140 research outputs found

    Marigold Blooming Maturity Levels Classification Using Machine Learning Algorithms

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    Image processing is swiftly progressive in the area of computer science and engineering. Image classification is a fascinating task in image processing. In this study, we have classified the marigold blooming maturity levels like a marigold bud, partial blooming marigold, and fully blooming marigold. To classify the marigold blooming maturity levels are a tough and time-consuming task for human beings. Hence, an automatic marigold maturity levels classification tool is very adjuvant even for experience humans to classify the huge number of marigolds. For the sake of that, we have deliberated a novel system to classify automatically marigold blooming maturity levels image data by using machine learning algorithms. There are three types of machine learning models namely Artificial Neural Network(ANN), Convolutional Neural Network(CNN), and Support Vector Machine(SVM) that are used to automatically classify marigold maturity levels. Hence, we have preprocessed the image at first. Then we extract the various features from the marigold images. After that, these features have fed into Machine Learning(ML) models and classify these images into the category. From the experiment, we observed that the Convolutional Neural Network (CNN) model provides a high accuracy compared to other Artificial Neural Network(ANN) and Support Vector Machine(SVM) algorithms. The Convolutional Neural Network(CNN) models performed the best among all two classifiers with an overall accuracy of 93.9%. Our proposed system is efficiently classifying marigold maturity levels

    Systematics and biogeography of the arctic and boreal species of Primula

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    Thesis (Ph.D.) University of Alaska Fairbanks, 1987Four sections of the genus Primula are represented in northern North America: Aleuritia, Armerina, Crystallophlomis, and Cuneifolia. In this dissertation I discuss anatomical, morphological, cytological, ecological, and reproductive characters for thirteen species, and demonstrate coherence of sectional groups through cluster analysis and ordination. In Primula, distyly and homostyly play critical roles in systematics and biogeography. It is generally assumed that distylous individuals are almost completely outcrossed, and homostyles are capable of selfing. In the taxa examined here, distyly exists at the diploid and tetraploid levels while homostyly is seen in both diploids and higher polyploids. I suggest that distyly breaks down with selection for reproductive assurance in environments where pollinators are unreliable, or following hybridization in conjunction with polyploidy. While most northern Primula species are homostylous, several examples of distylous taxa demonstrate that this can be a successful breeding system in higher latitudes. In homostyles, self-compatibility and the proximity of reproductive organs assures a high degree of selfing; however, most northern homostylous taxa also exhibit attributes which suggest facultative outcrossing is common. In North America, evolution in Primula has been strongly influenced by Quaternary events leading to isolation, migration, and secondary contact of gene pools, in association with the breakdown of distyly to homostyly. The success of homostylous taxa is at least partially due to their ability to self-fertilize coupled with the availability of areas to colonize when Pleistocene ice retreated. The phytogeographic affinities, cytology, and reproductive shifts of Primula make it a useful model for processes occurring in the Alaskan flora. The steppes and mountains of Asia have been important source areas, and migration has taken place along mountains, rivers, island arcs, and coastlines. Speciation in the genus has been aided by hybridization, polyploidy, and reproductive diversity

    The impact of spatio-temporal changes in flora attributes and pollen availability on insect visitors in Lamiaceae species

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    There is growing evidence that food, in particular pollen, limitation is the strongest factor in pollinator decline. We have considered the potential effects of diversity in plant-community attributes as well as variations in the pollen and energy amount on the abundance and frequency of insect visitors to the Lamiaceae species Salvia pratensis L., S. verticillata L., Thymus serpyllum L., Betonica officinalis L. syn. Stachys officinalis (L.) Trevis., and Origanum vulgare L. The species were grown in two different habitat types (dry grassland vs. railway embankment) in the Lublin Upland, Poland. We found significant inter-species, inter-habitat, and inter-year disparities in the pollen mass and total energy amount per unit area. Canonical correspondence analysis (CCA) revealed that the blossom cover, species richness, and diversity noted at the plant community level significantly influenced the distribution of insect visitors to Lamiaceae species. The pollen caloric value and pollen abundance (but not the protein content in the pollen) had a considerable impact on the abundance and frequency of honeybees, bumblebees, and solitary bees in Lamiaceae flowers. Butterflies, beetles and flies did not respond to these factors. The model including all variables explained 66.4% of the observed variance. The studied Lamiaceae species, due to abundant flowering and good pollen nutritional value should be considered in the protocols to improve food resources, especially for social bees; however, disparities in pollen quantity and energy amount should not be ignored

    MGRO Recognition Algorithm-Based Artificial Potential Field for Mobile Robot Navigation

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    This paper describes a novel recognition algorithm which includes mean filter, Gaussian filter, Retinex enhancement method, and Ostu threshold segmentation method (MGRO) for the navigation of mobile robots with visual sensors. The approach includes obstacle visual recognition and navigation path planning. In the first part, a three-stage method for obstacle visual recognition is constructed. Stage 1 combines mean filtering and Gaussian filtering to remove random noise and Gauss noise in the environmental image. Stage 2 increases image contrast by using the Retinex enhancement method. Stage 3 uses the Ostu threshold segmentation method to achieve obstacle feature extraction. A navigation method based on the auxiliary visual information is constructed in the second part. The method is based on the artificial potential field (APF) method and is able to avoid falling into local minimum by changing the repulsion field function. Experimental results confirm that obstacle features can be extracted accurately and the mobile robot can avoid obstacles safely and arrive at target positions correctly

    Meaningful Matches in Stereovision

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    This paper introduces a statistical method to decide whether two blocks in a pair of of images match reliably. The method ensures that the selected block matches are unlikely to have occurred "just by chance." The new approach is based on the definition of a simple but faithful statistical "background model" for image blocks learned from the image itself. A theorem guarantees that under this model not more than a fixed number of wrong matches occurs (on average) for the whole image. This fixed number (the number of false alarms) is the only method parameter. Furthermore, the number of false alarms associated with each match measures its reliability. This "a contrario" block-matching method, however, cannot rule out false matches due to the presence of periodic objects in the images. But it is successfully complemented by a parameterless "self-similarity threshold." Experimental evidence shows that the proposed method also detects occlusions and incoherent motions due to vehicles and pedestrians in non simultaneous stereo.Comment: IEEE Transactions on Pattern Analysis and Machine Intelligence 99, Preprints (2011) 1-1

    The evolutionary ecology of floral scent in Hesperis matronalis: assessing the potential for pollinator-mediated natural selection.

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    Heritable trait variation and differential fitness among trait variants are conditions required for pollinator-mediated natural selection on attractive traits like floral scent. However, previous studies of floral scent have focused on assessing evolution through stereotypical pollination syndromes and often fail to evaluate the conditions of natural selection. I assess the potential for pollinator-mediated natural selection on the floral scent of color polymorphic Hesperis matronalis (Brassicaceae). A study that assessed the importance of shared biochemistry between floral scent and color found significant diurnal variation in scent emission and a population-specific effect of floral color on floral scent composition. Specifically, purple morphs tended to be similar, while white morphs tended to differ significantly. A survey of five wild populations across part of H. matronalis's introduced range supported this trend, particularly for aromatic composition; both scent composition and overall emission rates varied among populations. An experiment comparing scent profiles of plants grown in a common garden environment suggested both environmental and genetic causes of among-population variation. A three-part study assessed the relationship between scent and fitness. Experimental augmentation of floral targets with color-specific floral scent revealed increased syrphid fly visitation in response to increased scent emission rate, predicting a positive linear relationship between plant fitness and emission rate. An experiment limiting pollinator access to plants showed this expected relationship for plants exposed to diurnal pollinators, but no relationship for plants exposed to night pollinators. In contrast, I found a negative quadratic relationship between daytime emission rate and fitness across plants in four large wild populations, suggesting possible costs of scent production under wild conditions, i.e., attraction of herbivores or energetic expenditures.Overall, this dissertation suggests strong potential for pollinator-mediated natural selection on H. matronalis floral scent. Additionally, the results illustrate the importance of assessing all conditions necessary for natural selection of floral scent rather than relying on the observational pollination syndrome framework to describe the evolutionary trajectory of a species

    Fallow lands as a tool for farmland biodiversity conservation

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    Agri-environmental schemes (AES) have been designed to counteract the dramatic decline in farmland biodiversity across Europe driven by agricultural intensification. This study aimed to shed light on these aspects for the specific case of fallow fields located in a semi-arid region of the north-eastern Iberian Peninsula. Knowledge of the vegetation assembly response (in terms of functionality) to the different agricultural management and landscape conditions improves understanding of their effect on higher trophic levels, and may potentially contribute to enhancing their viability. In this study, different management practices were experimentally tested to show their effects on the habitat suitability of two groups of species which represent farmland biodiversity and ecosystem services: steppe bird species insect pollinators, respectively. Moreover, the surrender habitat assemblage was also taken into account. This study aims to improve current conservation measures by providing valuable information about the different aptitudes of management strategies, according to the preferences of the target species studied.El diseño de las medidas agroambientales tiene como principal objetivo frenar la importante pérdida de biodiversidad asociada a la intensificación agrícola que ha tenido lugar en Europa. Este estudio tiene como objetivo contribuir a incrementar dicho conocimiento para el caso específico de los barbechos en las zonas semi-áridas del noreste de la Península Ibérica. Conocer las respuestas de la comunidad vegetal –en cuanto a variaciones en sus características funcionales- a diferentes manejos agrícolas y condiciones del paisaje permite una mejor comprensión de sus efectos sobre niveles tróficos superiores, pudiendo contribuir a mejorar su viabilidad. En el presente estudio fueron evaluadas de forma experimental diferentes prácticas agrícolas con el objetivo de determinar la idoneidad del hábitat de dos grupos de especies representantes de la biodiversidad en zonas agrícolas –aves esteparias- y servicios ecosistémicos –polinizadores-. Además la configuración paisajística de los alrededores también fue tenida en cuenta. Este estudio proporciona información valiosa sobre la adecuación de los diferentes manejos agrícolas en barbechos de acuerdo a las preferencias de las especies de interés para la conservación y así contribuir en la mejora y efectividad de las medidas aplicadas en la actualidad.El disseny de mesures agroambientals en espais agrícoles té com a principal objectiu frenar l'important pèrdua de biodiversitat associada a la intensificació de l'agricultura que ha tingut lloc a Europa en els darrers decennis. El treball que aquí es presenta té com a objectiu aportar nou coneixement en aquest àmbit, en concret sobre la gestió dels guarets en les zones semi-àrides del nord-est de la Península Ibèrica. Així, el coneixement de la resposta de la comunitat vegetal -pel que fa a variacions en les seves característiques funcionals- a diferents manejos agrícoles i a condicions del paisatge, ha de permetre una millor comprensió dels seus efectes sobre nivells tròfics superiors i contribuir a millorar la seva viabilitat. En aquest sentit, en el present estudi han estat avaluades, de forma experimental, diferents pràctiques agrícoles amb l'objectiu de determinar la idoneïtat de l'hàbitat per a dos grups d'organismes: d’una banda les aus estepàries, com a representants de la biodiversitat en aquestes zones agrícoles, i d’una altra, els pol•linitzadors, indicadors de l’eficiència dels serveis ecosistèmics. En aquest context, la configuració paisatgística de l’entorn ha estat també tinguda en compte. Aquest estudi proporciona informació acurada sobre l'adequació dels diferents manejos agrícoles als requisits i preferències de les espècies d'interès per a la seva conservació en aquests espais, i alhora aporta propostes de millora per assolir una major efectivitat de les mesures agroambientals fins ara implementades

    Biosystematics of Phlox kelseyi (Polemoniaceae)

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