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This paper investigates different possibilities of measurement and control of pressure in the cryostat filled with liquid nitrogen. Laboratory designed membrane pressure regulator for automatic control of pressure in the range from 0.9 to 1.3 bar gauge in the cryostat is presented. The performance of the special purpose regulator is evaluated through measurement of pressure deviations from set-point value and their effect on thermal conditions in the cryostat. Results are compared to values obtained using manual pressure regulator.

Sveučilište Sjever je jedina visokoškolska institucija u Republici Hrvatskoj koja se uključila u Program energetske obnove zgrada javnog sektora u razdoblju 2014-2020. Nakon provedene cjelovite obnove i opremanja zgrada mjernim uređajima, započeto je istraživanje utjecaja ponašanja korisnika na potrošnju energije praćenjem meteoroloških uvjeta te parametara ugode u prostoru: temperature, relativne vlažnosti (engl. RH), razine ugljikovog dioksida (CO2) te hlapivih organskih spojeva (engl. VOC) sve sa svrhom unaprjeđenja postojećeg modela ugovaranja po energetskom učinku (ESCO model). Prikupljeni podaci mjerenja u sezoni grijanja 2021/2022 (listopad-svibanj) poslužili su kao ulazni podaci za učenje i testiranje acikličke (engl. Feedforward) umjetne neuronske mreže (engl. Artificial Neural Network - ANN) s ciljem izračuna referentne vrijednosti potrošnje energije za grijanje prostora kao i predviđanja potrošnje pri nepoznatim (budućim) meteorološkim uvjetima i uvjetima boravka u prostoru.

Sveučilište Sjever jedina je visokoškolska institucija u RH koja se uključila u Program energetske obnove zgrada javnog sektora u razdoblju 2014. – 2020. Sljedeći korak nakon cjelovite obnove jest istraživanje parametara ugode u prostoru te je u radu opisan način na koji će se uz potrošnju energije pratiti temperatura, relativna vlažnost, razina ugljikova dioksida prisutnog u prostoru, te hlapljivi organski spojevi (VOC) u prostoru. Na temelju toga analizirat će se ostvarenje zajamčenih ušteda i procijeniti potencijal za dodatne uštede.

Sveučilište Sjever je jedina visokoškolska institucija u RH koje se uključila u Program energetske obnove zgrada javnog sektora u razdoblju 2014-2020. Nakon provedene cjelovite obnove, započeto je istraživanje parametara ugode u prostoru, te su u ovom radu opisani načini na koji se uz potrošnju energije prati temperatura, RH, CO2 i VOC u prostoru. U radu su prikazani i prvi rezultati analize navedenih parametara, kao i utjecaj ponašanja korisnika na potrošnju energije. Navedeno će se promatrati u cilju unaprjeđenja postojećeg modela ugovaranja po energetskom učinku (ESCO model).

Za savladavanje maksimalnih toplinskih gubitaka te optimalnog odnosa brzine grijanja i hlađenja unutar tehnološki prihvatljivog vremenskog intervala potrebna je usklađenost male termofizikalne karakteristike niskoakumulativnog objekta – plastenika s racionalnim sustavom grijanja. Za toplovodno termoenergetsko postrojenje toplinske snage 2, 5 MW i toplifikacijski sustav niskoakumulativnog objekta korisne površine 1 ha lociranog u kontinentalnoj Hrvatskoj, utvrđeni su vremenski intervali i ukupna potrošnja biomase pri cjelogodišnjem uzgoju povrća. Pomoću spremnika topline postiže se hidrodinamička i klizna toplinska ravnoteža između izvora topline i sekundarnog ogrjevnog kruga te smanjenje naglih promjena temperature zraka u plasteniku. Provedena su stvarna mjerenja potrošnje biomase i utvrđena je potrošnja toplinske energije pri radu termoenergetskog postrojenja te uspoređeno sa prirodnim plinom za klimatske uvjete i intervale korištenja. Kvantificiranim vrijednostima i provedenom analizom prikazana je energetska učinkovitost i ekonomičnost toplifikacije niskoakumulativnog objekta. Primjena rezultata doprinosi optimalnom dimenzioniranju i racionalnijem projektiranju termoenergetskih postrojenja.

This report presents the results of project Task 2.2 ‘stakeholder mapping’ , which is an important initial step of the project, and has consisted on the identification and analysis of a range of relevant stakeholders in each country. The selection of the stakeholders have followed a preliminary discussion between the partners where the key roles of energy efficient urban regeneration projects were identified, through the different stages of the process, and considering local, regional, national and international levels. The identification of the roles took into consideration inputs from Task 2.1 where the analysis of the framework for urban regeneration was carried. For the selection of stakeholders, it was ensured that they covered the key issues related to legislation and policy, financing, and management of the projects identified in the framework report.

U sklopu UNDP EE projekta – Poticanje energetske efikasnosti u Hrvatskoj, razvijen je sustav daljinskog očitanja potrošnje energije i vode, koji je implementiran na 42 objekata javne namjene diljem Hrvatske. Podaci se automatizirano prikupljaju za sve energente i vodu na satnoj razini sa naplatnih brojila te se šalju u nacionalni Informacijski sustav za gospodarenje energijom (ISGE). Ovaj rad prezentira analizu potrošnje električne energije u ovisnosti o namjeni, funkcionalnim i tehničkim parametrima javnog objekta. U sklopu rada analizirani su četiri tipa javnih objekata: uredska zgrada, bolnica, obrazovna institucija, zatvor. Objekti su analizirani prema tipu i statičkim parametrima korisne površine i broju korisnika.

Glavna namjera istraživanja je neovisno ostvarenje Međunarodne temperaturne ljestvice ITS-90 kroz niz temperaturnih fiksnih tocaka (trojnih tocaka, krutišta i tališta cistih metala) u podrucju od -40 °C do 660 °C, te poboljšanje prenošenja sljedivosti na sekundarne etalone temperature. Ostvarenje temperaturne ljestvice ukljucilo je definiranje eksperimentalne metode za umjeravanje etalonskih termometara primarnom metodom, određivanje matematickog modela umjeravanja i racunanja mjerne nesigurnosti za definiciju u temperaturnim fiksnim tockama i za interpolaciju između tocaka. Predloženo istraživanje poboljšalo je mjerne mogucnost Laboratorija za procesna mjerenja kao \Nacionalnog etalona temperature Republike Hrvatske, te je ostvareno kroz nekoliko znanstvenih i tehnoloških projekata koje je potpomoglo Ministarstvo znanosti i tehnologije. Rezultati neovisne realizacije ITS-90 eksperimentalno su potvrđeni kroz niz međulaboratorijskih usporedbi sa ekvivalentnima europskim nacionalnim etalonima. U podrucju prenošenja sljedivosti na sekundarne etalone ispitan je koncept višeuložne fiksne tocke, te je eksperimentalno potvrđen pozitivan utjecaj na smanjenje nesigurnosti pri usporedbenom umjeravanju termometara. Main goal of investigation is the realization of the International Temperature Scale (ITS-90) using set of the temperature fixed points (triple points, freezing points and melting points of pure metals ) in the range from -40 °C to 660 °C, and improved dissemination of the traceability from realized scale to secondary temperature standards. Realization of the Temperature scale ITS-90 included definition of the experimental method for calibration of primary temperature standards, design of mathematical model for calibration and calculation of the uncertainty of calibration in temperature fixed points and uncertainty of interpolation between fixed points. Proposed investigation improved measurement and calibration capabilities of Laboratory for Process Measurements as Croatian National Temperature Standard, and was supported by Ministry of Science and Technology. Results of calibrations are confirmed through interlaboratory comparisons with other National Measurement Institutes. In field of dissemination of the scale on secondary standards new concept of multientrance fixed point is investigated, and was found it's particulary positive effect on reducing uncertainties in comparison calibration of thermometers.

Current practice in fixed-point calibration recommends usage of furnaces that provide best achievable uniform temperature distribution at the outer segment of the immersed portion of the fixed-point cell. The effect of any inhomogeneous temperature distribution is somewhat unrevealed, and its coverage in literature is insufficient. In order to establish some estimation of the influence of the inhomogeneous furnace temperature distribution to the calibrating process, a numerical study was conducted. The study was conducted using FLUENT software package employing finite volume method on non-structured grids. The problem was considered as axially symmetric. The domain of the calculation consisted of the whole cell volume and its geometry was modeled such to distinguish each of the individual elements of the fixed point cell assembly. The material properties of the assembly elements were treated as temperature dependent, while their surface properties were kept constant. The mathematical model employs transient conductive heat transfer along with solidification model for Zinc so as radiation heat transfer between surfaces in all argon - filled cavities. The effect of natural convection was assumed to be of minor importance and was therefore neglected thus saving significant amount of computational effort. The calculations covered the whole duration of Zinc solidification process. Several variants of boundary conditions at the fixed - point cell's outer surface were applied. The variants distinguish: the homogeneous temperature distribution at the outer skin of the immersed part of the fixed point cell, the plus and minus 1 K/m of gradient added to base temperature distribution in axial direction and the presence or absence of cold-roding. The base outer temperature was kept 1 K below the solidus temperature giving approximately 6 hours of calibration process. The study shows that such linear gradient of +/- 1 K/ m influences the process solely in its duration, prolonging it or shortening it for approximately 20minutes.

This paper describes the new primary low-range dew-point generator at LPM developed in cooperation with MIKES through EUROMET project no. 912. The generator is designed for primary realisation of the dew-point temperature scale from -70 °C to +5 °C. The principle and the design of the generator are described in detail and schematically depicted. Results of the preliminary efficiency tests of it's saturator show that it is efficient enough for a primary realisation of the dew-point temperature scale. Standard uncertainties due to the non-ideal saturation efficiency are estimated to be 0.02 °C.

This paper describes importance of calibrations, measurement traceability and measurement uncertainty in laboratory accreditation and work of inspection bodies. Basic Standards for accreditation and functioning of laboratories and/or inspection bodies require measurement traceability assurance methods as well as measurement uncertainty evaluation procedures to be applied. Furthermore, those procedures are required to be applied in daily work, which is being controlled in yearly assessment of accreditation body. This paper gives overview of requirements according to several standards important for testing laboratories (HRN EN ISO/IEC 17025:2007 ) and inspection bodies (HRN EN ISO 17020:2005). Measurement traceability assurance methods in Croatia are described. Overview of calibration certificates that should be accepted in accreditation process is given.

This paper presents characterization of diving-bell manometer in the gauge pressure range from -1.0 up to 3.0 kPa in the Croatian national pressure laboratory - Laboratory for Process measurement (LPM), located at the Faculty of Mechanical Engineering and Naval Architecture (FSB), University of Zagreb. The work points out comparison of two independent methods for diving-bell effective area determination i.e. determination based on dimensional measurements as well as determination of the effective area by a pressure comparison method. The dimensional measurements were performed in the Croatian national length laboratory, also at FSB. Determination of the effective area by the pressure comparison method was performed in LPM using a Physikalisch-Technische Bundesanstalt (PTB) Rosemount pressure transducer previously calibrated in PTB Braunschweig. From the results it can be seen that the difference in the effective areas obtained with the two independent methods is very small compared to the estimated effective area measurement uncertainties.

It is good calibration practice to test thermocouples for homogeneity of the Seeback’ s coefficient during calibration process. If change in homogeneity the coefficient, commonly known as inhomogeneity is not detected, thermometer although calibrated might not be able to measure temperature correctly. Several different testing techniques are developed, depending on type of the thermocouple and the equipment available. In order to automate process of thermocouple inhomogeneity testing for all applicable testing methods a Thermocouple Inhomogeneity Testing Device was developed in Laboratory for Process Measurement (LPM), University of Zagreb. The device is mostly used for the testing of thermocouple inhomogeneity in conjunction with heater moving along the thermocouple. The sled for mounting of the heater or the thermometer is translated by a threaded shaft and a step motor in horizontal axis, vertical axis or its sliding direction can be tilted in six steps between those two positions. Sled is mounted on shafts guides with precision linear ball bearing, which allow for smooth translation. The frame of the device is designed with adjustable height and distance between legs, which allows testing in most available metrological baths or furnaces. System is controlled by custom made program on LabView platform, with ability to automatically acquire, store and analyze data test data. Variation of the thermovoltage recorded during measurement is used in calculation of the uncertainty of the calibration. This paper describes the techniques for inhomogeneity testing and design of the testing device. Interpretation of the measurement results and calculation of inhomogeneity related component of the uncertainty budget is presented

It is common practice in thermometry to test the thermocouple which is to be calibrated for homogeneity of Seeback’ s coefficient. In order to facilitate that task and save time in calibration of thermocouples, 3 years ago a Thermocouple Inhomogeneity Testing Device was developed in Laboratory for Process Measurement (LPM), University of Zagreb. The device is primarily used for the testing of thermocouple inhomogeneity (either with moving heater or for gradual immersion of thermocouple into isothermal zone). It can be also used for estimation of axial gradients in isothermal zones and hydrostatic head effects in fixed points. The sled for mounting of the heater or the thermometer is translated by a threaded shaft and a step motor in horizontal axis, vertical axis or its sliding direction can be tilted in six steps between those two positions. Sled is mounted on shafts guides with precision linear ball bearing, which allow for smooth translation. The frame of the device is designed with adjustable height and distance between legs, which allows testing in most available metrological baths or furnaces. System is controlled by custom made program on LabView platform, with ability to automatically acquire, store and analyze data test data. This paper describes the design of the testing device. The example results are also presented.

The objective of this paper is to present the methodology for estimation of measurement uncertainties in comparison calibration of thermocouples used at Laboratory for Process Measurements (LPM). The methodology is applied for comparison calibration of rare-metal and industrial base-metal thermocouples within temperature range from – 20°C to 660°C with LPM standard/working standard platinum resistance thermometers and from 600°C to 1050°C with LPM standard/working standard thermocouples.

Laboratory for Process Measurements at the Faculty of Mechanical Engineering and Naval Architecture is assigned to be the holder of National standards for thermodynamic temperature and pressure. Beforehand Laboratory was successfully accredited by DAR/PTB/DKD (Deutscher Akkreditierungs Rat / Physikalisch-Technische Bundesanstalt / Deutsche Kalibrierdienst) accreditation service according to standard ISO/IEC 17025 for temperature and pressure measurands. In this paper, Laboratory temperature standards, temperature measurement systems and best measurement capabilities in the whole range from -20 to 1050°C are described with special emphasis on how the traceability of temperature in Croatia is assured. Future developments of the national laboratory related to independent realization of part of temperature scale are described.

This paper presents the modelling methodology for estimation of measurement uncertainties in comparison calibration of thermocouples used at Laboratory for Process Measurements (LPM). The methodology is applied for comparison calibration of noble and industrial base-metal thermocouples. The calibration standards used in examples are platinum resistance thermometers up to 660°C and standard/working standard thermocouples from 600°C to 1050°C

This paper presents a simplified model for the evaluation of the measurement uncertainty of pressure balance effective area calibrated by method of comparison which is being applied at Laboratory for Process Measurements (LPM). The methodology is applied for oil-operated industrial pressure balances in the gauge pressure range up to 60 MPa. The scope of the procedure is illustrated by calculation example.

Rad obuhvaća sažetu povijest mjerenja i nastanak metričkog sustava, pregled osnovnih pojmova i znanja vezano za toplinsku ekspanziju materijala, toplinska svojstva materijala i istezanje materijala pri toplinskoj obradi i hlađenju. Kao primjer za potrebe rješavanja zadatka rada, odabran je staklarski alat i pripadajuća mjerna oprema koja se koristi za kontrolu staklarskog alata. U praktičnom dijelu opisana je završna kontrola staklarskog alata. Opisani su svi procesi završne kontrole od potrebne dokumentacije do završnog dijela sklopa alata. Provedeno je ispitivanje utjecaja temperature na alat za proizvodnju staklene ambalaže. Cilj rada je utvrditi utjecaj temperature na dimenzije alata za proizvodnju staklene ambalaže, tj. je li pri obradi došlo do dilatacije materijala. This paperwork includes a brief history of measurement and the emergence of the metric system, an overview of basic terms and knowledge related to the thermal expansion of materials, thermal properties of materials and elongation during thermal treatment and cooling. A glassmaking tool and the associated measuring equipment used to control the product were selected as a example. In the practical part, the final control of the glassmaking tool is described. All final control processes are described, from the necessary documentation to the final part of the tool assembly. A test of the effect of temperature on the tool for the production of glass packaging was carried out. The aim of the work is to determine the influence of temperature on the dimensions of tools for the production of glass packaging, i.e. whether the material was deformed during processing.

U prvom dijelu diplomskog rada raščlanjene su i opisane postojeće trokoordinatne mjerne metode. Objašnjena je primjena 3D skenera u industriji, kao i terminologija koja se veže uz reverzni inženjering i kontrolu kvalitete. Opisane su karakteristike i mogućnosti Creaform HandySCAN BLACK™ | Elite 3D skenera te pripadajućeg VXelements programskog paketa koji se koriste za provedbu eksperimentalnih mjerenja. Objašnjena je kalibracija prema VDI/VDE 2634 Dio 3 smjernici, kao i postupak kalibracije pomoću kalibracijske ploče. U eksperimentalnom dijelu obrađen je utjecaj promjene temperature okoliša na distorziju predmeta. Prvi eksperiment sastoji se od 3D skeniranja pozicije u standardnim mjeriteljskim uvjetima (20 ℃) te u uvjetima povišene temperature (33 ℃). Izvršena je FEA analiza toplinskog širenja, nakon čega su svi rezultati uspoređeni. U drugom eksperimentu izvršeno je mjerenje lokalno zagrijanog predmeta nakon čega je analizirana deformacija. In the first part of the thesis, the existing three-coordinate measurement methods are analyzed and described. The application of 3D scanners in industry is explained, as well as terminology related to reverse engineering and quality control. The characteristics and capabilities of Creaform HandySCAN BLACK™ | Elite 3D scanner and associated VXelements software package are described, which are used to perform experimental measurements. Calibration according to the VDI/VDE 2634 Part 3 guideline is explained, as well as the calibration procedure using the calibration plate. In the experimental part, the influence of the change in temperature of environment on the distortion of the object was analyzed. The first experiment consists of 3D scanning the position in standard measuring conditions (20 ℃) and in elevated temperature conditions (33 ℃). An FEA analysis of thermal expansion was performed, after which all results were compared. In the second experiment, a locally heated object was measured, after which the deformation was analyzed.

U ovom radu obrađena je Sunčeva energija, insolacija i njena raspršenost (difuzija) na Zemljinu površinu. Također, prikazana je karta Hrvatske u ovisnosti srednje godišnje ozračenosti na vodoravnu plohu, a spominje se i povijest uporabe Sunčeve energije i razvoja fotonaponskih ćelija. Razmatra se i tehnologija, odnosno princip rada fotonaponskih ćelija te je objašnjen fotoelektrični efekt. Na kraju teoretskog dijela rada spominje se podjela fotonaponskih ćelija, od starijih tehnologija, kao što su silicijske ćelije, do novijih, koje imaju veću iskoristivost, ali su znatno skuplje i trenutno preskupe za komercijalnu upotrebu. Također se razmatraju prednosti i mane On-Grid i Off-Grid fotonaponskog sustava. U drugom dijelu, napravljen je proračun Off-Grid fotonaponskog sustava i usporedba isplativosti takvoga sustava za različite cijene goriva i električne energije. Na kraju su izneseni zaključci te moguća poboljšanja koja se mogu uvesti.

U ovome radu opisan je tijek tehničkog pregleda vozila i napravljena je usporedba rezultata dobivenih pregledom istog automobila u dvjema stanicama za tehnički pregled. Cilj istraživanja bio je opisati postupak tehničkog pregleda i usporediti rezultate mjernih uređaja. Stanice za tehnički pregled opremljene su uređajima propisanim u Pravilniku o tehničkim pregledima. Mjerenja su napravljena u stanicama za tehnički pregled vozila STP „AUTOCENTAR VRBOVEC“, Vrbovec i STP „CROATIA-TEHNIČKI PREGLEDI“, Čazma. Korišten je uređaj za mjerenje točke isparavanja kočione tekućine, uređaj za mjerenje ispušnih plinova, te uređaj s valjcima i testerom ovjesa koji mjeri kočne sile i stupanj prigušenja amortizera. Usporedbom rezultata mjerenja dobivenih u stanicama za tehnički pregled vozila donesen je zaključak o odstupanju i razlici dobivenih rezultata mjerenja. Također je napravljena usporedba dobivenih rezultata mjerenja provedenih na dva mjerna mjesta. This paper describes the course of technical inspection of vehicles and compares the results obtained by inspection of the same car in two different stations for technical inspection. The aim of the research was to describe the technical inspection procedure and compare the results of measuring devices. Stations for technical inspection of vehicle are equipped with devices prescribed in the Ordinance on technical inspections. Measurements were made in the stations for technical inspection of vehicle STP "AUTOCENTAR VRBOVEC", Vrbovec and STP „CROATIA-TEHNIČKI PREGLEDI, Čazma. A device for measuring the evaporation point of the brake fluid, measuring the exhaust gases, a device with rollers and a suspension tester that measures the braking forces and the degree of damping of the shock absorber were used. By comparing the measurement results obtained in the stations for technical inspection of vehicle, a conclusion was made about the deviations and differences of the obtained measurement results. A comparison of the obtained measurement results carried out at the two measuring points was also made.

U suvremenim poduzećima sve se veća važnost pridaje različitim mjerenjima i analiziranju dobivenih rezultata. Kroz ovaj rad prikazana je priprema i ovjera membranskih plinomjera kao trenutno jednih od najkorištenijih mjerača protoka plina u Hrvatskoj, ali i u svijetu. Svrha ovog diplomskog rada je prikazati teorijske okvire odnosno logičke modele i zaključke do kojih se došlo različitim istraživanjima, a koji pridonose razumijevanju pripreme i ovjere membranskih plinomjera. Nadalje, prikazani su i brojni zakoni, pravilnici i drugi zahtjevi koji su nužni za razumijevanje analiziranog područja. U radu je provedena detaljna analiza pripreme i ovjere plinomjera, na primjeru membranskog G4 plinomjera u poduzeću Termoplin d.d. Varaždin koja može poslužiti kao pozitivan primjer kontinuiranog unaprjeđenja i razvoja ovog područja. Analiza prikazanih podataka upućuje na to da su priprema i ovjera plinomjera zaista od iznimne važnost za poslovanje poduzeća koja se bave ovom djelatnošću. Kao ključno pitanje u ovom radu ističe se mjera nesigurnost uređaja kojima se ispituju plinomjeri koja zaista utječe na različite aspekte poslovanja poduzeća. In modern companies, increasing importance is attached to various measurements and analysis of the results obtained. This master's thesis presents the preparation and verification of diaphragm gas meters as currently the only one of the most used gas flow meters in Croatia, but also in the world. The purpose of this thesis is to present the theoretical framework respectively logical models and conclusions reached by various studies, which contribute to the understanding of the preparation and verification of membrane gas meters. Furthermore, a number of laws and regulations that are necessary to understand the analyzed area are presented. The master`s thesis performs a detailed analysis of the preparation and verification of gas meters, on the example of a diaphragm G4 gas meter in the company Termoplin d.d. Varaždin, which can serve as a positive example of continuous improvement and development of this area. The analysis of the presented data indicates that the preparation and verification of gas meters are indeed extremely important for the business of companies engaged in this activity. A key issue in this master`s thesis is the measurement uncertainty of the devices used to test gas meters, which really affects various aspects of the company's business.

Predmet ovog diplomskog rada bio je objedinjavanje postojećih standardnih dijelova namještaja (podnica, madraca, okova i mehanizam ...) , u jednu novu „familiju“ proizvoda , tako zvanog kombiniranog namještaja. Prikazan je tijek nastanka gotovog proizvoda od ideje do prototipa koji je realiziran. Koncept sofa-krevet-ormar nije novost kao takav, nego je novost kombinacija funkcionalnosti, ergonomičnosti, dizajna i tehnoloških rješenja. Prezentirani prototip sadrži krevet, francuski ležaj standardnih dimenzija 180 x 200 cm, sofu sa naslonima za glavu (jastucima ) , bočne ormare i spremište za posteljinu. Sa prednje strane je i polica koja se zajedno sa nogom kreveta spušta bez da se stvari koje su na polici miču. Mehanizam za pokretanje realiziran je sa 3 linearna pogona, jedan za dizanje i spuštanje sofe , a dva za dizanje i spuštanje kreveta. Na kraju provedena je opsežna analiza životnog ciklusa proizvoda. Za prototip je prikazana i analiza cijene koštanja takvog proizvoda i mogućnosti plasmana na tržište he subject of this thesis was the integration of existing standard pieces of furniture (flooring, mattresses, fittings and mechanism...), into a new "family" of products, the so-called combined furniture. The course of creation of the finished product from the idea to the prototype that is realized is shown. The sofa-bed-wardrobe concept is not a novelty as such, but a novelty is a combination of functionality, ergonomics, design and technological solutions. The presented prototype contains a bed, a double bed of standard dimensions 180 x 200 cm, a sofa with headrests (pillows), side cabinets and linen storage. On the front side, there is also a shelf that goes down together with the foot of the bed without the things on the shelf moving. The starting mechanism is realized with 3 linear drives, one for raising and lowering the sofa, and two for raising and lowering the bed. Finally, a comprehensive product life cycle analysis was performed. For the prototype, an analysis of the cost price of such a product and the possibility of marketing it is presented.

Ovaj rad prikazuje inovativan način mjerenja relativno krutih i deformabilnih proizvoda. Rad se sastoji od uvoda i tri praktična primjera na kojima je prikazana primjena optičkog pozicioniranja, virtualnog stezanja i virtualnog stezanja s kompenzacijom gravitacije. Na početku rada napravljen je uvod u optičko mjeriteljstvo. Prikazani su osnovni podaci za ATOS 5 optički 3D skener, automatiziranu ćeliju ScanBox 5120 i PlusBox koji su korišteni u praktičnom dijelu rada. Navedena su područja primjene rezultata 3D skeniranja kao i osnovni principi rada ATOS 3D skenera. Prvi praktični dio prikazuje optičko pozicioniranje naprave za 3D skeniranje. Cilj je smanjiti odstupanja stvarne naprave od idealnog CAD modela. Optičko pozicioniranje koristi se za preciznu montažu komponenti u prostoru. Praćenjem pozicije komponente u odnosu na referencu moguće je uživo vidjeti odstupanja u mapi boja kao i odstupanje normala točaka čije odstupanje želimo namjestiti u definiranu tolerancijsku zonu. Drugi dio praktičnog rada prikazuje mjerenje proizvoda od čeličnog lima u napravi za 3D skeniranje. Pretpostavka je da na geometriju proizvoda nema značajnog utjecaja temperature ili gravitacije zbog debljine čeličnog lima i geometrije proizvoda. Postupkom virtualnog stezanja odstupanje normale stezne točke, u RPS poravnanju, simulacijom se dovodi unutar tolerancijske zone stezne točke. Simulacijom je dobivena sila stezanja te je za kontrolu simulacije sila stezanja primjenjena na čelični lim pomoću opružnog dinamometra. Treći dio praktičnog rada bavi se problematikom mjerenja deformabilnih proizvoda. Relativno veliki i tanki limovi te polimerni proizvodi prilikom mjerenja se oslanjaju na napravu za mjerenje ili kontrolnik. Sila gravitacije uzrokuje deformaciju takvih proizvoda. Virtualnim stezanjem s kompenzacijom gravitacije proizvod se mjeri u slobodnom stanju. Zatim se simulacijom oduzima utjecaj gravitacije. Potom se proizvod translatira u montažnu poziciju te se dodaje utjecaj gravitacije. Na poslijetku se simulacijom odstupanje steznih točaka dovodi u nominalno stanje. This paper shows inovative way of measuring rigid and deformable products. It consists of intoduction and three practical examples. Practical part shows workflow for optical positioning, virtual clamping and virtual clamping with gravity compensation. Introduction into optical metrology informs reader about basic working principles of ATOS 3D scanner and other measuring systems that were used in practical part of this paper. First practical part shows optical positioning of fixture used for 3D scanning. The goal of optical positioning is reducing deviation of real fixture compared with CAD data. Optical positioning is used for precise assembly of the parts in space. Tracking position of component in respect to reference, in live view, deviation of the real part in respect to nominal data can be visualised in a color plot. Also, deviation of surface points is shown in real time so position of each component can be adjusted acording to nominal data. Second practical part shows measuring rigid sheet metal part in 3D scanning fixture. Main assumption in this part is that temperature and gravity does not have significant influence on geometrie of the part. Procedure called virtual clamping is used to reduce deviation of clamping point to zero using FEM simulation. Holding points are defined as RPS points of the part. Result of the simulation is deviation of clamping point inside iteration tolerance and clamping force. To verify results of virtual clamping, clamping force was aplied on the sheet metal and the part was measured to compare virtually and mechanically clamped part. Third practical part shows solution from GOM for measuring deformable parts. Relatively large and thin sheet metal parts, as well as plastic parts, are usually measured on fixtures for measuring or gauges. While part is being measured, influence of gravity can cause deformation of the part. Using procedure called virtual clamping with gravity compensation, part is measured in the free state. After measuring in free state, influence of gravity is removed using FEM simulations. Next step is translating the part into RPS alignment and adding influence of gravity in assembly situation. Final step is virtual clamping using predefined clamping points and reducing deviation of clamping points inside iteration tolerance zone.

U ovom završnom radu opisani su koordinatni mjerni uređaji za mjerenja u proizvodnji, napravljena je osnovna podjela koordinatnih mjernih uređaja, opisana njihova izvedba i primjena. U poseban tip koordinatnih mjernih uređaja spadaju 3D mjerne ruke koje se u današnje vrijeme sve više koriste u svim fazama proizvodnje. Za potrebe završnog rada odrađeno je mjerenje u Metalskoj industriji Varaždin. Mjerenje je izvršeno uz pomoć 3D mjerne ruke s laserom, skeniran je eliptični zasun DN150 PN16. Rezultati mjerenja uspoređeni su s CAD modelom u svrhu dobivanja odstupanja stvarnog komada i modela. In this final paper are coordinated measuring devices for measurements in production described, the basic classification of coordinated measuring devices is made, their design and applications are described. A special type of coordinated measuring devices includes 3D measuring hands which are nowadays increasingly used in all phases of production. For the needs of this final paper, the measurement was performed in the Metal Industry Varaždin. The measurement was performed using a 3D measuring arm with a laser, an elliptical latch DN150 PN16 was scanned. The measurement results were compared with the CAD model for the purpose of obtaining the deviation of the actual piece and the model.

U ovom radu napravljena je analiza i mjerenje proizvoda koji je razvijen i proizvodi se u Metalskoj industriji Varaždin. Cilj istraživanja bila je usporedba mjernih postupaka i protokola mjerenja u tvrtki koja se bavi strojnom obradom, te ima vlastitu ispitnu stanicu i mjerni laboratorij. Istraženo je područje mjeriteljstva u kojem se koriste nove tehnologije poput ticala, lasera, skenera i sličnih inovativnih mjernih uređaja i alata. U Metalskoj industriji Varaždin napravljeno je mjerenje „klasičnim“ mjernim uređajima kao što su mikrometar, imikron, digitalno pomično mjerilo, kutomjer, ali i modernom tehnologijom, odnosno mjernom rukom. Pomoću mjerne ruke napravljena je izmjera proizvoda, ali i skeniranje, te usporedba s 3D modelom. Usporedbom rezultata dobivenih različitim mjernim postupcima donesen je zaključak o točnosti, preciznosti i brzini mjerenja, odnosno o razlici navedenih osobina između svakog pojedinog načina mjerenja i kontrole proizvoda prilikom obrade. Također, napravljena je i usporedba cijena svakog od načina mjerenja.

Ovaj završni rad opisuje dimenzionalno mjeriteljstvo u cilju osiguranja kvalitete bravarskih proizvoda u različitim fazama proizvodnje. Da bi se što bliže dočaralo što to konkretno znači, u prvom dijelu rada govori se općenito o pojmu same kvalitete. S obzirom da se radio o vrlo „širokom“ području, za početak, opisuje se povijest kvalitete i njen utjecaju na čovječanstvo, zatim opisuju se faze razvoja kvalitete i prilagodbe s obzirom na tadašnje okolnosti, opisana je i kvaliteta kakvu danas poznajemo, odnosno kvaliteta 21. stoljeća. Nadalje, govori se o teorijskim karakteristikama kvalitete, što obuhvaća upravljanje kvalitetom, kontrolu kvalitete, osiguranje iste i na kraju pokazatelji kvalitete. U četvrtom poglavlju opisuje se pojam mjeriteljstva, razvoj, standardizacija i usklađenja kroz povijest i velik utjecaj koji mjeriteljstvo ima na kvalitetu, odnosno upravljanje kvalitetom. U petom poglavlju u kratkim crtama opisuju se osnovni pojmovi mjeriteljstva i mjerenja. U praktičnom dijelu rada koji počinje od šestog poglavlja opisuje se kontrola kvalitete u odabranom proizvodnom poduzeću, konkretno se radi o poduzeću EKO MEĐIMURJE d.d. Nakon nekoliko rečenica o samom poduzeću, opisuje se upravljanje kvalitetom u poduzeću. Od ovlaštenja i odgovornosti do same organizacije. Poseban naglasak stavljen je na međufaznu kontrolu bravarskih proizvoda u različitim fazama proizvodnje. Opisuje se plan na čijoj osnovi se provodi kvaliteta međufazne kontrole. Nadalje, prikazani su konkretni primjeri međufazne kontrole sa mjernim alatima i pomagalima. Nadalje, govori se o mjernoj opremi u poduzeću. S obzirom da su mjerni uređaji, alati i pomagala neizbježni za kontrolu bravarskih proizvoda, opisuju se ovlaštenja i odgovornosti, organizacija i opis postupaka kontrole točnosti mjerne opreme. Prikazani su konkretni primjeri umjeravanja mjerne opreme koja se najčešće koristi u proizvodnji.

U ovom radu opisan je rad solarnog sustava, potrebne komponente solarnog sustava te proračun isplativosti ugradnje solarnog sustava prema normi HRN EN 15316-4-3. U prvom djelu opisana je norma HR EN 15316-4-3 koja sadrži metodu B za izradu proračuna isplativosti ugradnje solarnih kolektora za zagrijavanje PTV-e i grijanje prostora. Drugi dio se odnosi na detaljan proračun isplativosti ugradnje solarnih kolektora na području grada Varaždina za obiteljsku kuću. Dok su u zadnjem djelu opisane odabrane komponente solarnog sustava i zaključak o investiranja u solarni sustav. The paper describes the operation of a solar system, the required solar system components, and the calculation of the cost-effectiveness of the solar system implementation according to HRN EN 15316-4-3. The first part describes the standard HR EN 15316-4-3, which contains Method B for calculating the cost-effectiveness of installing solar collectors for DHW heating and space heating. The second part refers to a detailed calculation of the cost-effectiveness of installing solar collectors in the Varaždin urban area for a family house. The final part of the paper deals with selected components of the solar system and the conclusion about investing in the same.

Zahtjevi za preciznost u suvremenoj proizvodnoj industriji doveli su do situacije da se trokoordinatni CNC mjerni uređaji nalaze u gotovo svim velikim, a nalazimo ih već i u manjim radionicama. Međutim, većina tih strojeva koristi se kao alat za ispitivanje gotovih proizvoda, da li isti zadovoljavaju određene specifikacije, obično primjenjujući opće pravilo da nesigurnost mjerila ne smije biti veća od jedne petine (idealno desetine) izmjerene vrijednosti. U ovom se radu opisuje usporedba takvog načina generalno usvojenim načelom i izračunate ponovljivosti i obnovljivosti CNC mjernog stroja. Usporedba se provodi u stvarnom radnom okruženju sa stvarnim proizvodima. The requirements for precision in modern manufacturing industry has led to situation where three coordinate CNC measuring machines are found in almost all but smallest workshops. However, majority of those machines are used as inspection tool for pass/fail tests, usually applying general rule that the measuring machine uncertainty should be no more than one-fifth (ideally one-tenth) of measured value. In this paper comparison between such rule of the thumb approach and calculated reproducibility and repeatability of the measuring machine will be described. Comparison is performed in real work environment with actual products.

Ovaj rad prikazuje postupak mjerenja odljevka manualnim i automatiziranim 3D optičkim sustavom ATOS. U radu su objašnjeni osnovni principi rada optičkog skenera, pravila koja treba slijediti prilikom skeniranja i postupak obrade rezultata prema zadanom nacrtu i dobivenim rezultatima. Prikazom manualnog skeniranja ideja je provesti čitatelja kroz postupak mjerenja optičkim skenerom ATOS Core od kalibracije pa sve do gotovih rezultata u obliku poligonizirane mreže .stl formata. Navedena su pravila koja treba poštovati kako bi rezultat mjerenja bio točan i precizan. Postupak manualnog skeniranja uvod je u automatizirani postupak te prikazuje bazu znanja koja se koristi kod automatizacije mjernog postupka. Automatizirani postupak skeniranja prikazan je na mjernoj ćeliji ATOS ScanBox 4105. Za postupak automatizacije konstruirana je naprava za pozicioniranje odljevka u mjernu ćeliju. Naprava za pozicioniranje napravljena je kombinacijom standardiziranih aluminijskih profila i 3D printanih dijelova koje geometrijskim oblikom prihvaćaju odljevak na rotacijski stol mjerne ćelije. Nadalje, prikazan je ručni i automatizirani način generiranja pozicija iz kojih je izvršeno mjerenje odljevka. Postupkom automatizacije mjerenja prikazano je offline programiranje, simulacija mjerenja, izrada naprave za pozicioniranje, mjerenje automatiziranim sustavom ATOS Scanbox 4105 i evaluacija parametarskih rezultata u virtualnoj mjernoj sobi. This paper shows measuring workflow for casted bearing cover using manual and automated optical measuring systems ATOS. Theoretical part of this paper shows basic principles of optical scanner while practical part establishes the rules to be followed during the scanning, scanning process and parametric inspection of the results based on mechanical plan. By displaying manual scanning, the idea is to implement reader through the calibration of ATOS Core optical scanner, all the way to the final results in the form of a polygonized network of points in .stl format. There are rules to be followed so that the measurement result is precise and accurate. The manual scanning procedure is an introduction to the automated process and shows the knowledge base used in automation of the measuring process. The automated scanning procedure is displayed on the ATOS ScanBox 4105 measuring cell. For the automated measurements, a casted bearing cover is placed in the measuring cell on fixture located on the rotation table in measuring cell. The fixture is made out with a combination of standardized aluminum profiles and 3D printed parts that geometrically fit casted bearing cover. Furthermore, a manual and automated way of generating measurement positions is shown. The offline programming, simulation of measurement, assembly of the fixture, measurements and parametric evaluation of scanned results in the virtual measuring room is displayed through automation of measuring process.

Pojam kvalitete nekog proizvoda označava zadovoljstvo kupca tim istim proizvodom. Upravo kod tog mjerenje ima vrlo bitnu ulogu u samom procesu proizvodnje. Zbog sve većeg zahtjeva kvalitete neophodno je poticati daljnja istraživanja u tehnikama mjerenja. Sa sve većim brojem CNC strojeva, porasla je potražnja za uređajem koji bi puno brže i preciznije izmjerio dimenzije radnog komada. Trokoordinatni mjerni uređaj ima veliku ulogu u kontroli kvalitete. Osim jako visoke preciznosti i točnosti, neke od prednosti uređaja su fleksibilnost, manji utjecaj čovjeka te uvećana produktivnost. Tema ovog završnog rada je mjerenje dimenzija dva gotova proizvoda pomoću trokoordinatnog mjernog uređaja. Rad se sastoji od teoretskog i eksperimentalnog dijela. U radu je opisana izvedba samog trokoordinatnog mjernog uređaja, karakteristike različitih mjernih sondi te načini programiranja i upravljanja uređajem. U svrhu ovog rada izvedeno je i mjerenje i tvrtki NABA Technology d.o.o. na WENZEL XO 87 trokoordinatnom mjernom uređaju. The term quality of a product means customers satisfaction with the same product. Precisely at this measurement, it has a very important role in the production process itself. Due to increasing quality requirements it is necessary to encourage further research into measurement techniques. With the increasing number of CNC machines, demand for the device grew faster and more precisely to measure the dimensions of the work piece. A coordinated measuring device playsa major role in quality control. Apart from the high precision and accuracy, some of the advantages of the device are flexibility, lowered human impact and increased productivity. The theme of this paper is to measure the dimension of two finished products using a coordinate measuring machine. The paper consists ofa theoretical and experimental part. It describes the performanceof a coordinate measuring machine itself, the characteristics of different measuring probes, and the way of programming and controlling the device. For the purpose of this paper, measurement was also performed at NABA Technology d.o.o. on the WENZEL XO 87 coordinate measuring machine.