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Pippi Goes Abroad : A comparative study of the British and American translations of neologisms, nonce words and proper nouns in Pippi LongstockingMoats, Madelene January 2009 (has links)
The purpose of this study is to analyze two literary translations of Astrid Lindgren’s Pippi Långstrump (Lindgren, 1945) from Swedish into English. The study compares the British and the American English translations of neologisms, nonce words and proper nouns. The primary data chosen for this study are the Swedish children’s book Pippi Långstrump (1945), written by Astrid Lindgren, and its 1954 British translation, by Edna Hurup, as well as the 1977 American English translation, by Florence Lamborn. The method used in this study is qualitative, and consists of an in-depth analysis of representative examples of neologisms, nonce words and proper nouns. Three research questions aimed at finding out what translation procedures were used, whether there were any differences between the two translations, and whether there were any semantic changes in the two translations. The conclusion is that the most common translation procedure used is equivalence. The most distinguishing difference between the two translations is that the American English translation seems to stay more true to the original text, whereas the British translation has a greater respect for the target text reader, in the sense that it is more culturally adapted than the American English translation. There were no major semantic changes in the samples from the two translations, with the exception of a few examples. In conclusion, both translators manage to maintain the atmosphere of the original text.
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Reduced-Order Modeling of Multiscale Turbulent Convection: Application to Data Center Thermal ManagementRambo, Jeffrey D. 27 March 2006 (has links)
Data centers are computing infrastructure facilities used by industries with large data processing needs and the rapid increase in power density of high performance computing equipment has caused many thermal issues in these facilities. Systems-level thermal management requires modeling and analysis of complex fluid flow and heat transfer processes across several decades of length scales. Conventional computational fluid dynamics and heat transfer techniques for such systems are severely limited as a design tool because their large model sizes render parameter sensitivity studies and optimization impractically slow.
The traditional proper orthogonal decomposition (POD) methodology has been reformulated to construct physics-based models of turbulent flows and forced convection. Orthogonal complement POD subspaces were developed to parametrize inhomogeneous boundary conditions and greatly extend the use of the existing POD methodology beyond prototypical flows with fixed parameters. A flux matching procedure was devised to overcome the limitations of Galerkin projection methods for the Reynolds-averaged Navier-Stokes equations and greatly improve the computational efficiency of the approximate solutions. An implicit coupling procedure was developed to link the temperature and velocity fields and further extend the low-dimensional modeling methodology to conjugate forced convection heat transfer. The overall reduced-order modeling framework was able to reduce numerical models containing 105 degrees of freedom (DOF) down to less than 20 DOF, while still retaining greater that 90% accuracy over the domain.
Rigorous a posteriori error bounds were formulated by using the POD subspace to partition the error contributions and dual residual methods were used to show that the flux matching procedure is a computationally superior approach for low-dimensional modeling of steady turbulent convection.
To efficiently model large-scale systems, individual reduced-order models were coupled using flow network modeling as the component interconnection procedure. The development of handshaking procedures between low-dimensional component models lays the foundation to quickly analyze and optimize the modular systems encountered in electronics thermal management. This modularized approach can also serve as skeletal structure to allow the efficient integration of highly-specialized models across disciplines and significantly advance simulation-based design.
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Person Name Recognition In Turkish Financial Texts By Using Local Grammar ApproachBayraktar, Ozkan 01 September 2007 (has links) (PDF)
Named entity recognition (NER) is the task of identifying the named entities (NEs) in the texts and classifying them into semantic categories such as person, organization, and place names and time, date, monetary, and percent expressions. NER has two principal aims: identification of NEs and classification of them into semantic categories. The local grammar (LG) approach has recently been shown to be superior to other NER techniques such as the probabilistic approach, the symbolic approach, and the hybrid approach in terms of being able to work with untagged corpora. The LG approach does not require using any
dictionaries and gazetteers, which are lists of proper nouns (PNs) used in NER applications, unlike most of the other NER systems. As a consequence, it is able to recognize NEs in previously unseen texts at minimal costs. Most of the NER systems are costly due to manual rule compilation especially in large tagged corpora. They also require some semantic and syntactic analyses to be applied before pattern generation process, which can be avoided by using the LG approach.
In this thesis, we tried to acquire LGs for person names from a large untagged Turkish financial news corpus by using an approach successfully applied to a Reuter&rsquo / s financial English news corpus recently by H. N. Traboulsi. We explored its applicability to Turkish language by using frequency, collocation, and concordance analyses. In addition, we constructed a list of Turkish reporting verbs. It is an important part of this study because there is no major study about reporting verbs in Turkish.
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<em>Pippi</em> Goes Abroad : A comparative study of the British and American translations of neologisms, nonce words and proper nouns in <em>Pippi Longstocking</em>Moats, Madelene January 2009 (has links)
<p>The purpose of this study is to analyze two literary translations of Astrid Lindgren’s <em>Pippi Långstrump </em>(Lindgren, 1945)<em> </em>from Swedish into English. The study compares the British and the American English translations of neologisms, nonce words and proper nouns. The primary data chosen for this study are the Swedish children’s book <em>Pippi Långstrump </em>(1945), written by Astrid Lindgren, and its 1954 British translation, by Edna Hurup, as well as the 1977 American English translation, by Florence Lamborn. The method used in this study is qualitative, and consists of an in-depth analysis of representative examples of neologisms, nonce words and proper nouns. Three research questions aimed at finding out what translation procedures were used, whether there were any differences between the two translations, and whether there were any semantic changes in the two translations. The conclusion is that the most common translation procedure used is equivalence. The most distinguishing difference between the two translations is that the American English translation seems to stay more true to the original text, whereas the British translation has a greater respect for the target text reader, in the sense that it is more culturally adapted than the American English translation. There were no major semantic changes in the samples from the two translations, with the exception of a few examples. In conclusion, both translators manage to maintain the atmosphere of the original text.<strong></strong></p><p><strong> </strong></p>
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Spatio-temporal correlations of jets using high-speed particle image velocimetryPokora, C. D. January 2009 (has links)
The major source of aircraft noise at take-off is jet noise. If jet noise is not adequately addressed environmental impact concerns will constrain the planned growth of the air transport system. A considerable amount of research worldwide has therefore been aimed at identifying ways to reduce jet noise including development of a predictive tool that can estimate the noise generated by new nozzle designs. Current noise prediction techniques, however, still require the input of empirically calibrated noise source models and their performance is still inadequate. In addition, development of detailed noise source identification measurements and the associated understanding of how to control (and reduce) the noise at the source has been limited. The fundamental turbulence property which acts as the source of propagating noise in shear layers is the two-point space-time velocity correlation (Rijkl). Very few measurements exist for this property to guide model development. It is therefore the aim of the work reported in this thesis to provide new experimental data that helps identify the turbulence sources located within the shear layer of jets. The technique of Partical Imaging Velocimetry (PIV) is used to capture directly the flowfield and all relevant turbulent statistics.
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Spatial Scaling of Large-Scale Circulations and Heat Transport in Turbulent Mixed ConvectionWesthoff, Andreas 14 November 2012 (has links)
No description available.
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Experimental Study of Three-Dimensional Turbulent Offset Jets and Wall JetsAgelin-Chaab, Martin 19 October 2010 (has links)
An experimental study was designed to examine and document the development
and structures of turbulent 3D offset jets. The generic 3D wall jets at the same Reynolds numbers was used as the basis of comparison. The experiments were performed using a high resolution particle image velocimetry technique to perform velocity measurements at three Reynolds numbers based on the jet exit diameter and velocities of 5000, 10000
and 20000 and four jet offset height ratios of 0.5, 1.0, 2.0 and 4.0. The measurements were performed in the streamwise/wall-normal plane from 0 to 120 jet exit diameters and in the streamwise/lateral plane from 10 to 80 jet exit diameters. The velocity data were analyzed using (i) mean velocities and one-point statistics such as turbulence intensities,
Reynolds stresses, triple velocity products and some terms in the transport equations for the turbulence kinetic energy, (ii) two-point velocity correlations to study how the turbulence quantities are correlated as well as the length scale and angle of inclination of
the hairpin-like vortex structures, and (iii) proper orthogonal decomposition to examine the energy distribution and the role of the large scale structures in the turbulence intensities and Reynolds shear stresses.
The decay of the maximum mean velocities and spread of the jet half widths
became independent of Reynolds number much earlier in the generic wall jet than the offset jets. The flow development is delayed with increasing offset heights.
The decay rate and wall-normal spread rate increased with the offset heights, whereas the lateral spread rate decreased with offset heights, which is consistent with previous studies.
The two-point auto-correlations and the proper orthogonal decomposition results indicate the presence of more large scale structures in the outer and self-similar regions than in the inner and developing regions. The iso-contours of the streamwise autocorrelations in the inner regions were inclined at similar angles of β = 11.2 ± 0.6 degrees, which are in good agreement with reported values in boundary layer studies. The angles decrease with increasing distance from the wall.
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Model Reduction for Vehicle Systems ModellingNguyen, Khanh V. Q. 30 April 2014 (has links)
The full model of a double-wishbone suspension has more than 30 differential-algebraic equations which takes a remarkably long time to simulate. By contrast, the look-up table for the same suspension is simulated much faster, but may not be very accurate. Therefore, developing reduced models that approximate complex systems is necessary because model reduction decreases the simulation time in comparison with the original model, enables real time applications, and produces acceptable accuracy.
In this research, we focus on model reduction techniques for vehicle systems such as suspensions and how they are approximated by models having lower degrees of freedom. First, some existing model reduction techniques, such as irreducible realization procedures, balanced truncation, and activity-based reduction, are implemented to some vehicle suspensions. Based on the application of these techniques, their disadvantages are revealed. Then, two methods of model reduction for multi-body systems are proposed.
The first proposed method is 2-norm power-based model reduction (2NPR) that combines 2-norm of power and genetic algorithms to derive reduced models having lower degrees of freedom and fewer number of components. In the 2NPR, some components such as mass, damper, and spring are removed from the original system. Afterward, the values of the remaining components are adjusted by the genetic algorithms. The most important advantage of the 2NPR is keeping the topology of multi-body systems which is useful for design purposes.
The second method uses proper orthogonal decomposition. First, the equations of motion for a multi-body system are converted to explicit second-order differential equations. Second, the projection matrix is obtained from simulation or experimental data by proper orthogonal decomposition. Finally, the equations of motion are transferred to a lower-dimensional state coordinate system.
The implementation of the 2NPR to two double-wishbone suspensions and the comparison with other techniques such as balanced truncation and activity-based model reduction also demonstrate the efficiency of the new reduction technique.
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Experimental Study of Roughness Effect on Turbulent Shear Flow Downstream of a Backward Facing StepEssel, Ebenezer Ekow 16 January 2014 (has links)
An experimental study was undertaken to investigate the effect of roughness on the characteristics of separated and reattached turbulent shear flow downstream of a backward facing step. Particle image velocimetry technique was used to conducted refined velocity measurements over a reference smooth acrylic wall and rough walls produced from sandpaper 36 and 24 grits positioned downstream of a backward facing step, one after another. Each experiment was conducted at Reynolds number based on the step height and centerline mean velocity of 7050. The results showed that sandpaper 36 and 24 grits increased the reattachment length by 5% and 7%, respectively, compared with the value obtained over the smooth wall. The distributions of the mean velocities, Reynolds stresses, triple velocity correlations and turbulence production are used to examine roughness effects on the flow field downstream of the backward facing step. Two-point auto-correlation function and proper orthogonal decomposition (POD) are also used to investigate the impact of wall roughness on the large scale structures.
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Vortices in turbulent curved pipe flow-rocking, rolling and pulsating motionsKalpakli Vester, Athanasia January 2014 (has links)
This thesis is motivated by the necessity to understand the flow structure of turbulent flows in bends encountered in many technical applications such as heat exchangers, nuclear reactors and internal combustion engines. Flows in bends are characterised by strong secondary motions in terms of counter-rotating vortices (Dean cells) set up by a centrifugal instability. Specifically the thesis deals with turbulent flows in 90° curved pipes of circular cross-section with and without an additional motion, swirling or pulsatile, superposed on the primary flow. The aim of the present thesis is to study these complex flows in detail by using time-resolved stereoscopic particle image velocimetry to obtain the three-dimensional velocity field, with complementary hot-wire anemometry and laser Doppler velocimetry measurements. In order to analyse the vortical flow field proper orthogonal decomposition (POD) is used. The so called ``swirl-switching'' is identified and it is shown that the vortices instantaneously, ``rock'' between three states, viz. a pair of symmetric vortices or a dominant clockwise or counter-clockwise Dean cell. The most energetic mode exhibits a single cell spanning the whole cross-section and ``rolling'' (counter-)clockwise in time. However, when a honeycomb is mounted at the inlet of the bend, the Dean vortices break down and there is strong indication that the ``swirl-switching'' is hindered. When a swirling motion is superimposed on the incoming flow, the Dean vortices show a tendency to merge into a single cell with increasing swirl intensity. POD analysis show vortices which closely resemble the Dean cells, indicating that these structures co-exist with the swirling motion. In highly pulsating turbulent flow at the exit of a curved pipe, the vortical pattern is diminished or even eliminated during the acceleration phase and then re-established during the deceleration. In order to investigate the effect of pulsations and curvature on the performance of a turbocharger turbine, highly pulsating turbulent flow through a sharp bend is fed into the turbine. Time-resolved pressure and mass-flow rate measurements show that the hysteresis loop in the pressure-ratio-mass-flow plane, may differ significantly between straight and curved inlets, however the mean operating point is only slightly affected. / <p>QC 20140523</p>
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