway is the most important economic project whose parts are built in Croatia and who is going through seven countries whose construction we consider to be one of the largest investment and construction projects ever made in Croatia. We also have a very important part of a road network of the corridor of the Adriatic-Ionian highway which is Pelješac Bridge, whose construction is trying to solve traffic problems in the area of Dubrovnik-Neretva County and is also the most important investment in a new era. The Adriatic-Ionian corridor is also very important because it has an important impact on the country both for economic and for tourism, which is the goal of our tourism-active region
Combustion chambers of aircraft jet engines with low levels of nitrogen oxide pollution
No full textZračni promet ima značajne posljedice na okoliš u cijelom svijetu, uključujući i posljedice na klimu. Emisije ispušnih plinova mlaznih zrakoplova talože se izravno u gornju atmosferu, a neke zagrijavaju atmosferu više od plinova ispuštenih bliže površini. Emisije, osobito emisije NOX, jedan su od primarnih problema komora izgaranja zrakoplovnih mlaznih motora. Kontrola emisija dušičnog oksida u zrakoplovnim mlaznim motorima može se izvesti pomoću različitih pristupa. U ovom završnom radu analizirane su tehnologije s najvećim potencijalom za smanjenje emisije NOx u zrakoplovnim mlaznim motorima.Air transportation has significant environmental impacts worldwide, including climate impacts. Jet exhaust emissions are deposited directly into the upper atmosphere, and some of them warm the atmosphere more than gases emitted closer to the surface. Emissions, especially NOX emissions, are one of the primary problems of combustion chambers of aircraft jet engines. Control of nitrogen oxide emissions in aircraft jet engines can be perfomed using variety of approaches. In this final paper, the tehnologies with the greatest potential for reducing NOX emissions in aircraft jet engines are analyzed
Accuracy Check of Air Pressure Measuring Instruments of the Zlin 242L Aircraft
No full textSvrha ispitivanja točnosti tlakomjernih instrumenata je provjera funkcionalnosti instrumenata te njihovih eventualnih odstupanja. U ovom završnom radu analizirani su zrakoplovni tlakomjerni instrumenti. U suradnji sa Zrakoplovno-tehničkom bojnom provedeno je ispitivanje točnosti brzinomjera, visinomjera i variometra na zrakoplovu Zlin 242L registarske oznake 401, koji je u uporabi u Hrvatskom ratnom zrakoplovstvu. Analiza rezultata provjere točnosti pokazala je da su pogreške instrumenata unutar dozvoljenih granica te da je zrakoplov, obzirom na taj kriterij i dalje operativan.The purpose of testing the accuracy of pressure gauges is to check the functionality of the instruments and their possible deviations. In this final paper, aircraft pressure gauges are analyzed. In cooperation with the Aeronautical Technical Battalion, the accuracy of air speed indicator, altimeter and vertical speed indicator was tested, and an analysis of the accuracy check results was made. The accuracy check was performed on a Zlin 242L aircraft with registration number 401, which is in use in the Croatian Air Force. The results of the accuracy check showed that the errors of the instruments were within the permitted limits and that the aircraft was still operational, given this criterion
Airplane Load Factor Calculation during a Turn in the Horizontal Plane
No full textGlavna uloga bilo kakvog zaokreta u zrakoplovstvu je promjena pravca leta. U praksi se primjenjuju različiti zaokreti u ovisnosti od potrebitih manevara zrakoplova. U ovom radu je detaljno objašnjen zaokret aviona u horizontalnoj ravnini, standardni horizontalni zaokret, faktor opterećenja i utjecaj faktora opterećenja na kretanje aviona po horizontalnoj putanji. Objašnjena je manevarska envelopta leta kao i njeno korištenje. U nastavku su nabrojane i navedene karakteristične pogreške upravljanja avionom u zaokretu.Kasnije su proračunate karakteristične vrijednosti parametara u zaokretu za avione Zlin 242-L i Pilatus PC-9, te je objašnjena njihova međuzavisnost.The main role of any turn in aviation is to change the direction of flight. In practice, different turns are applied depending on the required maneuvers of the aircraft. This paper explains in detail the turn of the aircraft in the horizontal plane, the standard horizontal turn, the load factor and the influence of the load factor on the movement of the aircraft over the horizontal path. The maneuvering envelope of the flight is explained as well as its usage. Furthermore, there are listed characteristical mistakes of steering the aircraft in a turn. Lastly, the characteristical values of the parameters in a turn are calculated for airplanes Zlin 242-L and Pilatus PC-9, and their interdependence is explained
Role of Key Protocols in IP Networks
No full textOvaj završni rad bavi se nekim od najistaknutijih protokola koji egzistiraju unutar IP mreže, poput DNS (Domain Name System), TCP (Transmission Control Protocol), NAT (Network Address Translation), OSPF (Open Shortest Path First). Kako bi se došlo do same srži teme odnosno protokola u IP mrežama, potrebno je sustavno pogledati na mrežu. Prvi od sustavnih koraka koji je dio ovog rada, a vodi do središta, je mreža širokog područja – WAN mreža. Unutar ranije spomenute mreže je sljedeća razina, odnosno LAN mreža. Kako su LAN mreže prilično širok i složen pojam, topologija LAN mreže će pomoći kako bi se raščlanili i na neki način rasporedili uređaji u mreži. Nadalje, obrada ove tematike teško je moguća bez da se spomene OSI model. Kada je riječ o tom modelu riječ je zapravo o arhitekturi mreže, apstraktnoj. U ovom završnom radu govori se i o napadima na LAN mreže, ali i mehanizmima koji se primjenjuju kako bi se promet podataka u LAN okruženju zaštitio.This bachelor’s thesis deals with some of the most prominent protocols that exist within an IP network, such as DNS (Domain Name System), TCP (Transmission Control Protocol), NAT (Network Address Translation), OSPF (Open Shortest Path First). To get to the core of the topic or protocol in IP networks, it is necessary to look systematically at the network. The first of the systematic steps that is part of this paper and leads to the centre is a wide area network - WAN network. Within the previously mentioned network is the next level, ie the LAN network. As LANs are a rather broad and complex concept, a LAN topology will help to break down and somehow arrange devices in a network. Furthermore, the treatment of this topic is hardly possible without mentioning the OSI model. When it comes to this model, it is a network architecture, albeit an abstract one. This bachelor’s thesis also discusses attacks on LAN networks, but also the mechanisms used to protect data traffic in a LAN environment