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STRAIN ENGINEERING OF THE ELECTRONIC STRUCTURE OF 2D MATERIALS
del Corro, Elena ; Peňa-Alvarez, M. ; Morales-García, A. ; Bouša, Milan ; Řáhová, Jaroslava ; Kavan, Ladislav ; Kalbáč, Martin ; Frank, Otakar
The research on graphene has attracted much attention since its first successful preparation in 2004. It possesses many unique properties, such as an extreme stiffness and strength, high electron mobility, ballistic transport even at room temperature, superior thermal conductivity and many others. The affection for graphene was followed swiftly by a keen interest in other two dimensional materials like transition metal dichalcogenides. As has been predicted and in part proven experimentally, the electronic properties of these materials can be modified by various means. The most common ones include covalent or non-covalent chemistry, electrochemical, gate or atomic doping, or quantum confinement. None of these methods has proven universal enough in terms of the devices' characteristics or scalability. However, another approach is known mechanical strain/stress, but experiments in that direction are scarce, in spite of their high promises.\nThe primary challenge consists in the understanding of the mechanical properties of 2D materials and in the ability to quantify the lattice deformation. Several techniques can be then used to apply strain to the specimens and thus to induce changes in their electronic structure. We will review their basic concepts and some of the examples so far documented experimentally and/or theoretically.
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Awareness of women about nutrition problems such as breast cancer prevention
STAŇKOVÁ, Denisa
This thesis focuses on the awareness of women of the nutrition issue as the prevention of breast cancer. The aim of this thesis is to find out whether the women have enough information about nutrition and life style as the prevention of breast carcinoma, where they look for information, if they are interested in this issue and whether they consume food that could work as the prevention. Another goal is to detect possible differences in the attitude to the prevention between women without the potential risk and women with the increased risk, i.e. women over 45. Research questions were determined as follows: "What is the knowledge of women about the issues of nutrition as the prevention of breast cancer?", "What is the proportion of the food that has preventive effect on the rise of breast carcinoma and, on the contrary, the food that supports the tumour growth in the eating habits of women?", "Where do women get information on this issue?", "What is the difference in awareness and consumption of food between women without the potential risk and women with the increased risk, i.e. over 45. The thesis is divided into two parts, a theoretical and a practical one. In the theoretical part I focus on the breast anatomy, basic information on breast cancer and risk factors that are divided into influenceble ones and non-influenceble ones. In the most extensive part of my thesis focuses on the influenceble factors, that is nutrition and life style. I focus especially on nutriments, food and other life style factors that are most connected with breast cancer and have antitumour effects or, conversely, support the tumour growth. The practical part was made by means of a questionnaire which I placed on the Internet and handed out in the waiting room at the general practitioner. The questionnaire was anonymous with 34 questions of a closed and semi-enclosed type. Questions concerned nutrition and life style in relation to the risk of breast cancer and were devised to answer previously defined research questions. The questionnaire survey took place in January and February 2013. I acquired 105 filled in questionnaires from which I randomly chose 86 to obtain two numerously equal groups of women without the potential risk and with the increased risk, i.e. over 45. The result of the research part is that women do not have much information on the life style in connection with the breast cancer. Some respondents, while selecting food with preventive effect, were only guessing and often also marked food which was not related to the breast carcinoma at all. About one third of the respondents even believe that nutrition and other factors are not related to this disease at all. One third of the respondents also stated that they had no interest in learning more information on this issue. Women that have some information usually get it from the magazines and from the Internet. In terms of eating habits, the food of most respondents does not reach the needed quantity to have preventive effects. On the other hand, the food and drinks that support tumour growth do not occur on the menu of the respondents very often. While comparing answers of the women younger 45 and the older group of respondents, it was found out that the younger respondents showed greater unawareness of this issue. No significant differences were recorded in other questions. The results of the survey are graphically processed and evaluated in the final part of this thesis. I suppose this thesis is the contribution to clarifying the current situation of this issue. I believe that the topic of my thesis is up-to-date and that I managed to summarize the most significant information regarding this topic and fulfil the aims I set down. I would be very glad if my work led to the contemplation of this issue and subsequently to a more extensive propagation of the breast cancer prevention.
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Intuition in creative process of animation movie
Nováčková, Jana Kristýna ; DĚCKÁ, Eliška (advisor) ; ČIHAŘOVÁ, Libuše (referee)
This work deals with the relation of emotions to contemporary experimental animation. It engages in the emotional experience of a viewer to non-narrative film storytelling and its means of expression.
At the same time, it examines what the creative processes and attitudes of filmmakers towards emotions in experimental animation are. Analysis of the questionnaires also reveals whether the creator counts on the viewer's specific interpretation of the film.
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Neural Networks Between Integer and Rational Weights
Šíma, Jiří
The analysis of the computational power of neural networks with the weight parameters between integer and rational numbers is refined. We study an intermediate model of binary-state neural networks with integer weights, corresponding to finite automata, which is extended with an extra analog unit with rational weights, as already two additional analog units allow for Turing universality. We characterize the languages that are accepted by this model in terms of so-called cut languages which are combined in a certain way by usual string operations. We employ this characterization for proving that the languages accepted by neural networks with an analog unit are context-sensitive and we present an explicit example of such non-context-free languages. In addition, we formulate a sufficient condition when these networks accept only regular languages in terms of quasi-periodicity of parameters derived from their weights.
Fulltext: content.csg -  PDF
Plný tet: v1237-16 - PDF
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Alternative methods of leading childbirth
PAPAI, Daria Kristina
The topic of my bachelor thesis is "Alternative methods of child delivery". The theoretical part describes the physiological delivery its particular phases and their progression. In addition, I aim to explain what the term alternative birth means, and what it includes. The various alternative positions are described, which can be used to facilitate childbirth, as well as their appropriate use during the particular delivery phases. The theoretical part is concluded by descriptions of pain relief methods, including the description of both pharmacological and non-pharmacological methods. The second part of the thesis is a practical part, summarizes the results of an evaluation research. The aim was to explore the most used alternative methods and to identify the views and experiences of women with alternative methods and aids used during delivery in selected hospitals. Furthermore, the aim was to describe the regions of the Czech Republic in terms of the use of alternative aids and procedures. The hypotheses were formulated based on previous experiences and personal opinions of the author of the thesis. The research sample consisted of women after a spontaneous child delivery in the České Budějovice Hospital and in the Znojmo Hospital. The research was conducted in the form of an anonymous questionnaire survey, using a non-standardized questionnaires. The results of the survey were compiled in tables and the chi-square test was applied as a method for statistical processing and verifying the hypotheses.
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Effect of snowpack on runoff generation during rain on snow event.
Juras, Roman ; Máca, Petr (advisor) ; Ladislav , Ladislav (referee)
During a winter season, when snow covers the watershed, the frequency of rain-on-snow (ROS) events is still raising. ROS can cause severe natural hazards like floods or wet avalanches. Prediction of ROS effects is linked to better understanding of snowpack runoff dynamics and its composition. Deploying rainfall simulation together with hydrological tracers was tested as a convenient tool for this purpose. Overall 18 sprinkling experiments were conducted on snow featuring different initial conditions in mountainous regions over middle and western Europe.
Dye tracer brilliant blue (FCF) was used for flow regime determination, because it enables to visualise preferential paths and layers interface. Snowpack runoff composition was assessed by hydrograph separation method, which provided appropriate results with acceptable uncertainty. It was not possible to use concurrently these two techniques because of technical reasons, however it would extend our gained knowledge. Snowmelt water amount in the snowpack runoff was estimated by energy balance (EB) equation, which is very efficient but quality inputs demanding. This was also the reason, why EB was deployed within only single experiment.
Timing of snowpack runoff onset decrease mainly with the rain intensity. Initial snowpack properties like bulk density or wetness are less important for time of runoff generation compared to the rain intensity. On the other het when same rain intensity was applied, non-ripe snowpack featuring less bulk density created runoff faster than the ripe snowpack featuring higher bulk density. Snowpack runoff magnitude mainly depends on the snowpack initial saturation. Ripe snowpack with higher saturation enabled to generate higher cumulative runoff where contributed by max 50 %. In contrary, rainwater travelled through the non-ripe snowpack relatively fast and contributed runoff by approx. 80 %.
Runoff prediction was tested by deploying Richards equation included in SNOWPACK model. The model was modified using a dual-domain approach to better simulate snowpack runoff under preferential flow conditions. Presented approach demonstrated an improvement in all simulated aspects compared to the more traditional method when only matrix flow is considered.
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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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