Multiple structure recovery with T-linkage

reserved2noThis work addresses the problem of robust fitting of geometric structures to noisy data corrupted by outliers. An extension of J-linkage (called T-linkage) is presented and elaborated. T-linkage improves the preference analysis implemented by J-linkage in term of performances and robustness, considering both the representation and the segmentation steps. A strategy to reject outliers and to estimate the inlier threshold is proposed, resulting in a versatile tool, suitable for multi-model fitting “in the wild”. Experiments demonstrate that our methods perform better than J-linkage on simulated data, and compare favorably with state-of-the-art methods on public domain real datasets.mixedMagri L.; Fusiello A.Magri, L.; Fusiello, A

Before and Beyond the Bachelor Machine

This paper will examine the importance of Marcel Duchamp’s La Machine Célibataire (The Bachelor) on Art and Technology in the 20th and 21st centurie

MSClique: Multiple structure discovery through the maximum weighted clique problem

We present a novel approach for feature correspondence and multiple structure discovery in computer vision. In contrast to existing methods, we exploit the fact that point-sets on the same structure usually lie close to each other, thus forming clusters in the image. Given a pair of input images, we initially extract points of interest and extract hierarchical representations by agglomerative clustering. We use the maximum weighted clique problem to find the set of corresponding clusters with maximum number of inliers representing the multiple structures at the correct scales. Our method is parameter-free and only needs two sets of points along with their tentative correspondences, thus being extremely easy to use. We demonstrate the effectiveness of our method in multiple-structure fitting experiments in both publicly available and in-house datasets. As shown in the experiments, our approach finds a higher number of structures containing fewer outliers compared to state-of-the-art methods.Peer ReviewedPostprint (published version

Sistemática e evolução do gênero de morcegos neotropical Lophostoma d'Orbigny, 1836 (Chiroptera: Phyllostomidae)

Morcegos Lophostoma d'Orbigny, 1836 (Chiroptera: Phyllostomidae) estão distribuídos desde o sul do México até o sudoeste do Paraguai e sudeste do Brasil. Este gênero inclui sete espécies de morcegos insetívoros, conhecidos como morcegos-de-orelhas-redondas. A sistemática e taxonomia do grupo têm sido objeto de diversos estudos, que utilizando dados morfológicos e moleculares revelaram uma enorme diversidade fenotípica e genotípica, indicando a possível existência de espécies crípticas, principalmente em Lophostoma brasiliense Peters, 1866 e Lophostoma silvicola d'Orbigny, 1836. O principal objetivo do presente estudo foi analisar a diversidade críptica de Lophostoma ao longo de sua distribuição geográfica, integrando análises moleculares, morfológicas e morfométricas para esclarecer os limites taxonômicos, distribuição e relações evolutivas das suas espécies. No primeiro capítulo, apresento uma avaliação taxonômica de L. brasiliense. Foram utilizados métodos de delimitação fenotípica e molecular das espécies com base no marcador mitocondrial Citocromo c oxidase subunidade 1 (COI), dados morfológicos, morfométricos lineares e geométricos. Os resultados reconheceram L. brasiliense como duas linhagens distintas com distribuições alopátricas. Uma corresponde à L. brasiliense sensu stricto, com distribuição cis-andina; outra corresponde à L. nicaraguae (Goodwin, 1942), atualmente sinônimo de L. brasiliense, com distribuição transandina. O status de espécie válida é proposto para L. nicaraguae considerando as evidências apresentadas. No segundo capítulo, faço uma avaliação taxonômica de L. silvicola baseada em dois genes mitocondriais (COI, Cyt-b) e múltiplas evidências fenotípicas (morfologia qualitativa e quantitativa). As análises suportam a validação de duas entidades taxonômicas adicionais à L. silvicola: L. laephotis (Thomas, 1910) e L. amblyotis Peters, 1867. Por fim, apresento informações sobre a distribuição de cada uma das espécies aqui reconhecidas, bem como hipóteses sobre a sua diversificação, e discuto as possíveis implicações das barreiras geográficas na origem destas espécies.Bats of genus Lophostoma d'Orbigny, 1836 (Chiroptera: Phyllostomidae) are distributed from southern Mexico to southwestern Paraguay and southwestern Brazil. This genus includes seven species of insectivorous bats, which are known as round-eared bats. Systematics and taxonomy of the group have been the subject of several studies, which using morphological and molecular data revealed an enormous phenotypic and genetic diversity, indicating the possible existence of cryptic species, mainly in Lophostoma brasiliense Peters, 1866 and Lophostoma silvicola d'Orbigny, 1836. The main objective of the present study was to analyze the cryptic diversity of Lophostoma throughout its geographic distribution, integrating molecular, morphological and morphometric analyzes to clarify the taxonomic limits, distribution and evolutionary relationships of its species. In the first chapter, I present a taxonomic assessment of L. brasiliense. Phenotypic and molecular species delimitation methods were used based on the mitochondrial marker Cytochrome c oxidase subunit I (COI), morphological, linear and geometric morphometric data. The results recognized L. brasiliense as two distinct lineages with allopatric distributions. One corresponds to L. brasiliense sensu stricto, with a cis-Andean distribution; another corresponds to L. nicaraguae (Goodwin, 1942), currently synonymous with L. brasiliense, with trans-Andean distribution. Valid species status is proposed for L. nicaraguae considering the evidence presented. In the second chapter, I perform a taxonomic assessment of L. silvicola based on two mitochondrial genes (COI, Cyt-b) and multiple phenotypic evidences (qualitative and quantitative morphology). The analyzes supported the validation of two additional taxonomic entities to L. silvicola: L. laephotis (Thomas, 1910) and L. amblyotis Peters, 1867. Finally, I present information on the distribution of each of the species recognized here, as well as hypotheses about their diversification, and discuss the possible implications of geographic barriers in the origin of these species

State-of-the-art in aerodynamic shape optimisation methods

Aerodynamic optimisation has become an indispensable component for any aerodynamic design over the past 60 years, with applications to aircraft, cars, trains, bridges, wind turbines, internal pipe flows, and cavities, among others, and is thus relevant in many facets of technology. With advancements in computational power, automated design optimisation procedures have become more competent, however, there is an ambiguity and bias throughout the literature with regards to relative performance of optimisation architectures and employed algorithms. This paper provides a well-balanced critical review of the dominant optimisation approaches that have been integrated with aerodynamic theory for the purpose of shape optimisation. A total of 229 papers, published in more than 120 journals and conference proceedings, have been classified into 6 different optimisation algorithm approaches. The material cited includes some of the most well-established authors and publications in the field of aerodynamic optimisation. This paper aims to eliminate bias toward certain algorithms by analysing the limitations, drawbacks, and the benefits of the most utilised optimisation approaches. This review provides comprehensive but straightforward insight for non-specialists and reference detailing the current state for specialist practitioners

Diversity and Diversification Across the Global Radiation of Extant Bats

Diversity is not distributed equally across the tree of life. This fundamental observation is central to ecology and evolutionary biology, and spans both spatial and temporal scales. Species richness, for example, is unevenly distributed both within and across clades. Biodiversity is often spatially concentrated in the tropics, with lower richness in temperate biomes. Some clades are characterized by extremely high ecological and morphological diversity, while others remain static across geologic timescales. This dissertation highlights these patterns of diversity across extant bats, the Order Chiroptera, and seeks to understand the evolutionary processes of diversification that govern them. Chapter 1 serves as both an introduction to the major questions of the dissertation and an overview of extant bat diversity, and how it varies spatially, phylogenetically, and ecologically across the globe. In this chapter, I primarily focus on spatial variation in regional richness patterns, and on the major differences between temperate and tropical bat diversity. In Chapter 2, I assemble a species-level molecular phylogeny of the order that is time-calibrated with fossil data. Using this phylogeny, I infer speciation dynamics across the order, and find that despite the imbalances in species richness, speciation rates are relatively homogeneous. I only infer strong evidence for more rapid rates within the subfamily Stenodermatinae, a clade of Neotropical phyllostomid bats. In Chapter 3, I develop models to test whether bat species co-occurrence is constrained by relatedness or ecomorphological similarity. Contrary to theoretical predictions and results from other major clades, I find that neither of these metrics of divergence controls co-occurrence in sympatry across most bats and realms. The only exception is the Neotropical realm, where bat species are most likely to co-occur when they are the most ecomorphologically similar to one another. This potentially indicates that Neotropical bat communities and species pools, at broad regional scales, are sorted by filtering processes that cluster bats with similar ecologies together in space. For Chapters 4 and 5, I assess how ecology and morphology are linked in New World bats. Chapter 4 describes an open-access, X-ray computed microtomography database of bat skulls, and how this resource can be used by the broader scientific and educational community. Chapter 5 combines crania from that database with diet data across New World bats, and tests whether ecological and morphological evolution are correlated in this group. Surprisingly, I find that patterns of ecological, trophic evolution are largely decoupled from morphological evolution. There is considerable heterogeneity in how readily different clades transition among trophic guilds, yet cranial shape evolution is surprisingly homogeneous. This decoupled pattern is potentially driven by underestimated trophic plasticity and omnivory among noctilionoid bats, as well as high lability among bat crania. Finally, in Chapter 6, I conclude with a summary of our major findings, and some thoughts on ecological and macroevolutionary inference both within bats and across the tree of life.PHDEcology and Evolutionary BiologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/145993/1/jeffjshi_1.pd