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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Kvantilové křivky / Quantile curves

Michl, Marek January 2017 (has links)
Modeling of quantile curves is a common problem across various fields in today's practice. The topic of this thesis is estimating quantile curves in case of two-sample gradual change. That is, when a relationship between two continuous variables in two samples is of interest, where the relationship is the same for both samples until a certain value of the explanatory variable. From that point on the relationship can differ. The result of this thesis is a procedure for estimating quantile curves, which fulfill this concept. 1
152

Biodegradation studies of recycled vegetable oils, surface-active agents, and condensing wastewaters

Prokkola, H. (Hanna) 10 November 2015 (has links)
Abstract Biodegradation is an aerobic or anaerobic degradation reaction where bacteria use organic materials as an energy source. In the aerobic biodegradation reaction, bacteria need oxygen as an electron acceptor, whereas an anaerobic reaction takes place in the absence of oxygen. Compounds degrade totally or partially, and produce simple inorganic species, such as CO2, CH4, NH3, NO3−, and H2O, as well as by-products that may be non-biodegradable and/or toxic. In this thesis, the biodegradability of recycled vegetable oils, surface-active agents, and condensing waters from the process of wood drying were studied using the manometric respirometric BOD OxiTop method. The biodegradation of organic compounds was measured under the standard conditions (OECD 301F), and also in other matrices, such as different waters and soils. These are very different environments with respect to the biodegradation reaction in nature. The main differences in waters and soils are their organic and inorganic nutrient contents, bacteria strains, and temperatures. The BOD OxiTop method is based on automatic pressure detection in a closed reactor vessel. Oxygen is consumed and carbon dioxide is formed in the aerobic reaction. The pressure decrease is detected after the carbon dioxide is adsorbed into a NaOH pellet or solution. The pressure change is dependent on oxygen consumption. The degree of biodegradation is calculated from the BOD value of the sample. The studied recycled vegetable oils were found to be 60–83% biodegradable, and the added surface-active agent did not affect their biodegradation. Biodegradation of tall oil soaps was also examined in sand, topsoil, groundwater, and surface water, as well as under OECD 301F standard conditions. Tall oil soaps were proven to be 50–85% biodegradable. Concrete solvent agent (CSA) was also proven to be 78–83% biodegradable under standard conditions. Another detergent, cetyltrimethylammonium bromide (CTAB), was found to be toxic, whereas Triton X-100 biodegraded by only 6% in solution. Biodegradation of the soil matrix was found to be enhanced with added surface-active agents. This can be explained by better wetting of small pores with surface-active agents, as compared to the behavior of pure water. The biodegradation of the matrix occurred even with toxic surface-active agents. Organic pollutants of wastewaters from the process of wood drying were 25–61% biodegradable during a 28-day period, and were proven to be quite pure when considering the carbon content of the samples. Based on these results, the disposal into drainage of condensing waters from wood drying may be regarded as safe, which from an economical viewpoint is a very important conclusion. / Tiivistelmä Biohajoavuus on luonnollinen aerobinen tai anaerobinen hajoamisprosessi, jossa bakteerit käyttävät orgaanista materiaalia energian lähteenä. Aerobisessa reaktiossa bakteerit tarvitsevat happea elektronien vastaanottajaksi, kun taas anaerobinen reaktio tapahtuu hapettomissa olosuhteissa. Yhdisteet hajoavat joko täysin tai osittain sekä tuottavat yksinkertaisia epäorgaanisia yhdisteitä, kuten CO2, CH4, NH3, NO3− tai H2O. Reaktiossa voi myös muodostua sivutuotteita, jotka voivat olla biohajoamattomia ja/tai toksisia. Tässä työssä on tutkittu kierrätettyjen kasviöljyjen, pinta-aktiivisten aineiden sekä jätevesien sisältämien orgaanisen aineksien biohajoavuuksia käyttäen manometristä respirometristä BOD OxiTop-menetelmää. Biohajoavuutta mitattiin standardiolosuhteiden (OECD 301F) lisäksi muissakin olosuhteissa, kuten erilaisissa maissa ja vesissä. Nämä ovat kaikki hyvin erilaisia ympäristöjä luonnossa tapahtuville biohajoavuusreaktioille. Pääasialliset erot ovat sekä orgaanisten että epäorgaanisten ravinteiden määrässä, bakteerikannoissa ja lämpötilassa. BOD OxiTop-menetelmä perustuu automaattiseen paineen muutoksen havainnointiin suljetussa astiassa. Aerobisessa reaktiossa kuluu happea ja muodostuu hiilidioksidia, joka imeytetään NaOH-pelletteihin tai -liuokseen ja tästä muodostuu alipaine. Paineen muutokset muunnetaan hapenkulutuksen arvoiksi, joista lasketaan biohajoavuusaste. Tutkittujen kierrätettyjen kasviöljyjen biohajoavuusasteet vaihtelivat välillä 60–83 %, eikä lisätty pinta-aktiivinen aine vaikuttanut kyseisten ekoöljyjen biohajoavuuteen. Mäntysaippuoiden biohajoavuus tutkittiin standardiolosuhteiden lisäksi hiekassa, mullassa, pohjavedessä sekä pintavedessä. Niiden biohajoavuusasteet vaihtelivat välillä 50–85 %. Betoninpesuaineen biohajoavuusaste standardiolosuhteissa oli 78–83 %. Kahdesta tutkituista pinta-aktiivisista aineista setrimoniumbromidi (CTAB) oli myrkyllinen liuosolosuhteissa eikä täten biohajonnut ja Triton X-100 biohajosi vain 6 %. Pinta-aktiivisen aineen lisääminen maahan aiheutti matriisina käytetyn maan biohajoamisen. Tämä voitiin selittää siten, että pintajännityksen laskemisen jälkeen neste voi paremmin tunkeutua maan pieniin huokosiin ja näin tuoda hajoamatonta orgaanista ainesta ja uusia bakteereita biohajoavuuskäyttöön. Tämä ilmiö havaittiin myös myrkyllisen pinta-aktiivisen aineen lisäyksen jälkeen. Jätevesien sisältämät orgaaniset ainekset hajosivat 25–61 % 28 päivän aikana ja niiden havaittiin olevan hiilen määrän huomioon ottaen hyvin puhtaita. Tässä tutkimuksessa saatujen tulosten perusteella tutkitut puunkuivauksen kondenssivedet voidaan laskea viemäriin, mikä on erittäin tärkeä tulos ekologiselta ja taloudelliselta kannalta katsottuna.
153

Změny prahu tlakově-algické citlivosti svalu v závislosti na kloubní konfiguraci - centrované vs. decentrované postavení / Joint configuration changes pressure pain threshold-centered and decentered position

Jevič, Filip January 2011 (has links)
The term "joint centration" is recently perceived primarily in its biomechanical context. This paper suggests a possible neurophysiological point of view and examines the effect of centered or decentered position on pressure pain treshold (PPT) of three muscles (m. temporalis, m. tibialis anterior, m. interosseus dorsalis I) in sitting and lying position, researched on healthy volunteers. PPT was measured in four randomly ordered positions with 49 people (21 women, 28 men). Significantly higher PPT was detected in all three muscles (p=0,001; 0,0016; 0,00009). In percent the PPT change resembles some of studies working with therapeutical techniques (mobilization, joint manipulation, exercise). Influence of higher postural position (sitting compared to lying down) on PPT was not proved. Cenetered joint position increases the PPT of healthy young adults compared to decentered position. This newly proved fact opens further possibilities of conceiving the key physiotherapeutical notion of "joint centration".
154

Lewisův bod obratu jako hrozba pro čínskou ekonomiku? / Lewis turning point as a threat to the Chinese economy?

Merzová, Linda January 2013 (has links)
The diplomma thesis deals with the Lewis turning point and its impact on the Chinese economy. The work is divided into three main chapters. The first chapter explains the basic concept ,,Lewis turning point" and its position in the global context. Besides W. A. Lewis is also mentioned in a number of other authors dealing with growth theories. Here it is primarily determined whether China has reached the Lewis turning point, which is the impact of this point on the Chinese economy, the labor market and what follows the development of the Chinese economy after reaching this point. The third part is found a connection between Lewis turning point and university/higher education. Part of this chapter are the specifics, trends and especially the problems of the university system in China. The conclusion of this chapter is devoted to a turning point, and its impact on education.
155

Optimizing Sample Dissolution Methods of Low Water Soluble Intermediate Organic Compounds to Support Environmental Risk Assessment during Active Pharmaceutical Ingredient Manufacturing.

Mohammed, Warda January 2021 (has links)
This project focus on investigating the dissolution of low water-soluble intermediate organic compounds called active pharmaceutical ingredients (API) and organic substances that are manufactured by a pharmaceutical company, Cambrex Karlskoga in Sweden. Several dissolution methods were used and evaluated using methods including total organic carbon (TOC), chemical oxygen demand (COD), biochemical oxygen demand (BOD) and Microtox toxicity test. The selection of solvents were based on previous studies and specifications from the Swedish Institute of Standards, SIS.The performance of eight solvents for different organic substances were evaluated using the above mentioned methods. Solvents that are highly volatile and have low solubility in water were excluded. Therefore, dimethyl sulfoxide (DMSO), dimethylformamide (DMF) and Pluronic F-68, that had highest water solubility, low acute toxicity and not degradable by microorganisms, were further used to dissolve four organic substances. Furthermore, DMSO and DMF were then also used to dissolve four censored chemicals with addition of physical treatment and solvent mixtures (DMF:DMSO with ratio 1:2).Results from each method were discussed and statistical tests were also performed in order to compare different dissolution methods. In addition, quality control and quality assurance were made in order to ensure the quality of measured values from analytical methods. Four organic substances were dissolve in DMSO, DMF and Pluronic F-68 with dissolution ≥79% using six ratios of DMSO and DMF and five ratios of Pluronic F-68 which were analyzed using TOC. Physical treatment increased dissolution of two APIs with 40%. Using BOD, para-aminobenzonic acid (PABA) and 5-nitroisophthalic acid (5-NIPA) had values higher than the guideline values, which indicate high biodegradability of these organic substances. PABA, 5-NIPA and bupivacaine base were acute toxic where PABA showed EC50 values of 27.9 mg/L using DMSO and 36.0 mg/L using DMF, and EC50 values of 5-NIPA were 102 mg/L using DMSO and 84.0 mg/L using DMF, and bupivacaine base had EC50 value of 174 mg/L using solvent mixture (DMF:DMSO with ratio 1:2). With increasing amount of Pluronic F-68, 5-NIPA had increased values of EC50, thereby Pluronic F-68 was not appropriate to use.In conclusion, DMSO and DMF were most appropriate solvents to use in order to dissolve APIs and organic substances with analyte: DMSO ratio of 1:0.5 and analyte: DMF ratio of 1:0.25. In addition, physical treatment could be used in order to increase dissolution of the APIs.
156

Roštový kotel na spalování biomasy - 88 t/h; 9,6 MPa; 520 °C / Grate Biomass Boiler - 88 t/h; 9.6 MPa; 520 °C

Střecha, Josef January 2017 (has links)
This master's thesis deals with the design of stoker-fired boiler for combustion of biomass. The main points of work are stoichiometry calculation of combustion, determining the dew point of flue gas, calculation of losses, which ones serves for determination of boiler efficiency, dimension design and detail calculation of thermosetting surfaces. In the last chapter is numbered total balance and real thermal efficiency of boiler.
157

Vliv elektronového svazku na grafenové polem řízené tranzistory / Influence of electron beam on graphene field effect transistors

Mareček, David January 2017 (has links)
This diploma thesis deals with electrical conductivity of a graphene sample, preparation of a graphene field-effect transistor and his irradiation by electron beam. In the theoretical part of the thesis, we describe electronic properties of graphene, preparation of graphene by CVD and its transfer to Si substrate with SiO_2 layer. Experimental part of this thesis is focused on the preparation of a graphene field-effect transistor for use in UHV conditions. Futher describes electron beam scanning over the transistor and creation of current maps of tranzistor. In the last part, the thesis deals with influence of electron beam on transport properties of graphene layer and doping of graphene layer by electron beam.
158

Proměny architektonického prostoru 20. století Elementární geometrické koncepce tvorby moderního arch.prostoru / The metamorphosis of the architectural space of 20th. century elementary geometric conception of forming of modern architectural space

Svoboda, Lukáš Unknown Date (has links)
Dissertation aims to clearly document the whole unique wide range of issues relating to the architectural space, including its historical development. Thesis should remind the fundamental questions we have to ask working with space and basic ways to access this phenomenon and to draw attention to their importance for the formulation of the overall architectural concept. The fundamental geometric concepts should be clarified on the theoretical basis, which are currently used for the expression of diverse concepts, or geometry, which are themselves fundamental concept of architectural design. They are concepts that significantly extend the range of expression of architecture.
159

Podnikatelský záměr –Vytvoření nového inovativního softwareového produktu / Business Plan - Creating of a new innovative software product

Jakůbek, Aleš January 2018 (has links)
This diploma thesis deals with the business plan, which is the development of a new product of already established company. For good processing of the business plan, the findings are written in the theoretical part of the thesis. These include the data processed in the analytical part and also in draft part, which should reflect the current economic situation of the company and results in possible scenarios of the project.
160

Analýza výhledových poměrů z užitkových vozidel / Analysis of the Field of View from Commercial Vehicles

Marek, Tomáš January 2018 (has links)
Analysis of the field of view from commercial vehicles is very important issue. Because driver’s field of view is main part of active safety. When some traffic accident happens, it must be investigated. The question is, was the driver able to see that object? It’s very different and important if driver didn’t see that object or couldn’t see it. In the thesis are described norms which contains information about driver’s position on driving seat and position his eyes, information about differences between binocular and ambinocular field of view. In the thesis are regulations about rearview and rearview mirrors. The thesis contains elements of vehicle equipment for improvement field of view. The thesis is about possibilities, how measure the field of view from commercial vehicles. The thesis contains few methods for measurements driver’s field of view and theirs results. Objective of the thesis is to take experiences from measured tests and use them for invention and description own method of measuring driver’s field of view from commercial vehicles, which leads to improvement. Then use the method for measurements and comparations few commercial vehicles. Which are dimensionally more bigger and have bigger blind spots than personal vehicles.

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