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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.
871

Isolation, Molecular Characterization Of Food-borne Drug Resistant Salmonella Spp. And Detection Of Class 1 Integrons

Avsaroglu, M. Dilek 01 September 2007 (has links) (PDF)
In this study, 59 epidemiologically unrelated Salmonella strains isolated from foods in T&uuml / rkiye and 49 Salmonella strains obtained from National Salmonella Reference Laboratories of Germany were analysed. For the characterization of strains, analyses such as serotyping, phage typing, antibiotyping and molecular biological characterization were done. The strains exhibited 17 different serotypes with S. Enteritidis serotype and PT21 phage type being the most prevalent in Turkish isolates. The highest antimicrobial resistance was observed against NAL for Turkish strains, whereas it was against SUL for strains from German origin. Molecular typing of all strains exhibited different plasmid profiles and PFGE patterns. There were 1-4 plasmids/profile for Turkish strains and 1-7 plasmids/profile for German strains. The PFGE patterns revealed 42 different subgroups, having two major clusters with 44,3% arbitrary homology. Among 72 resistant strains, the most prevalent resistance genotypes were observed as blatem-1 (%56, AMP resistance) / floR (%100, CHL and FFC resistance) / aphA1 (%100, KAN and NEO resistance) / tet(A) (%53, TET resistance) / aadA1 (%82, SPE and STR resistance) / sulI (%78, SUL resistance). The class I integron variable region analyses exhibited 700 bp (1 strain), 1000 bp (37 strain), 1200 bp (16 strain) and 1600 bp (3 strain) integrons.
872

Numerical Modeling Of Kizildere Geothermal Field

Ozkaya, Melike 01 December 2007 (has links) (PDF)
This research is dedicated to make a foreseeing of the future state of the Kizildere Geothermal Field in order to suggest acceptable solutions to the current problems. The non-isothermal mechanism of the geothermal field is simulated for the pressure and temperature variables. For this purpose, a finite element model (696 four-nodal elements with 750 nodes) of the field is formulated by considering the geological conditions and the present wells already drilled in the area. Then the model is calibrated to the field for the natural state by using appropriate physical properties, boundary and initial conditions. Comparison of the simulated and the observed pressures and temperatures has emphasized a very successful calibration study. After the calibration, response of the field to the production and injection for the period of 1984-2006 has been simulated by applying a history matching study. History matching runs have yielded very good correlations between the observed and the computed values of the pressure and temperature variables. The calibrated and history matched model has been applied to the field to simulate the future performance of the field for different production and injection scenarios. In the first scenario the field is simulated for the next 10-year production period keeping the on-going production conditions. Then, the influence of the production of two new wells has been investigated in two different scenarios. In the forth scenario, the effect of injection from one of the production wells has been simulated.
873

The Bilateral J-curve Of Turkey For Consumption, Capital And Intermediate Goods

Keskin, Gizem 01 July 2008 (has links) (PDF)
This study analyzes the J-curve effect for Turkey&rsquo / s bilateral trade with her three main trading partners / Germany, USA and Italy, for consumption, capital and intermediate goods. The bounds test is used to test for cointegration among the trade balance, the real bilateral exchange rate, the real domestic income and the real foreign income. The results show that the real exchange rate is not a significant determinant of trade in the short run. In the long run, it is significant only for trade with USA in consumption goods. Moreover, J-curve does not exist for Turkey&rsquo / s bilateral trade with Germany, USA, and Italy in consumption, capital and intermediate goods. The results support existence of a link between the bilateral trade balances and the real domestic income both in the short run and the long run.
874

Transformation Of The Morphology Of The Old City Of Sulaimaniyah (northern Iraq) From The Perspective Of Ownership Patterns

Amin, Hanaw Mohammed Taqi Mohammed 01 April 2010 (has links) (PDF)
The main objective of the thesis is to study the forces that built up the morphology of the old city of Sulaimaniyah and the reasons of its existence. It focuses on the morphological elements of property (ownership elements of streets, blocks and parcels) and their existence in spite of the impacts of modernism in the transformation of these elements. Modernity in Sulaimaniyah city affected the city in terms of the transformation of traditional life pattern and traditional structure into modern function. Modern function covers a new administrative system and new commercial functions. The city adapted itself to these new institutions. As a consequence, the power of state displayed itself in the form of building roads, and then the new larger and regular parcels were created to adapt new functions. Furthermore, the study aims to establish the historical evolution of the city starting from its foundation and the periods, which are signified by the introduction of modernism concepts. This study is analyzed through a morphological research depending on the physical elements as quantitative characteristics. It starts with an evolutionary plan analysis, which is a tool of morphological study and covers the old part of the city in macro scale, mezzo scale, and consequently, micro scale. The old fabric of Sulaimaniyah city as organic fabric faced the modernism&#039 / s impact gradually due to the construction of streets. In spite of this fact, preserving old fabric&#039 / s morphology behind the power of ownership pattern is still surviving. In this thesis, typology is another research method, which is used to analyze the evolution of the building fabric of the city in both functional and formal configuration. In addition, a comparison of traditional and modern building types in the old city shows that there are similarities between these types, which suggest that these types are part of the old fabric of the city and they define the morphology of the old city. The study concluded that the morphology of the old city is the product of property in two dimensions (ownership parcels), and the building types on them.
875

Z-source, Full Bridge Dc/dc Converter

Pekuz, Cagdas 01 December 2010 (has links) (PDF)
The thesis is related to investigate characteristics and performance of a Z-source full bridge dc/dc converter which boosts the input voltage to a higher output voltage. Zsource structure increases the reliability of the converter according to current fed full bridge dc/dc converter and also reducing the complexity according to two stage design approach (boost followed by full bridge). Operating principles of the Z-source dc-dc converter is described by current and voltage waveforms of the components and mathematical expressions. Moreover, small signal models and transfer functions are derived for both continuous current mode (CCM) and discontinuous current mode (DCM) operations of the converter. Waveforms obtained, mathematical expressions, small signal models and transfer functions derived are confirmed by simulations. Performance of the converter and controller are both tested in laboratory prototype.
876

Production Of Z + Jet And Hf Jet Energy Scale Calibration At 7 Tev In The Cms Experiment At Lhc

Bilin, Bugra 01 September 2011 (has links) (PDF)
Forward Jet Calibration for CMS detector is presented using Z boson + jet event samples in the pseudorapidity region of 0 &lt / |&eta / | &lt / 5. The results are based on proton-proton collision data at center of mass energy of &radic / s = 7 TeV corresponding to &sim / 1 fb&minus / 1 of data. Z bosons are reconstructed from opposite sign lepton pairs (&mu / +&mu / &minus / , e+e&minus / ) and the transverse momentum balance of the Z boson and the associated jet is used to derive the calibration coefficients. The coefficients are tested on jets from a WW Monte Carlo sample using the W-mass constraint. The W mass peak position is observed to be improved by 20 % without loss of resolution.
877

Search For Z

Sahin, Mehmet Ozgur 01 April 2012 (has links) (PDF)
In this thesis, analysis of the forward backward asymmetry of high energy electron pairs at the CMS - LHC with a centre of mass energy of 7 TeV is presented and the possibility of search for a new neutral weak boson Z&rsquo / via measuring the forward backward asymmetry AFB of high energy electron pairs is discussed. The forward backward asymmetry is a natural result of the interference between the neutral current mediators: Photon and Z boson. A new neutral gauge boson would also interfere with these mediators and this new interference would either enhance the forward backward asymmetry at high energies or suppress it. In this analysis, 4.67 fb&minus / 1 data collected at the CMS experiment in 2011 is used
878

Distribution Network Modeling and Capacitor Placement Application

Su, Yuh-Sheng 14 August 2002 (has links)
Enhancing the quality of services in the distribution system is an important topic for power system research. It is imperative to employ precise network modeling and effective simulation tools, and a good system model is the key. This dissertation starts with modifying the building algorithms of Y-admittance and Z-impedance matrices. The Y-matrix will be built according to phase sequences. With the facts that the line self-impedance is significantly greater than the mutual-coupling terms and the existence of a high r/x ratio in distribution, two decoupled load flow methods (Phase-Decoupled¡BPD and Sub-Phase-Decoupled¡BSPD) with Current Injection Model(CIM) were developed. A new Z-matrix building algorithm was also developed in this dissertation. It decomposed the traditional Z into two sub-matrices, the upper and lower triangular matrices respectively. The matrices represent the relationships between the branch current and the bus injection current, and between the bus voltage and the branch current. Enhancing the quality of services will be effectively achieved by a proper capacitor placement technique. This dissertation develops a linear relationships of voltage changes versus the capacitor compensation, the branch current changes versus the capacitor compensation, and loss reductions versus the capacitor compensation. For loss reduction, a linear optimization function was defined to solve the capacitor placement problem. Tests have shown that the proposed methods were suitable for applications to an unbalance distribution system.
879

Estetisk och teknisk karaktärsdesign : Hur en kvinnlig antagonist skapas med konventioner utifrån etablerade spel .

Hajjar, Elie January 2009 (has links)
<p>Examensarbetets stora fokus baseras på hur en kvinnlig antagonist skapas både utifrånestetiska och praktiska premisser. För den estetiska och tekniska normen utgick jag ifrånspelet Devil May Cry 4 (Capcom, 2008). Utifrån spelets modeller kunde en studie genomföraspå enstaka karaktärer där de tekniska begränsningar och den estetiska utformningen kundefastställas. Först har jag skapat ett koncept som baseras på de estetiska valen, och utifrånstudien fick jag fram informationen där jag kunde med hjälp av 3d program som användsinom spelbranschen tag fram en egen karaktär, i det här fallet en kvinnlig antagonist.Jag har velat skapa en kvinnlig spelkaraktär utifrån konventioner som samtidigt utmanas. Denkvinnliga antagonisten baseras på estetiska val och teman som framhäver karaktärenspersonlighet. Mina problemställningar är Hur kan koder och konventioner användas för attskapa en stark och framträdande kvinnlig karaktär? Och Hur kan de estetiska tillvalenappliceras med dagens tekniska metoder?</p>
880

A comparison of meta-analytic approaches to the analysis of reliability estimates [electronic resource] / by Denise Corinne Mason.

Mason, Denise Corinne. January 2003 (has links)
Includes vita. / Title from PDF of title page. / Document formatted into pages; contains 114 pages. / Thesis (Ph.D.)--University of South Florida, 2003. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: In the last few years, several studies have attempted to meta-analyze reliability estimates. The initial study, to outline a methodology for meta-analyzing reliability coefficients, was published by Vacha-Haase in 1998. Vacha-Haase used a very basic meta-analytic model to find a mean effect size (reliability) across studies. There are two main reasons for meta-analyzing reliability coefficients. First, recent research has shown that many studies fail to report the appropriate reliability for the measure and population of the actual study (Vacha-Haase, Ness, Nilsson and Reetz, 1999; Whittington, 1998; Yin and Fan, 2000). Second, very little research has been published describing the way reliabilities for the same measure vary according to moderators such as time, form length, population differences in trait variability and others. / ABSTRACT: Vacha-Haase (1998) proposed meta-analysis, as a method by which the impact of moderators may become better understood. Although other researchers have followed the Vacha-Haase example and meta-analyzed the reliabilities for several measures, little has been written about the best methodology to use for such analysis. Reliabilities are much larger on average than are validities, and thus tend to show greater skew in their sampling distributions. This study took a closer look at the methodology with which reliability can be meta-analyzed. Specifically, a Monte Carlo study was run so that population characteristics were known. This provided a unique ability to test how well each of three methods estimates the true population characteristics. / ABSTRACT: The three methods studied were the Vacha-Haase method as outlined in her 1998 article, the well-known Hunter and Schmidt "bare bones method" (1990) and the random-effects version of Hedges' method as described by Lipsey and Wilson (2001). The methods differ both in how they estimate the random-effects variance component (or in one case, whether the random-effects variance component is estimated at all) and in how they treat moderator variables. Results showed which of these methods is best applied to reliability meta-analysis. A combination of the Hunter and Schmidt (1999) method and weighted least squares regression is proposed. / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.

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