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Application of Kaizen and Lean approaches in pharmaceutical industry
No full textU krajoliku modernih radnih mjesta koji se brzo razvija, zdravlje i sigurnost radnika postali su najvažniji problemi za organizacije u različitim sektorima. U ovom radu prikazani su primjeri implementacije Kaizena i Lean pristupa, jer poduzeća teže poboljšanju operativne učinkovitosti i njegovanju kulture sigurnosti. Metodologije kao što su Kaizen i Lean, koje potječu iz japanske proizvodne industrije, stekle su važnost. Oba pristupa naglašavaju stalno poboljšanje i smanjenje otpada, ali također imaju značajan potencijal za poboljšanje zdravlja i sigurnosti radnika. Cilj ovog rada bio je otkriti koliko su ljudi upoznati s metodologijama Kaizena i Leana te kako primjena tih metodologija može poboljšati uvjete rada i sigurnosne protokole. Oba pristupa dijele bitna načela, kao što su poštovanje prema ljudima, predanost kvaliteti i neumoljiva potraga za učinkovitošću, koja postavljaju temelje za poboljšanje zdravlja i sigurnosti radnika u organizacijama. Uz to, istraživalo se koliko su dugo radnici na svojim radnim mjestima, te koliko su zadovoljni općim uvjetima i sigurnošću na radnom mjestu. Primjena Kaizena i Leana u zdravlju i sigurnosti radnika sve su očitije te organizacije provode strategije kontinuiranog poboljšanja kako bi unaprijedile sigurnosne protokole. Kaizen potiče uspostavljanje sigurnosnih krugova, gdje zaposlenici na svim razinama sudjeluju u prepoznavanju sigurnosnih problema, predlaganju poboljšanja i razmjeni najboljih praksi. Ovaj suradnički pristup ne samo da osnažuje radnike, već i potiče osjećaj vlasništva nad njihovom sigurnošću i dobrobiti. Iz istraživanja se uvidjelo da proizvodnja ima pozitivan pomak uvođenjem novih tehnologija i Lean alata, većina zaposlenika ima pozitivan stav prema svom poslodavcu, što je dobar znak za organizaciju. Međutim, postojanje zaposlenika s neutralnim ili nezadovoljnim stavom ukazuje na to da ima prostora za poboljšanje kako bi se povećalo opće zadovoljstvo zaposlenika.In the rapidly evolving landscape of modern workplaces, employee health and safety have become paramount concerns for organizations across various sectors. This paper presents examples of the implementation of Kaizen and Lean approach, as companies strive to improve operational efficiency and foster a culture of safety. Methodologies such as Kaizen and Lean, which originate from the Japanese manufacturing industry, have gained importance. Both approaches emphasize continuous improvement and waste reduction, but they also hold significant potential for enhancing worker health and safety. The aim of this paper was to explore how familiar people are with the Kaizen and Lean methodologies and how the application of these methodologies can improve working conditions and safety protocols. Both approaches share essential principles, such as respect for people, commitment to quality, and an unrelenting pursuit of efficiency, which lay the foundation for improving worker health and safety in organizations. Additionally, the study examined how long employees have been in their workplaces and how satisfied they are with general working conditions and safety in the workplace. The application of Kaizen and Lean to worker health and safety is becoming increasingly evident as organizations implement continuous improvement strategies to enhance safety protocols. Kaizen encourages the establishment of safety circles, where employees at all levels participate in identifying safety issues, proposing improvements, and sharing best practices. This collaborative approach not only empowers workers but also fosters a sense of ownership over their safety and well-being. The research revealed that the introduction of new technologies and Lean tools in production has led to positive changes, with most employees having a positive attitude toward their employer, which is a good sign for the organization. However, the existence of employees with neutral or dissatisfied attitudes indicates that there is room for improvement to increase overall employee satisfaction
Hazard identification and risk assessment of electricians in work with car baskets in the trade E.M.G.
No full textOvaj rad fokusira se na procjenu rizika elektroinstalatera pri radu s autokošarom u okviru obrta E.M.G. Cilj istraživanja je identificirati potencijalne opasnosti koje se javljaju tijekom korištenja autokošare u elektroinstalaterskim poslovima te predložiti odgovarajuće sigurnosne mjere za sprječavanje nastanka ozljede na radu. Na početku se daje uvod u važnost procjene
rizika i oslanja se na Pravilnik o izradi procjene rizika, koji detaljno opisuje postupak i prikupljanje potrebnih podataka. Posebna pažnja posvećena je opasnostima pri radu s autokošarom. Kroz analizu postojećih propisa, istražene su najčešće opasnosti poput rizika od električnog udara, pada s visine te ostale opasnosti koje mogu nastati tijekom rada. Nakon toga
slijedi procjena rizika specifična za obrt E.M.G., gdje se identificiraju opasnosti, štetnosti i napori vezani uz poslove elektroinstalatera. Posebna pažnja posvećena je opasnostima pri radu s autokošarom. Na temelju pregleda i analiza, donose se prijedlozi za poboljšanje sigurnosnih standarda i edukaciju elektroinstalatera o pravilnoj primjeni autokošare radi smanjenja rizika i osiguranja sigurnosti radnika. U radu se također utvrđuju mjere za uklanjanje ili smanjivanje tih opasnosti, kao i detaljne upute za siguran rad.This paper focuses on the risk assessment of an electrician working with a boom lift within the business E.M.G. The aim of the research is to identify potential hazards that arise during the use of a boom lift in electrical installation work and to propose appropriate safety measures to prevent workplace injuries. The introduction highlights the importance of risk assessment and refers to the Risk Assessment Regulations, which detail the procedure and collection of necessary data. Special attention is given to the hazards associated with working with a boom
lift. Through the analysis of existing regulations, the most common hazards such as the risk of electric shock, falls from heights, and other dangers that may arise during work are explored. This is followed by a risk assessment specific to the business E.M.G., identifying the hazards,
harmful factors, and efforts related to the tasks of an electrician. Special emphasis is placed on the dangers of working with a boom lift. Based on the review and analysis, proposals are made to improve safety standards and educate electricians on the proper use of the boom lift to reduce risks and ensure worker safety. The paper also establishes measures for eliminating or reducing these hazards, as well as detailed instructions for safe work
Assessment of working posture and noise exposure of the operator of the dynamic testing machine
No full textSigurnost rada operatera bilo kojeg uređaja od izrazite je važnosti. U ovom diplomskom radu ispitana je sigurnost rada operatera dinamičkog ispitnog uređaja (tip LFV-100-HH) smještenog u Centru za ljevarstvo – SIMET na Metalurškom fakultetu Sveučilišta u Zagrebu. U radu je provedena procjena držanja tijela operatera pri provođenju radnji promjene čeljusti za prihvat epruveta te postavljanje epruvete u čeljusti ispitnog uređaja. Procjena je provedena ergonomijskom REBA (Rapid Entire Body Assessment) metodom koja analizira utjecaj samog rada na tijelo radnika. Procjena je provedena klasično pomoću radnog lista, a provjerena je korištenjem programskog paketa ErgoFellow 3.0. Nakon ergonomijske procjene provedena su mjerenja buke kojoj je izložen operater pri provedbi različitih tipova eksperimenata. Prvo je izmjerena buka pri praznom hodu uređaja s isključenim i uključenim zračnim ventilatorom za hlađenje rashladne tekućine koja ohlađuje hidrauličko ulje potrebno za rad ispitnog uređaja. Zatim su provedena mjerenja buke s uključenim ventilatorom pri provedbi monotonog testa te pri provedbi cikličkih testova u kojima se varirala amplituda titranja sile i frekvencija titranja sile. U teorijskom dijelu rada dane su osnove provođenja procjene ergonomijskom REBA metodom, provođenja monotonih i cikličkih testova te ispitivanja buke. Kod izvođenja monotonog testa pri radu s ventilatorom uređaja za hlađenje i prilikom mjerenja buke u praznom hodu prilikom rada ventilatora i bez rada ventilatora dobivene vrijednosti su približne, ispod 75 dB. Ispitivanjima je ustanovljeno da je pri provedbi cikličkih testova prilikom povećanja amplitude titranja sile nastala povećana buka koja se približila donjoj upozoravajućoj vrijednosti buke koja iznosi 80 dB. Analizom provedenih ergonomijskih procjena radnih položaja operatera i izmjerenih vrijednosti buke predložile su se mjere prilagođavanja rada operateru s ciljem njegova olakšavanja i povećanja sigurnosti na radu.The safety of the operator of any device is extremely important. In this thesis, the safety of the operator of the dynamic testing machine (type LFV-100-HH) located in the Center for Foundry - SIMET at the Faculty of Metallurgy of the University of Zagreb was examined. In the thesis, the body posture of the operator was evaluated when performing the actions of changing the jaws for accepting the test tubes and placing the test tube in the jaws of the test device. The assessment was carried out using the ergonomic REBA (Rapid Entire Body Assessment) method, which analyzes the impact of the work itself on the worker's body. The assessment was carried out classically using a worksheet, and was checked using the ErgoFellow 3.0 software package. After the ergonomic assessment, noise measurements to which the operator is exposed during the implementation of various types of experiments were conducted. First, the noise was measured when the device was idling with the air fan turned off and on to cool the coolant that cools the hydraulic oil required for the operation of the test device. Noise measurements were then carried out with the fan switched on during the implementation of the monotonous test and during the implementation of cyclic tests in which the amplitude of the force oscillation and the frequency of the force oscillation varied. In the theoretical part of the paper, the basics of conducting an assessment using the ergonomic REBA method, conducting monotonous and cyclic tests and noise tests are given. When performing a monotonous test when working with a fan of the cooling device and when measuring the noise at idle when the fan is working and without the fan, the values obtained around 75 dB. The tests established that during the implementation of cyclic tests, when the force vibration amplitude was increased, increased noise was produced, which approached the lower warning noise value of 80 dB. Through the analysis of the ergonomic assessments of the operator's working posture and the measured noise values, measures were proposed to adjust the operator's work with the aim of making it easier and increasing safety at work
Characterization of titanium alloy with the addition of copper for biomedical applications
No full textKarakterizacija legure titana s dodatkom bakra za biomedicinske primjene uključuje sveobuhvatnu procjenu svojstava materijala i prikladnosti za upotrebu. Legure titana često se biraju zbog njihove biokompatibilnosti i mehaničkih svojstava, dok se bakar može dodati radi poboljšanja specifičnih karakteristika poput antibakterijskog djelovanja. Glavni cilj ovog rada je konvencionalnim postupcima metalurgije praha proizvesti leguru titana s dodatkom 8% bakra koja bi imala biomedicinsku primjenu, a učinak procesnih parametara, kao što su vrijeme miješanja i tlak prešanja, na mikrostrukturne karakteristike proizvedene legure procijeniti korištenjem odgovarajućih metoda. Rezultati provedenih istraživanja pokazuju da je korištenjem metalurgije praha moguće proizvesti kompaktnu titan-bakar leguru, uz dodatno podešavanje procesnih parametara. Poglavito se to odnosi na vrijeme miješanja elementarnih prahova.The characterization of a titanium alloy with added copper for biomedical applications requires a comprehensive evaluation of its material properties and suitability for use. Titanium alloys are often selected for their biocompatibility and mechanical properties, while copper can be added to enhance certain properties such as antibacterial activity. The main objective of this work is to apply conventional powder metallurgy techniques to produce a titanium alloy with 8% copper addition for biomedical applications. The effects of processing parameters such as mixing time and compaction pressure on the microstructural properties of the produced alloy are evaluated using appropriate methods. The results of the research carried out show that it is possible to produce a compact titanium-copper alloy using powder metallurgy, but that it is necessary to adjust processing parameters, especially the mixing time of the starting powders
Technological and constructional calculation of the recuperators for air preheating on the cupola furnace
No full textU slučajevima pripreme taline za proizvodnju odljevaka većih tonaža, najčešća metoda taljenja u ljevaonicama lijevanog željeza je kupolna peć. Glavne prednosti kupolnih peći u usporedbi s električnim su: manje su osjetljive na nekvalitetne sirovine i onečišćenja, reakcije oksidacije i redukcije odvijaju se unutar i iznad zone taline tijekom procesa taljenja, što omogućuje korištenje visoko oksidiranog i nekvalitetnog otpadnog materijala, niže cijene legura i nemetalnih dodataka. Metalurški proces u kupolnoj peći može se intenzivirati predgrijavanjem zraka koji se kroz mlaznice upuhuje u radni prostor peći. Osim povećanja produktivnosti agregata, postiže se i smanjena potrošnja koksa te više temperature taline. Za kupolnu peć kapaciteta 3 t/h izvršen je tehnološko-konstrukcijski proračun sekcija rekuperatora. Proračun se temelji na eksperimentalnim podacima peći i rekuperatora koji se koriste u praksi. Kako bi se
postigla temperatura struje vrućeg zraka do 600°C i iskoristila energija povezana s emisijom CO u otpadnim plinovima, usvojen je sustav oporabe otpadnog plina koji se sastoji od tri sekcije rekuperatora. U prvom, teoretskom dijelu, dat je opis kupolnih peći, opis i podjela rekuperatora i njihove konstrukcijske razlike, te opis prijenosa energije u rekuperatoru. U drugom dijelu diplomskog rada izvršen je tehnološko-konstrukcijski proračun sekcija rekuperatora.In cases of melt preparation for larger tonnage production, the most common melting used in cast iron foundries is the cupola furnace. The main advantages of cupola furnaces compared to electric ones are: less sensitive to low quality charge materials and contaminants,
oxidation and reduction reactions take place within and above the melt zone during cupola melting, which allows the use of highly oxidized and low quality scrap material, lower prices of alloys and non-metallic additions. The metallurgical process in the cupola furnace can be
intensified by preheating the air that is blown into the working space of the furnace through nozzles. In addition to increasing aggregate productivity, reduced coke consumption and higher
melt temperatures are also achieved. For the cupola furnace with a capacity of 3 t/h, the technological and constructional calculation of the recuperator sections was carried out. The calculation is based on the experimental data of furnaces and recuperators that are used in practice. In order to reach the temperature of the hot air blast up to 600°C and to use the energy associated with CO emission in the waste gases, the recovery waste gas system consisting of three recuperator sections was adopted. In the first, theoretical part, there is a description of
cupola furnaces, a description and division of recuperators and their structural differences, and adescription of energy transfer in the recuperator. In the second part of the thesis, the technological and construction calculation of the recuperator sections was carried out
The impact of stress factors on the health of workers in healthcare institutions
No full textStresni faktori u zdravstvenim ustanovama imaju značajan utjecaj na zdravlje radnika. Fizički, psihološki, organizacijski i socijalni stresori mogu izazvati probleme kao što su kardiovaskularne bolesti, anksioznost, depresija i sindrom sagorijevanja na poslu. Osim toga, stres negativno utječe na kvalitetu pružanja zdravstvene skrbi. Upravljanje stresom kroz samostalnu skrb, organizacijske intervencije i podršku tima ključno je za zaštitu zdravlja radnika i poboljšanje kvalitete skrbi. Kako bi se smanjio utjecaj stresnih faktora na zdravlje radnika, potrebno je provoditi strategije za upravljanje stresom. To uključuje promicanje samo skrbi i strategija suočavanja sa stresom, implementaciju organizacijskih intervencija poput fleksibilnog radnog vremena i podrške nadređenih, poticanje timskog pristupa i međusobne podrške te edukaciju o upravljanju stresom i mentalnom zdravlju. Cilj ovog rada je uvidjeti utjecaj stresnih faktora na zdravlje radnika u zdravstvenim ustanovama te intervencije za osiguranje dobrobiti zdravstvenih radnika i poboljšanje kvalitete pružanja zdravstvene skrbi. Daljnja istraživanja i primjena preventivnih mjera trebaju biti usmjereni na smanjenje stresa i stvaranje podražavajućeg radnog okruženja za zdravstvene radnike.The stress factors in health care facilities have a significant impact on the health of employees . Physical, psychological, organizational, and social stressors can lead to problems such as cardiovascular diseases, anxiety, depression, and burnout. In addition, stress has a negative impact on the quality of health care. Managing stress through self-care, organizational interventions, and team support is crucial for protecting the health of workers and improving the quality of care. To reduce the impact of stress factors on workers health, it is necessary to implement stress management strategies. This includes promoting self-care and coping strategies, implementing organizational interventions such as flexible working hours and supervisor support, promoting a team approach and mutual support, and providing education on stress management and mental health. In summary, understanding the impact of stress factors on the health of workers in healthcare institutions is crucial for ensuring their well-being and improving the quality of healthcare delivery. Further research and implementation of preventive measures should be focused on reducing stress and creating a conducive working environment for healthcare workers
Preparation of risk assessment and the role of protection and security engineers in it
No full textCilj ovog završnog rada jest objasniti važnost dobre procjene rizika, poštivanja postavljenih mjera i uvjeta, te ulogu inženjera zaštite i sigurnosti u cijelom procesu izrade procjene rizika. Procjena rizika ima najveći utjecaj na sigurnost i radne uvjete svakog radnog mjesta. Kako bi procjena rizika bila kvalitetna i adekvatna za određeno radno mjesto, u procjenu se moraju uključiti i sami radnici koji svojim iskustvom pomažu inženjeru zaštite i sigurnosti da što kvalitetnije predvidi štetnosti, opasnosti, rizike i napore tog radnog mjesta. U izradi veliku ulogu imaju i mjerni uređaji koji inženjeru daju točne podatke o vrijednostima i parametrima koji pomažu u postavljanju granica i određivanju određenih uvjeta. Na kraju svake procjene rizika inženjer mora predstaviti paket mjera koje će smanjiti rizik i povećati kvalitetu rada.The goal of this studywork is to explain the importance of a good risk assessment, compliance with the set measures and conditions, and the role of the protection and safety engineer in the entire process of creating a risk assessment. Risk assessment has the greatest impact on the safety and working conditions of each workplace. In order for the risk assessment to be of high quality and adequate for a certain workplace, the workers themselves must be included in the assessment, who, with their experience, help the protection and safety engineers to predict the harms, dangers, risks and efforts of that workplace as well as possible. Measuring devices also play a significant role in manufacturing, which provides the engineers with accurate data on values and parameters that help set limits and determine certain conditions. At the end of each risk assessment, the engineer must present a package of measures that will reduce risk and increase the quality of work
Application of copper and its alloys in metallurgy
No full textPrimjena bakra i njegovih legura u metalurgiji ima značajan utjecaj na različite industrije. Bakar, kao izuzetno provodljiv metal, koristi se u elektrotehnici za izradu električnih vodiča, transformatora i elektromotora. U građevinarstvu, bakar se primjenjuje zbog svoje otpornosti na koroziju u instalacijama za vodu. Medicinska industrija koristi bakar zbog njegovih antimikrobnih svojstava. Razne legure bakra, kao što su bronca, mjed i fosforna bronca pružaju različite karakteristike kao što su čvrstoća, termička stabilnost i otpornost na habanje. Te legure se koriste za izradu predmeta kao što su nakit, dijelovi satova, ventili, opruge i komponente u avioindustriji. Iako legure bakra omogućavaju raznovrsnu primjenu, važno je razmotriti i utjecaj na okoliš. Procesi proizvodnje bakra mogu imati negativan efekt na životnu sredinu kroz emisiju plinova i otpadnih voda. Međutim, inovacije u tehnologiji i pristupi održivom razvoju pomažu smanjiti negativne utjecaje.The use of copper and its alloys in metallurgy has a significant impact on various industries. Copper, as an extremely conductive metal, is used in electrical engineering to make electrical conductors, transformers and electric motors. In construction, copper is used for its resistance to corrosion in water installations. The medical industry uses copper for its antimicrobial properties. Various copper alloys such as bronze, brass and phosphor bronze provide different characteristics such as strength, thermal stability and wear resistance. These alloys are used for jewelry, watch parts, valves, springs and components in the aero industry. Although copper alloys enable a variety of applications, it is also important to consider the impact on the environment. Copper production processes can have a negative effect on the environment through the emission of gases and waste water. However, innovations in technology and approaches to sustainable development are helping to reduce those negative impacts
Environmental responsibility of design
No full textJedan od temeljnih ciljeva dizajna je stvaranje ekološki prihvatljivih proizvoda i procesa. Nažalost, mnogo puta u prošlosti implikacije na okoliš bile su zanemarene tijekom faze dizajna novih proizvoda i procesa. Cilj ovog završnog rada, koncipiranog kao pregledni je istražiti sva područja industrijskog dizajna sa stajališta održivosti.One of the fundamental goals of design is to create environmentally friendly products and processes. Unfortunately, many times in the past the environmental implications were neglected during the design phase of new products and processes. The aim of this final paper, conceived as an overview, is to explore all areas of industrial design from the point of view of sustainability
Hazards at the production of titanium alloys in the electric arc furnace
No full textThis article describes the metal titanium, its characteristics and properties, and the types of titanium alloys with regard to its microstructure. It also describes the production processes, i.e. the melting and casting processes of titanium alloys. The focus is on the production of titanium alloys by the electric arc process, and possible hazards in the production of titanium in electric arc furnaces are also described. Suitable protective measures to be taken in the event of a particular hazard are also highlighted. Concerning the occurrence of possible accidents in the production of titanium, a calculation is also presented that shows how much needs to be invested in protection against possible accidents while maximising profit. Finally, the application and casting process of titanium alloys in dentistry is presented