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1
Rashid, Adnan. "Investigation of through-thickness assembly stresses in composite wing spars". Thesis, University of Bristol, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.722699.
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Mehler, Felix Eckhart. "The structural testing and modification of a full-scale ornithopter's wing spars". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq29368.pdf.
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Blondeau, Julie E. "Development and testing of a variable aspect ratio wing using pneumatic telescopic spars". College Park, Md. : University of Maryland, 2004. http://hdl.handle.net/1903/1761.
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Thesis (M.S.) -- University of Maryland, College Park, 2004.Thesis research directed by: Dept. of Aerospace Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
4
De, Shuvodeep. "Structural Modeling and Optimization of Aircraft Wings having Curvilinear Spars and Ribs (SpaRibs)". Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/88467.
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The aviation industry is growing at a steady rate but presently, the industry is highly dependent on fossil fuel. As the world is running out of fossil fuels and the wide-spread acceptance of climate change due to carbon emissions, both the governments and industry are spending a significant amount of resources on research to reduce the weight and hence the fuel consumption of commercial aircraft. A commercial fixed-wing aircraft wing consists of spars which are beams running in span-wise direction, carrying the flight loads and ribs which are panels with holes attached to the spars to preserve the outer airfoil shape of the wing. Kapania et al. at Virginia Tech proposed the concept of reducing the weight of aircraft wing using unconventional design of the internal structure consisting of curvilinear spars and ribs (known as SpaRibs) for enhanced performance. A research code, EBF3GLWingOpt, was developed by the Kapania Group. at Virginia Tech to find the best configuration of SpaRibs in terms of weight saving for given flight conditions. However, this software had a number of limitations and it can only create and analyze limited number of SpaRibs configurations. In this work, the limitations of the EBF3GLWingOpt code has been identified and new algorithms have been developed to make is robust and analyze larger number of SpaRibs configurations. The code also has the capability to create cut-outs in the SpaRibs for passage of fuel pipes and wirings. This new version of the code can be used to find best SpaRibs configuration for multiple objectives such as reduction of weight and increase flutter velocity. The code is developed in Python language and it has parallel computational capabilities. The wing is modeled using commercial FEA software, MSC.PATRAN and analyzed using MSC.NASTRAN which are from within EBF3GLWingOpt. Using this code a significant weight reduction for a transport aircraft wing has been achieved.PHD
5
Carlowitz, Christian, Thomas Girg, Hatem Ghaleb i Xuan-Quang Du. "Efficient Ultra-High Speed Communication with Simultaneous Phase and Amplitude Regenerative Sampling (SPARS)". De Gruyter, 2017. https://tud.qucosa.de/id/qucosa%3A38596.
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For ultra-high speed communication systems at high center frequencies above 100 GHz, we propose a disruptive change in system architecture to address major issues regarding amplifier chains with a large number of amplifier stages. They cause a high noise figure and high power consumption when operating close to the frequency limits of the underlying semiconductor technologies. Instead of scaling a classic homodyne transceiver system, we employ repeated amplification in single-stage amplifiers through positive feedback as well as synthesizer-free self-mixing demodulation at the receiver to simplify the system architecture notably. Since the amplitude and phase information for the emerging oscillation is defined by the input signal and the oscillator is only turned on for a very short time, it can be left unstabilized and thus come without a PLL. As soon as gain is no longer the most prominent issue, relaxed requirements for all the other major components allow reconsidering their implementation concepts to achieve further improvements compared to classic systems. This paper provides the first comprehensive overview of all major design aspects that need to be addressed upon realizing a SPARS-based transceiver. At system level, we show how to achieve high data rates and a noise performance comparable to classic systems, backed by scaled demonstrator experiments. Regarding the transmitter, design considerations for efficient quadrature modulation are discussed. For the frontend components that replace PA and LNA amplifier chains, implementation techniques for regenerative sampling circuits based on super-regenerative oscillators are presented. Finally, an analog-to-digital converter with outstanding performance and complete interfaces both to the analog baseband as well as to the digital side completes the set of building blocks for efficient ultra-high speed communication.
6
Wynn, Milton E. "Spare parts nonavailability : the identification of impediments to spares acquisition". Thesis, Monterey, California. Naval Postgraduate School, 1992. http://hdl.handle.net/10945/24042.
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Sohaib, Muhammad. "Parameterized Automated Generic Model for Aircraft Wing Structural Design and Mesh Generation for Finite Element Analysis". Thesis, Linköpings universitet, Maskinkonstruktion, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-71264.
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This master thesis work presents the development of a parameterized automated generic model for the structural design of an aircraft wing. Furthermore, in order to perform finite element analysis on the aircraft wing geometry, the process of finite element mesh generation is automated. Aircraft conceptual design is inherently a multi-disciplinary design process which involves a large number of disciplines and expertise. In this thesis work, it is investigated how high-end CAD software‟s can be used in the early stages of an aircraft design process, especially for the design of an aircraft wing and its structural entities wing spars and wing ribs. The generic model that is developed in this regard is able to automate the process of creation and modification of the aircraft wing geometry based on a series of parameters which define the geometrical characteristics of wing panels, wing spars and wing ribs.Two different approaches are used for the creation of the generic model of an aircraft wing which are “Knowledge Pattern” and “PowerCopy with Visual Basic Scripting” using the CATIA V5 software. A performance comparison of the generic wing model based on these two approaches is also performed. In the early stages of the aircraft design process, an estimate of the structural characteristic of the aircraft wing is desirable for which a surface structural analysis (using 2D mesh elements) is more suitable. In this regard, the process of finite element mesh generation for the generic wing model is automated. The finite element mesh is generated for the wing panels, wing spars and wing ribs. Furthermore, the finite element mesh is updated based on any changes in geometry and the shape of the wing panels, wing spars or wing ribs, and ensure that all the mesh elements are always properly connected at the nodes. The automated FE mesh generated can be used for performing the structural analysis on an aircraft wing.
8
Cox-Richard, Lillian. "Spark Gap". VCU Scholars Compass, 2008. http://scholarscompass.vcu.edu/etd/698.
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"Spark Gap" is an invisible electrical force made visible in spaces between things. This usually describes the space of air between two conductors; a non-conductive gap in an otherwise complete electric circuit, across which a quick luminous disruptive electrical discharge occurs. This interstitial space is the distance between two ideas, arced with a running leap. The arc can also be the difference between two things, a gap that becomes apparent only when the two are held in close proximity. In my thesis exhibition, "Spark Gap," a sea urchin shaped orb sits atop a tower of ladders. The orb is broken into five sections and reassembled, each fault line occurring along the perfect zigzag line of its cellular structure. On the floor, there is a linen shag rug, marked as if struck by lightning. This exhibition is named for an interstitial charge, arcing across distance or difference. But this charge is also found in intersections and similarities. Imagine the friction created by rubbing together the circles of a Venn diagram: the overlapping section would begin to spark. It is in these gaps and overlaps that I find the impetus for my work.
9
Lustig, Michael. "Sparse MRI /". May be available electronically:, 2008. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
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Lowas, Albert Frank III. "Improved Spare Part Forecasting for Low Quantity Parts with Low and Increasing Failure Rates". Wright State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=wright1432380369.
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Ramachandran, Shridhar. "Incremental PageRank acceleration using Sparse Matrix-Sparse Vector Multiplication". The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1462894358.
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Sphar, Shannah R. "Participant training and its effect on actual retrospective timeframes". View electronic thesis, 2008. http://dl.uncw.edu/etd/2008-2/sphars/shannahsphar.pdf.
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Summers, Andrew John. "SPAARS evidence? : an empirical investigation into SPAARS applied to PTSD". Thesis, University of Edinburgh, 2003. http://hdl.handle.net/1842/27487.
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Empirical evidence for the SPAARS (Schematic, Prepositional, Associative and Analogical Representational Systems) model (Power & Dalgleish, 1997, 1999; Power, 1997, 1999), as applied to post-traumatic stress disorder (PTSD) by Dalgleish (1999, submitted) was investigated. An opportunistic sample of 12 participants was recruited from a specialist service for PTSD. Participants had experienced a variety of traumatic events. Co-morbidity and PTSD severity were representative of the service's normal clinical population. Participants were assessed up to 3 times. An interview to assess schematic themes was devised for this study and standardised measures of PTSD and other symptomatology were also administered. The interview was found to have reasonable inter-rater reliability. The combined results of the analyses provided initial support for the utility of the SPAARS model applied to PTSD. Particular Schematic-level representations were identified, which were associated with PTSD and other symptomatology. Participants were found to experience a wide range of aversive emotions and fear was not generally the dominant emotion reported. Greater negative emotionality, rather than greater fear, was associated with increased symptomatology. Some theoretical and clinical implications of these findings are discussed.
14
Monastyrsky, G. E., P. Ochin, A. V. Gilchuk i V. I. Kolomytsev. "Spark plasma sintering the spark-erosion powders of functional alloys". Thesis, Sumy State University, 2011. http://essuir.sumdu.edu.ua/handle/123456789/20798.
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Various shape memory alloys (Ti-Ni-Hf, Ni-Al and Cu-Al-Ni) were elaborated by
spark plasma sintering method from the micron, submicron and nano- sized particles
prepared by spark-erosion method in cryogenic liquid from preliminary melted master
alloys. These alloys are being developed as one of the alternatives for the intermediate
temperature applications (100-900oC). Spark plasma sintering method is express
method, which provides lower temperature and shorter holding time of sintering. It
makes possible to sinter materials from the pre-alloyed powders and eliminate the
intensive grains growth and precipitating processes influencing the mechanical and
functional properties of functional materials. The effects of processing parameters on the
martensitic transformation and microstructure of the sintered compacts were
investigated using XRD and SEM study. Temperatures of sintering were chosen
according to the assessed data of the decomposition, oxidation and others processes
carrying out in material. Although the precipitating processes were usually not
completely depressed, the intensive grain growth was also not found in most cases. Most
of the microstructure peculiarities of as processed powder were inherited by the sintered
material.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/20798
15
Boeckx, W. D. "Recycling spare parts". Maastricht : Maastricht : Maastricht University ; University Library, Maastricht University [Host], 1999. http://arno.unimaas.nl/show.cgi?fid=13042.
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Kalk, Jonathan W. "Sparse ordinary graphs". Thesis, University of Hawaii at Manoa, 2005. http://hdl.handle.net/10125/25937.
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Ordinary graphs are directed graphs that can be viewed as generalizations of symmetric block designs. They were introduced by Fossorier, Jezek, Nation and Pogel in [2] in an attempt to construct new finite projective planes. In this thesis we investigate some special cases of ordinary graphs, most prominently the case where nonadjacent vertices have no common neighbors. We determine all connected graphs of this type that exist.vii, 65 leaves, bound ; 29 cm.
Thesis (Ph. D.)--University of Hawaii at Manoa, 2005.
17
Samandari, Farshid. "Sparks of Union". Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/46483.
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This document delves into the precept of unity in diversity from a musical perspective, in order to replace the timeworn aesthetic norms with ones that may induce a music befitting the fabric of our contemporary global village. It deals with the contemporary musical zeitgeist from this perspective and examines the transformations in musical substance derived from the copious changes in dissemination since the information revolution. It also presents Sparks of Union, a 20-minute composition for ten Western instruments and interactive electronics. This composition aims to focus on different musical languages in search of polarizing and uniting elements, and explores free interactions between the different musical elements. As a result it strives to create new sonorities derived from a fully democratic multicultural interaction.
18
Willcocks, Christopher George. "Sparse volumetric deformation". Thesis, Durham University, 2013. http://etheses.dur.ac.uk/8471/.
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Volume rendering is becoming increasingly popular as applications require realistic solid shape representations with seamless texture mapping and accurate filtering. However rendering sparse volumetric data is difficult because of the limited memory and processing capabilities of current hardware. To address these limitations, the volumetric information can be stored at progressive resolutions in the hierarchical branches of a tree structure, and sampled according to the region of interest. This means that only a partial region of the full dataset is processed, and therefore massive volumetric scenes can be rendered efficiently. The problem with this approach is that it currently only supports static scenes. This is because it is difficult to accurately deform massive amounts of volume elements and reconstruct the scene hierarchy in real-time. Another problem is that deformation operations distort the shape where more than one volume element tries to occupy the same location, and similarly gaps occur where deformation stretches the elements further than one discrete location. It is also challenging to efficiently support sophisticated deformations at hierarchical resolutions, such as character skinning or physically based animation. These types of deformation are expensive and require a control structure (for example a cage or skeleton) that maps to a set of features to accelerate the deformation process. The problems with this technique are that the varying volume hierarchy reflects different feature sizes, and manipulating the features at the original resolution is too expensive; therefore the control structure must also hierarchically capture features according to the varying volumetric resolution. This thesis investigates the area of deforming and rendering massive amounts of dynamic volumetric content. The proposed approach efficiently deforms hierarchical volume elements without introducing artifacts and supports both ray casting and rasterization renderers. This enables light transport to be modeled both accurately and efficiently with applications in the fields of real-time rendering and computer animation. Sophisticated volumetric deformation, including character animation, is also supported in real-time. This is achieved by automatically generating a control skeleton which is mapped to the varying feature resolution of the volume hierarchy. The output deformations are demonstrated in massive dynamic volumetric scenes.
19
Kim, Kwanghoon. "Infrared luminescence from spark-processed silicon and erbium-doped spark-processed silicon". [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0012860.
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Schafmeister, Frank. "Indirekte Sparse-Matrix Konverter /". Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17428.
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Walls, Kate. "Muriel Spark and Catholicism". Thesis, Queen's University Belfast, 2014. https://pure.qub.ac.uk/portal/en/theses/muriel-spark-and-catholicism(2d16b200-588b-4866-a1d6-dea6396b68cb).html.
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My PhD thesis analyses Catholic themes in the novel,s of Scottish born writer Muriel Spark. Spark's career spanned five decades, and much of her work was influenced by her conversion to Catholicism. She is a sophisticated and enigmatic writer whose work defies categorisation. Part of this difficulty stems from her position as "other" within Catholicism· -a result of her conversion and her refusal to adhere to traditional Catholic gender roles. What does become clear upon examining Spark's fiction is that she uses subversive and paradoxical rhetoric to highlight the problems inherent in being unable to fully comprehend God's mystery. Spark appears to be obsessed with several religious concepts that appear constantly in her fiction. In the case of the Catholic convert and the Book of Job, these threads appear repeatedly and build to a climax-once Spark comprehensively addresses them in her fiction, the threads disappears from her work entirely. In exploring these Catholic themes, it becomes clear that, despite Spark's work being abundant with references to religion, there is very little narrative space devoted to the character's internal thoughts regarding God and religious thought. I argue that in Spark's fiction, creativity is a proxy for religious faith. Spark draws parallels to the personal and individual nature of both, but devotes more narrative space to explaining a sense of faith in the creative process. She also appears to grant narrative endorsement to characters who believe in and ate guided by their creativity, even when they clearly traverse the boundaries of acceptable "moral" behaviour.
22
Denil, Misha. "Recklessly approximate sparse coding". Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/43662.
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Introduction of the so called “K-means” or “triangle” features in Coates,
Lee and Ng, 2011 caused significant discussion in the deep learning
community. These simple features are able to achieve state of the art performance on standard image classification benchmarks, outperforming much
more sophisticated methods including deep belief networks, convolutional
nets, factored RBMs, mcRBMs, convolutional RBMs, sparse autoencoders
and several others. Moreover, these features are extremely simple and easy
to compute.
Several intuitive arguments have been put forward to describe this remarkable performance, yet no mathematical justification has been offered.
In Coates and Ng, 2011, the authors improve on the triangle features
with “soft threshold” features, adding a hyperparameter to tune performance, and compare these features to sparse coding. Both soft thresholding and sparse coding are found to often yield similar classification results,
though soft threshold features are much faster to compute.
The main result of this thesis is to show that the soft threshold features
are realized as a single step of proximal gradient descent on a non-negative
sparse coding objective. This result is important because it provides an
explanation for the success of the soft threshold features and shows that
even very approximate solutions to the sparse coding problem are sufficient
to build effective classifiers.
23
Mahajan, Rohan. "Adaptive scheduling in Spark". Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/105977.
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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (page 33).
Because most data processing systems are distributed in nature, data must be transferred between machines. Currently, Spark, a prominent such system, predetermines the strategies for shuffling this data, but in certain situations, different shuffle strategies would improve performance. We add functionality to track metrics about the data during the job and appropriately adapt the shuffle strategy. We show improvements in ShuffledRDD performance, joins using Spark's RDD interface, and joins in Spark SQL.
by Rohan Mahajan.
M. Eng.
24
Chen, George H. "Deformation-invariant sparse coding". Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/75709.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 87-91).
Sparse coding represents input signals each as a sparse linear combination of a set of basis or dictionary elements where sparsity encourages representing each input signal with a few of the most indicative dictionary elements. In this thesis, we extend sparse coding to allow dictionary elements to undergo deformations, resulting in a general probabilistic model and accompanying inference algorithm for estimating sparse linear combination weights, dictionary elements, and deformations. We apply our proposed method on functional magnetic resonance imaging (fMRI) data, where the locations of functional regions in the brain evoked by a specific cognitive task may vary across individuals relative to anatomy. For a language fMRI study, our method identifies activation regions that agree with known literature on language processing. Furthermore, the deformations learned by our inference algorithm produce more robust group-level effects than anatomical alignment alone.
by George H. Chen.
S.M.
25
Will, Sebastian, i Hosna Jabbari. "Sparse RNA folding revisited". Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-204163.
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Background: RNA secondary structure prediction by energy minimization is the central computational tool for the analysis of structural non-coding RNAs and their interactions. Sparsification has been successfully applied to improve the time efficiency of various structure prediction algorithms while guaranteeing the same result; however, for many such folding problems, space efficiency is of even greater concern, particularly for long RNA sequences. So far, spaceefficient sparsified RNA folding with fold reconstruction was solved only for simple base-pair-based pseudo-energy models. Results: Here, we revisit the problem of space-efficient free energy minimization. Whereas the space-efficient minimization of the free energy has been sketched before, the reconstruction of the optimum structure has not even been discussed. We show that this reconstruction is not possible in trivial extension of the method for simple energy models. Then, we present the time- and space-efficient sparsified free energy minimization algorithm SparseMFEFold that guarantees MFE structure prediction. In particular, this novel algorithm provides efficient fold reconstruction based on dynamically garbage-collected trace arrows. The complexity of our algorithm depends on two parameters, the number of candidates Z and the number of trace arrows T; both are bounded by n2, but are typically much smaller. The time complexity of RNA folding is reduced from O(n3) to O(n2 + nZ); the space complexity, from O(n2) to O(n + T + Z). Our empirical results show more than 80 % space savings over RNAfold [Vienna RNA package] on the long RNAs from the RNA STRAND database (≥2500 bases). Conclusions: The presented technique is intentionally generalizable to complex prediction algorithms; due to their high space demands, algorithms like pseudoknot prediction and RNA–RNA-interaction prediction are expected to profit even stronger than \"standard\" MFE folding. SparseMFEFold is free software, available at http://www.bioinf.unileipzig. de/~will/Software/SparseMFEFold.
26
Choy, Tze Leung. "Sparse distance metric learning". Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:a98695a3-0a60-448f-9ec0-63da3c37f7fa.
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A good distance metric can improve the accuracy of a nearest neighbour classifier. Xing et al. (2002) proposed distance metric learning to find a linear transformation of the data so that observations of different classes are better separated. For high-dimensional problems where many un-informative variables are present, it is attractive to select a sparse distance metric, both to increase predictive accuracy but also to aid interpretation of the result. In this thesis, we investigate three different types of sparsity assumption for distance metric learning and show that sparse recovery is possible under each type of sparsity assumption with an appropriate choice of L1-type penalty. We show that a lasso penalty promotes learning a transformation matrix having lots of zero entries, a group lasso penalty recovers a transformation matrix having zero rows/columns and a trace norm penalty allows us to learn a low rank transformation matrix. The regularization allows us to consider a large number of covariates and we apply the technique to an expanded set of basis called rule ensemble to allow for a more flexible fit. Finally, we illustrate an application of the metric learning problem via a document retrieval example and discuss how similarity-based information can be applied to learn a classifier.
27
Dhanjal, Charanpal. "Sparse Kernel feature extraction". Thesis, University of Southampton, 2008. https://eprints.soton.ac.uk/64875/.
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The presence of irrelevant features in training data is a significant obstacle for many machine learning tasks, since it can decrease accuracy, make it harder to understand the learned model and increase computational and memory requirements. One approach to this problem is to extract appropriate features. General approaches such as Principal Components Analysis (PCA) are successful for a variety of applications, however they can be improved upon by targeting feature extraction towards more specific problems. More recent work has been more focused and considers sparser formulations which potentially have improved generalisation. However, sparsity is not always efficiently implemented and frequently requires complex optimisation routines. Furthermore, one often does not have a direct control on the sparsity of the solution. In this thesis, we address some of these problems, first by proposing a general framework for feature extraction which possesses a number of useful properties. The framework is based on Partial Least Squares (PLS), and one can choose a user defined criterion to compute projection directions. It draws together a number of existing results and provides additional insights into several popular feature extraction methods. More specific feature extraction is considered for three objectives: matrix approximation, supervised feature extraction and learning the semantics of two-viewed data. Computational and memory efficiency is prioritised, as well as sparsity in a direct manner and simple implementations. For the matrix approximation case, an analysis of different orthogonalisation methods is presented in terms of the optimal choice of projection direction. The analysis results in a new derivation for Kernel Feature Analysis (KFA) and the formation of two novel matrix approximation methods based on PLS. In the supervised case, we apply the general feature extraction framework to derive two new methods based on maximising covariance and alignment respectively. Finally, we outline a novel sparse variant of Kernel Canonical Correlation Analysis (KCCA) which approximates a cardinality constrained optimisation. This method, as well as a variant which performs feature selection in one view, is applied to an enzyme function prediction case study.
28
Bixler, Reid Morris. "Sparse Matrix Belief Propagation". Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/83228.
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We propose sparse-matrix belief propagation, which executes loopy belief propagation in Markov random fields by replacing indexing over graph neighborhoods with sparse-matrix operations. This abstraction allows for seamless integration with optimized sparse linear algebra libraries, including those that perform matrix and tensor operations on modern hardware such as graphical processing units (GPUs). The sparse-matrix abstraction allows the implementation of belief propagation in a high-level language (e.g., Python) that is also able to leverage the power of GPU parallelization. We demonstrate sparse-matrix belief propagation by implementing it in a modern deep learning framework (PyTorch), measuring the resulting massive improvement in running time, and facilitating future integration into deep learning models.Master of Science
29
Kjølstad, Fredrik Berg. "Sparse tensor algebra compilation". Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/128314.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2020Cataloged from PDF of thesis.
Includes bibliographical references (pages 118-128).
This dissertation shows how to compile any sparse tensor algebra expression to CPU and GPU code that matches the performance of hand-optimized implementations. A tensor algebra expression is sparse if at least one of its tensor operands is sparse, and a tensor is sparse if most of its values are zero. If a tensor is sparse, then we can store its nonzero values in a compressed data structure, and omit the zeros. Indeed, as the matrices and tensors in many important applications are extremely sparse, compressed data structures provide the only practical means to store them. A sparse tensor algebra expression may contain any number of operations, which must be compiled to fused loops that compute the entire expression simultaneously. It is not viable to support only binary expressions, because their composition may result in worse asymptotic complexity than the fused implementation.
I present compiler techniques to generate fused loops that coiterate over any number of tensors stored in different types of data structures. By design, these loops avoid computing values known to be zero due to the algebraic properties of their operators. Sparse tensor algebra compilation is made possible by a sparse iteration theory that formulates sparse iteration spaces as set expressions of the coordinates of nonzero values. By ordering iteration space dimensions hierarchically, the compiler recursively generates loops that coiterate over tensor data structures one dimension at a time. By organizing per-dimension coiteration into regions based on algebraic operator properties, it removes operations that will result in zero. And by transforming the sparse iteration spaces, it optimizes the generated code. The result is the first sparse iteration compiler, called the Tensor Algebra Compiler (taco).
Taco can compile any tensor algebra expressions, with tensors stored in different types of sparse and dense data structures, to code that matches the performance of hand-optimized implementations on CPUs and GPUs.
by Fredrik Berg Kjølstad.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science
30
Tan, Xing. "Bayesian sparse signal recovery". [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0041176.
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Blom, Jonas. "Optimizing spare-parts management". Thesis, Högskolan i Gävle, Industriell ekonomi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-28822.
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Abstract Purpose: The purpose of the study is to develop a model that will facilitate the choice of maintenance strategy within the Swedish pulp and paper industry. Without compromising system availability, the model aims to reduce inventory holding costs. Methodology: At first, a literary research was conducted to create a holistic view over the chosen topic, in time it developed into a literature framework. Secondly, a case study was conducted in order to obtain empirical data. The data were obtained through interviews and archival records. The literature framework and the empirical data were then cross-analyzed with each other. Findings: In this thesis, a model has been developed based on previously applied and accepted methods. The methods have been identified and described in order to provide a strategy in which the inventory levels- and value could be lowered. The findings indicate that the organization must seek to assign ABC-classified and VED-analyzed components different maintenance actions in order to reduce the total cost. Theoretical contribution: This thesis contributes to a methodology development regarding spare parts management. It aims to add knowledge to the existing gap regarding spare parts order point and batch size. The thesis provides a procedure in which systems including critical and expensive components are evaluated in order to assign them the appropriate maintenance. Practical relevance: The model has only been exemplified by using a system position from Stora Enso Skutskär, the numerical values are examples. The model must be tested with real values and the risk analysis must be carried out with a group of employees with great insight regarding the selected component and system position. Limitations: This thesis is delimited to spare parts management and inventory management. The study only involves one Swedish organization, whereas the organization and its spare parts management illustrates the complexity concerning spares. The model will not be verified as the focus is to highlight the research gap and to develop the model.
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Häusner, Eva-Maria. "Att spara eller inte spara? : En kvantitativ enkätstudie av informationslagringssystem för vetenskapliga artiklar". Thesis, Uppsala universitet, Institutionen för ABM, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-174967.
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Abstract Purpose This thesis aims to focus on how master students administer scholarly articles after they have found them. The purpose of the study is to detect how and to what extent people administer their articles from a personal information management-perspective (PIM). Method To answer the research questions, a web-based questionnaire survey was distributed which was announced to around 2,000 master students from different universities in Sweden. Most of the items in the survey focused on individual storage methods. The respondents were asked to rate the frequency of their different information administration behaviors on a seven level Likert-type-scale. Subsequently, items concerning specific information administration behaviors were posed, followed by questions on the respondent's sociodemographic status. The results were based on overall 316 answers. Analysis The quantitative data was analyzed using non-parametric tests such as Friedmans-test, Kruskal-Wallis-analysis, Wilcoxon-Signed Rank-test, Mann-Whitney-U-test and Chi-square-test with the statistical computer program SPSS. Findings The findings generally confirm that the majority of the surveyed graduate students are using scholarly articles. Regarding their information management, it is as usual to store the whole article as it is to store the reference. Further it is more common to choose electronic storage methods for articles and references than to use physical methods. The results highlight that most of the students use several method types and use them to varying extent. Neither age, computer skills, duration of study or satisfaction with their way of information storage influenced the quantity of used methods. Regarding specific handling, the storing of article copies on the computer’s hard drive were most frequently used. The respondents preferred furthermore to read the articles on a screen rather than printed paper versions. The influencing factors of gender, age, computer skills, subject discipline were affecting the choice of methods. General conclusions about these influencing factors are, however, complicated by possible occurring confounders. Moreover, the method types were used to different extents depending of subject discipline. Originality/value Most previous PIM research is concentrating on how people store information in general. The dealing and administrating with specific types of information are, however, rarely discussed. In the context of scholarly articles did research predominantly focus on seeking structures and reading patterns. The step between finding and reading an article has so far not directly been addressed in academic research. The study therefore is unique in addressing information storage systems of scholarly articles on such a large scale. Knowledge about storage patterns will help journal publishers and librarians to design more targeted solutions for journal systems and improve services like courses in information seeking. Paper type Two years master’s thesis
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Lau, Pik-yuk Cecilia, i 劉碧玉. "SPARC and SPARC-like 1 are associated with tumor angiogenesis in hepatocellular carcinoma". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B30284648.
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Kim, Jaecheol. "The role of radicals supplied directly and indirectly on ignition". Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53001.
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The ignition process is a critical consideration for combustion devices. External energy transfer to the combustor is required for ignition in common combustion systems. There are many ways to deposit energy into the flow but a standard method is a spark discharge because it is simple, compact, and reliable. Sparks can be categorized as either inductive or capacitive sparks that use a coil or an electrical resonance circuit with capacitor, respectively, to amplify the voltage. The creation of a successful ignition event depends on the spark energy deposited into the flow, the initial composition, pressure, temperature, turbulence level of flow etc. The deposited energy by the spark into the flow is critical for estimation of initial energy available for ignition of the mixture. Therefore, the electrical characteristics of the sparks were investigated under various flow conditions. Then measurements of deposited energy into the flow were conducted using a very accurate experimental procedure that was developed in this research. The results showed considerable electric energy losses to the electrodes for the relatively long, inductive sparks. However, the short, capacitive spark deposits electric energy into the flow with minimal loss (above 90% deposition efficiency). In addition, the characteristics of inductive spark are affected by flow velocity and by the existence of a flame. However, variations in the flow conditions do not affect the characteristics of the capacitive spark such as voltage-current time trace and energy deposition efficiency.
Two ignition systems using above mentioned two spark types were developed. First, the capacitive spark energy was directly deposited into the premixed flow. Most researchers have not concentrated on the early initiation process but on the flame growth. Therefore, the generated kernel formed by the energy deposition was observed and characterized using optical methods, immediately following the spark. In addition, the mixing effect for this ignition kernel with surrounding gas was simulated using a numerical method. Based on the time trace of the OH* chemiluminescence, the reaction starts with the discharge and it is continuous until combustion begins. This means that in the presence of a high density spark in premixed flow, there exists no traditional delay as defined by other researchers for auto ignition.
A simple Radical Jet Generator (RJG) was developed that is able to ignite and stabilize a flame in a high-speed flow. The inductive spark initiates the combustion in the RJG chamber. The RJG then injects the partially-burned products carrying large amounts of heat and radicals into a rapidly moving flammable main stream. Then it ignites and stabilizes a flame. The RJG requires low levels of electrical power as long as the flow velocity is relatively low since most of the radicals are produced by the incomplete combustion in its chamber. The importance of radicals was analyzed by RJG experiments and numerical methods. The reaction zone for RJG using a rich mixture was located both inside and outside of the RJG chamber. Therefore, the RJG using a rich mixture performed better in the ignition and stabilization of combustion in the main flow. According to an analysis using the CHEMKIM simulation software combined with the San Diego chemical mechanism, the RJG jet resulting from a rich mixture contains more radicals and intermediates than that produced by a lean mixture for the same sensible enthalpy. In addition, the burned gas contains less radicals and intermediates than the partially burned gas.
If the RJG is operating with a high speed main flow, the flow rate through the RJG chamber must be increased to allow the radical jet to penetrate well into the rapid flow due to their higher injection velocity. Unfortunately, this leads to unsteady combustion in the RJG, which results in the pulsation of the radical jet. This reduces the number of radicals injected into the main flow. To investigate this operating condition, special attention was focused on four possible factors: unburned reactant pockets caused by motion of the spark channel, spark frequency, flame propagation speed and ignition delay. It was shown that the unsteadiness is affected by the flame speed and ignition delay because the frequency of pulsation in the chamber is highly dependent on the equivalence ratio. In addition, the interaction between the RJG operation and the combustion dynamics in the main combustor was documented. The acoustic pressure oscillations in the main combustor were suppressed when the RJG jet was turned on because the reaction region is relocated by the operation of the RJG.
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Harnesk, Malin. "Att spara eller inte att inte spara? : En paneldatastudie över bestämningsfaktorer för hushållens sparkvot". Thesis, Umeå universitet, Nationalekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-118707.
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Karlsson, Robin. "Att spara eller inte spara : En jämförelsestudie i formmaterial vid gjutning av Prefab element". Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-21667.
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Syftet med denna studie är att undersöka för vilka byggen det är mer ekonomiskt lönsamt för leverantör av prefabelement att använda sig utav engångsskiva eller formplyfa som formmaterial. I uppdrag av UBAB har en undersökning gjorts om vilket formmaterial som är det lönsammare alternativet vid produktion av trappor. Detta har gjorts genom att analysera processernas tidåtgång, materialkostnad samt totalkostnad. Arbetssätten skiljer sig mellan de olika formmaterialen och därför har arbetsmomentet kartlagts genom tidsstudier för indata och observationer för ytterligare förståelse om processerna. Genom intervjuer har en materialåtgång framkommit som tillsammans med informationen från tidsstudierna använts för att ta fram totalkostnaden. Resultatet visar att totalkostnaden för engångsskivan är större än vid användandet av den traditionella formplyfan. Endast första gjutet visar sig vara lönsammare med engångsskivan. För att engångsskivan ska vara ett kostnadseffektivt alternativ vid flera gjut behövs materialåtgången sänkas då kostnaden för den snabbt blir dubbelt så dyr som med formplyfan. Även om kostnaden för engångsskivan är större finns fortfarande fördelar och möjligheter till förbättring. Att utveckla standardiserade arbetssätt även för engångsskivan kan göra det mer tidseffektivt och genom att få ner materialåtgången kan göra engångsskivan till ett mer lönsamt alternativ.The purpose of this study is to determent what type of build it’s more economic profitable for the supplier of prefab element to use single-use sheets or form plywood as mold material. Tasked by UBAB a survey was made to see which of the mold materials’ the most profitable alternative in production of stairs. This was made through analyzing the processes time consumption, material cost and total cost. Working procedure is different between the mold materials and that is why the operations been charted through time studies for input and observations for a greater understanding of the processes. A material consumption has emerged through interviews that together with the information from the time studies been used to determent the total cost. The result shows that the total cost for the single-use sheet is greater than when using the traditional form plywood. Only the first cast turns out to be more profitable with the single-use sheet. For the single-use sheet to be a cost efficient alternative at multiple casts the material consumption must be lowered since the cost quickly becomes twice as expensive as form plywood. Even though the cost of single-use sheets is greater there are still benefits and possibilities for improvement. To develop standardized working procedures for the single-use sheet as well could make it more time efficient and by decreasing the material consumption could make the single-use sheet a more profitable alternative.
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Wolfe, Adam J. "5-sparse steiner triple systems". Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1122922255.
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Thesis (Ph. D.)--Ohio State University, 2005.Title from first page of PDF file. Document formatted into pages; contains xi, 196 p.; also includes graphics. Includes bibliographical references (p. 195-196). Available online via OhioLINK's ETD Center
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Grădinaru, Vasile Catrinel. "Whitney elements on sparse grids". [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=964889897.
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Thom, Markus [Verfasser]. "Sparse neural networks / Markus Thom". Ulm : Universität Ulm. Fakultät für Ingenieurwissenschaften und Informatik, 2015. http://d-nb.info/1067496319/34.
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Selén, Yngve. "Model selection and sparse modeling /". Uppsala : Department of Information Technology, Uppsala University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8202.
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Ni, Ze. "Comparative Evaluation of Spark andStratosphere". Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-118226.
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Nowadays, although MapReduce is applied to the parallel processing on big data, it has some limitations: for instance, lack of generic but efficient and richly functional primitive parallel methods, incapability of entering multiple input parameters on the entry of parallel methods, and inefficiency in the way of handling iterative algorithms. Spark and Stratosphere are developed to deal with (partly) the shortcoming of MapReduce. The goal of this thesis is to evaluate Spark and Stratosphere both from the point of view of theoretical programming model and practical execution on specified application algorithms. In the introductory section of comparative programming models, we mainly explore and compare the features of Spark and Stratosphere that overcome the limitation of MapReduce. After the comparison in theoretical programming model, we further evaluate their practical performance by running three different classes of applications and assessing usage of computing resources and execution time. It is concluded that Spark has promising features for iterative algorithms in theory but it may not achieve the expected performance improvement to run iterative applications if the amount of memory used for cached operations is close to the actual available memory in the cluster environment. In that case, the reason for the poor results in performance is because larger amount of memory participates in the caching operation and in turn, only a small amount memory is available for computing operations of actual algorithms. Stratosphere shows favorable characteristics as a general parallel computing framework, but it has no support for iterative algorithms and spends more computing resources than Spark for the same amount of work. In another aspect, applications based on Stratosphere can achieve benefits by manually setting compiler hints when developing the code, whereas Spark has no corresponding functionality.
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Subhan, Fazli. "Multilevel sparse kernel-based interpolation". Thesis, University of Leicester, 2011. http://hdl.handle.net/2381/9894.
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Radial basis functions (RBFs) have been successfully applied for the last four decades for fitting scattered data in Rd, due to their simple implementation for any d. However, RBF interpolation faces the challenge of keeping a balance between convergence performance and numerical stability. Moreover, to ensure good convergence rates in high dimensions, one has to deal with the difficulty of exponential growth of the degrees of freedom with respect to the dimension d of the interpolation problem. This makes the application of RBFs limited to few thousands of data sites and/or low dimensions in practice. In this work, we propose a hierarchical multilevel scheme, termed sparse kernel-based interpolation (SKI) algorithm, for the solution of interpolation problem in high dimensions. The new scheme uses direction-wise multilevel decomposition of structured or mildly unstructured interpolation data sites in conjunction with the application of kernel-based interpolants with different scaling in each direction. The new SKI algorithm can be viewed as an extension of the idea of sparse grids/hyperbolic cross to kernel-based functions. To achieve accelerated convergence, we propose a multilevel version of the SKI algorithm. The SKI and multilevel SKI (MLSKI) algorithms admit good reproduction properties: they are numerically stable and efficient for the reconstruction of large data in Rd, for d = 2, 3, 4, with several thousand data. SKI is generally superior over classical RBF methods in terms of complexity, run time, and convergence at least for large data sets. The MLSKI algorithm accelerates the convergence of SKI and has also generally faster convergence than the classical multilevel RBF scheme.
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Chan, Vincent. "Finite configurations in sparse sets". Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/46365.
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We prove a result which adds to the study of continuous analogues of Szemerédi-type problems. Let E ⊆ ℝⁿ be a Lebesgue-null set of Hausdorff dimension α, k, m be integers satisfying a suitable relationship, and {B₁,…, Bk} be n × (m − n) matrices. We prove that if the set of matrices Bi are non-degenerate in a particular sense, α is sufficiently close to n, and if E supports a probability measure satisfying certain dimensionality and Fourier decay conditions, then E contains a k-point configuration of the form {x + B₁y,…,x + Bky}. In particular, geometric configurations such as collinear triples, triangles, and parallelograms are contained in sets satisfying the above conditions.
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Lind, Tommy. "Schools in sparse spatial structures". Licentiate thesis, Umeå universitet, Institutionen för geografi och ekonomisk historia, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-143192.
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This thesis describes and analyses how the school sector in sparsely populated municipalities in northern Sweden has developed with emphasis on spatial dimensions and in relation to demographic change and political reforms during the last 20 years. In paper I primary schools were studied in a number of small municipalities in the northern parts of Norway, Sweden, and Finland. The aim of the study was to investigate how the spatial structure of schools has changed, what strategies the municipalities have developed to adapt their schools to changing conditions and what constraints there are to apply the strategies. To answer these questions, semi-structured interviews with municipal representatives were conducted. In paper II, the upper secondary school system was studied. The aim of the paper was to analyse the combined consequences of the school reforms, demographic development and competition on the ability of small municipalities to provide upper secondary schools during the period 1997 to 2015 in the four northernmost counties of Sweden. The study was based on data from the database SIRIS at the Swedish National Agency for Education and has a descriptive approach. The spatial structure of school organizations under study has undergone substantial changes during the recent decades, with closures and mergers among primary schools and an expansion of upper secondary schools. In recent years, the size of the young cohorts have decreased, which overall has led to increasing pressures to close primary schools and has created a detrimental competition between upper secondary schools. The large distances and the already small and declining number of pupils have had major effects on the ability to offer a good range and quality in the supply and availability of education. According to representatives from all the studied municipalities, the ambition is to prioritize the primary schools in the municipal centre and have as few small village schools as possible, taking into consideration quality of education, per capita costs, distances, and how scattered the pupils are within the municipalities. Independent schools and their increasingly larger role have attracted a great deal of attention in media, but this is a change that has mainly occurred in municipalities with large populations and their presence in the studied municipalities is very small both at the primary and upper secondary level.
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Zhang, Yuan Ph D. Massachusetts Institute of Technology. "Parsing with sparse annotated resources". Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/82180.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2013.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (p. 67-73).
This thesis focuses on algorithms for parsing within the context of sparse annotated resources. Despite recent progress in parsing techniques, existing methods require significant resources for training. Therefore, current technology is limited when it comes to parsing sentences in new languages or new grammars. We propose methods for parsing when annotated resources are limited. In the first scenario, we explore an automatic method for mapping language-specific part of- speech (POS) tags into a universal tagset. Universal tagsets play a crucial role in cross-lingual syntactic transfer of multilingual dependency parsers. Our central assumption is that a high-quality mapping yields POS annotations with coherent linguistic properties which are consistent across source and target languages. We encode this intuition in an objective function. Given the exponential size of the mapping space, we propose a novel method for optimizing the objective over mappings. Our results demonstrate that automatically induced mappings rival their manually designed counterparts when evaluated in the context of multilingual parsing. In the second scenario, we consider the problem of cross-formalism transfer in parsing. We are interested in parsing constituency-based grammars such as HPSG and CCG using a small amount of data annotated in the target formalisms and a large quantity of coarse CFG annotations from the Penn Treebank. While the trees annotated in all of the target formalisms share a similar basic syntactic structure with the Penn Treebank CFG, they also encode additional constraints and semantic features. To handle this apparent difference, we design a probabilistic model that jointly generates CFG and target formalism parses. The model includes features of both parses, enabling transfer between the formalisms, and preserves parsing efficiency. Experimental results show that across a range of formalisms, our model benefits from the coarse annotations.
by Yuan Zhang.
S.M.
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Price, Eric C. "Sparse recovery and Fourier sampling". Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/85458.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2013.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 155-160).
In the last decade a broad literature has arisen studying sparse recovery, the estimation of sparse vectors from low dimensional linear projections. Sparse recovery has a wide variety of applications such as streaming algorithms, image acquisition, and disease testing. A particularly important subclass of sparse recovery is the sparse Fourier transform, which considers the computation of a discrete Fourier transform when the output is sparse. Applications of the sparse Fourier transform include medical imaging, spectrum sensing, and purely computation tasks involving convolution. This thesis describes a coherent set of techniques that achieve optimal or near-optimal upper and lower bounds for a variety of sparse recovery problems. We give the following state-of-the-art algorithms for recovery of an approximately k-sparse vector in n dimensions: -- Two sparse Fourier transform algorithms, respectively taking ... time and ... samples. The latter is within log e log n of the optimal sample complexity when ... -- An algorithm for adaptive sparse recovery using ... measurements, showing that adaptivity can give substantial improvements when k is small. -- An algorithm for C-approximate sparse recovery with ... measurements, which matches our lower bound up to the log* k factor and gives the first improvement for ... In the second part of this thesis, we give lower bounds for the above problems and more.
by Eric Price.
Ph. D.
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Naish-Guzman, Andrew Guillermo Peter. "Sparse and robust kernel methods". Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612420.
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Usta, Fuat. "Sparse grid approximation with Gaussians". Thesis, University of Leicester, 2015. http://hdl.handle.net/2381/33295.
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Motivated by the recent multilevel sparse kernel-based interpolation (MuSIK) algorithm proposed in [Georgoulis, Levesley and Subhan, SIAM J. Sci. Comput., 35(2), pp. A815-A831, 2013], we introduce the new quasi-multilevel sparse interpolation with kernels (Q-MuSIK) via the combination technique. The Q-MuSIK scheme achieves better convergence and run time in comparison with classical quasi-interpolation; namely, the Q-MuSIK algorithm is generally superior to the MuSIK methods in terms of run time in particular in high-dimensional interpolation problems, since there is no need to solve large algebraic systems. We subsequently propose a fast, low complexity, high-dimensional quadrature formula based on Q-MuSIK interpolation of the integrand. We present the results of numerical experimentation for both interpolation and quadrature in Rd, for d = 2, d = 3 and d = 4. In this work we also consider the convergence rates for multilevel quasiinterpolation of periodic functions using Gaussians on a grid. Initially, we have given the single level quasi-interpolation error by using the shifting properties of Gaussian kernel, and have then found an estimate for the multilevel error using the multilevel algorithm for unit function.
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Kandola, Jasvinder S. "Interpretable modelling with sparse kernels". Thesis, University of Southampton, 2001. https://eprints.soton.ac.uk/256087/.
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Bútora, Matúš. "Modelem řízený vývoj Spark úloh". Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2019. http://www.nusl.cz/ntk/nusl-403168.
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The aim of the master thesis is to describe Apache Spark framework , its structure and the way how Spark works . Next goal is to present topic of Model- Driven Development and Model-Drive Architecture . Define their advantages , disadvantages and way of usage . However , the main part of this text is devoted to design a model for creating tasks in Apache Spark framework . Text desribes application , that allows user to create graph based on proposed modeling language . Final application allows user to generate source code from created model.