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The effect of the operator on the accuracy of the estimates of lean meat share in pigs
Jiravová, Renata ; Šprysl, Michal (advisor) ; Libor , Libor (referee)
The aim of the study followed the determination of operator error, ie repeatability, or influence of the measuring point on the accuracy of the estimate of lean meat share (LMP). It was a FOM-SFK instrument measured at prescribed locations the backfat thickness, muscle depth, and thus their LMP in their carcass realization in SEUROP system. For this purpose a total of 71 hybrid pigs (Dan-Bred) were measured at the Velvary slaughterhouse. In order to determine the error from incorrectly determined place of measurement, the following six classification insertions were done per one animal, thus 1. 2nd -- 3rd last rib 7 cm off the midline (right point), 2. 2nd -- 3rd last rib 7 cm off the midline (repeat in the same hole), 3. 2nd -- 3rd last rib 1 cm caudal to the right point, 4. 2nd -- 3rd last rib 1 cm cranial to the right point, 5. 3rd -- 4th last rib 1 cm medial to the right point, 6. 1st --2nd last rib 1 cm lateral to the right point. Measurements were performed on the carcass that insertion 2 should be identical with insertion 1, insertions 3 and 4 were moved 1 cm off insertion 1 in the cranial or caudal direction and insertions 5 and 6 were moved by 1 rib from insertion 1 in the cranial or caudal direction respectively. Classification was held by FOM instrument, for further comparison also by ZP method. For the above classifications following regression equations were used. For: - FOM y= 81,8909+0,2006*M+14,1911*ln S, kde M=MLLT depth, S =backfat thickness, - ZP y= 76,6722--1,0485*M+0,00794*M2--0,002884*S2+9,0151*ln (M/S), kde M = MLLT depth, S= backfat thickness. Calculation and comparison of the results was performed by statistical program SAS Propriety Software Release 6.04, differences were tested by analysis of variance. Based on the results we can say that a given hypothesis was confirmed. Also, in the realization of slaughter pigs in SEUROP system can be stated that - by invasive technique FOM - precise LMP determination of the carcass is a function of the need for precise determination of the puncture site of operator, - accuracy of the backfat thickness as well as LMP estimate is affected by repeated punctures, - more reliably is measured the backfat thickness with repeated injection than the muscle depth due to its possible deformation, - inaccuracy of repeated measurements (repeatability) will not significantly affect the carcass classification into classes at the slaughterhouse; any errors will occur to the detriment of the supplier, - the injection shift 1 rib cranially respectively caudally affect the overall carcass classification more than shift the injection 1 cm medially or laterally away from the spine, - in the case of an unsuccessful measurement the best is to repeat the puncture or the second puncture shift 1 cm caudal or repeat puncture between the 2nd and the 3rd thoracic vertebra 1 cm towards the spine, - non-invasive technique ZP, compared to FOM, underestimates the LMP estimate by about 1,4%.

The tree inventory in gardens in Dobrissko region
Lexová, Jana ; Janeček, Vladimír (advisor) ; Vítámvás, Jan (referee)
Diplom work is describing woody composition of gardens in locality Dobříšsko. There were researched 50 gardens in this locality. Basic dandromatical parameters were found out (height, diameter of trunk, diameter of tree crown), the age of tree was estimated (determined), vitality and health condition of individual wood were rated and then care about greenery vas rated. Basic dandrometrical quantities were got with help of methodics of Agency for nature conservation and landscape Valuation of trees outside forests. The information about care about greenery, about tree felling, about signs of drought in 2015 were found out by questionnaire. Researched data were subdueded basic statistical analysis in program Microsoft Excel.

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.

Electric Drive Diagnostics and Utilization in Agricultural Machinery
Čedík, Jakub ; Pexa, Martin (advisor) ; Kumhála, František (referee)
This doctoral dissertation thesis deals with rotary mowers, specifically with the issue of mulching. In the theoretical part the reader is being familiar with the technology of mulching and its importance. Further, the individual types of mulchers and its advantages and disadvantages are described. The literary analysis of energy demands of rotary mowers is stated. Further, the parameters influencing energy demands of the mulcher are also analyzed. The results of measurement of the energy demands of the mulcher with vertical axis of rotation are presented. The dependency of input power, specific energy consumption and fuel consumption on mass performance of the machine are created. Furthermore, the energy demands was determined, while mulcher was working continuously at the permanent grassland. The energy losses of the mulcher were also analyzed. The effect of modification of operational and constructional parameters on the energy demands and quality of work of the mulcher wit vertical axis of rotation is studied. From the constructional parameters the shape of working tool, especially cloth angle and rake angle of the tool, and shape of the cover of the mulcher workspace is modified. From the operational parameters the cutting speed and mass performance according to conditions is modified.

Construction and scientific implementation of mathematical models for tree compartments of broadleaved trees in growth stages of seedlings and young stand
Pajtík, Jozef ; Konopka, Bohdan (advisor) ; Monika, Monika (referee)
Importance of precise estimation for tree biomass in forests has been continuously increasing. Regarding to the climate change, scientists have started to quantify all tree components not only in terms of energetic utilization but also for carbon stock estimation. Increasing relevance of biomass models for young trees relates to expanding area of young forest stands during the last period due to decay of old forests often caused by disturbances (especially: windstorms, outbreaks of bark beetles, drought episodes, and forest fires). Models for biomass stock estimations constructed for stands with age to 10 years are rare and usually are focused on aboveground tree parts. Thus, this work aims at filling knowledge gaps in this field. Its main objectives are: 1) construction of regression models applicable for estimation of dry mass in the particular tree components (i.e. stem, branches, foliage, roots) for young stands of some broadleaved species, 2) implementation of regression models for calculation of biomass conversion and expansion factors (BCEF), allocation coefficient, growth efficiency and leaf area index (LAI) and their inter-specific comparison, 3) utilisation of allometric relations for estimation on forage potential for ruminating ungulate game (i.e. browsing and stripping). To make up the models, destructive tree sampling will be implemented. The sample trees will be excavated, separated into tree components, dried for constant weight and weighed. Log-transformed relationships will be used for construction of regression models.

Optimization of microclimate parameters in dairy farms, while reducing the energy consumption of selected technological systems
Češpiva, Miroslav ; Pecen, Josef (advisor) ; Ján, Ján (referee)
Thesis is focused on the measurement and evaluation of microclimate parameters in barns for dairy farming and the determination of the energy consumptions of selected technologies in these barns. The aim of this work was to design and eventually to implement adjustments in order to improve the parameters of cowshed microclimate and reducing the energy consumption of selected technologies in depends on results of the measurements. Three structurally different cowsheds with different slurry clearing technologies were selected for monitoring. I focused on the measurement of temperature and relative humidity in relation to temperature- humidity index and its impact on heat stress on dairy cows. I measured airflow in the cowsheds and I determinate concentrations and emissions of ammonia and methane in the cowsheds in different seasons. I monitored light intensity in the cowsheds and I determined the dependence of building solutions on the use of outdoor light to illuminate the interior of the barns. The energy consumption of the lighting system depending on the season and the consumption of additional fans on the air temperature were studied. On the bases of results of the experimental part I designed and implemented lighting system, controlled by light intensity in a cowshed and energy-saving ventilation in the cowshed - type K105. I suggested a system of continuously monitoring of climatic parameters in the cowshed with immediate calculation of temperature- humidity index. Measurements have shown the dependence of gases concentrations on the way of slurry clearing technologies. The building solutions of cowsheds and type of ventilation proved a significant influence on the temperature- humidity index during the summer.

Airtightness estimation of wood based residential houses using Blower-door test
Srba, Jaromír ; Böhm, Martin (advisor) ; Trgala, Kamil (referee)
This dissertation analyses airtightness of residential buildings which in many ways influences their energy performance and therefore also their costs of use. Properly conducted airtightening layer can significantly extend the lifespan of the construction. The main objective of the dissertation is to evaluate the construction of newly built buildings in the Czech Republic and to assess the most important parameters which affect airtightness. The Blower-door test was used to assess air leakage. This method belongs among the most widely used and conclusive methods of analysis. Its advantage is mainly the fact that it can detect construction defects of the airtightening layer in important stages of construction (and possibly enable these defects to be corrected before completion). The core of this method is to create a pressure difference of deltap 50 Pa between the exterior and the interior of the building and at the same time discover the faulty places which are different for positive and negative pressure. The air leakage was assessed in 345 residential buildings constructed between 2006 and 2016, especially in conventional wood frame buildings or with buildings made from wood panels such as cross-laminated timber. The development of values of air change rate through the building envelope was evaluated according to the Czech standard ČSN 73 0540-2 and the results were compared to previous outcomes of other authors. Analysis and photo documentation of the most frequently detected leakage points are also part of the dissertation. A significant decrease in values of the air change rate was discovered, on average by 40.49% in 2016 compared to 2006, while for passive houses the air change rate values were almost steady. For buildings with wood frame construction, it was the way of ventilation which was determined as the most significant parameter affecting air leakage. For wooden buildings with natural or combined ventilation, the average value of air change rate at the pressure difference of 50 Pa was 1,29 h-1, for buildings with mechanical ventilation and heat recovery it was 1,18 h-1 and for buildings with very low energy consumption for heating with mechanical ventilation and heat recovery it was 0,44 h-1. Other parameters affecting the values of air leakage include the construction company, the presence of a chimney, the place and method of construction of the wood frame construction.

Application of optimization methods in hydrological modeling
Jakubcová, Michala ; Máca, Petr (advisor) ; Hanel, Martin (referee)
Finding the optimal state of reality is the main purpose of the optimization process. The best variant from many possibilities is selected, and the effectiveness of the given system increases. Optimization has been applied in many real life engineering problems as in hydrological modelling. Within the hydrological case studies, the optimization process serves to estimate the best set of model parameters, or to train model weights in artificial neural networks. Particle swarm optimization (PSO) is relatively recent optimization technique, which has only a few parameters to adjust, and is easy to implement to the selected problem. The original algorithm was modified by many authors. They focused on changing the initialization of particles in the swarm, updating the population topology, adding new parameters into the equation, or incorporating shuffling mechanism into the algorithm. The modifications of PSO algorithm improve the performance of the optimization, prevent the premature convergence, and decrease computation time. Therefore, the main aims of the presented doctoral thesis consist of proposal of a new PSO modification with its implementation in C++ programming language. More PSO variants were compared and analysed, and the best methods based on benchmark problems were applied in two hydrological case studies. The first case study focused on utilization of PSO algorithms in inverse problem related to estimation of parameters of rainfall-runoff model Bilan. In the second case study, combination of artificial neural networks with PSO methods was introduced for forecasting the Standardized precipitation evapotranspiration drought index. It was found out, that particle swarm optimization is a suitable tool for solving problems in hydrological modelling. The most effective PSO modifications are the one with adaptive version of parameter of inertia weight, which updates the velocity of particles during searching through the multidimensional space via feedback information. The shuffling mechanism and redistribution of particles into complexes, at which the PSO runs separately, also significantly improve the performance. The contribution of this doctoral thesis lies in creation of new PSO modification, which was tested on benchmark problems, and was successfully applied in two hydrological case studies. The results of this thesis also extended the utilization of PSO methods in real life engineering optimization problems. All analysed PSO algorithms are available for later use within other research projects.

Evaluation of the effect of radiation on evapotranspiration estimates and drought indices
Mairich, Pavel ; Matula, Svatopluk (advisor)
Abstract Evaluation of the effect of radiation on evapotranspiration estimates and drought indices The severity of drought can be inferred from water balance, of which evapotranspiration is a component. The evapotranspiration estimates are often based on the FAO 56 methodology with the net radiation as the main input. Usually, however, the latter is not directly measured. This study investigates to which extent can the direct solar radiation and the long-wave net radiation measurements be replaced by calculation according to FAO 56 with constant or locally optimised radiation coefficients or, for the long-wave net radiation, the coefficients according to Penman (1948). The problem is demonstrated on data from the Solar and Ozone Observatory in Hradec Králové for 2011 and 2012. On average, the estimates of solar radiation are satisfactory even with the standard coefficients and can be improved by local optimisation of the coefficients. The estimates for particular days may considerably differ from reality. The long-wave net radiation estimate according to FAO 56 is, on average, by about 30 % lower than the measured long-wave net radiation or an estimate thereof based on locally optimised or Penman's coefficients, with the average differences between any two of the last three methods much smaller (less than 9 %). The inaccuracy of estimates for particular days is considerable, too. The average reference crop evapotranspiration according to FAO 56 with standard coefficients is therefore considerably higher (by about 15 %) than analogous evapotranspiration obtained from the measured radiation or according to FAO 56 with optimised or Penman's radiation coefficients. The cause is that grass in the observatory was not irrigated. It therefore occasionally suffered from water stress and got overheated. The use of FAO 56 with the radiation inputs measured or calculated using other than the standard radiation coefficients may underestimate the evapotranspiration and the need for irrigation.

Effect of evening primrose oil om selected physiological parameters of thoroughbred horses under training conditions
Mikešová, Kateřina ; Hučko, Boris (advisor) ; Václav, Václav (referee)
Physical exercise increases tissue demand for oxygen and cell respiration, resulting in the generation of free radicals and reactive oxygen species. Overproduction of oxidants exceeding the cellular antioxidant capacity results in oxidative stress. Oxidative stress leads to tissue damage of a wide range of biomolecules and causes metabolic changes that consequently influence performance. To protect against oxidative stress, the body has an effective antioxidant defence system, including non-enzymatic and enzymatic components. The antioxidative effect of evening primrose oil (EPO) administration on the oxidative stress of race horses during their regular training period was determined. The eight-week experiment was performed on ten clinically healthy thoroughbred horses. All the horses were enrolled in a regular training program. Eight weeks before the experiment, the horses were fed a diet which remained the same for the following eight weeks, only supplemented with 150 ml EPO (blood samplings 3 times). Total antioxidant reactivity, thiobarbituric acid reacting substances, uric acid, levels, activities of muscle enzymes, eg. aspartate aminotransferase, creatine kinase, and parameters of fatty acid metabolism such as triacylglycerols and nonesterified fatty acids were determined. Average values of TAS after supplementation with EPO rose gradually and were detected at significantly higher levels in the sixth week in comparison with the control. The concentration of malondialdehyde, measured as TBARS, decreased significantly compared with the untreated control. The activities of AST and CK fluctuated, but no disturbance was demonstrated in muscle homeostasis. The present results indicate that the total antioxidant activity of the thoroughbred horses fed a diet supplemented with EPO was higher, and it helped stabilize the permeability of the muscle cell membranes in the horses at full workload.