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Environment in China - current state, problems and perspectives
Salačová, Aneta ; De Castro, Tereza (advisor) ; Neumann, Pavel (referee)
The problematics of the environment has been underestimated in China for a long time. This country has been developing with incredible speed in the last three decades. The price for such growth is the current state of the environment in China. The thesis is divided into three chapters. The goal of this thesis is to evaluate the current state of the environment in China and the development of the stance of the Chinese government towards the protection of the environment in the new millennium. In connection with the economic growth is analysed the dependence on air pollution and Chinese GDP. Last but not least are offered possible solutions and perspectives of the future development of air pollution in China.
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Differences between men and women in the Czech labour market
Stroukal, Dominik ; Kadeřábková, Božena (advisor) ; Pavelka, Tomáš (referee) ; Němec, Otakar (referee)
This thesis consists of five articles that apply current world research on labor economics at the Czech Republic and confirms the significant differences between men and women in this market. It shows that gender has a significant influence on the preference on the labor market and, consequently, on employment and health. First, the thesis shows that preferences are relevant determinant of career and then we study the difference in preference of salary for men and women. Subsequently it shows that gender plays a significant role in explaining the relationship between homeownership, and unemployment, as well as unemployment and health. The first chapter was able to demonstrate that the preference for a career has a positive influence on the choice of career. The influence of higher education on prioritizing career proved to be positive and significant. Probability of a career choice is reduced by the presence of children, however, is not dependent on their number, which is contrary to the theory of preferences. The second chapter shows that Czech women prefer more non-monetary rewards than men. It has also been shown that people with university education are same in the preferences of non-monetary rewards regardless of the gender of the respondents, however, compared to the world's research, the Czech higher education increases this preference. It turned out that women prefer risk less than men. The third chapter demonstrates that although the housing market undermines labor mobility and employment in the Czech Republic at the regional level, therefore, that in regions with a higher rate of home ownership is higher unemployment, at the individual level, the owners of housing are unemployed are less likely. The estimates are significantly different for men and women. Men living in owner-occupied housing have a higher likelihood of employment than women. At regional level, however, this thesis shows that the high rate of home ownership increases unemployment for both men and women, in the long run only to women. The fourth chapter showed that men transition to homeownership reduces the likelihood of unemployment next year. For women, this relationship has proved to be insignificant. In addition, as insignificant showed the opposite relationship, the transition from unemployment to the newly acquired home ownership. The last chapter shows that the change in the working status to unemployment will increase in the future probability of worse health. Influence in less than two years, however, proved to be significant. An important conclusion is that men have a significantly stronger relationship between health and unemployment than women.
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Aspects of the virtualization of higher education and its comparison in the CZ and US
Dlauhá, Dominika ; Šedivá, Zuzana (advisor) ; Pour, Jan (referee)
The topic of this thesis is the evolution of online higher education in the CZ and US, from its beginnings to its current state. Emphasis is placed on describing MOOCs and virtualization in education, ranging from technological, pedagogical and didactic aspects to legislature and finance. A survey was conducted to determine the interest in online courses at the University of Economics, Prague and experience with online learning, resulting in an outline of the future development in this area.
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Building and use of smaller computer networks
Kyzivát, Marek ; Pinkas, Otakar (advisor) ; Šmejkal, Ivo (referee)
The thesis describes the initial state of the computer network Basic Schools and Kindergartens Ohradní (ZŠMŠ Ohradní) in Prague 4 and then its reconstruction, which I largely contributed. ZŠMŠ Ohradní consists of four pavilions and from one building on the other side of the street. The aim of this study is to assess the initial state of the network and point out the shortcomings that we discovered. We found deficiencies in the operation stress tests, measurements and data cabling overall analysis. Original networks connectivity was 100Mb/s. Together with a colleague, we are network administrators. Furthermore, I am going to introduce a new form of network, which has identified deficiencies improved, by using on newer technologies. I will describe its structure, address allocation, active and passive components, and operated services. New network is capable of 1Gb/s, and its spine is going to be 10Gb/s soon. Benefits of this reconstruction is faster, more stable and more modern network that will facilitate the work of employees of ZŠMŠ Ohradní. To these improvements, I have mainly contributed by measurements. I participated in the design and implementation of new form of data network. I collaborated with fellow Poc to the configuration of active elements and network services in reconstructed network.
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The current state and prospects for sustainable development of tourism in Slovakia.
Libantová, Silvia ; Indrová, Jarmila (advisor) ; Chaloupka, Radek (referee)
Tourism contributes to the prosperity of destinations by bringing financial resources, new jobs, a higher level of services and infrastructure development. However, if tourism does not develop sustainably, it is accompanied by negative factors, as well. Especially, negative impacts on the environment, such as: water and soil contamination, increased noise and overcrowded destination during the high season. As a response to the worsening state of the environment and possible irreversible changes caused by irresponsible human behavior, the idea of sustainable development is becoming more important. The theoretical part describes tourism in the Slovak Republic and highlights plans for sustainable tourism development. In the practical part, the results of the questionnaire, related to the awareness of sustainable tourism in the Slovak Republic, are evaluated. The main objective of this thesis is to evaluate the current situation in the field of sustainable tourism and to make suggestions for its future development.
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INFLUENCE OF LASER CUTTING AND PUNCHING ON MAGNETIC PROPERTIES\nOF ELECTRICAL STEEL M470-50A
Bulín, Tomáš ; Švábenská, Eva ; Hapla, Miroslav ; Ondrůšek, Č. ; Schneeweiss, Oldřich
Electrical steel M470-50A belongs to the most often used materials in electrical machines. Due to this fact, it is desirable to know the magnetic parameters after processing raw sheets into the required shape. Basic parameters of mechanical, electrical, and magnetic properties of the sheets are usually obtained from the producer but the magnetic properties are changing in dependence on additional machining processes. The aim of this study is to describe changes in parameters of magnetic behavior after punching, laser and spark cutting of the original sheets. The basic information of structure was obtained by optical and scanning electron microscopy. The magnetic parameters were acquired from the measuring of magnetic hysteresis loops in dependence on saturation fields and frequencies. The results are discussed from the point of view of applied\ncutting technology with the aim to obtain the best magnetic parameters and consequently a higher efficiency of the final product. Results can be used as input parameters in simulation of the electrical machine.
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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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Arctic tundra dendrochronology
Lehejček, Jiří ; Svoboda, Miroslav (advisor) ; Monika, Monika (referee)
Historically unprecedented environmental change in the Arctic ecosystems is often given into the context of its past and possible future development. In the region where instrumental meteorological observations are scarce archives need to be investigated in order to address this issues. The comprehensive synthesis one of the archives: long-live circumpolar evergreen Juniperus communis L. shrub is presented here. 20 individuals from southwest Greenland were investigated at the cell anatomy level to understand the ecology of the species and unhide its potential for environmental and climate reconstructions. The findings are as follows:
i) Stop of exponential cross-sectional conduit-lumen widening with increasing age is in contrast with conduit-lumen nature of trees. This indicates that shrubs do not need to saturate their water and nutrient demands via traits of classical hydraulic conductivity law but rather developed different mechanisms. Extreme weather conditions result in prostrate growth form. However, different weather factors probably influence shrub growth differently: While snow and wind act mechanically (a), temperature influences the form of growth physiologically (b). a) So long as the young shrub stem has high resilience to bend back to an upright position after snow melt and so long as it can withstand the wind during the vegetation season it most likely grows upright and the conduit-lumens widen. b) Temperature, resp. freeze-thaw events are responsible for the shrubs preference of safety (finite size of conduit-lumens) over hydraulic efficiency, thus not allowing for more primary growth. All of these (and other) factors are apparently working together and the transition of vertical to more horizontal growth is gradual. As a consequence, the conduit-lumen sizes may not have to be further increased (due to ecophysiological restrictions possibly also must not) because water is no longer transported against gravity.
ii) Observed age/growth trend has to be taken into consideration for further employment of the wood anatomical parameter in paleoenvironmental studies. That is, shrub cell parameters can only be used for this purposes if correctly detrended. This allows for more accurate as well as longer reconstructions because youth trend was often neglected in reconstructions based on shrub annual-rings.
iii) The south-western Greenland Ice-Sheet (GrIS) melt rates reconstruction is presented for the whole 20th century. This part of GrIS is considered as the most active. According to the presented reconstruction current GrIS melt rates are not uncommon for the last century being comparable to first decades of 20th century. This finding is particularly important contribution to the debate on Atlantic meridional overturning circulation (AMOC). Too high fresh water inputs into the Northern Atlantic from GrIS melting may slow down or even stop the AMOC which would result in more continental climate in Europe. Presented results indicate that this threshold lies higher than observed current melt rates of GrIS.
Fascinating Juniperus comunnis species has shown to be able to address many ecological as well as environmental open questions and due to its longevity and abundant distribution has a great potential to become an important player in the Arctic research.
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Freezing technology of bull sperm in relation to its survivability and fertilization ability
Doležalová, Martina ; Stádník, Luděk (advisor) ; Jiří, Jiří (referee)
The aim of optimalization the insemination doses production is to provide the highest fertilization ability of spermatozoa during the demanding proces of processing fresh semen and its subsequent cryopreservation. Temperature changes causes spermatozoa damage during the cooling and freezing. Spermatozoa is exposed to cold shock and many others limiting factors, which leads to cell death and therefore to decline of fertilization ability of thawed insemination doses. For increasing spermatozoa resistance, exactly the plasma membrane resistance against cold shock was fraction of egg yolk LDL cholesterol (low density lipoprotein) at various concentrations into the comercially produced diluents added. It is believed that LDL acts possitively to plasma membrane and helps to maintain the fertilization ability of spermatozoa after thawing. Following step in the proces of insemination doses production is slow cooling of diluted semen and equilibration, when the straws are store at cooling box for 30 minutes to 240 hours. This period is necessary to penetrate of certain diluent components into the spermatazoa also maintain the balance between their intracellular and extracellular concentration. Also important is subsequent freezing temperature gradient of insemination doses. The most suitable freezing method is based on computer controlled temperature decline in freezing chamber which allows the precise control of ice crystals formation that could tear and kill the cell.
During 2012 to 2016 was repeatedly collected semen from the group of breeding bulls (n = 27, Holstein and Czech Fleckvieh breed) at AI centre. Semen which fulfill the standard entrance conditions in first step was evenly into several parts divided. For dilution the three types of comercially diluents AndroMed, Bioxcell and Triladyl with and without LDL addition were used. Into the diluents AndroMed and Bioxcell the concentration of LDL 4 %, 6 % and 8% into the dilent Triladyl 6 %, 8 % and 10 % was added. Diluted semen was filled into the glass capillares with volume 0,1 ml and temperature +4 °C. Subsequently the sample was placed to cold bath (0°C) for 10 minutes. Then the volume of capillare with physiological solution (37 °C) was mixed and for next 120 minutes was incubate. The effect of cold shock to proportion of live spermatozoa was evaluated by using Eosin and Nigrosine staining technique during heat test of spermatozoa survivability after spermatozoa heating and after 120 minutes of incubation.
The more suitable semen diluents which provide the higher spermatozoa resistance against cold shock were AndroMed and Bioxcell. Together the possitive effect of LDL addition into the diluents to lower decrease of proportion of live spermatozoa during heat test was found (P<0.05). The most suitable LDL concentration which had a favorable influence at spermatozoa resistance against cold shock was 6 % in diluent Bioxcell. Values of the proportion of live sperm were higher at the beginning of the heat test (+1.31% to + 3.2%) and after 120 minute incubation (+5.82% to +8.41%) compared to other diluents with and without addition of LDL.
In the next step the process of equilibration was optimized, is an important part of insemination doses production. The effect of the length of equilibration for subsequent fertilization ability of spermatozoa was evaluated using spermatozoa motility based of CASA and proportion of live spermatozoa after thawing and during heat survival test lasting 120 minutes (37 ° C). Suitable semen was diluted by comercially used diluent AndroMed based on soya lecithin, filled into the straws (0.25 ml), cooled and equilibrated in cooling box for 30, 120 and 240 minutes and freezed in programmable freezing box applying four types of freezing curves differing in temperature rate decline. There was used standard and by producer recommended 3. phase freezing curve, then 2. phase freezing curve, and 3. phase freezing curve with slower as well as rapid decline of temperature rate in freezing chamber, compared with standard freezing curve. The highest spermatozoa motility was found using 240 minutes of equilibration by +2.72% and +4.58% compared to other lengths of equilibration (P <0.05 to 0.01). The highest proportion of live spermatozoa was found using 120 minutes of equilibration (+6.87 % and +8.68 %). The highest average spermatozoa motility during heat test after thawing was achieved by using 2. phase freezing curve (from +2.97% to +10.37%, P <0.05), also in the proportion of live spermatozoa (from + 4.37% to +8.82%, P <0.01). When evaluating interaction between the length of equilibration and freezing curve (standard 3. phase and 2 . phase freezing curve), the highest average spermatozoa motility and proportion of live spermatozoa using 240 minutes of equilibration by both freezing curves was reached, there was no statistically significant differences. As well as, in all evaluated parts of this study the individual differences between ejaculate of bulls and within semen from one bull (P <0.05) as secondary effect were found.
To maintain good fertilization ability of semen during cryopreservation is necessary to increase the spermatozoa resistance against cold shock using addition of correct concentration of LDL into the commercially used diluents AndroMed and Bioxcell. Subsequently the fertilization ability of insemination dose is influenced by cooling, the length of equilibration and freezing. The length of equilibration 120 minutes and more as well as gentle way of freezing according to freezing curve, which ensures a gradual decrease of temperature in freezing chamber provided the higher average spermatozoa motility and proportion of live spermatozoa.
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