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U ovom je radu na temelju literature i znanja iz opće, moderne i kvantne fizike te znanstvenih radova i članaka, opisan način rada, dijelovi i vrste lasera te konačno karakteristike i primjena laserskog zračenja, s posebnim naglaskom na primjenu u medicini. Laser je izvor visokokoherentne monokromatske usmjerene svjetlosti velikoga intenziteta. Ubrzo nakon njegovog izuma, laser je zbog specifičnih svojstava pronašao primjenu u raznim područjima života. Najraznovrsniju primjenu lasersko zračenje ima u području medicine. Primjerice s laserom se može susresti prilikom provođenja znanstvenih istraživanja, u dijagnostici, terapiji i kirurgiji. Zbog iznimne snage koju lasersko zračenje može imati, prilikom rukovanja njime potrebno je koristiti zaštitnu opremu. This thesis is based on literature and knowledge from general, modern and quantum physics as well as scientific works and papers. The method of operation, parts, types of lasers and finally the characteristics and medical applications of laser radiation are described through thesis. A laser is a source of highly coherent monochromatic directional light of high intensity. Shortly after the invention of the laser, due to its specific properties, it found application in various areas of life. The most diverse application of laser radiation is found in the field of medicine. For example, lasers can be used in conducting scientific research, diagnostics, therapy, surgery, etc. Due to the extreme danger that laser radiation can have it is necessary to use appropriate protective equipment when handling it.

Kretanje utječe na biologiju ljudskog tijela. Oporavak je ključan za performanse tijekom treninga ili natjecanja, kao i na to kako se prilagođavamo nakon navedenog. Korištenje adekvatnih strategija vezano uz oporavak i uzimanje hranjivih tvari te količine energije prije, tijekom i nakon treninga i natjecanja - tako da je koncentracija postojana u organzmu tijekom vremena oko aktivnosti - može uvelike poboljšati performanse i oporavak. Fiziološki čimbenici su oni koji su dio posjedovanja tijela, kao što je: genetski sklop, posobnost oporavka (uključujući imunitet), veličina i sastav tijela, energetski zahtjevi, biološki spol i dob, razvojna faza i fizička zrelost. Čimbenici sporta i aktivnosti su oni koji su dio kretanja, kao što su: vrsta sporta ili aktivnosti i uključeni energetski sustavi, opterećenje i volumen treninga, ukupna kombinacija ili alostatsko opterećenje fizioloških stresora te fizičko okruženje u kojem se odvija kretanje. Trenažni proces jednostavno je poticaj za promjenu. Ovaj stimulans će dati rezultate samo ako je oporavak dostatan između dva treninga. Movement affects on the biology of the human body. Recovery is key for performance in trainings and competitions and how the body adjust to it. Using adequate strategies related to recovery and taking nutritious foods as well as amount of energy before, during and after the training and competitions - so the concentration is existent in your body in the times around the activity – can greatly improve performance and recovery. Physiological factors are the genetic set, recover ability ( including immunity), size and body composition, energetic demands, biological gender and age, growing phase and physical maturity. Factors of the sport and activity is the ones that are part of the movement, such as: type of sport or activity and energetic systems, load and volume of the training, total combination or allostatic load of physiological stressors and physical environment in which the movement is being done. Training process is incentive to change. This stimulans will give results only if there is a proper amount of recovery between the two trainings.

Številne države se zavezujejo k trajnostnemu razvoju in podnebni nevtralnosti, pri čemer so rešitve za energetske in okoljske izzive ključne za prehod v brezogljično gospodarstvo ter družbo. Energetska kriza in visoke cene energije so vplivale na pospešitev prehoda na čisto in trajnostno energijo. Izziv energetsko odvisne Evrope je v iskanju novih načinov pridobivanja energije iz obnovljivih virov energije in ob zavedanju, da obstoječa proizvodnja in poraba energije povzročata več kot 75 % emisij toplogrednih plinov v Evropski uniji. Med večje porabnike energije spada tudi gradbeništvo s stavbnim sektorjem, ki prispeva velik ogljični odtis. Pri uvajanju tehnologij obnovljivih virov energije nam je lahko v pomoč obnovljivi, zeleni nizkoogljični vodik zaradi svoje prilagodljivosti kot nosilec energije in medij za shranjevanje. Z njegovo uporabo lahko prispevamo k stroškovno učinkovitem razogljičenju Evropske unije in zmanjšanju njene odvisnosti od uvoza fosilnih goriv. Raba zelenega vodika pri ogrevanju stavb je v začetni fazi testiranja. S podporo zakonodaje in strategij na evropski in nacionalnih ravneh, tehnološkimi raziskavami in inovacijami, pametnim upravljanjem virov in pametno potrošnjo bomo lahko izboljšali industrijske ekosisteme, zmanjšali tveganja in prispevali k neto ničelnim emisijam. Namen prispevka je prikazati posamezne praktične primere uporabe zelenega vodika v stavbnem sektorju, pri čemer imajo pomembno vlogo zakonodaja, naložbe v infrastrukturo in proizvodnjo, varnost ter potrebe na trgu. Many countries are committed to sustainable development and climate neutrality, whereby solutions to energy and environmental challenges are key components for the transition to carbon-free economy and society. The energy crisis and the resulting high energy prices have had an impact on the acceleration of the transition to clean and sustainable energy. The challenge of Europe’s energy-dependence lies within the search for new ways of obtaining energy from renewable energy sources and the awareness that the existing energy production and consumption cause more than 75% of greenhouse gas emissions in the European Union. Major energy consumers, such as the construction sector with buildings. contribute to a large part of the carbon footprint. Renewa- ble, green, low-carbon hydrogen can help us in the deployment of renewable energy technologies due to its flexibility as an energy carrier and storage medium. By making use of it, we can contribute to the cost-effective decarbonisation of the European Union and reduce its dependence on fossil fuel imports. Green hydrogen as a source of building heating is in the initial phase of testing. By supporting legislation and strategies at the European and national levels, technological research and innovation, smart resour- ce management and smart resource consumption, we will be able to improve industrial ecosystems, reduce risks, and contribute to net zero emissions. The purpose of this article is to show individual practical cases of using green hydrogen in the building sector, where legislation, investments in infrastructure and production, safety and market need to play an important role.

Energy-efficient retrofits (EERs) are probably the most cost-effective method to address energy poverty in the residential sector. However, actual EER rates are far below those called for in recent policy goals. A large body of literature has examined the determinants influencing households’ EER decisions but with scattered and contextually limited results. Consequently, there is a lack of a comprehensive quantitative analysis of the literature in this area. In this study, a detailed literature review and bibliometric analysis of the determinants of EERs was conducted to better understand the scope and evolution of knowledge in this area. Specifically, 1198 scientific documents were systematically examined, with 1000 terms included in the final analysis. In addition, a new approach to bibliometric analysis was adopted, examining the content of abstracts rather than keywords, allowing for a more detailed analysis. This work contains important contributions. First, the result of this research is a detailed overview of the determinants of EER in residential buildings, which can be divided into five main groups: information and policy measures, economic factors, socioeconomic characteristics of households, technical and building characteristics and behavioural factors. Second, I conducted a bibliometric analysis that visualises the current state of knowledge regarding the determinants of EER in the literature. The results show that several groups of these determinants have been identified in the literature, the most influential of which are thermal comfort, energy cost, sustainable retrofit and behaviour change. These groups include 83 factors that are most relevant in the literature. Third, this study provides the historical evolution of the most influential EER determinants over the past three decades. The study suggests that future energy policies should use a mix of approaches to promote EER to comprehensively address the identified groups of determinants and multiple aspects of household members’ decision-making process.

Učenje kroz igru tehnika je koja uz pažljivo osmišljavanje može potaknuti aktivno učenje temeljeno na kritičkom promišljanju uz suradnju učenika. Uz dobro osmišljenu igru usvajanje nastavnih sadržaja je učinkovitije jer pobuđuje interes učenika. Učenici uglavnom samostalno oblikuju primjere hranidbenih lanaca, ali se mogu uočiti poteškoće u razumijevanju prijenosa energije kroz hranidbeni lanac. Igra “Zvjezdica za zvjezdicom” razvijena je u sklopu projekta (IP-CORONA-2020-12-3798), kojeg sufinancira Hrvatska zaklada za znanost. Cilj igre je osigurati razumijevanje hranidbenih odnosa kod učenika te njihovo povezivanje s prijenosom energije kroz hranidbeni lanac. Igra je provedena s 50 učenika 8. razreda. Raspravom s učenicima temeljem njihovih odgovora na radnim listićima, osmišljenim u svrhu vrednovanja za učenje, utvrđeno je da su učenici uglavnom uspješno ostvarili odgojno-obrazovne ishode koji provjeravaju razumijevanje hranidbenih odnosa i energijskih učinaka prehrane. Na temelju riješenosti zadataka na radnim listićima utvrđeno je da su uspješno usvojeni koncepti Međuovisnost živih bića, Održavanje ravnoteže u prirodi te Pretvorbe energije na razini ekosustava. Manje poteškoće su vidljive u razumijevanju koncepta Prijenos energije kroz hranidbeni lanac. Na temelju analize učeničkih odgovora, pretpostavlja se da bi boljem uspjehu pridonijela dublja rasprava temeljena na analizi učeničkih odgovora na pitanja po završetku igre., Learning through carefully designed game is a technique that can encourage active learning based on critical thinking with the participation of students. Well-designed game is more effective for adoption of teaching content because it arouses interest in students. Students generally independently form examples of food chains, but there can be difficulties in understanding energy transfer through food chain. The game "Star after star" was developed as part of the project (IP-CORONA-2020-12-3798) financed by the Croatian Science Foundation and was conducted with 50 8th graders. The aim of the game is ensuring that students understand nutritional relationships and their connection with energy transfer through food chain. By discussing with students based on their answers on worksheets, designed for the purpose of evaluation for learning, it was found that they mostly successfully achieved educational outcomes that test the understanding of nutritional relationships and energy effects of nutrition. Based on the completeness of the worksheets, it was found that the concepts of Interdependence of living beings, Maintaining natural balance and Energy conversion at the ecosystem level were successfully adopted. There were minor difficulties in understanding the concept of Energy transfer through food chain. After analysis of student responses, it is assumed that a deeper discussion based on the analysis of student responses at the end of the game would contribute to better success.

U ovom radu izračunata je toplinska bilanca za postrojenje koje proizvodi 900 MW električne energije i koristi paru tlaka 300 bar-a i temperature od 600 °C s jednim međupregrijanjem i 9 regenerativnih zagrijača napojne vode. U uvodnom dijelu rada opisane su termoelektrane sa naglaskom na nadkritična postrojenja i njihove parametre rada procesa. Izračunate su količine oduzimanja pare potrebne za regenerativno zagrijavanje napojne vode u četiri visokotlačna četiri niskotlačna i jednom otvorenom regenerativnom zagrijaču napojne vode. Tada je i određena ukupna količina potrebne pare koju generator pare mora proizvesti kao i potrebna količina prirodnog plina kao goriva kojeg koristi generator pare. Izračunata je iskoristivost takvog procesa u idealnim i realnim uvjetima. Izračunat je i sastav dimnih plinova te je predložen i sustav za odvajanje i uklanjanje ugljičnog dioksida. Proces je prikazan i u matematičkom modelu koristeći programski paket Ebsilon professional te je dana usporedba postrojenja podkritičnih i nadkritičnih parametara u tom modelu te je prikazano kako promjena parametara pare utječe na iskoristivosti i emisije postrojenja. Tu je jasno vidljiva prednost nadkritičnih postrojenja u smislu iskoristivosti i manjih emisija te je jasna težnja i pravac u kojem se razvijaju postrojenja takvih karakteristika. U drugom dijelu rada provedena je energijska i eksergijska analiza dijelova postrojenja i čitavog postrojenja te su prikazani energijski i eksergijski gubitci koji se pojavljuju na pojedinim dijelovima. Prikazano je kako promjena parametara okoline točnije temperature okoline utječe na eksergijsku analizu. To je jasan pokazatelj da takva vrsta analize može biti korištena za precizniju analizu postrojenja, njegovih gubitaka i iskoristivosti i poboljšanja koja je moguće provesti., In this work, the heat balance was calculated for a plant that produces 900 MW of electricity and uses steam of 300 bar pressure and temperature of 600 °C with one intermediate superheater and 9 regenerative feed water heaters. In the introductory part of the work, thermal power plants are described with an emphasis on supercritical plants and their parameters of process operation. Then, the amounts of steam extraction required for regenerative heating of feed water in four high-pressure, four low-pressure and one open regenerative feed water heater is calculated. After that, the total amount of required steam that the steam generator must produce is calculated as well as the required amount of natural gas as fuel used by the steam generator is determined. The efficiency of this process in ideal and realistic conditions was calculated. The composition of flue gases was also calculated and a system for separating and removing carbon dioxide was proposed. The process is also shown in a mathematical model using the Ebsilon professional software package, and a comparison of subcritical and supercritical plant parameters is provided with that model, and how the change in parameters affects plant utilization and emissions is shown. There is a clearly visible advantage of supercritical plants in terms of efficiency and lower emissions, and that makes clear the aspiration and the direction in design of technology advancements of such supercritical power plants. In the second part of the work, an energy and exergy analysis of parts of the plant and the entire plant was carried out, and the energy and exergy losses and efficiencies occurring in individual parts were presented. It is shown how the change of environmental parameters, more precisely the temperature of the environment, affects the exergetic analysis of losses and efficiencies. This is a clear indication that this type of analysis can be used for a more precise analysis of the plant, its losses, and efficiencies and for clearer view on the improvements that can be implemented.

U ovom radu prikazani su parametri napona kao pokazatelji kvalitete električne energije, koji se mjere i analiziraju posebnim uređajima. Mjerenja i analiza provedena je s uređajem PQube 3e proizvođača Powerside. Kvaliteta dovedene električne energije utječe na komfor kućanstava, dok kod industrija može uzrokovati financijske gubitke i kvarove. Utjecaj distribuiranih izvora ima sve veći utjecaj u kvaliteti isporučene električne energije. Mijenja se prikazivanje tokova energije od proizvođača do potrošača, dižu se naponske razine, jer u modernim mrežama potrošač može imati dualnu ulogu potrošača i proizvođača. Zbog promjene potrošnje tijekom dana u zgradi fakulteta, mijenja se i naponska razina. Fotonaponska elektrana ima velik utjecaj kod promjene naponske razine tako što diže naponsku razinu tijekom sunčanih sati u danu. This paper presents the voltage parameters as indicators of the quality of electricity, which are measured and analyzed with special devices. Measurements and analysis were carried out with the PQube 3e device manufactured by Powerside. The quality of supplied electricity affects the comfort of households, while it can cause financial losses and breakdowns in industries. The influence of distributed sources has an increasing impact on the quality of delivered electricity. The presentation of energy flows from producer to consumer is changing, voltage levels are rising, because in modern networks the consumer can have a dual role of consumer and producer. Due to the change in consumption during the day in the faculty building, the voltage level also changes. Photovoltaic power plant has a big impact on changing the voltage level by raising the voltage level during the sunny hours of the day.

Sva bića svakodnevno trebaju energiju za obavljanje osnovnih životnih procesa. Također, u zadnjih nekoliko desetljeća, moderna civilizacija je sve više ovisna o električnoj energiji za uspješno funkcioniranje. Energija koju koristimo dolazi iz primarnih izvora, a najbitniji takav izvor je Sunce. Za prikupljanje energije iz Sunca, još od kraja 19. stoljeća, koriste se solarne ćelije. Kako im i samo ime nalaže, prikupljanje energije iz Sunca moguće je samo tijekom vedrih i sunčanih dana. S obzirom na to da se neka područja u svijetu ne mogu osloniti na stalan pritok sunčevih zraka, znanstvenici traže nove načine sakupljanja sve one raspršene energije koja se, nažalost, ne iskorištava. Tako su, u zadnjih nekoliko godina, znanstvenici s različitih instituta napravili nekoliko uređaja koji sakupljaju energiju pomoću kišnih kapi. Tako je, svjetlo (vjerojatno kišnog) dana ugledao triboelektrični nanogenerator (TENG) kojim je, pomoću triboelektriciteta, moguće sakupljati energiju iz kišnih kapi. Zatim je, nekoliko godina kasnije, nastao generator energije na bazi kapljica (engl. droplet-based electricity generator, DEG) koji, uz nekoliko preinaka u strukturi TENG-a, postiže puno veću efikasnost. Upravo najzanimljiviji uređaj nastao je integriranjem triboelektričnog nanogeneratora na silikonsku solarnu ćeliju pomoću zajedničke elektrode načinjene od poli(3,4-etilendioksitiofena):poli(stirensulfonata), skraćeno PEDOT:PSS-a. Takav hibridni sustav prikupljanja energije kombinira prednosti visoke izlazne struje, koju daje solarna ćelija, s visokim izlaznim naponom TENG-a. Iz tih razloga, ovakav uređaj omogućuje sakupljanje energije neovisno o vremenskim prilikama i dobi dana. All beings need energy to carry out basic life processes every day. Also, in the last few decades, modern civilization is increasingly dependent on electricity for successful functioning. The energy we use comes from primary sources, and the most important of them is the Sun. Solar cells have been used to collect energy from the Sun since the end of the 19th century. As their name suggests, collecting energy from the Sun is only possible during clear and sunny days. Given that some areas in the world cannot rely on a constant influx of sunlight, scientists are looking for new ways to collect all that scattered energy that is, unfortunately, not used. So, in the last few years, scientists from different institutes have made several devices that collect energy using raindrops. Thus, the triboelectric nanogenerator (TENG) with which, using triboelectricity, is possible to collect energy from raindrops, saw the light of (probably rainy) day. Then, a few years later, a droplet-based electricity generator (DEG) was created, which, with several changes in the structure of the TENG, achieves much higher efficiency. The most interesting device was created by integrating a triboelectric nanogenerator on a silicon solar cell using a common electrode made of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate), abbreviated PEDOT:PSS. Such a hybrid energy harvesting system combines the advantages of the high output current of a solar cell with the high output voltage of a TENG. For these reasons, this kind of device enables the collection of energy regardless of the weather conditions and time of day.

Rad naziva Energija i oblik bavi se pojmom energije i pojedincem koji je subjektivno doživljava kroz crteže i grafike. Na početku rada razrađuju se tema i srodni pojmovi uz informacije iz odabrane literature. Potom je prikazan proces transformacije rada iz početnih stadija u završne, kao i misli i okruženja koja su ga pratila, ali i utjecala na sam proces. Naposljetku slijedi tehnička razrada rada, kao i objašnjenja postupaka. Rad pozitivno utječe na usmjerenje vlastitih misli i razvitak spoznaja o tome kako ljudska svijest može doprinijeti općenito. Poziva na promišljanje, ali i kreativno razmišljanje. The paper Energy and shape explores the term energy and the individual who is subjectively experiencing it through drawings and graphics. The beginning of the paper offers an insight into the topic and related terms along with the information from the selected literature. This is followed by the review of the transformation of the work from the beginning to its final form, as well as the thoughts and surroundings that followed along, but also affected the process itself. Lastly, there is a technical elaboration of the work along with some explanations of the procedures. The paper has a positive effect on the direction of one’s own thoughts and the development of knowledge about how human consciousness can contribute in general. It calls for contemplation, but also creative thinking.

U ovom završnom radu opisani su neki od najzastupljenijih suvremenih sustava i protokola za upravljanje rasvjetom. Sustavi i protokoli za upravljanje rasvjetom jedni su od važnijih faktora u svakodnevnom životu. Svaki moderni projekt sadrži neki od ovih sustava i protokola za upravljanje rasvjetom zbog potrebe za učinkovitom potrošnjom električne energije i zbog ekonomičnosti projekta. Završni rad sadrži prikaz povijesti rasvjete, različite mogućnosti regulacije rasvjete te projekt javne rasvjete. In this undergraduate thesis, some of the most common modern systems and protocols for lighting management are described. Systems and protocols for lighting management are one of the most important factors in everyday life. Every modern project contains some of these lighting management systems and protocols due to the need for efficient electricity consumption and economics. This undergraduate thesis contains a presentation of the history of lighting, different possibilities of lighting regulation and a public lighting project.