Shape from Profiles

2005 ◽  
Author(s):  
Roberto Cipolla ◽  
Kwan-Yee K. Wong
Keyword(s):  
Motion Estimation ◽  
State Of The Art ◽  
3D Models ◽  
Model Estimation ◽  
Model Reconstruction ◽  
The Creation ◽  
The Way

This chapter discusses profiles or outlines which are dominant features of images. Profiles can be extracted easily and reliably from the images and can provide information on the shape and motion of an object. Classical techniques for motion estimation and model reconstruction are highly dependent on point and line correspondences, hence they cannot be applied directly to profiles which are viewpoint dependent. The limitations of classical techniques paved the way for the creation of different sets of algorithms specific to profiles. In this chapter, the focus is on state-of-the-art algorithms for model reconstruction and model estimation from profiles. These new sets of algorithms are capable of reconstructing any kind of objects including smooth and textureless surfaces. They also render convincing 3D models, reinforcing the practicality of the algorithm.

scholarly journals Shedding light on pre-Columbian crania collections through state-of-the-art 3D scanning techniques

2021 ◽  
Vol 12 (24) ◽  
pp. 1
Author(s):  
Gizéh Rangel-de Lázaro ◽  
Adrián Martínez-Fernández ◽  
Armando Rangel-Rivero ◽  
Alfonso Benito-Calvo
Keyword(s):  
3D Printing ◽  
State Of The Art ◽  
Structured Light ◽  
3D Models ◽  
3D Reconstructions ◽  
Structured Light Scanner ◽  
New Knowledge ◽  
Caribbean Area ◽  
The Caribbean ◽  
The Creation

<p class="VARAbstract">During the 19<sup>th</sup> and 20<sup>th</sup> centuries, numerous museums, scientific societies, and royal academies were founded in Europe and America. In this scenario, the Anthropological Museum Montané was founded in Havana, Cuba. Its collection has grown over the years, thanks to researchers, antiquarians, and amateurs. Since its foundation, the Museum Montané has become an essential institution for anthropological and archaeological research in the region. Nowadays, the Museum Montané, like other museums in developing countries, faces a challenge in the introduction of state-of-the-art technologies to digitizing exhibits and the creation of innovative projects to attract visitors. The current possibilities of virtualization of cultural heritage using digital technologies have a favorable impact on the preservation, access, and management of museum collections. The use of three-dimensional (3D) models fosters engagement with visitors, stimulates new forms of learning, and revalorizes the exhibits. In the current study, we use a hand-held structured light scanner to create 3D reality-based models of pre-Columbian crania from the Caribbean and South American collection of the Anthropological Museum Montané. The resulting 3D models were used for producing 3D printing replicas and animated videos. The 3D resources derived will encourage new knowledge through research, and provide broader access to these pre-Columbian crania collection through learning and outreach activities. The significance of digitizing these specimens goes beyond the creation of 3D models. It means protecting these fragile and valuable collections for future generations. The methodology and results reported here can be used in other museums with similar collections to digitally document, study, protect, and disseminate the archaeological heritage. Going forward, we seek to continue exploring the application of novel methods and digital techniques to the study of the pre-Columbian crania collections in Latin American and the Caribbean area.</p><p class="VARAbstractHeader">Highlights:</p><ul><li><p>A hand-held structured light scanner was used to acquire 3D reality-based models of pre-Columbian crania. The 3D models resulting were used for 3D printing replicas and 3D animations.</p></li><li><p>This study provides unprecedented 3D reconstructions of pre-Columbian crania in the Caribbean area, and new 3D reconstructions of artificially deformed crania from South America.</p></li><li><p>The 3D resources created will encourage new knowledge through research, and provide broader access to these pre-Columbian crania collection through learning and outreach activities.</p></li></ul>

Attention Sustainability Impact on Social Status in the Class

2020 ◽  
Vol 8 (1) ◽  
pp. 37-46
Author(s):  
Stanislava Varadinova
Keyword(s):  
Social Status ◽  
Communication Skills ◽  
School Dropout ◽  
Learning Material ◽  
Early School ◽  
The Social ◽  
The Creation ◽  
The Individual ◽  
The Way ◽  
Positive Environment

The attention sustainability and its impact of social status in the class are current issues concerning the field of education are the reasons for delay in assimilating the learning material and early school dropout. Behind both of those problems stand psychological causes such as low attention sustainability, poor communication skills and lack of positive environment. The presented article aims to prove that sustainability of attention directly influences the social status of students in the class, and hence their overall development and the way they feel in the group. Making efforts to increase students’ attention sustainability could lead to an increase in the social status of the student and hence the creation of a favorable and positive environment for the overall development of the individual.

Systematicity and Normative Justification

2017 ◽  
Author(s):  
Kevin Thompson
Keyword(s):  
Political Philosophy ◽  
Unique Form ◽  
The Core ◽  
The Creation ◽  
Normative Justification ◽  
The Way

This chapter examines systematicity as a form of normative justification. Thompson’s contention is that the Hegelian commitment to fundamental presuppositionlessness and hence to methodological immanence, from which his distinctive conception of systematicity flows, is at the core of the unique form of normative justification that he employs in his political philosophy and that this is the only form of such justification that can successfully meet the skeptic’s challenge. Central to Thompson’s account is the distinction between systematicity and representation and the way in which this frames Hegel’s relationship to the traditional forms of justification and the creation of his own distinctive kind of normative argumentation.

scholarly journals Dense cellular segmentation for EM using 2D–3D neural network ensembles

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Matthew D. Guay ◽  
Zeyad A. S. Emam ◽  
Adam B. Anderson ◽  
Maria A. Aronova ◽  
Irina D. Pokrovskaya ◽  
...  
Keyword(s):  
Blood Platelets ◽  
Semantic Segmentation ◽  
3D Models ◽  
Image Features ◽  
Cell Models ◽  
Whole Cells ◽  
Large Numbers ◽  
The Creation ◽  
Segmentation Task ◽  
Neural Network Ensembles

AbstractBiologists who use electron microscopy (EM) images to build nanoscale 3D models of whole cells and their organelles have historically been limited to small numbers of cells and cellular features due to constraints in imaging and analysis. This has been a major factor limiting insight into the complex variability of cellular environments. Modern EM can produce gigavoxel image volumes containing large numbers of cells, but accurate manual segmentation of image features is slow and limits the creation of cell models. Segmentation algorithms based on convolutional neural networks can process large volumes quickly, but achieving EM task accuracy goals often challenges current techniques. Here, we define dense cellular segmentation as a multiclass semantic segmentation task for modeling cells and large numbers of their organelles, and give an example in human blood platelets. We present an algorithm using novel hybrid 2D–3D segmentation networks to produce dense cellular segmentations with accuracy levels that outperform baseline methods and approach those of human annotators. To our knowledge, this work represents the first published approach to automating the creation of cell models with this level of structural detail.

scholarly journals Robust Visibility Surface Determination in Object Space via Plücker Coordinates

2021 ◽  
Vol 7 (6) ◽  
pp. 96
Author(s):  
Alessandro Rossi ◽  
Marco Barbiero ◽  
Paolo Scremin ◽  
Ruggero Carli
Keyword(s):  
Finite Number ◽  
State Of The Art ◽  
Lossless Compression ◽  
3D Models ◽  
Optimal Result ◽  
Object Space ◽  
Plücker Coordinates ◽  
Determination Methods

Industrial 3D models are usually characterized by a large number of hidden faces and it is very important to simplify them. Visible-surface determination methods provide one of the most common solutions to the visibility problem. This study presents a robust technique to address the global visibility problem in object space that guarantees theoretical convergence to the optimal result. More specifically, we propose a strategy that, in a finite number of steps, determines if each face of the mesh is globally visible or not. The proposed method is based on the use of Plücker coordinates that allows it to provide an efficient way to determine the intersection between a ray and a triangle. This algorithm does not require pre-calculations such as estimating the normal at each face: this implies the resilience to normals orientation. We compared the performance of the proposed algorithm against a state-of-the-art technique. Results showed that our approach is more robust in terms of convergence to the maximum lossless compression.

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