National Repository of Grey Literature 24,337 records found  previous11 - 20nextend  jump to record: Search took 0.76 seconds. 

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.

Lifelong Education as a Part of the Social System
Neckařová, Jana ; Šrédl, Karel (advisor) ; Hana, Hana (referee)
The diploma thesis discusses about education of adult population, while pointing out necessity of education in any age. This thesis explain importance of education of the adult population, mention forms and possible methods which are used in this type of education the most. Besides the theoretical outcome there is practical aspect included as well in form of questionnaires. Investigation in form of research was focused directly on employees, who as well as on employers whose employees attended the program. In summary both parties consider adulthood gained knowledge as a great benefit to employee as well as employer. In any case, people with higher level of education have better chances of getting a possible job than those with no or low level of education.

Frequency stabilized semiconductor laser source for high-resolution interferometry
Řeřucha, Šimon ; Hucl, Václav ; Holá, Miroslava ; Čížek, Martin ; Pham, Minh Tuan ; Pravdová, Lenka ; Lazar, Josef ; Číp, Ondřej
We have assembled an experimental iodine stabilized Distributed Bragg Reflector (DBR) diode based laser system lasing at a wavelength that is in a close proximity to the wavelength of a stabilized He-Ne lasers traditionally used for metrological applications (λ=632.9 nm in vacuum). The aim was to verify whether such a system could be used as an alternative to the He-Ne laser while yielding wider optical frequency tuning range, higher output power and high frequency modulation capability. We have measured the basic characteristics of the laser source and then we have compared the performance of the laser system with that of a traditional frequency stabilized He-Ne laser with a series of experimental arrangements similar to those usually found in laser interferometry and displacement metrology applications. The results indicate that DBR diode laser system provides a good laser source for applications in dimensional (nano)metrology since it provides more output power and advanced tunability options than stabilized He-Ne lasers while maintaining fundamental requirements such as the frequency stability, coherence length and also a defined traceability.\n\n

Noise, Transport and Structural Properties of High Energy Radiation Detectors Based on CdTe
Šik, Ondřej ; Lazar, Josef (referee) ; Navrátil, Vladislav (referee) ; Grmela, Lubomír (advisor)
Poptávka ze strany vesmírného výzkumu, zdravotnictví a bezpečnostního průmyslu způsobila v posledních letech zvýšený zájem o vývoj materiálů pro detekci a zobrazování vysokoenergetického záření. CdTe a jeho slitina CdZnTe. jsou polovodiče umožnují detekci záření o energiích v rozsahu 10 keV až 500 keV. Šířka zakázaného pásma u CdTe / CdZnTe je 1.46 -1.6 eV, což umožňuje produkci krystalů o vysoké rezistivitě (10^10-10^11 cm), která je dostačující pro použití CdTe / CdZnTe při pokojové teplotě. V mé práci byly zkoumány detektory CdTe/CdZnTe v různých stádiích jejich poruchovosti. Byly použity velmi kvalitní spektroskopické detektory, materiál s nižší rezistivitou a výraznou polarizací, detektory s asymetrií elektrických parametrů kontaktů a teplotně degenerované vzorky. Z výsledků analýzy nízkofrekvenčního šumu je patrný obecný závěr, že zvýšená koncentrace defektů způsobí změnu povahy původně monotónního spektra typu 1/f na spektrum s výrazným vlivem generačně-rekombinačních procesů. Další výrazná vlastnost degenerovaných detektorů a detektorů nižší kvality je nárůst spektrální hustoty šumu typu 1/f se vzrůstajícím napájecím napětí se směrnicí výrazně vyšší než 2. Strukturální a chemické analýzy poukázaly, že teplotní generace detektorů způsobuje difuzi kovu použitého při kontaktování a stopových prvků hlouběji do objemu krystalu. Část mé práce je věnována modifikaci povrchu svazkem argonových iontů a jejímu vlivu na chemické složení a morfologii povrchu.

Subspace Modeling of Prosodic Features for Speaker Verification
Kockmann, Marcel ; Kenny, Patrick (referee) ; Nöth, Elmar (referee) ; Černocký, Jan (advisor)
Předložená disertační práce se zabývá ověřováním mluvčího pomocí prozodických příznaků zahrnujících hodnoty základního tónu, energie a délek řečových úseků. Studovali jsme dvě rozdílné techniky pro parametrizaci: první vede k dobře definované sadě menšího počtu příznaků, druhá k vysoko-dimenzionální sadě heterogenních prozodických příznaků. První část práce se věnuje vývoji příznaků reprezentujících prozodické kontury, zde jsme vyvinuli a ověřili několik modelovacích technik, s důrazem na modelování v reprezentativních podprostorech. Druhá část práce se zaměřuje na nové pod-prostorové modelovací techniky pro heterogenní prozodické parametry s velkou dimenzionalitou. Model je teoreticky odvozen a experimentálně ověřen na oficiálních datech z NIST evaluací ověřování mluvčího (NIST Speaker Recognition Evaluation). Ve srovnání s ostatními současnými prozodickými jsme dosáhli podstatně lepších výsledků. Na konci práce presentujeme také novou techniku pro elegantní kombinaci dvou prozodických systémů. Tato technika může být použita rovněž pro fúzi prozodického systému se standardním přesným cepstrálním systémem, což vede k dalšímu podstatnému zvýšení úspěšnosti verifikace.  

The development of the crime on credits in the South Bohemia before 2014
BUŠKOVÁ, Tereza
The aim of this study is to analyze the development of committing a credit fraud offence under § 211 of the Act. no. 40/2009 Coll., the Penal Code (particularly the development of this crime and the development of the amount of the damage) and consequent comparing the selected macroeconomic indicators development in the period 2005-2014 in the region of South Bohemia. In this work secondary data analysis methods were used. Statistical data obtained from the South Bohemian branch of the Czech Statistical Office and statistical data from Crime Police of the Czech Republic was used as the source. The data evaluating the amount of detected cases of this crime committed by the offenders in the Region South Bohemia, according to the region where the fraud was commited, was analyzed. The analyzed file was 5,713 offenses and 4,219 offenders. The defined set was divided into seven parts (districts), according to the local jurisdiction of the territorial departments of the Czech Police. The observed data was compared with selected macroeconomic indicators. From the results it can be concluded that the highest rate of loan fraud offence (calculated per 1,000 inhabitants) is in the district Stra-konice. Conversely, the lowest crime in the same period is in the district Jindřichův Hradec. This work also re-vealed that the development of macroeconomic indicators has no effect on the development of this crime. In conclusion, it is recommended to promote economic education at primary and secondary schools, thus improving the financial literacy of the population. Furthermore, we can recommend the consistent use of, the Central Credit Register, which is already available, as well as supporting of changes in the legislation, so that the providers have an obligation to investigate the credit applicants more and make the offenders of this crime discouraged by higher penalties imposed for credit fraud.

Consumption of fiber in old age
ŠÁLEK, Jan
The theme of this bachelor thesis is the Consumption of fiber in the old age (seniors). Formerly, the dietary fiber was considered unnecessarily burdensome for human organism. Later, it was found that it has a relatively large impact on human health, especially by serving as a prebiotic for symbiotic bacteria inhabiting the gastrointestinal tract. There is still prevailing opinion that roughage divides into a soluble and insoluble, despite that some types of fiber cannot be definitely classified and placed into any of these groups because they have characteristics of both of them. The daily recommended dose is 30 g. The qualitative research was used for elaboration of the practical part. The first goal was to find out how much fiber seniors consume. The second aim was to compare the consumption of fiber among elderly people living alone and the elderly living in retirement homes built for them. The research group, at the first research question, consists of 20 seniors from the Southern Region aged over 65 years. The research group, at the second research question, consists of five retirement homes from the whole Czech Republic. All respondents were given a record sheet for one week, and instructions on how to fill it. Acquired menus were subsequently re-calculated through the program "Nutriservis Professional". The results show higher consumption of fiber than the average in the Czech Republic, but there is still almost a half missing to get the recommended daily dose. There was observed BMI and its impact on the consumption of fiber. No significant effect was found, because overweight had all interviewees except one respondent. The financial limit is visible for evaluated diet of homes for the elderly, therefore, there are no whole grain products, vegetables and almost no fruit. Despite these limitations, the average consumption of fiber is almost equal to elderly people living alone. In conclusion, there is a proposition how to, despite the low funds, increase the intake of roughage, and avoid or, at least, reduce the problems associated with its low consumption. Recommendations for respondents are individual and given under each evaluation.

Card of Cryptosporidium infections by humans and animals
BLÁHOVEC, Ondřej
The representatives of the Cryptosporidium genus are one of the causes of gastrointestinal tract diseases in humans and animals. In animals the host may even be a respiratory apparatus. The disease is called cryptosproridiosis. In majority of cases this infection can bypass without any major problems, but in immunosuppressed individuals it can cause serious health problems. Cryptosporidium has a monoxenous development cycle, which basically means that the entire development takes place in a single host. Exogenous stage is represented by oocysts, which are in case of a gastrointestinal disease excreted in faeces. In case of a respiratory disease the oocysts make they way out via respiratory and nasal secretions. This leads to contamination of the environment or water. In general, it is expected that Cryptosporidium isolates, which are present in one class of vertebrates, are not infectious to a non-specific host from other classes. It is also expected that cryptosporidia have low host specificity. But this does not exclude that some kinds have gradually extended its specificity to more species. It is also apparent that cryptosporidium infections are common in animals that inhabit the external environment, so even a human can be endangered by this zoonosis, although the incidence in the Czech Republic is low. The reason for the low numbers may as well be that parasitological examination is not performed very often, so the estimated prevalence in the population is probably much higher. Therefore to reveal the originator of this disease it would be appropriate to perform a parasitological examination in persons who are in contact with animals, this way the cryptosporidium infection would be excluded or proven.

Vliv teploty vody a intenzity světla na raný vývoj sumečka afrického v komerčním chovu
PROKEŠOVÁ, Markéta
The successful production of quality early fish stages is crucial for artificial rearing fish species. Nevertheless, it is quite a problematic process, because fish as poikilothermic organisms are highly sensitive to various environmental conditions. Moreover, both fish embryos and larvae are more affected by biotic and abiotic factors (such as predation, stocking density, temperature, light, pH, salinity, oxygen saturation, feeding availability, or their interactions) than older juveniles or adults. Most fish processes such as reproduction, metabolism, survival, development and growth can be considerably (positively, negatively or not) influenced by these conditions. Therefore, it is important to understand their impacts on fish stages during embryonic, larval, juvenile, adult, and eventually the senescent period. Then, following the application of new knowledge to the practise, especially species- and age-specific optimal conditions, should result in higher survival, better growth rate, well developed fish without deformities and lower cannibalism. The objectives of the present thesis were to assess the effect of water temperature and light intensity on the early development (embryonic and larval period) of African sharptooth catfish as a perspective fish species for freshwater intensive aquaculture. Due to its great characteristics (for instance fast growth, ability to breathe atmospheric air, rearing at high stocking density) this species can meaningfully contribute to the global aquaculture production which is expected to rise in the coming years. However, there are still some difficulties in the early rearing African sharptooth catfish regarding the cannibalism, feeding, survival and necessity of detailed information about the effects of some abiotic factors and their interactions.

Nové postupy biomonitoringu cizorodých látek ve vodním prostředí
ČERVENÝ, Daniel
Within the presented work, several approaches of biomonitoring were studied. A well-established method for human health risk assessment was applied to evaluate the quality of fish from open waters in the Czech Republic. As this work is targeted on sport fishermen, who frequently consume their own catches, besides the publication in scientific journal, a brochure with results of this study was distributed via the Czech Fishing Union. Health risks for consumers related to the consumption of wild fish were found strongly species and locality dependent. As there is no risks related with the consumption of carp (Cyprinus carpio) at all investigated sites, frequent consumption of predatory fish should be avoided at some fishing grounds. The use of passive samplers has become more and more attractive in the last two decades. As these devices are able to mimic the biological uptake of chemicals, their potential for replacing fish as bioindicators in routine biomonitoring programmes is evident. In our study, the comparison between analysis of fish tissues and POCIS extracts from selected sampling sites confirms this idea about interchangeability of these indicators in the case of PFASs as target pollutants. Moreover, no metabolic transformation of contaminants present in water take place in passive samplers contrary to living organisms, thus these reflect the actual contamination at the locality more precisely. The use of passive samplers completely fulfils the internationally accepted principles of Replacement, Reduction, Refinement (the three R´s). Another promising approach using YOY fish as bioindicators was evaluated within the present study. Multispecies samples of YOY fish homogenate was found as a better indicator for wide range of pollutants than muscle tissue of adult fish within one species from the same locality. As all inner organs and tissues are presented in analysed samples, more target pollutants in higher concentrations are detected compared to the muscle of adults. Besides the higher sensitivity in pollutants detection and quantification, practical and economic benefits are of concern in the case of the YOY fish approach. The YOY fish approach also particularly fulfil the three R´s strategy, as sampling of this age group of fish has a smaller impact on the environment than the sampling of adults. In case of mercury, that was found as a limiting contaminant for the consumption of fish from open waters in the Czech Republic, a nonlethal method of finclips sampling can be used for the monitoring of this compound in aquatic environments. Besides the monitoring, our optimised method for the estimation of muscle tissue concentrations could be used for human health risk assessment as well. The difference between real muscle concentrations and concentrations estimated using our method differs less than 10% in most of the investigated localities. Benthic organisms are an important part of the food web in aquatic environments, but insufficient information about its contamination is available. In another study included in this thesis, first evidence about bioaccumulation of certain pharmaceuticals in benthic organisms was described. Although, pharmaceuticals are generally considered to be not accumulative in organisms, our study proved that certain pharmaceuticals have bioaccumulation potential. From this finding, it is evident that not only the concentrations of pharmaceutical dissolved in water but also the diet represents an important exposure pathway of contamination by these compounds for organisms (fish) inhabiting aquatic environments.