National Repository of Grey Literature 25 records found  previous11 - 20next  jump to record: Search took 0.01 seconds. 
Compact Sensors for Evaluation the Thermal Comfort
Kazkaz, Mohammad ; Fiľakovský, Karol (referee) ; Šafařík,, Pavel (referee) ; Pavelek, Milan (advisor)
Teplota vzduchu je nejčastěji používaná k posouzení tepelného stavu vnitřního prostředí. Avšak teplota vzduchu sama o sobě, je v mnoha případech pro toto posouzení nedostatečná. Hlavním cílem disertační práce je vyhodnotit tepelný stav vnitřního prostředí a specifikovat parametry, které na něj mají vliv. Teplota vzduchu, střední radiantní teplota, rychlost vzduchu a vlhkost vzduchu jsou čtyři základní parametry, které určují tepelný stav vnitřního prostředí. Vzhledem k tomu, že tepelný stav prostředí závisí na mnoha aspektech, byly odvozeny veličiny, které zahrnují kombinovaný účinek několika nebo všech těchto parametrů k určení tepelného stavu prostředí. Jedná se např. o efektivní teplotu, teplotu kulového teploměru, operativní teplotu, ekvivalentní teplotu, PMV a PPD indexy... aj. V dnešní době existuje spousta vysoce přesných senzorů, které mohou zhodnotit tepelný stav vnitřního prostředí. Z důvodu jejich vysoké ceny jsou používané převážně pro účely výzkumu. Předkládaná práce se převážně soustředí na vývoj kompaktního deskového senzoru pro vyhodnocení tepelného stavu vnitřního prostředí. Zaměřuje se hlavně na nízkou cenu senzoru společně s dostatečnou přesností. K dosažení cíle této práce jsou provedeny následující postupy: • Analýza environmentálních faktorů ovlivňujících tepelný stav prostředí. • Studium dopadu teploty vzduchu, střední radiantní teploty a rychlosti proudění vzduchu na tepelné indexy: teplotu kulového teploměru a operativní teplotu. • Teoretické porovnání teploty kulového teploměru a operativní teploty. • Navržení, rozvoj a konstrukce nového deskového senzoru pro posouzení tepelného stavu vnitřního prostředí. • Navržení a konstrukce testovací komory pro porovnávání senzorů tepelného stavu prostředí. • Kalibrace zkonstruovaného senzoru měřením fyzikálních veličin charakterizujících tepelný stav prostředí. • Testy směrové závislosti vyvinutého deskového senzoru a porovnání s kulovým teploměrem v testovací komoře. • Srovnání teoretických řešení s provedenými měřeními v testovací komoře. Výsledkem této práce je vlastní teoretické srovnání teploty kulového teploměru a operativní teploty ve vybraném rozsahu teploty vzduchu, střední radiantní teploty a rychlosti vzduchu pro možnost hodnocení tepelného stavu vnitřního prostředí pomocí kulového teploměru. Hlavním výstupem je však navržení a zhotovení jednoduchého deskového senzoru, který by byl dostatečně přesný pro měření tepelného stavu prostředí. V rámci disertace byla postavena také testovací komora a bylo provedeno testování vyvinutého senzoru pomocí měřicího systému INNOVA.
Dispersal mechanisms of protists
Křivská, Lucie ; Škaloud, Pavel (advisor) ; Urbánková, Pavla (referee)
Protists are ubiquitous organisms, they are main particles in foodchains, but they also cause many economical problems in areas of healthcare, agriculture and in food industry. Their biogeography is discussed in many academical debates and even that our methods are relatively advanced, there is still not only one accepted theory but two of them. However it is true that the moderate endemicity model is probably the correct one. This text sums up our existing knowledge in the field of protist distribution and their dispersal over whole planet, in terrestrial and aquatic environments. Mechanisms of dispersal are very coplicated and complex problematics. The resting stages are also important for successful dispersal, not only as a reaction to unfavourable conditions. Dispersal is affected by climatic conditions in investigated area and thus it is not easy to predict the patterns of dispersal. Human influence is getting more important on biogeography of microorganisms, including the history. This topic is becoming more popular these days as it becomes obvious it is importnat to know the patterns of dispersal. There are also adaptations and tolerances discussed. Keywords: environmental factors, dispersal, distribution, endemic species
Effect of metapopulation structure and environmental factors on population biology of Impatiens noli-tangere infected by powdery mildew Podosphaera balsaminae
Chalupníková, Jana ; Koubek, Tomáš (advisor) ; Čuda, Jan (referee)
Studies performed on natural pathosystems revealed that the spatial structure of the metapopulation plays an important role in the development and spread of disease; phytopathological experimental studies have also revealed a significant effect of climatic factors on the presence of the disease (incidence) and the level of infection (prevalence) in populations. The aim of this study was to explore a natural pathosystem from both sides at the same time and to see which local and spatial environmental factors influence the development of pathosystem. Study focuses on population biology of natural pathosystem Podospaera balsaminae - Impatiens noli-tangere, which has not been investigated yet. In the study area (between the city Sázava (Benešov district) and village Vlkančice) host populations occurred in 78 (64 of them were infected) in 2013 and 82 populations (61 of them were infected) in 2014. Size of host populations had the strongest effect to incidence and prevalence of disease in the pathosystem. In larger populations, the disease occurred more often, developed faster and was higher. The rate of spread of the pathogen territory and the rate of population host connectivity had also strong effect. The abundance of pathogen in the studied area and the level of connectivity of host populations also...
The relation between morphological and personality traits in humans
Sýkorová, Kateřina ; Flegr, Jaroslav (advisor) ; Třebický, Vít (referee)
In humans, as in animals, associations or correlations between morphological and personality traits can be observed. Some of the most conspicuous and well describable morphological traits in humans are eye color, hair color, body height and body mass index (BMI). These traits can correlate not only with temperament or character, but also, for example, with intelligence. Relations between morphology and personality can have an origin on a genetic or an environmental level. The human psyche, which can be influenced by social factors, can also have a role in the chain of causes and consequences. In this study, known relations between morphological traits and personality are discussed and mechanisms which could be responsible for these relations are mentioned. This study also focuses on the possible role of the environment which could explain some associations between the traits. Further, there is an attempt to identify environmental factors contributing to the morphological and personality traits which could therefore be a cause of some correlation between these traits.
Northern Bohemia as a potential distribution area of the genus Tuber including summer truffles (Tuber aestivum)
Šťovíček, Václav ; Gryndler, Milan (advisor) ; Jablonský, Ivan (referee)
Truffles are economically important fungi that are naturally present in the territory of the Czech Republic. Their geographical distribution is traditionally documented by the field incidence of fruitbodies. Advanced detection methods, however, enabled us to detect the presence of Tuber spp. at localities without a need for finding the underground fruitbodies. In this work, a molecular genetic detection method based on the polymerase chain reaction with specific primers was used. It enables us to determine the occurrence of members of the genus Tuber including Tuber aestivum in the studied samples. Members of the genus Tuber were detected in 67 cases out of a total of 190 samples. Highly probably, Tuber borchii, Tuber foetidum, Tuber rufum, Tuber dryophilum, Tuber umbilicatum, Tuber huidongense, Tuber oligospermum and Tuber aestivum have been detected. Since the sequence similarity with the closest species is relatively low in some cases, some of the obtained sequences might belong to hitherto unknown truffle species. Environmental factors analyzed explain only a small portion of the variability, acted weakly and cannot be taken as decisive for the presence or the absence of a species in a sample. The occurrence of truffles in the slopes of the study area was noted and it seems to be still more...
Populační biologie rostlin napadených systémovými parazity
Koubek, Tomáš ; Herben, Tomáš (advisor) ; Šmilauer, Petr (referee) ; Wennström, Anders (referee)
Three separate studies of the effect of plant pathogen on population biology of its host are presented in the thesis. Two are using field data about a widespread system of plant Falcaria vulgaris and its systemic rust fungus Puccinia sii-falcariae. The first study shows, that the disease prevalences in 40 populations of the plant were correlated with the moisture, the soil reaction and the cover of the herb layer at the localities. This was probably a result of the interaction of the life history of the plant and different effect the disease has at various localities. Similar pattern was found in the second study that aimed to determine long-term effect of the disease at the population level at four chosen localities over 4-5 years. Population growth rates were only rarely predicted to be higher for the healthy part of the population when compared with the whole population. Other analyses have however found big differences among years and localities. The locality type (slope vs. field populations) was important factor influencing population stage composition and importance of life cycle transitions for the growth of the population. Finally, the last study explores the possibility that systemic infection in clonal plants might be able to select against clonality. The result of the modelling showed that more...
Vegetation changes in transition bogs at fishpond epilitorals
Spilka, Josef ; Karlík, Petr (advisor) ; Kindlmann, Pavel (referee)
This study concerns in a three peatland sites: the epilitorals of Pilská reservoir and Hořejší Padrťský fishpond in Příbram region and Kamenný fishpond in Pilsen. These peat-bobg were affected by negative conseqences of human activities. The aim of this study is to find out what kind these changes was and what extent they were. The changes in vegetation were observed from two points of view. The GIS analyses of aerial photographs represent the macroscale view. Repeating of old phytosociological relevées was the microscale view. To understand the cause of vegetation changes, the species-environment analyses were used. Four transects were made for this purpose and a water table level, pH and conductivity were mesured monthly along these transects. One-shot measurements of N and P water concentration and a peat depth were also carried out. Measured data from transects were uses in multivariate vegetation analyses and also in one- way analysis, aimed to an expansion plant species. All three sites of concern came through strong changes in past. In all of them the area of biotops of great conservation importance decreased and some endangered plant species have been lost there. The changes in Pilská reservoir epilitoral were mostly anthropogenic, whereas the mires of Hořejší Padrťský fishpond and Kamenný...
The influence of environmental factors on amphibian assemblages
Kára, Martin ; Pivnička, Karel (advisor) ; Frouz, Jan (referee)
Like a large part of western Europe also from the Czech landscape is dramatically disappearing amphibians. This negative trend occurred due to several factors, some of which is undoubtedly the most significant loss of suitable breeding areas. During the years 2009 and 2010 I monitored a total of 31 tanks in a part of the former districts of Liberec, Jablonec nad Nisou and Semily, in which were multiplied frog (Rana temporaria) and toad (Bufo bufo). On these localities I've watched a few environment variables, which I assume that may affect the successful development of amphibians from egg stage to metamorphosis. The success of development, I determined by counting congeries in the spring and then finding the number of tadpoles in the tank survived the conversion. The results of multiple linear regression shows that the developmental stages of brown frog react negatively to the increasing altitude and increasing the number of eggs per unit area of the tank. On the contrary, they thrive better in larger, at least partially shaded tanks, which are subject to fluctuations in water level. For toad are suitable not very deep, partially shaded tanks, with a stable water level, vegetation and aquatic vegetation free shores. Also managed to find the eggs and tadpoles of toads react negatively to the...
Asthma In Children's Population and the Enviromental Factors In Selected Towns of the Czech Republic
Fiala, Josef ; Kazmarová, Helena (referee) ; Dzúrová, Dagmar (advisor)
The aim of this thesis is to give information about asthmatic disease, to evaluate the situation in Czech children's population and to analyze the impacts of selected environmental factors on the occurrence of the bronchial asthma in selected age group. In the first part of this thesis are the information about bronchial asthma. In the second part of this thesis are description of the data of selected children group and characteristics of the environment (the source of data was from Czech National Health Institute). There are verifications of the null hypotheses about the risk effect of the environmental factors on the occurrence of the bronchial asthma among 5-years-old children in selected towns of the Czech Republic. The selected towns are České Budějovice, Hodonín, Hradec Králové, Jablonec nad Nisou, Jihlava, Karviná, Kladno, Mělník, Most, Olomouc, Sokolov, Ústí nad Labem, Ústí nad Orlicí and Žďár nad Sázavou.
Analysis of selected factors affecting occurrence of Chalara fraxinea in the environment.
Havrdová, Ludmila ; Šrůtka, Petr (advisor) ; Jaroslava, Jaroslava (referee)
Extensive investigation of ash dieback impact on different rural vegetation types (solitaires, scattered plantations, riparian stands, scree- and ash-alder alluvial forests) was performed in the Lusatian Mts. (the Czech Republic) between 2011 and 2013. The rate of ash dieback and 27 environmental variables were investigated in 80 research plots with a total of 1045 evaluated trees. The developed model (GLM) explained ca 27% of the disease variability. Particular models for each vegetation type importantly differed from each other and explained 28--46% of the disease variability. The variables that positively affected the disease impact included the host crown area, ash area and rate of ash in the stands, tree layer area, canopy closure, north aspect, shrub and herbaceous layer canopy, vertical heterogeneity and standard deviation of TPI. Tree height, the distance and damage of the nearest host as well as the water source distance, slope and its standard deviation affected it negatively. The coincidental attack of the trees by Armillaria sp. and Hylesinus fraxini positively affected the disease progress, whereas the presence of Nectria sp. and Aceria fraxinivorus conclusively decreased progress, most likely via the induction of secondary metabolites. The highly conclusive regression of ash dieback on the number of days with an air humidity of >95% between 6--11 a.m. in the main period of ascospore spread was identified. Because the air humidity near the ground was highly affected by local factors, a GLM model explaining the variability of air humidity with that of investigated factors was developed. This model explained 77% of the variability attributed to air humidity, local factors (TPI and SD of TPI, aspect, slope, altitude, distance from open water, tree and shrub layers canopy, tree stand height, etc.) greatly affected the disease impact related to air humidity. The landscape form was identified as a factor (most likely via air humidity) that affects the impact of the disease -- for example, the stands on mountain tops and slopes were less affected than the stands in valleys. The vegetation types highly differed in the disease extent. In general, the solitaires and scree forests were significantly less damaged than mixed ash-alder forests and riparian stands. The smaller stands were less affected than the more extended, the stands enclosed in canopy of other forests were less damaged than comparable vegetation in open landscapes and stands with higher humidity (riparian stands and mixed ash-alder forests) were more damaged than those without water. The outcome clearly supports the possibility of development and usefulness of appropriate forest and landscape management of the disease.

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