|
The Pump with a Diffuser with Stochastic Blades (Runner and Diffuser)
Dobšáková, Lenka ; Melichar, Jan (referee) ; Veselý, Jindřich (referee) ; Haluza, Miloslav (advisor)
This doctoral thesis studies the non-uniform blade cascade for centrifugal pumps. Influence of non-uniform blade cascade is investigated on the impeller and diffuser. A non-uniform blading impeller of pumps in this doctoral thesis was examined in terms of influence on efficiency characteristic. The idea of using non-uniform blading is to obtain a flat efficiency characteristic. Then the centrifugal pump could be used on larger scale of power with achieving a sufficiently high efficiency. The work is based on experimental measurements and numerical simulations of non-uniform hydraulic pump components. Non-uniform impeller and the diffuser were newly designed for this research. A new measuring track of small submersible pumps was needed to design and build for measurements. Different pump combinations with conventional hydraulics on one working point and hydraulics with non-uniform were measured. All measurements were evaluated and characteristics of efficiency, head and power were obtained for each measured combination. Some of pump combinations (which were measured in experiment) were numerically simulated by program Ansys Fluent. Data needed to evaluate the characteristic of efficiency and specific energy were collected from each numerical simulation. A theoretical consideration concerns the influence of non-uniform blade cascade applied on diffuser. The suggestion how to decrease hydraulic losses in canals was done. The theoretical consideration how to make a flat efficiency characteristic was made.
|
|
(Arbo)viruses in high European Arctic
ELSTEROVÁ, Jana
Since an ongoing climate change covers strongly the polar areas. Higher temperatures and related climate parameters bring the emergence of new parasites and their pathogens to higher latitudes. This may influence zoonotic diseases including arthropod-transmitted diseases. The tick species Ixodes uriae, parasitizing seabirds in the Arctic, may transmit many pathogens including various arboviruses, Borrelia spirochetes and Babesia apicomplexans. In the study we diagnosed 89 individuals of seabird tick Ixodes uriae and searched for arthropod-borne viruses from the genera Flavivirus, Alphavirus, Orthobunyavirus, Phlebovirus and Orbivirus using genus-specific primers. Moreover we searched for presence of Borrelia spp. and Babesia spp. DNA in the ticks. All samples were negative after PCR amplification for all tested pathogens. The result signalizes that tested pathogens might not be present in such high latitudes of European Arctic. Though, the possibility of introduction of these pathogens may be observable in near future due to quick changing of the Arctic ecosystem with the rising of migration of vertebrate hosts including humans to the polar areas. It is though important to continue to study potential presence of pathogens in polar areas. We are working on increase of the number of tick samples to confirm the presence or absence of the tick-borne pathogens in the European Arctic.
|
|
Právní a zdravotně sociální aspekty činnosti OSPOD jako ustanovených opatrovníků v zámu nezletilých dětí
BORSKÁ, Jana
The Czech Republic as a signatory of the Convention on the Rights of the Child has vested the practice of state administration in the field of care for minor children to municipalities with extended powers, where the protection of the rights and legitimate interests of minor children is safeguarded by state authorities of social and legal protection of children (ASLPC hereinafter). These authorities are incorporated to the extent laid down by the Act on Social and Legal Protection of Children (Act No 359/1999 Coll., as amended). The position and roles of ASLPC and their competence and jurisdiction are also regulated by the same act. The position of workers of these authorities and its legal embodiment is equally important. Regarding professionality, there are high demands on these workers. In the Czech Republic, significant changes in legislature have been made over the past three years. These amendments have led to the strengthening of the rights of minor children and to the establishing of new tools for their protection. In connection with the adoption of new substantive regulation of family law, which is now exhaustively dealt with by the Act No 89/2012 Coll., the Civil Code, new procedural rules have been established regarding protection of rights of minor children. Such procedural legislation includes (apart from the long-existent Act No. 99/1963, the Code of Civil Procedure) the Act No 292/2013 Coll., on Special Civil Proceedings. The decision-making regarding minor children has been vested mainly by the state into the competence of courts. The courts appoint the locally relevant ASLPC as a guardian who then represents the interests of minor children. The purpose, interwoven with and derived from the first one, was to explore the opinions of selected social workers of ASLPC and of district court judges regarding the defined problems occurring during the work of ASLPCs and courts while protecting the interests of minor children. These particularly include: the use of the tool of precautionary measure; problems of different territorial jurisdiction of courts and ASLPCs; processing of complaints regarding bias in various phases of the proceedings; professional training of workers of ASLPC It is evident from the proposals of both judges and ASLPC workers that it is necessary to unify territorial jurisdiction. The courts are suggesting the priority criterion of the address where the child mainly resides. ASLPC workers suggest the official permanent residence as the prime criterion. Bias causes problems in all phases of proceedings. It is obvious that courts take differing approaches towards the solution of this problem (some courts solve the problem of bias complaints filed by the parties while other courts do not) and for ASLPC workers it is difficult to assess how to act when such complaint is raised against them. The training of ASLPC workers - workers are obliged to educate themselves and their employer is obliged to finance such training. Not all ASLPCs are able to provide training in the required extent - due to financial reasons (the average costs of education of one employee pose from 9,169 to 13,400 CZK annually and they cover approximately 6 days of training). The heavy work-load caused by insufficient numbers of ASLPC employees prevents them from completing such compulsory training. As part of the examination of the "participation of a collision guardian in court proceedings" it has been found out that irregular participation of the worker in the proceedings (absence from participation in appeals proceedings); incomplete reports (directed to courts) from surveys in families. Based on comprehensive examination of the problems of territorial jurisdiction, it was recommended that requests are independently recorded and financial compensation is provided for ASLPCs who are requested to represent minors in front of courts, to draft proposals for precautionary measures.
|
|
Is genetic diversity congruent with morphological diversity across the distributional range of the Melampyrum subalpinum group (Orobanchaceae)?
CHLUMSKÝ, Jan
Allozymes were used to assess the genetic structure of 27 populations of Melampyrum subalpinum group and an artificial pollination experiment was carried out to examine the possibility of autogamy. Genetic variation was generally congruent with the known morphological variation of the group. The results corresponded with the central-marginal concept. Allelic enrichment due to hybridization with M. nemorosum was observed in some Austrian populations. Czech and Slovak populations do not differ from Austrian populations. The high inbreeding coefficient and the pollination experiment do not contradict the possibility of autogamy.
|
|
Adolescent overweight and obesity
JINDROVÁ, Kateřina
My bachelor´s thesis deal with obesity of adolescents and problems with overweight. These problems are described in details, and after that divided into specific parts. The main goal of my bachelor´s thesis is to chart problems with obesity and overweight in age group from 15 to 18 (adolescents) and primary describe their eating habits and physical activity. Theoretical part is focused on occurrence of overweight and obesity in the Czech Republic and in the world, causes of its origin, risk factors, classification and diagnosis, types, therapy and prevention. This bachelor´s work dealing with rational diet, describing basic principles of healthy catering and explaining right or wrong foodstuffs. I point mainly on prevention of overweight and obesity by healthy eating and physical activity. Methodical part is processed thanks to quantitative research. Data were gained by questionnaires, which were given to high school students (1st - 3rd grade). The research group contains 150 respondents from different schools in České Budějovice and close neighborhood. Final results are written down primary in graphs with commentary and data charts. In case of right use of qualitative research, there were determined two hypotheses. First hypothesis: Overweight and obesity is more occurred at adolescents with wrong eating habits. Second hypothesis: Overweight and obesity is more occurred at adolescents with low physical activity. For developing exploratory part, there was used quantitative research, which was provided by questionnaires given to students of age from 15 to 18. Entire data were processed by the use of program Microsoft Excel, and its calculations and functions. The answers of respondents were registered into database, and, by using specific excel functions, I was able to report data in determined categories. The research was mainly concentrated on physical activity and eating habits. Final results are put into well-arranged graphs, which are always enriched by comments, eventually completed by data tables, and, subsequently, statistically evaluated. In results, there might be seen two main differences between adolescents with standard weight and adolescents with overweight or obesity problems. One of those is irregularity in eating and wrong eating habits; big difference is also proved in physical activity. Adolescents with obesity or overweight have often irregular food intake, they drink a lot of high caloric beverages such as Coca-Cola, Sprite, Fanta etc., deficient income of fruit, vegetables, legumes, fish, or low physical activity. Only few of obese adolescents is different, because their problem is caused genetically. Adolescents with standard weight eat more regularly, but there are also some special cases, who have similarly wrong eating habits as obese people; however, all of these adolescents have one typical quality regular physical activity. Both hypotheses are confirmed. The results show that obesity is mainly caused by genetic predispositions, but these factors can be positively affected by periodic physical activity or appropriate eating habits. At the end of the thesis, it should be mentioned that it is necessary to be focused on right eating habits and regular physical from the very young age, when the basic customs and habits are assumed. That should include parents' action around their children, as they are usually the first example and they have the biggest influence.It is important to develop knowledge about all kinds of prevention, which are in most cases major in defending against formation of overweight and obesity.
|
| |
|
Characteristics of the working behavior of Czechs and Ukrainians
BYKOVA, Sofia
The aim of this work is to create a transparent and comparable characteristics of the work behavior phenomenon within the cultures of those states - what is common and what is different between them, or maybe incompatible .It is supposed to have some analysis of possible conflicts and their connection with the mentality. The primary reason of this aim choosing is the specialty I study. My work contains information that could be interesting and useful not only for me and my future job, but also for managers and other employees. Overview of examined issues contains specific points, such as the fundamentals of economic psychology and behavioral economics (symbiosis of psychological and economic opinion on motivation and rationality of individuals), theories of motivation and reaction to different occurrence, characteristic of the term "mentality", general points about the human impact of the world economy. For realizing the goals of my work the following hypotheses have been proposed - Czech and Ukrainian mentality have significant differences, though these cultures are close. - Ukrainian and Czech employees are able to work effectively in a team and find a "common language" in the workplace. The difference in mentality does not obstruct on it. - Employers could be interested in the Ukrainian employees taking into account their high concernment and motivation. All three of the hypotheses were confirmed by observed data and comparison of mentality characteristics. Czechs are often tolerant to other cultures, moreover Ukrainian culture is not much different and does not create difficulties in the working relationship. Based on the fact that the chosen company has no conflicts associated with work behavior and differences in mentality, it's hard to define my contribution to this organization work.
|
|
Matematická analýza regularizovaného modelu viskoelastické nenewtonovské tekutiny
Šalom, Pavel ; Pokorný, Milan (advisor) ; Bulíček, Miroslav (referee)
In this thesis we provide an existence result for a regularized model of viscoelastic non- newtonian fluid. We consider incompressible fluid with shear rate dependent viscosity and with Cauchy stress tensor capable to describe stress relaxation. An elastic part of the Cauchy stress tensor is governed by Oldroyd-type differential equation. In particular, we are interested in fluids with strong shear thinning effect. We prove that if the viscosity function µ (D) is such that tensor µ (D) D is p-coercive, monotone and has (p − 1)-growth for p > 6 5 and some other additional assumptions are satisfied, then there exists a solution to the system of PDEs describing the flow in a bounded domain. The proof is not simple because the convective term is not integrable with a high power. The problem is solved using Lipschitz truncation method for evolution PDEs. 1
|
|
Distribution management in a large company (warehouse)
MICHALOVÁ, Jana
Distribution management in a large company. This Master´s Thesis examines the company Fruko-Schulz, s. r. o. This company has been making spirits. The goal is to map out the information and material flows toward the warehouse and from the warehouse. Subsequently, to analyze the current state of the company. Based on the information propose measures for improvement. In own work is described in detail and enterprise activities in a company. After ideas are designed to change. These proposals relate to distribution to the end customer through the gastronomical exhibitions and fairs. Other proposals are aimed at end users in the Russian market. Ideas for packaging or new products are designed, but is backed that do not make sense. Company Fruko-Schulz, s. r. o. sas a long tradition and reputation. But that's not enough, the competition is great and it isalso at a high level. The idea to focus on the Russian market is very good and there is great potential.
|
|
Doped DLC coatings for biomedical applications
Písařík, Petr
Nowadays there are materials having excellent properties for use in medicine (Diamond-like carbon, Hydroxyapatite, …). Diamond-like carbon (DLC) is a metastable form of amorphous carbon containing bonded carbon atoms of sp2 and sp3 hybridized orbital. DLC layers are semiconductors with high mechanical hardness, chemical inertness, low coefficient of friction, high thermal conductivity, good electrical and optical properties, biocompatibility and no cytotoxicity. All properties of the films are not always ideal, so it is necessary to modify the layer. One example of how to modify the properties of thin layers are dopations. The incorporation of dopants in films may lead to greater multifunctionality and much improved properties. Most modifications were made to modify contact angle and surface energy, to reduce internal stresses, to decrease surface roughness, coefficient of friction or wear....
|
guest ::
