509 research outputs found

    The complete contents of 'The Mediterranean Naturalist', a periodical published in Malta between 1891 and 1893

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    An account is given of the journal "The Mediterranean Naturalist', edited and published by John Henry Cooke (1862- 1933) towards the end of the nineteenth century. The complete contents of the twenty-seven issues in three volumes are listed, with an indication of those articles concerning Malta or with a Maltese connotation.peer-reviewe

    Emission line taxonomy and the nature of AGN-looking galaxies in the SDSS

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    Massive spectroscopic surveys like the SDSS have revolutionized the way we study AGN and their relations to the galaxies they live in. A first step in any such study is to define samples of different types of AGN on the basis of emission line ratios. This deceivingly simple step involves decisions on which classification scheme to use and data quality censorship. Galaxies with weak emission lines are often left aside or dealt with separately because one cannot fully classify them onto the standard Star-Forming, Seyfert of LINER categories. This contribution summarizes alternative classification schemes which include this very numerous population. We then study how star-formation histories and physical properties of the hosts vary from class to class, and present compelling evidence that the emission lines in the majority of LINER-like systems in the SDSS are not powered by black-hole accretion. The data are fully consistent with them being galaxies whose old stars provide all the ionizing power needed to explain their line ratios and luminosities. Such retired galaxies deserve a place in the emission line taxonomy.Comment: 8 pages, 4 figures, Proceedings of IAU Symposium 267, Co-Evolution of Central Black Holes and Galaxie

    A Robust Fringe-Adjusted Joint Transform Correlator for Efficient Object Detection

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    The fringe-adjusted joint transform correlation (FJTC) technique has been widely used for real-time optical pattern recognition applications. However, the classical FJTC technique suffers from target distortions due to noise, scale, rotation and illumination variations of the targets in input scenes. Several improvements of the FJTC have been proposed in the literature to accommodate these problems. Some popular techniques such as synthetic discriminant function (SDF) based FJTC was designed to alleviate the problems of scale and rotation variations of the target, whereas wavelet based FJTC has been found to yield better performance for noisy targets in the input scenes. While these techniques integrated with specific features to improve performance of the FJTC, a unified and synergistic approach to equip the FJTC with robust features is yet to be done. Thus, in this paper, a robust FJTC technique based on sequential filtering approach is proposed. The proposed method is developed in such a way that it is insensitive to rotation, scale, noise and illumination variations of the targets. Specifically, local phase (LP) features from monogenic signal is utilized to reduce the effect of background illumination thereby achieving illumination invariance. The SDF is implemented to achieve rotation and scale invariance, whereas the logarithmic fringe-adjusted filter (LFAF) is employed to reduce the noise effect. The proposed technique can be used as a real-time region-of-interest detector in wide-area surveillance for automatic object detection. The feasibility of the proposed technique has been tested on aerial imagery and has observed promising performance in detection accuracy

    Multiple Object Detection in Hyperspectral Imagery Using Spectral Fringe-Adjusted Joint Transform Correlator

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    Hyperspectral imaging (HSI) sensors provide plenty of spectral information to uniquely identify materials by their reflectance spectra, and this information has been effectively used for object detection and identification applications. Joint transform correlation (JTC) based object detection techniques in HSI have been proposed in the literatures, such as spectral fringe-adjusted joint transform correlation (SFJTC) and with its several improvements. However, to our knowledge, the SFJTC based techniques were designed to detect only similar patterns in hyperspectral data cube and not for dissimilar patterns. Thus, in this paper, a new deterministic object detection approach using SFJTC is proposed to perform multiple dissimilar target detection in hyperspectral imagery. In this technique, input spectral signatures from a given hyperspectral image data cube are correlated with the multiple reference signatures using the classassociative technique. To achieve better correlation output, the concept of SFJTC and the modified Fourier-plane image subtraction technique are incorporated in the multiple target detection processes. The output of this technique provides sharp and high correlation peaks for a match and negligible or no correlation peaks for a mismatch. Test results using real-life hyperspectral data cube show that the proposed algorithm can successfully detect multiple dissimilar patterns with high discrimination

    Multiclass Object Detection with Single Query in Hyperspectral Imagery Using Class-Associative Spectral Fringe-Adjusted Joint Transform Correlation

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    We present a deterministic object detection algorithm capable of detecting multiclass objects in hyperspectral imagery (HSI) without any training or preprocessing. The proposed method, which is named class-associative spectral fringe-adjusted joint transform correlation (CSFJTC), is based on joint transform correlation (JTC) between object and nonobject spectral signatures to search for a similar match, which only requires one query (training-free) from the object\u27s spectral signature. Our method utilizes class-associative filtering, modified Fourier plane image subtraction, and fringe-adjusted JTC techniques in spectral correlation domain to perform the object detection task. The output of CSFJTC yields a pair of sharp correlation peaks for a matched target and negligible or no correlation peaks for a mismatch. Experimental results, in terms of receiver operating characteristic (ROC) curves and area-under-ROC (AUROC), on three popular real-world hyperspectral data sets demonstrate the superiority of the proposed CSFJTC technique over other well-known hyperspectral object detection approaches

    How the three arches of the foot intercorrelate

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    Background: The foot is composed of medial, lateral and transverse arches which, particularly the medial arch, provide it with the ability to function both as a flexible and rigid structure for proper locomotion. Arches of the foot, as well as their effect on lower extremity function, have been studied. However, quantitative data on the relationship between these arches still remain scanty. The purpose of this study was, therefore, to examine how the three arches of the foot intercorrelate. Materials and methods: Seventy-six participants (58 males, 18 females) were recruited to participate in the study. Bilateral weight-bearing lateral radiographs of the right foot were taken from each participant. Navicular heights (NH), medial cuneiform height (MCH), calcaneal inclination angle (CIA) and calcaneal-first metatarsal angle (C1MA) were measured to represent the medial arch. The lateral arch was represented by cuboid height (CH) and calcaneal-fifth metatarsal angle (C5MA) whereas; MCH and CH represented the transverse arch. Mean difference of variables between males and females was compared using independent t-test while the correlation between the variables was determined using Pearson correlation. Results: All the variables were not significantly related to gender. Significant moderate to excellent linear correlations were observed between the variables. CIA showed the strongest correlation with C1MA (r = –0.90) and C5MA (r = –0.84) whereas, CH had the least correlation with other variables. Conclusions: The moderate to excellent correlations between the variables indicate that deformation or elevation of the medial arch may consequently result in similar movements of the lateral and transverse arches and vice versa

    Fertility differentials by ecological zones in rural West Java Province

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    This thesis examines fertility and family planning in the four ecological zones in Rural West Java Province: the Northern, Highland, Southern and Banten zones. It investigates variations in fertility among ever married women according to education, occupation, age at marriage, marital status and number of marriages. The index of fertility in this 3tudy is the mean number of children ever born to ever married women. The analysis found that both before and after standardization, there was an apparent dichotomy of fertility: the Highland and Banten zones with high fertility and the Southern and Northern zones with lower fertility. This dichotomy of fertility also persists when various socio-economic variables are controlled. This study also shows that the Highlanders and the Southerners accepted family planning more readily than the Northerners and Bantenese

    Cografts of Adrenal Medulla With Pretransected Peripheral Nerve

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