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Conditions of observation of electrode masses in environmental scanning electron microscope
Drnovský, Radek ; Michálek, Martin
When an electrochemical battery operates, oxides and sulphides are produced on the interface between the electrode mass and collector. This causes a short battery life and less efficiency. For the study of these phenomena the observation of the structure of the surface of the electrode mass in the ESEM was chosen. The electrode mass is operated in a liquid of an electrolyte. When the specimen is observed in the classic scanning electron microscope (SEM), its surface is enormously dried by the vacuum and its state does not correspond to the original state in the battery. Observation in ESEM allows the use of working pressures in the range from tens to thousands of Pa, and the drying of the specimen is suppressed. When the working conditions in the specimen chamber are changed, the quality of given images changes too. The aim of the experiment is to determine optimum conditions for the attainment of a good-quality image of the structure of the electrode mass surface in the ESEM.
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Hygiene Factors Issues of Noise, Dust and Vibrations in the Workplace Grinding Castings
STODOLOVSKÁ, Květa
My diploma work is focusing on the health problems of selected factors in the working enviroment of grinding the metal castings. There are high-risk factors, which are harmful to worker´s health, especially physical stress, noise, dust and vibrations, which are passed on hands. The employer is under the obligation to take precautions to carry on worker´s health, in consideration of exceed the health limits. The aim of this diploma work was setting the efficiency of precautions to health protection in work enviroment. The situation had been monitoring in a company in the South Bohemia over ten years. There were used results of factor´s precautions (noise, dust, vibrations) in work enviroment, where workers grind the metal castings by hand grinders. The monitoring ensemble was created by employess in a company, which makes the metal castings by hand grinders in its work enviroment. To data collecting were used the following methods: non-aligned observation, conversation with the chief of the company, studying of positive law and technical literature incl. test codes of the health institute (department Ceske Budejovice). The data of the test codes were processed by the secundary analysis and summarized to tables and graphs. Within qualitative analysis I determinated four research questions, which were answered gradually in my work: 1)Which precautions are carry out by employers to particular factors of employee´s health protection? 2)What is the factor´ s efficiency? 3)What impact do the precautions have on results of factor´s measuring? 4)Which precautions can I recommend on the grounds of the evalutation of the work enviroment? Both means of collective and individual protection belong to the precautions of worker´s health protection today. The technical, technologiacal and organisational precautions are included to collective protections. The individual precautions are focusing especially on employees and offer the substitute solutions. All precautions are specific to individual factors. I found out, that all precautions, which are used by the employers in work enviroment of metal casting, are effective. Especially we can talk about the precautions to protection of employee´s health against excessive dust (instalation of air ventilation with strong effect), which caused the exceed of dust concetration in work enviroment of grinding. Finally I can say, that this branch of metal casting has been connecting with certain high-risk factors all the time. Although all the protective precautions has been realized, the health limits given for noise, vibrations passed on hands and dust are still exceed. For this reason it´s very important to regularly inform the workers of high-risk factors, which they could meet in their work enviroment of cast grinding.
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Assessment of laboratory tests efficiency in case of exocrine pancreas function determination
Šubčíková, Lenka ; Martínková, Markéta (advisor) ; Milichovský, Jan (referee)
Chronic pancreatitis is complex disease with complicated diagnosis. Nowadays there are the diagnosis and classification of chronic pancreatitis primarily based on imaging methods. In this study the results of two indirect tests of pancreatic exocrine function with different arrangement were compared. The pancreatic fecal elastase 1 was determinate by immunoassay with monoclonal antibody, as a simple screening test. The dynamics and kinetics of pancreatic exocrine secretion was observed by a breath test with 13 C-labeled substrate. The group of four volunteers was monitored for six months and analyzed each month. The mutual variability of these tests and their correlation was studied. The patients' (suspected suffering by chronic pancreatitis) anonymous data for these tests created by the Institute of laboratory biochemistry and laboratory diagnostics between 1999-2012 were statistical processed. We found, that the indirect tests of pancreatic exocrine function and determination of pancreatic enzymes does not correlate. Both of these tests have the specific diagnostic value mainly for diagnosis of pancreatic exocrine insufficiency. 1
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Clustering and regression analysis of micro panel data
Sobíšek, Lukáš ; Pecáková, Iva (advisor) ; Komárek, Arnošt (referee) ; Brabec, Marek (referee)
The main purpose of panel studies is to analyze changes in values of studied variables over time. In micro panel research, a large number of elements are periodically observed within the relatively short time period of just a few years. Moreover, the number of repeated measurements is small. This dissertation deals with contemporary approaches to the regression and the clustering analysis of micro panel data. One of the approaches to the micro panel analysis is to use multivariate statistical models originally designed for crosssectional data and modify them in order to take into account the within-subject correlation. The thesis summarizes available tools for the regression analysis of micro panel data. The known and currently used linear mixed effects models for a normally distributed dependent variable are recapitulated. Besides that, new approaches for analysis of a response variable with other than normal distribution are presented. These approaches include the generalized marginal linear model, the generalized linear mixed effects model and the Bayesian modelling approach. In addition to describing the aforementioned models, the paper also includes a brief overview of their implementation in the R software. The difficulty with the regression models adjusted for micro panel data is the ambiguity of their parameters estimation. This thesis proposes a way to improve the estimations through the cluster analysis. For this reason, the thesis also contains a description of methods of the cluster analysis of micro panel data. Because supply of the methods is limited, the main goal of this paper is to devise its own two-step approach for clustering micro panel data. In the first step, the panel data are transformed into a static form using a set of proposed characteristics of dynamics. These characteristics represent different features of time course of the observed variables. In the second step, the elements are clustered by conventional spatial clustering techniques (agglomerative clustering and the C-means partitioning). The clustering is based on a dissimilarity matrix of the values of clustering variables calculated in the first step. Another goal of this paper is to find out whether the suggested procedure leads to an improvement in quality of the regression models for this type of data. By means of a simulation study, the procedure drafted herein is compared to the procedure applied in the kml package of the R software, as well as to the clustering characteristics proposed by Urso (2004). The simulation study demonstrated better results of the proposed combination of clustering variables as compared to the other combinations currently used. A corresponding script written in the R-language represents another benefit of this paper. It is available on the attached CD and it can be used for analyses of readers own micro panel data.
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Internal equity principle in the context of company strategy
Kopecký, Martin ; Nový, Ivan (advisor) ; Háša, Stanislav (referee) ; Blažek, Ladislav (referee)
The thesis deals with the scientific problem of the link between the strategic management and the compensation system using the principle of internal equity. The work is based on two pillars, namely the qualitative research and own proposed solution. The first part of the thesis describes the qualitative research and the possibilities and the synergistic effects of linking business strategy and compensation system. The qualitative research is performed as a multi-case study and investigates the phenomenon in the practice of three companies from various markets (the Czech Republic, Slovakia and Bosnia and Hercegovina) and industries (finance, IT/Telco and FMCG). The research tries to find answers to the four research questions: How does business strategy influence compensation process? How can compensation support the realization of a business strategy? How can business strategy be linked with a compensation system within the principle of internal equity? How can compensation reinforce the strategic function of the human resources management? The research is based on the study of theoretical sources as well as on practical fieldwork. The qualitative research itself uses qualitative research methods for data collection, such as observations, questionnaires, and document analysis. The population questioned was top managers, line managers and representatives of HR department. In total, 142 interviews were performed by a single person. The collected data were analyzed and the triangulation was applied. The findings were summarized and generalized into a final report that brings answers to the research questions above. The research brings valuable findings used in the second, design part of the thesis. The own proposed solution consists of two main models. The first one is a simplified scheme of the compensation system and the second one is a model of strategic segmentation of jobs. The first model could be used successfully in the business practice as well as in education. The second model of the strategic job segmentation brings answer to the question of synergistic linking of business strategy and the compensation system within the principle of internal equity. The model brings valuable findings and a foundation for further theoretical research and its further development. The model also brings practical solution to the design of related policies and processes in the strategic management of human resources. By the design of both proposed models the main objectives of the thesis were achieved.
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CRM System Optimization
Fučík, Ivan ; Mildeová, Stanislava (advisor)
This thesis is focused on CRM solutions in small and medium-sized organizations with respect to the quality of their customer relationship. The main goal of this work is to design an optimal CRM solution in the environment of real organization. To achieve this goal it is necessary to understand the theoretical basis of several topics, such as organizations and their relationship with customers, CRM systems, their features and trends. On the basis of these theoretical topics it is possible to analyze current CRM solution in the organization. From the data obtained by the methods of observation and controlled interview it was possible to prepare a design for optimal CRM solution. This optimal solution comes also from user and organization requirements. The optimal CRM solution saves time and costs associated with current CRM solution and replaces existing and ineffective CRM tools.
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ELECTRON BEAM REMELTING OF PLASMA SPRAYED ALUMINA COATINGS
Matějíček, Jiří ; Veverka, J. ; Čížek, J. ; Kouřil, J.
Plasma sprayed alumina coatings find numerous applications in various fields, where they enhance the properties of the base material. Examples include thermal barriers, wear resistance, electrical insulation, and diffusion and corrosion barriers. A typical structure of plasma sprayed coatings, containing a multitude of voids and imperfectly bonded interfaces, gives them unique properties - particularly low thermal conductivity, high strain tolerance, etc. However, for certain applications such as permeation barriers or wear resistance, these voids may be detrimental.\nThis paper reports on the first experiments with remelting of plasma sprayed alumina coatings by electron beam technology, with the purpose of densifying the coatings and thereby eliminating the voids. Throughout the study, several parameters of the e-beam device were varied - beam current, traverse velocity and number of passes. The treated coatings were observed by light and electron microscopy and the thickness, structure and surface morphology of the remelted layer were determined and correlated with the process parameters. Based on the first series of experiments, the e-beam settings leading to dense and smooth remelted layer of sufficient thickness were obtained. In this layer, a change of phase composition and a marked increase in hardness were observed.\n
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Characterization of FRET sensor
Datinská, Vladimíra ; Klepárník, Karel ; Belšánová, B. ; Minárik, M. ; Foret, František
In this study, we present characterization of sensor based on Fӧrster resonance energy\ntransfer (FRET). The sensor is composed of ssDNA chain attached to a laboratory\nsynthesized quantum dot (QD). A complementary chain of a sample is labeled by a\nluminescent dye. When the dsDNA hybrid is formed, the energy from the QD (donor)\nis transferred to the dye (acceptor) and FRET is observed as a decrease of QD\nluminescence emission intensity and an increase of dye luminescence emission\nintensity.
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Comparison of cytokine production by leukocytes from newborns of healthy and allergic mothers
Dusilová, Adéla ; Hrdý, Jiří (advisor) ; Janatková, Ivana (referee)
The increasing incidence of children suffering from allergic diseases could be caused by sensitization of immature immune system during the intrauterine development. Several important scientific papers have demonstrated the ability of cord blood cells to respond by elevated proliferation activity after stimulation by common allergens. Following these findings, present study follows the production of cytokines which play a role in the pro- and anti-allergenic tuning of the immune system. Umbilical cord blood cells were stimulated with polyclonal activators (phytohaemagglutinin) and common allergens (ovalbumin, timothy grass, birch, mite). Subsequently, cytokine production was monitored using selected methods that reflect different stages of cell activation - at the level of mRNA by quantitative real time PCR (qRT-PCR), by flow cytometry detection of the presence of intracellular cytokines in different cell subpopulations and by ELISA measurement of cytokines in CBMC culture supernatants. The results obtained point to a very weak ability of these common allergens (timothy grass, birch, mite, ovalbumin) to stimulate CBMC to produce cytokines observed by all of these methodological procedures. Although we did not observe significant differences in CBMC cytokine production (IL-2, IL-4, IL-10, IL-12,...
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Sorption and Stabilization of Metals/Mettalloids by Innovative Synthesized Sorbent Amochar.
Ouředníček, P. ; Trakal, L. ; Komárek, M. ; Pohořelý, Michael
Remediation of contaminated soil which is based on stabilization and immobilization of potential\nhazardous substance by sorption materials has been studied intensively nowadays. Biochar – activated organic carbon belongs to this group of stabilizing agents which can adsorb wide range of contaminants, including metals/metalloids. Surface area of the biochars is quite large in general and functional groups (e.g. COO–) can form chelates or alkaline elements on the surface, which is represented by cation exchange capacity. Altogether with the high pH values (7.00 – 10.00), biochars are quite effective sorbents and can adsorb metals/metalloids from the solution (ground water), especially in acidic soils (in the environments affected by intensive mining activities). Sorption\neffectiveness can be increased (especially for As (V) or Cr (VI) sorption) by modification of biochar by various types of secondary oxides. Innovative sorbent AMOchar (AMO + biochar) has been synthesized currently. The product was prepared by adding of biochar to the reaction solution during amorphous manganese oxide (AMO) synthesis. The AMOchar was formed mainly by Mn-oxalates which had coated surface of the pristine biochar. AMOchar composite was able to remove significantly higher amounts of various metal(loid)s from the solution despite the rather high pH of the material. Sorption effectiveness was high not only in case of Pb (II) sorption (almost 99%), and Cd(II) (51.2%), but also a very high amount of As(V), 91.4%. Additionally, both AMOchar composite was able to reduce Mn leaching. This can avoid potential post-contamination caused by the dissolution of less stable Mn-oxalates as observed in the pure AMO.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_22316111113040 - PDF
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