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Global Economy Outlook - September 2016
Česká národní banka
The September issue of Global Economic Outlook presents the regular monthly overview of recent and expected developments in selected territories, focusing on key economic variables: inflation, GDP growth, leading indicators, interest rates, exchange rates and commodity prices. In this issue, we also focus on the closing of the output gap in OECD countries in the current low-inflation environment. We point out that the output gap is currently closing at near-zero inflation rates rather than at rates close to 2% (corresponding to the generally accepted price stability criterion). The current output gap and inflation outlooks signal a gradual return to the output gap closing at consumer inflation rates of approximately 2%.
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Analysis and modeling of the structure and development of mixed forest stands in the Sudety mountains
Vacek, Zdeněk ; Remeš, Jiří (advisor) ; Hlásny, Tomáš (referee)
The thesis deals with analysis and modeling of the structure and development of selected mixed forests in protected areas of the Sudeten system, especially in the Giant Mountains national parks, Protected Landscape Area Broumovsko and Orlické Mountains, but also in other areas of the Czech Republic. This study is composed of a set of six published manuscripts that are covering three thematic ranges: structure of forest stands, regeneration of forest stands and forest modeling. The main objective of this work was to evaluate a vertical, horizontal and species structure, total diversity and development of mixed forest stands in central Sudetes. The partial aim was to analyse production parameters of forest stands, effect of microrelief and game on natural regeneration and assessment of dead wood in the area of interest. Further, the objective of the study was to develop explicit and non-explicit crown width and slenderness quotient models for Norway spruce (Picea abies L.) and European beech (Fagus sylvatica L.) and to predict the development of mixed forest ecosystem using growth simulations and to evaluate parameters and interactions among stand structure, climatic factors and natural regeneration, using especially analysis of variance, correlation matrix, spatial statistic and multivariate analysis. For this purpose a system of permanent research plots was used, which are regularly monitored since 1980 or were newly established. Using mapping technology FieldMap, selected parameters were measured for tree layer, natural regeneration individuals and dead wood. The results showed that the spatial distribution of beech stands in optimum stadium changes with the altitude from the regular pattern through random to aggregated spatial pattern of beech forests near the timberline. The spatial distribution of natural regeneration is highly aggregated, distribution of stumps is random and horizontal structure of the centroids of the crowns is always more regularly distributed than stems due to crown plasticity. Browsing damage of the leading shoot by game is an important limiting factor for height growth of natural regeneration, especially for silver fir (Abies alba Mill.), rowan (Sorbus aucuparia L.) and sycamore maple (Acer pseudoplatanus L.). The study of the influence of microrelief on the growth of beech regeneration showed that the highest average height was found on slope and pits, while the lowest on the mounds. From the effect of climatic factors on the radial growth of trees, it was found that temperature is a limiting factor for growth in mountain areas, respectively that positive effect of temperature decreases with decreasing altitude and conversely the influence of precipitation increases. Finally, spatially explicit models (as opposed to non-explicit) described a larger part of the crown width variations for spruce and beech and of the slenderness quotient for spruce. The largest contribution to the models after breast diameter was dominant height.
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Structure, development and growing spruce-beech stands in the western Giant Mountains
Bulušek, Daniel ; Vacek, Stanislav (advisor) ; Michal, Michal (referee)
The subject of dissertation is to evaluate the structure, development and silviculture spruce-beech stands in the western Giant Mountains and design of differentiated silviculture of these stand in similar environmental conditions. The aim of this study was to describe the structure of trees natural regeneration and the structure of tree layer, evaluate their current development and to predict future developments and based on detailed analysis of habitat and stand conditions to propose a framework directive management of the studied stands and stands located in similar habitat and stand conditions in the Giant Mountains. For this purpose were used primarily permanent research plots (PRP) 1, 2, 8, 9 and 35 with the dimensions of 50 × 50 m, which were established and regularly monitored since 1980 (PRP 1, 2, 8 and 9), PRP 35 were established in 2004 and a number of other sub-plots. For the evaluation of natural regeneration was on each research plot marked transects 50 × 5 m (250 m2). Measurement of the natural regeneration included all individuals present at the individual transects, whose diameter breast-height diameter was smaller than 7 cm. After measuring all the data was evaluated spatial, species, height and thickness structure. To evaluate the tree layer were measured all individuals on permanent research plot with breast-height diameter greater or equal than 7 cm. The measured data were subsequently evaluated by mathematical-statistical methods. Visualization of the tree layer and development simulation was performed using the growth simulator biodynamic of forest SIBYLA. The results show that the structure stands was on individual permanent research plots very variable. Variability occurred in natural regeneration even within individual transects. Significant differences are evident in the development of stands that provide space for a wide range of near natural differentiated care within of stands type and individual types and subtypes of forest development.
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Possible solutions to the restoration of overmature forest stands in the Lány game enclosuregame-park
Ambrož, Robin ; Vacek, Stanislav (advisor) ; Igor, Igor (referee)
Possible solutions to the restoration of overmature forest stands in the Lány game enclosure -- this is a problem that generations of foresters in the Křivoklátsko region have been faced with. The restoration has often been postponed; as a result, there has been a remarkable increase in the number of such stands in the game enclosure. Currently, almost a third of the game enclosure is covered by stands, predominantly beech, older than 160 years, and the suggestions on how to restore these stands are by no means unified, not only within the framework of the relevant authorities, but also among the management of the Lány forestry administration. In the past, the disintegration of stands in the highest age class was dealt with by a massive planting of large-sized plants in the whole area of the game enclosure, which has brought and will continue to bring about a remarkable increase in the forest protection costs. The aim of this PhD thesis is to answer the questions concerning the restoration of the local beech stands and to propose a solution that would be efficient in the long term. The basic questions have been phrased as follows: In what condition are the extensive large-sized plant plantings? What is the number of overmature forest stands in the Lány game enclosure and what will their future development be? Are these stands still capable of producing a sufficient number of beech seeds to ensure successful natural regeneration? In what way should we restore these overmature forest stands? How should we protect them from the game damage? It was necessary to find some of the answers within the framework of intermediate scientific tasks; however, the finding of a conceptual solution to the restoration of the game enclosure remained the main goal of this work. To fulfil the goals of this thesis, it was necessary to perform the inventory of large-sized plant plots; it was found out that the total number of individuals planted in the Lány game enclosure until the end of 2011 was 28,994 at 840 plots. The plantings established in 2011 were surveyed as to their vitality and height increment between the years 2011 and 2014. In 2015, a sample was selected on which the condition of the root system was analysed according to the type of a container used for the raising of large-sized plants. It is evident from the results that despite considerable investment in fencing, the large-sized plant plantings are very often damaged by game and have to be repeatedly reinforced. The root system analysis revealed that a significant number of individuals show serious root system deformations. Consequently, the optimization of large-sized plant planting was proposed. The condition of the beech stands at PRP was ascertained with the aid of the FieldMap technology; the stand development prediction was carried out by the growth simulator SIBYLA. The verification of the fertility of the overmature beech stands took place at smaller plots demarcated within PRP. The results show that the occurrence of game eliminates natural regeneration in these stands; thus, it is necessary to find a way which will not be only efficient, but also economical. The fertility verification proved that despite their advanced age, the beech stands preserve their ability to produce seed material, which could be used for regeneration under a shelterwood. Finally, a model regeneration block presenting two possible reproduction methods (with maximum utilization of natural regeneration and accelerated one) was designed on the basis of both the differentiation of the game enclosure and the localization of stands with the highest degree of regeneration urgency.
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The most important dietary sources of lipophilic vitamins
Šafránková, Simona ; Hejtmánková, Alena (advisor) ; Táborský, Jan (referee)
Basic piece of knowledge about nutrition and its need should be integral to every mans general knowledge. One of the vital nutritions ensuring a full-functioning organism are vitamins. Vitamins are essential ingredients, which play an important role in the human body and also in the processes of absorption and the exchange of substances between the external environment and living organism. They were discovered recently during the 20th century. The researches on their effects on the human body are still ongoing.
The vitamins are divided into two basic groups, water soluble vitamins, the so called hydrophilic (vitamins B and C), and fat soluble vitamins, the so called lipophilic (vitamins A, D, E and K).
The vitamin A is important to ensure good vision and recognizing colors. It support the quality and growth of bones, affects the egg and sperm and is needed for proper fetal development.
Vitamin A is found in foods of animal origin, such as dairy products, milk, meat and liver. In the food of plant origin, the vitamin A is replaced with many provitamins, of which most important is the beta carotene. A very rich source of these provitamins are leafy greens such as spinach or cabbage.
The recommended daily intake of vitamin A is 800 microgram, according to the standards of Czech republic. This need depends on the gender and age of each individual. The lack of vitamins A causes photophobia and impaired vision. The excess of vitamin A may be toxic for the organism. The interesting fact is that the beta carotene is not considered to be toxic.
Vitamin A is one of the labile vitamins. It is sensitive to heat, light and oxygen. At a gentle meal preparation and usual diet, the losses are around 20 %.
The vitamin D is consisted of group of several biologically active substances, of which the most important are vitamin D2, ergokalciferol, to be found in foods of plant origin, and vitamin D3, cholekalciferol, to be found in foods of animal origin.
In the human body, vitamin D acts as a hormone, it is formed at one point of the organism, but affects a different part of the body. The vitamin D ensures the intake and absorption of calcium and phosphorus and maintain their balance. It supports the immune system and may help in the psoriasis treatment.
The recommended daily intake of vitamin D is about 2,5 to 10 microgram. Pregnant and lactating women have a greater need for it, as well as infants and children. The lack of vitamin D disturbs the homeostasis of calcium and phosphate metabolism. The excess of vitamin D causes hypercalcaemia.
The most important foods source of vitamin D are liver, oil from fish liver, oil sea fish, fortified margarine and milk.
Vitamin D is sensitive to oxygen and light, its activity is not significantly affected by food storage or preparation.
Vitamin E is a major antioxidant. It is important to maintain the healthy cell wall and skin, muscles, nerves, erythrocytes, heart, and it is also responsible for the proper function of blood circulation.
The recommended daily intake of vitamin E is 8 to 20 mg. Its need is increased during exposure to sunlight and harmful influences, during increased physical exertion and when receiving large amounts of unsaturated fatty acids. The lack of vitamin E almost does not occur in healthy people, since it is present in nearly all basic kind of foods. The hypervitaminosis of vitamin E occurs only rarely, because there is no risk of overdose when receiving a normal diet.
The most important foods source of vitamin E are vegetal oils (such as sunflower and rapeseed), nuts, corn, pea, corn products, dark green leaf vegetables, eggs, liver and viscera.
Vitamin E is considered the most stable lipophilic vitamin. There is only a minimal loss of tocopherol during food processing, these losses are approximately 10 %.
The vitamin K supports blood clotting in the human body and, along with the vitamin D, is involved in the constant bone development and remodeling.
Both foods of plant and animal origin are sources of vitamin K, such as meat, liver, milk, vegetables and fruit. The recommended daily intake of vitamin K is around 0,01 to 0,14 mg. The infants and children up to three years have lower need of vitamin K intake. The most common cause of vitamin K hypovitaminosis is disruption of intestinal microflora caused by various drugs, e.g. antibiotics. Too high doses of vitamin K can accumulate in the body and lead to the breakdown of erythrocytes, damage the liver and cause jaundice in children.
There is not much information known about the stability of vitamin K yet. It has been found that vitamin K decomposes rapidly in the light, however its losses during food processing are minimal.
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Vliv počtu soudců na výstup soudního systému
Jonáš, Václav ; Dušek, Libor (advisor) ; Vozárová, Pavla (referee)
The thesis examines the effect of the number of judges on court output in the Czech Republic. It is based on the theory of a rational judge and the hypothesis that after the appointment of new judges, the incumbent judges face lower caseload pressure and they can decrease their effort. It follows that the change in the court output is very small or non-existent. I develop a model that specifies court output as a function of judicial staffing, caseload and other variables. I employ OLS, FE and 2SLS estimation methods. The estimation results suggest that the number of judges does not affect court output in the case of district courts. In the case of regional courts, a 10% growth in the number of judges leads approximately to a 5% growth in the number of resolved cases. Furthermore, estimates suggest that all courts strongly react on changes in the caseload. I also show that the quantity-quality trade-off is not present at courts in the Czech Republic. The thesis contributes to thin empirical literature on the effect of judicial staffing on court output mainly by controlling for the case difficulty and by using panel data from the Czech Republic.
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Interspecific interactions in wetland communities in dependence on water regime: long-term test of stress-gradient hypothesis
Růžičková, Kateřina ; Douda, Jan (advisor) ; Alena, Alena (referee)
The Stress-gradient hypothesis predicates a change of interspecies relations from negative to positive according to the stress gradient. The basic assumption is that the presence of one species (the facilitator) makes the growth of other species easier. In this study was determined based on the 5years experiment, whether the interspecies interactions (i.e. the importance of facilitation and competition) changes according to the hydrological conditions. Three wetland species (Calamagrostis canescens, Carex elongata and Deschampsia cespitosa) were planted in experimental pots with the presence and absence of the dominant species (Carex elata). The hydrological gradient (= the stress gradient) was simulated by three types of hydrological conditions: dry, fluctuating and wet. The success of the species within the specific conditions was correlated with the fitness-related characteristics of the plants including the biomass, the number of ramets and the height of the plants. Following hypotheses were tested: i) at a low intensity of stress (with the wet treatment), the C. elata represents a competitor for other species. On the other hand, at a high intensity of stress (with the dry treatment), the C. elata represents a facilitator, making it easier to the other coexisting species to grow. This presumption was confirmed only with the D. cespitosa, which was more successful under dry treatment with the presence of a dominant species, which facilitated it. With the other two species the change of interspecific relations was not observed and the relationships remained negative. Furthermore the results showed, that in the dry treatment with the presence of a dominant species, there was a lower intensity of competition among the coexisting species. The experiment showed, that the interactions of particular species with dominant species can vary according to the stress gradient. The hydrological gradient also influences the character and intensity of interactions among the species.
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Determination of Fracture Mechanical Characteristics From Sub-Size Specimens
Stratil, Luděk ; Džugan, Jan (referee) ; Haušild, Petr (referee) ; Dlouhý, Ivo (advisor)
The standards of fracture toughness determination prescribe size requirements for size of test specimens. In cases of limited amount of test material miniature test specimens offer one from the possibilities of fracture toughness evaluation. Because of small loaded volumes in these specimens at the crack tip the loss of constraint occur affecting measured values of fracture toughness. In such cases the size requirements for valid fracture toughness characteristics determination are not fulfilled. These specimens can be even on limits of load range of test devices and handle manipulation by their small dimensions. The important task related to these specimens is, apart from methodology of their preparation and measurement of deformations, the interpretation of measured values of fracture toughness and their possible correction to standard test specimens. Moreover, in the upper shelf region of fracture toughness quantification and interpretation of size effects is still not resolved sufficiently. This thesis is by its aims experimentally computational study focused on evaluation of size effect on fracture toughness in the upper shelf region. The size effect was quantified by testing of miniature and large specimens’ sizes in order to determine J R curves. Two geometries of miniature test specimens, there point bend specimen and CT specimen, were used. The experimental materials were advanced steels developed for applications in nuclear and power industry, Eurofer97 steel and ODS steel MA956. Finite elements analyses of realized tests together with application of micromechanical model of ductile fracture were carried out in order to evaluate stress strain fields at the crack tip in tested specimens from Eurofer97 steel. By comparison of experimental results and numerical simulations of J R curves the mutual dependencies between geometry of specimens and element sizes at the crack tip were derived. On the basis of acquired relationships, the methodology of J R curve prediction for standard specimen size from limited amount of test material was proposed. Main contribution of thesis is description of effect of material’s fracture toughness level on resistance against ductile crack propagation in miniature specimens. For material where significant crack growth occurs after exceeding the limit values of J integral (Eurofer97), the loss of constraint is considerable and highly decreases resistance against tearing. Miniature specimens then show significantly lower J R curves in comparison with standard size specimens. This effect is the opposite to the behaviour of miniature specimens in transition region. In case of material with low toughness, in which significant crack growth occurs in the region of J integral validity (ODS MA956), the effect of constraint loss is small without large impact on resistance against tearing. In such case miniature specimens demonstrate comparable J R curves as specimens of larger sizes. Next important contribution is proposed methodology for prediction of J R curve from small amount of test material using micromechanical modeling.
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System Management Model of a Professional Service Firm
Hubík, Tomáš ; Křivánek, Mirko (advisor) ; Majerech, Vladan (referee)
In the presented work I devote to creating a computer model of a professional service firm using the theory of business modeling. The whole model was programmed using the application Vensim. Another part of this work was to use this model to answer some key questions about the professional service firms. I dealt with the issue of optimal volume and optimal size of potential orders. I have also studied the influence of marketing and employee productivity on business performance. Another part of the work was to find patterns in employees career growth and to monitor sales and quality of projects delivery. I also determined the size and characteristics of critical mass. Such a model could then be used to better understand patterns of companies in the professional services industry and we can use it to manage the company more effectively in this environment.
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Influence of bioeffector RhizoVital on the soil phosphorus availability and P uptake by maize
Beneš, Zdeněk ; Kulhánek, Martin (advisor) ; Černý, Jindřich (referee)
Phosphorus is likely to become, in the near future, a critical element in plant nutrition. The main reasons are primarily limited resources of P for fertilizer production. Therefore, it is necessary to look for a long term solution. One option is to use P -containing waste, such as sewage sludge, digestate or ashes. Another option arises from the fact that approximately 90 % of P in soil is found in non-bioavailable forms. Therefore, mobilization of these forms could secure enough P for plat growth in the long term horizon. So-called bioeffectors are developed for this purpose; to promote the accessibility of nutrients for plants. It is evident, however, that the application of bioeffectors alone could lead to a gradual outflow of the most P from the soil. Therefore the most favourable appears application of bioeffectors in combination with various phosphatic fertilizers or wastes. Especially rock phosphates, ash and digestate contain significant amounts of non-bioavailable P-forms. That implies that the joint application of these fertilizers and bioeffectors should lead to more efficient utilization of P, and thus reduce the input of fertilizers into the soil.
The aim was to verify influence of a combination of 3 bioeffectors (effective microorganisms: Bacillus amyloliquefaciens, strains FZB42 and FZB45, and the combination of FZB42 strain with Paenibacillus mucilaginosus strain JX - 1) in combination with rock phosphate, sewage sludge, torrefied sewage sludge, separated digestate, straw and wood ash on increase of aboveground biomass of maize and on the content and uptake of phosphorus and other selected nutrients.
The evaluated alternatives of fertilization regardless of applied bioeffectors suggest that the greatest effect on the yield of above-ground biomass showed sewage sludge, wood ashes, and especially straw ashes. These fertilizers significantly increased the content and uptake of S as well. In other monitored parameters it was not possible to clearly identify the tendencies.
The application of bioeffectors alone or in combination with the above mentioned materials did not bring the positive effect on the monitored parameters. On the contrary, the combination of Paenibacillus strains FZB42 mucilaginosus showed in many cases significantly negative impact.
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