Spelling suggestions: "subject:"correlogram"" "subject:"korrelogram""
1 |
Spatial Variability of shotcrete thicknessKlaube, Maximilian January 2018 (has links)
An important task during the construction process is to validate the dimensions and properties of a given structure. The dimensions like for instance the thickness of a construction element should be measured after finishing building it. The aim is to compare the measured value with the design value to avoid that elements do not correspond to the input requirements. Moreover, the measurements are helpful to analyse the statistical distribution of the investigated geometrical property by computing e.g. a histogram, which visualises the dispersion and enable the calculation of the probability of failure for a specific structure or element.In this work, a shotcrete layer has been analysed in order to provide information about the homogeneity of the shotcrete thickness in a pre-determined tunnel section. The calculation method is based on two laser scans, before and after applying the shotcrete. Due to the construction process, the shotcrete layer will not be totally equal, which might be a safety problem. Especially, when the shotcrete layer is thinner than required and hence, the actual variation of the shotcrete must be considered and verified.To determine the statistical distribution, correlograms and histograms have been computed for a wall area in a tunnel in Southern Sweden. The correlogram shows the distance where the values have a correlation to each other and usually this distance is called scale of fluctuation. For the wall section, this scale of fluctuation has been calculated for the length (0.8m) as well as the height (0.8m). Compared to the original sample distance, e.g. distance of the rock bolts, the variance for the calculation of the probability of failure might be reduced.
|
2 |
A Survays On Fading Channel Over West - Java Area for Flight Test Radio Telemetering PurposesSoelaiman, Adi Dharma, Pudjiastuti, Rina 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1988 / Riviera Hotel, Las Vegas, Nevada / This paper discusses one approach to determine a characteristic of West - Java's air and ground segment as a block-box to accomodate radio waves propagation, especially in L-band ranges, by evaluating both the topographical data and radio reception pattern as measured from ground based telemetry receiving-end system. All the measured signals are random and assumed to be stationair and ergodic. In order to characterize the channel for polarization diversity reception, some statistical analysis are applied to the signal strength measured of both - RHCP and LHCP components of 1531 MHz propagated waves as transmitted fr om NC212-200 PK-NZJ-aircraft. Some computer calculated correlograms of measured data are shown herewith, it is focused for a certain radio corridor at radial 265E relative to the ground based receiving antenna. More over some curves of predicted multipath gain factor are also presented to gain more theoretical back ground. When this paper is written, a further field experiments on the matter concerned is beeing conducted.
|
3 |
Detecção automática de massas em mamografias digitais usando Quality Threshold clustering e MVS / Automatic mass detection on digital mammography using Quality Threshold clustering and MVSSILVA, Joberth de Nazaré 20 February 2013 (has links)
Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-08-16T18:29:06Z
No. of bitstreams: 1
JoberthSilva.pdf: 6383640 bytes, checksum: f18918eb45c49cb426b560e4daddf994 (MD5) / Made available in DSpace on 2017-08-16T18:29:06Z (GMT). No. of bitstreams: 1
JoberthSilva.pdf: 6383640 bytes, checksum: f18918eb45c49cb426b560e4daddf994 (MD5)
Previous issue date: 2013-02-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Breast cancer is worldwide the most common form of cancer affecting woman, sometimes in
their lives, at the proportion of either one to nine or one to thirteen women who reach the age
of ninety in the west world (LAURENCE, 2006). Breast cancer is caused by frequent
reproduction of cells in various parts of the human body. At certain times, and for reasons yet
unknown, some cells begin to reproduce at a higher speed, causing the onset of cellular
masses called neoplasias, or tumors, which are new tissue formation, but from pathological
origin. This work has proposed a method of automatic detection of masses in digital
mammograms, using the Quality Threshold (QT), and the Supporting Vector Machine
(MVS). The images processing steps were as follows: firstly, the pre-processing phase took
place which consisted of removing the background image, smoothing it with a low pass filter,
to increase the degree of contrast, and then, in sequence, accomplishing an enhancement of
the Wavelet Transform (WT) by changing their coefficients with a linear function. After the
pre-processing phase, came the segmentation with the use of the QT which divided the image
in to clusters with pre-defined diameters. Then, the post-processing occurred with the
selection of the best candidates to mass formed by the MVS analysis of the shape descriptors.
For the extraction phase of texture features the Haralick descriptors and the function
correlogram were used. As for the classification stage, the MVS was used again for training,
validation of the MVS model and final test. The achieved results were: sensitivity of 92. 31%,
specificity of 82.2%, accuracy of 83,53%, a false positive rate per image of 1.12 and an area
under a FROC curve of 0.8033. / O câncer de mama é, mundialmente, a forma mais comum de câncer em mulheres afetando,
em algum momento suas vidas, aproximadamente uma em cada nove a uma em cada treze
mulheres que atingem os noventa anos no mundo ocidental (LAURANCE, 2006). O câncer
de mama é ocasionado pela reprodução frequente de células de diversas partes do corpo
humano. Em certos momentos e por motivos ainda desconhecidos algumas células começam a
se reproduzir com uma velocidade maior, ocasionando o surgimento de massas celulares
denominadas de neoplasias ou tumores que são tecidos de formação nova, mas de origem
patológica. Neste trabalho foi proposto um método de detecção automática de massas em
mamografias digitais usando o Quality Threshold (QT), e a Máquina de Vetores de Suporte
(MVS). As etapas de processamento das imagens foram as seguintes: primeiramente veio a
fase de pré-processamento que consiste em retirar o fundo da imagem, suavizá-la com um
filtro passa-baixa, aumentar a escala de contraste, e na sequencia realizar um realce com a
Transformada de Wavelet (WT) através da alteração dos seus coeficientes com uma função
linear. Após a fase de pré-processamento vem a seguimentação utilizando o QT que segmenta
a imagem em clusters com diâmetros pré-definidos. Em seguida, vem o pós-processamento
com a seleção dos melhores candidatos à massa feita através da análise dos descritores de
forma pela MVS. Para fase de extração de características de textura foram utiliza os
descritores de Haralick e a função correlograma. Já na fase de classificação a MVS
novamente foi utilizada para o treinamento, validação do modelo MVS e teste final. Os
resultados alcançados foram: sensibilidade de 92,31%, especificidade de 82,2%, Acurácia de
83,53%, uma taxa de falsos positivos por imagem de 1,12 e uma área sob a curva FROC de
0,8033.
|
4 |
Computer methods for voice analysisGranqvist, Svante January 2003 (has links)
This thesis consists of five articles and a summary. Thethesis deals with methods for measuring properties of thevoice. The methods are all computer-based, but utilisedifferent approaches for measuring different aspects of thevoice. Paper I introduces the Visual Sort and Rate (VSR) method forperceptual rating of voice quality. The method is based on theVisual Analogue Scale (VAS), but simultaneously shows allstimuli as icons along the VAS on the computer screen. As thelistener places similar-sounding stimuli close to each otherduring the rating process, comparing stimuli becomeseasier. Paper II introduces the correlogram. Fundamental frequencyF0 sometimes cannot be strictly defined, particularly forperturbed voice signals. The method displays multipleconsecutive correlation functions in a grey scale image. Thus,the correlogram avoids selecting a single F0 value. Rather itpresents an unbiased image of periodicity, allowing theinvestigator to select among several candidates, ifappropriate. PaperIII introduces a method for detection of phonation tobe utilised in voice accumulators. The method uses twomicrophones attached near the subjects ears. Phase andamplitude relations of the microphone signals are used to forma phonation detector. The output of the method can be used tomeasure phonation time, speaking time and fundamental frequencyof the subject, as well as sound pressure level of both thesubjects voicing and the ambient sounds. Paper IV introduces a method for Fourier analysis ofhigh-speed laryngoscopic imaging. The data from the consecutiveimages are re-arranged to form time-series that reflect thetime-variation of light intensity in each pixel. Each of thesetime series is then analysed by means of Fouriertransformation, such that a spectrum for each pixel isobtained. Several ways of displaying these spectra aredemonstrated. Paper V examines a test set-up for simultaneous recording ofairflow, intra-oral pressure, electro-glottography, audio andhigh-speed imaging. Data are analysed with particular focus onsynchronisation between glottal area and inverse filteredairflow. Several methodological aspects are also examined, suchas the difficulties in synchronising high-speed imaging datawith the other signals. / QC 20100609
|
5 |
Metric Based Automatic Event Segmentation and Network Properties Of Experience GraphsZhuang, Yuwen 22 June 2012 (has links)
No description available.
|
6 |
Pitch tracking and speech enhancement in noisy and reverberant environmentsWu, Mingyang 07 November 2003 (has links)
No description available.
|
Page generated in 0.0568 seconds