Three-dimensional object shape is commonly represented in terms of deformations of a triangular mesh from an exemplar shape. Existing models, however, are based on a Euclidean representation of shape deformations. In contrast, we argue that shape has a manifold structure: For example, summing the shape deformations for two people does not necessarily yield a deformation corresponding to a valid...

We present a novel method for automatic shape model building from a collection of training shapes. The result is a shape model consisting of the mean model and the major modes of variation with a dense correspondence map between individual shapes. The framework consists of iterations where a medial shape representation is deformed into the training shapes followed by computation of the shape me...

Natural variation in organ morphologies can have adaptive significance and contribute to speciation. However, the underlying allelic differences responsible for variation in organ size and shape remain poorly understood. We have utilized natural phenotypic variation in three Arabidopsis thaliana ecotypes to examine the genetic basis for quantitative variation in petal length, width, area, and s...

background: rna plays key role in many aspects of biological processes and its tertiary structure is critical for its biological function. rna secondary structure represents various significant portions of rna tertiary structure. since the biological function of rna is concluded indirectly from its primary structure, it would be important to analyze the relations between the rna sequences and t...

Three-dimensional object shape is commonly represented in terms of deformations of a triangular mesh from an exemplar shape. Existing models, however, are based on a Euclidean representation of shape deformations. In contrast, we argue that shape has a manifold structure: For example, summing the shape deformations for two people does not necessarily yield a deformation corresponding to a valid...

We assessed the variation in proximal femoral canal shape and its association with geometric and demographic parameters in primary hip OA. In a retrospective cohort study, the joint geometry of the proximal femur was evaluated on radiographs and corresponding CT scans of 345 consecutive patients with end-stage hip OA. Active shape modeling (ASM) was performed to assess the variation in endostea...

Previously recognized color and pattern variants of adult Cichla temensis in Amazon flood pulse river environments reflect the cycling of individuals through seasonal sexual maturity and spawning. Individuals also vary in shape from blocky to fusiform. To determine if shape differences are related to patterns of fat reserve deposition and utilization, and to quantify the relationship of shape w...

A new deformable shape model is defined with the following properties: (1) A-priori knowledge describes shapes not only by statistical variation of a fixed structure like active shape/appearance model but also by variability of structure using a production system. (2) Multi-resolution description of shape structures enable more constrained statistical variation of shape as the model evolves in ...

Variation in floral shape is of major interest to evolutionary and pollination biologists, plant systematists and developmental geneticists. Quantifying this variation has been difficult due to the three-dimensional (3D) complexity of angiosperm flowers. By combining 3D geometric representations of flowers obtained by micro-computed tomography scanning with geometric morphometric methods, well ...

An efficient method for scattering Genetic Algorithm (GA) individuals in the design space is proposed to accelerate airfoil shape optimization. The method used here is based on the variation of the mutation rate for each gene of the chromosomes by taking feedback from the current population. An adaptive method for airfoil shape parameterization is also applied and its impact on the optimum desi...