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Weight control of soft cheese formed on a manual production line
Páral, Marek ; Zemanová, Jana (referee) ; Tomečková, Šárka (advisor)
The thesis deals with the control of the weight of soft cheeses during molding on a manual line. The theoretical part describes the classification of cheeses into groups, the basic characteristics of soft cheeses and their representatives. Furthemore, the whole technology of soft cheese production is processed and the effects on curd formation and factors influencing the weight of cheeses during molding are explained. The theoretical part ends with the basics of statistics for data processing. Basic measuring techniques (dry matter measurement, pH measurement, measurement of temperature and weight) were selected to determine the technological parameters (pH of whey, pH, dry matter and temperature of cheese grain, weight of cheese etc.) to describe the quality of grain in the experimental part of the thesis. The Design of Experiments method was used to find the optimal setting of the molding machine. Three partial experiments were designed and done. Results were verified in real production. The pH of whey was chosen to describe the grain quality. Two factors have been discovered that have a significant effect on the weigh of cheeses during molding, namely the position of the operator during molding and the amount of whey flowing into the forms with the cheese grain. The proposed molding modifications were successfully tested in production and no statistical difference was found between the weight of cheeses formed with the new setting of molding machine.
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Obtaining and complex charaterization of Plectranthus spp. extracts
Boboková, Alexandra ; Saláková, Alena (referee) ; Vítová, Eva (advisor)
Plectranthus amboinicus is a herb that was found to have a lot of bioactive compounds, most of them are polyfenolic compounds. Extraction is neccesary to obtain bioactive compounds and to use them subsequently in food or cosmetic industry. Three methods of extraxtion – maceraction, PHWE and PFE, were used in this study. The best yield of extracted polyfenols was observed by maceration. Maceration was, in the next step, optimized using mathematical statistical method of planned experiment (DOE). The optimal conditions found for extraction were: temperature 60 °C, solvent 40% ethanol, time 90 minutes, solid-solvent ratio 1:10. Total phenolic compunds content in this extract was 0,18 ± 0,05 mgGAE·ml-1, which means 1,83 ± 0,53 mgGAE·g-1 of plant. The antioxidant activity was 148,69 ± 26,92 gTEACml-1. Percentage of radical scavenging activity ABTS•+ was 30,03 ± 5,44 %. Further, 27 of volatile aroma compounds were identified in optimal extract, the most important were: -selinene (16,67 %), trans--bergamotene (14,22 %), caryophyllene (14,11 %), 3-carene (8,22 %), -copaene (7,55 %), -terpinene (6,28 %), humulene (5,87 %), cadina-1(10)-4-diene (5,19 %).
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Foaming of fermentation residues during a vacuum evaporation
Knob, Jan ; Brummer, Vladimír (referee) ; Vondra, Marek (advisor)
The diploma thesis deals with the processing of digestate, which is the remaining material after biogas production. It aims to experimentally prove how chosen operational parameters of antifoaming agents influence digestate foaming associated with the vacuum evaporating technology. Based on the research of available antifoamers and the issue of digestate foaming itself, it was observed how three selected antifoamers (i.e. rapeseed oil, silicone antifoamer Erbslöh Schaum-ex and oleic acid), together with the decrease in the pH factor of the evaporating digestate, influence the final foam production. For the purposes of the research, an apparatus simulating the vacuum evaporating process was set up in which the heated sample was brought to boil by gradual pressure decrease. The process of foaming was observed in a transparent cylinder of a testing culumn. The essential part of the experimental activity is represented by a planned experiment which by means of a DoE (Design of experiments) method proved rapeseed oil to be very efficient. In contrast, other antifoamers, as well as the influence of the pH factor decrease, manifested themselves as insignificant factors, while the oleic acid even supported the foaming. The supplementary measurements led to a more detailed research of the effects of rapeseed oil and to the construction of a mathematical model describing how the concentration of rapeseed oil undermines the amount of generated foam. The main contribution of the thesis is firstly the evidence that rapeseed oil plays an important part in the reduction process of digestate foaming and secondly the determination of minimum substance concentration leading to the foaming reduction of a particular sample which is considered efficient enough to enable functioning of a vacuum evaporator. The thesis has also experimentally demonstrated the influence of some polymer organic flocculants which have been proved to support the foaming.
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Elimination of internal stress in the polycarbonate moldings
Selucký, Jaroslav ; Hrbáček, Jan (referee) ; Chladil, Josef (advisor)
This diploma theses raises the issue of internal tension in two-component outer lense, which are made by injection of polycarbonate. The theses gives a more detail view on treatment of the lenses in heating ovens. Heating ovens have been used for decreasing the internal tension in lenses. The subject of the experiment is to determine the influences of the adjustable parameters of the heating oven. The Experiment will be taken by DoE method. The influence of the adjustable parameters is researched and compared among the two types of outer lense with different type of design.
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Design of Experiment for Non-Stationary Processes of Production
Jadrná, Monika ; Macák, Tomáš (advisor)
The doctoral thesis is concerned with the services sector and the area of mass production. Particularly, the optimization of the product portfolio of the travel agency and the optimization of production rounds of ammunition.
The theoretical part deals with the current overview of discussed topic. Further, the terminology and methods of the decision-making process are defined to support decision making. The theoretical basis of research focused on the choice of appropriate input variables in the area of services, and on the choice of a particular material option in the production area and appropriate equipment for the production. The theoretical part forms the basis for the practical part of the thesis.
For the doctoral thesis was chosen an enterprise operating in the defined sector. Product portfolio for the services sector is optimised using Fuzzy logic and Fuzzy sets so that the enterprise can maintain its competitiveness in todays highly ambitious market. Product portfolio for manufacture is optimised for achieving desired properties of the product.
The main aim of the thesis is to propose a new methodological approach for the management of selected business processes in their nonstationary time course. The aim of the practical implementation is to verify the functionality of the proposed methodological approach, both in the area of services and in the field of mass production.
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Design of Experiment
Holec, Tomáš ; Popela, Pavel (referee) ; Bednář, Josef (advisor)
In this thesis, the design of experiment is studied. Firstly, a theoretic background in mathematical statistics necessary for understanding is built (chapter 2). The design of experiment is then presented in chapters 3 and 4. Chapter 3 is divided into several subchapters in which its brief history is provided as well as its complex theoretic description (basic principles, steps for planning, etc.). Chapter 4 deals with particular types of the design of experiment (Factorial experiments or Response surface design). Simple examples are provided to illustrate the theory in chapters 3 and 4. Last part of the thesis is strictly practical and focuses on an application of the theory for particular data sets and its evaluation (chapter 5).
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Operational safety of mobile robots in indoor environment
Vojta, Jakub ; Věchet, Stanislav (referee) ; Krejsa, Jiří (advisor)
During cooperation with the Bender Robotics company a need for operational safety assessment of an autonomous mobile robot (AMR) emerged. Operational safety evaluation is a step towards mass production of the studied robot. Market entry of a product requires a string of various actions and safety assessment is one of them. For risk identification and severity rating were used legal requirements, best practice given by standards, FMEA method, experiment and RIPRAN method. Threats, possible scenarios and risks analysis is systematically discussed through all areas of operation of the robot, from design and construction to control software. All the steps are described in logical order. Starting with information research, going on with series of analysis and ending with suggestions for increased operational safety of autonomous mobile robots.
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Production process optimization
Drábková, Veronika ; Jankových, Róbert (referee) ; Fiala, Alois (advisor)
This master´s thesis is aimed at the strategy and implementation of DOE (planned experiment) and QFD (quality function deployment) in business. There are described about these methods. It deals with their use for a given problem. The last section provides a possible procedure in the enterprise.
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Production process optimization
Hejzlar, Aleš ; Vacek, Jan (referee) ; Fiala, Alois (advisor)
This diploma thesis deals with the production process optimization. The cutting operation and the lathe-turning issue is described in this thesis. In the practical part the production process is analyzed, the designed experiment (DOE) is suggested and evaluated. In the end of the practical part there is the evaluation of the machined material in the light of microstructure. On the basis of the partial findings the enclosures are done and the recommendations leading to the production optimization are suggested.
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Characterization of VTR-7000 deposition furnace
Petrová, Lenka ; Ulrych, Jan (referee) ; Semiconductor, Vlastimil Hanáček, ON (advisor)
Tato práce je zaměřena na problém nastavení CVD pece pro produkci ve výrobním závodu. Problém je, že přesná zařízení jako depoziční pece musíbýt pro produkci nastaveny až na místě, kde budou provozovány. Toho je možno docílit pomocí statistických nástrojů jako například DOE (design of experiment). Vstupní hodnoty procesu ovlivňují výstupy. Úkolem DOE je definovat, jakým způsobem. Z předchozího DOE provedeného v závodě COM1 vyplývají některá nastavení proměnných. Jiné proměnné musí být nastaveny dle předchozích zkušeností. Úkolem práce je seznámit čtenáře se základy depozice z plynné fáze a konceptem DOE. Následně je navržen vlastní experiment. Tento je vyhodnocen a výstupem práce je pak ideální nastavení reaktoru. Čtenáři bude též nepřímo představen proces DMAIC, který byl použit při samotném experimentu a vyhodnocování v ON Semiconductor, Rožnov pod Radhoštěm, CZ4 WFAB.
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