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Global value chains in the coffee industry focused on Vietnam
Klumparová, Adéla ; Vlčková, Jana (advisor) ; Hnát, Pavel (referee)
Aim of this diploma thesis is to describe functioning of global coffee value chains and this knowledge then apply to the coffee industry in Vietnam which serves as a case study. The introductory chapter focuses firstly on institutional background of value chains, processes and management processes used in the agricultural industry. The thesis also contains analysis of global coffee value chain, including the identification of entities engaged in the chain and their contribution to the creation of added value. Next chapter describes the development of the world coffee market and production of the world's major producers and exporters of coffee. The thesis also deals with the topic of economic and social sustainability and the impact of global value chains on the environment. Final part of the thesis concentrates on the position of the coffee industry in Vietnam, its structure and development over the past 40 years. Attention is paid also to a problematic position of small growers or to the opportunities of the development of the local coffee industry.
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Optimalization of material flow in automotive industry
Kolář, Tomáš ; Jirsák, Petr (advisor) ; Vinš, Marek (referee)
This master thesis is focussed on optimalization of material flow in an automotive company. First part introduce theoretical background. Automotive industry and its actual trends on global markets. Follows short introduction of the company where project of this thesis was executed. Main theoretical part describes concept of lean management, its tools in practical examples, but it is also focussed on philosophical approach to the work and mindset of the company. Follows the aplication part based on theoretical background. The whole project of this master thesis is focussed on specific area called PC store. At first this area is showed in context of overall material flow. Shortly there are introduced processes and areas where full material packaging flows. Follows deeper analysis and optimalization of PC store itself. There are three approaches of stock and lead time reduction applied. Last part shows the comparison of initial and future state including performed changes.
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Modelling, parameter estimation, optimisation and control of transport and reaction processes in bioreactors.
ŠTUMBAUER, Václav
With the significant potential of microalgae as a major biofuel source of the future, a considerable scientific attention is attracted towards the field of biotechnology and bioprocess engineering. Nevertheless the current photobioreactor (PBR) design methods are still too empirical. With this work I would like to promote the idea of designing a production system, such as a PBR, completely \emph{in silico}, thus allowing for the in silico optimization and optimal control determination. The thesis deals with the PBR modeling and simulation. It addresses two crucial issues in the current state-of-the-art PBR modeling. The first issue relevant to the deficiency of the currently available models - the incorrect or insufficient treatment of either the transport process modeling, the reaction modeling or the coupling between these two models. A correct treatment of both the transport and the reaction phenomena is proposed in the thesis - in the form of a unified modeling framework consisting of three interconnected parts - (i) the state system, (ii) the fluid-dynamic model and (iii) optimal control determination. The proposed model structure allows prediction of the PBR performance with respect to the modelled PBR size, geometry, operating conditions or a particular microalgae strain. The proposed unified modeling approach is applied to the case of the Couette-Taylor photobioreactor (CTBR) where it is used for the optimal control solution. The PBR represents a complex multiscale problem and especially in the case of the production scale systems, the associated computational costs are paramount. This is the second crucial issue addressed in the thesis. With respect to the computational complexity, the fluid dynamics simulation is the most costly part of the PBR simulation. To model the fluid flow with the classical CFD (Computational Fluid Dynamics) methods inside a production scale PBR leads to an enormous grid size. This usually requires a parallel implementation of the solver but in the parallelization of the classical methods lies another relevant issue - that of the amount of data the individual nodes must interchange with each other. The thesis addresses the performance relevant issues by proposing and evaluation alternative approaches to the fluid flow simulation. These approaches are more suitable to the parallel implementation than the classical methods because of their rather local character in comparison to the classical methods - namely the Lattice Boltzmann Method (LBM) for fluid flow, which is the primary focus of the thesis in this regard and alternatively also the discrete random walk based method (DRW). As the outcome of the thesis I have developed and validated a new Lagrangian general modeling approach to the transport and reaction processes in PBR - a framework based on the Lattice Boltzmann method (LBM) and the model of the Photosynthetic Factory (PSF) that models correctly the transport and reaction processes and their coupling. Further I have implemented a software prototype based on the proposed modeling approach and validated this prototype on the case of the Coutte-Taylor PBR. I have also demonstrated that the modeling approach has a significant potential from the computational costs point of view by implementing and validating the software prototype on the parallel architecture of CUDA (Compute Unified Device Architecture). The current parallel implementation is approximately 20 times faster than the unparallized one and decreases thus significantly the iteration cycle of the PBR design process.
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Pervaporation of Methanol Water Mixtures by PERVAPTM Asymmetric Membranes.
Izák, Pavel ; Kačírková, Marie
The report summarizes the results of experimental testing of pervaporative separation of methanol from methanol-water binary mixture at 35°C. For the separation were chosen the Sulzer´s PERVAPTM membranes. The concentration of methanol was 6.5 wt.% in water, and pervaporation was performed in vacuum mode. Membranes displayed separation properties suitable for industrial separation of methanol from water mixtures.
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Noise, Transport and Structural Properties of High Energy Radiation Detectors Based on CdTe
Šik, Ondřej ; Lazar, Josef (referee) ; Navrátil, Vladislav (referee) ; Grmela, Lubomír (advisor)
Poptávka ze strany vesmírného výzkumu, zdravotnictví a bezpečnostního průmyslu způsobila v posledních letech zvýšený zájem o vývoj materiálů pro detekci a zobrazování vysokoenergetického záření. CdTe a jeho slitina CdZnTe. jsou polovodiče umožnují detekci záření o energiích v rozsahu 10 keV až 500 keV. Šířka zakázaného pásma u CdTe / CdZnTe je 1.46 -1.6 eV, což umožňuje produkci krystalů o vysoké rezistivitě (10^10-10^11 cm), která je dostačující pro použití CdTe / CdZnTe při pokojové teplotě. V mé práci byly zkoumány detektory CdTe/CdZnTe v různých stádiích jejich poruchovosti. Byly použity velmi kvalitní spektroskopické detektory, materiál s nižší rezistivitou a výraznou polarizací, detektory s asymetrií elektrických parametrů kontaktů a teplotně degenerované vzorky. Z výsledků analýzy nízkofrekvenčního šumu je patrný obecný závěr, že zvýšená koncentrace defektů způsobí změnu povahy původně monotónního spektra typu 1/f na spektrum s výrazným vlivem generačně-rekombinačních procesů. Další výrazná vlastnost degenerovaných detektorů a detektorů nižší kvality je nárůst spektrální hustoty šumu typu 1/f se vzrůstajícím napájecím napětí se směrnicí výrazně vyšší než 2. Strukturální a chemické analýzy poukázaly, že teplotní generace detektorů způsobuje difuzi kovu použitého při kontaktování a stopových prvků hlouběji do objemu krystalu. Část mé práce je věnována modifikaci povrchu svazkem argonových iontů a jejímu vlivu na chemické složení a morfologii povrchu.
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Analysis of business and entrepreneurship sector policy in the town Písek
KOSTOHRYZOVÁ, Andrea
The aim of my thesis is to analyse business and entrepreneurship sector of the town Písek and positive attitude of the local municipality towards private business sector operating on the largest industrial zone in South Bohemia. Theoretical part concentrates on description and explanation of the basic terms and relations dealing with the topic of regional development. Afterwards, I focus on description of public and private sectors and possibilities of providing financial subsidies from both national and EU funds. The first section of practical part concentrates on detailed description of the region Písek from various viewpoints social, demographic, economic, industry sectors and competitiveness. Furthermore, I describe and analyse business and entrepreneurship conditions within the industrial zone lying on the edge of the northern part of the town Písek focusing on the past, present and future. I also describe clusters and evaluate success rate and effectiveness of the town Písek in obtaining financial subsidies from both national and EU funds. The last part uses the findings to compare the industrial zone in Písek with a similar industrial zone in Vodňany. Finally, I summarise and evaluate all findings. I outline the possibilities of further development of the industrial zone Písek and ways to obtain financial subsidies for development of business and entrepreneurship sector in the town Písek from accessible European funds.
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The effect of pyrethroid based pesticides on fish
RICHTEROVÁ, Zuzana
Pyrethroids are ones of the most used pesticides worldwides. The widespread use and high stability of pyrethroids lead to the assumption of that their occurrence in the environment could be quite frequent. They can reach water ecosystem as pollutants. Residues of pyrethroids are not only detected in the water column, but also in sediments and in fish tissues. The first study was devoted to the product Nexide containing 60 g.l-1 of active substance gamma-cyhalothrin. Tested Nexide concentrations were 5, 25, 50, 100, and 250 µg.l-1. Early life stage test was used.Common carp (Cyprinus carpio) was tested. There were significant mortalities in all concentrations except the lowest concentration during the trial. The lowest concentration tested 5 µg.l-1 only caused a slightly increased mortality. This lowest concentration influenced the growth in length and weight negatively, decelerated ontogenetic development, and made the body surface of the individuals darker. Histopathology of individuals from this concentration revealed dystrophy in liver. Examination of kidney, intestine and gills did not show significant histopathological differences compared with control. The evaluation of selected parameters of oxidative stress demonstrated a significantly higher activity of detoxification enzyme glutathione-S.transferase (GST) and a significantly lower activity of defensive enzyme glutathione peroxidase (GPx) compared with the control group. The other examined parameters of oxidative stress such as catalase (CAT), glutation reductase (GR), and lipid peroxidation determined by using the thiobarbituric acid-reactive substances (TBARs) were comparable to the control group. Changes in oxidative stress parameters suggest that exposure of the organism to the product Nexide in the given concentration leads to dysbalance of defensive enzymes. The second study was devoted to the product Cyperkill 25 EC containing 250 g.l-1. Tested Cyperkill 25 EC concentrations were 7.2, 36, 72, 144, and 360 µg.l-1. The procedure of the trial was the same as the preceded one. There were 100% mortalities in all concentrations except the lowest concentration during the trial. The lowest tested concentration 7.2 µg.l-1 allowed 90% of individuals to stay alive till the end of experiment. The lowest concentration influenced the growth in length and weight negatively and decelerated ontogenetic development compared with the control. Any individual exposed to this concentration did not reach juvenile stage until the end of the trial. Dark pigmentation was visible in 68% of these exposed individuals on the last day. Similar darkening was visible in individuals from higher concentrations shortly before death too. Histological examination did not revealed significant changes in intestine, liver, kidney, and gills compared with the control group. Evaluation of selected parameters of oxidative stress demonstrated significantly lower activities of GST, GR, and GPx. Activities of CAT and TBARS were comparable with the control group. Changes in oxidative stress parameters suggest that exposure of the organism to the product Cyperkill 25 EC in the given concentration could induce oxidative stress and interfere with the activities of antioxidant enzymes. The presented thesis summarises actual data about pyrethroids and their influence on fish. The demonstrated effects confirm high susceptibility of early developmental stages of fish to tested pesticides. When interpreting the results, we have to take into account the fact that studies showed this risk even on single pyrethroid substances. But water organisms are exposed to many other more or less toxic products and substances in a real environment. These xenobiotics could react with each other and their mixture could even potentiate negative effects. The performed studies also clearly show the significant differences in the sensitivity of embryonic and embryolarval tests.
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Feeding dogs the natural way
Beranová, Daniela ; Rozinek, Jiří (advisor) ; Libuše, Libuše (referee)
The bachelor thesis has the character of literary research. Focusing on feeding dogs the natural way. It is divided into several chapters.
The first chapter describes the digestive tract of the dog, its parts and operations which it provides. First described digestive system overall, and its importance for the body of the dog. The first part of the digestive system is the head portion, which include the mouth, including teeth, and pharynx. In the pharynx the digestive crosses paths with breathing. Epiglottis separates the head portion from the front intestine, which starts and continues through the esophagus into the stomach. It is connected to the small intestine, which parts are duodenum, jejunum and ileum. Small intestine enters the large intestine. It has three distinct parts: cecum, colon and rectum. Rectum narrows the anal canal, which ends anus. Further additives are described intestine organs and their functions. They are the liver and pancreas.
The second chapter focuses on the fact that the dog is a carnivore. Briefly summarized the emergence of dog domestication of the wolf and his digestive system, since it is still very similar. Changing digestion is a process that requires several hundred years. This section also describes what nutrients are important in the food contained a brief description. Another important part of the food is fresh water.
The third chapter is a division of commercially produced feed. They are divided according to water content and the method of preservation, according to the quality of raw materials and by ages, sizes and breeds workload. The next section summarizes the book by Dr. Hans-Ulrich Grimm. He is a journalist and author of several books that reveal the truth about industrial foods and certain brands in the industry.
The main part deals with the natural food for the dog. Is it a combination of meat, vegetables, fruits and sometimes other supplements, such as dairy products, cereals, herbs and much more. This chapter summarizes the advantages and disadvantages of feeding a natural food.
Finally, the work distinguishes the difference benefit the dog fed first industrially produced feed, then the natural food.
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Atomic absorption spectrometry
Dočekal, Bohumil
Atomic absorption spectrometry is one of the most useful methods applied in trace element analysis, particularly due to high sensitivity and due to relatively low investment and operational costs. This method enables to determine up to 60 elements, metals and metalloids, within a wide concentration range from ug.l-1 to tenth of g.l-1. The contribution deals with fundamental principles of the method and instrumentation, including light sources, optical systems and modern background correction techniques. It systematically describes flame and flameless atomization and sample introduction techniques. Basic analytical parameters of the method, detection power, sensitivity, dynamic working range, standardization approaches, methodology, quality control and assurance are also discussed.
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