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Syntax in methods for information retrieval
Straková, Jana
Title: Information Retrieval Using Syntax Information Author: Bc. Jana Kravalová Department: Institute of Formal and Applied Linguistics Supervisor: Mgr. Pavel Pecina, Ph.D. Supervisor's e-mail address: pecina@ufal.mff.cuni.cz Abstract: In the last years, application of language modeling in infor- mation retrieval has been studied quite extensively. Although language models of any type can be used with this approach, only traditional n-gram models based on surface word order have been employed and described in published experiments (often only unigram language models). The goal of this thesis is to design, implement, and evaluate (on Czech data) a method which would extend a language model with syntactic information, automatically obtained from documents and queries. We attempt to incorporate syntactic information into language models and experimentally compare this approach with uni- gram and bigram model based on surface word order. We also empirically compare methods for smoothing, stemming and lemmatization, effectiveness of using stopwords and pseudo relevance feedback. We perform a detailed ana- lysis of these retrieval methods and describe their performance in detail. Keywords: information retrieval, language modelling, depenency syntax, smo- othing
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3D Triangles Polygonal Mesh Conversion on 3D Spline Surfaces
Jahn, Zdeněk ; Španěl, Michal (referee) ; Kršek, Přemysl (advisor)
This bachelor's thesis deals with the problem of the remeshing of unstructured triangular 3D meshes to more suitable representations ( quadrilateral meshes or spline surfaces ). It explains the basic problems related with the unstructured meshes and the reasons for its solution. It classifies the usable methods, describes the most suitable candidates briefly. It follows the chosen method in detail - both the theoretical matter and the specific implementation.
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Polygonal Models Smoothing
Svěchovský, Radek ; Švub, Miroslav (referee) ; Kršek, Přemysl (advisor)
Object digitizing or 3D model transformation into surface representation brings defects in the form of noise. This thesis analyses the well-known approaches to the noise elimination from polygonal models. The reader will be concerned with the fundamental principles of smoothing and foremost the results of the comparison of different methods including Laplace method, algorithm Laplace-HC, Taubin's low-pass filter and bilateral filter.
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Mining of Textual Data from the Web for Speech Recognition
Kubalík, Jakub ; Plchot, Oldřich (referee) ; Mikolov, Tomáš (advisor)
Prvotním cílem tohoto projektu bylo prostudovat problematiku jazykového modelování pro rozpoznávání řeči a techniky pro získávání textových dat z Webu. Text představuje základní techniky rozpoznávání řeči a detailněji popisuje jazykové modely založené na statistických metodách. Zvláště se práce zabývá kriterii pro vyhodnocení kvality jazykových modelů a systémů pro rozpoznávání řeči. Text dále popisuje modely a techniky dolování dat, zvláště vyhledávání informací. Dále jsou představeny problémy spojené se získávání dat z webu, a v kontrastu s tím je představen vyhledávač Google. Součástí projektu byl návrh a implementace systému pro získávání textu z webu, jehož detailnímu popisu je věnována náležitá pozornost. Nicméně, hlavním cílem práce bylo ověřit, zda data získaná z Webu mohou mít nějaký přínos pro rozpoznávání řeči. Popsané techniky se tak snaží najít optimální způsob, jak data získaná z Webu použít pro zlepšení ukázkových jazykových modelů, ale i modelů nasazených v reálných rozpoznávacích systémech.
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Prediction of Time Series Using Statistical Methods
Beluský, Ondrej ; Bidlo, Michal (referee) ; Schwarz, Josef (advisor)
Many companies consider essential to obtain forecast of time series of uncertain variables that influence their decisions and actions. Marketing includes a number of decisions that depend on a reliable forecast. Forecasts are based directly or indirectly on the information derived from historical data. This data may include different patterns - such as trend, horizontal pattern, and cyclical or seasonal pattern. Most methods are based on the recognition of these patterns, their projection into the future and thus create a forecast. Other approaches such as neural networks are black boxes, which uses learning.
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Processing of 3D Scene Models
Zdráhal, Lukáš ; Chudý, Peter (referee) ; Zemčík, Pavel (advisor)
Purpose of this document is acquite reader with basic principles of 3D model digitalization.This work describes general overview of 3D scanning devices, their physical principle and measurements methods. Next part of this document describes basic method for polygonal mesh processing as smoothing an decimation which are necessary for 3D model processing.This document contains also algorithms description of implementation, user interface and publication part through WWW. Fundamental essence of this diploma thesis will be introduction with general principles of 3D scanning and working with Minolta VIVID-700 3D digitizer which is placed on our faculty. At the end are mentioned results evalution,demostration examples and next supposed project advancement.
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Tooth Detection on Jaw 3D Computer Polygonal Model
Hulík, Rostislav ; Španěl, Michal (referee) ; Kršek, Přemysl (advisor)
This document discusses a concept and implementation of algorithms for teeth detection on 3D polygonal jaw model. At first, I describe possible shape detection techniques on three dimensional computer model, including utilization just in my case. After it, I analyze filtration problems of obtained model segments in order to reliably separate regions of tooth-arch from the rest of jaw. I included all these pieces of knowledge into a final application. Here, it is possible to choose from two user interfaces, first, classic user interface which demonstrates possible utilization in real world and second, testing interface which demonstrates functions of each detection and filtration method used in program and their effect on detection. Application is written in C++ language in development environment of MS Visual Studio 2005 and compiled with MS VS internal compiler. Tested was under MS Windows XP and MS Windows Vista OS.
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Creating 3D Model of Temporomandibular Joint
Šmirg, Ondřej ; Bartušek, Karel (referee) ; Liberda,, Ondřej (referee) ; Smékal, Zdeněk (advisor)
The dissertation thesis deals with 3D reconstruction of the temporomandibular joint from 2D slices of tissue obtained by magnetic resonance. The current practice uses 2D MRI slices in diagnosing. 3D models have many advantages for the diagnosis, which are based on the knowledge of spatial information. Contemporary medicine uses 3D models of tissues, but with the temporomandibular joint tissues there is a problem with segmenting the articular disc. This small tissue, which has a low contrast and very similar statistical characteristics to its neighborhood, is very complicated to segment. For the segmentation of the articular disk new methods were developed based on the knowledge of the anatomy of the joint area of the disk and on the genetic-algorithm-based statistics. A set of 2D slices has different resolutions in the x-, y- and z-axes. An up-sampling algorithm, which seeks to preserve the shape properties of the tissue was developed to unify the resolutions in the axes. In the last phase of creating 3D models standard methods were used, but these methods for smoothing and decimating have different settings (number of polygons in the model, the number of iterations of the algorithm). As the aim of this thesis is to obtain the most precise model possible of the real tissue, it was necessary to establish an objective method by which it would be possible to set the algorithms so as to achieve the best compromise between the distortion and the model credibility achieve.
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3D data
Klusáček, Jan ; Janáková, Ilona (referee) ; Richter, Miloslav (advisor)
The goal of this thesis is to design methods for acquisition of three dimensional model of object using illumination by laser streak which is read by camera. The first part describes theoretical principle and points out some problems which are linked to this method. Followed by description of interfaces which can be used for acquisition of image from camera. Next part is focused on more detailed description of DirectShow interface which is used in this thesis. Description of concrete methods designated for processing acquired image, calibration and composition of three dimensional model are also topics of this work. The Last part describes device which was created to verificate and automatize designed methods.
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