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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.
141

Cytochrome P450 2E1/Nickel-Poly(propylene imine) dendrimeric nanobiosensor for pyrazinamide - A first line TB Drug

Zosiwe, Mlandeli Siphelele Ernest January 2015 (has links)
>Magister Scientiae - MSc / The tuberculosis (TB) disease to this day remains one of the world’s prominent killerdiseases. Pyrazinamide (PZA) is one of the most commonly prescribed anti- tuberculosis (anti-TB) drugs due to its ability to significantly shorten the TB treatment period from the former nine months to the current six months duration. However, excess PZA in the body causes hepatotoxicity and damages the liver. This hepatotoxicity, together with the resistance of the bacteria to treatment drugs, poor medication and inappropriate dosing, greatly contribute to the high incidents of TB deaths and diseases that are due to side effects (such as liver damage). This brings about the calls for alternative methods for ensuring reliable dosing of the drug, which will be specific from person to person due to inter-individual differences in drug metabolism. A novel biosensor system for monitoring the metabolism of PZA was prepared with a Ni-PPI-PPy star copolymer and cytochrome P450 2E1 (CYP2E1) deposited onto a platinum electrode. The nanobiosensor system exhibited enhanced electro-activity that is attributed to the catalytic effect of the incorporated star copolymer. The biosensor had a sensitivity of 0.142 µA.nM-1, and a dynamic linear range (DLR) of 0.01 nM-0.12 nM (1.231 – 7.386 ng/L PZA). The limit of detection of the biosensor was found to be 0.00114 nM (0.14 ng/L) PZA. From the HPLC peakconcentration (Cmax) of PZA determined 2 h after drug intake is 2.79 – 3.22 ng.L-1,which is very detectable with the nanobiosensor as it falls within the dynamic linear range.
142

Stability Analysis of Non-overflow Section of Concrete Gravity Dams : A Longtan Dam case study

Johansson, Lukas, Valtersson, Dan January 2018 (has links)
No description available.
143

Systém řízení pohledávek / The management system of receivables

Lukešová, Kristýna January 2016 (has links)
The thesis on The System of Management of Receivables is applied on a company which deals with past due receivables. In the theoretical part, there is explanation of terms connected with this subject: origination, expiry and aspects from which can perceive the receivables. In the chapter the system of management of receivables there is a description of evaluation of customers, contractual conditions, hedging as well as the recovery process. In the practical part, the company XYZ is introduced, their basic economic indicators are described including financial analyses for years 2012 to 2014. Furthermore, this part contains a sector analysis carried out in order to assess the risk level of the sector related to the development of past due receivables. Last but not least we examine an analysis of receivables and liabilities following the preceding years and clarify the existing system of management of receivables. The objective is to sum up information and results from analyses, internal documents and questioning in form of interviews in order to assess the current status of the company. The result of this thesis is a proposal for improvement of the credit management, a comparison and a calculation of costs of possible measures.
144

ESTIMATION OF DOWN-DIP LIMIT OF THE TONGA SEISMOGENIC ZONE FROM OCEAN BOTTOM SEISMOGRAPH DATA

Dande, Suresh 01 August 2013 (has links)
The largest earthquakes occur along the subduction thrust interface known as the seismogenic zone. Until recently, erosive margins like Tonga and Honshu have been thought to be unable to support earthquakes with magnitudes higher than 8.5. However, Mw 9, 2011 Tohoku-oki earthquake in Honshu requires a reevaluation of this notion. The seismic potential of Tonga is likely affected by the vertical spatial extent of the up-dip and down-dip limits, which confines the seismogenic zone. The larger the area of the seismogenic zone, the higher the potential for larger earthquakes. Some models suggest that down-dip limit coincides with the fore-arc Moho while others suggest that they are coincident with thermally controlled mineralogical phase changes during slab descent. Tonga is an ideal place to discriminate between these possibilities, as the incoming Pacific plate is cold and thick with rapid convergence, extending cool isotherms deep into the system. In contrast, the fore-arc Moho is only ~16 km deep. This study tests the hypothesis that the down-dip limit of the Tonga seismogenic zone coincides with the fore-arc Moho and thus ceases the seismicity by initiating a stable sliding between the mantle and the subducting crust. We determine the depth of the down-dip limit in Tonga by mapping the distribution of earthquakes recorded for a six-month period from January 1, 2010 to June 30, 2010 by a deployment of ocean bottom seismographs above the Tonga subduction zone. The earthquakes are located by a combination of grid-search method and least-square inversion of the observed arrival times. We identified a down-dip limit at a minimum depth of about 40 km below the sea level suggesting that the hypothesis is failed. Therefore, the commonly held idea that down-dip limit is coincides with the fore-arc Moho is not true in the Tonga case. It is likely controlled by the degree of serpentinization in the mantle wedge controlling the transition from stick-slip to stable sliding.
145

Motives of Log Schemes

Howell, Nicholas 06 September 2017 (has links)
This thesis introduces two notions of motive associated to a log scheme. We introduce a category of log motives à la Voevodsky, and prove that the embedding of Voevodsky motives is an equivalence, in particular proving that any homotopy-invariant cohomology theory of schemes extends uniquely to log schemes. In the case of a log smooth degeneration, we give an explicit construction of the motivic Albanese of the degeneration, and show that the Hodge realization of this construction gives the Albanese of the limit Hodge structure.
146

Dynamic equilibrium in limit order markets: analysis of depth disclosure and lit fragmentation

Orellana Alarcón, Rodrigo Ignacio January 2016 (has links)
Magíster en Ciencias de la Ingeniería, Mención Matemáticas Aplicadas / Ingeniero Civil Matemático / Se desarrolla un modelo dinámico a tiempo contínuo que permite el comercio de múltiples mercados financieros interconectados, organizados como limit order markets, en el cual agentes endógenamente toman decisiones óptimas para maximizar el valor esperado de sus ganacias. Los agentes toman sus decisiones considerando incentivos propios, condiciones de mercado, potenciales decisiones de negociación futuras y diferentes estrategias adoptadas por otros agentes. Se concentra el estudio al análisis de divulgación de profundidad y la fragmentación en el contexto de múltiples mercados. Se prueban tres escenarios principales: (i) un único mercado Transparente, (ii) un único mercado Opaco y (iii) un mercado múltiple interconectado entre una bolsa Transparente y una Opaca que comercian el mismo activo. Los resultados principales indican que, en el contexto de un único mercado, la divulgación de profundidad genera una competencia que incrementa el suministro de liquidez y, en consecuencia, reduce el spread, el ruido de mercado e incrementa la profundidad en los precios más competitivos y en el volumen total del libro. Los agentes con una valoración privada absoluta positiva del activo incrementan sus ganancias a costa de los agentes sin valoración privada, al disminuir sus costos de espera y aumentar sus ganancias por transacción. Estos beneficios son amplificados en el contexto de múltiples mercados debido a las restricciones para transar que generan una competencia más agresiva. Se encuentra que hay un flujo de liquidez hacia la componente Transparente debido a los agentes multi mercados proveedores de liquidez, lo cual reduce el spread e incrementa las profundidades. Para mantenerse atractivos, los agentes en la Bolsa Opaca también entran en competencia, lo cual reduce el spread y ruido de mercado en esta bolsa de similar manera. Los agentes multi mercados demandantes de liquidez son los que presentan el mejor rendimiento de todos, principalmente al reducir significativamente los tiempos de sus ejecuciones. / We develop a dynamic model in continuous time to simulate multi markets trading. Traders make endogenously sequential optimal decision to maximize their expected payoffs across different limit order markets, taking into account intrinsic incentives, markets conditions, potential future trading decisions and different strategies adopted by other agents. We focus our study in depth disclosure and lit fragmentation, and test three main scenarios: (i) a single Lit Market, (ii) a single Opaque Market and (iii) Multi Markets interconnected with both Lit and Opaque venues trading a single common asset. Our main results indicate that, in a single market environment, depth disclosure generates a competition that increments liquidity supply and as a consequence, reduces spread, microstructure noise and increases depth at best quotes and total depth of the book. Agents with a positive absolute private valuation of the asset increases their benefits at the expense of agents without a private valuation, by decreasing their waiting costs and increasing their money transfer. These benefits are amplified in a multi market environment due to trading restrictions that generates more aggressive competition. We find a liquidity flow to the Lit venue given by multi market liquidity suppliers, that reduces the spread and increases depths. To stay in competence agents in the Opaque Venue enter the competition as well, reducing spread and microstructure noise in that exchange too. Multi market liquidity demanders with the possibility to trade in both venues have the best performance of all agents, due to a significant reduction in their execution time.
147

Sledování, vyhodnocení a porovnání obsahu nitrátů v zelenině distribuované v obchodní síti vybrané oblasti ČR a přilehlé příhraniční oblasti Rakouska / Monitoring, evaluation and comparison of a nitrate content in vegetables distributed in a network of markets in selected area in the Czech Republic and adjacent regions of Austria

RŮŽEK, Marek January 2013 (has links)
The main aim of this study was to monitor and evaluate nitrate contents in vegetables, offered in the network of markets, from anti-nutritive point of view. The nitrate content was monitored in common vegetable types in the course of a year. The selected supermarkets were used as the source of samples. The ion-selective electrode measurement method was used to set the nitrate content. The analysed samples were provided in Billa markets in Jindřichův Hradec and in Heidenreichstein in Austria. In total 149 samples were analysed, 71 were provided in the Czech markets and 78 in Austria. The leaf and root vegetables were tested, especially lettuce, iceberg lettuce, a carrot, a parsley and a radish. The lowest measured value 21 mg NO3-.kg-1 was taken from the parsley from the Czech Republic. The highest nitrate content was detected in the lettuce also originated from the Czech production and reached 5200 mg NO3-.kg-1. In the final comparison with the neighbouring Austria, the Czech samples have shown, except for the carrot, higher nitrate contents.
148

Charge density waves and superconductivity in U6Fe

Whitley, William George January 2016 (has links)
U6Fe has the highest superconducting transition temperature TSC ~ 4 K out of all of the U-based compounds. Unusually, the Pauli limit (1:84TSC = 7:36 T) is less than the observed critical field for both the a and c axes in this tetragonal material. Neither Pauli or usual BCS orbital limit is apparently respected. In order to explain why superconductivity exceeds the Pauli limit, it must be considered that either the superconducting state is unaffected by paramagnetic effects, or there is a large amount of spin-orbit scattering. Superconductivity is in the dirty limit for typical samples of U6Fe, which means that the latter cannot be precluded. Another unusual property of the superconducting state of U6Fe is that TSC has a positive dependence on the applied pressure P, for P < 4 kbar. This combined with other subtle signals in various measurements have led to the suggestion that a Charge Density Wave (CDW) state may exist in U6Fe below 110 K. The CDW state is typically favoured by materials with low-dimensional structural features such as chains of atoms. Such materials, if superconductors, are also candidates to exhibit the sought-after Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state, an unusual state in which the superconducting order parameter is modulated in real space. The FFLO is expected to be suppressed except in clean, Pauli limited materials. Therefore if U6Fe can be produced at high enough quality to bring the superconducting state into the clean limit, it would be a potential candidate for an FFLO state. Part of this project discusses apparatus and techniques applied with the goal of producing such quality samples of U6Fe. We have succeeded in the application of the Solid State Electrotransport (SSE) method to purifying samples, and have been able to replicate the highest Residual Resistivity Ratios (RRRs) achieved (~9, compared to 4 for typical samples), but for single crystals instead of the polycrystals produced in the past. In parallel with the progress made towards higher quality samples of U6Fe, a new X-ray scanner has been developed for grain mapping of samples. This has found application in the course of our synthesis studies. The best quality samples have been studied by X-ray diffraction on the XMaS beamline at the ESRF in Grenoble, France. Below TCDW ~ 10 K, satellites at (δH; δK; 0) = (±0:11;±0:11; 0) were observed that confirm a CDW state, albeit at much lower temperatures than anticipated. By examination of systematic satellite absences we have determined that the displacement vector → u is perpendicular to the modulation direction in k-space. Additionally it has been found that the symmetry of the lattice below TCDW is reduced from that of the room temperature I4=mcm structure. The appearance of additional Bragg peaks below ~110 K during these experiments were later cast into doubt by multiple scattering. We have, however, detected a signal in the form of a jump at ~110 K in specific heat measurements of our samples. These measurements also show a kink near to TCDW. We have additionally extended the investigation of the effect of pressure on the superconducting state. The maximum of TSC is confirmed in our samples, and the subsequent suppression of TSC and Hc2 is investigated up to 8 GPa. We have analysed our Hc2(T) curves at different pressures under a simple two-band model that fits the observed trends well and suggest that at the highest pressures U6Fe is approaching even more unusually enhanced Hc2 values.
149

Limites e derivadas: uma abordagem para o ensino médio / Limits and derivatives: an approach to high school

Alves, Anderson Rafael 19 February 2018 (has links)
Submitted by ANDERSON RAFAEL ALVES null (andersonalves02@yahoo.com.br) on 2018-03-01T22:07:19Z No. of bitstreams: 1 Dissertação de Mestrado_Limites e Derivadas Uma abordagem para o Ensino Médio_Anderson Rafael Alves.pdf: 3324802 bytes, checksum: 0140974ce85a7cb7cb712209d9717277 (MD5) / Rejected by Maria Marlene Zaniboni null (zaniboni@bauru.unesp.br), reason: Solicitamos que realize correções na submissão seguindo as orientações abaixo: 1) FALTA ATA DA DEFESA - Inserir a Ata da Defesa após a ficha catalográfica. Agradecemos a compreensão. on 2018-03-02T17:57:29Z (GMT) / Submitted by ANDERSON RAFAEL ALVES null (andersonalves02@yahoo.com.br) on 2018-03-02T22:12:20Z No. of bitstreams: 1 Dissertação de Mestrado_Anderson Rafael Alves.pdf: 3183005 bytes, checksum: dd3a546bd4060a939884307089ec4870 (MD5) / Approved for entry into archive by Maria Marlene Zaniboni null (zaniboni@bauru.unesp.br) on 2018-03-05T16:11:12Z (GMT) No. of bitstreams: 1 alves_ar_me_bauru.pdf: 3183005 bytes, checksum: dd3a546bd4060a939884307089ec4870 (MD5) / Made available in DSpace on 2018-03-05T16:11:12Z (GMT). No. of bitstreams: 1 alves_ar_me_bauru.pdf: 3183005 bytes, checksum: dd3a546bd4060a939884307089ec4870 (MD5) Previous issue date: 2018-02-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Nesta dissertação abordamos os conceitos básicos de algumas funções elementares, limites, continuidade, além do conceito de derivada e sua aplicabilidade. Esse material apresenta uma formação sólida no que diz respeito aos pré-requistos necessários para um aluno do ensino médio ingressar num curso superior, em que o mesmo trabalhará, eventualmente, com aspectos relacionados ao Cálculo. Como uma proposta didática introduziremos os conceitos de limite e derivada utilizando ferramentas computacionais, neste, caso o software GeoGebra e apresentação em Beamer. / In this dissertation we will study the basic concepts of some elementary functions, limits, continuity, beyond the concept of derivative and it applicability. This material will present a solid training regarding the prerequisites required for a high school student to enter an upper course where he will eventually work with aspects related to Calculus. As a didactic proposal we will introduce the concepts of limits and derivative using computational tools, in this case GeoGebra software and Beamer presentation. / Não consta
150

Ciclos limite em sistemas de Filippov no plano / Limit cycles in planar Filippov system

Appis, Raul Felipe 02 March 2018 (has links)
Submitted by Raul Felipe Appis (raul_appis_2010@hotmail.com) on 2018-03-12T17:34:28Z No. of bitstreams: 1 textodissertacaoRAUL.pdf: 1347871 bytes, checksum: fed2ed8a808775f7df369369cac75556 (MD5) / Approved for entry into archive by Elza Mitiko Sato null (elzasato@ibilce.unesp.br) on 2018-03-13T18:24:11Z (GMT) No. of bitstreams: 1 appis_rf_me_sjrp.pdf: 1347871 bytes, checksum: fed2ed8a808775f7df369369cac75556 (MD5) / Made available in DSpace on 2018-03-13T18:24:11Z (GMT). No. of bitstreams: 1 appis_rf_me_sjrp.pdf: 1347871 bytes, checksum: fed2ed8a808775f7df369369cac75556 (MD5) Previous issue date: 2018-03-02 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Neste trabalho, nosso principal objetivo é estudar a existência e estabilidade de ciclos limite de costura em sistemas lineares planares de Filippov descontínuos obtidos pela agregação de dois sistemas lineares planares do tipo foco, e tendo apenas um ponto de equilíbrio. Ao usar uma forma normal adequada com cinco parâmetros, é realizado um estudo completo de algumas aplicações de Poincaré. São encontradas diferentes bifurcações que são responsáveis pelo aparecimento de ciclos limite de costura e regiões abertas no espaço de parâmetros com nenhum, um, dois e três ciclos limite de costura. / In this work our main aim is to study the existence and stability of crossing limit cycles in planar linear systems of discontinuous Filippov obtained by the aggregation of two planar linear systems of focus type, and having only one equilibrium point is considered. By using an adequate normal form with five parameters, a thorough study of some Poincar´e maps is performed. Different bifurcations which are responsible for the appearance of crossing limit cycles are detected and open regions in the parameters space with none, one, two and three crossing limit cycles are found. / 2015/24803-0

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