Repository of Karlovac University of Applied Sciences - Institutional Repository
Not a member yet
3017 research outputs found
Sort by
PECTIN AND EUGENOL AS ENVIRONMENTALLY ACCEPTABLE CORROSION INHIBITORS OF AIMg3 ALLOY IN ACIDIC MEDIUM
No full textAluminij i njegove legure su po industrijskoj važnosti odmah iza željeza, prvenstveno zbog svojih odličnih kemijsko-fizikalnih svojstava, no njihovim izlaganjem agresivnim sredinama, kao što je solna kiselina, a koja se koristi u procesima dekapiranja u industriji, dolazi do otapanja zaštitnog oksida odnosno otapanja aluminija. Kako bi se izbjegli gubici i zaštito metal kod korozije, danas se u otopinama najviše upotrebljavaju različiti inhibitori korozije koji moraju biti ekološki prihvatljivi. Stoga je u ovom radu ispitano potencijalno inhibicijsko djelovanje otopina pektina uz dodatak eugenola u otopini 10% solne kiseline na korzijsko ponašanje AlMg3 legure. Ispitivanja su potvrdila da 0,2% otopina pektina uz dodatak 800 ppm eugenola pokazuje vrlo dobra inhibicijska svojstva i to čak i pri povišenim temperaturama.Aluminum and its alloys are second only to iron in industrial importance, primarily due to their excellent chemical and physical properties, but their exposure to aggressive environments, such as hydrochloric acid, which is used in industrial pickling processes, leads to the dissolution of the protective oxide, or aluminum dissolution. In order to avoid losses and protect the metal during corrosion, various corrosion inhibitors are currently used in solutions, which must be environmentally friendly. Therefore, this paper examines the potential inhibitory effect of pectin solutions with the addition of eugenol in a 10% hydrochloric acid solution on the corrosion behavior of AlMg3 alloy. The tests confirmed that a 0.2% pectin solution with the addition of 800 ppm eugenol shows very good inhibitory properties, even at elevated temperatures
ANALYSIS OF THE EFFECT OF WORK STRESS ON WORK PRODUCTIVITY
No full textU ovom završnom radu istraživat će se psihosocijalni faktori poput stresa, motivacije i zadovoljstva te njihova povezanost i utjecaj na produktivnost rada. Kroz nekoliko teorijskih cjelina će se jednostavno objasniti svi pojmovi koji su važni za razumijevanje radnog stresa i produktivnosti na radu. Drugi dio završnog rada, analitičko-eksperimentalni dio, zasniva se na korištenju upitnika koji su ispunili zaposlenici Komunalnog poduzeća. U samom upitniku kroz 17 pitanja ispitivani su razni čimbenici koji se odnose na organizaciju i intenzitet rada, međuljudske odnose, odnose s nadređenima, klimu i atmosferu na radnom mjestu te uvjete rada. Cilj eksperimentalnog dijela je dobiti uvid jesu li radnici pod stresom, koji čimbenici utječu na pojavnost stresa i posljedično na produktivnost na radnom mjestu.In this final paper, psychosocial factors, such as stress, motivation and satisfaction, and their connection and impact on work productivity will be explored. Through several theoretical units, all terms that are important for understanding work stress and productivity at work will be explained simply. The second part of the final paper, the analytical experimental part, is based on the use of questionnaires filled out by the employees of the utility company. In the questionnaire itself, through 17 questions, various factors related to the organization and intensity of work, interpersonal relations, relations with superiors, climate and atmosphere at the workplace and working conditions were examined. The aim of the experimental part is to gain an insight into whether workers are under stress, which factors affect the incidence of stress and consequently, productivity at the workplace
PHYSICAL PROPERTIES OF RADIATION AND SOME MEASUREMENT TECHNOLOGIES
No full textU završnom radu objasnit će se zračenje, vrste zračenja i učinci. Te međudjelovanja između zračenja i tvari, međudjelovanje elektromagnetskoga zračenja i tvari koje se događa se na više načina također objašnjena u ovom radu. Opisati će se načini mjerenja ionizirajućeg zračenja te postupci, mjere prilikom zaštite od ionizirajućeg zračenja i uređaji za mjerenje i opažanje zračenja. Zakonska regulativa i nadležna tijela za zaštitu od ionizirajućeg zračenja u Republici Hrvatskoj također su opisana u radu, te temeljni zakoni iz kojih su doneseni pravilnici koji detaljnije uređuju pojedina područja i postupke zaštite.The final paper will explain radiation, types of radiation, and their effects. The interactions between radiation and matter, as well as the interaction of electromagnetic radiation with matter, which occur in various ways, will also be explained in this paper. The methods for measuring ionizing radiation, procedures, and measures for protection against ionizing radiation, along with devices for measuring and detecting radiation, will be described. The legal regulations and competent authorities for protection against ionizing radiation in the Republic of Croatia are also described in the paper, along with the fundamental laws from which regulations were derived that more specifically regulate individual areas and protection procedures
ENVIRONMENTALLY ACCEPTABLE METHODS FOR REMOVING HEAVY METALS FROM THE ENVIRONMENT
No full textTeški metali predstavljaju ozbiljnu prijetnju okolišu i ljudskom zdravlju zbog svoje toksičnosti, postojanosti i sposobnosti akumulacije u hranidbenom lancu. Uklanjanje ovih onečišćujućih tvari iz tla, vode i sedimenata zahtijeva primjenu učinkovitih, ali i ekološki prihvatljivih metoda. Ovaj rad daje pregled suvremenih tehnologija fokusiranih na smanjenje negativnog utjecaja teških metala na okoliš, uz poseban naglasak na održivost i minimalni sekundarni utjecaj. Detaljno su obrađene bioremedijacija i fitoremedijacija kao prirodne metode koje koriste mikroorganizme i biljke za dekontaminaciju. Također su opisane i metode kao što su adsorpcija, ionska izmjena, membranski procesi i elektrokemijski postupci, koje omogućuju visoku učinkovitost uz smanjenu potrošnju kemikalija i smanjenje otpada. Pored toga, razmotreni su i fizikalno-kemijski pristupi poput flotacije otopljenim zrakom, kemijskog taloženja, koagulacije i flokulacije, kao i napredne metode poput ustakljivanja i obrade opasnog otpada u ciklonima. Cilj rada bio je istaknuti prednosti, ograničenja i potencijal primjene pojedinih metoda u realnim uvjetima te prikazati važnost primjene ekološki održivih rješenja za sanaciju okoliša. Sve navedene metode imaju svoje specifične prednosti, a izbor optimalne tehnike ovisi o vrsti onečišćenja, karakteristikama okoliša te ekonomskim i tehničkim čimbenicima.Heavy metals are among the most hazardous pollutants in the environment due to their toxicity, persistence, and tendency to bioaccumulate. Their presence in soil, water, and air poses a serious threat to ecosystems and human health. In response to increasing environmental concerns, numerous remediation methods have been developed, with a special emphasis on eco-friendly approaches that minimize additional environmental impact. This paper provides an overview of various environmentally acceptable methods for the removal of heavy metals, including bioremediation, phytoremediation, adsorption, ion exchange, membrane processes, electrochemical methods, flotation with dissolved air, and chemical precipitation. Each of these methods is analyzed in terms of its effectiveness, sustainability, economic feasibility, and potential application in different environmental conditions. The paper highlights the advantages and limitations of each method and underlines the importance of choosing the appropriate technology depending on the type of contamination and specific site conditions. The application of green remediation methods represents a key step toward preserving natural resources and ensuring a healthier future
SAFETY MEASURES IN PRIMARY AND SECONDARY SCHOOLS
No full textSigurnosne mjere u školama ključne su za zaštitu učenika, nastavnog osoblja i imovine. S obzirom na sve veće izazove u društvu, škole moraju poduzeti odgovarajuće korake kako bi stvorile sigurno okruženje za učenje i rad. To uključuje fizičke mjere poput video nadzora, zaključavanja objekata, kontroliranja pristupa i održavanja sigurnosti na školskom dvorištu. Osim toga, važno je uvesti edukaciju za učenike i nastavnike o prepoznavanju i sprječavanju nasilja, bilo da se radi o fizičkom ili psihičkom nasilju. Također, škole se moraju pripremiti na prirodne nepogode i hitne situacije, osiguravajući učinkovite planove evakuacije i zaštite. Sve ove mjere zajednički doprinose sigurnosti svih osoba u obrazovnim ustanovama, omogućujući nesmetano i sigurno odvijanje obrazovnog procesa.Safety measures in schools are crucial for the protection of students, teaching staff, and property. Given the increasing challenges in society, schools must take appropriate steps to create a safe environment for learning and work. This includes physical measures such as video surveillance, securing school premises, controlling access, and maintaining safety in schoolyards. In addition, it is important to implement education for students and teachers on recognizing and preventing violence, whether it is physical or psychological violence. Schools must also prepare for natural disasters and emergencies by ensuring effective evacuation and safety plans. All these measures collectively contribute to the safety of everyone in educational institutions, enabling the smooth and secure continuation of the educational process
THE INFLUENCE OF OLIVE LEAF EXTRACT AND PROTECTIVE CULTURE ON THE PROPERTIES AND SHELF LIFE OF CHEESE
No full textSvježi sir je lako kvarljiv proizvod zbog visokog udjela vlage, pa mu je rok trajanja ograničen. U industrijskoj proizvodnji često se koriste konzervansi poput natamicina, dok se u tradicionalnoj proizvodnji oslanja na kuhinjsku sol i hlađenje. U novije vrijeme istražuju se alternativne metode produljenja trajnosti, poput primjene protektivnih kultura i biljnih ekstrakata. Protektivne kulture sadrže korisne bakterije koje sprječavaju razvoj patogenih mikroorganizama i čuvaju mikrobiološku stabilnost proizvoda. Ekstrakti biljaka, poput ekstrakta lista masline, sve se više istražuju zbog svojih antimikrobnih i antioksidativnih svojstava. Ovaj završni rad istražuje utjecaj protektivne kulture i ekstrakta lista masline na mikrobiološku stabilnost, fizikalno-kemijska i senzorska svojstva te sadržaj bioaktivnih komponenti svježeg sira, s ciljem utvrđivanja njihove učinkovitosti u produljenju roka trajanja i povećanju funkcionalne vrijednosti proizvoda.Fresh cheese is a highly perishable product due to its high moisture content, which limits its shelf life. While industrial production may use preservatives such as natamycin, traditional methods rely on table salt and refrigeration. Recently, alternative preservation methods have been explored, including the use of protective cultures and plant extracts. Protective cultures contain beneficial bacteria that inhibit the growth of pathogenic microorganisms and enhance microbiological stability. Plant extracts, such as olive leaf extract, are gaining attention for their antimicrobial and antioxidant properties. This thesis investigates the impact of protective cultures and olive leaf extract on the microbiological stability, physicochemical and sensory properties, as well as the bioactive compound content of fresh cheese. The main goal is to determine whether the addition of protective cultures and/or olive leaf extract can extend the shelf life and improve the functional value of fresh cheese
SAFETY OD FIREFIGHTERS DURING INTERVENTIONS
No full textSigurnost vatrogasaca tijekom intervencija predstavlja jedan od najvažnijih aspekata vatrogasne djelatnosti. Vatrogasci se svakodnevno suočavaju s brojnim opasnostima poput požara, eksplozija, urušavanja objekata, toksičnih plinova, električne energije i nepovoljnih vremenskih uvjeta. Zbog toga je ključno osigurati odgovarajuću zaštitnu opremu, kontinuiranu edukaciju i dobru pripremu za sve vrste intervencija. Organizacija i vođenje intervencije moraju biti jasno definirani, a zapovjedna struktura poštovana. Prije svakog izlaska na teren, potrebno je provesti procjenu rizika i osigurati da su svi članovi tima informirani o mogućim opasnostima i pravilima ponašanja. Posebna pažnja posvećuje se timskom radu, komunikaciji i stalnom praćenju situacije na terenu. Prevencija ozljeda i očuvanje zdravlja vatrogasaca također uključuje psihološku pripremu i podršku, jer su stres i emocionalni pritisak česti u ovom zanimanju. Primjena standardnih operativnih postupaka, redovita vježbanja i uporaba moderne tehnologije dodatno povećavaju razinu sigurnosti.The safety of firefighters during interventions is one of the most important aspects of firefighting activities. Firefighters face numerous dangers daily, such as fires, explosions, building collapses, toxic gases, electricityy and adverse weather conditions. Therefore, it is crucial to ensure the use of proper protective equipment, continuous training, and thorough preparation for all types of interventions. The organization and management of interventions must be clearly defined, and the command structure must be respected and adhered to. Before each deployment, a risk assessment should be conducted, and all team members must be informed of potential dangers and behavior protocols. Special attention is given to teamwork, communication, and constant monitoring of the situation on the ground. Injury prevention and the preservation of firefighters' health also include psychological preparation and support, as stress and emotional pressure are common in this profession. The application of standard operating procedures, regular drills, and the use of modern technology further increase the level of safety. Keywords: firefighter safety, firefighting interventions, personal protective equipment, risk assessment, operational tacticsrisk assessment should be conducted, and all team members must be informed of potential dangers and behavior protocols. Special attention is given to teamwork, communication, and constant monitoring of the situation on the ground. Injury prevention and the preservation of firefighters' health also include psychological preparation and support, as stress and emotional pressure are common in this profession. The application of standard operating procedures, regular drills, and the use of modern technology further increase the level of safety
ANALYSIS OF OCCUPATIONAL INJURIES IN THE REPUBLIC OF CROATIA FROM 2014 TO 2023
No full textOzljede su oštećenja koja na tijelu nastaju zbog djelovanja vanjske sile, stranih tvari, zračenja ili bioloških uzroka. Mogu uzrokovati lake ili beznačajne poremećaje, teška oštećenja organa i smrt, a praćene su i s mentalnim - akutnim i/ili kroničnim – promjenama različitog intenziteta. Poseban problem u svakom društvu su ozljede na radu jer su osim pratećih tjelesnih i duševnih oštećenja i patnji praćene troškovima zajednice i poslodavca, osobnim i obiteljskim troškovima zbog liječenja, socijalnim i drugim problemima. Cilj ovog rada je analiza težina i vrsta ozljeda na radu u Republici Hrvatskoj od 2014. do 2023. godine. Učinjena je retrospektivna analiza prospektivne baze podataka Hrvatskog zavoda za zdravstveno osiguranje (HZZO) u razdoblju od 2014. do 2023. god. Bazu podataka HZZO čine prijave ozljeda na radu koje su dostavljene HZZO-u zbog ostvarivanja prava koja su utvrđena Zakonom o obveznom zdravstvenom osiguranju. Analizirane su sve prijavljene ozljeda na radu bez obzira da li ih je povjerenstvo HZZO-a priznalo ili nije priznalo. Ozljede na radu su definirane prema našem Zakonu o obveznom zdravstvenom osiguranju. Analizirani su slijedeći podaci u razdoblju od 2014. do 2023. godine (sukladno ESAW metodologiji): broj prijavljenih ozljeda na radu, broj prijavljenih ozljeda na radu prema dobnim skupinama radnika, broj prijavljenih ozljeda prema težini ozljeda, broj prijavljenih ozljeda na mjestu rada, broj prijavljenih ozljede prema ozlijeđenom dijelu tijela, broj prijavljenih ozljeda na mjestu rada prema vrsti ozljede. Ukupan broj ozljeda na radu rastao je u periodu od 2014. do 2018. godine. Broj se je počeo smanjivati 2019. i 2020. godine, a onda u periodu od 2021. do 2023. ponovo raste. Najveći ukupan broj prijavljenih ozljeda zabilježen je 2018. (18724), a najmanji 2014. godine (13929). U navedenom razdoblju zabilježeno su 119.434 ozljede na radu: lakih 87,49%, teških 11,45%, skupnih 0,14% i sa smrtnim ishodom 0,21%. Najveći broj se je desio na mjestu rada (115.859), znatno manje na povremenom ili pokretno mjesto rada ili putovanje po nalogu poslodavca (16.002). Najčešće su bile ozljede (ukupan broj od 2014. do 2023.) gornjih okrajina (52.169), donjih (41.681), glave (13.435), vrata, leđa i kralježnice (8.748), ozljede cijelog tijela višestruko (7.321), trupa i organa (4.693). Najveći broj ozljeda su rane i površinske ozljede (48.863), iščašenja, uganuća i nategnuća (34.723), prijelomi kostiju (20.269), stanje šoka (3.607), potres mozga i unutarnje ozljede (3.308) i višestruke ozljede (3.252). Uspoređivanjem podataka s drugim zemljama (primarno EU) zapažamo sličnosti nekih podataka, ali i razlike. Drugim istraživanjima bilo bi potrebno utvrditi uzroke koji su uvjetovali razlike u broju ozlijeđenih nizom čimbenika (vrsta djelatnosti, zaštita na radu, edukacija, ekonomsko i socijalno stanje, bilježenje podataka o ozlijeđenim osobama, uloga pravosudnog sustava i drugo). Pandemija bolesti COVID-19 imala je značajan utjecaj na gospodarstvo svih zemalja, a time i ozljede na radu.Injuries are damage to the body caused by external forces, foreign substances, radiation or biological causes. They can cause mild or insignificant disorders, severe organ damage and death, and are accompanied by mental changes of varying intensity, which may be acute and/or chronic. Occupational injuries are a special problem in every society because, in addition to accompanying physical and mental damage and suffering, they also generate costs for the community and the employer, as well as personal and family costs due to treatment and social or other problems. The aim of this thesis is to analyze the severity and types of occupational injuries in the Republic of Croatia from 2014 to 2023. A retrospective analysis of the prospective database of the Croatian Health Insurance Fund (HZZO) was conducted in the period from 2014 to 2023. The HZZO database consists of reports of occupational injuries submitted to the HZZO in order to exercise the rights established by the Mandatory Health Insurance Act. All reported occupational injuries were analyzed, regardless of whether the HZZO committee had recognized them or not. Occupational injuries are defined according to the Croatian Mandatory Health Insurance Act. The following data was analyzed in the period from 2014 to 2023 (in accordance with the ESAW methodology): number of reported occupational injuries, number of reported occupational injuries by age group of workers, number of reported occupational injuries by severity of injuries, number of reported injuries in the workplace, number of reported occupational injuries by injured body parts, number of reported occupational injuries by type of injury. The total number of occupational injuries grew in the period from 2014 to 2018. The number began to decrease in 2019 and 2020, and then in the period from 2021 to 2023, it increases again. The highest total number of reported injuries was recorded in 2018 (18,724), and the lowest in 2014 (13,929). In the aforementioned period, 119,434 occupational injuries were recorded: 87.49% minor, 11.45% serious, 0.14% collective and 0.21% fatal. The highest number of injuries occurred in the workplace (115,859), significantly fewer at a temporary or mobile workplace, or during travel at the employer's request (16,002). The most common injuries (total number from 2014 to 2023) were injuries to the upper extremities (52,169), lower extremities (41,681), head (13,435), neck, back and spine (8,748), multiple injuries to the whole body (7,321), trunk and organs (4,693). The largest number of injuries are wounds and superficial injuries (48,863), dislocations, sprains and strains (34,723), bone fractures (20,269), shock (3,607), concussion and internal injuries (3,308) and multiple injuries (3,252). Comparing data with other countries (primarily the EU), we note similarities in some data, as well as differences. Further research would be necessary to determine the causes underlying the differences in the number of injured by a variety of factors (type of activity, occupational safety, education, economic and social situation, recording data on injured persons, the role of the judicial system, etc.). The COVID-19 pandemic had a significant impact on the economy of all countries, and thus on occupational work as well
MANAGEMENT FUNCTIONS IN THE ORGANISATION ODAŠILJAČI I VEZE D.O.O.
No full textMenadžment je proces oblikovanja i održavanja okruženja kako bi se postavljeni ciljevi mogli efikasno ostvariti. Menadžment je proces postizanja željenih rezultata kroz efikasno korištenje ljudskih i materijalnih resursa, odnosno sustavan način usmjeravanja pojedinaca, skupina poslova i operacija s ciljem ostvarivanja postavljenih organizacijskih ciljeva sa sredstvima koje organizaciji stoje na raspolaganju. Ovaj završni rad je podijeljen na dvije cijeline te će u prvom dijelu biti opisane funkcije menadžmenta u teoriji dok će u drugom dijelu funkcije menadžmenta biti prikazane na primjeru organizacije „Odašiljači i veze“ d.o.o.Management is the process of shaping and maintaining the environment so that the set goals can be effectively achieved. Management is the process of achieving the desired results through the efficient use of human and material resources, that is, a systematic way of directing individuals, work groups and operations with the aim of achieving set organizational goals with the means available to the organization. This final thesis is divided into two wholes, and in the first part, management functions will be described in theory, while in the second part, management functions will be shown on the example of the organization "Odašiljači i veze" d.o.o
TESTING OF THE HARDNESS OF FLEXIBLE MATERIALS
No full textU ovom istraživanju ispitivane su tvrdoće fleksibilnih materijala izrađenih aditivnom proizvodnjom. Detaljno su opisane metode ispitivanja materijala, s posebnim naglaskom na metodu ispitivanja tvrdoće Shore A, koja je prilagođena ispitivanju fleksibilnih materijala. Također su analizirane osnovne razlike između polimernih materijala, uz osvrt na njihovo ponašanje pri povišenim temperaturama. Eksperimentalni dio uključuje opis korištene opreme, ispitivanih materijala te metode aditivne proizvodnje korištene za izradu testnih epruveta. Prikazani su rezultati ispitivanja tvrdoće, koji su analizirani pomoću aritmetičke sredine i standardne devijacije. Na temelju rezultata doneseni su relevantni zaključci.This research is based on testing of the hardness of flexible materials. The material testing methods are described in detail, with special emphasis on the Shore A hardness test method, which is adapted to the testing of flexible materials. The basic differences between polymeric materials are also analyzed, with a focus on their behavior at elevated temperatures. The experimental part includes a description of the equipment used, the materials tested, and the additive manufacturing method used to produce the test specimens. The hardness test results are presented, which are analyzed using the arithmetic mean and standard deviation. Relevant conclusions are drawn based on the results