Net blotch, caused by the phytopathogen Drechslera teres, is a common disease of barley (Hordeum vulgare L) and is responsible for large economic losses in some barley growing areas. In this study the morphology and genetic variability of eight D. teres isolates from different regions of the Brazilian state of Rio Grande do Sul were investigated. Colony morphology was studied on potato-dextrose...

We examine the effect of listening level, i.e. the absolute sound pressure level at which sounds are reproduced, on music similarity, and in particular, on playlist generation. Current methods commonly use similarity metrics based on Mel-frequency cepstral coefficients (MFCCs), which are derived from the objective frequency spectrum of a sound. We follow this approach, but use the level-depende...

In this paper, a simple technique is proposed for face recognition among many human faces. It is based on the polynomial coefficients, covariance matrix and algorithm on common eigenvalues. The main advantage of the proposed approach is that the identification of similarity between human faces is carried out without computing actual eigenvalues and eigenvectors. A symmetric matrix is calculated...

Image coding using Discrete Wavelet Transform can attain very good results compared to traditional methods. In fact, most of the best known results for image coding have been related to DWT. A simple scheme to code the DWT coefficients is the Embedded zero-tree wavelet algorithm[1] by Shapiro. Embedded zero-tree wavelet can exploit both the similarity among subbands and the sparseness of the su...

Structural image features are exploited to construct perceptual image hashes in this work. The image is first preprocessed and divided into overlapped blocks. Correlation between each image block and a reference pattern is calculated. The intermediate hash is obtained from the correlation coefficients. These coefficients are finally mapped to the interval [0, 100], and scrambled to generate the...

DNA heterogeneity among members of the genus Brucella was demonstrated with the arbitrarily primed polymerase chain reaction (AP-PCR). Simple, reproducible genomic fingerprints from DNA of 25 different Brucella strains were generated with five arbitrarily chosen primers, alone and in pairs, with the PCR. Reaction conditions were optimized for each primer. Several DNA segments were amplified in ...

The production of informative random amplified polymorphic DNA (RAPD) markers using PCR and a single primer is often accompanied by the generation of artifactual (noninformative) bands as well. When RAPD data are used to compute genetic similarity coefficients, these artifacts (false positives, false negatives, or both) can cause large biases in the numerical values of the coefficients. As a re...

The objective of this study was to evaluate whether different similarity coefficients used with dominant markers can influence the results of cluster analysis, using eighteen inbred lines of maize from two different populations, BR-105 and BR-106. These were analyzed by AFLP and RAPD markers and eight similarity coefficients were calculated: Jaccard, Sorensen-Dice, Anderberg, Ochiai, Simple-mat...

The structural similarity (SSIM) index has been shown to be an useful tool in a wide variety of applications that involve the assessment of image quality and similarity. However, in-depth studies are still lacking on how to incorporate it for signal representation and approximation problems, where minimal mean squared error is still the dominant optimization criterion. Here we examine the probl...

Computation of semantic similarity between concepts is an important foundation for many research works. This paper focuses on IC (information content) computing methods and IC measures, which estimate the semantic similarities between concepts by exploiting the topological parameters of the taxonomy. Based on analyzing representative IC computing methods and typical semantic similarity measures...