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Estimação de estados de distorções harmônicas em sistemas elétricos de potência utilizando estratégias evolutivas.; Power systems harmonic distortion state estimation using evolutionary strategy.

Arruda, Elcio Franklin de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 11/06/2008 PT
Relevância na Pesquisa
36.13%
Esta teste de doutorado tem como objetivo o desenvolvimento de um algoritmo de Estimação de Estados de Distorções Harmônicas (EEDH) em Sistemas Elétricos de Potência. Embora o custo dos medidores de qualidade de energia tenha diminuído, ainda é inviável a utilização de medidores para a monitoração de todas as barras de um sistema elétrico real, pois o sistema de monitoração tornar-se-ia demasiadamente oneroso. Sendo assim, torna-se necessária à utilização de algoritmo capaz de estimar, a partir de um pequeno número de pontos de monitoração, os valores das distorções harmônicas em demais pontos do sistema. Para resolver o problema em estudo, propõe-se a utilização de algoritmo de Estratégias Evolutivas. Tal algoritmo se mostra viável por sua facilidade de implementação e sua velocidade em encontrar uma solução dentro de um vasto espaço de soluções. Neste contexto, uma solução para o problema de estimação compreende um indivíduo que pode sofrer mutação e recombinação, sendo este avaliado a cada geração do algoritmo. A avaliação de cada indivíduo esta relacionada à minimização do erro quadrático de estimação de tensões nas barras monitoradas do sistema. Para esta realização são utilizadas as informações das distorções provenientes de medidores...

Análise geográfica computadorizada na estimativa de qualidade ambiental para mamíferos de médio e grande porte; Computerized geographic analysis on habitat quality estimation for medium and large-sized mammals

Martins, Iris Amati
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 22/09/2009 PT
Relevância na Pesquisa
45.87%
A intensa degradação do bioma cerrado tem tido grandes conseqüências na disponibilidade de habitats de boa qualidade para muitos animais e a busca por métodos rápidos e confiáveis que localizem áreas de valor ecológico para diferentes grupos de animais tem despertado grande interesse. A análise geográfica computadorizada foi utilizada como ferramenta para caracterização da heterogeneidade (diversos graus de qualidade e tipo de cobertura fitofisionômica) dos habitats existentes no remanescente estudado, buscando fornecer informações que pudessem levar ao entendimento de como as espécies de mamíferos de médio e grande porte utilizam estes habitats alterados, além de fornecer informações que pudessem ser utilizadas para o delineamento da amostragem. Desta forma, a primeira etapa foi a elaboração de uma base cartográfica que produziu dois mapas de caracterização ambiental, um mapa geral e outro da mata ripária. O primeiro foi utilizado para a realização de uma análise preliminar da qualidade dos habitats e distribuição das armadilhas fotográficas, transecções e canteiros de pegadas, buscando capturar toda a heterogeneidade existente no remanescente. Desta forma, houve a sistematização das amostragens. A utilização destes métodos permitiu a detecção de 22 espécies de mamíferos de médio e grande porte em 28 dias de amostragem...

Estimativa de qualidade de impressões digitais utilizando Sistemas de Inferência Fuzzy; Fingerprint quality estimation using Fuzzy Inference Systems

Tada, Carlos Henrique Moniwa
Fonte: Universidade de Brasília Publicador: Universidade de Brasília
Tipo: Dissertação
POR
Relevância na Pesquisa
46.01%
Dissertação (Mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Elétrica, 2011.; A qualidade da imagem de impressões digitais influencia o desempenho de sistemas automáticos de reconhecimento de impressões digitais, tais como o AFIS. Este trabalho propõe um esquema híbrido para estimativa de qualidade de imagens de impressão digital usando medidas de características locais (contraste, curvatura, fluxo de cristas papilares) e globais (área e espectro de potência no domínio da frequência). Sistemas de inferência fuzzy são usados para combinação dessas medidas e obtenção de uma pontuação de qualidade. São feitos testes usando imagens de impressões digitais das bases de dados DB2-A e DB4-A do Fingerprint Verification Competition 2006 (FVC 2006) e o programa de identificação de digitais BOZORTH3 do NIST Biometric Image Software (NBIS). É feita uma comparação do desempenho do método proposto com o programa NFIQ. Com a remoção de 5%, 10% e 15% das impressões digitais de pior qualidade da base DB2-A, obteve-se uma melhora no EER (equal error rate) de 14,4%, 29,4% e 46,6%, respectivamente. Para a DB4-A...

Preservation technologies towards improvement of fresh whole tomato fruits quality

Pinheiro, Maria Joaquina da Cunha
Fonte: Universidade Católica Portuguesa Publicador: Universidade Católica Portuguesa
Tipo: Tese de Doutorado
Publicado em 10/11/2014 ENG
Relevância na Pesquisa
45.93%
O tomate (Solanum lycopersicum) é um dos frutos mais consumidos no mundo e com um papel relevante na saúde do consumidor devido à sua riqueza em vitaminas, licopeno, fibras e compostos fenólicos. Os desafios que se colocam aos produtores e indústria de tomate em fresco são o de manter a qualidade e prolongar o seu período de vida útil. Tecnologias de pós-colheita alternativas e emergentes, tais como o tratamento térmico (WHT), ultrassons (US), termossonicação (TS) e radiação ultravioleta (UV-C), têm sido testados em diferentes frutos e vegetais de forma a minimizar as perdas de qualidade sensorial e nutricional com reduzida utilização de aditivos químicos. Nesta dissertação, foram demonstradas as vantagens da aplicação destas tecnologias alternativas na manutenção da qualidade do tomate em fresco (cv. Zinac) durante o período logístico de armazenamento. A avaliação da qualidade do tomate foi realizada através de parâmetros físico-químicos (cor CIELab, textura, pH, teor de sólidos solúveis, perda de peso), sensoriais (cor, índice de deterioração e aceitabilidade global), bioquímicos (atividade enzimática da peroxidase: POD, e pectinametilesterase: PME), bioativos (conteúdo fenólico total e capacidade antioxidante)...

Procedures for estimation of modelling uncertainty in air quality assessment

Borrego, C.; Monteiro, A.; Ferreira, J.; Miranda, A. I.; Costa, A. M.; Carvalho, A. C.; Lopes, M.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.12%
The main objectives of this work focus, firstly, on a review of the current existent methodologies to estimate air quality modelling uncertainty, and, secondly, in the preparation of guidelines for modelling uncertainty estimation, which can be used by local and regional authorities responsible for air quality management. From the application exercise, it was concluded that it is possible to define a subset of statistical parameters able to reproduce the general uncertainties estimation. Concerning the quality indicators defined by EU directives, the results show that the legislated uncertainty estimation measures are ambiguous and inadequate in several aspects, mainly in what concerns the error measures for hourly and daily indicators based on the highest observed concentration. A relative error at the percentile correspondent to the allowed number of exceedances of the limit value was suggested and tested, showing that is a more robust and appropriate parameter for model performance evaluation.

Review: computer vision applied to the inspection and quality control of fruits and vegetables

Saldaña,Erick; Siche,Raúl; Luján,Mariano; Quevedo,Roberto
Fonte: Instituto de Tecnologia de Alimentos - ITAL Publicador: Instituto de Tecnologia de Alimentos - ITAL
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2013 EN
Relevância na Pesquisa
45.83%
This is a review of the current existing literature concerning the inspection of fruits and vegetables with the application of computer vision, where the techniques most used to estimate various properties related to quality are analyzed. The objectives of the typical applications of such systems include the classification, quality estimation according to the internal and external characteristics, supervision of fruit processes during storage or the evaluation of experimental treatments. In general, computer vision systems do not only replace manual inspection, but can also improve their skills. In conclusion, computer vision systems are powerful tools for the automatic inspection of fruits and vegetables. In addition, the development of such systems adapted to the food industry is fundamental to achieve competitive advantages.

QMEAN server for protein model quality estimation

Benkert, Pascal; Künzli, Michael; Schwede, Torsten
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
45.97%
Model quality estimation is an essential component of protein structure prediction, since ultimately the accuracy of a model determines its usefulness for specific applications. Usually, in the course of protein structure prediction a set of alternative models is produced, from which subsequently the most accurate model has to be selected. The QMEAN server provides access to two scoring functions successfully tested at the eighth round of the community-wide blind test experiment CASP. The user can choose between the composite scoring function QMEAN, which derives a quality estimate on the basis of the geometrical analysis of single models, and the clustering-based scoring function QMEANclust which calculates a global and local quality estimate based on a weighted all-against-all comparison of the models from the ensemble provided by the user. The web server performs a ranking of the input models and highlights potentially problematic regions for each model. The QMEAN server is available at http://swissmodel.expasy.org/qmean.

Effective Fingerprint Quality Estimation for Diverse Capture Sensors

Xie, Shan Juan; Yoon, Sook; Shin, Jinwook; Park, Dong Sun
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: Artigo de Revista Científica
Publicado em 26/08/2010 EN
Relevância na Pesquisa
45.99%
Recognizing the quality of fingerprints in advance can be beneficial for improving the performance of fingerprint recognition systems. The representative features to assess the quality of fingerprint images from different types of capture sensors are known to vary. In this paper, an effective quality estimation system that can be adapted for different types of capture sensors is designed by modifying and combining a set of features including orientation certainty, local orientation quality and consistency. The proposed system extracts basic features, and generates next level features which are applicable for various types of capture sensors. The system then uses the Support Vector Machine (SVM) classifier to determine whether or not an image should be accepted as input to the recognition system. The experimental results show that the proposed method can perform better than previous methods in terms of accuracy. In the meanwhile, the proposed method has an ability to eliminate residue images from the optical and capacitive sensors, and the coarse images from thermal sensors.

A Multivariate Model for Coastal Water Quality Mapping Using Satellite Remote Sensing Images

Su, Yuan-Fong; Liou, Jun-Jih; Hou, Ju-Chen; Hung, Wei-Chun; Hsu, Shu-Mei; Lien, Yi-Ting; Su, Ming-Daw; Cheng, Ke-Sheng; Wang, Yeng-Fung
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: Artigo de Revista Científica
Publicado em 10/10/2008 EN
Relevância na Pesquisa
36.15%
This study demonstrates the feasibility of coastal water quality mapping using satellite remote sensing images. Water quality sampling campaigns were conducted over a coastal area in northern Taiwan for measurements of three water quality variables including Secchi disk depth, turbidity, and total suspended solids. SPOT satellite images nearly concurrent with the water quality sampling campaigns were also acquired. A spectral reflectance estimation scheme proposed in this study was applied to SPOT multispectral images for estimation of the sea surface reflectance. Two models, univariate and multivariate, for water quality estimation using the sea surface reflectance derived from SPOT images were established. The multivariate model takes into consideration the wavelength-dependent combined effect of individual seawater constituents on the sea surface reflectance and is superior over the univariate model. Finally, quantitative coastal water quality mapping was accomplished by substituting the pixel-specific spectral reflectance into the multivariate water quality estimation model.

LQER: A Link Quality Estimation based Routing for Wireless Sensor Networks

Chen, Jiming; Lin, Ruizhong; Li, Yanjun; Sun, Youxian
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: Artigo de Revista Científica
Publicado em 15/02/2008 EN
Relevância na Pesquisa
45.94%
Routing protocols are crucial to self-organize wireless sensor networks (WSNs), which have been widely studied in recent years. For some specific applications, both energy aware and reliable data transmission need to be considered together. Historical link status should be captured and taken into account in making data forwarding decisions to achieve the data reliability and energy efficiency tradeoff. In this paper, a dynamic window concept (m, k) is presented to record the link historical information and a link quality estimation based routing protocol (LQER) are proposed, which integrates the approach of minimum hop field and (m, k). The performance of LQER is evaluated by extensive simulation experiments to be more energy-aware, with lower loss rate and better scalability than MHFR [1] and MCR [2]. Thus the WSNs with LQER get longer lifetime of networks and better link quality.

Integration and Analysis of Neighbor Discovery and Link Quality Estimation in Wireless Sensor Networks

Radi, Marjan; Dezfouli, Behnam; Abu Bakar, Kamalrulnizam; Abd Razak, Shukor
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Publicado em 11/02/2014 EN
Relevância na Pesquisa
46.09%
Network connectivity and link quality information are the fundamental requirements of wireless sensor network protocols to perform their desired functionality. Most of the existing discovery protocols have only focused on the neighbor discovery problem, while a few number of them provide an integrated neighbor search and link estimation. As these protocols require a careful parameter adjustment before network deployment, they cannot provide scalable and accurate network initialization in large-scale dense wireless sensor networks with random topology. Furthermore, performance of these protocols has not entirely been evaluated yet. In this paper, we perform a comprehensive simulation study on the efficiency of employing adaptive protocols compared to the existing nonadaptive protocols for initializing sensor networks with random topology. In this regard, we propose adaptive network initialization protocols which integrate the initial neighbor discovery with link quality estimation process to initialize large-scale dense wireless sensor networks without requiring any parameter adjustment before network deployment. To the best of our knowledge, this work is the first attempt to provide a detailed simulation study on the performance of integrated neighbor discovery and link quality estimation protocols for initializing sensor networks. This study can help system designers to determine the most appropriate approach for different applications.

Blind Estimation of Perceptual Quality for Modern Speech Communications

Falk, Tiago
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 1412501 bytes; application/pdf
EN; EN
Relevância na Pesquisa
56.24%
Modern speech communication technologies expose users to perceptual quality degradations that were not experienced earlier with conventional telephone systems. Since perceived speech quality is a major contributor to the end user's perception of quality of service, speech quality estimation has become an important research field. In this dissertation, perceptual quality estimators are proposed for several emerging speech communication applications, in particular for i) wireless communications with noise suppression capabilities, ii) wireless-VoIP communications, iii) far-field hands-free speech communications, and iv) text-to-speech systems. First, a general-purpose speech quality estimator is proposed based on statistical models of normative speech behaviour and on innovative techniques to detect multiple signal distortions. The estimators do not depend on a clean reference signal hence are termed ``blind." Quality meters are then distributed along the network chain to allow for both quality degradations and quality enhancements to be handled. In order to improve estimation performance for wireless communications, statistical models of noise-suppressed speech are also incorporated. Next, a hybrid signal-and-link-parametric quality estimation paradigm is proposed for emerging wireless-VoIP communications. The algorithm uses VoIP connection parameters to estimate a base quality representative of the packet switching network. Signal-based distortions are then detected and quantified in order to adjust the base quality accordingly. The proposed hybrid methodology is shown to overcome the limitations of existing pure signal-based and pure link parametric algorithms. Temporal dynamics information is then investigated for quality diagnosis for hands-free speech communications. A spectro-temporal signal representation...

Reliable link quality estimation in low-power wireless networks and its impact on tree-routing

Baccour, Nouha; Koubâa, Anis; Youssef, Habib; Alves, Mário
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em /04/2015 ENG
Relevância na Pesquisa
66.11%
Radio link quality estimation is essential for protocols and mechanisms such as routing, mobility management and localization, particularly for low-power wireless networks such as wireless sensor networks. Commodity Link Quality Estimators (LQEs), e.g. PRR, RNP, ETX, four-bit and RSSI, can only provide a partial characterization of links as they ignore several link properties such as channel quality and stability. In this paper, we propose F-LQE (Fuzzy Link Quality Estimator, a holistic metric that estimates link quality on the basis of four link quality properties—packet delivery, asymmetry, stability, and channel quality—that are expressed and combined using Fuzzy Logic. We demonstrate through an extensive experimental analysis that F-LQE is more reliable than existing estimators (e.g., PRR, WMEWMA, ETX, RNP, and four-bit) as it provides a finer grain link classification. It is also more stable as it has lower coefficient of variation of link estimates. Importantly, we evaluate the impact of F-LQE on the performance of tree routing, specifically the CTP (Collection Tree Protocol). For this purpose, we adapted F-LQE to build a new routing metric for CTP, which we dubbed as F-LQE/RM. Extensive experimental results obtained with state-of-the-art widely used test-beds show that F-LQE/RM improves significantly CTP routing performance over four-bit (the default LQE of CTP) and ETX (another popular LQE). F-LQE/RM improves the end-to-end packet delivery by up to 16%...

Hierarchical Range Sectoring and Bidirectional Link Quality Estimation for On-demand Collections in WSNs

Valls, Víctor; Sánchez, José Luis; Cano, Cristina; Bellalta, Boris; Oliver, Miquel
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
45.94%
The paper presents two mechanisms for designing an on-demand, reliable and efficient collection protocol for Wireless Sensor Networks. The former is the Bidirectional Link Quality Estimation, which allows nodes to easily and quickly compute the quality of a link between a pair of nodes. The latter, Hierarchical Range Sectoring, organizes sensors in different sectors based on their location within the network. Based on this organization, nodes from each sector are coordinated to transmit in specific periods of time to reduce the hidden terminal problem. To evaluate these two mechanisms, a protocol called HBCP (Hierarchical-Based Collection Protocol), that implements both mechanisms, has been implemented in TinyOS 2.1, and evaluated in a testbed using TelosB motes. The results show that the HBCP protocol is able to achieve a very high reliability, especially in large networks and in scenarios with bottlenecks.; Comment: 22 pages, 11 figures

An Empirical Study on the Procedure to Derive Software Quality Estimation Models

Xu, Jie; Ho, Danny; Capretz, Luiz Fernando
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 24/07/2015
Relevância na Pesquisa
46.12%
Software quality assurance has been a heated topic for several decades. If factors that influence software quality can be identified, they may provide more insight for better software development management. More precise quality assurance can be achieved by employing resources according to accurate quality estimation at the early stages of a project. In this paper, a general procedure is proposed to derive software quality estimation models and various techniques are presented to accomplish the tasks in respective steps. Several statistical techniques together with machine learning method are utilized to verify the effectiveness of software metrics. Moreover, a neuro-fuzzy approach is adopted to improve the accuracy of the estimation model. This procedure is carried out based on data from the ISBSG repository to present its empirical value.

Building an OSS Quality Estimation Model with CATREG

Xu, Jie; Ho, Danny; Capretz, Luiz Fernando
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 24/07/2015
Relevância na Pesquisa
45.95%
Open Source Software (OSS) has been a popular form in software development. In this paper, we use statistical approaches to derive OSS quality estimation models. Our objective is to build estimation models for the number of defects with metrics at project levels. First CATREG (Categorical regression with optimal scaling) is used to obtain quantifications of the qualitative variables. Then the independent variables are validated using the stepwise linear regression. The process is repeated to acquire optimal quantifications and final regression formula. This modeling process is performed based on data from the OSS communities and is proved to be practically valuable.

Intelligent Hybrid Man-Machine Translation Quality Estimation

Sabek, Ibrahim; Yousri, Noha A.; Elmakky, Nagwa; Habib, Mona
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 07/07/2013
Relevância na Pesquisa
45.88%
Inferring evaluation scores based on human judgments is invaluable compared to using current evaluation metrics which are not suitable for real-time applications e.g. post-editing. However, these judgments are much more expensive to collect especially from expert translators, compared to evaluation based on indicators contrasting source and translation texts. This work introduces a novel approach for quality estimation by combining learnt confidence scores from a probabilistic inference model based on human judgments, with selective linguistic features-based scores, where the proposed inference model infers the credibility of given human ranks to solve the scarcity and inconsistency issues of human judgments. Experimental results, using challenging language-pairs, demonstrate improvement in correlation with human judgments over traditional evaluation metrics.; Comment: 8 pages, 3 figures, 5 tables

Practical Rate and Route Adaptation with Efficient Link Quality Estimation for IEEE 802.11b/g Multi-Hop Networks

Zhou, Jinglong; Rao, Vijay S.; Pawełczak, Przemysław; Wu, Daniel; Mohapatra, Prasant
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.15%
Accurate and fast packet delivery rate (PDR) estimation, used in evaluating wireless link quality, is a prerequisite to increase the performance of mobile, multi-hop and multi-rate wireless ad hoc networks. Unfortunately, contemporary PDR estimation methods, i.e. beacon-based packet counting in Estimated Transmission Time and Expected Transmission Count metrics, have unsatisfactory performance. Therefore, in this paper we propose a novel PDR estimation method based on SNR profiles. We classify all possible link quality estimation methods and compare them analytically against our design. Results show that it leads to a more efficient link quality estimation. Further investigations with the prototype implementation of our method in IEEE 802.11b/g testbeds reveal that the accuracy of PDR estimation in mobile scenarios can be improved up to 50% in comparison to generic packet-based PDR. Experiments with the same prototype on link and routing layers for different measurement scenarios show that it leads to a better rate adaptation and route selection in the form of end-to-end throughput increase compared to traditional packet counting methods.

Translation and Quality : Editorial

Görög, Attila
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Artigo de Revista Científica Formato: application/pdf; application/pdf
Publicado em //2014 ENG
Relevância na Pesquisa
45.88%
The world is producing more and more content and needs increasing volumes to be translated. The only way to offer large amounts of information and goods in multiple languages fast while staying within reasonable budgets is by making a compromise and provide content with different levels of quality using new translation channels and translation technology. This differentiation will, in turn, require new ways of evaluating the quality of translated content. This issue has been co-edited by Attila Görög (TAUS) and Pilar Sánchez-Gijón (Tradumàtica Research Group), and focuses on translation quality, that remains a concept of major importance both in the translation industry and in academia.; El món produeix cada cop més contingut i necessita que la quantitat de text que es tradueix també augmenti. L'única manera d’oferir grans quantitats d’informació i béns en diversos idiomes de manera ràpida i sense abandonar pressupostos raonables passa per assumir que es poden oferir continguts amb diferents nivells de qualitat recorrent a nous canals de traducció i a les tecnologies de la traducció. Aquest canvi, al seu torn, requereix de noves formes d’avaluar la qualitat del contingut traduït. Aquest número ha estat coeditat per Attila Görög (TAUS) i Pilar Sánchez-Gijón (Grup de Recerca Tradumàtica)...

COMPOSITIONAL KRIGING APPLIED TO THE RESERVE ESTIMATION OF A GRANITE DEPOSIT

SAAVEDRA,ÁNGELES; ORDÓÑEZ,CELESTINO; TABOADA,JAVIER; ARMESTO,JULIA
Fonte: DYNA Publicador: DYNA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2010 EN
Relevância na Pesquisa
45.99%
Making an accurate estimate of quality distribution in a granite deposit is essential, both from a financial point of view, to determine the profitability of the site, and from an environmental perspective, to focus operations on the most profitable areas thereby reducing the extent of land affected by such work. Granite is extracted in blocks whose profitability and value depend on the final size of the slabs, which is an important factor in defining quality. This article uses a variant of disjunctive kriging in order to determine the quality of granite in one of the largest reserves in the world-the Porriño deposit located in northwest Spain. This method, unlike classical disjunctive kriging, considers random variables that are not necessarily binary. The advantage of using this technique compared to the classical statistical cokriging technique is that all the qualities are considered as variables with the same importance and that the sum of quality percentages in a block is one hundred percent. The validity of the method was tested in a cross-validation process. The results compared favourably with those obtained using ordinary cokriging and fuzzy kriging.