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MAGNETIC PROPERTIES OF AMORPHOUS FERROMAGNETS
Get PDFProučavanje magnetskih svojstava amorfnih feromagneta vrlo je aktualno zbog njihove velike tehnološke primjene. U radu je ukratko opisana povijest magnetizma, dane su osnove teorije magnetizma s posebnim naglaskom na feromagnete, način proizvodnje amorfnih feromagneta te eksperimentalni postav za mjerenje magnetskih svojstava amorfnih feromagnetskih vrpci pomoću programa LabVIEW i Excel. Dan je i detaljan opis koda za usrednjavanje signala. ObraĎena je nastavna jedinica Elektromagnetska indukacija i Lenzovo pravilo.The study of the magnetic properties of amorphous ferromagnets is very actual because of many technological applications. This thesis briefly describes the history of magnetism, the fundamentals of theory of magnetism with special emphasis on ferromagnets, the method of production of amorphous ferromagnets and the experimental setup for measuring the magnetic properties of ferromagnetic amorphous ribbons using LabVIEW and Excel. In the end there is a detailed description of the LabVIEW's code for signal averaging. Finally, there is a teaching preparation on the subject of electromagnetic induction and Lenz's law
Doppler effect and everyday application
Get PDFU ovom radu prikazan je izvod Dopplerovog efekta te gotovi matematički modeli za pojedine
slučajeve pojave Dopplerova efekta. Također, navedeni su neki od najčešćih primjena
Dopplerova efekta u svakodnevnom životu bez detaljnog objašnjenja načina rada pojedine
tehnologije. Ovaj rad daje uvid u osnove o samoj pojavi i omogućava pojedincima da
samovoljno istraže detaljnije pojedinu primjenu ili matematički model.In this paper is shown Doppler effect and mathematical models for certain cases of Doppler
effect.Also it includes some of the most common application of Doppler's effect in everday life
without detail explanation of working principles behind individual technology that are presented.
This Thesis presents basic information about the phenomenon and allows individuals to research
the details of individual application or mathematical model by themself
Historical development of models of the universe
Get PDFoai:repozitorij.fizika.unios.hr:fizos_49U diplomskom radu opisani su različiti modeli svemira koji su se pojavljivali u prošlosti.
Početak interesa za prirodne pojave uz opis mitoloških slika svijeta drevnih civilizacija
(egipatske, babilonske i majanske) prikazan je u prvom dijelu rada. Zatim su opisani i
prokomentirani modeli svemira starogrčkih kao i srednjovjekovnih mislilaca sve do klasičnih
djela znanstvenika poput Isaaca Newtona i Williama Herschela. Opisane su i brojne ideje poput
one o beskonačnosti svemira, razmatranja o veličini i strukturi nebeskih objekata kao i o
udaljenostima među njima. Moderne metode proučavanja nebeskih pojava i današnje znanje o
strukturi svemira prikazane su u završnom dijelu rada.In this bachelor thesis models of the universe which appeared through the history are
described. The beginning of interest in natural phenomena and mythological pictures of the
world of ancient civilizations such as egyptian, babylonian and mayan are described in the first
part of thesis. Furthermore, the ancient greek and medieval universe models up to classical
approach of some great scientists such as Isaac Newton and William Herschel are described and
commented. Many ideas and hypothesis like infinite universe, considerations about size and
structure of heavenly bodies and distances between them are also shown and commented.
Modern methods of studying of heavenly bodies and today's knowledge about the structure of
Solar system and Universe itself are described in final part of this thesis
Measuring distances with ultrasound
Get PDFZvuk je longitudinalni val kojeg ljudi i životinje opažaju osjetilom sluha. Frekvencije
titranja zvuka koje čovjek može čuti nalaze se u intervalu od 20 Hz do 20 tisuća Hz. Zvuk
frekvencije iznad ljudskog čujnog područja naziva se ultrazvuk, a ispod infrazvuk. Neke
životinje koriste ultrazvuk za snalaženje u prostoru ili komunikaciju. Čovjek je također našao
načine kako primijeniti ultrazvuk.
U ovom radu opisane su vrste valova, kako ljudsko uho reagira na zvuk, zatim nastanak
i primjene ultrazvuka te primjer ultrazvučnog uređaja kućne izrade.Sound is a longitudinal wave which animals and humans notice with sense of hearing.
Frequencies of sound vibration that human ear can hear are located in interval from 20 Hz to
20 000 Hz. Sound of frequencies above human hearing range is called ultrasound and below
infrasound. Some animals use ultrasound to move around or to communicate. People have
also found ways to use ultrasound.
Various kinds of waves are described in this paper as well as how human ear reacts to
sound, also how ultrasound was made and applied and example of a home made ultrasound
device
Microwaves and their applications
Get PDFTema ovog završnog rada je Mikrovalovi i njihove primjene. Na početku rada opisani su
elektromagnetski valovi kako nastaju, kako se šire prostorom te neka njihova osnovna svojstva. U
sklopu elektromagnetskih valova opisan je i cijeli spektar elektromagnetskog zračenja i neka
osnovna svojstava svakog dijela spektra. U drugome dijelu rada opisani su mikrovalovi i primjene
mikrovalova u bežičnim komunikacijama, radaru i mikrovalnom zagrijavanju.The theme of this final paper is Microwaves and their application. At the beginning of the paper
described are the generation of electromagnetic waves, their expansion through the space and some
of their basic properties. As part of the electromagnetic waves the whole spectrum of
electromagnetic radiation is described as well as some basic properties of each part of the
spectrum. In the second part of the paper are described the microwave and microwave applications
in wireless communications, radar and microwave heating
Calculus of Variations
Get PDFU ovome radu ukratko ćemo se upoznati sa osnovama varijacijskih metoda. Bavit ćemo
se problemom traženja lokalnog minimuma određenog funkcionala, na način da tražimo nužne i
dovoljne uvjete postojanja ekstrema tog funkcionala. Upoznat ćemo se sa Euler - Lagrangeovom
jednadžbom, Hamiltonovim načelom, Sturm-Liouvilleovim operatorom i Rayleigh-Ritzovom
metodom. Također, razmatrat ćemo više metoda pronalaženja svojstvenih vrijednosti. Na
poslijetku ćemo pokazati kako se varijacijski postupak može proširiti za slučaj više nezavisnih
varijabli.In this paper, we will shortly be introduced to the basics of Calculus of Variations. We
will deal with problem of finding a local minima of certain functional in a way to seek the
necessary and sufficient conditions for the existence of ekstreme of this functional. We will meet
with Euler-Lagrange equation, Hamilton's principe, Sturm-Liouvilles operator and Rayleigh-Ritz
method. Also, we will consider more methods for finding eigenvalues. In the end, we will show
how calculus of variations can be extended to handle more than one independent variable
Methods of Entropy Coding
Get PDFKodiranje predstavlja transformaciju neke poruke ili općenito nekog objekta na način da se
simboli (slova, brojevi, pikseli, ...) tog objekta zamjene simbolima neke druge abecede (npr.
slova se zamjene brojevima). Metode entropijskog kodiranja vrše kodiranje bez gubitka, a
temelje se izravno na teoriji informacije. Osim toga, neke od metoda postižu vrlo efikasan omjer
kompresije što ih uz svojstvo kodiranja bez gubitka čini idealnim metodama kada se mora
sačuvati originalan oblik sadržaja. U ovom radu izloženo je pet metoda entropijskog kodiranja:
Shannon-Fanovo kodiranje, Huffmanovo kodiranje, aritmetičko kodiranje, metode rječnika i
metode skraćivanja niza.Coding represents the transformation of some message or generally an object in the way that
symbols (letters, numbers, pixels, ....) of that object being replaced with symbols of some other
alphabet (for example, letters being replaced with numbers). Methods of entropy coding perform
coding without loss, i.e. lossless compression. They are based directly on information theory. In
addition, some of the methods achieve very efficient compression ratio which makes them ideal
for coding when it is important to keep the original form of the content. In this thesis, five
methods of entropy coding are presented: Shannon-Fano coding algorithm, Huffman coding
algorithm, arithmetic coding algorithm, dictionary methods, and simple repetition suppression
Radiological characterization of the soil of Kopački rit
Get PDFZracenje iz tla ovisi o udjelu radioaktivih izotopa u tlu, a uglavnom potječe od primordijalnih
nuklida uranijeva i torijeva niza (238U,
232T h) i izotopa 40K. Analizom uzoraka dobivaju se informacije o prirodnoj radioaktivnosti te učincima ljudskih aktivnosti, pri -čemu je visokorezolucijska gamaspektrometrija jedna od osnovnih metoda za jednoznačnu identifikaciju gama emitera. U
radu su prikazani rezultati mjerenja koncentracije aktivnosti spomenutom metodom, a istraživanje
je provedeno za šest različitih lokacija Kopačkog rita. U tlu radionuklida pronađeni su izotopi koji
se često javljaju u prirodi, od kojih je očekivano najzastupljeniji
40K. Od antropogenih radionuklida
zabiljezeni su izotopi cezija ( 134Cs i
137Cs) čija je prisutnost prvenstveno posljedica nesreće
u černobilu i Fukushimi. 137Cs kao vanjski i unutarnji izvor zračenja od posebne je važnosti jer
može predstavljati opasnost za čovjeka s obzirom na dugo vrijeme poluraspada. Najveća koncentracija 137Cs određena je na lokaciji Dunav - Kazuk i ona iznosi 22,8 Bq/kg, dok su ostale vrijednosti znatno manje.The radiation from the soil depends on the ratio of radioactive isotopes in the soil, and mainly
comes from the primordial isotopes of uranium and thorium series (238U,
232T h) and 40K. With
sample analysis one obtains information about natural radioactivity and the effects of human activities,
where the high-resolution gamma spectrometry is one of the basic methods for unique
identification of gamma emitters. The work described in this report represents the investigation
with the same method undertaken with the intention of examining activity concetrations for six
different locations in Kopacki rit. Radionuclides that are generally highly abundant in the nature
were detected. Along with the isotopes of uranium series the most commmon nuclide is 40K.
Cesium isotopes have also been detected (134Cs and 137Cs) as a result of human activity (mainly
from Chernobyl and Fukushima accident). 137Cs as external and internal source of radiation is
important topic because it is highly toxic due to its long half-life of radioactive decay. The highest
concentration of 137Cs is detected at Dunav - Kazuk location (22,8 Bq/kg) while the values at
other locations are considerably smaller
E- Dnevnik
Get PDFU ovom diplomskom radu opisana je aplikacija e-Dnevnik koja se unazad nekoliko godina uvodi u hrvatsko školstvo putem pilot projekta e-Škole. U radu je dan naputak za korištenje aplikacije od strane nastavnika, roditelja i učenika. Također su navedene prednosti i nedostaci te planovi za daljnji razvoj e-Dnevnika u školstvu.This thesis describes the e-Dnevnik application which has been implemented into Croatian educational system for the past several years, as part of e-Schools pilot project. Thesis gives instructions for the use of application by teachers, parents and students. Also, some advantages and disadvantages are listed, as well as the plans for further development of e-Dnevnik in educational system
Transit of Mercury
Get PDFGlavni cilj ovog završnog rada bio je popratiti tranzit Merkura koji se dogodio 9.
svibnja 2016. godine, uočiti sve važne položaje, odnosno kontakte, Merkura na Sunčevom
disku te pripadajuća vremena zabilježiti u obliku teksta i fotografije. Prilikom izvođenja
promatranja, korišteni su osnovni instrumenti u astronomiji: teleskop, okulari i filteri.
Promatranje je održano u dvorištu Odjela za fiziku, Sveučilišta Josipa Jurja Strossmayera u
Osijeku, a njemu su mogli prisustvovati svi zainteresirani studenti.
Rad je koncipiran u dvije glavne cjeline. U prvom će dijelu biti opisane osnovne
karakteristike Merkura. Objasniti će se iznimna važnost pojave tranzita Merkura prilikom
njegova proučavanja. U dugom dijelu rada, biti će opisan postupak izvođenja promatranja i
navedena vremena s pripadajućim fotografijama kontaktnih točaka na Sunčevom disku.The main goal of this final thesis is to observe transit of Mercury that occurred on 9
May 2016, noted all important positions, or contacts, of Mercury on the solar disk and the
associated time record in the form of text and photos. During the observation, basic
instrumnets in astronomy, such as telescope, eyepieces and filters, were used. The observation
was held in the yard of Department of Physics, University of Josip Juraj Strossmayer and it
was open to attend to all interested students.
The work is divided into two main parts. In the first part, the features of Mercury and
the importance of Mercury transit for researching this planet will be explained. In the second
part, a method of performing observation will be described and the time with corresponding
photographs of contact points on the solar disk will be indicated