scholarly journals Automatic generation of objective footprint outlines

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7203 ◽  
Author(s):  
Jens N. Lallensack
Keyword(s):  
Shape Analysis ◽  
A Priori ◽  
Three Dimensional ◽  
Automatic Generation ◽  
Contour Lines ◽  
Statistical Shape ◽  
Angular Measurements ◽  
Three Dimensional Models ◽  
Objective Basis ◽  
Definition Of

The objective definition of footprint margins poses a central problem in ichnology. The transition from the footprint to the surrounding sediment is often continuous, and the footprint wall complex, requiring interpolation, approximation, and a priori assumptions about trackmaker anatomy to arrive at feasible interpretations of footprint shapes. The degree of subjectivity of such interpretations is substantial, and outlines produced by separate researchers can differ greatly. As a consequence, statistical shape analysis, regardless if based on linear and angular measurements or on the shape as a whole, are neither fully repeatable nor objective. Here I present an algorithm implemented in the programming environment R that is able to generate continuous footprint outlines based on three-dimensional models—fully automatically, objectively, and repeatable. The approach, which is based on contour lines extracted from the model, traces the outline at the point where the slope of the track wall is steepest. An option for automatic landmark placement is implemented for tridactyl footprints. A case study was carried out on 13 footprints of a single trackway of a theropod trackmaker from the Lower Cretaceous of Münchehagen, Germany. Analysis of the landmark coordinates returned by the script did reproduce statistical results published in an earlier study that was based on human-made interpretative drawings, demonstrating the applicability of the present method for the objective and quantitative shape analysis of tracks. Although faint anatomical details are not always recorded and features not related to the foot anatomy may be included, the generated outlines tend to correspond with human-made interpretative drawings regarding the overall shape. While not suited as a full replacement of interpretative drawings, these generated outlines may be used as an objective basis for such interpretations.

Automatic tourist attraction and representative icon determination for tourist map generation

2013 ◽  
Vol 13 (1) ◽  
pp. 18-28 ◽  
Author(s):  
Chao-Hung Lin ◽  
Jyun-Yuan Chen ◽  
Shun-Siang Hsu ◽  
Yun-Huan Chung
Keyword(s):  
User Study ◽  
Three Dimensional ◽  
Automatic Generation ◽  
Visual Features ◽  
Tourist Attraction ◽  
Tourist Attractions ◽  
Photo Sharing ◽  
Map Generation ◽  
Three Dimensional Models ◽  
Better Than

Tourist maps are designed to direct tourists to tourist attractions in unfamiliar areas. A well-designed tourist map can provide tourists with sufficient and intuitive information about places of interest. Thus, providing up-to-date information on places of interest and selecting their representative icons are fundamental and important in automatic generation of tourist maps. In this article, approaches for determining places of interest and for determining their representative icons are introduced. In contrast to general digital tourist maps that use text, simple shapes, or three-dimensional models, we use photos that offer abundant visual features of places of interest as icons in tourist maps. The photos are automatically extracted from a repository of photos downloaded from photo-sharing communities. Tourist attractions and their corresponding image icons are determined by means of photo voting and photo quality assessment. Qualitative analyses, including a user study and experiments in several areas with numerous tourist attractions, indicated that the proposed method can generate visually pleasant and elaborate tourist maps. In addition, the analyses indicated that the map produced by our method is better than maps generated by related methods and is comparable to hand-designed tourist maps.

scholarly journals METHODS FOR MODELS PARAMETERS ESTIMATE TO SOLVE PROBLEMS ON 3D RECONSTRUCTION OF REAL OBJECTS COMPLEX MODELS

2016 ◽  
Vol 2016 (3) ◽  
pp. 233-242 ◽  
Author(s):  
Владислав Колякин ◽  
Vladislav Kolyakin ◽  
Владимир Аверченков ◽  
Vladimir Averchenkov ◽  
Максим Терехов ◽  
...  
Keyword(s):  
Computer Games ◽  
Three Dimensional ◽  
3D Models ◽  
Model Parameters ◽  
Complex Objects ◽  
Image Brightness ◽  
Real Objects ◽  
Complex Models ◽  
Three Dimensional Models ◽  
Definition Of

Virtual threedimensional (3 D) models of complex objects are used in many fields of science and engineering, such as architecture, industry, medicine, robotics. Besides, 3D models are used in geoinformation systems, computer games, virtual and supplemented reality and so on. Three dimensional models can be formed in dif-ferent ways, one of which consists in 3 D reconstruc-tion. One of the stages of the 3 D reconstruction of complex models of real objects is a definition of the mathematical models of geometric primitives emphasized on the image. One of the ways for the estimate of model parameters is a method of Hough vote and its modifications – Hough probabilistic transformation, Hough random transformation, Hough hierarchical transformation, phase space blurriness, use of a gra-dient of image brightness and so on. As an alternative way for models selection is a choice of suitable points from a set of data.

scholarly journals Correlation between the cross-sectional morphology of the mandible and the three-dimensional facial skeletal pattern: A structural equation modeling approach

2018 ◽  
Vol 89 (1) ◽  
pp. 78-86 ◽  
Author(s):  
Mi So Ahn ◽  
Sang Min Shin ◽  
Te-Ju Wu ◽  
Dong Joon Lee ◽  
Ching-Chang Ko ◽  
...  
Keyword(s):  
Factor Analysis ◽  
Shape Analysis ◽  
Structural Equation ◽  
Three Dimensional ◽  
Equation Modeling ◽  
Outer Cortex ◽  
Cross Sectional ◽  
Statistical Shape ◽  
Skeletal Pattern ◽  
The Cross

ABSTRACT Objective: To clarify the relationship between the cross-sectional morphology of the mandible and vertical, transverse, and anteroposterior facial skeletal patterns using statistical shape analysis and structural equation modeling (SEM). Materials and Methods: We used 150 cone beam computed tomography (CBCT) images to obtain three-dimensional (3D) facial landmarks and cross-sectional images of the mandible. The morphology of the inner and outer cortices of the mandible was analyzed using statistical shape analysis, including generalized Procrustes analysis and principal component analysis (PCA). Factor analysis was performed to determine factors pertaining to the skeletal measurements and shape variations for the inner and outer cortices, following which a structural equation model was constructed. Results: Using factor analysis, characteristics of the vertical, transverse, and anteroposterior facial skeletal patterns were determined. PCA of the cross-sectional morphology of the mandible revealed 70% of the cumulative proportion by PC1 and PC2 after generalized Procrustes superimpositions. SEM showed complex relationships between the facial skeletal patterns and variations in the cross-sectional morphology of the mandibular cortices. The influence of the transverse factors on the outer cortex as a latent variable was relatively significant (P = .057). However, the influence of the vertical factors on the outer and inner cortices was not significant. Conclusions: The transverse skeletal pattern is associated with the morphology of the outer cortex of the mandible.

scholarly journals THE VARIATIONAL THEORY OF COMPLEX RAYS FOR THREE-DIMENSIONAL HELMHOLTZ PROBLEMS

2012 ◽  
Vol 20 (04) ◽  
pp. 1250021 ◽  
Author(s):  
LOUIS KOVALEVSKY ◽  
PIERRE LADEVÈZE ◽  
HERVÉ RIOU ◽  
MARC BONNET
Keyword(s):  
Spherical Harmonics ◽  
A Priori ◽  
Three Dimensional ◽  
Variational Theory ◽  
Actual Case ◽  
Analytical Properties ◽  
And Performance ◽  
Definition Of ◽  
Complex Rays

This paper proposes an extension of the variational theory of complex rays (VTCR) to three-dimensional linear acoustics, The VTCR is a Trefftz-type approach designed for mid-frequency range problems and has been previously investigated for structural dynamics and 2D acoustics. The proposed 3D formulation is based on a discretization of the amplitude portrait using spherical harmonics expansions. This choice of discretization allows to substantially reduce the numerical integration work by taking advantage of well-known analytical properties of the spherical harmonics. It also permits (like with the previous 2D Fourier version) an effective a priori selection method for the discretization parameter in each sub-region, and allows to estimate the directivity of the pressure field by means of a natural definition of rescaled amplitude portraits. The accuracy and performance of the proposed formulation are demonstrated on a set of numerical examples that include results on an actual case study from the automotive industry.

Head shape analysis of National Football League Players

2021 ◽  
pp. 175433712110206
Author(s):  
Gwansik Park ◽  
Lee F Gabler ◽  
Ann M Bailey ◽  
Nathan Z Dau ◽  
Chris Sherwood ◽  
...  
Keyword(s):  
Shape Analysis ◽  
National Football League ◽  
Sagittal Plane ◽  
Three Dimensional ◽  
Principal Component ◽  
Shape Variation ◽  
Head Shape ◽  
Two Factors ◽  
Football Helmets ◽  
Statistical Shape

Understanding the size and shape variations of the head is important to the design of football helmets used to mitigate the risk of head injury. Current guidelines for selecting helmets use only the circumference of the player’s head to determine an appropriate size that may not offer the best fit and protection for every player. The goal of this study was to quantify key measurements of head shape to sufficiently characterize variability among players in the National Football League (NFL), focusing on the shape variation of the cranial region. Statistical shape analysis was performed on three-dimensional head scans of 87 contemporary NFL players to identify key features of head shape variability among the players’ heads. The principal component analysis revealed two factors that explained 87% of the head shape variance: (1) height and length of the head in the sagittal plane and (2) prominent back of the head with an oval shape in the transverse plane versus prominent forehead with a round shape. Four head shape measurements (circumference, length, breadth, and height) were then defined and quantified to describe the first two principal components. This information can facilitate improvements in the design of football helmets.

scholarly journals Overhaul of Three-D Image Based on Metamorphosis and Fabric Growing of Two-D Images

2020 ◽  
Vol 9 (3) ◽  
pp. 3466-3471
Keyword(s):  
Shape Analysis ◽  
Medical Image ◽  
Three Dimensional ◽  
Medical Image Processing ◽  
Physical Property ◽  
Initial Step ◽  
Practical Result ◽  
Normal Image ◽  
Segmented Image ◽  
Three Dimensional Models

Shape is a critical physical property of normal and artificial three-D images that describes their outside appearances. Understanding differences among shapes and displaying the inconstancy inside and outside the shape classes are considered for shape analysis, and are the major issues in numerous applications, from normal image visualization to medical imaging. During diagnosis in medical image processing it is impossible to analyze the diseased areas some time from three-D images. So for the purpose of diagnosing the diseased areas of three-D image, medical experts need two-D images. This paper addresses the overhaul of three dimensional models from two-D images. In the initial step the image is segmented using level set method. Later segmented image is extracted and registered for overhaul of three dimensional images using metamorphosis and fabric growing methods. The practical result shows the implementation of the suggested method.

A framework for the automatic annotation of car aesthetics

2007 ◽  
Vol 21 (1) ◽  
pp. 73-90 ◽  
Author(s):  
CHIARA E. CATALANO ◽  
FRANCA GIANNINI ◽  
MARINA MONTI ◽  
GIULIANA UCELLI
Keyword(s):  
Computational Models ◽  
Three Dimensional ◽  
Multimedia Data ◽  
Computer Assisted ◽  
Target Market ◽  
Automatic Annotation ◽  
Digital Models ◽  
Semantic Data ◽  
Three Dimensional Models ◽  
Definition Of

The design of a new car is guided by a set of directives indicating the target market, specific engineering, and aesthetic constraints, which may also include the preservation of the company brand identity or the restyling of products already on the market. When creating a new product, designers usually evaluate other existing products to find sources of inspiration or to possibly reuse successful solutions. In the perspective of an optimized styling workflow, great benefit could be derived from the possibility of easily retrieving the related documentation and existing digital models both from internal and external repositories. In fact, the rapid growth of resources on the Web and the widespread adoption of computer-assisted design tools have made available huge amounts of data, the utilization of which could be improved by using more selective retrieval methods. In particular, the retrieval of aesthetic elements may help designers to create digital models conforming to specific styling properties more efficiently. The aim of our research is the definition of a framework that supports (semi)automatic extraction of semantic data from three-dimensional models and other multimedia data to allow car designers to reuse knowledge and design solutions within the styling department. The first objective is then to capture and structure the explicit and implicit elements contributing to the definition of car aesthetics, which can be realistically tackled through computational models and methods. The second step is the definition of a system architecture that is able to transfer such semantic evaluation through the automatic annotation of car models.

scholarly journals AlphaFold-Predicted Structures of KCTD Proteins Unravel Previously Undetected Relationships among the Members of the Family

Biomolecules ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1862
Author(s):  
Luciana Esposito ◽  
Nicole Balasco ◽  
Giovanni Smaldone ◽  
Rita Berisio ◽  
Alessia Ruggiero ◽  
...  
Keyword(s):  
Structural Information ◽  
Three Dimensional ◽  
Structural Data ◽  
Protein Family ◽  
General Sequence ◽  
Btb Domain ◽  
The Family ◽  
Three Dimensional Models ◽  
Definition Of ◽  
Sequence Similarities

One of the most striking features of KCTD proteins is their involvement in apparently unrelated yet fundamental physio-pathological processes. Unfortunately, comprehensive structure–function relationships for this protein family have been hampered by the scarcity of the structural data available. This scenario is rapidly changing due to the release of the protein three-dimensional models predicted by AlphaFold (AF). Here, we exploited the structural information contained in the AF database to gain insights into the relationships among the members of the KCTD family with the aim of facilitating the definition of the structural and molecular basis of key roles that these proteins play in many biological processes. The most important finding that emerged from this investigation is the discovery that, in addition to the BTB domain, the vast majority of these proteins also share a structurally similar domain in the C-terminal region despite the absence of general sequence similarities detectable in this region. Using this domain as reference, we generated a novel and comprehensive structure-based pseudo-phylogenetic tree that unraveled previously undetected similarities among the protein family. In particular, we generated a new clustering of the KCTD proteins that will represent a solid ground for interpreting their many functions.

scholarly journals Implementing the Automatic Generation of 3D Statistical Shape Models with ITK

2006 ◽  
Author(s):  
Tobias Heimann ◽  
Ipek Oguz ◽  
Ivo Wolf ◽  
Martin Styner ◽  
Hans-Peter Meinzer
Keyword(s):  
Cost Function ◽  
Model Building ◽  
Three Dimensional ◽  
Automatic Generation ◽  
Statistical Shape Models ◽  
Shape Models ◽  
Statistical Shape ◽  
Real World Datasets ◽  
Value Decomposition ◽  
Spatial Locations

Statistical Shape Models are a popular method for segmenting three-dimensional medical images. To obtain the required landmark correspondences, various automatic approaches have been proposed. In this work, we present an improved version of minimizing the description length (MDL) of the model. To initialize the algorithm, we describe a method to distribute landmarks on the training shapes using a conformal parameterization function. Then, we introduce a novel procedure to modify landmark positions locally without disturbing established correspondences. We employ a gradient descent optimization to minimize the MDL cost function, speeding up automatic model building by several orders of magnitude when compared to the original MDL approach. The necessary gradient information is estimated from a singular value decomposition, a more accurate technique to calculate the PCA than the commonly used eigendecomposition of the covariance matrix. In this work, we first present a basic version where spatial locations are used in the MDL cost function; next, we introduce an extended version where any combination of features can be used as a metric. As an example application, we present results based on local curvature measurements. Finally, we present results for synthetic and real-world datasets demonstrating the efficiency of our procedures and give details about the implementation using the Insight Toolkit (ITK).

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